COO-2990-6 Distribution Category UC-94a

INVESTIGATION OF METAL FLUORIDE THERMAL

ENERGY STORAGE MATERIALS

AVAILABILITY, COST AND CHEMISTRY

FINAL REPORT

J. L. EICHELBERGER

- NOTICE- This report was prepared as an account of work sponsored by the United States Government. Neither the United States nor the United States Energy Research and Development Administration, nor any of their employees, nor any of their contractors, subcontractor*, or their employees, makes any DECEMBER, 1976 warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any information, apparatus, product or process disclosed, or represents that its use would not infringe privately owned rights.

CONTRACT NO. EY-76-C-02-2990*000

PREPARED FOR

ENERGY RESEARCH AND DEVELOPMENT

ADMINISTRATION OFFICE OF CONSERVATION DIVISION OF ENERGY STORAGE SYSTEMS

PENNWALT CORPORATION TECHNOLOGICAL CENTER KING OF PRUSSIA, PENNSYLVANIA 19406

rSSTRIBOTION QF THIS DOCUMENT IS UNLIMITED DISCLAIMER

This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency Thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. DISCLAIMER

Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. FOREWORD This report was prepared by Pennwalt Corporation, King Of Prussia, Pennsylvania, under U.S. Energy Research and ^Development Administration Contract EY-76-C-02-2990*000, formerly E(ll-l)-2990. The contract was issued by Harold N. Miller, Director, Chicago Contracts Management Office. Technical monitoring was begun by C. J. Swet, Thermal Energy Storage Program Manager of the Division of Conservation Research and Develop• ment, and was completed by William Masica and Joseph Joyce of the NASA-Lewis Research Center. This report covers the work carried out during the period July 15, 1976 - December 15, 1976 and was submitted by the author in December, 1976.

li ACKNOWLEDGEMENTS In addition to the King of Prussia Technological Center of Pennwalt Corporation, the Ozark-Mahoning Division of Penn• walt, Tulsa, Oklahoma, made significant contributions to the performance of this contract. The most active participants assisting the principal investigator were Dr. Hyman Gillman and Mr. Fred Loomis of the Technological Center, and Dr. Charles Lindah.l, Dr. Dayal Meshri, and Mr. Charles Ramming of Ozark-Mahoning.

111 ABSTRACT

Storage of thermal energy in the 400-1000°C range is attracting increasing consideration for use in solar power, central power, vehicular, and commercial process systems. This study investigates the practicality of using metal fluorides as the heat storage medium. The projected avail• ability of metal fluorides has been studied and is shown to be adequate for widespread thermal storage use. Costs are projected and discussed in relation to thermal energy storage applications. Phase diagrams, heats of fusion, heat capacities, vapor pressures, toxicity, stability, volume changes, thermal conductivities, fusion kinetics, corrosion, and container materials of construction for a wide range of fluorides have been examined. Analyses of these data in consideration of thermal energy storage requirements have resulted in selection of the most cost- effective fluoride or fluoride mixture for each of 23 temperature increments between 400 and 1000°C. Thermo- physical properties of these 23 materials are presented.

Comparison of fluoride with non-fluoride materials shows that the fluorides are suitable candidates for high temperature applications on the bases of cost, heat capacity/unit volume, heat capacity/unit weight, corrosive properties, and availability.

iv TABLE OF CONTENTS

Page I. EXECUTIVE SUMMARY 1 Foreword 1 Metal Fluoride Availability 2 Metal Fluoride Costs 6 Metal Fluoride Chemistry 8 Major Study Conclusions 13 Recommendations 13 II. INTRODUCTION 14 III. APPLICATIONS 17 IV. AVAILABILITY 21 A. Fluorine Supply and Demand 22 B. Fluorine Occurrence and Geology 24 C. Calcium Fluoride Supply 27 1. World Reserves and Resources 27 2. U.S. Reserves and Resources 35 D. Fluosilicic Acid Supply 51 E. Other Fluorine Sources 69 F. Fluorine Demand 71 1. Fluorine Demand - Steel Production 75 2. Fluorine Demand - Aluminum Production 77 3. Fluorine Demand - Fluorocarbon Production 80 4. Fluorine Demand - Other Applications 83 G. Future Trends of Fluorine Supply and Demand 86 1. Demand 86 2. Supply 86 H. Supply - Demand of Metals 93 I. Supply - Demand of Metal Fluorides 105 J. Supply - Requirements of Metal Fluorides for 106 Heat Storage

v TABLE OF CONTENTS (Continued)

Page V. METAL FLUORIDE COSTS 108 A. Current Costs 108 B. Future Costs .115 C. Non-Accountable Costs 126 VI. CHEMISTRY EVALUATION 128 A. Classification and Data Quality 128 B. Metal Fluoride Synthesis 130 C. Purification 143 D. Vapor Pressure and Thermal Stability 146 E. Hydrolytic Stability 153 F. Corrosion 154 G. Melting Points and Phase Diagrams 163 H. Heat Contents 166 1. Heat of Fusion 167 2. Heat of Transition 175 3. Heat Capacity and Sensible Heat 175 I. Volume Changes and Density 186 J. Viscosity 190 K. Thermal Conductivity 193 L. Supercooling 199 M. Selected Fluoride Compositions 200 VII. EXPERIMENTAL 213 VIII. SAFETY 214 IX. RECOMMENDATIONS 216 X. REFERENCES 218 XI. APPENDIX

VI TABLE OF TABLES

Page I. Applications for Heat Storage 18 II. Fluorine Minerals 25 III. World Production and Reserves of Calcium Fluoride 28 IV. States of Mexico in Which Major Fluorspar Deposits Occur 32 V. Mexican Producers of Fluorspar 36 VI. Fluorspar reserves and resources in the U.S. by States 1974 37 VII. Domestic Fluorspar Producers by State 41 VIII. Some Companies Involved in Phosphate Production 53 IX. Some of the Companies Involved in Fluosilicic Acid Recovery and Conversion 66 X. Partial List of Inorganic Chemicals Containing Fluorine 85 XI. United States Projections and Forecasts for Fluorine by End Use, 1973 and 2000 87 XII. Summary of Forecasts of U.S. and Rest of World fluorine Demand, 1974-2000 88 XIII. Fluorine Supply Potential From The Phosphate Industry 91 XIV. Abundance, Mass, Reserves, and Resources of Some Metals in the Earth's Crust and in the United States Crust 95 XV. Abundance of Some Elements in the Earth's Crust 96 XVI. Production of Minerals (Metal Content) in 1974 99 XVII. Potential U.S. Resources of Some Important Mineral Commodities, in Relation to Minimum Anticipated Cumulative Demand to Year 2000 A.D. .100 XVIII. Supply Forecasts for Selected Minerals Based on Proven World Reserves 102 XIX. Prices and Estimated Production Costs of Fluoride Compound s 109 XX. Prices of Starting Materials for Metal Fluorides 111 XXI. Estimated Current Prices of Metal Fluoride Compounds 112 XXIa. Estimated Future Production Costs and Prices of Metal Fluorides 116 XXII. Vapor Pressure of Fluoride Salts 147 XXIII. Melting Points of Some Aluminum Fluoride Compositions 151 vn TABLE OF TABLES (Continued)

Page XXIV. Gibbs Free Energies of Selected Fluorides 155 XXV. Fluoride-Metal Corrosion Experiments , 160 XXVI. Heats of Fusion of Fluoride Salts 168 XXVII. Heats of Fusion of Alkali and Alkaline Earth Fluorides 173 XXVIII. Heats of Transition of Fluoride Salts 177 XXIX. Thermodynamic Equations For Sodium Fluoride 178 XXX. Specific Heat and Heat Content Functions of Selected Metal Fluorides 180 XXXI. Heat Contents of Selected Metal Fluorides 182 XXXII. Densities and Volume Changes of Fluoride Salts 187 XXXIII. Viscosity of Fluoride Salts 191 XXXIV. Thermal Conductivity of Fluoride Salts 194 XXXV. Melting Points of Selected Metal Fluoride Salts 202 XXXVI. Selected Metal Fluoride Salts 207

viii TABLE OF FIGURES Page I. Metal Fluoride Selection Criteria 16 II. Relationships Among Sources of Supply and Demand for Fluorine - 23

III. CaF2 World Production 29 IV. CaF_ Known World Reserve 30 V. Mexico Fluorspar Production 33 VI. Canada Fluorspar Production 34 VII. Fluorspar in Canada, 1972 38

VIII. CaF2 Known U.S. Reserves 40 IX. CaF- U.S. Production Finished (All Grades) 44 X. U.S. Stocks : Mine 46

XI. CaF2 (97%) U.S. Stockpile 47 XII. U.S. Imports 48 XIII. U.S. Imports by Country of Origin 49

XIV. U.S. Fluorspar Equivalent From H2SiF6 64 XV. U.S. Fluorspar Consumption (All Grades) 73 XVI. U.S. Fluorspar Consumption and Imports 74 XVII. Historical Demand and Trend Projections of Fluorine Used in Steel Production 76 XVIII. Fluorine Values in the Aluminum Industry 79 XIX. Projections of Fluorine Use in the Aluminum Industry 81 XX. Historical Demand and Trend Predictions of Fluorine Used in Chemical Production 82 XXI. Historical Trend Projection of Fluorine Use in the Ceramic Industry 84 XXII. Fluorine Demand Projection 89 XXIIa. Change in World Proved Reserves 1950-70 103 XXIII. 1975 Imports Percentage of Minerals and Metals U.S. Consumption 104 XXIV. Time-Price Relationship for Fluorine 119 XXV. The Enthalpy and Enthalpy of Fusion of LiAlF , Na,AlF and K A1F fi° 176 j 6c 02. 6C XXVI. Heat Contents Above 298.16°K 183

ix TABLE OF FIGURES (Cont'd) Page

XXVII. Enthalpy Curve, H° - H° _ _5 in kcal/mole for

NaMgF3 * 184

XXVTII. Enthalpy Curve, Hi, - H° Q 15, in kcal/mole, for

(0.782NaF + 0.21MgF2) 184

XXIX. Enthalpy Increments H - H2gQ ., _ and Enthalpy of Fusion of the Eutectic Mixture 21.8 mole % Na-AlFg + 78.2 mole % at 1162°K 185 XXX. Lithium Fluoride Thermal Conductivity Variation with Temperature 197 XXXI. Effect of Impurities on the Thermal Conductivity Of FLINAK (11.5NaF/42KF/46.5LiF) 198 XXXII. Metal Fluoride Selection Process 201 I. EXECUTIVE SUMMARY Foreword Storage of thermal energy is recognized to offer a means of achieving improved efficiencies in energy production and use. The potential applications range from small scale heat storage,' such as for artificial heart pumps, to large scale storage, such as for central power plant load leveling, with each application having its own set of requirements. Although high energy density, low cost, high thermal conductivity, low volatility, and low toxicity are commonly desired characteristics, their relative importance varies from application to application. The relation• ships among energy storage capacity, volume, and cost are particularly sensitive to specific application requirements: the higher the energy density/unit volume, the less volume will be required and smaller equipment will be needed.

At the time this study began in July, 1976, some conceptual engineering design work had been done, some experimental devices had been tested, and a variety of heat storage materials were under investigation. However, optimum choices of heat storage media for various temperature ranges had not been made and knowledge was just beginning to be assembled concerning trade• offs among cost factors, material properties, and equipment design.

One result of early studies was the recognition that metal fluorides possess many of the qualities required for storage of energy. In addition to latent heats on a volume basis that surpass those of any other potentially practical material, the metal fluorides were said to have high thermal conductivities, good stabilities, low vapor pressures, and no supercooling. It has also been shown that addition of a small quantity of getter material to fluoride eutectics inhibits corrosion of stainless steel. Because the metal fluorides appear to be attractive candi• dates, several engineering studies have selected them for further investigation and development. In general, however, it was still necessary to determine the future availability of

-1- metal fluorides if large, new markets were found for them, as well as the potential costs of metal fluorides if they were manufactured on a large scale. In addition, a compilation of the thermophysical data available for these materials was needed. This study, consequently, was undertaken to fill these needs and to assemble the available knowledge about metal fluorides that would be useful in the material selection process. As part of this effort, we have endeavored to select the most cost- effective metal fluorides for each of a number of different temperature ranges. The report is divided into three main sections, treating availability, cost, and chemistry as separately as possible. The study approach is given in Figure 1 and materials selection criteria are given in Figure 2. Extensive details are presented in the Appendix concerning metal fluoride sources, supply- demand relationships of metals, and phase diagrams of metal fluorides. Metal Fluoride Availability The availability of metal fluorides for heat storage appli• cations is dependent on the reserves and resources of fluorine and the metals selected. Also of fundamental importance are the supply-demand relationships of fluorine, the metals, and the metal fluorides. The primary source of fluorine is and will remain the min• eral fluorspar, CaF_. The North American continent holds 26% of the world's known high quality deposits of fluorspar, prin• cipally found in northern Mexico, the mountain states, and a region of southern Illinois and western Kentucky. The particular richness of Mexican deposits and the Mexican labor structure permit that country currently to control the world fluorspar market. Production is well below capacity and can be increased at least 10% on demand. According to the Bureau of Mines, world fluorspar reserves (proven deposits of fluorspar that can be extracted profitably with existing technology and economic conditions) are sufficient to satisfy world needs for the next 20 years. -2 FIGURE 1. METAL FLUORIDE SELECTION CRITERIA

Best Cost/Effective Fluoride Materials I Best-Technology Best-Cost Effective Materials Materials I I _r 1 X 1 Technical Technical Demand/Supply Quantity & Cost Requirements Data Base Relationships Requirements T I I 1 Thermophysical Chemical Financial Availability I Data Base Evaluation Data Base Data Base

Data Selection & Alternate Opportunities Quantity Accumulation Current Costs Information

Corrosion Experimental Future Costs Source Data Information Reactions Processing Costs Stabilities Transportation Costs Figure 2. Metal Fluoride Selection Process

Metal Prices -> Reject Most Costly

Toxicity Reject Most Toxic

Stability Reject Those Which Decompose

JL Reject Those With High VolatilitifyV L Vapor Pressure

Heat of Fusion Reject Those With LowAHf ±L Availability Reject Rare Materials ■>

Reject Inappropriate Phase Diagrams Melting Materials

Corrosivity Reject Those With High Corrosion Rates

Thermal Conductivity ^ Reject Poor Conductors

1L Reject Low Specific Specific Heat Heat Material

_i Reject Materials With Volume Change High % Change ±. Specific Application Reject Those With Requirements Non-Applicable Parameters JL MF Price Reject High Cost Materials ■>

^ SELECTED MATERIAIAL |

-4- A significant secondary source of fluorine is fluosilicic acid, H2SiF6, obtained as a by-product of the phosphate industry. Phosphate rock contains about 3.5% fluorine by weight, or about 2.3 billion tons of fluorine based on currently commercial world phosphate deposits. During processing, much of this fluorine is volatilized as silicon fluoride, creating air contamination. Only a small portion of this fluorine is recovered at present because of lack of a suitable market. The rest is a pollutant. For a large demand of metal fluorides, 226,000 tons/year of fluorine could be available from this source under current economic and technical conditions. This figure is expected to grow to 726,000 tons/year by 2000. From all sources 294,000 tons/year of fluorine, or greater than 590,000 tons/year of metal fluorides could be provided now without competition with existing markets for fluorine.

These other markets consist largely of the steel, aluminum, and chlorofluorocarbon compound industries. There is potential for significantly lower amounts of fluorine to be used in these industries that might create an oversupply and price-competition situation. Data for world production, U. S. supply, and U. S. con• sumption according to major uses and other supply/demand relation• ships were analyzed for the following elements: Al, Sb, Ba, Be, B, Cd, Cr, Co, Cu, Fe, Pb, Ca, Li, Mg, Mn, Mo, Ni, K, P, mixed rare earths, Na, Si, S, Sn, Ti, W, V, Zn, and Zr. ~Of all the elements, Si, Al, Fe, Ca, Na, K, Mg, Ti, Mn, and Sr are the most abundant and are therefore the best candidate metals, on the basis of availability for combination with fluorine for heat storage materials. Calculations show that 590,000 tons of metal fluoride salts would be required for 50 thermal energy storage systems of 500 mw capacity. This is approximately the amount of material that we predict can be available annually under current technology and market conditions without competition for resources from other applications. Similar calculations show that 5 million

_5_ residential storage units each containing 88 kg of fluoride salts, could be manufactured each year. Metal Fluoride Costs The current prices and estimated production costs of selected fluorine compounds are presented in Table 1. Current prices, with the few exceptions of those for HF, CaF2, H SiFg,

A1F_, and Na_AlFfi, are based on low production volumes. The production cost estimates are based on state-of-the-art chemical reactions and production volumes of 91,000 metric tons/year. The estimates were made six times to show the effects of various fluorine sources on metal fluoride costs and to show future trends. In one instance, hydrofluoric acid, obtained at market price, was chosen as the fluorine source. In another case, the cost of hydrofluoric acid was lowered to reflect the ability of a hydrofluoric acid producer to undercut the market price if he were to manufacture the metal fluoride himself. In the third case, fluosilicic acid, obtained at market price, was chosen as the fluorine source. In the fourth, fifth, and sixth cases, the cost of the fluosilicic acid was assumed to be negligible, reflecting its cost to a fertilizer manufacturer, who, for lack of market, must usually pay to dispose of this pollutant. Note that the estimated production costs are signif• icantly lower than current market prices, indicating economies of scale. In all cases, fluosilicic acid appears to be the reagent of choice on a cost basis. On the other hand, hydro• fluoric acid has been more widely employed because of avail• ability and reactivity. As a result, the procedures using hydrofluoric acid are more highly developed.

The least expensive metal fluoride compounds are those con• taining Ca, Na, Mg, Al, Si, Ba, K, and Sr. These compounds and most of their mixtures have melting points above 450°C. If fluoride materials are desired that have lower melting points, then mixtures that contain the expensive compounds, LiF, SnF2, and ZrFA are required.

6- Table 1. Current Prices and Estimated Production Costs of Selected Metal Fluorides

Estimated Production Costs ($/kg) Current Based on Metal Selling Based on HF Based on HF H2SiF6 Based on H2SiFg Free Fluoride Price @ 9lCAg @ 62£Ag @ 36<=Ag 1976 1985 2000

NaF 0.74 0.58 0.44 0.33 0.11 0.18 KF 1.46 0.73 0.64 0.58 0.42 0.49 0.76

MgF2 0.87-1.71 0.76 0.58 0.47 0.18 0.18 0.18

CaF2 0.12 0.13* 0.16*

BaF2 1.29 0.56 0.49 0.44 0.33 0.36 0.36

TiF 77.78 1.04 , 4 1.27 0.93 0.67 0.69 0.78 "J1 A1F- 0.39 0.84 0.62 0.49 0.18 0.18 0.18

SrF2 50.44 0.84 0.73 0.69 0.53 0.60 0.78

PbF2 30.27 1.00 0.96 0.93* 0.93* LiF 5.38 3.27 3.04 2.93 2.58 2.78 2.78

CUF2 121.11 2.91 2.80 2.31 2.13 2.78 3.13

NiF2 202.22 3.96 3.82 3.73 3.56 3.71 4.00

CrF3 1.80 5.91 5.58 5.16 4.91 5.13 6.44

SnF0 12.44 16.89* 25.16*

*Based on HF @ 62$Ag ^Mined; selling price The influence of degree of purity on selling price is of special concern because the required level of purification for heat storage purposes is not now known. The purification steps included in the program that gave the production costs in Table 1 are considered sufficient to give 99% pure compounds. The expected increase in production costs for an inexpensive metal fluoride can be as much as 13% if extensive additional purification procedures are required. Metal Fluoride Chemistry Investigations of melting poinds and phase diagrams" of metal fluorides and their mixtures have shown the existence of a variety of suitable candidates for at least every 50°C tempera• ture interval between 450 and 1000°C. Other candidates above 1000°C were found, and higher cost candidates were even found for the 200-450°C range. It was found, however, that many of the fluoride salt property data presented without qualification in secondary sources really was calculated and not experimental. The data consequently can only be considered to be order-of-magnitude indications of actual properties. Of paramount importance in selecting the most suitable candidates in each temperature range is stability to end use conditions and corrosive effects on the container. All of the metal fluorides interact with water at high temperatures to give volatile products. Therefore, use of metal fluorides for thermal storage is practical only in closed containers. Any appreciable vapor pressure would either buckle and rupture the container or would require reinforced (and therefore expensive) container construction. Because of vapor pressure considerations, the ammonium fluoride salts, the tetrafluoroborates, the fluorosilicates, some aluminum com• pounds, the fluoroferrates, and the fluorotitanates are less likely candidates. Fortunately, many metal fluorides have very low vapor pressures, even at temperatures of 100°C above their melting points. Lithium fluoride is perhaps the most

-8- stable in this respect. Some fluorides are hygroscopic, as exemplified by KF, whereas others, such as NaF, are not. Many

metal fluorides will form hydrates, such as KF«4H20, KF«2H20, and A1F_.H_0. The water of hydration can be removed from many of these fluorides simply by heat and vacuum; however, other hydrates are difficult to dry without forming metal oxide and hydrofluoric acid. In regards to oxidative stability, most of the fluorides discussed in this report are stable in dry air, even at high temperatures. Among the exceptions, the most notable is FeF_. For any heat storage medium, the choice of material of construction for the container is of critical significance in terms of system cost, lifetime, and performance. A high degree of corrosion resistance is required for long service life, but in general, the more corrosion resistant a material is, the higher is its cost. On these bases, primary consideration should be given to the alkali, alkaline earth, and silicon fluorides because they appear to be the most stable. Titanium fluorides and non-

transition metal fluorides such as ZnF_, A1F , SnF3, SnF2, and PbF_ may be useful for heat storage on the basis of corrosive stability; however, more extensive corrosion cycling data must be gathered for these materials before a decision regarding their usefulness can be made. In general, the rate of corrosion is very dependent on the type of container material as well as the particular fluoride salt being studied. The data suggest that a number of materials look promising for the containment of fluoride salts. Those that partially consist of molybdenum or columbium have the best corrosion resistance, but these more exotic metals may be too expensive for many high temperature heat storage applications. At wall surface temperatures of 600 to 650°C, the corrosion experienced by 321 stainless steel is only. 0.8 to 1.0 mm/year. However, other research has been done to decrease the corrosion of the less expensive alloys by either purification of the

9- fluoride salts or by addition of a getter such as aluminum to the fused salt. The latter approach is reported to be quite promising. After long term treatment at 850°C (more than 10,000 cycles), aluminum treated mixtures caused no corrosion to 316-type stainless steel. Studies of this type are con• tinuing and offer the possibility that inexpensive fluoride containing heat storage systems may be developed. 3 Heats of fusion of greater than 1673 MJ/m (based on ambient densities) were found for 24 fluoride materials. Determination of the heats of fusion of mixtures contain•

ing NaF and increasing amounts of Si02 indicates that small amounts (< 1%) of impurities will have little effect on this property, but that large amounts (2-5%) will have a signifi• cant effect. On a volume basis, magnesium fluoride is the most inter- 3 esting, having a AHm of 2920 MJ/m . Solid-solid transformations generally do not occur in' fluoride salts, but when they do, heats of fusion are lower. If the maximum AH is desired at the fusion point, solid-solid transitions are probably not useful. However, if heat storage is desired over a range of temperature, then those mixtures with substantial heats of transition may be particularly applicable. One such candidate is Na^AlF-, whose total of AH and AHm is 1841 MJ/m3. Sensible heat contents were calculated for a variety of fluoride materials between ambient temperature and the melting points. They vary between 1310 MJ/m3 for LiF/LiOF and 5561 3 MJ/m for CaF2. Sensible heat content for a variety of fluoride materials for the 100°C temperature intervals above their melting 3 points fall in the 238-812 MJ/m range.

Thermal conductivities range from 0.84-4.18 J/m»sec.°C. Volume changes vary between 7% to 49% from ambient to greater than the melting point temperatures. Viscosities are on the order of 1.7-15 centipoise at the melting point.

-10- in general, metal fluoride salts do not supercool.

Based on these properties and the selection criteria shown in Figure 2, a fluoride composition was picked for each tempera• ture range (See Table 2). Other fluorides may be more suitable depending on specific system trade-off studies. However, these selections give a good picture of what is available in each temperature range at what price, etc.

A number of the compositions listed in Table 2, especially in the intermediate temperature ranges, contain potassium fluoride, a compound that is difficult to keep dry. However, KF should not be eliminated because of this property. All of the fluoride salts must be well dried before sealing in their containers and careful handling procedures must be used in order to ensure the purity of the materials. After manufacture, KF and the other metal fluorides should be kept and transferred under dry conditions. In addition, much of operational success depends on the elimination of corrosion, and the most promising method of this is the use of an aluminum or other getter mate• rial. This getter would be expected to remove last traces of moisture. Other components listed in Table 2 contain the chloride ion. Although the corrosion caused by chlorides is recognized to be greater than that caused by fluorides, there are indica• tions that proper drying and use of getter techniques may substantially alleviate this potential problem.

Although many A1F3 containing mixtures appear to be prom• ising in a variety of temperature ranges, systematic examination for vapor pressure build-up will be a precautionary requirement. Five of the mixtures in Table 2 contain lithium, an element generally assumed to have potential availability problems. Calculations show that the amount of lithium contained in these mixtures ranges from 0.5 to 9.4% by weight.

-11- Table 2. Selected Metal Fluoride Salts

Temperature Melting Range Composition Point Estimated Selling Price Ijta ^C 3 kg/mole XJAq MJ/fa3*

200-250 75.5NaF/24.5SnP2 240 S.29

250-300 70Na3AlP6/30AlCl3 300 0.66 300-350 85.3KF/14.7SnP, 320 3.62

350-400 31.0KF/4.1AlF3/64.9Zr?4 400 3.64

401-450 27.1LiP/ll.9NaF/55.1KF/5.9MgF2 449 1.33 3.424 7.0 699 1807 451-475 29.2L1F/11.7HaP/59.1KF 454 1.42 3.567 4.09 414 1046

476-500 1.9LiF/42.6KF/55.5AlF3 490 0.47

501-525 20.1HaF/79.9ZrF4 510 4.27 16.322 6.4 25S 983

526-550 5.8HaF/28.9KC1/65.3Na2C03 538 0.07

551-575 25.9Na2C03/38.8NaCl/35.3NaP 57S 0.09 0.16 576-600 11.5MgF2/88.5MgCl2 596 1.36 •601-625 35.2LiF/38.3NaP/26.5CaF2 615 3.790 5.83 636 1795 635 0.64 626-650 45.2NaF/54.8ZnP2 675 0.53 651-675 56Na3AlF6/6.2AlF3/37.8CaPj 676-700 27.9NaF/72.1NaCl 660 0.07 701-725 32.5NaF/67.5KF 721 0.47 1.157 7.22 585 1469 745 0.16 726-750 51.7NaF/34.1CaP2/14.2MgF2 .457 6.7 565 1678 750 0.84 751-775 24.5Ma3AlFg/62.1KF/8.9LiF/4.5Al20j 0.27 776-800 53.6NaF/17.8KF/28.6MgPj 798 .752 810,818 0.13 801-825 51.8NaF/48.2CaF2 .378 7.65 590 1686 830 0.18 826-850 66.9NaF/33.1MgP2 .517 9.27 649 1920 855 0.60 851-875 25.1»aF/74.9SrP2 882 0.18 876-900 75NaF/25AlP3 921 0.53 901-925 87Ha3AlP6/18MgP2

926- 950 74Na3AlF6/26CaP2 945 0.36 951- 975 33.5NaF/46.2KF/20.3MgF2 975 0.38 976- 1000 NaF 995 0.16 .394 7.97 795 2033 1001- 1025 29.5KF/70.5MgF2 1008 0.36 1026- 1050 NaMgF3 1030 0.20 .564 17.7 711 2025 1051- 1100 KMgF3 1070 0.42 2920 1251- 1300 MgF2 1252 0.24 .761 13.9 933 1301- 1500 CaF. 1418 0.11 .419 7.1 380 1448

^Based on ambient densities.

-12- Major Study Conclusions . The projected availability is shown to be adequate for widespread thermal storage use. . Costs of many metal fluorides are projected to benefit from economies of large scale production. . Thermophysical properties desirable for heat storage requirements were presented for a variety of metal fluoride compositions. . Specific metal fluoride compositions were selected as most desirable for each of 23 temperature regimes. • Metal fluorides should continue to be prime candidates for heat storage media. Recommendations . Further accelerated and real-time corrosion studies in system hardware should be carried out. . The effects of impurities on corrosion should be examined. . Wall effects, purity, and cycle life should, be evalu• ated for effects on kinetics of crystallization. . Effects of purity on thermophysical properties should be detailed. . More accurate heat transfer information should be deter• mined. . Material transfer procedures should be developed. . Thermophysical data should be determined for exception• ally interesting metal fluorides where data does not exist or is unreliable.

-13- II. INTRODUCTION At the time this study began in July, 1976, interest had blossomed in the use of high temperature heat storage as a means of attaining greater efficiency in energy production and use. Some conceptual engineering design work had been done, some experimental devices had been tested, and a variety of heat storage materials were under investigation. However, optimum choices of heat storage media for various temperature ranges had not been made and knowledge was just beginning to gel concerning trade-offs among cost factors, material proper• ties, and equipment design. One result of early studies was the recognition that metal fluorides possess many of the qualities required for storage of energy by virtue of the latent heat of fusion. In addition to latent heats on a volume basis that surpass .those of any other potentially practical material, the metal fluorides were said to have high thermal conductivities, good stabilities, low vapor pressures, and no supercooling. In particular, work done by Johann Schroder at Philips Laboratories in Aachen, Germany, had indicated that addition of a small quantity of getter material inhibited corrosion of stainless steel. Because the metal fluorides appear to be attractive candidates, several engineering studies have selected them for further investigation and development. Some questions were posed, however, that required early answers. These included questions about the future availability of metal fluorides if large, new markets were found for them. Other questions concerned the potential costs of metal fluorides if they were manufactured on a large scale. Still others centered on the apparent lack of thermophysical data for these materials. This study, consequently, was undertaken to answer these questions and to assemble the available knowledge about metal fluorides that would be useful in the material selection

-14- process. As part of this effort, we have endeavored to select the most cost-effective metal fluoride for each of a number of different temperature ranges. Our "thinking tree" for the selection process is shown in Figure I and consists of a union of technicalj cost, and availability data bases. The report, then, consists of three corresponding main sections. Some of the more voluminous support work is presented in an Appendix.

-15- FIGURE 1. METAL FLUORIDE SELECTION CRITERIA

Best Cost/Effective Fluoride Materials

Best-Technology Best-Cost Effective Materials Materials _T 1 r Technical Technical Demand/Supply Quantity & Cost Requirements Data Base Relationships Requirements I I Thermophysical Chemical Financial Availability I Data Base Evaluation Data Base Data Base

Data Alternate Selection & Opportunities Quantity Accumulation Current Costs Information

Corrosion Experimental Future Costs Source Data information Reactions Processing Costs Stabilities Transportation Costs III. APPLICATIONS Significant interest in thermal energy storage is rela• tively new and so potential applications are still being discovered and are still under review. Some of the applica• tions that have been discussed to date are given in Table I along with their required thermal storage temperature ranges. Temperature requirements extend from 4-1093°C. Perhaps higher temperature applications would be considered if suitable con• tainer materials of construction were available. With the exception of the hydrate, KF«4H20 (MP 18.5°C), the fluoride salts have attracted attention for applications in the 500- 1000°C temperature range. The data in this report cover fluorides in the 200-1400°C range.

Each application has its own set of requirements. Although high energy density, low cost, high thermal conducti• vity, low volatility, and low toxicity are commonly desired characteristics, their relative importance varies from applica• tion to application. The relationships among energy storage capacity, volume, and cost are particularly sensitive to specific application requirements: the higher the energy density/unit volume, the less volume will be required and the less equipment will be needed. Less capital will be required for the equipment, but if the high energy density medium requires a premium price, costs may be high anyway. The trade-off point is not known yet for any proposed system and an analysis of, it is beyond the scope of this study. However, data are presented in regards to energy density, volume changes, costs, corrosion, heat transfer, and other properties of metal fluorides so that systems engineers might be able to determine the applicability of fluorides for any specific application.

The data in Table I represent an effort to strike a balance between cost and effectiveness, but the more exten• sive data represented in Table I should be consulted by those interested in maximizing individual properties.

-17- TABLE I. APPLICATIONS FOR HEAT STORAGE

Temperature Range °C Function Reference 816-1093 Open Brayton, Solar Electric 220 Multiple, 38-1038 Cascaded TES - Brick Kiln 217 980-1023 Open Cycle Brayton Solar Elec• tric Power 218 990 Concentrated Photovoltaic 7 Variable, 499-982 Iron and Steel 217 550-900 Thermal Vehicles 294 312-877 Electric Resistance Heating and Cooling of Buildings 218 764-867 Closed Cycle Brayton Solar Electric Power 218 450-850 Heat Engines 294 150-850 Space Heating 295 538-816 Closed Brayton, Solar Electric 220 376-816 Solar Stirling, Electric Power 218 704-760 Gas Cooled Reactor Base Type Plant 216 427-593 Solar and Base Load Applica• tions 219 486-589 Fossil Steam, Main Steam, Electric Power Peaking 218 260-589 Solar Steam - Electric Power 218 510-579 Supercritical Steam, Base Type Plant 216 482-538 Supercritical Rankine, Solar Electric 220 260-317 Nuclear Main Steam, Electric Power Peaking 218 173-317 Fossil Steam Feed, Electric Power Peaking 218

-18- TABLE I. APPLICATIONS FOR HEAT STORAGE (Continued)

Temperature Range °c Function Reference 152-317 Feed Heat, Solar Assist Elec• tric Power 218 204-316 Steam Rankine, Solar Electric 220 93-316 Commercial/Industrial Applica• tions 219 238-271 Pressurized Water, Reactor Base Type Plant 216 232-265 Boiling Water, Reactor Base Type Plant 216 163-260 Nuclear Steam-Feed-Electric Power (Peaking) 218 34-260 Industry Waste Heat Bottoming Cycle Electric Power Generator 218 64-198 Organic Rankine Solar Electric Power 218 121-178 Rankine Air Conditioning of Building 218 121-149 Fluorocarbon Turbine Solar Electric 220 39--147 Heating and Cooling of Build- ings from Industrial or Utility Waste Heat 218 64-121 Absorption Air Conditioning of Building 218 60-100 Space Heating and Hot Water 217 82-99 Heat Storage For Input to Heat- Actuated Air Conditioner for Climate Control 215 39-96 Solar, Electric and Fossil Heating of Buildings 218 32-71 Heat Storage for Space Heating for Climate' Control . 215 18-64 Passive (Structure) Heating and Cooling of Buildings 218

-19- TABLE I. APPLICATIONS FOR HEAT STORAGE (Continued) Temperature Range °_C Function Reference 8-39 Electric or Solar Building Cooling 218 4-10 Cold Storage for Output of • - - Heat-Actuated Air Conditioner

-20- IV. AVAILABILITY The availability of metal fluorides for heat storage applications is, fundamentally, dependent on the reserves and resources of fluorine and the metals selected. The U. S. Department of Interior defines reserves as known, identified deposits of minerals that can be extracted profitably with existing technology and under present economic conditions. Resources include reserves and other deposits which may become available. The latter deposits may be known but not economi• cally or technologically recoverable at present, or they may be inferred to exist but have not yet been discovered. Also of fundamental importance are the supply-demand relationships of fluorine, the metals, and the metal fluorides. These factors will be discussed in depth, followed by an analysis of metal fluoride supply in relation to heat storage requirements.

-21- A. Fluorine Supply and Demand The relationships among sources of supply and demand for fluorine are given in Figure II. The current supply is largely composed of fluorine found in the natural mineral called fluor• spar, or fluorite, which is, chemically, the fluoride salt calcium fluoride, CaF~. The largest potential source of fluo•

rine is that found in the mineral fluorapatite, Ca5(P04)3F, the composition of phosphate rock. Recycled fluorine is con• sidered a source of fluorine because its use lessens the demand for virgin fluorine. Similarly, the use of non-fluorine mate• rials as substitutes for fluorine frees fluorine from one appli• cation, making it available for other applications. For example, use of non-fluorinated aerosol propellants would decrease the demand for fluorine and result in unused fluorine production capacity.

Other sources of fluorine are those that currently are in• significant but.that may become important, such as minerals with low percentages of fluorine requiring-new techniques of recovery. The demand for fluorine is quite widespread, because fluo• rine is used in many processes and products. By far, the larg• est portion is used in the manufacture of steel. The second prime user is the aluminum industry. The third area of use is the chemical industry, where the first conversion is to hydro• fluoric acid. Note that the production of metal fluoride salts (other than aluminum fluoride which goes to the aluminum industry) accounts for only 1.5% of fluorine consumption. If the consump• tion of metal fluorides is to be increased significantly, the required fluorine must be made available by increased supply and/or by competition with established fluorine consuming applications.

-22- Figure II. Relationships Among Sources of Supply and Demand for Fluorine1

Fluorine From Recycled Fluorspar Other Sources Phosphate Rock Fluorine

Supply

Steel 47% Aluminum 20% Hydrofluoric Acid Other 3% I to I Refrigerants *■ Stainless Steel Pickling 1.5%

Aerosols *■ Fluoride Salts 1.5% 20% Solvents > Uranium Processing 1%

Plastics * Oil Industry Catalyst 2%

Other 4%

a. Percentages indicate present fluorine consumption by the various industries as per cent of total supply. B. Fluorine Occurrence and Geology Fluorine occurs widely in nature, comprising about 0.065% of'the earth's crust. Among the elements, fluorine ranks 13th 197 in worldwide abundance. More fluorine exists than does chlor• ine. The amount of fluorine is 5-10 times greater than the amount of zinc or copper, and it is 30 times greater than lead. Because elemental fluorine is highly reactive, it occurs only in chemically combined form. More than 150 fluorine contain• ing minerals are described, but most exist only in small, widely scattered deposits or at very low concentrations. The 21 amount of fluorine in seawater is estimated at 1.9 x 10 tons but this is only 1.4 ppm. The amount of fluorine found in clay is on the order of 2000-4000 ppm. In average soil samples it is about 200 ppm. Interestingly, certain natural processes tend to concentrate fluorine. Tea plants, for example, concen• trate fluorine to 400 ppm. However, in the geological time frame, fluorine becomes progressively more highly dispersed. Great amounts of fluorine often are associated with volcanic activity. Great quantities of fluorine emanate from active volcanoes. For example, 200,000 tons/year of fluorine are liberated in the Valley of Ten Thousand Smokes in the Katmai district of Alaska. Similar amounts are liberated annually 229 from the Devils Kitchen in Hawaii. Several fluorine minerals, such as sodium tetrafluoroborate and potassium hexafluoro- silicate are often found in fumarolic deposits. In general, fluorine containing minerals occur in four ways: 1. Fumarolic deposits 2. Pneumatolytic and hydrothermal deposits 3. Accessory rock minerals 4. Pegmatitic minerals Examples of these minerals are given in Table II. Only two of these sources, calcium fluoride (CaF2) and fluorapatite (Cag-

(PO.)3F), are currently commercial sources of fluorine.

-24- Table II. Fluorine Minerals

Name. Formula Occurrence.

Villiaumite NaF In cavities in alkali rocks

Fluellite 3A1F3-4H20 H.T. hydrothermal veins

Cryolithionite Li3Na3Al2F12 In granite pegmatite with cryolite

Cryolite Na3AlF6 As above—very local

Sellaite MgF2 In dolomite rocks and fumarolic

Fluorite CaF2 In hydrothermal veins and accessory in granite rocks

Cerfluorite (Ca,Ce)F2_3 Pegmatitic mineral Matlockite PbFCl Hydrothermal lead veins

Ferruccite NaBF.4 Fumarolic

Hieratite K2SiF6 Fumarolic

Fluorapatite Ca5(P04)3F Accessory rock mineral, widespread

Fluoborite Mg3B03(F,OH)3 Hydrothermal mineral

Topaz Al2Si04(OH,F)2 Accessory in greisenized granites Cryolite (Na_AlFfi) was a commercial fluorine source for many years until the only known, significant deposit of it, located in Greenland, was depleted. Currently, calcium fluoride is the primary commercial source of fluorine. It is often very abundant in hydrothermal veins. In an area of southern Illinois - western Kentucky, calcium fluoride occurs as veins along faults, perhaps as thick as 30 feet and also in extensive flat-lying replacement-type limestone deposits. In the western states, calcium fluoride occurs as fillings in fractures and shear zones under a variety 198 of situations. This fluorine source will be discussed in greater detail below. Most of the fluorine in the earth's crust is in the form of fluorapatite, where it occurs, on the average, to the extent of 3.5% fluorine. Fluorapatite is mined in great quantities for its phosphate portion that is used for the manufacture of fertilizers. The principal producers are the United States, USSR, Morocco, Tunisia, China, South Africa and Spanish Sahara. Fluorine is recovered from this source only to a small extent, but the technology of recovery is advanced, and production only awaits the emergence of a suitable market. The production of metal fluoride salts would be a suitable market, as will be shown in following sections.

-26- C. Calcium Fluoride Supply 1. World Reserves and Resources In 1975, the identified worldwide fluorspar resources totaled 840 million tons (141 million tons F). 221 Of this, about 260 million tons (44 million tons F) are in reserves. Deposits occur on every continent and almost all industrialized nations have ready access to them. The country-by-country production figures and reserves of calcium fluoride are shown in Table III. The world production in 1974 was 5.1 million short tons but is estimated to have been only 4.9 million tons in 1975 because of reduced demand. The reduced demand of 1975 con• tinues a 4-year trend as shown in Figure III of world production statistics. This decline is partly attributable to generally unfavorable economic conditions during this period. It means that production is far below capacity, and can be increased rapidly. The reserve figures are conservative, partially because of a low level of interest in exploration. Deposits are known to exist, for example, in Alaska, Kenya, Brazil, Argen• tina, and Mongolia, but tonnage estimates have not received even cursory exploratory effort. As a consequence, further discoveries are probable, especially in third world countries where exploration has been minimal to date. In fact the history of calcium fluoride total reserves estimates is one of everupward revision. Yearly estimates made by the Depart• ment of the Interior are given in Figure IV. They show a clear trend of increasing reserves. A case in point is Mexico, which in 1927 was considered to be an unimportant source of fluorspar; which in 1952 was credited with three million tons of high-grade ore; and whose reserves are now

(1975) estimated at about 45,000,000 tons of 35% CaF2< There may well be "other Mexicos" world wide, Argentina, Brazil, China, India, etc. AS higher levels of worldwide industriali• zation occur, a greater demand for fluorine results. In

-27- Table III. World Production and Reserves of Calcium Fluoride (thousand short tons) World Mine Production and Reserves: Production Reserves (35% CaF Average 90% CaF0 or equivalent) 1974 1975 e/ United States 201 130 17,000 Canada 150 100 6,000 France 300 270 12,000 Italy 270 260 8,000 Mexico 1,226 1 ,200 45,000 South Africa, Republic of 229 300 35,000 Other Africa 84 • 110 19,000 Spain 415 400 13,000 Thailand 430 390 30,000 United Kingdom 259 190 24,000 Other Market Economy Countries 295 280 33,000 Mongolia 265 260 5,000 China, People's Republic of 300 300 13,000 U.S.S.R. 500 '500 17,000 Other Central Economy Countries 225 210 3,000 World Total 5,149 4 ,900 260,000

e = estimate Figure III. CaF2 World Production

5000 ••

4500 ■ •

a e I to 4000­■ VO u I o 6 est. •a c 3500­ ­ rt a 9 O

3000­­

2500­­

Years 2000 i 196+0 61 6+2 63 65 67 69 19Jo ­ 71 73 lt 75 Pigure IV. CaF2 Known World Reserve (35% + Concentration)

300 ••

250 •■ 09 C o H

o in I 200+ g oCO 5 I

150-.

100-•

50-•

Years f— i 196+0 61 62 63 64 65 66 67 68 69 1970 71 72 73 74 75 response, exploration, discoveries, and production are stepped up. The increased level of exploration results from a desire of third-world countries to use local resources. Yet, known reserves are already sufficient for 20 years of consumption at anticipated levels. This estimate by the U. S. Bureau of Mines has been reaffirmed for each of the past 5 years. Con• sequently, increased discoveries may result in downward price pressure. In industrialized countries, where supply sources are established and secure, there is little incentive for further exploration and so little is done. A 20-year base of supply is considered to be comfortable. Reserves are adequate to meet current and projected world needs. 221 As can be seen in Table III, the countries with greatest reserves are Mexico, the Republic of South Africa, and Thai• land. Although many people in the industry believe that the Republic of South Africa will become the dominant producing country, that role now is held by Mexico. Cheap labor and abundant, uniquely rich deposits, and a close market (the US) contribute to this dominance. Mexico's reserves lie mostly in its northern and central states, the very richest being near the Rio Grande river. See Table IV for the states in which deposits are located. These deposits, along with those of the United States and Canada, comprise 26% of all known, high quality reserves.

The production histories of Mexico and Canada are shown in Figures V and VI. Figure V shows a very high production level for Mexico, consistent over the last 7-8 years. Because the fluorine market has been small in Mexico, most of this production has been exported, principally to the US. This trend is slowing because of increased use of calcium fluoride within Mexico, both for self-use and for manufacture of fluorine-containing products for export. US firms operating in Mexico participate in this activity. Some of the companies that recently have constructed or made plans to construct

-31-

* Table IV. States of Mexico in Which Major Fluorspar , Deposits Occur

San Luis Potosi Coahuila Chihuahua Guanajuato Durango Zacatecas Guerrero Mexico Jalisco Sonora Hidalgo

-32- -ec- Figure VI. Canada Fluorspar Production (90%) 190 -

180

170 •

160

150 •

140 a 6

I 130- U U) 5 120 ■vxa eg 9 110- o

100

90-

80 •

70"-

60 Years 50 + 1— \ ■ 1960 61 62 63 64 65 66 67 68 69 1970 71 72 73 74 75 76 plants for the manufacture of hydrofluoric acid from fluor• spar in Mexico are: Industrias Quemicas de Mexico - a Stauffer affiliate Quimobasicos - an Allied Chemical Company affiliate E. I. du Pont de Nemours & Co. Minera San Francisco del Oro Financiera Bancomer Comision de Formento Minero Mexican Consortium and Continental Ore Corp. Mexican fluorine interests are protected by the Mexican Fluorite Institute (Instituto Mexicano de la Fluorita) whose objectives are to obtain and maintain production and consump• tion information on the world fluorspar'market, perform research, make projections of production and consumption, i promote sales, obtain pricing information, and assist Govern• ment authorities. In actuality, the power of this Institute^ is one of price control for the world-wide market of calcium fluoride. The Mexican manufacturers of calcium fluoride are given in Table V. Inspection of Figure VI shows the Canadian production to be low and erratic. The principal deposits are those in the St. Lawrence area of the Burin Peninsula in southern Newfound- land (see Figure VII). 231 Lesser quantities occur in Ontario, 230 British Columbia, and Nova Scotia. All of current produc• tion is carried out by Newfoundland Fluorspar, a subsidiary of Alcan Ltd. and is used for captive consumption. Canada is a net importer of fluorspar and so Canadian reserves can• not be considered to be a source for US needs. 2. US Reserves and Resources The US resources of fluorspar are estimated at 95 million tons (16 million tons of fluorine) of which 17 million tons 221 (2.9 million tons of fluorine) are reserves. The distri• bution of the reserves and resources is given in Table VI. Although Alaska, Illinois, and Tennessee hold most of the resources, most of the reserves are located in a small

-35- Table V. Mexican Producers of Fluorspar

Compania Minera Las Cuevos Miner San Francisco del Oro Compania Minera Rio Colorado Fluorita de Rio Verde Fluorita de Mexico Compania Minera la Dominica Compania Minera la Valenciana Bolanos Compania Minera La Cuesta Asarco Mexicana Minerales Pennwalt Compania Minera La Valencia Compania Minera Rio Colorado Compania Minera Los Cayos Seaforth Mineral & Ore Company Alberto Ramos Bailey Fluorspar Company Fluorspar Association Renolds Fluorspar

-36- Table VI—Fluorspar reserves and resources in the U.S. by States 1974 (Thousand short tons) Reserves Resources-Reserves Resources

State Bulk Grade CaF2 Tons Grade CaF2 Tons Grade CaF2

Alaska — — — 32,000 .17 5,440 32,000 .17 5,440 Arizona — — — 300 .37 111 300 .37 111 Colorado 2,300 .35 805 7,500 .30 2,250 9,800 .30 2,940 Idaho 3,600 .38 1 ,368 2,100 .37 777 5,700 .35 2,000 Illinois 7,000 .33 2 ,310 47,000 .15 6,970 54,000 .17 9,280 Kentucky 2,250 .37 832 4,400 .30 1,320 6,650 .31 2,061 Montana 50 .50 25 400 .38 152 450 .38 170 Nevada 300 .45 135 280 .48 134 580 .46 269 New Mexico 4,000 1,080 4*, 880 1,513 I 880 .50 440 .27 .31 Oregon — — — 12,000 .08 960 12,000 .08 960 I Tennessee — — — 50,200 .15 7,530 50,200 .15 7,530 Texas 50 .60 30 950 .44 418 1,000 .45 450 Utah 100 .63 63 900 .55 495 1,000 .56 558

*Total 16,530 .36 6 ,008 162,030 .17 27,637 178,560 .19 33,282

Rounded Figures- 17,000 .35 6 ,000 79,000 .35 28,000 95,000 .35 33,000

*Totals used by U.S. Geological Survey. Figure VII

-38- district of southern Illinois and western Kentucky. Over 4/5 of the domestic production comes from this region. As in the case of world reserves, the amount of domestic reserves varies with many factors, including the extent of exploration, rate of exploitation, etc. The US reserve esti• mates by the US Bureau of Mines are given in Figure VIII for the last several years. A significant recent development is the disclosure in 1975 by US Borax and Chemical Corporation of a new fluorspar district in Tennessee where the amounts are said to exceed 50 million tons of ore above a 20% cutoff grade. Thus, by one discovery, the reserves of the US have been more than doubled. Most: of the domestic production of fluorspar is carried out by two companies: Ozark-Mahoning/Pennwalt and Allied Chemical Corporation/Minerva. In all, 10 companies operated 16 mines during 1975 in Illinois, Kentucky, New Mexico, Nevada, Texas, and Utah. These companies and their locations are given in Table VII. Other companies who are reportedly active to varying degrees in increasing their production capacities or under• taking exploration and development programmes in various parts of the country include Du Pont, Alcoa, the American Uranium Corp., the Roberts Mining Co., Bullion Monarch, Sea• forth Mineral and Ore Co., the Ashley Company, the Tonto Mining and Milling Co., Win Industries, N. L. Industries, the Environmental Engineering and Chemical Co., Vedco Wah Wah Mines, the Bailey Fluospar Co., Burridge and Associates, J. Irving Crowell Jr. and Son, E. G. Sommerlath Enterprises, Robin Hastie and Sons, Omar Austin and Sons, Tombstone Minerals Reserve, D and F Minerals, C. E. Minerals, J. Willis Crider, Everett Crider, Kalium Chemicals, the Pom Corp., and the Lost River Mining Corporation.

A considerable amount of the domestic production is for captive markets. For example, some of Allied"s fluorspar goes to the production of hydrofluoric acid in Allied's HF

-39- Figure VIII. CaF2 Known U.S. Reserves ( 357.)

28000

26000

24000

22000

20000

I 18000' O I 16000

14000- • e

12000

10000

8000

6000

4000

Years 2000 I > i t 1960 61 62 63 64 65 66 67 68 69 1970 71 72 73 74 75 76 TABLE VII. DOMESTIC FLUORSPAR PRODUCERS BY STATE*

Colorado Ozark-Mahoning Co., Subsidiary of Pennwalt Corporation Mill and Flotation Plant on Standby Basis Allied Chemical Corporation Flotation Plant on Standby Basis Illinois Allied Chemical Corporation Industrial Chemical Division Minerva Mines Cave-In-Rocks, Illinois 62919 3 Mines 2 Flotation Plants Robin Hastie & Sons, Mine and Heavy Media Plant Ozark-Mahoning Co., Subsidiary of Pennwalt Corporation 1870 South Boulder Avenue Tulsa, Oklahoma 74119 4 Mines Flotation Plant 2 Heavy Media Plants Tamora Mining Co. Kentucky Cerro Spar Corporation Box 213, Salem, Kentucky 502-938-2771 1 Mine 1 Flotation Plant Pennwalt Corporation 2 Mines Standby Flotation Plant Montana Roberts Mining Co. Crystal Mountain Mine Output from inventory only; standby flotation plant Nevada J. Irving Crowell Beatty, Nevada 1 Mine Spor Brothers 1 Mine

*U.S. Bureau of Mines 1975 List -41- TABLE VTI. DOMESTIC FLUORSPAR PRODUCERS BY STATE (Continued) Texas D and F Minerals Eagle Pass, Texas 1 Mine Utah U.S. Energy Corporation 1 Mine Wilden Fluorspar Co. 1 Mine Spor Brothers 1 Mine' Output from inventory only New Mexico Mining and Milling Co. of America 1 Mine Standby flotation plant Arizona Tonto Basin Mining and Milling Co. 2 Mines Standby flotation plant

Note: Of the total 26 operational mines and 13 processing plants, only 16 mines and 6 plants operated in 1975. Total 1975 pro• duction capacity was 440,000 tons.

-42- facility in Claymont, Delaware. The total domestic production of fluorspar is illustrated in Figure IX. Clearly, domestic production is not a growth industry, there being less produced in 1975 than in 1961. There are several reasons for this. First of all, competition from Mexican mines is very strong. In fact, the attractive• ness of the Mexican deposits led US corporations, such as Pennwalt and Allied to open their own mines in Mexico. The Mexican deposits are, in general, of higher grade and lend themselves to surface mining techniques and so are naturally to be exploited first. As a result, many known deposits in the US will not be economically feasible to mine until the higher grade Mexican ore is depleted. For example, the Northgate, Colorado, mine of Ozark-Mahoning/Pennwalt has been closed, even though its production capacity is 50,000 tons/ year. Probably other mines in the Illinois-Kentucky region also might not be economical except for the value of the accompanying zinc and lead deposits.

Another reason for decreasing production is softness in the market. Proposed bans on the use of fluorocarbon aerosol sprays throw doubt on the market for hydrofluoric acid and consequently on the demand for fluorspar. Similarly, regulations on the emissions of fluorine by aluminum, steel, and ceramic plants have initiated efforts to trap and recycle fluorine. The steep decline in domestic production shown in Figure IX for the year 1969 is attributed to a strike in that year. The decline that began in 1973 is attributed to the reasons discussed above as well as to the closing of Ozark- Mahoning/Pennwalt Northgate Mine. Decreased U. S. production indicates the confidence that U. S. industry has that demand will be met by foreign sources. This confidence is further exemplified by the re• luctance to accumulate inventory. Stockpiles have never been high and have been reduced deliberately for the last 5 years. Of course, this phenomenon is also influenced by the drive

-43- Figure IX. CaF2. U.S. Production Finished (All Grades)

340- >

320

3004*

280

I 260+

v> I 240

220+

200

180+

160 ■

140- eat.

120.

Tears 100 ■+■ +■ . i 196+0 61 62 63 64 65 66 67 68 69 1970 71 72 73 74 75 to lower costs incurred by inventory. See Figure X. The U. S. Government also is confident about the fluorspar supply situation. The Government has examined the fluorspar supply carefully because of its strategic importance in the steel, aluminum, oil, and nuclear industries. Although the U. S. currently imports greater than 85% of its fluorspar, the 203 Council on International Economic Policy stated that "the economic effect would be slight" of any arbitrary action to increase prices by foreign governments. It concluded that "the large number of producer countries involved makes cartel• like action improbable". We believe that an additional con• clusion the council must have made is that a positive political relationship with Mexico will continue.* The U. S. stockpile currently contains an eight month supply of fluorspar at cur• rent U. S. consumption rates in excess of the strategic stock• pile objective. The stockpile was created in response to the Korean War but has never been used for strategic purposes. Sales from the stockpile have occurred (see Figure XI). An omnibus bill, submitted in March, 1973, proposed the disposal of all but 12% of the stockpile. However, in January, 1975, the Joint Committee on Defense advised against the sale of strategic materials from government stockpiles. Logic would imply that the stockpiles would be increased if fluorspar supply lines to Mexico and elsewhere were in jeopardy.

The total amounts of fluorspar imported during the past 15 years are shown in Figure XII. Currently, imports account for about 85% of consumption. Most of the imports come from Mexico, as shown in Figure XIII. Spain and Italy have also been consistent sources. The Republic of South Africa may be a significant supplier in the future. Imports from Mexico generally arrive at the following locations: Detroit El Paso Galveston

*The Mexican dominance of the current world fluorspar market is more clearly shown by recent data that was not available to the Council. -45- Figure X. U.S. Stocks • Mine 35­­

30­•

25"

e

20­• I u J i CO •a 15­ ­ a s

10 •

5­­

Years 4­ * 1 ». ■+■ i > —t— + 1970 71 74 75 76 I96 0 61 62 63 64 65 66 67 68 69 72 73 -LP-

o W o o o o o o o o o o o o o o o o o —♦— ­+­ Thousand Short Tons

vo o

?.. H­ "8 n a a X H <7< ON.

00 •s »1 on ' O O

«4

Ji­

Vn Figure XII. U.S. Imports 1400 + 1. Acid - spar (97X +) 2. Met - spar (97Z -) 3. Total 1300

1200 ■•

1100 est.

lOOOf

900 d

800 I 8 00 I 700 ■a est. a CO S 600" 6

500

400-* est.

300

200 +

100 •

Years 0 -4 1 h + 1 i 1 ■ I 1960 61 62 63 64 65 66 67 73 74 75 68 69 1970 71 72 ZL ZL U 0£61 69 L9 59 t79 C9 29 19 096T I " i ­£­ —«—■ « ­+­ —•—< ■+­ —I— ­+­ s«sx.

' 0

01

­ 02

OG

­ Of

•0 OS I B ­ 09 i

01

. 08

06

• 001 231130 ■ 0 *IB3I ­ I ufBds ­ S on OJTfXSW m M

1178700 30 Xaaunoo Xq ssaodmi •s'fl *IIIX 9xnBji Honolulu Houston Laredo Brownsville Los Angeles New Orleans Nogales Philadelphia San Diego Baltimore Buffalo Cleveland Detroit Even though the percentage of fluorspar imports seems large, even greater percentages of the following raw materials are imported:

Aluminum Mica Asbestos Manganese Chromium Strontium Cobalt Tantalum Columbium Tin Finally, the available supply is very much dependent on the market price. When prices increase faster than costs, marginal mines come on stream. Higher prices allow process• ing of lower grade ore and permit establishment of mills at locations where deposits are not now large enough to support mills. Increased prices also cause individual Mexicans to collect and bring in much more spar.

-50- \ D. Fluosilicic Acid Supply

The mineral fluorapatite, Ca., Q (POJ gF2, is the main com­ mercial source of phosphate. In processing, this mineral is digested by an acid such as sulfuric acid:

Ca1Q(P04)6F2 + 10H2SO4 ■» 10CaSO4 + 6H3P04 + 2HF

The liberated hydrofluoric acid readily combines with the available silica to give silicon tetrafluoride, which reacts with water to give an aqueous solution of fluorosilicic acid. Neutralization with an inexpensive alkali can give low cost metal fluoride compounds.

MF SYNTHESIS

H2S04 SiO, Ca (PO ) F HF > SiF, 10 4 6 2 ­^­^

H2SiF6

NH.F Na2SiF6 4 V^.M^0 M2C03

1 MpM Oo or CO^^2 ^

0H r M C0 HF ** ° 2 3 M­A1FC 3 6

Thus the fluorine byproduct can be recovered as metal fluorides by scrubbing and subsequent reaction of the gases evolved during phosphate manufacture. The amount of fluorine in the gases depends on the process used (for example, phosphoric acid can be used for digestion instead of sulfuric acid) and on the quality of phosphate rock. In the U.S., phosphate rock contains 2­5% fluorine (3.5% average (of which 35­50% is volatilized in the manufacture of wet­process phosphoric acid.

­51­ In the manufacture of normal superphosphate, 11-42% of the fluorine in the phosphate rock is volatilized (21.4% average), whereas for triple superphosphate only ~4% fluorine is evolved. In general, 95% of the evolved fluorine can be recovered as

H2SiFfi. Taking these considerations into account, the U.S. Bureau of Mines reported that 295,000 tons (590,000,000 pounds) per year of fluorine could be recovered from U.S. phosphate plants if a suitable market for the fluorine existed. This represents about 20% of the fluorine annually available if complete recovery would be achieved. By the year 2000, the study projected that 500,000 - 800,000 tons (1 to 1.6 billion pounds) per year to be available. The weight of metal fluor• ides that could be prepared from this fluorine is much larger than these figures, and would depend on the atomic weights of .. . . 204-208 the metals. The most significant phosphate deposits and the largest phosphate production plants in the U.S. are located in Florida, Mississippi, North Carolina, Tennessee, Utah, and Virginia. The total U.S. phosphate deposits are estimated at 7.0 billion tons. This would represent 245 million tons of fluorine. By comparison, the current U.S. production rate is 46 million tons of phosphate rock per year. Some of the companies in• volved in phosphate production are listed in Table VIII. Process development continues by the Bureau of Mines and others to improve the phosphate digestion and increase the fluorine recovery. Recent studies indicate that digestion of the rock with phosphoric acid instead of sulfuric acid may result in 80% recovery of fluorine, as opposed to less than 20%.

Recovery of fluorine from this source began in the U.S. in 1964 and has grown to the recovery rate of 46,000 tons/year (see Figure XIV). This represents 44% of total fluorine production and about 6% of consumption in the U.S. Most of fluorine is sold as fluosilicic acid for water treatment

(40%) or as AlF, and Na,AlFc (60%) for use as an electrolytic

-52- Table VIII. Some Companies Involved in Phosphate Production

Phosphate Rock Annual Capacity (Thousands of Tons)

Beker Indust. Corp. Conda, Idaho 1600 Borden Inc. Borden Chem. Div. Smith-Douglass Teneroc, Fla. 800 Brewster Phosphates Bradley, Fla. 3300 Lonesome Mine, Fla. 3000 Cominco American Inc. Garrison, Mont. 350 Cuyama Phosphate Co. New Cuyama, Calif. 300 Esmark, Inc. Swift Agricultural Chems. Corp. Silver City, Fla. 2000 I Watson, Fla. 900 u> l Freeport Minerals Co. Freeport Phosphate Rock Co., div. Fort Meade, Fla. Gardinier, Inc. U.S. Phosphoric Products Fort Meade, Fla. 2000 W. R. Grace & Co. Agricultural Chems. Group Bartow, Fla. 2300 Internat'l Minerals & Chem. Corp. Agricultural Operations Clear Springs, Fla. 2500 Kingsford, Fla. 5000 Noralyn, Fla. 5000 Jon-T Chem. Inc. Jon-T Phosphates Leslie, Ark. 6 Meramec Mining Co. Sullivan, Mo. 50 Mobil Oil Corp. Mobil Chem. Co., div. Phosphorus Div. Fort Meade, Fla. 3500 Nichols, Fla. 1500 Table VIII. Some Companies Involved in Phosphate Production (Cont'd) Phosphate Rock (Cont'd) Annual Capacity (Thousands of Tons) Monsanto Co. Monsanto Indust. Chems. Co. Columbia, Tenn. 1500 Soda Springs, Idaho 1000 Occidental Petroleum Corp. Hooker Chem. Corp., subsid. Hooker Chems. and Plastics Corp. subsid. Electrochemical and Specialty Chems. Div. Columbia,'Tenn. 500 Occidental Chem. Co., subsid. Florida Operations Swift Creek, Fla. 2000 White Springs, Fla. 3000 Rocky Mountain Phosphate Co. Powell City, Utah 20 I J. R. Simplot Co. Minerals and Chem. Div. Conda, Idaho 600 Gay, Idaho 2000 Stauffer Chem. Co. Fertilizer and Mining Div. Crawford Mines (Rich County), Utah 1000 Leefe, Wyo. ] Vernal, Utah 800 Wooley Valley, Idaho 500 T-A Minerals Inc. South Mulberry, Fla. 500 Tennessee Valley Authority Franklin, Tenn. 170 Texasgulf Inc. Agricultural Div. Aurora, N. C. 2500 United States Steel Corp. USS Agri-Chemicals Div. Fort Meade, Fla. 2000 The Williams Companies Agrico Chem. Co., subsid. Orange Park, Fla. Mulberry, Fla. 8500 Payne Creek, Fla. TOTAL 60696 Table VIII. Some Companies Involved in Phosphate Production (Cont'd) Ortho-Phosphoric Acids

Annual Capacity (Thousands of Tons)

Allied Chem. Corp. Union Texas Petroleum Div. Agricultural Dept. Geismar, La. 160 Beker Indust. Corp. Conda, Idaho 250 Hahnville, La. 215 Marseilles, 111. 105 Borden, Inc. Borden Chem. Div. Smith-Douglass Piney Point, Fla. 165 Streator, 111. 20 CF Indust. Inc. Bartow Phosphate Complex Bartow, Fla. 650 Plant City Phosphate Complex Plant City, Fla. 625 i Engelhard Minerals & Chems. Corp. Conserv. Inc., subsid. Conserv. Chems. Div. Nichols, Fla. 130 Farmland Indust., Inc. Green Bay, Fla. 475 First Mississippi Corp. FIRSTMISS INC., subsid. Fort Madison, Iowa 225 FMC Corp. Chem. Group Indust. Chem. Div. Carteret, N. J. Green River, Wyo. Lawrence, Kans. 400 Newark, Calif. Freeport Minerals Co. Freeport Chem. Co., div. Uncle Sam, La, 750 Gardinier, Inc. U. S. Phosphoric Products Tampa, Fla. 495 Gardinier Big River, Inc. Helena, Ark. 50 Table VIII. Some Companies Involved in Phosphate Production (Cont'd) Ortho-Phosphoric Acids (Cont'd) Annual Capacity (Thousands of Tons) Goodpasture, Inc. Brownfield, Tex. 35 W. R. Grace & Co. Agricultural Chems. Group Bartow, Fla. 330 Hydrite Chem. Co. Mi lwaukee, Wi sc. 8 Internat'l Minerals & Chem. Corp. IMC Chem. Corp., subsid. New Wales, Fla. 800 Kerr-McGee Corp. Kerr-McGee Chem. Corp., subsid, Trona, Calif. 5 Mississippi Chem. Corp. Pascagoula, Miss, 150 Mobil Oil Corp. I Mobil Chem. Co., div. tn ON Phosphorus Div. Depue, 111". 120 l Fernald, Ohio 35 Monsanto Co. Monsanto Indust. Chems. Co. Augusta, Ga. 45 Carondelet, Mo. 65 Kearny, N. J. 90 Long Beach, Calif. 80 Trenton, Mich. 190 North Idaho Phosphate Co. Kellogg, Idaho 30 Occidental Petroleum Corp. Hooker Chem. Corp., subsid. Hooker Chems. and Plastics Corp. subsid. Electrochemical and Specialty Chems. Div. Dallas, Tex. 45 Godwin, Tenn. 25 Jeffersonville, Ind. 35 Occidental Chem. Co., subsid. Florida Operations White Springs, Fla. 575 Western Div. Lathrop, Calif. 40 Table VTII. Some Companies Involved in Phosphate Production (Cont'd) Ortho-Phosphoric Acids (Cont'd) Annual Capacity (Thousands of Tons) Olin Corp. Agricultural Chems. Div. Pasadena, Tex. 300 Indust. Products and Services Div. Joliet, 111. 130 Pennzoil Co. Pennzoil Chem. Inc., subsid Hanford, Calif. 20 Royster Co. Mulberry, Fla. 135 J. R. Simplot Co. Minerals and Chem. Div. Pocatello, Idaho 225 Stauffer Chem. Co. Fertilizer and Mining Div. Pasadena, Tex. 60 Salt Lake City, Utah 65 I Indust. Chem. Div. Chicago, 111. 20 in Chicago Heights, 111. 80 l Morrisville, Pa. 60 Nashville, Tenn. 20 Richmond, Calif. 20 Silver Bow, Mont. 20 South Gate, Calif. 35 Tennessee Valley Authority Muscle Shoals, Ala. 85 Texasgulf Inc. Agricultural Div. Aurora, N. C. 680 Union Oil Co. of California Collier Carbon and Chem. Corp. subsid. Nichols, Calif. 8 United States Steel Corp. USS Agri-Chemicals Div. Bartow, Fla. 90 Fort Meade, Fla. 180 Valley Nitrogen Producers, Inc. Helm, Calif. 46 A F C Co., subsid. Bena, Calif. 7 The Williams Companies Agrico Chem. Co., subsid. Bartow, Fla. 340 Donaldsonville, La. 400 Note: Capacity data are in thousands of short tons of P-,0,. content. TOTAL 10444 Table VIII. Some Companies Involved in Phosphate Production (Cont'd) Super- or Poly- Phosphoric Acids Annual Capacity (Thousands of Tons) Allied Chem Corp. Union Texas Petroleum Div, Agricultural Dept. Geismar, La. 127 Farmland Indust., Inc. Green Bay, Fla. 117 FMC Corp. Chem. Group Indust. Chem. Div. Carteret, N. J. n.a. Lawrence, Kans. n.a. Newark, Calif. n.a. Goodpasture, Inc. -Brownfield, Tex. 30 Internat'l Minerals & Chem. Corp. I in Agricultural Operations Bonnie, Fla. 180 oo i North Idaho Phosphate Co. Kellogg, Idaho 11 Occidental Petroleum Corp. Hooker Chem. Corp., subsid. Occidental Chem. Co., subsid. Florida Operations White Springs, Fla. 105 J. R. Simplot Co. Minerals and Chem. Div. Pocatello, Idaho 55 Stauffer Chem. Co. Fertilizer and Mining Div. Pasadena, Tex. 22 Salt Lake City, Utah 34 Indust. Chem. Div. Chicago, 111. n.a. Richmond, Calif. n.a. Silver Bow, Mont. n.a. Tennessee Valley Authority Muscle Shoals, Ala. 85 Texasgulf Inc. Agricultural Div. Aurora, N. C. 248 Valley Nitrogen Producers, Inc. Helm, Calif. 50 TOTAL 1064 Table VIII. Some Companies Involved in Phosphate Production (Cont'd) Normal Super Phosphate Capacity Tons per Day Alabama Farmers Cooperative, Inc. Selma, Ala. n.a. American Plant Food Corp. Galena Park, Tex. MOO Borden Inc. Borden Chem. Div. Smith-Douglass Che s apeake, Va. n.a. Streator, 111. n.a. Burley Belt Chem, Co., Inc. London, Ky. 240 Columbia Nitrogen Corp. Moultrie, Ga. 315 Enserch Corp. Nipak, Inc., subsid. Littlefield, Tex. 140 l Esmark, Inc. Swift Agricultural Chems. Corp. Bartow, Fla. 300 l Birmingham, Ala. 600 Charleston, S. C. 550 Dothan, Ala. 700 Norfolk, Va. 600 Savannah, Ga. 190 Wilmington, N. C. 500 Gardinier, Inc. U. S. Phosphoric Products Tampa, Fla. 600 Gold Kist Inc. Clyo, Ga. 400 Cordele, Ga. 400 W. R. Grace & Co. Agricultural Chems. Group Charleston, S. C. n.a. Columbus, Ohio n.a. Joplin, Mo. n.a. Nashville, Tenn. n.a. Indiana Farm Bureau Cooperative Association, Inc. Indianapolis, Ind. 400 Table VIII. Some Companies Involved in Phosphate Production (Cont'd) Normal Super Phosphate (Cont'd) Capacity Tons per Day Internat'l Minerals & Chem. Corp. Chem. Group Rainbow Div. Americus, Ga. 230 Florence, Ala. 400 Hartsville, S. C. 400 Spartenburg, S. C. 400 Kaiser Aluminum & Chem. Corp. Kaiser Agricultural Chems. Div. Riegelwood, N. C. 600 Kerr-McGee Corp. Kerr-McGee Chem. Corp., subsid. Baltimore, Md. 500 Cottondale, Fla. 500 Jacksonville, Fla. 500 Philadelphia, Pa. 500 l o Layco Chem. Co. Pierce, Fla. 200 I Mineral Fertilizer Co. North Salt Lake, Utah n.a. Occidental Petroleum Corp. Hooker Chem. Corp., subsid. Occidental Chem. Co., subsid, Western Div. Lathrop, Calif. 395 Richmond Guano Co. Richmond, Va. ' 160 Royster Co. Athens, Ga. 150 Chesapeake, Va. 300 Southern States Phosphate & Fertilizer CO. Savannah, Ga. n.a. Stauffer Chem. Co. Fertilizer and Mining Div. Tacoma, Wash. 300 Texaco Inc. Federal Chem. Co., subsid. Columbus, Ohio n.a. Nashville, Tenn. n.a. Omaha, Neb. n.a. Table VIII. Some Companies Involved in Phosphate Production (Cont'd) Normal Super Phosphate (Cont'd) Capacity Tons per Day United States Steel Corp. USS Agri-Chemicals Div. Albany, Ga. 175 Chicago Heights, 111. 500 Columbus, Ga. 200 Greensboro, N. C. 200 Nashville, Tenn. 400 Wilmington, N. C. 400 Valley Nitrogen Producers, Inc. A F C Co., subsid. Bena, Calif. 300 Agriform of Imperial Valley, subsid, Imperial, Calif. 400 Weaver Fertilizer Co., Inc. Norfolk, Va. n.a. The Williams Companies I Agrico Chem. Co., subsid. Greensboro, N. C. 150 Saginaw, Mich. 300 TOTAL 14895 Table VIII. Some Companies Involved in Phosphate Production (Cont'd) Triple Super Phosphate Annual Capacity (Thousands of Tons) Beker Indust. Corp. Conda, Idaho 340 Borden Inc. Borden Chem. Div. Smith-Douglass Piney Point, Fla. 70 CF Indust., Inc. Plant City Phosphate Complex Plant City, Fla. 930 Engelhard Minerals & Chems. Corp. Conserv. Inc., subsid. Conserv. Chems. Div. Nichols, Fla. 280 Farmland Indust., Inc. Green Bay, Fla. 200 Gardinier, Inc. i U. S. Phosphoric Products Tampa, Fla. 745 CO I W. R. Grace & Co. Agricultural Chems. Group Bartow, Fla. 665 Joplin, Mo. 100 Internat'l Minerals & Chem. Corp. Agricultural Operations Bonnie, Fla. 300 Mississippi Chem. Corp. Pascagoula, Miss. 300 Occidental Petroleum Corp, Hooker Chem. Corp., subsid. Occidental Chem. Co., subsid. Florida Operations White Springs, Fla. 460 Royster Co. Mulberry, Fla. 210 J. R. Simplot Co. Minerals and Chem. Div. Pocatello, Idaho 120 Stauffer Chem. Co. Fertilizer and Mining Div. Salt Lake City, Utah 35 Texasgulf Inc. Agricultural Div. Aurora, N. C. 500 Table VTII. Some Companies Involved in Phosphate Production (Cont'd) Triple ier Phosphate (Cont'd) Annual Capacity (Thousands of Tons) United States Steel Corp. USS Agri-Chemicals Div. Fort Meade, Fla. 295 The Williams Companies Agrico Chem. Co., subsid. Bartow, Fla. 675 TOTAL 6225 Figure XIV. U.S. Fluorspar Equivalent From H-SiF,

100

90

80

03 C 70 o H 4J U O 60 £. in T> I C (0 50 CO o H 40

30 -

20 -

10

1971 1972 1973 1974 1975 1976

Year flux by the aluminum industry. The companies known to be engaged in fluosilicic acid recovery and conversion are given in Table IX.

-65- Table IX. Some of the Companies Involved in Fluosilicic Acid Recovery and Conversion

Aluminum Fluoride Aluminum Corporation of America Fort Meade, Florida Hydrofluosilicic acid (Fluosilicic acid) (Hexafluorosilicic acid) (Silicofluoric acid) Burley Belt Chem. Co. Inc. London, Ky. Chemtech Indust., Inc. Fluoride Mfg. Div. East St. Louis, 111. Essex Chem. Corp. Chems. Div. Paulsboro, N. J. Gardinier, Inc. U. S. Phosphoric Products Tampa, Fla. Gold Kist Inc. Clyo, Ga. Cordele, Ga. W. R. Grace & Co. Agricultural Chems. Group Bartow, Fla. Columbus, Ohio Joplin, Mo. Nashville, Tenn. Internat'l Minerals & Chem. Corp. Chem. Group Rainbow Div. Americus, Ga. Florence, Ala. Fort Worth, Tex. Hartsville, S. C. Spartanburg, S. C. Kaiser Aluminum & Chem. Corp. Kaiser Agricultural Chems. Div. Riegelwood, N. C. Kewanee Indust., Inc. Harshaw Chemical Co., subsid. Indust. Chems. Dept. Cleveland, Ohio Olin Corp. Indust. Products and Services Div. Joliet, 111. USS Agrichemicals Div. of U.S. Steel Corp. Fort Meade, Fla. -66- Table IX. Some of the Companies Involved in Fluosilicic Acid Recovery and Conversion (Cont'd)

Hydrofluosilicic acid (Cont'd) Pelham Phosphate Co. Pelham, Ga. Texasgulf Inc. Agricultural Div. Aurora, N. C. The Williams Companies Agrico Chem. Co., subsid. Baltimore, Md. Bartow, Fla. Magnesium silicofluoride (Magnesium fluorosilicate) The Williams Companies Agrico Chem. Co., subsid. Bartow, Fla. Potassium silicofluoride Borden Inc. Borden Chem. Div. Smith-Douglass Chesapeake, Va. Streator, 111. Kawecki Berylco Indust., Inc. Boyertown, Pa. The Williams Companies Agrico Chem. Co., subsid. Pensacola, Fla. Sodium fluosilicate (sodium silicofluoride) Chemtech Indust., Inc. Fluoride Mfg. Div. East St. Louis, 111. Columbia Nitrogen Corp. Moultrie, Ga. Essex Chem. Corp. Chems. Div. Paulsboro, N. J. Gardinier, Inc. U. S. Phosphoric Products Tampa, Fla. Kaiser Aluminum & Chem. Corp. Kaiser Chems. Div. Mulberry, Fla.

-67- Table IX. Some of the Companies Involved in Fluosilicic Acid Recovery and Conversion (Cont'd)

Sodium fluosilicate (Cont'd) Olin Corp. Indust. Products and Services Div. Joliet, 111. The Williams Companies Agrico Chem. Co., subsid. Donaldsonville, La.

-68- E. Other Fluorine Sources The recovery of fluorine from most of the fluorine con• taining minerals, as represented in Table II, has not been considered to be economical. However, some of these minerals are processed for their metal .content, and although the through• put is much smaller than the phosphate industry, the fluorine by-product air pollution problem is similar. Air pollution regulations may require installation of scrubbing systems that would collect and concentrate the fluorine. Thus, the pro•

cessing of lepidolite, (K,Li)2A12(SiCO (F,OH)2, amblygonite,

LiAl(F,OH)P04, topaz, Al2Si04(F,OH)2, and bastnaesite, (Ce,La)2~

Ffi*(Ce,La)?C0^ may result in fluorine values. For example, the Molybdenum Corporation of America generates and vents 3 to 4 tons of fluorine per day as a mixture of SiF. and HF at its bastnaesite mining and refining operations in Southern Califor• nia. This ore body is estimated at 10 million tons, containing 1,000 tons of fluorine. Appreciable quantities of fluorine are volatilized in the manufacture of glass and enamel. Zinc smelting operations evolve fluorine, and, of course, so do aluminum, magnesium, and steel plants. Much of the fluorine volatilized at alumi• num plants in the United States is now recovered and recycled within the plants, as a result of environmental restrictions. Few controls, however, have yet been enforced on steel plant emissions. The problems are economic, not technical: A fume cleaning unit was installed on a U.S. Steel Company plant in Provo, Utah, that converts the gaseous fluorine to calcium fluoride by injection of calcium hydrates and carbonates into the gas stream. About 4 tons/day of fluorine are collected 197 in this way. Similarly, fluorine may be collected in the future from the plant exhausts for the manufacture of brick, tile, refrac• tory, pottery, stoneware, lime, and cement. Many coals contain more than 80 ppm of fluorine, and some coal shales

-69- contain up to 460 ppm of fluorine. During coal combustion, HF and metal fluorides may be liberated, contributing to the corrosion of equipment and pollution of the atmosphere. National emphasis on the production of great quantities of clean energy from coal may result in recovery of these fluor• ine values. Very large tonnages of fluorine are involved, although the initial concentration is low. Currently, both natural and synthetic fluorspar are dumped from industrial operations, such as at the Shippingport, Penn• sylvania, Atomic Power Plant and various mine tailing dumps from lead, zinc, and other metals workings. A significant, but classified amount of waste fluorine is generated in the processing of uranium. After uranium oxide is mined, purified, and concentrated, it is converted to uranium tetrafluoride by reaction with hydrofluoric acid. A sequential step with elemental fluorine converts the product to uranium hexafluoride:

uo2 -S£> UF4 -^2-> UF6 235 Because the UF, is composed of 0.76% U and 99.24% of in- active U 238 , these two materials are then separated. The inactive U 238F , is disposed of, representing a potential source of fluorine. The lesser amount of active U 235 is converted back to U02 or U to be used for weapons or power production. Some reconversion reactions are:

235 235 U Fg + C ->• U F4 + CF4 235 235 J U F4 + 2Mg -*• U + 2MgF2 The fluorinated carbon and magnesium fluoride materials are wastes and also represent potential sources of fluorine 238 values. Obviously, the amount of waste U Fg is large rela• tive to the amounts of waste CF and MgF0 and to the amount of 235 active U produced. The quality, handling hazards, and possibilities of utilization within Governmental operations are not known by us.

-70- F. Fluorine Demand The over-all demand picture for fluorine was previously presented in Figure II. It was shown that most fluorine goes to the steel, aluminum, and chemicals industries. In degree of usefulness, fluorine in the form of calcium fluoride, is essential to the steel, glass, ceramic, and cement industries. As hydrofluoric acid, fluorine is essential to the chemical, aluminum, oil, and nuclear industries. Consumption trends depend directly on the growth of these industries, but are subject to technological changes within these industries. Both in form and quantity, fluorine has found an ever increasing number of new commercial uses. In some areas this has been due largely to the economy of use: • Fluorine continues to be in relatively abundant supply domestically and worldwide. • Fluorine in mineral form is relatively inexpensive. • Fluorine, in its direct uses for processing commo• dities (steel, aluminum, ceramics), is relatively insignificant in cost relative to the value of the end product. In other areas of use the unusual properties of fluorine tend to offset the economic considerations. This is particularly true of the "converted" forms of fluorine such as fluorocarbon aerosols and refrigerants, HF, fluoroplastics, F , etc. The per• formance of fluorine in such cases is based on one or more of the following: • Energy Release Elemental fluorine is highly energetic and will react with almost all of the elements to form compounds with very strong bonds. In the pro• cess, tremendous oxidizing power is provided that can be used for propulsion, cutting, etc.

-71- • Chemical and Physical Stability Examples are fluorine-containing plastics and SF, type dielectrics. • Fluxing and Solvency Properties Fluoride salts, regardless of form, effectively lower the viscosity of slags (magnesium, etc.) and the viscosity of melts (glass and other ceramics). Although not essential, these fluoride salts are in widespread use. On the other hand, fluoride (as synthetic or natural cryolite) is essential for aluminum production. Here cryolite is the only effective solvent for alumina. Interestingly, in none of these uses (steel, magnesium, aluminum), is there any true consumption of fluorine values. All are processing wastes and to an extent availa• ble for recovery.

• Other Unique Properties Here fluorine has therapeutic value as in water fluoridation, synthetic blood, and in certain drugs. Also, through combination with fluorine are some other materials converted to additional useful forms. Uranium ore and chlorocarbons are examples. The consumption of fluorine in .the U.S. has outpaced con• sumption in other countries. Currently, the U.S. accounts for about 26% of the world's total fluorine consumption, although it produces only 3% of world demand. The historical growth curve for fluorine consumption by the United States is shown in Figure XV. Consumption vs. imports is given in Figure XVI. The leveling of consumption shown for the past year accen• tuates the major uncertainties in the current demand picture. In addition to the effects due to general economic slowdown, this dip in demand reflects changes in the aluminum and aerosol

-72- Figure XV. U.S. Fluorspar, Consumption (All Grades)

1800

1600

to 1400 c o H u 1200 o I •vl CO CO I c 1000 CO CO 3 o H 800

600

400 -

200

1920 1930 1940 1950 1960 1970 1980

Year Figure XVI. U.S. Fluorspar Consumption and- Imports

2000

Consumpti y "-""■"' Imports 1000

700

500

300 co c o H 200 - U o CA *o c 100 CO CO 3 O .e H 50

20

l i ..... i • i 1940 1945 1950 1955 1960 1965 1970 1975 Year

-74- industry consumption and may foretell further softness in these markets. Yet, the US Bureau of Mines prediction is for the historical growth rate of consumption to continue (see Figure XV). The major markets for fluorine now will be examined indi­ vidually: ■ 1. Fluorine Demand ­ Steel Production In steelmaking, pig iron and iron scrap are used as the source of iron. Pig iron contains impurities, including the elements carbon, manganese, phosphorus, sulfur, and silicon that must be removed before the steel can be made. There aire a number of techniques for making steel, but in all of these processes, chemicals must be added in order to remove the impurities from the iron. The silicon, manganese, and phosphorus are converted to their oxides and then dissolved in the slag. Lime, as one ingredient of the slag, reacts with the sulfur impurity to form calcium sulfide which also dissolves in the slag. Fluorspar is used as the principal ingredient of the slag and acts as a flux. In the molten state, this metal fluoride promotes rapid formation of a fluid reactive slag that accomplishes desulfurization and dephosphorization. Approximately 6.5 lb of fluorspar are required to make one ton of steel.

Presently, the two main processes used for steel production in the United States are the Basic Open Hearth (BOH) process and the Basic Oxygen (BO) process. Both use fluorspar as the optimum cost­effective flux. The BO process is displacing the BOH process, and because it requires two to three times as much fluorspar, there is a steadily increasing demand by the steel industry for this commodity. At present, this demand requires 47% of the entire US fluorspar market. The histori­ cal growth curve and trend projections for the use of fluorine in steel production are shown in Figure XVII.

­75­ Figure XVII. Historical Demand and Trend Projections of Fluorine Used in Steel Production

'rojec- tion High

- «-• Low

2000 Year

-76- The commitment of the steel industry to a process which requires more, rather than less, fluorspar reflects either con• fidence in the future supply and availablility of fluorspar or knowledge that suitable substitutes exist. Indeed, certain amounts of fluorspar are replaced routinely in both processes by a variety of materials. In each process, the unit consumption of fluorine is decreasing, but the pre• sence of some fluorine is not generally entirely eliminated in the US. There is continuing research to find suitable, more environmentally acceptable substitutes, but all of them are either less effective and/or more costly. Nevertheless, their existence tends to stabilize the price of fluorspar, because if the price of fluorspar were to be raised relative to the substitutes, then a greater percentage of the substitutes would be used, reducing the demand for fluorspar. This cost-sensitivity would also play a role if a large new demand for fluorspar were created. As the price of fluor• spar would rise the steel industry would limit its fluorspar useage leveling the over-all demand. This stimulus-response mechanism would dampen price increases. In any case, because of the investment in conventional steel plants, the use of fluorspar in the steel industry is likely to remain substantial through the year 2000. The degree of air pollution enforcement is critical to the extent to which substitution for fluorspar is carried. It should be noted that in West Germany, very little fluorspar is used at all in their open hearth furnaces. The reason little is used is to control the fluorine emissions in the stack gases. Clearly, there is potential for decrease in fluorine demand from this industry. 2. Fluorine Demand - Aluminum Production Presently, the dominant process for the production of aluminum is the Hall route, in which alumina is dissolved in

-77- molten cryolyte, Na3AlFg, and electrolyzed. This process re• quires addition of aluminum fluorides because of the constant emissions of fluorine bearing particulates and gases. The flow of fluorine for the aluminum industry is illustrated in Figure XVIII. The demand for merchant fluorine by the aluminum industry is a function of the following criteria: 1. Aluminum production 2. Fluorine recycling 3. New, captive sources of fluorine 4. Replacement of the Hall process with other processes that do not require fluorine. Aluminum production is coupled to demand so that a de• crease in annual production is possible and in fact occurred 209 in 1975. Over the long range, annual production should increase, possibly at the 5.1-7.7% rate predicted by the * «• 210 Bureau of Mines. The fluorine emissions from the electrolytic cells used in the Hall process are, to a greater and greater extent, being salvaged and recycled. The incentive is governmental pollution controls. The net result is a reduction in the amount of virgin fluorine required for a given quantity of aluminum produced. Several processes for the conversion of fluosilicic acid to aluminum fluoride and cryolyte have been developed and are in use. These processes are economically competitive and cost-effective for producing these metal fluorides so that the aluminum industries have set up plants to convert the waste fluorosilicic acid for their own captive use. This new substitute fluorine source supplied about 36,000 tons of fluorine to the aluminum industry in 1974, and is expected to increase in the future, thereby decreasing the demand for fluorspar fluorine supplies.

-78- Figure XVIII. fZuoe/rt£ V4tu£$ //Y r#£ /HUM/HUM /nousr/ey

/VATC/PAL PHOSPMATS £OC< JC/0 PLUOPSPAP

f V4LU£S

i i J/fj C*yoi/T£ Cxyo£/7f 4/f\

X/tscovejtr ! SecoMOijrr i ! PX/MA/ty L -rzrg

All/ft/HUM Another new development that will decrease the demand for fluorspar fluorine supplies is a new, energy-saving process for aluminum production that does not use fluorine at all, but in- 212 stead converts alumina to aluminum chloride that is then electrolyzed to give aluminum. A new plant using this process has been built in Texas and, if successful, threatens the domi• nation of the Hall process. Other possible processes are also under investigation because of the increasing scarcity of high grade bauxite and the high energy requirements of the Hall process. 213 As a result of these new activities, the consumption of fluorine in the aluminum industry cannot be related directly to aluminum production. Prediction of future fluorine use is therefore unusually difficult to make. Nevertheless, the historical demand and trend predictions are presented in Figure XIX. 3. Fluorine Demand - Fluorocarbon Production Fluorocarbons comprise a class of materials that contain both fluorine and carbon, and may also contain other atoms. They vary widely in properties and are used mostly as aerosol propellants, refrigerants, plastics, solvents, and blowing agents. The fluorine for these products is supplied by hydro• fluoric acid, which is derived from calcium fluoride and can be obtained from fluosilicic acid. The rapid growth in use of these products since World War II has created a substantial demand for fluorine. In 1974, 157 thousand tons of fluorspar were required, or 10% of total fluorine demand. The historical growth rate figures and projected trends for F compounds are given in Figure XX; however, great uncertainty must be placed on the future trends. During the past two years, a controversy has developed over alleged effects on the atmosphere's ozone layer by the low molecular weight fluorochlorocarbon products used as aerosol propellants. The National Academy of Sciences, the Environmental Protection Agency, and the Food and Drug

80- +cJ CI £ 1000 S 900 g 800 "g 700 P £ 600 n 500 - c +> M 400 - O

o 300 - CO •o c 10 CO 3 O 6 200

1960 Year

Figure XIX. Projections of Fluorine Use in the Aluminum Industry

-81- Projec­ tion

*} '> High c 900 ■0p1 a 800 o 700 01 Low ■rct 600 o 3 fa 500 n 1 400 t! O 6 300

2000

Figure XX. Historical Demand and Trend Predictions of Fluorine Used in Chemical Production

­82­ Administration and the Consumer Product Safety Commission have expressed concern over these products, and the potential for restrictions on their production seems high. Since the per• centage of all fluorine consumed that goes into the manufacture of these propellants is 10%, 75 short tons of fluorine, may, theoretically, become available for other uses, such as the manufacture of metal fluorides. 4. Fluorine Demand - Other Applications The demand for hydrofluoric acid used for uranium enrich• ment and as a petroleum alkylation catalyst is expected to grow, but this growth is not likely to exceed 10% of the HF market, or about 4% of the total F demand. Exports of finished fluorine containing products will probably continue at the historical level, about 1 % of F demand. The ceramics demand for fluorine has been declining as depicted in Figure XXI.

Some of the chemicals that are used in this industry are CaF2,

HF, Na„SiFfi, and K2SiF,. In addition to the aluminum fluorides used in the aluminum industry, a large number of inorganic - fluoride salts are produced for use in water fluoridation, insecticides, fungicides, fluxing agents, laundry sours, electro- tinning of steel, organic synthesis catalysts, epoxy hardener accelerators, electropolishing of aluminum, tooth decay pre• ventatives, stainless steel pickling, and glass etching. Calcium fluoride is also used in abrasive wheel binders, heat resistant bricks, calcium carbide production, carbon electrodes, welding rods, and cement manufacture. Some of the specialty fluoride salts currently manufactured are given in Table X.

-83- Figure XXI. Historical Trend Projection of Fluorine Use in the Ceramics Industry

% b. 20. a I c 00 e U o a •a n§ 3

1980 1990 2000 Year Table X. Partial List of Inorganic Chemicals Containing Fluorine

Fluoboric Acid Fluosulfonic Acid Metal Fluosulfonates Potassium Fluoride Sodium Fluoride Interhalogens Antimony Trifluoride Antimony Pentafluoride Barium fluoride Bismuth Trifluoride Cadmium Fluoride Chromium Fluoride C.upric Fluoride Magnesium Fluoride Mercuric Fluoride Manganese Trifluoride Molybdenum Hexafluoride Nickelous Fluoride Selenium Hexafluoride Silver Difluoride Stannous Fluoride Strontium Fluoride Titanium Tetrafluoride Tellurium Hexafluoride Tungsten Hexafluoride Zirconium Tetrafluoride Zinc Fluoride Sodium Monofluorophosphate Sodium Bifluoride Potassium Bifluoride Boron Trifluoride Sodium Fluoborate Ammonium Fluoride

-85- G. Future Trends of Fluorine Supply and Demand 1. Demand The data presented in Tables XI and XII are from the Bureau of Mines studies. Table XI shows high, low, arid probable demands for fluorine in the U. S. for the year 2000 according to end use. Table XII presents the totals from Table XI as well as totals from similar end-use com• pilations for the year 1985 and for the world in both i985 and 2000. Because tables similar to Table XI were also constructed for each intervening year, the cumulative totals could be obtained, and these are also presented in Table XII. Probable U. S. consumption of fluorine in 2000 is 2.8 times current consumption while world consumption will increase 3.1 fold. Figure XXII shows the 1975 projections of the Bureau of Mines for fluorine demand to 2000. The 1974 and 1975 demand figures were not used in the forecast. We assume the forecast range might have dropped somewhat if made after these figures were available. We also note that the projection was made prior to the most recent proposals for reducing use of chloro- fluorocarbons although the proposed ban was considered. We note that this projection for the U.S. demand in 2000 (Range 1,570-2,850; probable 1,940 tons fluorine) is consider• able less than the 1970 projection (Range 2,067-2,733; median 2,400)<. This almost certainly reflects environmental considerations and clearly shows that great changes can come in these projections due to newly evolving factors.

2. Supply Taking most of the factors of projected demand into account as shown in Tables XI and XII, the U. S. Bureau of Mines has estimated that the world fluorspar reserves are sufficient to satisfy world needs for the next 20 years. This estimate, however, was made before the fluorocarbon- ozone controversy was examined and so reserves may be sufficient for somewhat longer than this.

-86- Table XI. - United States projections and forecasts for fluorine by end use, 1973 and 2000 (Thousand short tons)

2 0 0 0 United States Contingency Forecasts End Use 1973 Forecast Forecast range base Low High Pr obable Chemicals -- 257 780 650 950 750 Iron and steel production (Flux)- 333 950 600 1,150 700 Nonferrous metal, production 153 440 300 605 400 I Ceramics and glass — 9 -4 -10 5 0 00 Iron and steel foundries 19 50 20 70 40 I Other 9 30 0 60 40 ' Total 780 1,560 2,840 1,930 Table XII Summary of forecasts of U.S. and rest of world fluorine demand, 1974-2000 (Thousand short tons fluorine content)

Probable average annual growth rate Forecast range Probable 1974-2000 1974 Low High 1985 2000 (Percent) United States: Total 689 1,560 2,800 1,560 1,930 4.0 Cumulative— 39,000 46,000 9,700 31,800 Rest of World: Total 1,644 3,000 7,500 2,720 5,420 4.7 I Cumulative— 80,000 112,000 24,070 84,260 00 World: 00 I Total 2,333 4,500 10,300 4,280 7,350 4.5 Cumulative— 11?,000 158,000 33,770 116,060 5000. High

2000.' v C Low 0) 4J c o o V c 1000 900 o 800 • 3 rH 700 . h 600 - •M H O 500 ■ •u o 400 •no c a n 3 300 I

200.

—r~ —I— —r- 1 70 80 90 I960 2000 Year

Figure XXII. Fluorine Demand Projection

-89- 4 In addition (refer to Table XIII), the total U. S. resources of phosphate rock (7 billion tons) contain 245 million tons of fluorine. At current U. S. consumption rates of phosphate, 46 million tons/yr., this fluorine will be mined out in 152 years. At this extraction rate, about 1.6 million tons of fluorine, or about 2.4 times current U. S. consumption rate (~675,000 tons/year) of fluorine, is mined each year. The current recovery of fluorine from this source is only about 46,000 tons of fluorine, or 2.9% of the total amount possible. The practical potential recov• ery capacity today, using today's processes, is estimated by the Bureau of Mines to be 295,000 tons of fluorine per year, or 18.3% of theory, or about 44% of current annual fluorine consumption. Thus, 249,000 tons of fluorine per year in addition to current production can be obtained from the phosphate source without technological modification or improvement. By the year 2000, again without technological changes, the Bureau of Mines estimates 500,000 to 800,000 tons/year of fluorine can be available from the phosphate industry. This would represent ~40% of probable total U. S. fluorine demand in 2000. We must emphasize that all the analyses of supply and demand of fluorine presented thus far assume a constant relative price for fluorine. However, the supply/demand picture can be modified significantly by price changes. For example, about 25 years ago, during the Korean war, there was a shortage of fluorospar: "Because the government was trying to establish a stockpile of this strategic mineral, a ceiling price of $60.00 per ton for acid grade concentrates was established at a time when the selling price had been about $50.00 per ton.

As soon as this ceiling price was established, under the price control laws in effect at that time, the going price immediately went to this figure of $60.00, and greatly stimulated the search and production of fluorspar all over

-90- Table XIII. Fluorine Supply Potential From The Phosphate Industry

Total U0 S. resources of PO. rock 7 Billion Tons Current U. S. PO. rock consumption rate 46 Million Tons/yr. Fluorine content of U. S. PO. rock 245 Million Tons Amount of fluorine in PO. rock extracted 1.6 Million Tons/yr. 4 Time until depletion of fluorine at this 152 Years extraction rate Ratio of fluorine from PO. extracted/yr. to annual U. S. fluorine consumption 2.4 Current fluorine extraction rate from PO. 46,000 Tons/yr, Percentage fluorine recovery of fluorine extracted 2.9% Practical fluorine recovery rate, today's technology 295,000 Tons/yr. Percentage practical fluorine recovery to total fluorine extracted 18.3% Percentage practical fluorine recovery of current U. S. consumption 44% Additional amount of fluorine practical to recover today 249,000 Tons/yr. Estimate of practical fluorine recovery- rate by 2000 800,000 Tons/yr.

-91- the world. The $60.00 price actually was established in the last quarter of 1951, and began weakening the last quarter of 1953, when a price of $57.50 per short ton was established. During the following year substantial amounts of new production came from Mexico, which exerted pressure on the price so that by the end of 1954 the price had dropped to $47.50 per ton." 232 The new reserves discovered as a result of the price increase have modified the supply situation greatly for the last 25 years. Assuming sufficient demand, any additional price increase is expected, similarly, to increase reserves, both through new discoveries and utility of resources of lower concentration.

-92- H. Supply - Demand of Metals The abundance of the metals and their origin are crucial to the availability of large quantities of metal fluorides. There are many estimates of the relative abundance of metals in the earth's crust. These estimates, which come from a variety of sources, differ somewhat in order of ranking, depending on the definition of the earth's crust and certain other assumptions made in arriving at these estimates. However, most estimates agree that the following metals rank among1 the 18 most abundant: Silicon Strontium Aluminum Barium Iron Zinc Calcium Rubidium Sodium Vanadium Potassium Mixed Rare Earths Magnesium Chromium Titanium Nickel Manganese Copper Therefore, these elements are likely candidates as components of metal fluorides for heat storage. Because the relative accessibility and other factors are also important, certain less abundant elements may also be of interest, such as: Boron Cobalt Zirconium Tin Lithium All other elements, except for the abundant non-metallic elements oxygen, carbon, nitrogen, phosphorous, hydrogen, chlorine, and sulfur can be eliminated from consideration on the basis of abundance in the earth's crust. On the other

-93- hand, the reserves and resources of these elements are more significant than the general natural abundance. The best estimates of reserves and resources of selected elements have been assembled by the Department of Interior and are reproduced in Tables XIV and XV. Inspection of these tables reveals that the most abundant elements with proven reserves, in decreasing world order of abundance, are: Silicon Iron Aluminum Calcium Sodium Potassium Magnesium Copper Lead Zinc Barium Titanium Manganese Nickel One good indication of availability of a metal is its cost in the chemical composition required. Consequently, the starting materials to produce the metal fluorides, the costs of these starting materials, and the ultimate mineral source of the metals used to prepare these starting materials have been determined and are presented in Table XVI. Examina• tion of this table indicates that the following metals are most desirable on a cost basis (presented in increasing order of cost, weighted for atom percent content of starting material):

-94- Table XIV. Abundance. Mass. Reserves, and Resources of Some Metals in the Earth's Crust and in the United States Crust [Abundance in grams/metric ton (g/mt); mass and reserves in metric tons (mt). Calculations = mass (metric tons) x abundance (decimalized) = total content of element]

United States World

Recoverable Ratio e Ratio Total earth s crust Oceanic crust Continental crust Reserve * resource of Reserve' resource of potential ' potential potential 1 potential Grade' to to reserve Element Gold- Vino• Lee and aebmidt • gradov ' Yao* MtXlO u •G/mt MtXlO " •G/mt MtXlO " MtXlO • MtXlO' MtXlO' MtXlO' (g/mt) (g/mt)

Antimony 1 0.5 0 62 14.9 0.91 8.1 0.45 6.8 0.10 1.1 11 8.6 19 6 Unknown. Beryllium .. 6 8.8 1.8 81.2 .88 7.4 1.6 23.8 .078 8.7 60 .016 64 4.000 Bismuth .2 .009 .0048 .1 .0069 .069 .0029 .041 .018 .007 .6 .081 .12 1.6 Cobalt 40 18 26. 600 87 830 18 270 .026 44 1,760 2.14 763 860 Copper 70 47 68 1.510 86 760 60 760 77.8 122 1.6 200 2.120 10 0.86 percent. Cold .001 .0048 .0036 .084 .0036 .032 .0035 .062 .002 .0088 4.1 .011 .15 14 1$ 18 12 290 10 90 13 200 81.8 81.8 I .54 550 1.000 8 percent Lithium 66 82 21 600 20 180 22 320 4.7 64 12 .78 933 1.200 I Mercury .6 .088 .089 2.1 .11 .9 .08 1.2 .013-028 .20 16-6.8 .11 8.4 80 10 Molybdenum 2.8 1.1 1.3 31.2 1.6 14.6 1.1 16.6 2.83 2.7 1 2 46.6 23 Unknown. Ul Nickel too 68 89 2.130 140 1,200 61 920 .18 149 830 68 2.690 88 1.6 percent. Niobium 20 21 19 460 18 160 20 300 Unknown 49 Unknown Unknown 848 Unknown I Platinum -_ .005 .046 1.1 .075 .67 .028 .48 .00012 .07 660 .009 1.2 133 Selenium .09 .05 .075 1.8 .1 .89 .069 .91 .026 .14 6 .696 2.6 36 Silver .02 .07 .075 1.8 .091 .82 .0G5 98 .06 .16 8.2 .16 2.75 18 Tantalum 2.1 2.6 1.8 88.4 .43 8.8 2.3 34.7 .0015 6.6 4.000 .274 97 364 Tellurium .0018 .001 .00056 .018 .00088 .0078 .00036 .005 .0077 .0009 .11 .064 .016 .8 Thorium _. 11.5 18 5.8 140 4.2 87 6.8 .100 .64 16.7 81 1 288 2G8 Unknown. Tin 40 2.6 1.7 40.8 1.9 16.8 1.6 24 8.9 •t 6.8 68 12 0.6 percent. Tungsten _. 1 1.8 1.1 26.4 .94 8.8 1.2 18.1 .079 2.9 87 1.2 61 42 Uranium 4 2.6 1.7 40.8 1 7.8 2.2 83 .27 6.4 20 .88 88 112 Zinc 80 88 94 2.250 120 1.030 81 1.220 81.6 198 6.8 81 3.400 42 4 percent Ratio of Ratio of G/mt G/mt G/mt MtXlO" G/mt MtXlO" G/mt MtXlO" MtXlO' MtXlO' potential MtXlO* MtX 10* potential to to reserve reserve

Aluminum ...... 81,800 80.600 83.000 1.990 84.000 747 83,000 1.242 8.1 203,000 24,000 1,160 8.519 8.000 Barium . .... 430 650 390 9.4 370 3.8 400 6.1 80.6 980 82 79.4 17 223 Chromium . 200 83 110 2.6 160 1.4 77 1.2 1.8 189 387 696 8.26 47 Fluorine 800 660 460 10.8 420 3.74 470 7.1 4.9 1.151 236 36 20 600 Iron 60,000 46,500 58.009 1.392 75,000 667 48.000 725 1,800 118,000 65 87.000 2,036 23 Manganese —. 1,000 1,100 1.800 312 1,800 16 1,000 15.2 1 2,450 2.460 630 42 67 Phosphorus 1,200 930 1.200 28.8 1,400 12.6 1.200 16.8 931 2.840 8 15,000 61 34 Titanium 4.400 4.600 6,400 163.6 8,100 72.1 6,300 81 6 26 18.000 516 117 225 2.000 Vanadium _. . 160 91 140 3.36 170 1.51 120 1.85 .116 294 2.660 10 6.! 600

• U.S. Bureau Mines (1870); 1 short ton >=0.91 mt 'Recoverable resource potential = 2.45 A X 10 • (abundance A expressed in g/mt). "U.S. Bureau Minra (1970): 1 short ton =0.91 mt: does not include United States reserve. > Recoverable resource potential .=2.46 A X17.3X10 • (abundance A expressed in g/mt; land area of world is 17.8 times United States land aram). •U.S Bureau Mines (1970); data on world basis. • Coldachmidt (1964, p. 74-76). 'Vinogradov (1962, p. 618-660). • Lee and Yao (1970, p. 778-786). All calculations are based on this work. » Very high. Table XV. Abundance of Some Elements in the Earth's Crust Earth's Crust Earth's Crust Abundance Concentration Element (%) (ppm) Zirconium 170 Silicon 25.67 311,000 Boron 9 Strontium 0.02 300 Sodium 2.63 31,900 Potassium 2.40 29,500 Magnesium 1.93 133,000 Calcium 3.39 25,700

-96- Sodium Aluminum Calcium Magnesium Boron Barium Iron Silicon Potassium Strontium Examination of similar starting material cost data was sufficient to eliminate the following metals from further consideration. Scandium Gallium Germanium Selenium Rubidium Yttrium Niobium Technetium Ruthenium Rhenium Silver Cadmium Indium Antimony Tellurium Cesium All elements above atomic number 56 except lead. Nevertheless, some metal fluorides of some of these metals will be discussed in the Chemistry Evaluation section for the contribution of their data toward understanding the missing data of the cheaper fluorides.

-97- The rates at which reserves are being depleted can be inferred by inspection of Table XVI in conjunction with Tables XIV and XV. Table XVI gives the production ton• nages for the more common metals in 1974. These data are taken from more detailed analyses of the supply and demand for these metals prepared by the Bureau of Mines. Summaries of some of these supply-demand analyses are reproduced in Appendix I. Clearly, the metals in highest production are (in decreasing order): Iron Calcium Sodium Potassium Aluminum Copper Zinc Titanium Magnesium Based on detailed considerations of projected consump• tion rates, the Department of Interior has evaluated the ability of the U. S. reserves to meet demands to the year 2000. Certain metals are in such high abundance in relation to demand that they were not analyzed: Calcium Sodium Potassium Silicon Magnesium Projections that were made are reproduced in Table XVII. The metals judged to be in highest abundance in the U. S. in relation to U. S. demands are:

-98- Table XVI. Production of Minerals (Metal Content) in 1974 Production (Thousand Short Ton) Element U. S. Rest of World Total Al 458 17,942 18,400 Sb 0.661 77.090 77.751 As NA 50 50+ Ba 619 2,063 2,682 Be NA1 0.159 NA B 193 135 328 Cd 1.9 16.9 18.8 Cs NA 0.03 0.03 Cr 0 2,536 2,536 Co NA 0.034 0.034 Cu 1,597 6,508 8,105 Fe 57,600 508,400 566,000 Pb 644 3,181 3,845 Ca (From CaO) 15,476 71,496 86,973 Li NA 2.475 NA Mg 950+ 4,576 6,526+ Mn 35 10,185 10,220 Mo 0.051 0.044 0.095 Ni 14.1 809.1 823.2 K 2,118 19,518 21,636 Rate Earths 22.482 9.017 31.499 Na (From NaCl) 18,290 48,269 66,560

Na (From Na2C03) 3,478 7,525 11,003 Sr 0 49 49 Sn NA 227.6 NA Ti 257 1,331 1,588 V 5.368 23.329 28.697 Zn 500 5,884 6,384 Zr NA 266.65 NA

1. NA = not available -99- Table XVII. Potential U. S. Resources of Some Important Mineral Commodities, in Relation to Minimum Anticipated Cumulative Demand to Year 2000 A.D,

Identl- Minimum anticipated Hed Hypothetical Commodity cumulative demand, re- resources 1968-2000 ' sources Aluminum 290,000,000 ST II Not estimated. Asbestos 32,700,000 ST V VI Barite — 25,300,000 ST II II Chromium 20,100,000 ST VI VI Clay 2,813,500,000 ST III II Copper 96,400,000 ST III III Fluorine „ 37,600,000 ST V V Gold 372,000,000 Tr oz III Not estimated. Gypsum .__ 719,800,000 ST I I Iron 3,280,000,000 ST II I Lead 37,000,000 ST III - IV Manganese 47,000,000 ST III Not estimated. Mercury 2,600,000 flasks V Not estimated. Mica, scrap 6,000,000 ST II I Molybdenum 3,100,000,000 lbs I I Nickel 16,200,000,000 lbs III Not estimated. Phosphate ... 190,000,000 ST II I Sand and gravel . 56,800,000,000 ST III Not estimated. Silver 3,700,000,000 Tr oz III . Ill , Sulfur 473,000,000 LT I I Thorium 27,500 ST' II Not estimated. Titanium (TiO.) . 38,000,000 ST II II Tungsten 1,100,000,000 lbs IV IV Uranium 1,190,000 ST II HI Vanadium 420,000 ST II Not estimated. Zinc 57,000,000 ST II II

1 As estimated by U.S. Bureau of Mines, 1970. -' For thorium, maximum anticipated cumulative demand 1968-2000. which assumes commercial development of economically attractive thorium reactors by 1980.

ST=short tons. lb=pounds. LT=?long tons. Tr or—troy ounces. Identified resources: Includes reserves, and materials other than re• serves that are reasonably well known as to location, extent, and grade. that may be exploitable in the future under more favorable economic conditions or with improvements in technology. Hypothetical resources: Undiscovered but geo'ofrtcally predictable deposits of materials similar to present identified resources. I. Domestic resources (of the category shown) are greater than 10 times the minimum anticipated cumulative demand 1968-2000. II. Domestic resources are 2 to 10 times the MACD. HI. Domestic resources are approximately 1o percent to 2 times the MACD. IV. Domestic resources are approximately 36-76 percent the MACD. V. Domestic resources are approximately 10-36 percent the MACD. VI. Domestic resources are less than 10 percent of the MACD.

-100- Aluminum Barium Iron Molybdenum Thorium Titanium Uranium Vanadium Zinc The U. S. Council on International Economic Policy has analyzed these and other data and has ranked the lifetimes of the reserves. Its conclusions are shown in Table XVIII. It is probably reasonable to consider any of these metals with proven reserves of 15-25 years or more, especially con• sidering the fact that the metals used in heat storage applications will not be lost for future use in other appli• cations. The Council warns that scarcity forecasts under• estimate the real potential because they are based only on proven reserves. These reserves are constantly increasing because of price changes, the discovery of new, minable deposits, and the development of technology allowing the exploitation of previously uneconomic deposits. For example, see Figure XXIIa, which shows the increase in world proven reserves that occurred during the years 1950-1970.

Data giving the extent to which selected raw materials are imported are given in FigureXXIII. The higher the metal is located on this figure, the greater percentage of it is imported; therefore, those materials whose supplies are most susceptible to changes in the international situation occur at the upper part of the figure.

-101- Table XVIII. Supply Forecasts for Selected Minerals Based on Proven World Reserves

More Than 100 Years: Columbium Potash Phosphorus Magnesium

51-100 Years: Iron Ore Chromite Nickel Van ad i vim Cobalt Asbestos Molybdenum

26-50 Years: Manganese Bauxite Platinum Titanium Antimony Sulfur

15-25 Years: Copper Lead , Tin Zinc Tungsten Barite

10-15 Years: Mercury Silver

-102- Figure XXIIa. Change in World Proved Reserves 1950-70

PERCENT 500 600 1,000 1.S00A 2,000 2,500 ~TVT" 1 -.n^ft-^'JTf'M U-'^7KT*nyH&r ^r.-Tw^^.a^^wr^^ *, POTASH r fC-J. " .J.J- '■-- ...-y.l'M. -.^■,, ■•-'-. 1 IRON ORE i

CHROMITE

PETROLEUM

BAUXITE

COPPER

LEAD

ZINC

MANGANESE

TIN

TUNGSTEN

-103- Figure XXIII. 1975 Imports Percentage of Minerals and Metals U. S. Consumption

MINERAL PERCENTAGEIMPORTED MAJOR FOREIGN SOURCES 0". IV. 60". 75% loox _l I 1 _) COIUMBIUM 100 WREBMBBEBBBSffl&SMKEBUUfi BHAZIL. THAILAND. NIGERIA MICA lihd-ll 100 WSSSESS^^l&SStSSSSi^SSfe^SKB INDIA. BRAZIL. MALAGASY STRONTIUM ioo tiz':'^esd£Ti^.- ssa gaggsf^an MEXICO.U K .SPAIN MANGANESE 99 EKKSSSSeMS ^aSKaf-*^saigjygj|)«fflgg BRAZIL, GABON. AUSTRALIA, SOUTH AFRICA COBALT 98 WSn^ff^W^^^f^^S^^^S^lWD ZAIRE. BELGIUM LUXEMBOURG. FINLAND NORWAY. CANADA TANTALUM 95 ES^SSft-^^i^aiiTiStSH'lC^aD THAILAND. CANADA AUSTRALIA. BRAZIL CHROMIUM 91 Ei£SE3ES£S£ l2'£^,£lil2'l,F?~&5'lXW3E3 SOUTH AFRICA. u s s R . TURKEY. RHODESIA ASBESTOS 86 EaEBSG3ESB^IJ.^®;3E CANAOA. SOUTH AFRICA : ALUMINUM (or..s 8, metal) 85 »S^™Z.7i-I-l^X7.'fX^TJ'L" £-^.S^a___J JAMAICA, SURINAM. AUSTRALIA. DOMINICAN REPUBLIC MUORINE 8? !2^>jSS^&iC?;?fii3S3.CSSESIZZZD Mexico, SPAIN. ITALY HISMUTH 80 BggS&ffl&£B52£68M3%&BBBK~ZZZD PERU.JAPAN.MEXICO.UK PLATINUM GROUP METALS v 80 t*Zli..i.i.i,iJ£,. *>' Kiasa: SOUTH AFRICA. U K . U S S R TIN MALAYSIA. THAILAND. BOLIVIA Ml RCURY rase CANAOA. ALGERIA. MEXICO. SPAIN NIOEL /i B22S58225H CANAOA. NORWAY /INC. 64 essoestass CANAOA. MEXICO. AUSTRALIA. HONDURAS. PERU TEL I URIUM so BP^SBSSI sassac: PERU.CANAOA SELENIUM 58 ESSE^JS:: :':.. :rssc CANAOA. JAPAN. MEXICO ANTIMONY 56 $££tS&^J5&LLl* SOUTH AFRICA. P R CHINA. BOl IVI A. MEXICO TUNGSTEN CANADA. BOLIVIA. THAILAND. PERU CADMIUM 50 t^sssx^ss^mac MEXICO. CANADA. AUSTRALIA. BELGIUM LUXEMBOURG POTASSIUM 49 egar^^sssaz: CANAQA GOLD 45 ESKiSissfflaazz: CANADA SWITZERLAND U K . FRANCE GYPSUM CANADA. ME XICO. JAMAICA VANADIUM 36 w@&eimsBC SOUTH AFHIC A. CHILE.USSR BARIUM 35 E8^&j£^fa2SS^Z IRELAND. PERU. MEXICO PETROLEUM I NJI Gas Mi I 36 KgMaglBBB8!W: CANADA. VENEZUELA NIGERIA. SAUDI ARABIA SILVER 30 mmftsmmr CANADA. MEXICO. PERU IRON ?9t^E2K CANADA. VENEZUELA, JAPAN. COMMON MARKET (EECI TITANIUM lilnvrtitel ?H CANADA. AUSTRALIA SALT 6B0C CANADA. MEXICO. BAHAMAS. CHILE PUMICE 5 mz GREECE ITAl Y CEMENT CANADA. BAHAMAS NOHWAY. U K LEAD 4BT CANADA. PERU. AUSTRALIA. MEXICO NATURAl GAS 4ia: CANADA MAGNESIUM Im.'iin.fl.llicl 3D! GRtFCE. IRELAND. JAPAN r~ 1 I I 25". 50'. 75". NET IMPORT RELIANCE ••

BUREAU OF MINES. US DEPARTMENT OF TME INTERIOR l.inooil ..«pori dan Irom Bureau ol lh< Drmusl

-104- I. Supply - Demand of Metal Fluorides The supply-demand of calcium fluoride was discussed earlier, because it is the principal fluorine bearing mineral of commerce. Supply•of- other metal fluorides also depends on production factors. Aluminum fluoride and cryolyte are made on many multi-ton bases, but their markets are captive. Currently, none of the other metal fluorides are made on a large scale. Sodium fluoride is produced in greater quantity than any other metal fluoride. Annual U. S. production of all inorganic metal fluorides requires about 14,000 tons of fluorine. Some of the companies that offer metal fluorides, their addresses, and phone numbers are given in Appendix II. There is a great deal of experience in the manufacture of a broad variety of metal fluorides on a small scale. For large scale supply of metal fluorides, then, sufficient lead time and sufficient market incentive must be provided to the chemical manufacturers. New plant capacity would have to be installed to meet large scale requirements.

'■> If the market incentive and lead time are provided, we estimate the potential for metal fluoride production at current raw materials' prices and without competing with other fluorine . consuming industries to be over 600,000 tons/year. This estimate is based on current availability of fluorine and assumes the metal and fluorine weights to be equivalent. Therefore:

249,000 Tons F/yr. available from P04 source 75,000 Tons F/yr. available from 10% increase in U. S. and Mexico Fluorspar production 324,000 Tons F/yr. available 324,000 Tons M/yr. assumption 648,000 Tons of MF/yr. Again, it must be emphasized that a slight increase in the price of fluorspar would rapidly make additional amounts of fluorine available.

-105- J. Supply ­ Requirements of Metal Fluorides for Heat Storage The quantities of metal fluorides required for most heat storage applications have not been determined, so the relation­ ship between supply and demand for these applications cannot be precisely evaluated. It is possible, however, to predict this relationship within an order of magnitude. 217 A recent conceptual engineering study stated that about 13,000 tons of'fluoride salts would be required for a 500 mw thermal energy storage system. If 50 of these systems were constructed each year, then 650,000 tons of metal fluoride salts would be required. This is approximately the amount of material that we predict can be available under current technology and market conditions without competition for resources from other applications. If electrical resistance heaters were constructed for residential peak shaving purposes, then similarly adequate supplies would be available. Assuming a storage requirement for this purpose of 150,000 Btu/heater and deep discharge between 850°C and 150°C, a mixture of 75NaF/25MgF2 at $0.08/lb* might be used. This mixture has a heat of fusion of 155 cal/g and a sensible heat between these temperatures of 275 cal/g for a total heat storage capacity of 430 cal/g or 1264 cal/cc. Calculation shows that 150,000 Btu can be provided by about 3 1.1 ft (or 194 lbs) of this mixture. If, for example, 5 million units containing this amount of material were manufactured each year, the demand for metal fluorides would be 494,000 tons, a figure well within predicted current availability. Because any heat storage technology will take some years to develop, it is important to note again that future availa­ bility of fluorine from the phosphate industry is predicted to be much higher than it is now and this fluorine can be expected to be available for this application. It is inter­ esting to note also that if a commitment were made now to

♦Production cost. ­106­ guarantee a market for metal fluorides, a considerable portion of the 249,000 tons/year of recoverable fluorine that is now vented as an air pollutant by the phosphate industry could be recovered and stored for later use. Currently there is no market for this material, so it is thrown away.

-107- V. METAL FLUORIDE COSTS Metal fluoride costs are basically functions of the costs of fluorine, selected metals and production. Naturally the costs of these three variables are functions of the forms in which the fluorine and metals are available, the production volume, and other factors including competition for resources and government regulations. A. Current Costs Table XIX shows current prices and estimated production costs of selected fluorine compounds. Current prices, with the few exceptions of those for HF, CaF2, H_SiFfi, AlF.,, and Na-.AlF,, are based on low production volumes. The production cost estimates are based on the reactions that are discussed in this report and higher production volumes. The estimates were made with the assistance of a computer program based on 286 the work of Zernik and Buchanan. In this program, the following factors are used to give exploratory cost estimates: raw material costs, production level, process complexity, materials of construction, operating conditions, labor, con• struction cost indexes, general service, supervision, deprecia• tion, overhead, technical service, inventory, and accounts receivable. Within process complexity, all the reaction steps, reagent metering, product separation, purification, process control, recycling, and pollution control are consi• dered. For the purpose of this analysis, we used 10% per year depreciation on construction cost and 25% overhead of the total labor, other direct costs and depreciation. Reaction yields of 98% were assumed. Reactors and other equipment were assumed to be constructed of stainless steel, and a liming procedure for pollution control was included. The estimates are presented at three production levels. For each production level, the estimates were made four times to show the effects of various fluorine sources on metal fluoride costs. In one instance, hydrofluoric acid, obtained at market price, was chosen as the fluorine source. In another

-108- Table XIX. Prices and Estimated Prodiactio n Costs of Flvlorid e Compounds ( 99* Puritv) Hiqh Volume Current Production Rate (Tons/year) Price ' 10.000 50.000 100.000 10.000 50,000 100,000 10,000 50,000 100,000 10,000 50,000 100.000 Compound (?/">) Production Costsl($/lb) Production Costs^($/lb) Production Costs3($/lb) Product ion Costs*($/lb)

NaF 0.331 0.29 0.26 0.26 0.22 0.20 0.20 0.18 0.15 0.15 0.09 0.06 0.05 KF 0.655 0.36 0.34 0.33 0.32 0.29 0.28 0.29 0.26 0.26 0.22 0.19 0.19 MgF2 0.39-0.77 0.38 0.35 0.34 0.30 0.27 0.26 0.24 0.21 0.21 0.11 0.08 0.08 CaF2 0.053 -—- --— —-- —— -—- —-- - BaF2 0.58 0.28 0.25 0.25 0.25 0.22 0.22 0.23 0.20 0.20 0.18 0.15 0.15 TiF4 35.00 0.60 0.57 0.57 0.51 0.48 0.47 0.46 0.43 0.42 0.33 0.30 0.30 MnF2 35.00 0.62 0.59 0.58 0.53 0.50 0.49 FeF3 88.00 ZnF2 35.00 0.54 0.51 0.51 0.49 0.46 0.45 0.45 0.42 0.42 0.37 0.34 0.34 A1F3 0.175 0.41 0.38 0.38 0.31 0.29 0.28 0.26 0.23 0.22 0.11 0.08 0.08 1 SrF2 22.70 0.41 0.38 0.38 0.37 0.34 0.33 0.34 0.31 0.31 0.28 0.25 0.24 y-> PbF2 13.62 0.49 0.46 0.45 0.47 0.44 0.43 o 1.35 1.32 VO LiF 2.42 1.51 1.48 1.47 1.41 1.38 1.37 1.32 1.19 1.16 1.16 I CuF2 54.50 1.34 1.31 1.31 1.29 1.26 1.26 1.08 1.05 1.04 1.00 0.97 0.96 NiF2 91.00 1.81 1.78 1.78 1.76 1.73 1.72 1.72 1.69 1.68 1.63 1.61 1.60 ZrF4 27.25 1.95 1.92 1.91 1.88 1.85 1.85 1.84 1.81 1.80 1.74 1.71 1.71 CrF3 0.81 2.69 2.66 2.66 2.55 2.52 2.51 2.35 2.33 2.32 2.24 2.21 2.21 SnF2 5.60 6.87 6.84 6.83 6.81 6.79 6.78 Na3AlF6 0.265 H2SiF6 0.163 Na2P03F 1.20 HF 0.41 <0.28 -

1. Based on HF, market price = $0.41/lb, as the fluorine source. 2. Based on HF, production cost « $0.28/lb, as the fluorine source. 3. Based on H2SiFg, market price = $0,163, as the fluorine source. 4. Based on H2SiFg, cost =» free, as the fluorine source. case, the cost of hydrofluoric acid was lowered to reflect the ability of a hydrofluoric acid producer to undercut the market price if he were to manufacture the metal fluoride himself. In the third case, fluosilicic acid, obtained at market price, was chosen as the fluorine source. In the fourth case, the cost of the fluosilicic acid was assumed to be negligible, reflecting its cost to a fertilizer manufacturer, who, for lack of market, must usually pay to dispose of this pollutant. The starting material costs were taken from the Chemical Marketing Reporter, September, 1976, and are shown in Table XX. Note that the estimated production costs are significantly lower than current market prices, indicating economies of scale. However, only slight additional economies of scale among the production levels estimated are apparent. In all cases, fluosilicic acid appears to be the reagent of choice on a cost basis. On the other hand, hydrofluoric acid has been more widely employed because of availability. As a result, the procedures using hydrofluoric acid are more highly developed. For easier comparison of current, low volume prices with the selling prices of these same metal fluorides if produced on a large scale, the prices shown in Table XXI were calcu• lated based on a 40% rate of return and H„SiF^ as the starting source of fluorine. These prices were then used to calculate the prices of the eutectic mixtures presented in Tables XXXV and XXXVI. The least expensive metal fluoride compounds are those containing Ca, Na, Mg, Al, Si, Ba, K, and Sr. These compounds and most of their mixtures have melting points above 450°C. If fluoride materials are desired that have lower melting points, then mixtures that contain the expensive compounds, LiF, SnF„, and ZrF^, are required.

-110- TABLE XX. PRICES OF STARTING MATERIALS FOR METAL FLUORIDES Starting Current Price 1985 Price 2000 Price Material ($/lh)1 ($/lb)2 ($/lb)2

NaOH 0.0883 Na2C03 0.0238 0.0315 0.049 HF 0.41 (0.28) 0.465 0.54 KOH 0.1667 0.20 0.32 BeO 25.00 MgO 0.0875 0.0875 0.0875 Ti02 0.415 0.44 0.50 TiCl4 0.35 0.37 0.42 FeCl3 0.125 0.15 0.20 ZnO 0.395 0.52 0.71 Al203 0.091 0.099 0.115 Li2C03 0.7751 0.84 0.84 CUCO3 0.8625 0.95 1.10 CuO 1.18 1.03 1.16 Sn 4.34 5.00 8.00 SnO 5.453 6.11 9.11 BaC03 0.111 0.125 0.125 MnC03 0.30 0.30 0.30 SrC03 0.184 0.21 0.27 Pb 0.20 0.25 0.25 PbC03 0.355 0.385 0.385 NiO 2.00 2.09 2.25 Zr02 0.81-2.22 0.81-2.22 0.81-2.22 cr2°3 1.531 1.60 1.72 Ca5?2 0.053 0.058 0.0675 ZrCl4 0.50 0.50 0.50 CrF3 1.453 1.52 1.63 C0CO3 2.99 2.99 2.99 Mixed Rare Earths 2.00 2.20 2.50 Na2B407 0.125 0.125 0.125

1. September, 1976, Chemical Marketing Reporter figures. 2. 1976 Dollars. Estimates based on December, 1976 Chemical Marketing Reporter figures. 3. $0.10 premium estimate included for drying.

-Ill- TABLE XXI . ESTIMATED CURRENT PRICES OF METAL FLUORIDE COMPOUNDS

Metal Selling Price Selling Pr Fluoride ($/lb)1 ($/ft3)

CaF2 0.05 9.67 NaF 0.07 11.18

MgF2 0.11 20.58

A1F3 0.11 21.06

H2SiF6 0.163

BaF2 0.21 64.05

Na3AlF6 0.265 48.76 KF 0.27 41.76

SrF2 0.34 90.98

TiF4 0.42 73.30

ZnF2 0.48 146.70

CUF2 1.34 405.36 LiF 1.62 266.75

NiF2 2.24 646.87

ZrF4 2.39 676.77

CrF3 3.09 732.37

SnF0 9.49 2705.03

1. Based on Table XIX and 40% rate of return.

2. H9SiFA is sold as an aqueous solution.

-112- Although the standard marketing unit for chemical sales is $/lb, we have also presented the estimates of selling 3 prices in $/ft in Table XXI . Of course, these cost figures are not enough to directly compare materials and in fact, there is no universally acceptable way to compare costs of materials unless their potential application is precisely defined. For example, a tabulation of energy stored/dollar is misleading without a definition of the temperature interval over which the energy is stored and knowledge as to whether or not it is stored as sensible heat and/or heat of fusion. In addition, the total system cost relates to the equipment as well as the storage material. Thus, a material shown to have low energy/dollar cost may take more volume to handle, thus requiring more equipment than a higher priced material. The result may be that the material of lower energy/dollar may turn out to be more costly to use. This must be examined on an individual basis, and is one reason for the requirement of extensive tabulation of thermophysical and cost data for heat storage candidates. The influence of degree of purity on selling price is of special concern because the required level of purification for heat storage purposes is not now known. The purification steps included in the program that gave the production costs in Table XIX are considered sufficient to give 99% pure com• pounds. Additional purification, more rigorous drying, etc., \ if required, would cost more. For MgF2, we re-ran the pro- gram, adding one, two, and then three additional purification, procedures, each consisting of two steps. The resulting pro• duction costs were as follows:

99% MgF2 $0.0779/lb

99% MgF2 + 1 Purification Procedure 0.0813/lb

99% MgF2 + 2 Purification Procedure 0.0846/lb

99% MgF2 + 3 Purification Procedure 0.0880/lb Thus, the expected increase in production costs for an inexpen-

-113- sive metal fluoride can be as much as 13% if three additional purification procedures are required.

-114- B. Future Costs In order to project costs of metal fluorides to the years 1985 and 2000, we have for the most part used projections and assumptions made by the Bureau of Mines for the bases of costs of the starting materials. We then re-ran the computer program, using the same technology and labor factors. The results, Table XXia, are in 1976 dollars and do not reflect infla tion, improvements in technological efficiencies that might be expected, or changes in the cost of labor. For the pur• poses of this report, we have accepted all of the Bureau of Mines' assumptions about the future concerning geo-political stability, demographic trends, standards of living, produc• tivity, and all the other variables required for this type of analysis. The projected costs of the starting materials are summarized in Table XX and discussed below. Some of these data are extrapolated, from more than one Bureau of Mines report.

Sodium The starting material for sodium fluoride can be either sodium hydroxide or sodium carbonate. The prices of these two compounds can vary widely because the sodium hydroxide price is dependent upon such factors as the demand for co- product chlorine. The starting material of choice would be the lower cost one, which usually would be the carbonate. 198 In the 1970 edition of Mineral Facts and Problems prices of Na2C03 were projected to be constant in terms of constant dollars to the year 2000. In constant 1973 dollars the average annual cost per ton of soda ash from 1955-1975 has been $23.15-$43.76, according to the 1975 edition of Mineral Facts and Problems. This can be represented by $33.50 ± $10.50/ton and refers to the bulk price at the plant. The 243 1975 price of $35.85 per ton in constant 1973 dollars and the 1976 price of $47-49/ton282 (about $37 in constant 1973

-115- TABLE XXia. ESTIMATED FUTURE PRODUCTION COSTS AND PRICES OF METAL FLUORIDES

1985 2000 Metal Production Selling ^ Production Selling ~ Fluoride Costs ($/lb) Price ($/lb)J Costs ($/lb) Price ($/lb)J NaF 0.06 0.08 0.08 0.11 KF 0.22 0.31 0.34 0.48

MgF2 0.08 0.11 0.08 0.11

CaF2 0.06 0.08 0.07 0.10

BaF2 0.16 0.22 0.16 0.22

TiF4 0.31 0.43 0.35 0.49

A1F3 0.08 0.11 0.09 0.13

SrF2 0.27 0.38 0.35 0.49

PbF2 0.42 0.59 0.42 0.59 LiF 1.25 1.75 1.25 1.75

CuF2 •1.25 1.75 1.41 1.97

NiF2 1.67 2.34 1.80 2.52

CrF3 2.31 3.23 2.90 4.06

SnF0 7.60 10.64 11.32 15.85

1. Production from H0SiF., 100,000 lb/year level. 2. 1976 Dollars. 3. 40% rate of return assumed.

-116- dollars) are well within this range. A 1973 survey by the 243 Bureau of Mines reported that an average of 2,100 kilowatt- hours (7,200,000 btu) of energy is required to produce one ton of natural Na^CO-,. Since this represents a fairly energy intensive product, we feel we should include a 2% per year compounded increase in constant dollars to account for this. Using a $48/ton base in 1976 results in a projection of $63 ± $20/ton in 1985 and $98 ± $30/ton in 2000 FOB plant in constant 1976 dollars. Potassium The current price for 45% or 50% KOH is $0,075 per 282 pound but this is scheduled to increase to $0.08 per pound January 1, 1977. Because the process to produce KOH is highly energy intensive, a 3% compound price increase in constant dollars is projected. This gives a 50% KOH price of $0.10/lb in 1985 and $0.16/lb in 2000, both in constant 1976 dollars. Aluminum Although the price of aluminum metal is very energy sensitive, that of Al203, the starting material for AlF3 and

Na3AlFg, is not. Moreover, the natural abundance of aluminum oxides ensures that little price pressure from declining re• sources will occur. Therefore, only a 1% compounded price increase is projected. In constant 1976 dollars, the

Al20o*3H20 price is projected to increase from the current $0.059/lb282 to $0.065/lb in 1985 and $0.075/lb in 2000 in constant 1976 dollars. Lithium The current price of lithium carbonate is $0,825-0.84/ 282 198 lb. The Bureau of Mines projected an almost constant price for lithium to 2000 in constant dollars. We will use the $0.84/lb price for lithium carbonate to 2000 in constant 1976 dollars; however, development of new technology, such as the lithium-based battery, that would create greatly in-

-117- creased demand for lithium would be expected to cause an up• ward revision of this estimate. Magnesium Magnesium is abundant and readily available from sea- water. Its cost depends on the grade required. The chemical grade of magnesium oxide is currently $0.0875/lb and is expected to remain relatively unchanged to 2000 in constant 198 1976 dollars based on the 1970 Bureau of Mines projection to 2000. Calcium The Bureau of Mines no longer projects prices in Mineral Facts and Problems for calcium fluoride. Figure XXIV taken from the 1970 Edition of Mineral Facts and Problems gives a projection of fluorine prices in constant 1968 dollars. This shows an annual compounded increase of 1% per year in constant dollars. They stated, "As mines become deeper and discovery and recovery of fluorine becomes more difficult and expensive, prices will likely increase from about $100 per 198 ton of contained fluorine in 1968 to $133 in 2000." These figures are in constant 1968 dollars. Since 1968 there has been a sharp increase in price even in constant 1968 dollars as shown in Figure XXIV. This has continued into 1975 and 1976. 283 The Bureau of Mines reports the actual average annual price in 1975 to be $210/ton of contained fluorine. The December, 1976, published price for 97% acid grade fluorspar FOB Illinois is $106/ton which is $224/ton of contained fluorine. However, there was a downward trend from the Korean War peak to 1969. In constant 1973 dollars the average annual range from 1955- 1975 was $123.89 - $171.83. Although the recent increase has been steep, the chlorofluorocarbon-ozone controversy, pollu- . tion control in steel mills and the aluminum industry, possi• ble substitutes, and the Peso devaluation all suggest possible downward price pressures. The best projection to 1985 and 2000

-118- Figure XXIV. Time-Price Relationship for Fluorine

: ISO

2 000

-119- may still be the Bureau of Mines 1970 projection of a 1%/year compounded increase in constant dollars although the possibi­ lity of drops in the price in constant dollars should be con­ sidered. Using the 1976 price of $106 per ton of 97% CaF? a

1%/year compounded increase gives $116/ton 97% CaF2 in 1985 and $l35/ton 97% CaF2 in 2000 both in 1976 constant dollars. The fluorine value prices are $246/ton in 1985 and $286/ton in 2000 in constant 1976 dollars. Iron The current price of anhydrous ferric chloride is $.125/ pound. Because chlorine is energy intensive, the price of

FeCl3 may increase at the rate of 2% per year compounded in constant dollars. This gives a projected price of $.15/lb in 1985 and $.20/lb in 2000 in constant 1976 dollars. Lead 243 The price of lead is projected by the Bureau of Mines to show little increase in constant dollars. The average annual price of lead has ranged between $0.14­.223 in the period 1958­1976 in constant 1973 dollars. The December, 1976, 282 actual price is $.25/lb which is near the top of the range when corrected for 1973 constant dollars. We would project this $0.25/lb price for 1985 and 2000 in constant 1976 dollars. Reaction of lead metal with HF would be the route with the least'expensive raw materials. If this is impractical, the carbonate with a 1976 price of $.385 could easily be used. ■This price should be reasonably constant to 2000 in constant 1976 dollars. Manganese 198 243 Historically ' prices of manganese ores and products such as MnCO^, the preferred starting material for MnF2, have trended down in constant dollars. The Bureau of Mines pro­ 198 jected constant prices in constant dollars to 2000. The 282 current manganese carbonate price is $0.30/lb and is pro­ jected to be constant in constant 1976 dollars to 2000.: The 282 current metal price is $0. 3324 per lb which is about one­half

­120­ the cost of contained manganese in the carbonate. The oxide 282 price ($175/ton of 84% MnF_) is only one-fourth of the cost of the carbonate on a contained manganese basis. Zinc In 1970 the Bureau of Mines19 8 projected that the price of zinc would double in constant dollars from 1968 to 2000 because of lower grade deposits. This amounts to a compound increase of about 2.2% in constant dollars. The current zinc 282 oxide price is $.40-.45/lb, depending on grade. A 2.2% per year compounded increase would give a price of $.49-.55/lb in 1985 and $0.67-.76/lb in 2000 in constant 1976 dollars. Zirconium Current zirconium oxides are available at $.81/lb to 282 $2.22/lb. Zirconium tetrachloride was available at a much lower price from N. L. Industries but is no longer offered. We have been unable to locate a current volume scale supplier in a cursory search but believe it may still be produced for captive use in zirconium production. If production of ZrF. from ZrCl. appears promising, future studies might uncover a current source. If ZrCl. is not currently produced, pro• duction could be resumed if there is sufficient demand. For purposes of this estimate we will use a price for ZrCl. of $0.50/lb and the $0.81 estimate for ZrO^ constant in constant 1976 dollars to the year 2000 in full realization that these are little more than guesses because we are not certain if

ZrCl. will be available or what grade of Zr02 might be.re• quired. Nickel The nominal nickel price as reported by Metals Week (11/30/76) is $2.35 - 2.45/lb. The Chemical Marketing Repor- 282 282 ter reports $2.01/lb as the actual price. Nickel oxide 198 is listed at $2.00/lb. In 1970 the Bureau of Mines pro• jected a compounded annual increase to 2000 of less than 1/2% in constant dollars. Using the current oxide price of $2.00/lb and a compound annual increase of 1/2% a nickel oxide price -121- of $2.09/lb in 1985 and $2.25/lb in 2000 in constant 1976 dollars is projected. Beryllium Beryllium compounds are expensive as well as highly toxic. Beryllium oxide is priced at $26-28/lb 284 and the metal at $100 per pound. Because of this cost and the very restrictive exposure standard which has been recommended but not yet re• quired, we will not project future costs. Barium 282 The December, 1.976, price of barium carbonate is $250 per ton ($0.125/lb). We see no reason to change the 1970 Bureau of Mines19 8 projection of little if any change in barium prices in constant dollars to 2000. Therefore, in constant 1976 dollars $0.125/lb for barium carbonate in 1985 and 2000 is projected. Titanium 582 The December, 1976, prices of titanium chloride and titanium dioxide are $0.35/lb and $.41-.47/lb, respectively. The 1970 Bureau of Mines19 8 projection gave an increase in constant dollars of less than 3/4% per year compounded. Using 3/4% per year compounded $.37/lb in 1985 and $.42/lb in 2000 for TiCl4 and $.44-.50/lb in 1985 and $.50-.56/lb in 2000 for Ti02 in constant 1976 dollars are projected. Copper Over the period 1954-1974 the average annual copper price 243 ranged from $0.442-0.701/lb in constant 1973 dollars. Because the grade of ores being processed has declined as the richer ores have been exhausted, costs and prices have been increasing faster than inflation. A Bureau of Mines projection 198 in 1970 gave a compounded 1-1/4% increase per 282 year in constant dollars. With the 1976 price of $.65-.70/lb this gives a 1985 estimate of $.73-.78/lb and an estimate for 2000 of $.88-.94/lb both in constant~-l976 dollars. If we assume a constant premium in constant 1977 dollars of $.19/lb

-122- 282 282 for copper carbonate and $.27/lb for copper oxide, this gives copper carbonate estimates of $.92-.97/lb in 1985 and $1.07-1.13/lb in 2000 in constant 1976 dollars. It also gives copper oxide estimates of $1.00-1.05/lb in 1985 and $1.13-I.19/Ib in 2000 in constant 1976 dollars. Tin Tin is the only metal where an international agreement between producing and consuming nations attempts to stabilize the price by setting a price floor and ceiling. The Inter• national Tin Council attempts to maintain a floor by buffer- stock purchases and/or export controls and a ceiling by buffer- stock sales. The average annual price in constant 1973 dollars ranged from $1.46/lb to $2.48/lb from 1954-1973. However, in 1974 the U.S. price ranged from $2.80/lb to $4.73/lb. The 1975 range was $3.00-3.78/lb and the 1976 range about $3.06- 4.26/lb. The Bureau of Mines 198 in 1970 projected slightly less than a compound 1% per year increase in constant dollars to the year 2000. This is a highly volatile market even with the International Tin Council. Because of this volatility, the Southeast Asia source, and energy for transportation, a 3% per year compounded increase in price is used on a base 1976 price of $4.00/lb. This gives a price of $5.00/lb in 1985 and about $8.00/lb in 2000 in constant 1976 dollars. Tin dioxide and tin oxide prices will depend on the tin price plus a conversion premium. Hydrofluoric Acid The 1976 price of hydrogen fluoride is $.425. 282 This is $850 per ton. Calcium fluoride at $106 per ton (97%) contributes $213 of this cost assuming 100% yield. If use of chlorofluorocarbons, which are reported to consume 45 per• cent of the HF used in the U.S., are restricted, downward price pressure will result. However, even if this occurs, current U.S. HF capacity would probably all be again required by 1985 and this might have little effect on prices in 1985 and 2000. The other components of HF cost are sulfuric acid, the difficult reaction, corrosive products, and environ-

123- mental control. Therefore, a 1% per year compounded increase in constant dollars will be used. Based on $0.425/lb in 1976 this gives a projected price of $0.465/lb in 1985 and $.54/lb in 2000, both in constant 1976 dollars. Chromium Chromium fluoride is available commercially as the tetra- 282 hydrate at a December, 1976, price of $0.8l/lb. This corresponds to $1.35/lb for the dried product. If conditions can be developed to dehydrate this without hydrolysis, this will represent a commercially available product made by simple synthesis starting with an inexpensive oxide. If the anhydrous fluoride cannot be prepared by dehydration, a nonaqueous route such as reaction of anhydrous HF with the anhydrous chloride or possibly direct reaction of HF with the metal would be required. This would require considerably more expensive 198 raw materials. Two 1970 projections by the Bureau of Mines on chromium raw materials averaged about a 1/2% per year compounded increase to 2000 in constant dollars. For pro• jections we use the $1.35/lb price plus $.10/lb for drying as the base and a 1/2% compounded annual increase in constant dollars. This produces a projection of $1.52/lb in 1985 and $1.63/lb in 2000 in constant 1976 dollars. Cobalt 282 The December, 1976, price for cobalt carbonate is $2.99/lb and for cobalt metal is $4.40/lb. The Bureau of Mines19 8 in 1970 projected constant prices in constant dollars to 2000. We, therefore, project $2.99/lb for cobalt carbonate in 1985 and 2000 both in constant 1976 dollars. Strontium 282 The December, 1976, price for strontium carbonate is $.18/lb. The Bureau of Mines19 8 1970 projection gave a 1-3/4% compounded annual increase to 2000. Using the 1-3/4% figure we project the strontium carbonate price to be $0.21/lb in 1985 and $.27/lb in 2000 both in constant 1976 dollars.

-124- Mixed Rare Earths . ■ s • ■ Mixed rare earth fluorides are currently used for the production of Mischmetal and arc carbons. Price information on these fluorides is not readily available but we were ad­ PR c vised that these mixed rare earth fluorides are about $2 198 per pound. In 1970 the Bureau of Mines projected rare earth oxides to increase at the rate of approximately 1% per year compounded to 2000 in constant dollars. Using a $2.00 base and a compound increase rate of 1% per year, we project $2.20/lb in 1985 and $2.50/lb in 2000 both in constant 1976 dollars. Boron 282 The Chemical Marketing Reporter lists anhydrous sodium borate at $0.l25/lb. Boron prices are projected to remain constant, so the $0.125/lb figure is projected to the year 2000. Cesium and Rubidium These metals and their salts are produced and sold in such small quantities that prices are quite high and projec­ tions could not reflect volume prices. Therefore, practical consideration of these two elements for large scale applica­ tions would require study of sources and recovery techniques.

­125­ C. Non-Accountable Costs and Benefits As a result of emphasis on social relevance in recent years, there is a general awareness that all costs and bene• fits to society may not be accountable in financial ledger fashion. Yet, non-accountable factors should be weighed during consideration of introduction of new technology. inherent to the heat storage concept, and discussed in detail by others, is the notion that this technology is an essential ingredient if certain, new, renewable energy re• sources, such as solar energy, are to be realized. Thus viewed, heat storage would contribute to non-accountable benefits in terms of increased energy independence, reduced air pollution, decreased potential of weather modifications, and increased energy options. In some people's view, wide• spread, renewable energy resources might preclude the neces• sity of pervasive dependence on nuclear technology, and this would give them an increased sense of security.

In cases where heat storage may be used on a large scale, large accumulations of the heat storage medium will be required. Because it is not consumed, this material in a sense is stock• piled for use in the future. Many materials are now stockpiled by the Government, including fluorine as well as some of the metals under consideration. However, these materials are not put to use while in stockpile. They would be more valu• able to the Nation if they could be used in a non-consumptive fashion, such as heat storage, so that they might be held profitably for future use.

in regards to the metal fluorides, an additional social benefit is that they could be produced from a material that is now a waste product and vented to the atmosphere as well as dumped into rivers. Recovery of this material would save the fluorine for future use, and it would remove an aggressive chemical from the environment. Few if any negative environmental impacts can be imagined for the heat storage technology, while storage of valuable

-126- material represents accumulation of real assets that will accrue in value and against which loans may be obtained.

-127- VI. CHEMISTRY EVALUATION A. Classification and Data Quality The scope of this study is limited to materials containing fluorine. These materials can be considered under the following classifications: Single salts containing fluorine Binary mixtures of fluoride salts Ternary mixtures of fluoride salts Quaternary and greater mixtures of fluoride salts Binary mixtures of fluorides and non-fluorides Ternary mixtures of fluorides and non-fluorides Quaternary mixtures of fluorides and non-fluorides The number of combinations of compounds that are possible is quite high. We have exercized judgement in selecting the mixtures for study. For example, salts and salt-mixtures were generally not considered if they had more than one of the following characteristics: o Very high cost o Extreme toxicity, such as is characteristic of radioactive elements • Extremely poor availability Exceptions were made for materials for which there is good thermophysical data that might help in the understanding and prediction of data of more likely candidate fluorides. Consideration of mixtures of fluorides with non-fluorides was limited to the chloride, hydroxide, carbonate, and oxide containing materials. A systematic search for mixtures with the non-fluorides was not attempted. References do not necessarily refer to the original litera• ture. In many cases data were obtained from compilations. When the original literature was consulted, we often found that data presented without qualification in secondary sources really

-128- was calculated and not experimental. The-data consequently can only be considered to be order-of-magnitude indications and are not suitable for detailed engineering design.

-129- B. Metal Fluoride Synthesis Currently, most metal fluorides are derived from fluorspar, by way of the reactive intermediate compound, hydrofluoric acid. The acid reacts with varying efficiencies with metal oxides, metal carbonates, metal hydroxides, metal chlorides, and the metals themselves.

/^M20 ­> MF + H20

I M2C03 > MF + H20 + C02t H SO CaF2 -=■ 2­> HF + •<< MOM H > MF + H20 I MCI > MF + HClt

V MM > MF2 + H2 The routes starting with the oxide, carbonate, and hydroxide are the most common, and the choice is often determined by the availability of the most economical starting material. Sometimes the oxides are not very reactive, but the carbonates and hydrox­ ides are almost always reactive. In certain cases, the water produced as a by­product is difficult to remove without hydrolysis of the metal fluoride. In these cases, reacting anhydrous HF with the metal or metal chloride is appropriate, because the hydrogen and hydrochloric acid by­products of these reactions are easily removed.

In fact the reaction of the metal with HF can be the most desirable if the metal is inexpensive relative to its salts and it is higher than hydrogen in the electromotive series. The metal must be finely divided or reaction is slow or incomplete because of formation of a fluoride coating on the metal surface that pre­ vents further reaction. Reaction of the chloride with HF may be the method of choice when the chloride is readily available, when the product from a carbonate, oxide or hydroxide reaction cannot be separated from the water of reaction without hydrolysis, and when direct reaction with the metal is impossible or impractical. This exchange

­130­ reaction usually goes to completion but suffers from problems due to the HCl generation. It would require careful control to separate the product HCl from reactant HF or a high neutralization cost would result. Other conventional routes for metal fluoride preparation include the reactions of metal chlorides or metals with molecular fluorine, F„. Although this is a facile reaction with few separation problems, it is suitable only for small scale prepara• tions because of the high cost of the elemental fluorine. Lithium Fluoride Lithium fluoride is commercially prepared by the ambient neu•

tralization of bases such as LiOH, LiHCO.,, and Li2C03 with aqueous HF. Special care is taken during the neutralization process so that an excess of acid is avoided to prevent formation of LiF«HF. The neutralization process is carried out in a steel reactor lined with rubber or carbon bricks. Trace metallic impurities can be avoided by using lined equipment. Water is then removed under low pressure, or sometimes spray-drying is used. Because the very high purity LiF prepared in this way does not form any hydrates, it is easy to dry, store, and ship in an anhydrous form. Sodium Fluoride The commercial preparation of high purity NaF is similar to that of LiF. It is prepared by reacting soda ash (Na_CO_) or caustic soda (NaOH) with aqueous HF. Extreme care is taken during the neutralization process and the pH is properly controlled so that the formation of NaF'HF is avoided. As the solubility of NaF is relatively low, about 4.2 g/100 g water at room tempera• ture, a slurry is formed during the neutralization process. The slurry is either centrifuged and the solid is thermally dried to remove the water of hydration or the whole bulk is spray- dried. The mother-liquor left after centrifugation is recycled. The reactor and equipment used in the above process is mostly

-131- rubber or plastic lined. Sodium fluoride is obtained in 99% or higher purity. Low grade sodium fluoride is produced by roasting a mixture

of CaF2 and Na2C03 followed by extraction of the NaF. The dilute solution of NaF is spray-dried and 95-98% pure NaF is obtained. From an energy point of view this process appears to be least attractive because a substantial amount of energy is required in roasting and evaporation. On the other hand, the acid-base neutralization is an exothermic process and the liberated heat helps to concentrate the neutralized solution. No external source of energy is required until the sample is ready for fil• tration or spray-drying. Potassium Fluoride

C0 Potassium fluoride is prepared commercially by reacting K2 3 or KOH with aqueous HF. In this process, the neutralization point is judged very carefully because concentrated solutions of both KHF„ and KHCO- are stable in the presence of each other. After neutralization, the hot concentrated solution is passed over a heated rotary drum dryer. Extreme care is necessary in the handling of anhydrous KF as it is a hydroscopic material forming

KF«H20 easily. Wherever the use of KF (anhydrous) is required, it is always advised to pre-dry it at 200°C under an atmosphere of dry nitrogen. Reactors and other equipment used in this process are similar to the ones described in the NaF and LiF processes. Rubidium and Cesium Fluorides Both of these compounds are produced only on a small scale because of limited demand and various problems involved in obtain• ing high purity materials. As a result, the quality of the mate• rials available in the current market is low and price is very high. The major problems involved in the syntheses of RbF and CsF i are as follows:

-132- 1. Formation of stable hydrates and acid fluorides, e.g. CsF.HF, M. P. 142°C, which looses HF at 500-600°C. 2. Very high solubility of RbF and CsF in water. 3. Very low dissociation pressure of the acid-fluorides. In spite of the above problems, several methods have been developed for the syntheses of RbF and CsF. Process A: Very high purity CsF and RbF can be prepared by reacting CsCl and RbCl with elemental fluorine at an elevated temperature. Process B: Metal carbonates or hydroxides can be reacted with anhy• drous HF. To avoid an excess of water from the system, addition of a large excess of HF should be avoided. The acid-fluoride solu• tion is removed carefully under reduced pressure and the solid is dried at an elevated temperature. At the end of the process, fluorine treatment is given at 200°C to convert small impurities such as Cs^O and Rb_0 to CsF, RbF, residual water, and HF. Berylium Fluoride This compound is readily prepared in solution by dissolution

of BeO, Be(0H)2, or BeC0~ in aqueous HF. In the presence of excess HF, it has a tendency to form BeF_ and BeF. ionic species. Even careful evaporation of solution to dryness produces a material which is either deficient in fluorine or has an excess of fluorine. Major impurities present in solid BeF_ are BeO, and BeF_«X HF. The vapors of BeF_ are extremely toxic and care must be exercised to prevent inhalation of these toxic vapors when the solid is heated. Macpiesium Fluoride This compound occurs in nature as the mineral Sellaite. Magnesium fluoride resembles CaF_ and is commercially prepared by dissolution of MgO or MgCO-. in aqueous HF, filtration of the hot solution and drying. The purity of the commercial grade is about

92%. High purity MgF2 can be prepared by grinding a mixture of

-133- MgCl_ or MgSO. with KF and initiating the reaction by heating the mixture between 25-100°C. Once the reaction starts, there is a spontaneous rise in the temperature and the reaction proceeds with ease. After the reaction is over, the mixture is washed with liberal quantities of water to remove KC1 or K-SO.. Because the solubility of MgF_ is very low (0.076 g/1), there is not any appreciable loss by this process, and a purity of 99% is achieved.

25-100°C MgCl2 + 2 KF > MgF2 + 2 KC1 i> ^ Insoluble Soluble t t MgSO. + 2 KF > MgF2 + K S04 These reactions can be carried out in mild steel or stainless steel reactors. The latter is preferred. The corrosion experienced by 321 stainless steel (25% Cr and 1-3% Ti) in these open-air proc• esses is only 0.8-1.0 mm/year, despite wall surface temperatures that reach 600-650°C.

A technical grade of MgF2 can also be prepared by reaction

of CaF2 with 35% MgCl solution under pressure at 178°C and agitation of the mixture at intervals. After 3 hours, the reaction mixture is removed, diluted with at least twice its volume of water and allowed to settle for 12 hours. The liquid is decanted and the slurry is centrifuged. The cake is washed several times

and then dried at 110°C. This produces 97 to 98% pure MgF2 and

the major impurities are unreacted CaF2, MgO, water, and CaCl2. Calcium Fluoride Calcium fluoride occurs in nature as the mineral known as Fluorspar. It is mined and processed as per requirement.

A research grade, high purity CaF2 can be prepared by diges• tion of freshly precipitated CaCO, with an excess of aqueous HF and then centrigugation of the slurry. The retained cake is washed several times with water until the pH of the filtrate is

-134- close to 7. The cake is dried in an oven for several hours until

it is free of water. It can also be prepared by fusion of CaCl2 with KF or a mixture of KF^KCl. The fluorides of Ca, Mg, Ba, and Sr are gelatineous and difficult to filter when precipitated from cold solutions, but more granular products are formed if the precipitation is carried out from hot solutions. Optimum crystals are best made by fused salt reactions. Barium Fluoride

Very little BaF_ is manufactured commercially. Its charac• teristics resemble those of MgF2 and therefore all the earlier processes described under MgF„ can be used. It can be prepared by reacting BaCO_ or Ba(OH)_ with aqueous HF or by addition of KF solution to BaCl~ solution. BaF„ is sparingly soluble in water and therefore impurities such as unreacted BaClp and KC1 can be removed easily. The precipitate thus formed can be digested, filtered and dried.

BaC03 + 2 HF > BaF2 + H20 + C02

aqueous BaCl + 2 KF -> BaF2 + 2 KC1

aqueous Ba(N03)2 + 2 KF > BaF2 + 2 KN03 90-1 DOT Fusion process: BaCl2 + KF > BaF2 + 2 KCl solid solid

Strontium Fluoride Very little strontium fluoride is produced by the chemical industry because of limited demand. However, it can be prepared by routes similar to those of MgF_, BaF_, and CaF2# Similar types of impurities can be expected.

SrC03 + 2 HF > SrF2 + H20 + C02

SrCl2 + 2 KF > SrF2 + 2 KCl

Sr(N03)2 + 2 KF > SrF2 + 2 KN03

-135- Lead Difluoride Lead difluoride is very readily prepared by reaction of

PbCO., or Pb(OH)2 with a large excess of aqueous HF. The solvent is vaporized and the solid is dried in an oven between 110°- 150°C.

Pb(0H)2 + 2 HF > PbF2 + 2 H2 0

PbC03 + 2 HF > PbF2 + H20 + C02

PbF_ can also be prepared by mixing a solution of KF and

Pb(N0_)2 or Pb(CH C000)2. The slurry is centrifuged and the cake is dried between 110°-125°C.

aqueous Pb(N03)2 + aqueous KF > PbF2 + 2 KF

pbF + 2 CH C00K aqueous Pb(CH3COO)2 + aqueous KF > 9 3

If the starting materials such as PbCO,. and Pb(0H)2 are pure or the nitrate and acetate are removed from the starting material by extraction, 99.9% pure PbF_ can be obtained by these processes. Zinc Fluoride Hydrated ZnF~ is commercially prepared by reaction of ZnO , with 40-50% aqueous HF. In this process, the reactor, lined with polypropylene, is charged with aqueous HF and ZnO is added slowly. The reactor is cooled by brine because the reaction is exothermic and otherwise would melt the liner. After the stochiometric amount of ZnO is added, the mixing of the chemicals continues. The ZnF» slurry is kept in the reactor overnight whereupon all ZnO is

onverted to hydrated ZnF2« After the reaction is completed, the slurry is centrifuged and washed several times to remove soluble impurities. The hydrated ZnF_ is removed from the centrifuge ^nd dried for several days under a current of hydrogen fluoride

.. give ZnF2. Cobalt Fluoride Cobaltous fluoride is readily prepared in commercial quanti• ties by reaction of CoC03 with anhydrous HF. The reaction is

-136- exothermic and evolution of C0_ tends to carry along HF. After the reaction is over, the mixture is stirred a short while and let to stand for several hours until solid and liquid layers separate. The liquid is decanted and the slurry is heated slowly

until monohydrate CoF2 is obtained. The monohydrate is dehy• drated at 150°-200°C in a current of anhydrous HF.

CoC03 + 2 HF > CoF -HO + CO f

CoF «H 0 > CoF (anhydrous) Z 200°C Anhydrous CoF_ is not hygroscopic so once it is dry it can be handled in the open atmosphere. Nickel Fluoride. Manganous Fluoride, and Cupric Fluoride All of these compounds are prepared from the respective metal

carbonates in a similar way described for CoF2. All the hydrated fluorides are dehydrated in a current of anhydrous HF at various temperatures, NiF.«xH 0 is dehydrated at 500°C; MnF «xH 0 at 250°C; and CuF «xH 0 at 200°C. To, produce very high purity CuF_, i.e. 99.5% or better grade material, the product is loaded in a Ni or Cu reactor and elemental fluorine is passed over it at 200°C, thus converting traces of CuO to CuF_. Copper fluoride is very hygroscopic and needs to be handled in a nitrogen atmosphere all the time. NiF2 and MnF2 are not hygroscopic and therefore can be handled in the open atmosphere,

MC03 + 2 HF > MF2«xH 0 + CO^

MF -XH O > MF_ Z Z A Z Ferric Fluoride, Titanium Tetrafluoride, Zirconium Tetrafluoride, Aluminum Fluoride, and Chromium Trifluoride All of these compounds are produced by the halogen exchange method. Metal chlorides, which are very inexpensive raw materials and are readily available, are reacted with anhydrous HF at an

-137- ambient temperature except for A1C13 and CrCl., which require higher temperatures for reaction on initiation. The initial reaction is very vigorous and a substantial amount of HCl is liberated that carries off HF. As a result this process requires 3 to 4 times more HF than the theoretical amount or, on a large scale, will require HF/HC1 separation and recycling. As the metal fluorides are formed, the rate of the reaction decreases and mechanical mixing is required. After certain intervals, the presence of chloride ion is checked and when necessary more anhy• drous HF is added. At the end of the reaction the rate becomes so slow that either external heating is required or the mixture must stand for several days before further processing. After all the chloride has been removed, the slurry is filtered and dried under an atmosphere of nitrogen to avoid the formation of oxides and oxyfluorides. Titanium tetrafluoride and zirconium tetra- fluoride prepared by the halogen exchange method are of very high purity while iron trifluoride (FeF_) has traces of chloride and

is low on iron. Typical purity of FeF3 is 97-98% while TiF. and ZrF. both are obtained in 99% or better grade. If anhydrous HF

is passed over A1C13 at 100-150°C for 2 days, followed by ele• mental fluorine for a few hours, 99.5-100% purity is achieved.

The reaction of anhydrous HF with CrCl3 is carried out at 500-

600°C to give CrF3 in 99-100% purity.

Ferric Fluoride The trihydrate of ferric fluoride is readily produced by

either reaction of FeCl3«6H20 or Fe203 with anhydrous HF. The reaction between Fe.O. and HF is preferred over the one with FeCl_«6H 0 which requires the removal of HCl and 3 moles of water. Ferric fluoride trihydrate produced by this method is always

accompanied by unreacted Fe20^ or FeCl3. Dehydration of FeF3«3H20 at elevated temperatures has not been.proven. Therefore further development work is required for production of anhydrous FeF_ by this method.

-138- Aluminum Trifluoride

One of the commercial routes to A1F3 is the reaction of about 15% aqueous HF with aluminum oxide. The HF is charged into a polypropylene lined reactor and A120_ is added at such a rate that the temperature does not exceed 85°C at any time. Alumina addition is continued at a slow but continuous rate until white precipitation appears. Only 90% of the theoretical amount of A1_0_ is added before the reaction is stopped so that low pH is maintained, preventing precipitation of Fe 2 + from the solution (commercial grades of alumina always contains substantial amount of Fe 2+ ). After completion of the addition of ALO., the reaction mixture is stirred overnight, which brings the tempera• ture down to about 38°C or less. The slurry is centrifuged and the cake is washed with water until free from HF. It is then dried at 60°C for 3 to 4 hours.

A1203 + aqueous HF > 2A1F3»3H O The resulting aluminum fluoride trihydrate can be dehydrated at an elevated temperature in the presence of anhydrous HF but

A1203 or oxyfluoride are still formed, giving lower values of fluorine. Typical purity of AlF3 produced by this method is 92%. Ferrous Fluoride

Anhydrous FeF2 is most conveniently prepared by passing anhydrous HF over metallic iron at red heat or at lower tempera• tures over FeCl2« It is also prepared by reacting FeS04«6H20 with anhydrous HF and washing the precipitate with anhydrous HF and then drying carefully under nitrogen.

Anhydrous FeF0 prepared by these routes always has small +2 amounts of Fe_0_ and FeF_ present in it. Oxidation of Fe to +3 Fe occurs very readily.

-139- Stannous Fluoride This compound is commercially prepared by reaction of tin powder, finely divided tin, or tin oxide with anhydrous HF. After the reaction is over, excess HF is removed and the product is transferred to an aqueous mother-liquor. If acidic, the mother-liquor is neutralized with SnO. After the neutralization, the mother-liquor is pumped to a crystallizer where it is allowed to stand overnight. Major impurities are H_0, SnF., FeF?, CuF2, and NiF_. The commercial grade of SnF„ is 98% pure. Sodium Monofluorophosphate Commercial sodium monofluorophosphate is prepared by direct fusion of NaF and NaP03 at 700°C. Major impurities in Na2P0 «F are starting materials such as NaF and NaPO_. The commercial grade Na2P0_F has about 1.2% Free F and the purity varies between 95-97%.

New Less Expensive Metal Fluoride Syntheses Research to prepare metal fluorides directly from fluorspar, avoiding the expensive HF production step, has progressed to the point that such reactions have been carried out successfully on a laboratory scale and in some cases, on a small commercial basis. For example, fluorspar and metal carbonates under high pressure give metal fluorides directly:

PreSSUre CaF2 + M2C03 > 2MF + CaC03

Another reaction has been shown to give 98% pure sodium tetra- fluoroborate in good yield by the combination of fluorspar and boric acid (or borax) and Glauber's salt:

CaF2 + H3B03 + Na2S04.12H20 > NaBF4

These routes, if successful on an industrial scale, would result in production costs lower than those discussed in the cost section

-140- =ind used to calculate the metal fluoride prices given in Tables XXV and XXXVI. Preparation of metal fluorides also can be achieved from fluosilicic acid in several ways, as outlined on page 41. Quite a large number of patents have been filed covering the preparation of many fluorides by these methods. Currently, A1F_ and Na_AlFc are prepared from fluosilicic acid in industrial quantities. The primary hurdle in this area is achievement of sufficient purity for heat storage purposes, but indications are that the required purity will be met. The principal possible impurity is silicon dioxide.

H„SiF, + 6M0H > 6MF + SiO~ + 4H_0 2 6 2 2 Various techniques would be required for its removal, depending on the solubility of the metal fluoride. In the case of sodium fluoride, for example, the Si02 is crystallized first and separated; then the NaF is crystallized to give >99% purity. A second attractive route to metal fluorides from fluosilicic acid is via ammonium fluoride: NH H.SiF^ —=-s > NH„F MOW > MF + H_0 + NH_ 2 6 4 2 3

The Si09 is separated from the ammonium fluoride before the metal hydroxide (or oxide or carbonate) is added. The ammonia is recycled, and high purity metal fluoride is readily obtained. The great deal of interest shown in these reactions over a period of years indicates that they probably could be scaled up to commercial proportions in a systematic and facile manner. Once the metal fluorides are prepared, by whatever method, and purified, they must be thoroughly dried for heat storage purposes. The dried fluorides will then be handled in a dry atmosphere until they are sealed in their containers. Mixtures can be prepared easily by weighing the components and thoroughly

-141- stirring them mechanically, as powders, until intimate mixing is achieved. They will then be ready for introduction to the heat storage container. One or two melt-thaw cycles will complete the mixing.

-142- C. Purification Current manufacturing processes produce metal fluorides in various degrees of purity. The three basic sources of impurities are corrosion of the process equipment, the raw materials, and undesired chemical interactions:

Impurities I T1 1 Equipment Chemical Raw Materials Nature I 1 1 1 Oxidation Hydrolysis Decomposition Incomplete Reaction Most of the equipment currently used in the manufacture of metal fluorides is made of mild steel, stainless steel, Hastelloy C, nickel, or Monel. The common impurities produced by corrosion of these materials are the fluorides, oxides, and oxyfluorides of Fe, Ni, Co, Cu, Cr, Mn, Mo, and Silicon. Because the solubilities of these solid and non-volatile impurities are low in HF and organic solvents, it is very difficult to separate them from the desired products. In many cases, it is possible to solve this corrosion problem by lining the equipment with non-reactive materials such as rubber, plastic, graphite, or ceramics. Most of the raw materials that are available on a commer• cial scale contain the ore impurities, contamination from reactor materials, metals that are closely related (i.e. the metals of the same group or ionic radii), and impurities that are in hydrofluoric acid. Fortunately, the raw materials that were discussed in the previous section are available in 98% or better purity, and quality control of the reactants can result in improved product purity. Ionic impurities such as chloride, bromide, nitrate, and sulfate species can be removed by washing with anhydrous HF. Chemical oxida• tion proceeds easily in the case of elements that are multi• valent, especially if the metal fluoride is prepared at

-143- elevated temperature or the heat of the reaction is high and the system is open to the atmosphere. Under such circumstan metal fluorides become contaminated with oxyfluorides, oxides, or higher valency metal fluorides. The oxyfluoride and oxides can be converted to metal fluorides by reaction with anhydrous HF at elevated temperatures and preferably in a fluidized bed system. The higher valency metal fluorides can be reduced to lower valency fluorides by heating with metal powder or by

reduction by hydrogen. SnF2 and FeF2 are two compounds under consideration that are likely to be oxidized during the normal process of synthesis and therefore their manufacture should be carried out under an inert atmosphere. Other metals such as Co, Ni, Cu, and Mn would require much more vigorous conditions for oxidation to the higher valency state than are used in the production of their fluorides. Almost all the metal fluorides react with water at ele• vated temperatures and produce oxyfluorides and oxides. Hydro• gen fluoride is generated during the hydrolysis process and builds up pressure in a closed system. Special care should' be exercised in the handling and transfer of the raw materials which, hydrolyze readily. It is possible to convert most of the metal oxyfluorides or oxides to metal fluorides by reac• tion of these materials in a current of anhydrous HF at elevated temperature:

MF„ + X.H90 Open or Closed System ( } + x.Hp n 2 A n-x x

< In the presence of excess anhydrous HF at elevated temp, and open flow system. When the syntheses of metal fluorides are not carried to completion, various quantities of reactants may contaminate the product. The best remedy for this problem is to complete the synthesis process by adding excess HF, increasing reactic temperatures, proper mixing, as well as other methods of con-

-144- trolling the rate of the reaction. After the metal fluorides are manufactured, a number of procedures can be followed that will reduce impurities. Recrystallization can be successively repeated. Volatile materials and some waters of hydration can be removed by heat and vacuum. Thermal treatment is also often useful for con• verting metal hydroxides to metal oxides. Sparging with HF and H2 has been used many times to reduce the concentration of oxide compounds. Fusion in a vacuum of the fluorides with NH.HFp or KHF_ is also effective for removing oxides. These compounds decompose and liberate HF, which reacts with the oxides to form water vapor. Water is then removed by the vacuum.

2KHF ,+ MO ^Z 2KF + MF2 + ^0^

Reaction of impurities with bromine pentafluoride or silver halide also reduces their concentration., but use of these materials may not be cost effective. Finally, impurities can be removed by reactions with active metals, such as aluminum.

-145- D. Vapor Pressure and Thermal Stability Use of metal fluorides for thermal storage is practical only in closed containers. Any appreciable vapor pressure, then, would either buckle and rupture the container or would require reinforced (and therefore expensive) container con• struction. Fortunately, many metal fluorides have very low vapor pressures, even at temperatures of 100° above their melting points. Some of the vapor pressure data reported in the literature are presented in Table XXII.

Vapor pressure can develop in three ways: 1. Simple vaporization of a solid or liquid to a gas 2. Disproportionation of the solid: 2MX > MX . .. (gas) + MX . (solid or gas)38 n n + l n—l 3. Decomposition of the solid: op MXn(solid) > MXn _ x(gas) + 1/2 X2(gas)°° Process 1 is acceptable so long as the vapor pressure does not exceed equipment design strengths. Simple vaporization is completely reversible and does not modify the heat storage media characteristics. However, processes 2 and 3 cannot be tolerated. They generally represent not easily reversible processes that would change the heat storage media composition, melting point, heat storage ability, etc. Even small vapor pressure values for a heat storage media require analysis of their causative natures because if they result from decomposition, they may lead to long term modification of essential characteristics. 1. Ammonium Salts Ammonium salts, such as ammonium tetrafluoroborate, ammo• nium hexafluorosilicate, ammonium fluoride, ammonium hexafluoro- ferrate, and ammonium hexafluorotitinate are unacceptable because of decomposition, evidenced by high ammonia vapor pressure:

-146- TABLE XXII. VAPOR PRESStJRE OF FLUORIDE SALTS

Malting Vapor Pr«assur e (mm Rq) Other Point At Another Temperature Vapor Pressure Expression Salt CC) At MP Temperature CC) (T - *K) log P - Ref.

LiF 848 0. 37 0.255 948 8.797 - 11.409T"1 96 0.28 948 117 NaF 996 0. 366 1.938 1096 9.4188 - 12.428T-1 96 0. 415 2.158 1096 99 2.09 1096 117 0. 00003 1 CaF2 1418 0. 0003 0.0002 1460 8.8930 - 21.826T" 96 0. 087 0.399 1460 79 0. 074 0.387 1460 99 BaPj 552 0.041 903 79 2. 05 7.96 868 10.651 - U.125T"1 97 5.55 850 112 18.3 900 9.136 - 9. 236T-1 117 89. 1010 11 RbF 795 152. 1200 117 0. 368 2.65 875 99 1 ZrF4 932 4.90 1032 12.542 - 11.360T" 117 AlFj Sub. 86.3 1094 1 13.927 - 16.943T"1 117 6.9 1000 97 3.006 1000 112

MgF2 1263 15.3 1700 117 1.0 1467 139

Ma3AlF6 1012 1. 9 97

KBF4 570 1. 92 14.27 ' 670 97

HaBF4 406 281.2 600 97

NH4BF4 Sub. 3727 8893

50NaF/50ZrF4 510 <2 700 117

45KF/55ZrF4 275 14.3 800 117

59.6KF/40.42rF4 550 16.7 1050 117

59BeFa/41ZrF„ 0.94 800 117 40BeFj/60ZrF4 0.09 800 117 25BeF2/75ZrF4 0.02 800 117 KF-HF 234.6 4. 90 97 HiFj 1100 67.9 1283 285 -1 SnF2 219.5 6.726 - 6.951T 270 -1 ZnF2 875 6.43 - 1.318T 284 AlF3 Sub. 6.9 1000 97 Na2SiF6 Dae. 19.3 516.3 97 BaSiF6 330d 29.0 417 97

-147- NH4BF > NH3 + HF + BF3

(NH4)2SiF6 > 2NH3 + 2HF + SiF4

(NH.)3FeF6 > 3NH + FeF3 + 3HF

(NH4)2TiF6 > 2NH3 + 2HF + TiF4

2. Tetrafluoroborates

In general, the dissociation pressure of BF3 increases rapidly over tetrafluoroborate compounds about 50-100° above their melting points. Yet, molten NaBF4 and mixtures of NaBF. and NaF have received serious consideration as reaction media at Oak Ridge, indicating that this problem may not be serious with the more stable tetrafluoroborates or with mix• tures of them that melt below the melting point of the single salts. 3. Fluorosilicates The available data for individual fluorosilicates indicate that these materials are unsuitable for heat storage applica• tions at high temperature. The reason for this is the decom- 78 26 9 97 position of fluorosilicates to give gaseous SiF4 ' '

M2SiF > 2MF + SiF4

The vapor pressure of SiF4 above Na2SiF at 516.3°C is 19.3 mm and above BaSiF, at 417° it is 29.0 mm. 6 On the other hand, these decomposition reactions may have great utility in the synthesis of pure metal fluorides from phosphate rock. Isolation of the metal fluorosilicates could be followed by a baking process that would drive off the silicon tetrafluoride, leaving the metal fluoride. Lithium hexafluoro- silicate is known to decompose completely at 350° in dry air. Alkaline earth fluorosilicates break down similarly at relatively low temperatures (350-550°). Potassium fluorosilicate decomposes by a slightly different route, first forming K3SiF? at 700-750°F which in turn decomposes above 800°:

-148- 700-750° 3 K_SiF > 2 K SiF + SiF. 2 6c 03 7n 4

>800 K3SiF? °> 3KF. + SiF4

Nevertheless, the low cost and ready availability of these materials are sufficient incentives for a further evaluation of their potential for heat storage at lower temperatures. In some cases it is possible that eutectic mixtures con• taining fluorosilicates might not give off SiF., because their melting points would be lower than those of the single salts and the tendency to volatilize would be lower. 4. Fluorotitanates Titanium oxydifluoride is prepared by the reaction of 270 either anhydrous or aqueous HF with titanium dioxide, an abundant and low cost material:

Ti02 + 2HF > TiOF2 + H20 Unfortunately, it is thermally unstable, decomposition occurring 271 at 150-200°C. Hexafluorotitanates are interesting because of potential low cost. Examination of some of their vapor pressure trends is instructive: Lithium hexafluorotitanate dissociates above 600°C to give LiF and TiF.. Sodium hexafluorotitanate begins to decompose at 760° and completes decomposition at fusion at

804°. Above 817°, the vapor pressure over K2TiF- is too high to permit thermodynamic data determinations in experimental chambers. Similarly, mixtures containing Li?TiF are thermally unstable, although the rates of vaporization are much lower.

However, eutectic mixtures of Na_TiF and K_TiFfi are stable, and vapor pressures are low, even on melting, so long as the composition is not predominantly TiF.. Therefore, many eutectic compositions of fluorotitanates are heat storage candidates, even though the individual salts cannot be consid• ered.

-149- 5. Aluminum Compounds Complex aluminum compounds can be considered in the same way: Aluminum trifluoride vaporizes reversibly without melting (sublimes) and is therefore unsuitable as a thermal storage candidate as a single salt in non-reinforced containers. Its eutectic and congruent mixtures with certain other fluoride and non-fluoride salts, however, are potentially of interest.

Cryolite, Na_AlFfi, the congruently melting compound of A1F_ and NaF, is well known, has been used extensively in industry* has a high heat of fusion, and is stable in dry atmospheres. Quite a variety of aluminum-containing fluoride mixtures and compounds are available for consideration, but few heats of fusion of them have been determined. Some of these candidates and their melting points are given in Table XXIII. Although this class of materials seems quite promising, it must be evaluated carefully. For example, it has been found that

formulations are thermally unstable in which AlFfi octahedra are linked into chains through their corners. Thus: ppn o CaAlFc > A1F_ + melt D J /J739° NacoAlF n1 4. * > Na-AIF3 ^6 + melt O/QO Na2MgAlF7 > NaMgF + MgF2 As is the case for the fluorotitanates and TiF., the fluoroaluminates with high percentage of A1F- are expected to have high vapor pressures, requiring any selection of aluminum fluoride mixtures to be limited to compositions that are not predominantly A1F_. 6. Fluoroferrates Although iron trifluoride has a high vapor pressure, its complex salts are expected to have lower vapor pressures. A variety of hexafluoroferrates have been prepared, such as:

M3FeF6, M=K, Na, Li, Cs, NH4? M' (FeF6)2, M'=Cu, Ba, Zn;

MM'FeFfi and mixtures of these. Little thermodynamic data have

-150- Table XXIII. Melting Points of Some Aluminum Fluoride Compositions

Composition MP (°C) Reference

Na-AIF^ . 1009 97 3 6 Li3AlF6 785 135 K^A1F 3 6C 930 81 Rb_AlF 3 6c 985 112 Cs-.AlF^ 3 b 823 112 80 Li A1F /20 BaCl2 840 115

38.1 Na3AlF /61.9 NaF 889 49

52 Na3AlF6/48 CaF 945 20

37.5 Na3AlF6/62.5 A1F3 694 129

57.5 Na3AlF6/42.5 MgF2 921 114 32.3 Na AlF /9 A1F../58.7 CaF„ 682 42 03 cb 3 2. 33.9 Na3AlF6/66.1 Li A1F, 725 114 Na_AlF3 c6/K_AlF 3 6c 952 114 11.3 Na3AlF6/88.7 NaCl 734 129

42.5 K3AlF6/57.5 MgF2 930 81 85 LiF/15 A1F 706 141 85.7 NaF/14.3 A1F' 882 19 93 KF/7 A1F 848 116 55 KF/45 A1F 560 118 40 LiF/17 NaF/43 AlF 600 118

-151- been uncovered for these materials. Although they are pH sensitive, they appear to be thermally stable at their melting points with the exception of the ammonium salt.

-152- E. Hydrolvtic and Oxidative Stability All of the metal fluorides interact with water at high temperatures. Lithium fluoride is perhaps the most stable in this respect, as molten LiF can be poured directly into water without vigorous reaction. Some of the fluorides are hygroscopic, as exemplified by BeF_ and KF, whereas others, such as LiF and NaF are not hygroscopic. Many metal fluorides will form hydrates, such as KF.4H20, KF.2H20, A1F -H 0, and FLINAK, a eutectic mixture of LiF, NaF, and KF. The water of hydration can be removed from many fluorides, such as FLINAK, simply by heat and vacuum. Other hydrates, such as the aluminum trifluoride hydrate, are difficult to dry without forming metal oxide and hydrofluoric acid. Magnesium fluoride is hydrolyzed completely in moist air at 1150° for several hours, but is not effected in dry air. Calcium fluoride requires higher temperature and longer time for complete hydrolysis. Zinc fluoride quickly sinters extensively in dry air at 670-800°, but completely hydrolyzes to ZnO in moist air at the same temperature. Cryolite is completely stable in dry air but reacts with water at high temperature according to the following reaction:

2 Na0AlFc + 3 H_0 > 6 NaF + Alo0_ + 6HF 3 6 2 2. 3 In summary, metal fluorides in the molten state must be sealed in closed containers that are dry. A worthwhile added precaution would be to flush the container with inert gas before sealing. In regards to oxidative stability, most of the fluorides discussed in this report are stable in dry air, even at high temperatures. Among the exceptions, the most notable is FeF_. The ferrous ion is oxidized very easily to the ferric state.

-153- I

F. Corrosion For any heat storage medium, the choice of material of construction for the container is of critical significance in terms of system cost, lifetime, and performance. A high degree of corrosion resistance is required for long service life, but in general, the more corrosion resistant a material is, the higher is its cost. The compatibility of molten fluorides with various candidate container materials has been studied both by thermo- chemical calculations and by corrosion studies. 1. Thermochemical Calculations It is possible to assess the potential of certain metals as container materials by comparing the Gibbs free energy for the formation of their fluorides with the free energies of formation of the fluoride salt storage media.12 0 A listing of some of these free energies is given in Table XXIV. An analysis of the data presented in the table indicates that many fluorides that are being considered as heat storage media are more stable than the fluorides of the more common container metals copper, nickel, iron, and chromium. Certain other fluorides can be considered less desirable for heat storage on the basis of their corrosivity to the container materials. Those metal fluorides that have a free energy of formation less than or similar to the fluorides of the metals used for the container are expected to cause a great deal of corrosion.

For example, CoF2 seems to be a promising candidate on the basis of its heat of fusion/unit volume, but its free energy of formation (63.15 Kcal/gram atom fluorine at 1000°K) is close to those of the fluorides of the most probable metals used for storage containers (62.00 Kcal/gram atom fluorine for NiF_ and 67.82 Kcal/gram atom fluorine for FeF_ - both at 1000°K). The equilibrium reactions :

-154- TABLE XXIV. GIBBS FREE ENERGIES OF SELECTED FLUORIDES (-AG° kcal/mole per metal-fluorine bond) T °K Metal Fluoride 700 1000 Ref. LiF 131.3 124.3 95 NaF 120.1 112.6 95 KF 118.8 111.6 95

MgF2 116.3 111.2 95

CaF2 132.1 126.3 95

CoF2 68.0 63.1 95

CrF2 79.0 73.9 11 CuF 34.9 30.9 95

CUF2 52.0 46.6 95 FeF_ 72.7 67.9 95

FeF3 70.3 65.1 95

NiF2 65.0 59.3 11 MoF6c 54.2 50.9 120

A1F3 105.7 99.6 95

Na3AlF6 116.3 109.9 95

SiF4 90.5 87.9 11

ZrF4 100.2 94.5 11

UF4 101.2 96.2 11

KBF4 98.6 93.5 95

CF4 49.4 46.7 11

ZnF2 A* 80. d

d. Estimated.

-155- 1. Ni° + CoF2 ♦* NiF2 + Co°

2. Fe + CoF2 ♦* FeF2 + Co therefore would produce substantial quantities of Co , FeF2, and NiF2 and would result in considerable corrosion. For the same reason, many other transition metal fluorides including those of chromium, nickel, manganese, copper, and iron are not suitable as heat storage media in conventional metal con­ tainers. pkFo and BiF_ are known to be readily reduced by structural materials such as iron and chromium. Other metal fluorides can easily be partially reduced: Cr° + 2U4+ —> 2U3+ + Cr2+ Because of this corrosion route, any metal fluorides that can be easily reduced should not be used for heat storage. EuF3>

NbFc, SnF4, and MoF would be reduced similarly. Thus, problems can arise if corrosion is not considered in choosing a eutectic fluoride mixture. The container mate­ rial will be a primary factor in the cost of heat storage system and using a less corrosive fluoride salt may enable the use of less expensive alloys for the container. On this basis, primary consideration should be given to the alkali, alkaline earth, and silicon fluorides because they appear to be the most stable. Titanium fluorides and non­transition metal fluorides such as ZnF2, A1F3, SnF2, and PbF2 may be useful for heat storage on the basis of corrosive stability; however, more extensive corrosion cycling data must be gathered for these materials before a decision regarding their usefulness can be made.

Similarly, many of the rare earth fluorides may be useful because they form very stable trifluorides. However, certain of the rare earth fluorides, such as EuF_ are less stable. In cost­effective mixtures of rare earth fluorides, these com­ ponents would be selectively reduced, providing a possible corrosion pathway.

­156­ Although many low cost metals and alloys can be used for the containment of very pure fluorides, complications are pre• dicted to arise from impurities. For impure fluorides only, a limited number of metals can be used (e.g. nickel, copper, platinum, gold, and graphite) without some resultant corrosion. Certain impurities, however, can be tolerated. For example, metal fluorides manufactured from fluoapatite can be expected to contain SiO^ and SiF.- impurities, but because their free energy of formation is very high, they should not be sources of corrosion problems by direct reaction with the container. Practical, commercial grades of metal fluorides might contain a variety of impurities. Their practicality for direct use as heat storage media or the degree of purification re• quired cannot be predicted, but must be determined experimentally. 2. Experimental Corrosion Studies Much of the original work on container corrosion by metal fluorides was concerned with fluorides used in regenerative emf cell systems and .liquid fueled nuclear reactors, ' but some recent studies of corrosion in heat storage systems have been discussed. The fluorides investigated in these corrosion studies include: LiF, NaF, KF, CaF2, MgF2, ZrF4,

ThF4, RbF, BeF2, and UF4. A wide variety of alloys have been studied as container materials but most were predominately nickel, iron, or molybdenum. Other metals in these alloys include chromium, cobalt, aluminum, titanium, tungsten, niobium, zirconium, and columbium. Of these metals chromium is the most electropositive and is thus preferentially leached from the surface of the alloys by fused fluoride salts. ' In corrosion studies, the fluoride salts were found to contain a higher concentration of chromium than iron or nickel. The chromium was found to diffuse from subsurface regions at high temperatures, in addition to its selective removal from the metal surface. The chromium diffusion is more rapid along the grain boundaries and chromium is selectively lost in the grain boundary regions. This grain boundary effect extends

-157- into the metal to depths that are many times that of the simple surface corrosion by the fused salt. The diffusion of the chromium in these alloys produces voids below its surface because the other constituents cannot diffuse rapidly enough to replace it. The chemical reactions responsible for this corrosion may be classified into three types depending on the origin of the corrosive agent: 1. Impurities in the melt, such as water that reacts to form hydrofluoric acid or a metal fluoride with high AG,.; 2HF + Cr > H + CrF

2FeF3 + 3Cr > 2Fe + 3CrF2

2. Oxide films on metal surfaces: 3Zr0 + 4CrF 2Cr203 + 3ZrF4 > 2 3 2CrF + Cr > 3CrF2 3. Constituents of the fluoride composition:

Cr + 2UF4 > 2UF3 + CrF2

The formation of voids is initially quite rapid but then decreases until a straight line relationship exists between depth of void formation and time. In addition to time, the significant parameters affecting the corrosion of Ni-Cr-Fe alloys by fused fluorides are the operating temperatures and the surface area to salt volume ratio of the system. For

example, with NaF-ZrF4~UF (50-46-4 mole %) in an Inconel container for 1500 hr at 870°C, corrosion reached depths of 13 to 18 mils. With everything else constant, corrosion is decreased by a factor of two when the temperature is reduced to 653°C.

The corrosion reactions can cause property changes of the eutectic fluorides. For example in thermal conductivity studies of FLINAK (LiF/NaF/KF) using Inconel containers, corrosion caused a decrease in conductivity with time.19 1

-158- A listing of fused fluoride corrosion studies appears in Table XXV. In general, these data indicate that the rate of corrosion is very dependent on the type of container material as well as the particular fluoride salt being studied. The data suggest that a number of alloys look promising for the containment of fluoride salts. Those that partially consist of molybdenum or columbium have the best corrosion resistance. These more exotic alloys may be too expensive( for many high temperature heat storage applications. However, some research has been done to decrease the corrosion of less expensive alloys by either purification of the fluoride salts or by addition of a getter such as aluminum to the fused salt. The latter approach is reported to be quite promising. After long term treatment at 850°C (more than 10,000 cycles), aluminum treated mixtures caused no corrosion .to 316-type stainless steel. Studies of this type are continuing and offer the possibility that inexpensive fluoride containing 127 heat storage systems may be developed.

-159- TABLE XXV. FLUORIDE-METAL CORROSION EXPERIMENTS

Fluoride Time (hr) /Tem• Composition Container Material perature CO Comments Ref.

NaF-LiF-XF-UF. Inor 8 1000/900 Very little attack 267 (11.2-46.0-41.3-2.5 mole %) Ni-Mo-Cr (71-76) (15-18) (6-8) 20,000/700 2 mils 267 Temp, increase to 810* produced subsurface voids to 4 mils

LlF-BeP2-UF4 " 15,000/700 Corrosion complete after 267 (62-37-1 mole %) 5000 hr

NaP-ZrF4-UF4 Ni-Cr-Fe 3550/590-760 Pump studied working 267 (50-46-4 mole X) vanes and vanes in good condition 25,000/650 Impeller suffered consi• 267 derable cavitation damage

NaP-LiF-ZrF4 Ni alloys /500-600 Corrosion rate of 20-40 267 HF<*\F, also present mils/month

NaF-LiF-ZrF4 Inor -8 /500-600 Alloy corroded at a rate 267 (33. 5-33. 5-33 mole X) of 3 mile/month in vapor phase Pure Ni /500-600 18 mils/month in vapor 267 phase LiOH-LlP Inconel 550/650 0.27 nils/day 134 Ni-Fe-Cr M76-7-17 wt X) LiOH-LiP Pure Ni 550/650 0.027 mils/day 134

LiOH-LiF Variety Various Sulphate^silica irapurl- 134 ties increased the corro• sion rate. For Inconel 600 silica had little ef• fect. Sulphur bearing compounds are suspected of causing catastrophic failures of test contain• ers.

NaF-ZrF4-UF4 Inconel 1500/650 7 mils 117 Small voids 50-46-4 mole X) 1500/760 8 mils 117 Intergranular 1500/871 13 mils 117 Intergranular/large voids 1000/816 10-13 mils 117 Ni-Fe-Cr 1000/816 13-15 mils 117 (83-7-10 wt X) Ni-Fe-Cr 1000/816 12 mils 117 (76-14-10 wt X) Ni-Fe-Cr 647/B16 3 nils 117 (76-19-5 wt X) Ni-Fe-Cr-Mo 1000/816 2 mils 117 (74-10-6-10 wt X) Ni-Cr-Mo 1000/816 1 mil 117 (77-3-20 wt X) Ni-Cr-Mo 831/B16 0.5 mil 117 (75-5-20 wt X) Ni-Mo-Fe 1000/816 1-3 mils 117 (66-29-5 wt X) Baste Hoy B

-160- TABLE XXV. FLUORIDE-METAL CORROSION EXPERIMENTS (Continued)

Fluoride Time (hr)/Tem- Composition Container Material pexature (*C) I Comments Ref.

NaP-ZrF4-UF Ni-Mo 1000/816 0.5-2 mils 117 (76-24 wt X) (50-46-4 mole X) HaF-KF-LiF-UF., Inconel 1000/816 20 mils 117 Heavy, general inter- granular voids NaF-KF-LiF-UF. Ni-Mo-Al 1000/016 Heavy surface 117 (86.5-11.2-2.2 wt X) (11.2-41-45.3-2.5 mole X) Pitting - 2 mils Ni-Mo-Cr 1000/816 Heavy voids to 1 mil 117 (77.6-16.7-4.6 wt X) Haste Hoy B 500/816 No attack observed 117

NaF-UF4 Inconel 117 1000/816 15-10 mils (74-26 mole X)

NaP-ZrF4 Inconel 117 (60-40 mole X) 1000/816 6 mils

NaF-ZrF4-UF4 Inconel 117 1000/816 10-13 mils (60-28-12 mole X)

LiF-UF4 Inconel 117 1000/816 20 mils (74-26 mole X)

LiF-ZrF4-UF4 Inconel 117 1000/816 17-19 mils (50-46-4 mole X) 117 KF-ZrF4-UF4 Inconel 1000/816 7-8 mils (50-46-4 mole X) Inconel 117 RbF-ZrF.UF4 . .4 (50-46-4 mole X) 1000/816 9 mils

HaF-BeF2 Inconel 117 (50-50 mole X) 1000/816 7-8 mils

NaF-BeF2 Inconel 117 (70-30 mole X) 1000/816 4-6 mils

NaF-BeF2-UF4 Inconel 117 (50-47-3 mole X) 1000/816 ; 8-9 mils

NaF-BeF2-UF4 Inconel 117 (68-29-3 mole X) 1000/816 12 mils

LiF-BeF2-UF4 Inconel 117 (50-47-3 mole X) 1000/816 13-20 mils

NaF-LiF-BeF2 Inconel 1000/816 5 mils 117 (53.-24-23 mole X)

NaF-LiF-BeF2-UF4 Inconel 1000/816 8-9 mils 117 (33-33-31-3 mole X)

NaF-LiF-BeF2-UF4 Inconel 1000/816 13 mils 117 (52-24-22-2 mole X) 1000/816 4-6 mils 117 LiF-ThF4. inconel (74-26 mole X)

LiF-ThF4-UF4 Inconel 1000/816 IS mils 117 (74-24-2 mole X)

NaF-CaF2-MgF2 316-Stainless Steel /750 Corrosion by Cr reaction (65-23-12 mole X) void formation Purified

-161- TABLE XXV . FLUORIDE-METAL CORROSION EXPERIMENTS (Continued)

Fluoride Time (hr)/Tem• Composition Container Material perature CC) Comments Ref.

NaF-CaF2-MgF2 316-Stalnless Steel 10,000/750 No corrosion (65-23-12 mole X) Purified With Al getter (0.3 wt X)

LiF Cb-lZr 5000/816-1038 No corrosion observed. 9 (99-1 w/o) Ale alloy lacks suffi• cient strength for I.IF con• tainment at these tempera• tures.

LiF FS-65 5000/616-1038 No corrosion 108 Ta-W-Zr-Cb (26-10.5-0.9-60.6 w/o)

LiF SCb-291 5000/816-1038 Ho corrosion 108 Ta-W-Cb (10-10-80 w/o) LiF Cb-lZr 1000/816-1038 Sever distortion of bel- 109 lows used for containment attributed to differen• tial thermal expansion.

LiF Cb-lZr 3000/816-927 Serious deterioration of 109 Coated with Iron- bellows attributed to titanate the coating and differ• ential thermal expansion.

Li2BeF4 316-Stainless Steel 4300/6 50 1 mil/yr 268 Corrosion can be de• creased by adding a re- ductant such as Be metal. LiF/NaF 316-StainloBB Steel 3 times/day No deterioration in 280 for 4 years at equipment performance. 652°C

HF Cb-lzr 5000/816-927 Minor deformation of 109 bellows used for contain• ment attributed to differ• ential thermal expansion.

-162- G. Melting Points and Phase Diagrams One objective of this study is to identify the fluorine containing salts that melt within the various temperature ranges required by TES systems. Decomposition upon melting is not acceptable. The nature of the solid-liquid trans• formation must be completely reversible. Mixtures whose melting point may change greatly because of traces of impuri• ties are not desired. Peritectic mixtures, therefore, were not considered. The data we have chosen to present are of single salts, congruently melting complex salts, and eutectic compositions. If a set of salts has more than one eutectic, we required in general that the melting point of the congruent compound be at least 20° higher than the melting point of either of the eutectic compositions before we considered both eutectics. If the 20° differential did not exist, only the lower melting of the eutectics was selected for further consideration. . The shape of the phase diagram is important. A eutectic mixture whose eutectic is broad will require less accuracy in mixing to obtain the desired melting point than will one with a sharp minimum. If the maximum of a congruently melting compound is broad, the likelihood of the compound falling down the slope of the phase diagram is less than if the maximum is sharp. A congruently melting composition with a sharp maxi• mum probably requires much greater attention to its purity than does one with a broad maximum. Compared with chloride, bromide, and iodide systems, mixtures of fluorides have little tendency to form solid solu• tions. This is attributed to the difficulty cations have in fitting into the fluoride lattice. On the other hand, fluorides are miscible with each other essentially over the entire range of compositional variation.

-163- Mixtures of high cost compounds with low cost compounds were considered to varying degree, depending on the compositic If a high proportion of high cost compound were required, the mixture was not given further consideration unless redeeming features were apparent. Generally, only the lower cost eutectic was chosen of mixtures of high and low cost materials that formed more than one eutectic. Particularly for the more common fluoride compositions, multiple and conflicting melting point data were found. The variability of the data can be attributed to differences in experimental methods and to the extent of purification. We did not critically examine the original literature to determine the "correct" values because highly purified materials have no practical usefulness for real life heat-storage purposes. Melting point data for some of the more interesting com• positions are given in Table XXXV. Because of special interest in aluminum-containing materials, melting points of these compositions are given in Table XXIII. Although these tables may seem extensive, they represent a distillation from data on a much broader variety of materials. A number of phase diagrams of fluoride mixtures are pre• sented in Appendix III. Additional phase diagrams of fluorides can be found in several compilations.117—11 9 ' 123 Examination of the phase diagrams of mixtures of metals and metal fluorides showed the absence of any eutectic points, thereby eliminating this class of materials from further consideration. The mixture of LiF and LiOH has been reported to have many desirable properties for use as a heat storage media.13 4 In the search to find more cost effective materials, we con• sidered the use of other mixtures of metal fluorides and metal hydroxides. However, examination of phase diagram data ruled out this possibility. The mixtures of NaF/NaOH and KF/KOH do not have eutectics. Although MgF2/Mg(OH)2 and CaF2/Ca(OH)2 have eutectic points, these compositions may be unstable,

-164- splitting off water, and resulting in corrosion. The eutectic compositions of MgF2/MgO and CaF2/CaO melt above 1200°C and are out of the temperature range of current interest. Certain mixtures of fluorides - chlorides and fluorides - "carbonates are found to have suitably melting eutectic mixtures and there• fore can be considered as potential heat storage media. Good mixing "and sufficient time for equilibration is required for these mixtures before accurate property measurements or use can occur. Whenever mixed anions are present, an equilibrium reaction occurs. For example:

MgF_ + 2NaCl ^^ MgCl9 + 2NaF

-165- H. Heat Contents Fundamental requirements of any medium used to store thermal energy are that its capacity to store heat is high and that the heat can be transferred at the desired temperatures and within time frames dictated by the application. Because each application has different requirements, enthalpy character• istics must be described broadly, even though in practice only certain portions of a material's capacity can be used. The total heat storage capacity of a material that does not vaporize or change chemically can be expressed as follows: J? T T x i /\m A2 H = n \ Cp xdT + n/AH + n \ Cp 2dT + nAH + n \ CpxdT l t m where: n = moles of material T, = lowest temperature T. = transition temperature T = fusion temperature

T9 = highest temperature Cp , = molar heat capacity of phase I solid

Cp 2 = molar heat capacity of phase II solid , &H. = molar heat of transition *% = molar heat of fusion

-166- 1„ Heat of Fusion Much of the attention metal fluorides have attracted for high temperature heat storage applications has been because their heats of fusion are high. Because the mean intermole- cular distance in the liquid state is greater than in the solid state, the heat of fusion is essentially the work which must be done to overcome the attractive forces between the molecules during the change from crystals to liquid. There• fore, the.heat of fusion is greatest for those substances having the greatest intermolecular attractions in the solid state, such as those having a close packing of small and light elements. It follows that salts.have high heats of fusion whereas molecular crystals held together only by van der Waal's forces have low heats of fusion. It should also be pointed out that bonds are not completely broken during the melting process but merely stretched; therefore the heat of fusion is a function of the shape of the potential energy curve in the neighborhood of the minimum as well as of the bond strength.

For substances whose entropies do not vary widely, there is a rough proportionality between heats of fusion and melting points. For fluoride salts, the melting points of their mixtures are lower than the melting points of the individual components. Furthermore, addition of impurities is expected to lower the melting point of any material. Extrapolation of the melting point-heat fusion correlation indicates that mixtures would have lower heats of fusion than the individual components and that impurities would lower the heat of fusion of any fluoride salt or mixture. Of 23 alkali and alkaline earth fluoride mixtures for which the heat of fusions are reported, the heat density per unit weight falls among the values of the individual components 16 times, and is lower 7 times. All of the heats of fusion data for fluoride compositions that were found in the literature are presented in Table XXVI,

-167- TABLE XXVI. HEATS OF FUSION OF FLUORIDE SALTS (* Refers to salts with reported heats of transition - see Table XXVIII)

Average AHm Density I A Km Molecular MP Density I AHm (liquid) (liquid basis) Salt (mole %) Weight ,.fC) (KCal/Mole)Cal/q)" 25° (q/cc) l(Cal/cc) (q/cc) I (Cal/cc) References 67NaF/33ZrF4* 83.35 630 0.6 7.0 3.70 25.9 250 MoF, 209.95 17.5 1.03 4.9 2.55 12 95 420mm 47.01 552 1.14 24.3 2.0 49 95 78.10 234.6 1.58 20.2 2.37 48 95

WF6 297.92 2.S 1.80 6.0 3.44 21 38 420mm 38.4N8F/56.6LiF/4UF4 43.63 64S 2.4 56 3.08 172 251

AsFj 134.91 8.5 2.49 18.5 2.67 49. 99 AsFg 191.91 - 2.74 14.3 79

NbF5 187.9 77 2.92 15.5 3.293 51 186 52L1F/48KF 41.38 492 2.93 70.8 2.53 179 89 PbF2 245.21 826 2.98 12.2 7.75 94 95

TaF5 275.88 96.8 3.00 10.9 4.74 52 92 50LiP/50NaF 33.97 492 3.2 95.3 2.53 241 251 NaBF4* 109.79 406 3.25 29.6 2.53 75 144

SnF2 156.7 219.5 3.3 21.1 4.57 96 248

LiBF4 93.74 310 3.46 59.8 189 AgF 126.88 435 3.5 27.6 5.85 162 248 48LiF/48KF/4UF4 52.9 560 3.6 68 2.85 194 251

46.5NaF/26KF/27.5UF4 121 530 3.7 31 4.53 140 251 45LiF/55RbF 69.13 470 3.8 55 3.27 180 116/117 S0L1F/50KF 41.97 492 3.9 93 2.53 23S 1.806 168 89,117.96.116 10.9NaF/43.5KF/44.5L1F/1.10F4 44.84 452 3.9 87 2.7 235 251 46.5L1F/11.5NaF/42KF 41.29 454 4.09 99.05 2.53 230 2.39 237 96,250 MoF5 190.95 - 4.20 22.0 38

KBF4* 125.92 570 4.22 33.5 2.50 84 95 CsBF4* 219.71 555 4.58 24.1 144

RbBF4* 172.27 S82 4.68 32.9 144

6 5NaF/l5ZrF4/2 0UF4 110.20 610 4.6 42 4.64 195 195

48RbF/48ZrF4/4UF4 143.13 42S 5.0 35 4.19 147 251

BiF3 266 649 5.16 19.4 5.32 103 252 CsF 151.9 703 5.19 34.2 95

50LiP/50BeP2 33.98 360 5.20 153 2.32 355 1

CdF2 150.51 1100 5.40 35.9 6.64 238 38

HgF2 238.61 645 5.5 23.1 8.95 207 95

CrF2 90.01 1100 5.5 61 4.11 250 38

CsF4 125.01 5.5 44.0 38

MnF2 92.93 856 5.5 59 3.92 23 38

BaF2 175.36 1355 5.63 32.1 4.91 158 4.18 134 87 u 52LiF/35NaF/l3CaFj "38.34 615 5.83 152 2.82 429 2.225 101 50NaF/25ZrF4/25UF4 141.34 610 5.9 42 4.93 207 251 56NaF/3 9ZrF4/5UF4 104.46 530 5.9 57 4.10 234 251 RbF 795 104.48 6.15 58.9 3.56 209 79,99,115 60LiF/40NaF 652 32.16 6.17 192 2.72 522 1.930 371 101.64,96,117

-168- TABLE XXVI. HEATS OF FUSION OF FLUORIDE SALTS (Continued)

(* Refers to salts with reported heats of transition - see Table XXVIII)

1 Average Atto Density AHm 1 Molecular MF Density AHm (liquid) [liquid basisj Salt (mole %) I Weiqht CC) IKCal/Mole )l(Cal/q) 25°(q/cc) (Cal/cc) (q/cc) (Cal/cc) References 53NaF/40ZrF4/7UF4 111.16 540 6.2 56.0 4.19 235 251

S0NaF/46ZrF4 110.51 520 6.3 57 4.09 233 251

50NaF/50ZrF4 104.64 510 6.4 61 3.86 235 117 LiF 25.94 848 6.47 249 2.64 657 1.81 451 95 KF 58.10 858 6.50 112 2.48 278 1.95 218 95

79LiF'21CaF2 36.88 765 6.61 179 2.88 384 2.15 385 96

53.NaF/43ZrF4/4UF4 106.75 520 6.7 63 4.09 258 251

65NaF/23CaF2/12MgF2 52.73 745 7.1 135 2.97 401 2.370 320 101.10 18LiF/82LiOH 24.31 527 6.78 279 1.55 432 1.44 402 8

53.5NaF/40ZrF4/6. 5UF4 109.8 550 6.9 63 4.19 264 101.84.38

ZnF2 103.38 875 7.0 67.7 4.9 332 38

44LiF/12NaF/40KF/4MgF2 42.14 449 7.0 167 2.59 432 (2.160) 361

TiF4 123.9 400 7.0 56.5 2.8 158 38

CaF2 70.08 1418 7.1 90.9 3.81 346 2.53 230 95 40.5NaF/59.5KF 51.53 710 7.22 140 2.51 351 1.936 271 96.116

67NaF/33UF4 131.78 630 7.4 56 251

36.5NaF/63.5ZrF2 80.97 635 7.4 91 4.05 369 118+

46LiF/44NaF/10KgF2 36.64 632 7.51 205 2.81 576 2.105 432 8 101

66.7HaF/33.3CaF2 54.01 810 7.65 141 2.86 403 2.23 314 96

35NaF/50KF/7MgF2 52.76 685 7.65 145 2.85 413 2.090 303 101.138

85.5KF/14.5MgF2 58.7 778 7.79 133 2.56 340 96 NaF 42 996 7.97 190 2.56 486 1.941 369 95

NiF2 96.69 1100 8.00 83 4.63 384 38

CdF2 150.41 1100 8.2 55 6.64 365

66LiF/34KgF2 38.31 741 8.39 219 2.88 630 2.16 473 10)

64.4L1F/5.6KF/30MgF2 38.66 713 8.72 226 2.78 628 46.96

78.2NaF/21.8Na3AlF6 78.61 889 9.09 116 2.64 306 49

77..|NaF/22.6MgF2 46.58 830 9.27 155 2.94 455 2.19 339 8.101

PuF3 299 9.34 99

CaF2 105.57 770 9.4 89 4.85 435 95

70NaF/30FeF2 57.55 680 9.44 164 3.02 495 118+

CrF3 109.01 >1000 9.7 89 3.8 338 38

10MgF2/90BrF2 44.04 675 9.86 224 2.11 473 54.140

Li2BeF4 98.59 472 10.61 108 2.43 262 95

54.3MgF2/45.7CaF2 69.52 944 10.79 155 3.09 479 2.49 386 96

UF4 314.02 932 11.23 35.8 6.7 239 180

SrF2 125.63 1463 11.8 94 4.29 403 3.47 ' 326 83

FeF3 112.85 Sublines 1200 106 3.52 373 38

FeF2 93.85 1102 12.4 132 4.09 539 95

CeF3 197.13 1459 13.2 67 6.16 412 249

MgF2 62.32 1263 13.9 223 3.13 698 2.43 542 95

CoF2 102.97 1127 14.06 145 4.46 647 95

ZrF4 167.29 932 15.35 92 4.54 418 95

NaMgF3 104.32 1030 17.7 170 2.85 484 247

76NaF/12BeF2/12UF4 75.25 514 18.4 244 3.77 920 251

Li-,A1F6« 161.78 785 20.6 127 2.75 349 95

|A1F6« 209.96 1012 25.64 122 2.95 360 2.100 256 95 '1*6 258.27 1000 27.6 107 3.04 325 95 Cs3AlF6 539.69 811 29.9 54 151

K3A1F6 258.27 1000 33.5 130 254

Rb3AlFc 397.38 927 34.5 87 254

-169- along with the corresponding average molecular weights, densi• ties, and melting points. Heats of fusion are usually reported in kcal/mole. Calculation of AHm in terms of energy/unit mass follows directly. However, calculation of energy/unit volume requires knowledge of composition densities. Because density is temperature dependent, the value of AHm/volume depends on temperature. We have chosen to use both ambient densities and densities of the liquid compositions at the melting point. Use of ambient densities allows comparison with other materials and permits calculation of AHm/volume for a greater number,of compositions because of the abundance of density data at this temperature. Calculation of AHm based on liquid densities, on the other hand, accounts for the change in volume experienced by the fluoride salts as their temperatures are increased. The value obtained can be used more realistically to determine container size requirements. Any calculation of total heat content/volume of energy storing material must use the lowest density value that material will have in its ambient to highest operational temperature range before container size determinations can be made. By inspection of Table XXVI, the following salts are found to have heats of fusion greater than 150 cal/g: cal/g cal/g 18LiF/82LiOH 279 NaF 190

LiF 249 79LiF/2lCaF2 179

76NaF/12BeF2/12UF4 244 NaMgF3 170

64.4LiF/5.6KF/30MgF2 226 44LiF/l2NaF/40KF/4MgF2 167

10MgF2/90BeF2 224 70NaF/30FeF2 164

MgF2 223 40NaF/60MgF2 156

66LiF/34MgF2 219 54.3MgF2/45.7CaF2 155

46LiF/44NaF/10MgF2 205 50LiF/50BeF2 153 60LiF/40NaF 192 52LiF/35NaF/13CaF„ 152

All except two (FeF? and UF.) of the components of these highest energy/weight fusion density materials belong to the alkali and alkaline earth groups, in accordance with heat of

-170- fusion theory. Interestingly, many of the high energy/weight mixtures are composed of individual salts that also have high energy/weight. Therefore, additional combinations of these component salts might |be expected also to have high energy/ weight. On the other hand, compositions containing signifi• cant amounts of low energy/weight components cannot be ruled out because there are a number of mixtures containing CaF_

(90.9 cal/g) and BeF2 (24.3 cal/g) that have high energy/weight. The fluoride-containing material with highest energy/weight density is the LiF/LiOH mixture. The AHm is an experimental value and represents the only heat of fusion value we have found for fluoride-non fluoride mixtures. For heat storage applications where the equipment is the cost-driver, the energy stored/volume of material is most important. As found in Table XXVI, the following fluoride compositions all have energy/volume fusion densities greater than 400 cal/cc (based on solid densities). :al/cc cal/cc

76NaF/l2BeF2/l2UF4 920 10MgF2/90BeF2 473

MgF2 698 40NaF/60MgF2 459

LiF 657 CuF2 435

CoF2 647 44LiF/l2NaF/40KF/4MgF2 432

66LiF/34MgF2 630 18LiF/82LiOH 432

64.4LiF/5.6KF/30MgF2 628 52LiF/35NaF/13CaF2 429

46LiF/44NaF/l0MgF2 576 ZrF4 418

FeF2 539 35NaF/58KF/7MgF2 413 60LiF/40NaF 522 CeF3 412 70NaF/30FeF2 495 65NaF/23CaF2/12MgF2 407

NaF 486 SrF2 403

NaMgF3 484

54.3MgF2/45.7CaF2 479 Several points bear attention. The first is that the energy storage effectiveness appears quite different on a volume basis compared to the weight basis. The LiF/LiOH

-171- mixture, for example, instead of ranking first in effectiveness is found to rank 18th. Although the alkali and alkaline ear materials appear still to be of highest general effectiveness, other cations are also important. In fact if more data were available, some of the other metal fluorides would probably rank in the highest energy storage/volume values, to the exclu• sion of some of the alkali and alkaline earths. For example, mixtures containing CoF~ would be expected to rank high because

AHm for CoF2 is very high, but data for them are not available, In order to determine whether or not general trends exist in various groups of fluorides, it is useful to list them as such. The heats of fusion of the alkali and alkaline earth fluorides have been extracted from Table XXVI and are listed in Table XXVII. In general, the energy/weight and energy/vol• ume decrease with increasing cation weight within each of these two groups. This is attributed to decreasing lattice energy with increasing cation size. Exceptions are found in the cases of BeF2 and CaF~ where solid-solid transitions are complicating influences. The question of the ,AHm of BeF„ is academic as far as most heat storage applications are concerned because of the toxicity and cost of BeF~, but this compound's disproportionate contribution to the heat of fusion of its mixtures is noteworthy. Similarly, CaF2 seems to have a larger effect on mixtures than would seem appropriate from its relative position. Of 23 mixtures of alkali and alkaline earth fluorides, the values of the A Hm/weight fall within the values of the AHm/weight of their components 16 times. In 7 cases, the values are lower than all of the individual components.

The mixtures of alkali and alkaline earth fluorides for which no heat of fusion determinations have been reported are:

KF/MgF2 NaF/KF/CaF2

KF/CaF2 KF/MgF2/CaF2

LiF/KF/CaF2 NaF/KF/MgF2?CaF2

LiF/MgF2/CaF2 MF/Non-Fluorides

-172- TABLE XXVII. HEATS OF FUSION OF ALKALI AND ALKALINE EARTH FLUORIDES

kcal/mole cal/g cal/cc

LiF 6.47 249 657

NaF 7.97 190 486 KF 6.50 112 278

RbF 6.15 58.9 209

CsF 5.19 34.2 123

BeF2* 1.14 24.3 49

MgF2 13.90 223 698

CaF2* 7.10 90.9 346

SrF2 11.8 94 403

BaF2 5.63 32.1 158

♦Compounds for which solid­solid transactions occur.

­173­ Although fusions of fluoride salts generally are reported to occur sharply, this is not always (or possibly ever) the case. The fusion of PbF0, for example, was reported to occur 253 over a 100° temperature differential. Differences found in the literature for the heat of fusion of given fluoride salts probably result from differ• ences in purity and experimental procedures. A standard method of measuring heats of fusion is with a 2fifi calorimeter. A calorimeter consists of an inner chamber surrounded by a jacket which is insulated on the outside. For the high temperatures associated with metal fluoride systems, the jacket is made of relatively massive mental. The jacket contains heating elements such that an even distri• bution of heat can be obtained. Samples are placed in the inner chamber of the calorimeter and the temperature is slowly raised through the jacket. After calibration of the calori• meter, the temperature effects caused by the samples can be converted to heats of fusion, transition, etc. A variation of this method is called "drop calorimetry," in which the fluoride, is dropped into the calorimeter, and the resulting heat gain of the system is measured. Differential Thermal Analysis (DTA) has been recently developed into a tool for quantitative measurements. In this method a recording is made of the difference in the temperature between a substance and a reference material as the two specimens are subjected to identical temperature regimes in an environment heated or cooled at a controlled rate. This recording shows exothermic and endothermic transi• tions and the area under these curves is directly propor• tional to the heats of these transformations. This method of measuring AH'S is still quite controversial in that accuracy may not be greater than ± 10% at high temperatures. Great care must be used in interpreting this type of data.

-174- 2. Heats of Transition Solid-solid transformations generally do not occur in fluoride salts. For those materials that do undergo large heats of transition, the heats of fusion are lower than other• wise expected. If the maximum AH is desired at the fusion point, solid-solid transitions are probably not useful. However, if heat storage is desired over a range of tempera• ture, then those mixtures with substantial heats of transition may be particularly applicable. One such candidate is Na-AlF... Its heat content is given in Figure XXV. The heats of transi• tion and the heat of fusion total 450 cal/cc in this case. Other fluorides with solid-solid transformations are given in Table XXVIII. 3. Heat Capacity and Sensible Heat The term "sensible heat" is used to refer to those portions of the heat content that are not associated with solid-solid or solid-liquid transitions. It refers to the first, middle, and last terms of the total heat content equation given on page 156. Sensible heat is the summation of the specific heats over a specified temperature range and can be determined experimentally and expressed as an equation. When these thermodynamic quantities are determined by more than one research group there is often disagreement as to their exact values. For example, the four different sets of heat content equations for NaF which appear in Table XXIX were determined in different laboratories. A number of parameters are responsible for these variations, including sample purity, sample form, and experimental procedure. In order to deter• mine the "true" thermodynamic quantities, most experiments are done on ultrapure materials. On the other hand a salt used for heat storage application would probably be of a practical grade because of the economics of the system. On this basis the thermodynamic va3.ues in the literature can serve only as a guideline for choosing the proper salt system

-175- 110

100 K3A1F6

90

80

/ 70

Li3AlF6 60 - I r-l a u 50

CO o-> CM 8 40 I X

30 -

20 -

10 -

200 400 600 800 1000 1200 1400 Temperature (°K)

Figure XXV. The Enthalpy and Enthalpy of Fusion of Li3AlF6, Na3AlF6 and K2AlFg

-176- Table XXVIII. Heats of Transition of Fluoride Salts

AH, Average Fluoride Molecular Salt Weight TT CO Kcal/mole Cal/g Cal/cc Ref

A1F 83.98 Sub 0.16 1.91 6 97 3 BeF2 47.01 227 0.53 11.3 22.6 45

Li3AlF6 161.78 475 (0.5 3.1 45 575 0.9^0.3 1.9 45 705 (,0.1 0.62 45 CaF, 78.08 1151 1.14 14.6 46 45 PbF, 245.19 452 65 2.65 21 45 340 61 2.49 19 45

NaBF4 109.82 243 1.61 14.7 37 144 67NaF/33ZrF. 83.34 495 6.9 26 117 525 ■L,/L1.1 13.8 51

CsBF4 189.73 170 1.94 10.2 144 Na AlF­ 209.96 565 97 9.4 28 45 03 6 880 Ml: 09 .43 1.3 . 45 81 45 KHF2 78.10 197 2.67 34.22 RbBF^ 142.3 245 2.86 20.1 144 KBF„. 125.92 283 3.36 26.7 67 45 Table XXIX. Thermodynamic Equations For Sodium Fluoride H Phase V :29 8 Temperature Range (eK) Reference

3 2 solid - 9.66T + 2.25 x 10~ T - 3080 298-1265 287

liquid = 16.OT + 280 1265-1300 287

3 2 1 solid - 10.40T + 1.94 x 10" T + 0.33 x loV" - 3384 298-1285 62

liquid - 16.40T + 170 1285-1800 62 CO I 3 2 5 _1 solid 8.412T + 3.115 x 10~ T - 1.963 x 10 T - 2144 298-1285 72

liquid - 16.866T - 89 1285-1800 72

solid 10.79T + 2.38 X 10~3T2 + .862 x 105T_1 - 3718 526-1268 289

liquid 10.91T + 2.33 x 10~3T2 + .938 x 105T_1 + 4226 1268-1576 289 and are not expected to be accurately defined for the actual system. Once a system is chosen, then the thermodynamic quantities for that system should be determined using samples of the purity actually used. For this reason we have not concerned ourselves in this report with what is the "true" thermodynamic value from the literature, but list representa• tive examples as guidelines. Some of the specific heat and heat capacity data that we have found for metal fluorides are presented in Tables XXX and XXXI. This data can''be used to obtain a general idea about the amount of heat that can be stored as sensible heat. We have calculated the AH from room temperature to the melting points and the AH from the melting point to 100° above its melting points and expressed then in terms of kcal/mole, cal/g, and cal/cc. The very wide variation between materials for the lower temperature range results from variations in the melting points of materials and hence the variation in ^T over which the determinations were made. Over the constant interval above the melting points, AH generally falls in the 20-60 cal/g (65-160 cal/cc) range. Graphically, heat contents can be expressed as shown in Figure XXV and Figures XXVI - XXIX. Sudden increases refer to phase transitions.

-179- Table XXX. Specific Heat and Haat Content Function, of Selected Hetal Fluoride. Melting [cal/mole ] t­*C Temperature Fluoride Salt PointCK) Thermodynamic Equation L*=cal/gramJ T"°K Range CK) Reference

LIP 14.07t + 53.5 x 10*5t2 6.28 x 10~7t3 298­11a 290 1121 H'­H" 298 10 4 ♦ 10.45 x 10" t ­ 2801.8 log10 (t «• 273.16/273.16) 14.07 + 10.70 x 10 't ­ 18.85 x 10"7t2 298­1121 290 + 41.78 x 10_10t3 ­ 1216.6/t ♦ 273.16 4076.4 + 15.Sit 1121­1169 290 298 15.51 1121­1169 290

1268 10.79T ♦ 2.38 X 10_3T2 + 86227T­1 ­ 3718 526­1268 289 HaP H*­H' 298 10.79 + 4.76 X 10"3T ­ .86 X 105T~2 526­1268 289 CP 3 2 ­1 H*­H* 10.91T ♦ 2.33 x 10" T + 93836T + 4226 1284­1576 289 298 10.91 ♦ 4.65 x 10_3T + .94 x 10ST~2 1284­1576 289 CP

11.92T + 1.36 x 10"3T2 ♦ 96627T­1 ­ 3997.5 505­1122 289 KF 1131 *298 3 5 2 C 11.92 ♦ 2.72 x 10~ T ­ .97 X 10 T~ 505­1122 289 P 11.85T ♦ 1.38 X lO"3!2 + 91115.7T_1 ♦ 3085 289 H'­H° 298 1122­1482 5 2 C 1122­1482 P 11.85 + 2.76 x 10 .91 X 10 T~ 289

3 2 1 507­1058 289 RbP 1048 H'­H* 298 11.71T + 2.09 x 10" T + 81764T" 3952 5 ­2 C 507­1058 289 P 11.71 + 4.18 x 10"\ ­ .818 x 10 T 4 3 2 ­1 1058­1376 H ­H" 298 11.30T + 2.32 x 10" T + 56891.8T + 2414 289 3 5 ­2 C 1058­1376 289 P 11.30 ♦ 4.64 x 10" T ­ .569 x 10 T

3 2 5 _1 298­1536 291 HgF, 1536 '298 16.93T ♦ 1.26 X 10" T + 2.2 X 10 T ­ 5898 16.93 + 2.52 x 10­3T ­ 2.2 x 105T­2 298­1536 291 1536­1800 291 H*­H» 298 22.57T ♦ 2.450 1536­1800 291 CP 22.57

14.30T ♦ 3.64 x lO­3!2 ­ 4.69 x 105T­1 298­1424 291 a form trans 1424 H°­H" 298 4430 ­3 5 ­2 CP 14.30 + 7.28 x 10 T + 4.69 X 10 T 298­1424 291 3 2 1424­1691 291 0 form melt 1691 H*­)** 298 25.BIT ♦ 1.25 x 10" T 14869 _3 C 1424­1691 291 P 25.81 ♦ 2.5 X 10 T *298 23.88T ­ 930 1691­1800 291 23.88 1691­1800 291

1350 298­1300 287 BaP, 298 13.98T + 5.1 x 10i­V ­ 4621 C„ 13.98 + 10.20 x 10"3T 298­1300 287

_2 2 2 A1F, a form 728 ­6.28(T­T0) + 7.06 x 10 (T ­To ) 273­728 292 ­5 3 3 8 4 transition ­8.26 x 10

I form 1291 H 20.93T ♦ 1.50 x 10 6500 727­1400 62 sublimes V 298 " 20.93 ♦ 3.00 x 10 ­3"T. 727­1400 62

­180­ Table XXX. Specific Heat and Heat Content Functions of Selected Metal Fluorides (Cont'd) Melting fcal/molo 1 t=°C Temperature Fluoride Salt Point CK) Thermodynamic Equation L*=cal/gram.J T^K RanqaCK) Reference

­3 2 5 _1 Ha,AlF6 a form 845 H » 45.95T ♦ 14.73 x 10 T ♦ 2.78 X 10 T 298­845 62 transition V 298 ­ 15942 , = 45.9S + 29.46 x 10_3T ­ 2.76 x 105T­2 298­845 62

1205 Hj­Hjgg ­ 28.06T + 2.2 x 10­3T2 + 4.116 x 105T­1 9942 298­1205 293 3 S ­2 Cp ­ 28.06 + 4.4 x 10~ T ­ 4.116 x 10 T 298­1205 293

Cp » —29 (not accurate) 1205­ 293

1145 C„ ­ 13.6 ♦ 6.71 x 10"3T 298­1145 263

5 2 60LiP/40NaF* 925 H"­H°29e « ­0.1 + 0.319t + 9.94 x 10" t 385­845 117 n-S>. 385­845 117 ­78.5 + 0.925t ­ 24.62 x 10 5."t2 961­1171 117 298 961­1171 117

50LiF/50KF* 380­739 117 765 H°­H» 298 0.282 + 7.64 x 10 't 380­739 117 ­23.8 + 0.S84t ­ 10.28 x 10­5t2 805­1166 117 Ho­H" 298 C„ 0.584 ­ 20.56 x 10­5t 805­1166 117

43LiF/57HbF* 748 K<,­H,>. ­1.1 +,0.18St + 2.45 x 10"5t2 407­693 117 407­693 117

22 9 + 5 2 "'"""JO29B8 " " ­ 0.39't ­ 8.1 x 10" t 770­1151 117 5 C, 0.397 ­ 16.1 x 10" t 770­1151 117

46. 5LiF/ll. 5NaF/42KF» ­35„2 H^­H" 298 ­2.6 ♦ 0.271t + 9.8 x 10 f 333­727 117 333­727 117 748­1148 117 748­1148 117

­5 55LiF/22NaF/23ZrF4« ­5.2 843 H'­H" 298 ­1.5 + 0.239t + 7.2 x 10 t 379­641 117 379­641 117 H'­H" ­13.0 + 0.453t = 5.95 x 10~St2 298 876­1170 117 S 0.453 ­ 11.89 x 10~ t 876­1170 117

20LiF/80HOH* 700 solid 298­700 134 0.39 liquid 700­

­181­ Table XXXI. Heat Contents of Selected Metal Fluorides

Fluoride Salt Melting Hm~H298 Hm+100"Hm Reference Point (°K) Kcal/mole "V?. cal/cc ▼ Kcal/mole cal/q cal/cc *r

LiF 1121 10.4 400 1056 1.5 58 153 298

NaF 1268 13.8 329 842 1.7 40 102 298

KF 1131 11.3 194 481 1.5 26 64 298

RbF 1048 11.0 105 1.6 ' 15 298

MgF2 1536 23.2 372 1164 2.3 37 116 95 I »­• CaF2 a form 1424 23.3 298 948 00 1691 32.6* 418 1329 2.4 31 99 95 to I BaF2 1350 23.7 135 663 287

A1F3 to 1500 28.5 339 95

Na3AlF6 1285 67.9* 323 953 9.5 45 133 95 ZrF. 1205 27.4 164 745 ­2.9 17 77 298 4 60LiF/40NaF 925 8.0 247 672 1.9 59 160 117 50LiF/50KF 765 6.1 145 367 2.0 48 121 117 43LiF/57RbF 748 6.4 92 2.2 32 117 46.5LiF/ll.5NaF/42KF 727 5.8 140 364 1.9 46 120 117

55LiF/22NaF/23ZrF4 843 9.8 233 794 2.4 57 1.94 117 20LiF/80LiOH 700 4.9 202 313 0.9 37 57 134

* Includes AHT, a­»B £ p=.ao/^ on ambient densities " 1 1 1

1 CaF2

2 MgF2 -// 1

36,000 ­

« 27,000 o a V VO H

CO

CM 1 K 18,000 y2 X

9,000 ­

■ • • 1 200 600 1000 1400 1800 Temperature (°K)

Figure XXVI. Heat Contents Above 298.16°K

­183­ Figure XXVII. Enthalpy Curve, H" ­ H|98 j_ in kcal/mole for NaMgF,

0) —r—r— ­T 1 "1 1" » r4 ­1—­r­ o ^ 50.0 n V X AHf = 17.70 ID . ■ ­ kcal/mole' en 40.0 * • ­ OCx M 1 _ , oh X 30.0 «

­1 L— —I t__ __». _.». _l 1 1 1 1— 1250 1300 Temperature (°K)

T~" —i— ""T~ i —r—I—­r — ­l r­""i —i— I i ~T" —T~ —r­"T"

25 ­

R) 8.70 kcal/mole O AHf = 20 ­ ­

CO 0> ocs X 15 • oh X

10 _1_ _L _i_ 1 i —J l, ­J 1 1 1— _i_ L_ ._l— i­ __L_ _l_ 1000 1100 1200 1300 Temperature (°K)

Figure XXVIII. Enthalpy Curve, H°, ­ H°,98<15, in kcal/mole,

for (0.782NaF + 0.218MgF2)

­184­ /»

Figure XXIX. Enthalpy Increments HT - H2g8 15 and Enthalpy of Fusion of the Eutectic Mixture 21.8 mole %

Na3AlF6 + 78.2 mole % NaF at 1162°K

4 10 u

oo CM X I X

1050 1100 1150 1200 1250 1300 Temperature (°K)

-185- I. Volume Changes and Density The energy density/volume is a parameter of prime impor• tance for the storage of heat in metal fluorides or any other material. The volume required to store the required amount of energy has direct bearing on the size of the storage con• tainer, the amount of insulation required, the amount of space required, and the design and complexity of the heat transfer equipment. As a consequence, the energy density/ volume is an important cost determinant. A distinguishing feature of metal fluoride-s is that their energy densities/volume are higher than any other practical latent heat of fusion storage materials. Those fluoride salts with both high energy density and specific density are optimum for reduction of container size. However, total volume cannot be calculated directly from weight and ambient density data because of the expansion of metal fluorides with increasing temperature and upon melting. When cooled, they contract by a similar amount. This common phenomenon must be accounted for during system design. The volume of the container must be at least as large as the salt will expand to at the highest service temperature. To determine this volume, the density at that temperature must be known. If the container is not designed with enough room for expansion, or if local pressures are allowed to build up, equipment failure may occur. Changes in volume of metal fluoride salts are presented in Table XXXII. For those cases where sufficient data are available, the changes in volume from ambient temperature to the melting point are found to be smaller than those experi• enced upon melting. The change upon melting, where known, ranges from 14-30%, whereas the total volume change ranges from 7.6-45.9%. (The LiF/LiOH mixture undergoes the lowest total volume change and LiF/NaF/KF has the second lowest.) The largest total volume change is that of LiF, a material that has been successfully cycled through the melting point many times in experimental heat storage systems. This indi-

-186- TABLE XXXII. DENSITIES (g/cm3) AND VOLUKE CHANGES OF FLUORIDE SALTS

% A * A* A Composition (Mole %) HPl'C) D25°C DMP(Solid) DMP(Llould) Reference Av25°­MP AyMP ^VTotal LiF 848 2.64 1.81 99,97 45.9

NaF 996 2.56 1.941 116t96 31.9

KF 858 2.48 1.95 96 27.2

75KF/25A1F3(congr.) 985 1.828 116

15A1F3/85L1F 719 2.037 116

35A1F3/65L1F 716 2.041 116 lS.2AlF3/B4.8NaF 910 2.078 116

Na3AlF6 1006 2.95 2 62 2.100 116.97 12 6 24 8 40.5

50H«F/50BaF2 895 3.598 116

80LiF'20CaF2 769 2.053 116

33.1CaF2/66.9LiF 810 2.299 116 50KF/50L1F 490 2.53 1.806 116 40.1

60KF/40NaF 710 2.51 1.938 116 29. 5

33.3ZrF4/66.7KF 800 2.220 116

40KaF/60LiF 6S2 1.9052 116

8NaF/92NaBF4 384 1.963 116

75NaF/252rF4 850 2.43 116

58KF/35NaF/7MgP2 685 2.090 261

52LiF/3SNaP>13CaF2 615 2.82 (2 63) 2.225 261 7 2 18 2 26.7

65NaF/23CaF2/12MgFj 745 2.97 2 77 2.370 261 7 2 16 9 25.3

66LlF/33MgF2 746 2.88 (2.63) 2.305 261 9 5 14 1 24.9

75NaF/25MgF2 832 2.94 2. 69 2.190 261 9. 3 22. 8 34.2

62.5NaF/22.5MgF2/15KF 809 2.85 2 65 2.110 261 7 5 25 6 35.1

46LiF/44NaF/10MgF2 632 2.81 2 61 2.105 261 7 7 24. 0 33.5

60L1F/40NBF 652 2.72 2 50 1.930 261 8. 8 29. 5 40.9

12NaF/40KF/44LiP/4MgF2 449 ­ (2.160) 261

MgF2 1263 3.13 2.43 97; 96 28.8

CaF2 1418 3.18 2.53 96(99 25.7

8rF2 1463 4.29 3.47 139t99 23.6

BaF2 135S 4.91 4.18 97199 17.5

F«P3 sublimes 3.18 112

MnF2 856 3.92 112

CuF2 770 4.85 112

ZnF2 875 4.90 97

SnP2 219.5 ,, 4.57 79

PbF2 826 7.75 80 txr4 932 4.54 112

45. SNaF/S4. 5Na3AlF6 2.098 99

12.4CaFj/87.6Na3AlF6 Ca 995 2.129 99

1. At 847° 2. At 857* 3. AvT^Av25°­KP ♦AVMP

­187­ TABLE XXXII. DENSITIES (g/cre ) AND VOLUME CHANGES OP FLUORIDE SALTS *VH P I Composition (Hole %) HP CO I DZS'C I DMP(Solld) I DHP(Llguld) 1I Referenc e I £*V25 -HP! A IV Tc 32.2CaF2/67.8Na3AlF6 Ca 970 2.190 99 18LiF/82LiOH 527 1.55 1.44 6 7.6

KBP4 570 2.5 97

NaBF4 406 2.53" 97 60L1F/40KF • 652 2.53 2.06 96 22.8 46.5L1F/11. 5NaF/42KF 454 2.6 2.39 117 8.8 50L1F/50KF 492 2.60 1.89 96 37.6

77.4NaF/22.6MgF2 830 2.69 2.09 96 28.7 41 31.5 66LiF/34MgF2 * 7 2.84 2.16 96

66.7NaF/33.3CaF2 810 2.86 2.23 96 28.3

40NaF/60MgP2 830 2.86 -2.24 96 27.7

79LiP/21CaF2 765 2.88 2.15 96 34.0

NaF/38LiF/ZrF4 605 3.08 2.48 117 24.2

54.3MgF2/45.7CaF2 944 3.09 2.49 96 24.1

NaF/55LiF/ZrF4 570 3.41 2.76 23.6

5NaP/KF/ZrF4 425 3.57 3.02 18.2

NaF/40.5LiF/ZrF4 510 3.74 3.08 21.4

36NaF/KF/ZrF4 450 3.80 3.20 18.8

57NaP/43/ZrF4 • 500 3.86 3.21 20.2

-188- cates that.stresses on equipment because of expansion and contraction can be managed. The thermal expansion of magnesium fluoride has been 175 studied in some detail. The coefficient of thermal expan• sion normal to crystal layers was found to be only slightly greater than that along the layers, whereas for most layered compounds the difference in directions is great. In the case of magnesium fluoride, and probably other fluorides as well, the Coulombic forces between layers are strong, creating resistance to separation of the atoms, AS a result, expansion is uniform in all directions. Calculations of volumetric changes of mixtures based on known values for single salts is risky. In some cases the correlation is good, but in others there is not a direct function to the additive combination of the components.' - Particularly for mixed anion compositions, double decomposition process preclude additivity predictions.,

-189- J. Viscosity . • Viscosities of some of the molten fluorides have been determined and are presented in Table XXXIII. in general, the fluorides are highly fluid, with viscosities on the order of 1.7 - 15 centipoise at the melting point and decreasing as temperature is increased.. This corresponds approximately .to the viscosity of water at room temperature. A notable

exception is BeF9, whose viscosity at the melting point 6 is about 10 poise. The viscosity of mixtures containing

BeF2 decreases rapidly as the proportion of BeF2 is lowered.' The combination of viscosity, surface tension, and wetting behavior of molten fluorides is such that they tend to flow and creep quite readily. This causes problems in experimental measurements because it requires the use of closed containers. For thermal storage applications, this is advantageous because it insures good contact with the container walls, even if the container is not full, thus resulting in good thermal transfer.

-190- Table XXXIII. Viscosity of Fluoride Salts

Viscosity Fluoride Salt T°C Centipoise Ref

60 LiF/40 NaF 652 m.p. 3.77 117 50 LiF/50 KF 600 4.75 117 43 LiF/57 RbF 475 m.p. 10.98 117 600 4.46 69 LiF/31 BeF 505 m.p. 12.34 117 600 7.48

50 LiF/50 BeF2 350 m.p. 376.7 117 600 22.2

70 NaF/30 BeF2 590 m.p. 5.2 117 600 5.0

57 NaF/43 BeF2 360 m.p. 114 117 600 12.6 50 NaF/50 BeF 380 m.p. 106 117 600 15.5

79 KF/21 BeF2 730 m.p. 2.96 117

50 KF/50 BeF2 445 m.p. 84.4 117 600 15.4

50 RbF/50 BeF2 440 m.p. 6.36 117 600 1.1 57 NaF/43 ZrF 600 7.5 117

48 NaF/52 ZrF4 600 8.5 117

90 LiF/10 BeF2 900 3.16 117 LiF 900 1.67 117 46.5 LiF/11.5 NaF/42 KF 454 m.p. 12.4 117 600 4.7

55 LiF/22 NaF/23 ZrF4 570 m.p. 14.3 117 600 11.9 40.5 LiF/22 NaF/37.5 ZrF^ 600 9.4 117

5NaF/52 KF/43 ZrF4 425 m.p. 15.1 117 600 6.1 36 NaF/18 KF/46 ZrF. 600 7.2 117

36 LiF/49 NaF/15 BeF2 597 m.p. 5.5 117

16 LiF/56 NaF/28 BeF2 478 m.p. 11.4 117 600 6.1

35 LiF/27 NaF/38 BeF0 338 m.p. 78.5 117 600 7.7

-191- Table XXXIII. Viscosity of Fluoride Salts (Cont'd)

Viscosity Fluoride Salt T°C Centipoise Ref 49 NaF/15 KF/36 BeF- 555 m.p. 10.2 117 Z 600 8.0 50 NaF/48 ZrF./2 UF. 600 8.5 117 46 NaF/50 ZrFV4 UF. 600 8.9 117 8.5 117 50 NaF/25 ZrF4/25 UF4 600 10.25 117 64.5 NaF/6.0 ZrF4/29.5 UF4 600 11.9 117 66.7 NaF/33.3 UF4 665 m.p. 1.16 x 105 265 BeF2 807.7 6.7 97 Na,AlFc 1009 m.p.

-192- K. Thermal Conductivity In determination of the suitability of materials for heat storage applications, their ability to conduct heat is important. The greater the conductivity of the material, the more efficient is the heat transfer. Complexity and cost of heat exchange equipment is inversely proportional to thermal conductivity of the thermal storage media. Thermal conductivity is the quantity of heat that is trans• mitted per unit time per unit cross section per unit temperature per unit thickness. Generally, solids are better conductors than liquids, and these in turn are better conductors than gases. The mechanism of thermal conduction is quite complicated and has been the subject of much study. In solids, it is accepted that heat is conducted by electrons, magnetic excitations, lattice waves, and electromagnetic radiation. Good electrical conductors always are also good thermal conductors. For crystalline materials, high conductivities are correlated with simple, as opposed to complex, crystal lattice structures and to high Debye temperatures. Metal fluorides have advan• tages in these properties compared to metal carbonates, oxides, chlorides, and others.

In liquids, thermal transfer is accomplished by means of convection and conduction, as well as radiation. These mechanisms sometimes are sufficient to offset the loss in conductivity in going from the solid form to liquid form. More often, loss of the lattice-controlled pathways results in reduced conductivity. This is true for metal fluorides as well as other materials. The thermal conductivities of a variety of metal fluorides have been determined both at low and high temperatures and some of the results are given in Table XXXIV. Those studies that were done at higher temperatures were concerned with heat transfer, especially in nuclear fuels. In general, the molten fluorides are good heat transfer media compared

-193- Table XXXIV. Thermal.Conductivity of Fluoride Salts

Fluoride BTU/hr Cal/sec Salt T°C State Ft °F cm °C Reference mole %

LiF 250 s 4 .016 272 450-650 s 3 .012 272 860-1200 1 1 .004 272 499 s 2.8 .014 96 CaF, 75 s 3.6 .015 139 175 s 2.4 .010 139 775 s 1.2 .005 139 BaF. 25 s 6.3 .026 139 100 s 6.0 .025 139 NaF - KF - LiF s 2.7 .011 273, 117, 277 VO 11.5 42.0 46.5 454 2.6 .011 273, 279, 117, 276, 277 4s. 1 i NaF - KF - UF4 1 0.5 .002 273, 117, 277 46.5 26.0 27.5 NaF - KF - LiF - UF4 452 1 2.3 .009 273, 279, 117, 277 10.9 43.5 44.5 1.1 s 2.0 .008 274, 277, 273, 117 NaF - ZrF4 - UF4 s 0.6 .002 273 46 50 4

NaF - ZrF4 - UF4 540 1 1.2 .005 273, 279, 117, 277 53.5 40.0 6.5

NaF - ZrF4 - UF4 520 s 0.5 .002 273, 117, 277 50 46 4 1 1.3 .005 273, 279, 117, 274, 277 NaF - BeFo 360 1 2.4 .010 273, 279, 275, 277 57 43

RbF - ZrF4 - UF4 425 1 1.0 .004 273, 279, 117, 48 48 4 Table XXXIV. Thermal Conductivity of Fluoride Salts (Cont'd)

Fluoride BTU/hr Cal/sec J™* % ^£ State Ft °F cm °C Reference

^oF ' 5S " ^4 500 s 1.4 .006 273 48 48 4 43F " Ti*4 4?5 1 1'2 -005 273> 279> H7

onF " oi°H 13° s 3-° -012 20 80 M P 430 s 1.8 .007 134 9 o2 325 s 3.5 .014 278 550 s 2.9 .012 r- 900 s 2.3 .009 VO en I to many other substances. The metal fluoride thermal conducti- 2 vities range from 0.002 - 0.01 cal/cm -sec (°C/cm), or 0.5 - 2 2.6 Btu/ft -hr (°F/ft) near the melting points. At lower temperatures, the-values are somewhat higher. .For comparison, 2 the conductivity [in cal/cm -sec(°C/cm)] of Inconel metal is 0.036 (RT), Hastaloy B is 0.027 (RT), water 0.00143 (RT), maple wood is 0.0045 (RT), Pyrex glass is 0.0030 (100°C), magnesia brick is 0.0072 (1130°C), solid NaCl is 0.0038 (801°C), and liquid NaOH is 0,0022 (319°C). The variation of thermal conductivity of molten fluorides with temperature is relatively small, but variations in the solid range can be several fold. For example, Figure XXX shows the temperature dependence of thermal conductivity for lithium fluoride. r The thermal conductivity of fluoride salts has been shown to be sensitive to the influence of impurities. As illustrated in Figure XXXI, conductivity drops with increasing impurities such as those formed by corrosion. This indicates that de• creased thermal transfer performance would result from corro• sion, probably long before mechanical failure would occur.

-196- !

8 . e fa o . . u < 6 — - m o *? 5 - > I •H •U 4 -. e _ M O VD o I C O - « o o o° U 3 - -

2 -

1 - 1- - i *®na0 a^aa. L_ f 1 U 1 . 200 400 600 800 1000 1200 1400 Temperature (°C) Figure XXX. Lithium Fluoride Thermal Conductivity 272 Variation with Temperature Figure XXXI. 0.056

Effect of Impurities on the Thermal Conductivity of FLINAK 191 (11.5NaF/42KF/46.5LiF) 0.052

0.048

0.044

0.040

\ JJ 0.036 it)

0.032

0.028

Impurities: 3 > 2 "» 1 0.024

0.020 I I J. Ju ■J. 300 400 500 600 700 800 900 Temperature (eC)

­198­ L. Supercooling The kinetics of crystallization are often cited as critical problems in heat of fusion thermal storage technology. Many materials tend to supercool, remain in the liquid state below fusion temperature until unpredictable events precipitate sudden crystallization and heat release. Metal fluoride salts apparently do not have this problem. The only reports of supercooling found in the literature refer 120 to an impure sample of MgF0 and pressurized samples of KF 119 and RbF. Reports of work on metal fluorides performed at Oak Ridge and Philips Laboratories state that supercooling is not evident. Interestingly, even in the study that cited supercooling of MgF»,12 0 mixtures containing MgF„ were not observed to supercool.

-199- M. Selected Fluoride Compositions An elimination process for narrowing the number of materials to be considered for further evaluation and use is illustrated in Figure XXXII. The steps shown in the figure are not completely sequential but they serve to systematize the evaluation process. In fact, much of the data for individual metal fluoride compositions is lacking, so a number of generali• zations, assumptions, and predictions were required in order to make selections. A number of compositions were rejected as discussed in previous sections. Others have not merited men• tioning, such as materials _ whose heats of fusion are known to be less than 50 cal/g. In Table XXXV are listed some metal fluoride compositions for which some physical properties have been reported. The list does not include unreported but theoretically interesting compositions. Many of the compositions have one or more known or potential problems, such as high cost, high corrosion potential, hygroscopicity, etc., but are included because of other properties, such as high heat of fusion, or because too little information exists to either reject or adopt them. The fluorides in Table XXXV are arranged according to the temperature range in which fusion occurs. Costs are also given in the table. These costs were calculated based par• tially on the predicted large scale manufacturing costs of individual metal fluorides previously discussed and presented in Table XIX. Selling prices of non-fluorides were obtained from the Chemical Marketing Reporter, November, 1976. Special handling and transportation charges were not included, and a 4C"o rate of return was provided. One material from each temperature increment in Table XXXV that is judged to be the most generally attractive is listed again in Table XXXVI. This second list of selected fluoride materials represents the culmination of our selection process. However, it is emphasized that both tables must be considered when selecting a fluoride salt for a particular application.

-200- Figure XXXII. Metal Fluoride Selection Process

Metal Prices ^ Reject Most Costly

Toxicity ■> Reject Most Toxic —T~ Stability ­> Reject Those Which Decompose

.XL Volatility Reject Those With High ■> Vapor Pressure t- Heat of Fusion ­> Reject Those With LowAHf ± Availability Reject Rare Materials ">

Reject Inappropriate Phase Diagrams ■> Melting Materials

>' Reject Those With High Corrosivity ­> Corrosion Rates L Thermal Conductivity Reject Poor Conductors ■>

V­ Spacific Heat Reject Low Specific ­> Heat Material (For certain applications) >/ Volume Change Reject Materials With "> High % Change X. L Specific Application Reject Those With Requirements ­> Non­Applicable Parameters

JL MF Price ­» Reject High Cost Materials ESELECTE D MATERIAL ­201­ TABLE XXXV. MELTING POINTS OP SELECTED METAL FLUORIDE SALTS

Temperature Type Melting Range Composition Conpoaition (e -eutectic) Point Coot* CO (Mole %) (Wt. %) (c -congruent) •C Reference $/lb. SnP2 SnP, 213 79, 80 $9.49 215 39 219.5 97, 119 42NaF/58SnP, 16.3NaP/83.7SnP- a 228 118 7.95 200-250 KHF2 XHP2 239 95 0.45 NaSnF? NaSnF3 c 240 118 7.50 92NaP/8SnF2 7S.5NaP/24.5SnP2 a 240 118 2.38

255 118 3.68 Na6SnFg Na6snFn 250-300 58KF/42SnF2 280 118 6.36 33.9KF/66.1SnF2 59.7Na3AlF6/40.3A1C13 300 114 0.29 70Na3AlP6/30AlCl3

77KF/23SnP2 55.4KF/44.6SnP2 310 118 4.38 300-350 94KF/6SnF2 85.3KFA4.7SnP2 320 118 1.63

48LiF/52FeP3 17.5LiF/82.5FeF3 360 99 48.4NaP/3.5KF/4B.lBP3 37.0NaP/3.7KF/59.3BF3 377 118 0.88 8NaP/92NaBF4 3.2NaF/96.8NaBF4 380 57 0.39 350-400 10NaF/48KF/42ZrF4 4.1NaF/27.3KF/68.6ZrF4 385 118 1.72 58KF/42ZrF4 32.4KF/67.6ZrF4 390 118 1.70 55KP/5AlF3/40ZrP4 31.0KP/4.1AlF3/64.9ZrF4 400 118 1.64

12KP/88KBF4 5.9KP/94.1KBP4 410 116, 118 0.37 45ZrF4/55NaCl 70.1ZrP4/29.9NaCl 415 119 1.68 20LiP/80LiOH 21.3LiF/78.7Li0H 427 119, 43, 6 2.10 5NaP/S2KP/43ZrF4 2.0NaF/29KF/69ZrF4 425 117 1.71 37NaF/26LiF/37ZrF4 18.5NaP/8LiF/73.5ZrP4 436 118 1.90 44.9LiF/ll.lNaF/43.5KF/- 2 5.3L1F/10.1NaF/51.2KP/- 3.5BaF2 13.3BaF2 438 119 0.58 401-450 45KF/55ZrP4 22.1KF/77.9ZrP4 440 116 1.92 45.6LiF/llT7NaF/41.2KF/- 28.3L1P/11.7Ha?/57.2KP/- 1.5CaF2 2.0CaP2 444 119 0.62 24NaF/30.5LiF/45.5ZrF4 10.7NaF/8.4L1F/80.9ZrF4 446 118 2.08 44LlF/12NaF/40KF/4MgF2 27.1LiF/11.9NaF/55.1KF/- 5.9MgP2 449 127 0.60 80.8Li2TiF6/16.9K2TiP6/- 2.3Ma2TiP6 450 118 0.69

36NaF/l8KP/46ZrP4 14.8NaPA0.2KP/75ZrP4 450 117 1.83

45. 3L1FA1. 2NaF/41.4KF/- 27. 2L1F/10. 9NaP/55.8KP/- 2.1SrF, 6.1SrF2 a 446 119 62 46.SLiP/11.5N8F/42KF 29.2LiP/11.7NaF/59.lKP e 454 96 64 f 25. 5KF/74. 5KBF4 13.6KF/86.4KBP4 e 460 118 36 29NaF/4 2Li F/2 9ZrF4 17NaF/15.2LiF/67.8ZrF4 e 460 88 451-475 58KP/42PbF, 24.7KF/75.3PbF2 a 465 lie 49LiF/46KF/5BaF2 472 118 26.4LiF/55.4KF/18.2BaF2 e 118 62 14CaF2/70LiCl/16NaCl 21.9CaF2/59.4LiCl/18.7MaCl e 474 89 KZrFt 475 119 KZrPj c 118 1.84

18.5CaF2/81.5CaCl2 13.8CaF?/86.2CaCl2 480 119 0.01 SOLiF/50KF 30.9L1P/69.1KF 484 89 0.69 490 116 492 61 20LiF/80LiCl 13.3LiF/86.7LiCl 485 30 49 476-500 25NaP/75NaP03 12.lHaF/87.9NaP03 490 119 23 5LiF/50KF/45AlF3 1.9L1F/42.6KF/55.5A1F3 490 118 21 63KF/15AlF3/22ZrF4 42. 5KPA4. 7AlP3/42. 8ZrF4 490 118 15 59. 5NaF/40. 5ZrF4 27NaF/73ZrF4 500 118 76

79LiF/21ZrP4 36.9LiF/63.1ZrF4 a 507 30 2.11 50NaF/50ZrP4 20.lNaF/79.9ZrF4 a 510 117 1.92 501-525 22NaF/40. 5LJ.F/37. 5ZrF4 11.2NaF/12.7LiF/76.1ZrF4 • 510 117 2.03 25NaF/13KCl/62K2C03 9.9NaF/9.2KC1/80.9K2C0, a 520 119 0.11 34NaF/66PbF2 8.lNaF/91.9PbF2 e 520 118

34KF/35KC1/35K2C03 21.CKF/27.7KC1/51.3K2C03 528 119 0.12 12HaF/34KCl/54Na2C03 5.8NaF/28.9KCl/65.3Na2C03 538 119 0.01 526-550 59.3NaF/40.7PbF2 20NaF/80PbF2 540 4 54CuF2/46PbFj 32.7CuF2/67.3PbF2 550 119

-202- TABLE XXXV. MELTING POINTS OF SELECTED METAL FLUORIDE SALTS (Continued) >rature •iype Melting Composition Composition (e«=eutectic) Point Cost* <°C) (Mole «Q (wt. %) (c»congruent) •C Re fcrenco 5!>KF/45AlF., 4 5.BKF/54.2A1F, 560 118 0.18 18LiF/l7NaF/6 5AlF3 7L1F/10.8NaF/82. 2AIF3 565 118 0.21 23AlF3/77PbF2 9. 3AlF3/90. 7PbF, 570 119 KBF4 KBF4 570 95 551-575 70.5LiF/29.5ZrF4 27LiF/73ZrF4 570 118 2.18 22NaF/55LiF/23ZrF4 14.9NaF/23LiF/G2.1ZrF4 570 117 1.07 14Na2C03/38NaCl/48NaF 25.9Na2C03/38.8UaCl/33. 3NaF 575 119 0.04 70LiF/3OZrF4 26.6LiF/73.4ZrF4 575 120 2.19

51.4LiF/38NaF/10.6AIF3 34.9LiF/41.8HaF/23.3AlF3 580 118 0.62 66.9LiF/33.1ZrF4 23.9LJ.F/76.1ZrF. 590 120 2.21 50LiF/40S'aF/10KCl 34. 9L1F/45.lNaF/20.0KC1 590 119 0.60 576-600 46KF/54KC1 39.9KF/60.1KC1 600 119 0.12 40LiF/17NaF/43AlF3 19. 3L1F/13. 3KaF/67.4AlF3 600 118 0.40 16.5MgF2/03.5MgCl2 11.5MgF2/88. 5MgCl2 596 0.07

65.8LiF/34.2ZrF4 23.0LiF/77ZrF4 603 120 2.21 24LiF/76LiC03 10. 9LiF/89.lLi2C03 604 119 0.87 5lNaF/38LiF/llZrF4 43. lNaF/19.8I.1F/37. lZrF4 COS 117 1.24 55NaF/45NaP03 33. 5NaF/66. 5NaP03 614 119 0.19 63.2LiF/36.82nF2 30.2LiF/70ZnF2 615 16 0.83 52LiF/35NaF/13CaF2 35. 2L1F/38.3NaF/26.SCaFj 615 105,101,127 0.61 27.5BaF2/72.5CuF2 39.6BaF2/60.4CuF2 616 119 0.69 601-625 22.5SrF2/77.5CuF, 26.3StF2/73.7CuF2 616 110 1.08 CuPb2F6 CuPb2F6 618 119 28FeF,772PbF2 13FeF2/87PbF2 620 119 5lLiF736NaF/l3BaF2 25.9L1F/29.6NaF/44. 5BaF2 621 118 0.53 5lLiF/33NiiF/16SrF2 28LiF/29.4NaF/42.6SrF2 624 118 0.62 Na2P03F Na,P03F 625 39 60LiF740HaF 48flLIF/51.9NaF 625 117 0.82 44NaF/56B203 32.2NaF/67.6B203 625 0.10

4 7Li F/4 3NaF/l0MgF2 33.4LiF/49.5NaF/17.lMgF2 630, 105,118,127 0.59 632 26NaF/6 3KCl/9BaF2 14.8NaF/63.8KC1/21.4BaF2 632 119 0.07 NajPOjF Na2P03F 635 119,131 67NaF/33ZnF2 45.2NaF/54.8ZnF2 635 118 0.29 20KF/80KPO3 11KF/89KP03 638 119,131,21 626-650 3D.7NaF/61.3Na2C03 20NaF/60Na CO 640 123 0.03 29K TiF /7lKCl 2 3 2 G 57K-)TiK6/43KCl 640 123 0.21 60LlF/20KF/20AlF3 35.4L1F/26.4KF/38.2A1F3 640 118 0.69 30CaF2/70CaCl2 0.03 23.2CaF2/76.8CaCl2 645, 119 650 36LiF/39MgF?/25Srr2 14.4LiF/37.4MgF2/48. 2SrF2 646 118 0.44 40LiF/47NaCI/3CaF2 25.8L1F/68.4NaCI/5.8CaF2 650 119 0.43 6lLiF/39NaF 49.1L1F/50.9NaF 649, 41,119 0.63 652

60LiF/40NaF 48.lLiF/51.9NaF e 652 116,101, 0.82 117,116 35LiF/35MgF2/30BaF2 10.9LiF/26.1MgF2/63BaF2 e 654 118 0. 34 62LiF/38ZrF4 20.2LiF/79.8ZrF4 C 660 16,120 2.23 3lNaF/40KF/29SrF2 17.9NaF/32KF/50.1SrF2 e 664 118 0.27 651-675 79KF/21ZnF2 67.9KF/32.1ZnF2 e 670 118 0.34 675 39,97 0.24 32.3Na3AlF6/9.0AlF3/- 56Na3AlF6/6.2AIF3/37.8CaF2 e 58.7CaF2

47LiF/35MgF,/18CaF2 25.4LiF/4 5.4MgF2/29.2CaF2 676 118 0.48 35NaF/65NaCI 27.9KaF/72.1NaCI 680 119,123 0.03 40NaF/60Na2CO, 20.9NaF/79.lNa2C03 600 119 0.03 40LiF/60NaCl 22.8LlF/77.2NaCl 680 119 0.36 62KF/38K2C03 40. 7WF/59. 3K2C03 680 119 0.18 75KF/25FeF3 60. 7KF/39. 3FeF3 680 22 53NaF/14CaF,/33BaF2 24.4NaF/12.0CaF2/63.6BaF2 680 118 0.16 70NaF/30FeF 51.1NaF/48.9FeF2 681 118 676-700 2 32.3Na3AlF6/9. OAIF3/- 56Na3AlF6/6.2AlF3/37.8CaF2 682 42,97 0.17 58.7CaF2 8OKF/2OKPO3 66.3KF/33.7KP03 684 119 59LiFA2NaF/29MgF 39.8LiF/l3. lNaF/47.lMgF2 664, 116,16 0.71 2 666 46KF/54K2C03 26.4KF/73.6K,C03 e 685 119 0.16 35NaF/58KF/7MgF2 27. 9NaF/63. 9RF/8. 2MgF2 e 685 127 0.20 53.4NaF/46.6AlF3 36.5NaF/63. 5AlF3 e 685 114 0.10 3lNaF/69ZnF2 15.4NaF/84.6ZnF2 a 685 118 0.42 5LiF/40KCl/55BaCl2 0. 9L1F/20.5KCl/78.6BaCl2 a 689 119 0.18 22LiF/76KCl/2BaF2 8. 7L1F/86.0KC1/5.3BaF2 e 690 119 0.17 75LiF/25FeF3 40.8LiF/59.2FeF3 c 690 22 ti3FeF6 Li3FeF6 c 690 132

-203- TABLE XXXV. MELTING POINTS OF SELECTED METAL FLUORIDE SALTS (Continued) Temperature Type Melting Range Composition Composition (e=eutectic) Point Cost CC) (Mole %) (Wt. %) (ccongruent) "C Reference $/lb.

676-700 66NaF/34MnF-> 46.7NaF/53.3HnF2 e 692 116 (Cont'd) 37.5Na3AlFG/62.5AlF3 60Na3AlF,/40Mr3 a 694 20 20 34NaF/58KFA';ZrF4 23. 3Nar/>'..9KF/21.8ZiP4 a 695 lie 69 62NaF/l2. 5CaF2/25. 5SrF2 38.4NaFA4.4CaFj/47.2SrF2 e 699 118 19 , 62KF/12. 5CaF2/25. 5SrF2 46.3KF/12. 5Cat 2/41.2SrF2 a 699 lie 27 40NaF/60KF 32. 5NaF/67.5KF a ca 700 21 115,116 30.2NaF/3. 9Na3AlF6/- 21.4NaF/l3.8Na3AlF6/- 65.9KF 64.8KF e 694 0.23 119

64.4Li?/5.6KF/30MgF2 43.2LiF/8.4KF/48.4MgF2 • 703, 16,96,46 0.78 713 85LiFA5AlF3 63.6LiF/36.4AlF3 e 706 118,16,141, 1.07 120 20LiF/78KCl/2CaF2 8LiF/89.6KCl/2.4CaF2 a 708 119 0.15 40. 5NaF/59. 5KF 32.9HaF/67.lKF a 710 96,116 0.20 3lK?TiF,/69KF 65K2TiFG/35KF O 710 123 0.32 32.lNft3AlF6/C7.9Li3AlF6 38Na3AlFfi/S2Li3AlF6 e 710 97 0.62 50. 5I.1F/25. SCaF2/24BaF2 10.5I,iFA5.9CaF2/73.6BaP? e 710 116 0.33 701-725 6lNaFA9KF/20ZrF4 36.6NaF/15.7KF/47.7ZrF4 ' e 710 118 1.21 20Li F/60KC1 8.0L1F/92.0KC1 a, 715 119 0.15 6SriF/35AlF3 36.5LiF/63.5AlF3 e 716, 116 0.66 718 4 5NaF/38KFA 7Zr F4 27.2NaF/31.8KF/41ZrF4 e 720 116 1.08 40HaF/G0KF 32.5NaF/67. 5KF e 721 118,119 0.21 53LiF/21SrF2/26BaF2 16LiF/30.8SrF2/53.2BaF2 a 721. 118 0.46 67LiF/33MgF, 45.8LiF/54.2MgF0 a 724 16 o.eo 33.9Na3AlF6/66.lLi3AlF6 40Na AlF /60Li XlF a 725 114 3 6 3 6 0.61

70KF/30BaF2 43.6KF/56.4EaF2 729- 118 0.24 730 63. 7Na3AlF6/36. 3PbF2 60Na3AlF,/40PbF2 730 97,114 ZnF, ZnF2 734 137 0.48 11.3Na3AlF6/88.7NaCl 31. 5Na3AlF6/68. 5NaCl 734 129 0.09 66LiF/34MgF2 44.9LiF/55.lMgF2 735, 96,128,120 0.79 741, 121,30,46, 742, 54 746, 750, 749 34NaF/66MnF2 18.9NaF/81.1KnF~ e 738 118 57LiF/21CaF2/22SrF2 25. H.iF/27. 9CaF2/47SrF2 a 740 lie 0.58 20KF/30ZnF2 12.3KF/87.7ZnF2 e 740 116 0.45 83KFA7MnF2 75.3KF/24.7MnF2 e 743 118 726-750 6 5NaF/23CaF2/12MgF2 51.7NaF/34.lCaF2/14.2MgF2 e 745 9,101,117 0.07 37NaF/63FeF2 20.8NaF/79.2FeF2 a 745 118 80NaF/20ZrF4 50.lNaF/49.9ZrF4 a 747 118 1.23 NaZnF, NaZnF3 c 748 118 17LiF/29MgF2/54BaF2 3. 8LifA5.4MgF2/80. BBaF2 a 748 118 0.25 8lKF/19CoF2 71.9KF/28.1CoF2 750 116,119 41.9NaF/28.3AlF3/- 17NaF/2 3AlF3/6 OBaClj 750 114 0.16 29.8BaCl2 44KF/56BaF2 24.9KF/75.lBaF2 750 116 0.22 32NaFA8MgF2/50BaF2 12NaF/l0MgF~/78 BaF2 750 118 0.18 61NaFA9ZrF4 51.7NaF/48.3ZrF4 750 117 1.19

30LiF/32.8CaF,/37. 2BaF2 7.9LiF/26CaF7/66. lBaF2 758 118 0.28 3lNaF/34KF/35BaF2 13.8NaF/2lKF/65.2BaF2 759 118 0.20 79LiF/21CaF 55.6LiF/44.4CaF2 760, 118,122,116 0.92 2 765, 769 751-775 7.4Na3AlF,/68.0KF/- 24. 5Na,AlF,/62.1KF/8. 9LiF/- 21.8LiF/2.8Al203 4.5Al20, 760 114 0.38 83.5LiF/16.5BaF2 42 .8L1F/57.22BaFE , 765 116 0.81 86KFA4ZrF4 76.8KF/23. 2ZrF4 765 118 0.76 CuF, CuF, 770 95,120,135 1.34

60KF/40KP03 42.5KF/57.5KP03 e 776 119,131 52BaF2/21CaF2/27MgF2 73. 3BaF2A3. 2CaF2/13. 5MgF2 a 777 116 0.18 85KFA5MgF2 84.lKF/15.9MqF2 a 778 122,118 0.24 85.5NaF/14.5BaF2 84. 5NaF/15.5BaF2 a 778 96 0.09 79LiF/21CaF2 55.5L1F/44.5CaF2 a 780 120 0.92 KjTiF, K2TiFfe 780 39,97 0.35 776-800 L13AIF, LI3A1F, c ca 780 116 0.84 75LiF/?5AlF3 48.lLiF/51.9AlF3 c 792 16,120 0.84 77NaF/23NiF, 59.2NaF/40.8NiF2 a 795 118 0.9f 62. 5NaFA5KP/22. 5MgF2 53.6NaFA7.8KF/28.6MgF2 a 798 118 O.i: 52BaF2/21CaF2/27MgF2 73. 3BaF2/13. 2CaF2A3. 5MgF2 e 777 119 0.1E 8NaF/2lMgF2/7lBaF2 2.4NaF/5.3MgF2/68.3BaF2 e 800 118 0.2C

-204- TABLE XXXV. MELTING POINTS OF SELECTED IlETAL FLUORIDE SALTS (Continued) erature Typo Melting Range Composition Composition (e=et:tectic) Point Cost* (Mole %) (wt. %) (c^congruent) »c Roference S/lb. K P0»F K P F 3 2 3 °3 2 804 119 44NaF/26SrF2/30BaF2 804 118 0.23 66.7NaF/33.3CaF 17.0SaF/31.5SrF2/50.7BaF2 2 51.8NaF/48. 2CaF 810, 96,116,118 0.06 2 618 74NaF/26BaF2 40.5NaF/59.5BaF2 812 118 0.15 16KF/84(-nF2 10.6KF/89.4MnF, 814 118 801-825 33.4Na3AlF6/66.6BaF2 37. 5Na3;.lF6/C2r5BaF2 835 114 0.23 B3.3NaFA6T7FeF3 65NaF/35FeF3 820 22 PbF2 PbF2 622 79,80,99 30NaF/70BaF2 9.3NaF/90.7BaF2 825 116 0.20 37.5AlF3/62.5CaF2 39.2AlF3/60.8CaF2 820 0.07

75NaF/25MgF2 66.9NaF/33.lMgF2 830 118 0.08 37.5Na3AlF6/62. 5BaF2 33.4Na3AlF6/66.6BaF2 835 97 0.23 LiF LiF 842, 96,99,39, 1.62 e44, 12,112, 845, 122 640, 848 826-650 93KF/7A1F3 90.2KF/9.8A1F3 848 116 0.25 62.5KF/37.5CoF2 50KF/50CoF2 848 118 KZnF3 KZnF3 850 118 0.40 6NaF/36MgF2/56BaF2 2.7NaF/18.lMgF-/69. 2BaF, 850 118 0.17 50NaF/50SrF2 25.lNaF/74.9SrF2 ca 850 118 0.27 42. 2NaF/29. 2Na3AlF6/- 18.5NaF/64.lNa3AlF6/17.4KF 840 119 0.23 26.6KF

50NaF/50SrF2 25.1NaF/74.9SrF2 855 116 0. 27 KF KF 856 99 0.27 MnF2 MnF2 856 13,38,39, 99,120,137 851-875 K2P03F K2PO,F 857 119,131 Li3AlF6 Li3AlF, 858 93 0.64 6 ZnFo Zn£2 672 38,99,120, 0.48 112

90NaF/10CrF3 77.6NaF/22.4CrF3 878 119 0.75 75NaF/25SrF2 50.lNaF/49.9SrF2 879 115 0.20 37CaFA/6 3CaC03 31.4CaF2/68.6CaC03 880 119 0.02 876-900 75NaF/25BaF2 41.8NaF/58.2BaF2 682 115 0.15 65.7NaF/14. 3A1F3 75NaF/25.MF3 682 97 0.08 35.7MgF2/G4. 3BaP2 16. 5MgF?/83. 5BaF2 885 119 0.19 65NaF/35FeF3 40.9NaF/59.lFeF3 890, 112,124 692

52.2Na,AlFfi/47. BCaF, 74.6Na3AlF,/25.4CaF2 905 114 0.21 901-925 K,ZrF7 K3ZrF7 910 lie 1.31 15MgF2/85BaF2 5.9MgF,/94. lBaF2 910 118 0.20 57.5Na3AlF6/42. 5MgF2 82Na3AlF6/18MgF2 921 114 0.24

73BaF2/27BaCl, 69.5BaF2/30. 5BaCl2 930 119 0.21 926-950 52NajAlF,/48CaF2 74Na3AlP./26CaF2 945 97,20,118 0.16 42. 5MgF2757. 5K3AlFg 15.lMgF2784. 9K3AlF6 930 81 0.20

Na3AlF6/K3AlF6 Na3AlF6/K3AlF6 952 114 951-975 Ba3(FeF6)2 Ba3(FeF6)2 975 133 33NaFA3. SKF/53. 5MgF2 33.5NaF/46.2KF/20.3MgF2 975 118 0.17

52MgF2/48CaF2 46.4MgF2/53.6CaF2 980, 119,118 0.08 985 K3A1F6 K3A1F6 985 118 0.22 976-1000 NaF NaF 995 38,73,99, 0.07 100,112,115 64MgF,/36NaF 72.5MgF2/27.5NaF 987 0.10

Na3AlF6 Na3AlF6 1009 77,86,112, 0.27 114 1001-1025 3lKF/69MgF2 29. 5KF/70. 5MgF2 1008 118,122 0.16 K3A1F6 K3AlF6 1020 95,135 0.22

NaMgF3 NaMgF3 1030 118 0.09 26-1050 49CaF2/5lBaF2 30CaF2/70BaF2 1050 119 0.16

-205- TABLE XXXV. MELTING POINTS OF SELECTED METAL FLUORIDE SALTS (Continued) Temperature Type Melting Range Composition Composition (e^utectic) Point Coat* CC) (Mole %) (Wt. %) (c«=conqruent) •c Reference S/lb. 38KF/62CaP2 31.3KF/68.7CaF2 a 1060 42 0.12 1051­1100 KCaF3 KCaF3 c 1068 lie 0.14 KMgF3 KMgF, c • 1070 116,122 0.19 34.5KF/65. 5NiF2 24KF/76N1F, e 1084 118 1.77

MgF2 ngF2 1252 87,136 0.11 1251­1300 BaF2 BaFj 1280 39,112,137 0.21 38,79,60, 1301­1500 CaF5 CaF, 1416 0.05 95,99,120, 135,137

♦Costs are based on large scale manufacturing costs presented in Table XIX and market quotations for non­fluoride components as published in the November Chemical Marketer and Reporter. A 40% rate of return was assumed. Special handling and transportation charges are not included.

­206­ TABLE XXXVI. SELECTED METAL FLUORIDE SALTS

Temperature ttcltine Cost* A-4n Range Composition Composition (e-eutectic) Point S/Grara S/cc •C Mole % (wt. %) (c»ccnqruent *C f/ltx lO"4 <10"flKCal/mol«:al/n Cal/cc'

200-250 92NaF/8 SnP2 75.5NaF/24.5 SnFj e 240 2.3E 52.42

250-300 59.7Na3AlF6/40.3AlClj 70Na3AlF6/30AlCl3 e 300 3.2* 6.39

300-350 94KK/6SnF2 85.3KF/14.7SnF2 e 320 L.63 35.90

350-400 55KF/5AlF3/40ZrF4 31.0KF/4.lAlF3/64.9ZrF4 e 400 1.64 3.61 " 401-450 44LiF/12NaF/40KF/4MgF2 27.1L1F/11.9N3F/55.1KF/5.9MgF2 e 449 3.60 13.22 34.24 7.0 167 432 451-475 46.5L1F/11.5NaP/42KF 29. 2LiF'll. 7NaF'59. 1KF • 454 3.64 14.10 35.67 4.09 99.05 250

476-500 5L1F/S0KF/45A1F3 1.9L1F/42.6KF/55.SAlFj e 490 3.21 4.63

S01-52S 50NaF/50ZrF4 20.1NaF'79. 9ZrF. e 510 L.92 42.29 163.2( 6.4 61 235

526-550 12NaF/34KCl/54Na2C03 5.8KaF'28. 9<

551-575 14Na,C03/3eNaCl/48NaF 25.9Na2C03'38.8NaCl/35.3NaP « 575 3.04 0.88

576-600 16.SMgF2/63.5MgCl2 11.5MgF2'88.5HgCl2 • 596 3.07 1.54

601-625 52LiP/35HaF/13CaF2 35. 2HF/33. 3NaF/26. 5CaF2 e 615 3.61 13.44 37.90 5.83 152 429

626-650 67NaF/33ZnF2 45.2NaF/54.8ZnF2 « 635 3.29 6.39

651-675 32.3Na3AlF6/9.0AlF3/58.7CaF2 56Na3AlF6/6.2AlF3/37.8CaF2 e 675 3.24 5.29

676-700 35NaF/65NaCl 27.9NaF/72.1NaCl e 680 3.03 0.66

701-725 40NaF/60KF 32.5NaF/67.5KF e 721 3.21 4.62 LI.59 7.'22 140 3S1

726-750 6 5NaF/2 3Ca Fj/12MgF2 51.7NaF/34.lCaF2/14.2MgF2 e 745 0.07 1.54 4.57 6.7 135 401

751-775- 7.4Na3AlF6/68.0KF/21.8LiF/2.8Al203 24.5Na3AlF6/62.1KF/8.9L1F'4. SAljOj e 760 0.38 8.37

776-800 62. 5NaF/15KF/22.5MgF2 53.6NaF/17.8KF'28.6MgF2 e 7 98 0.12, 2.64 7.52

801-B25 &6.7NaF/33.3CaF2 51.8NaF/48.2CaF, e 310,81? 0.06 1.32 3.78 7.6S 141 403

826-850 7 5NaF/25MgF2 66.9NaF/33. lMgF2 e 830 0.08 1.76 S.17 9.27 155 459

/ 851-875 5Wvflf/0OStr2 25. lNaF 74.9SrFj e 855 0.27 5.95

676-900 B5.7NaF'14.3AlP3 75NaF'25AlF3 e 8B2 0.08 1.76

901-925 57.5NajAlF6/42.5MgP2 82Na3.MF6/ia".gF2 e 921 p.24 5.29

926-950 52Na3AlF6/48CaF2 74Na3AlF6/26CaF2 • 945 0.16 3.52

951-975 33NaP/13. 5KP/53. 5MgP2 33.5NaF'46.2KF'20.3KgFj e 975 0.17 3.74

976-1000 NaF NaF 995 3.07 1.54 3.94 7.97 190 486

1001-1025 31KF/69MgF2 29. 5KF/70.5MgF2 e 1008 3. 16 3.52

1026-1050 NaMgP3 NaMgFj e 1030 0.09 1.98 5.64 17.7 170 484

1051-1100 KMgF3 KMgFj c 1070 0.19 4.19

1251-1330 MgF2 MgF2 1252 3.11 2.42 7.61 13.9 223 698

1301-1500 CaF2 CaF, 1418 0.05 1. 10 j 4.19 7.1 90.9 346

* Sco text 1 r HJS-I ofj MiJ.i.cit Jena i 11 eg It is not possible at this time to determine the costs of the containers for the various heat storage systems, but it is certain that their costs will be a substantial part of the total cost of the systems. In many temperature ranges some salts are very inexpensive but their heats of fusion are much smaller than the more expensive salts. Without knowledge of the container cost, it is not possible to deter• mine accurately which salt will be the best for that tempera• ture range and therefore a certain amount of uncertainty exists for these selections. In many cases the materials in Table XXXV with highest energy densities/unit volume were not chosen for presentation in Table XXVI because cheaper materials with good energy densities are known. In other cases, not enough data are available for potentially attractive materials to be able to make a clearcut decision. In other words, the selections in Table XXXVI are the most attractive based on the available information, and when additional information becomes available, some of the selections are expected to change.

In the lowest temperature range, 200-250°C, 92NaF/8SnF2 was selected despite its relatively high cost. The large amount of NaF should result in a high heat of fusion. The

second best candidate is KHF2, but excess vapor pressure may be associated with this compound, particularly if the fusion temperature is exceeded very much during operational service.

In the 250-300° temperature range, 59.7Na3AlF6/40.3A1C1 has attracted our attention because of its low cost and the large proportion of energy dense molecules. Only expensive tin containing mixtures are candidates in the 300-350° range. The 94KF/6SnFp contains the least Sn and is selected. However, the hygroscopicity of KF would require additional special handling.

Between 350 and 400°, 55KF/5AlF3/40ZrF4 may have a high enough heat of fusion to offset its higher price relative to the boron containing mixtures that probably have lower heats

-208- of fusion. The 48LiF/52FeF_ composition is attractive on cost and probably on energy density bases, but corrosion is likely to be excessive.

In the 400-450° interval, 44LiF/12NaF/40KF/4MgF2, which melts at 449°, has the same energy/volume heat of fusion density (432 cal/cc) as the previously studied, widely quoted, and more expensive 20LiF/80LiOH mixture, mp 427°. The mixture 46.5LiF/ll.5NaF/42KF is the selection of choice in the 450-475° range.

Between 475 and 500°, 5LiF/50KF/45AlF3 should be investi• gated further because of acceptable cost and probable high storage capacity. The very low cost 18.5CaF„/81.5CaCl9 may have an improved heat of fusion over CaCl? (132 cal/cc) but equipment costs may be excessive for this relatively low energy dense material. The mixture of 25NaF/75NaP03 is attractive on a cost and availability basis, but .the heat of fusion and other essential thermodynamic and stability data are unavailable for this mixture.

, In the 500-525° range, the 79LiF/21ZrF4 probably has a very high volumetric energy density and might be suitable for use in applications insensitive to the cost of the storage medium. However, the heat of fusion of 50NaF/50ZrF4 has been found to be only moderate (235 cal/cc), and the inexpensive

25NaF/13KCl/62K2C03 also probably has low energy density. No suitable metal fluoride compositions are found in the 525-550° range, but between 550 and 575°, the mixture

14Na2C03/38NaCl/48NaF appears to be particularly attractive in terms of cost and probable heat of fusion. For extra high energy density, 18LiF/17NaF/65AlF3 may be the material of choice if the AlF3 vapor pressure is not too great. A particularly difficult choice of materials is presented in the 575-600° temperature interval. The 16.5MgF2/83.5MgCl2 mixture probably has a much lower heat of fusion than 40LiF/-

17NaF/43AlF3, but its 1/6 cost advantage may outweigh the

-209- increased equipment investment required by virtue of its hig? volume. The question of thermodynamic and stability properties

is again raised in the 600-625° region by 55NaF/45NaP03 and fundamental knowledge is also lacking for the lowest cost mixture in this group, 44NaF/56B„0_. If neither of these

materials is found to be suitable, then 35.2LiF/38.3NaF/26.5CaF2 with 429 cal/cc is the material of choice. A large number of interesting choices appear between 625

and 650°. Very low cost options are offerred by 30CaF2/70CaCl2

and 38.7NaF/6l.3Na3C03. A much higher heat of fusion is

expected for 36LiF/39MgF2/25SrFp and a very high energy/volume density of 526 cal/cc has been reported for 47LiF/43NaF/10MgF_. A good compromise between cost and efficiency is 67NaF/33ZnF~. Between 650 and 675°, 32. 3Na_AlF,./9. OAlF.,/58. 7CaF 'is our 7 3 6 3 2

cost-effective choice, but 3lNaF/40KF/29SrF2 may be a viable option once its heat of fusion is known. A high volume density (522 cal/cc) but premium cost material is 60LiF/40NaF. There are 11 options under $0.20/lb in the 675-700° range. We have chosen 35NaF/65NaCl because its low cost but probably substantial heat of fusion is difficult to exceed by materials in the $0.16-0.20/range. A 6-7 fold price differential is very substantial and difficult to overcome by high energy i densities of the more expensive salts. One candidate that may compete is 53.4NaF/46.6AlF3 at $0.10/lb. In the 700-725° range, 40NaF/60KF is the cost-effective material of choice. Two high energy density, premium cost materials are 67LiF/33MgF2 (630 cal/cc, $0.80/lb) and 64.4LiF/-

5.6KF/30MgF2 (628 cal/cc, $0.78/lb). The clear cost-effective high energy density choice between 725 and 750° is 65NaF/23CaF2/12MgF2. A premium cost material with very high energy density is 66LiF/34MgF2.

Between 750 and 775°, the choice is 30LiF/32.8CaF2/-

37.2BaF2 and from 775-800° the choice is 62.5NaF/15KF/22.5MgF2.

-210- The mixture 66.7NaF/33.3CaF2 was chosen for the 800-825° interval, but 37.5AlF3/62.5CaF2 is essentially as inexpensive and may be found to have a higher heat of fusion.

In the 825-850° range, 75NaF/25MgF2 is equally energy dense on a volume basis as LiF and is much less expensive, so there is no valid reason for continued interest in LiF by itself.

Between 850 and 875°, the 50NaF/50SrF2 mixture may have high enough energy density to be useful and between 875 and

900° 85.7NaF/14.3AlF3 should be considered. At the higher temperatures, the choices are less contro• versial, partly because the smaller number of candidates are practically all energy dense and because cost differentials are easy to separate. The selections for intervals between 900 and 1400°C are also given in Table XXXVI. A number of the compositions listed in Table XXXVI, especially in the intermediate temperature ranges, contain potassium fluoride, a compound that is difficult to keep, dry. However, KF should not be eliminated because of this property. All of the fluoride salts must be well dried before sealing in their containers and careful handling procedures must be used in order to ensure the purity of the materials. After manufacture, KF and the other metal fluorides should be kept and transferred under dry conditions. In addition, much of operational success depends on the elimination of corrosion, and the most promising method of this is the use of an aluminum or other getter material. This getter would be expected to remove last traces of moisture.

Other components listed in Table XXXVI contain the chloride ion. Although the corrosion caused by chlorides is recognized to be greater than that caused by fluorides, there are indica• tions that proper drying and use of getter techniques may substantially alleviate this potential problem.

-211- Although many AlF~ containing mixtures appear to be promising in a variety of temperature ranges, systematic examination for vapor pressure build-up will be a precautionary requirement.

Five of the mixtures in Table XXXVI contain lithium, an element generally assumed to have potential availability pro• blems. Calculations show that the amount of lithium contained in these mixtures ranges from 0.5 to 9.4% by weight.

-212- VII. EXPERIMENTAL The purity of the metal fluoride necessary for an efficient heat storage system is an important factor in the system's cost. In order to evaluate this necessary purity in a prelimi• nary way, we have roughly measured the heat of fusion of NaF samples doped with varying amounts of silicon dioxide. Silicon dioxide was chosen as the impurity because it is expected to be the major impurity in those fluorides obtained from the phosphate industry. The heats of fusion were roughly determined by differen• tial thermal analysis (dta) using a Dupont dta cell module and the Dupont thermal analyzer. Pure NaF (99.9%) was deter• mined by this technique to have a heat of fusion of approxi• mately 182 cal/g. Samples of SiO~ were then added to this same reagent grade NaF to give mixtures containing 5%, 3%,

and 1% Si02« These mixtures were intimately mixed, melted at 1000° in platinum crucibles sealed under N~, and ground to a fine powder. Each sample was run in duplicate and the results are as follows: Pure NaF 182 cal/g

99% NaF-1% Si02 169 cal/g

97% NaF-3% Si02 133 cal/g

95% NaF-5% Si09 130 cal/g These preliminary results suggest that less than 1% of impurity will not have a great effect on the heat of fusion;• however, larger amounts of impurity do effect the heat of fusion significantly. Further experiments of this nature are required, including a study of the effect of added alumi• num getter to pure and impure metal fluoride mixtures.

-213- VIII. SAFETY Recognized hazards associated with metal fluorides are essentially those of hydrofluoric acid and the component metals. Problems occur when the metal fluorides are allowed to hydrolyze and the following reaction occurs:

MF + H20 » MOH + HF Hydrofluoric acid is a particularly aggressive acid and caused burns to skin, eyes, and lungs. Extensive safety precautions are required whenever HF is present. As discussed in a pre• vious section, molten metal fluorides can hydrolyze completely in a moist environment. Several hours ax"e usually required for complete reaction, but at ambient temperature, reaction is much slower. For example, calcium fluoride, sodium tetra- fluoroborate, cryolyte, and other metal fluorides have survived natural conditions for geological eons. Nevertheless, inhaled metal fluoride dust should be assumed to damage lungs while dust left on the skin may cause burns. Although small quanti• ties of metal fluorides in drinking water are considered beneficial to human dental health, greater ingestion of metal fluorides is cavise for immediate medical attention.

These considerations require that suitable precautions are taken when charging and unloading heat storage equipment with metal fluorides. They also require that the equipment is sealed in a permanent manner. The question of hazard presented by ruptured molten fluoride-containing heat storage equipment has been addressed 9 280 experimentally. ' It was found that the fluorides rapidly solidified as a monolithic mass as they poured from the con• tainer and did not spread, thereby minimizing potential dust problems, rates of hydrolysis, and clean-up efforts. No fire, explosion, or reactive hazards were observed. Choice of metal candidates for metal fluoride heat storage systems is modified by consideration of relative

-214- toxicities of the elements. Thus, radioactive elements, cadmium, and arsenic are given little consideration. Beryllium fluoride must also be rejected because of its toxi• city. Both beryllium and its compounds can have both acute and chronic effects on humans. A number of human fatalities have been credited to beryllium and there is good evidence that it is carcinogenic.

-215- IX. RECOMMENDATIONS The following work is suggested as the next step in development of heat storage using metal fluorides: 1. Corrosion Rates The effect on corrosion of various metal fluorides should be investigated in greater detail by both accelerated and real• time experiments. Test containers should be constructed of materials that are suitable for cost-effective heat storage applications. Cycling parameters should be designed to reflect as closely as possible the end use conditions. The experiments should encompass all-fluoride systems, mixtures of fluorides and chlorides, mixtures of fluorides and carbonates, and some of the fluorides with lower heats of formation than the alkali and alkaline earths. The effects of impurities on corrosion should be investigated and the effects of getter materials should be investigated in greater detail. 2. Kinetics Any tendencies for chosen materials to supercool must be discovered. It is not sufficient to accept the statement that fluorides do not supercool as universal truth, because a systematic investigation has not been carried out and this parameter is too important to be left to assumption. Wall effects, purity, rate of crystallization, and cycle life need to be examined. 3. Purification In addition to the effects of impurities on kinetics, their effects on heat of fusion, melting point and other thermodynamic properties should be examined as functions of both quantity and type. The effects of getter additives on purity requirements need to be examined. 4. Transfer Metal fluoride transfer procedures need to be determined and their costs evaluated.

-216- 5. Thermophysical Data Some of the properties that are missing from the tables in this report need to be determined. In many cases, semi• quantitative procedures will suffice. Heats of fusion, for example, need to be determined for many of the AlF3, SnF-, MPO^F, and even some alkali and alkaline earth compositions. The eutectic composition(s) of MgF„ and AlF_ may be found to be particularly cost-effective.

-217- X. REFERENCES

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-237- THIS PAGE WAS INTENTIONALLY , LEFT BLANK Appendix I. Commercial Sources of Metal Fluorides ,

Part I. Metal Fluoride Source List

Compound Source''

Aluminum Fluoride AMP, ACA, ACN ADR, AFC, HST, ASC, APH, GSA BSC, DBM, CRC, ESP, MCE, FCC GSC, KNK, ITC, JHC, KLU, KBI PRO, MCB, MUI, OMC, ORI, OZM ROC, SBN, SPX, SFV

Anhydrous Hydrofluoric Acid ACN, APC, CAT DUI, EMD, ESX, HSH, KLU, MAT MGS, PAT, PGP, SGP, SF, SFV, TRI, THC, UCC Barium Fluoride ACS, ADR, AFC HST, APH, GSA, BKC, BNC, BDM 'BRN, CRC, EMD, ESP, FCC, GSC GWI, HSH, HCO, KNK, ITC, PRO MCR, ORI, OZM, PCR, PET, PNB PBC, REL, ROC, SNB, SPX, UMC ALF

Calcium Fluoride ACN, ADR, AFC HST, APH, ASI, GSA, BKC, BDM CEM, CRC, CSI, COT, DOW, ESP EMD, MCE, FIS, GEL, DFG, GWI HSH, KNK, IMC, ITC, KST, KRC MAL, PRO, MCB, MIL, MCL, MOC OZM, PCR, PES, REL, ROC, REY SAM, SHP, SPX, SYL, UMC, VWR VLO, ALF Calcium Hexafluorosilicate HST, KNK, PNB

Calcium Hexafluorotitanate CPL, CTY, KNK, PNB, VLO Calcium Monofluorophosphate MCB, OZM, ALF Calcium Tetrafluoroborate APH, ROC, ALF Cobalt Difluoride GSA, CRC, CPL, CTY, ESP, EMD, GWI, HSH, PRO, OZM, PCR, ROC, RMR, ALF

Cryolite (Same as Sodium Aluminum Fluoride)

Cupric Fluoride APH, GSA, BDM, CRC, CLB, ESP, DFG, HCO, KNK, MCB, OZM, PCR, PNB, ROC, UMC, VLO, ALF

Ferric Fluoride ADR, GSA, BCL, BDM, CRC, CPL, CTY, CLB, ESP, EMD, DFG, KNK, MCB, MID, ORI, OZM, ROC, ALF -239- Appendix I. Commercial Sources of Metal Fluorides (Cont Part I. Metal Fluoride Source List

2 Compound Source Ferric Tetrafluoroborate ACS, HST, GSA, HCC, MKC, ALF

Ferrous Fluoride GSA, BDM, CLB, DFG, KNK, OZM, PCR, PNB, VLO, ALF Fluorosilic Acid AGO, ADM, AIC, APH, ASM, ASI, CHT, CTE, EMD, ESX, FIS, FRP, GDI, GRA, HSH, HAW, IMC, ICG, JCI, KER, MCB, MKC, MIS, OMC, RBC, SBN, SOC, SFF, TGI, THC, UAL, VNP, ALF Fluorspar

Hydrofluoric Acid ACA , ACN, ACS, APC, ADR, APH, ASI , GSA, BKC, CAT, CSI, CHT, COM , CCC, DA, DUI, EMD, ESX, FCC , FIS, GSC, CPH, HSH, HCC, HUK » JTC, KBI, KLU, LVC, MAL, MAT' , MCB, MKC, OMC, PAT, SAN, 'SGP > SFV, THC, TRI, UHE, UCC, VWR , ALF Hydrogen Fluoride (anhydrous ACN , APC, CAT, DUI, EMD, ESX, hydrofluoric acid) HSH , KLU, MAT, MGS, PAT, PGP, SGP , SF, SFV, TRI, THC, UCC ADC » AFC, HST, APH, GSA, BAR, CRC » CPL, CTY, ESP, EMD, FLD, Lead Difluoride GSC » GWI, KNK, PRO, MCB, ORI, OZM , PCR, REL, ROC, SYL, UMC, ALF ACE , ACS, AFC, HST, GSA, BKC, BNC' BDM, CRC, CPL, CSI, CLB, Lithium Fluoride ESP, EMD, FIS, FTE, DFG, HSH, KNK KBI, LCA, PRO, MCB, ORI, OZM', PCR, ROC, SPX, SYL, TRI, UMCJ ALF, VWR, VLO Lithium Hexafluorosilicate GSA CTY, KNK, LCA, ORI, PNB, ROCJ ALF Lithium Hexafluorotitanate CPL, KNK, ORI, OZM, ALF Lithium Monofluorophosphate GSA Lithium Tetrafluoroborate APH GSA, BDM, FTE, DFG, KNK, MCB \ ORI, OZM, ALF -21+0- Appendix I. Commercial Sources of Metal Fluorides (Cont'd)

Part I.Metal Fluoride Source List

Compound Source'' Magnesium Fluoride AFC HST, APH, GSA, BAR, BDM, CRC DCC, ESP, EMD, FLD,- GSC, DFG HSH, KNK, ISC, ITC, KBI, KOI ADM, MAL, PRO, MCB, ORI, OZM PCR, ROC, SPX, SYL, TRI, VLO ALF Magnesium Hexafluorosilicate AGO HST, GSA, GSC, ICC, ITC, MCB MKC, MOB, ORI, PET, RIN, SBN HSC. ALF

Magnesium Tetrafluoroborate HSH OZM

Manganous Fluoride ACS , HST APH, GSA, BAR, CRC, CTY , EMD GSC, GWI, KBI, PRO, MCB., OZM PNB, ROC, VLO, ALF Nickel Fluoride APC APG ACS, ADR, APH, GSA, BDM , CRC CTY, ESP, DFG, KNK, PRO , MCB MNT, ORI, OZM, PCR, REL ROC UMC, VLO, ALF Potassium Fluoride ACS ALC ADR, HST, APH, ASI, GSA BKC BDM, CSI, CON, DCC, EMD FCC FIS, HSH, MAL, MCB, ML I ORI OZM, PCR, REL, ROC, RUG SHA TRI, UHE. UMC, VWR, ALF

Potassium Hexafluoroaluminate GCC, KNK KBI, ORI, PET, PNB, ROC. SBN ALF Potassium Hexafluorosilicate AGO APH BEN, BEC, BOR, BRN, FBI GSC HEL, HHC, HUX, ICC, KNK, ITC KBI, KCC, MEI, MKC, MCL. PET PNB, RIN. SMD, SBN. HSC

Potassium Hexafluorotitanate AFD. HST GSA, CTY, GCC, HSH, KNK ITC KBI, LPI, MCL, PET, PNB. ROC ALF

Potassium Monofluorophosphate CPL KNK ORI, OZM, ROC

Potassium Tetrafluoroborate ACS ADR AFD. HST, APH, BOR, BRN GCC HSH, ITC, KBI, LPI, MCB OZM PET, PBC, SMD, SBN, THC TRI ALF

-21+1- Appendix I. Commercial Sources of Metal Fluorides (Cont

Part I. Metal Fluoride Source List

Compound Source'

Potassium Zinc Fluoride CTY, PET, OZM

Sodium Aluminum Fluoride AMP, ACA, ADR, AFC, HST, AGN, (Cryolite) GSA, CEM, CRC, DOR, MCE, FCC, FIS, HSH, HUX, ICC, IGP, INL, KNK, ITC, KLU, KRC, MCB, MOB, MUI, OZM, PAT, PNB, REY, RIN, ROC, SBN, TWO, WCI, ALF

Sodium Fluoride ACN, ACS, ITC, AFC, HST, APH, ASI, GSA, BKC, BCI, BDM, BRI, BRN, CMI, CRC, CSI, CHT, DCC, ESP, EMD, FBI, FIS, HSH, HOW, ICC, IGP, KNK, INL, JTC, KBI, KCC, KOI, KRC, MAL, PRO, MKC, MCB, MCL, MOB, MCC, OMC, ORI, OZM, PNB, PBC, POS, REL, RIN, RUG, SHP, SIG, SBN, THC, TWO, UHE, UMC, VWR, ALF, YCM

Sodium Hexafluorosilicate AGO, ACA, AFC, AMI, APH, ASM, ASI, BEN, BCI, BRN, CSI, CHT, CNC, DCC, ESX, FBI, FIS, GDI, HSH, HOW, HUX, ICC, IGP, KNK, ICE, ITC, JHC, JCI, JTC, KLU, KBI, KER, KCC, KRC, MEI, MCB, MKC, OMC, PET, PNB, PBC, PSC, POS, PRI, ROC, RDA, RIN, ROB, EMS, SBN, HSC, TAR, THC, VWR, YCM

Sodium Hexafluorotitanate GSA, CTY, KBI, PNB, ROC

Sodium Monofluorophosphate ADR, APH, GSA, BDM, CPL, CLB, ESP, DFG, KNK, MCB, ORI, OZM, PCR, PNB, ROC, RDA, ALF

Sodium Tetrafluoroborate ACS, ADR, HST, APH, CPL, DCC, GSC, GCC, HSH, KBI, MCB, OZM, PCR, PET, PBC, ROC, THC, ALF

Sodium Zinc Fluoride CTY

Stannous Fluoride HST, GSA, BAR, CRC, CPL, DOM, ESP, MCB, MNT, OZM, PCR, PNB, REL, ROC, SIG, SHA, ALF

-21+2- Appendix I. Commercial Sources of Metal Fluorides (Cont'd)

Part I. Metal Fluoride Source List

Compound Source Stannous Monofluorophosphate GSC, KNK, ORI, OZM, PNB, ROC

Strontium Fluoride HST , APH, GSA, BNC, CRC, CPL, ESP , EMD, GEL, HSH, KNK, MAL, PRO » ORI, OZM, PNB, REL, ROC, SPX > SYL5 UMC, VLO, ALF

Titanium Tetrafluoride ADR • APH> GSA, BDM, CRC, CPL, ESP , DFG, KNK, ORI, OZM, PCR, PNB > VLO, ALF Zinc Fluoride ADR , HST, APH, GSA, BAR, BCL, BDM » CPL,. CSI, CTY, CLB, ESP, EMD DFG, GWI, HCO, KNK, PRO, MCB OZM, PCR, PNB, ROC, UMC, VLO. ALF Zinc Hexafluorosilicate AGO HST, ASI, BEC, BRN, GSC, GCC ICC, KNK, MKC, PNB, RIN, ROB. SBN, HSC, ALF

Zinc Tetrafluoroborate ACS. HST, APH, GSA, CPC, HAR, HSH. HCC, KNK, ICT, MKC, MCR, PNB, REL, ROC, SAN, THC, ALF Zirconium Tetrafluoride GSA, ESP, EMD, PRO, OZM, ROC, VLO, ALF

1. Current Manufacturers and/or Supp]iers were taken from the following sources:

1) 1975-76 CPD Chemical Buyers Directory by Chemical Marketing Reporter, Schnell Pub. Co., N. Y., N. Y, 2) 1976 Buyers Guide Issue of Chemical Week by McGraw-Hill, N. Y.,N. Y. 3) 1977 Buyers Guide Issue of Chemical Week. 4) 1976-77 Chemical Directory of Chemical Purchasing by Myers Pub. Co., N. Y., N. Y. 5) 1976 Ed. Chemical Sources - USA by Directories Pub. Co., Flemington, N. J.

2. The code system is taken from reference 5 above. See the separate list for company addresses and phone numbers of the main offices.

-21+3- Appendix I. Commercial Sources of Metal Fluorides

Part II. Company Addresses

ACA Alcoa, 1501 Alcoa Bldg., Pittsburgh, Pa. 15219, 412-553-2597 ACE Aceto Chemical Co., Inc., 126-02 Northern Blvd., Flushing, ' N. Y. 11368, 212-898-2300 ACN Allied Chemical Corp., Industrial Chemical Div., P. 0. Box 1139R, Morristown, N. J. 07960, 201-455-2000 ACS Allied Chemical Corp., Specialty Chemicals Div., P. 0. Box 1087R, Morristown, N. J. 07960, 201-455-2000 ADC Amend Drug & Chemical Co., Inc., 83 Cordier St., Irvington, N. J. 07111, 201-926-0333 ADM A. D. Mackay, Inc., 198 Broadway, New York, N. Y. 10038, 212-227-8532 ADR American Drug & Chemical Co., 3555 Hayden Ave., Culver City, Co. 90230, 213-559-0200 AFC American Fluoride Corp., 17 Huntington Place, New Rochelle, N. Y. 10801, 914-633-7005 AFD American Firstoline Div. of Intsel Corp., 825 Third Ave., New York, N. Y. 10022, 212-758-5880 AGN Armageddon Chemical Co., 431 Salem St., Durham, N. C. 27703, 919-596-5426 AGO Agrico Chemical Co., P. 0. Box 67, Polk County, Pierce, Fla. 33867, 813-428-1431 AGO Agrico Chemical Co., 9 East 4th St., Tulsa, OK.74101, 918- 583-1711 AIC Americhem, 340 North St., Mason, MI 44854, 517-677-3211 ALC Alloychem, Inc., 641 Lexington Ave., New York, N. Y. 10022, 212-421-6300 ALF Ventron Corp., Alfa Products, 152 Andover St., Danvers, MA. 01923, 617-777-1970 AMI American International Chemical Inc., 209 W. Central St., Natick, MA. 01760, 617-655-5805 AMF Alcan Sales, Div. Alcan Aluminum Corp., Ill West 50th St., New York, N. Y. 10020, 212-582-2070 APC Air Products & Chemicals, Inc, Industrial Gas Div., P. 0. Box 538, Allentown, PA. 18105, 215-395-8105 APG Air Products & Chemicals, Inc., Industrial Gas Div., P. 0. Box 538, Allentown, PA. 18105, 215-395-8105 APH. Apache Chemicals, Inc., P. O. Box 126, Seward, 111. 61077, 815-247-8491 ASC Amersham/Searle, 2636 Clearbrook Dr., Arlington Heights, 111. 60005, 312-593-6300 ASI Ashland Chemical Co., Industrial Chemicals & Solvents Div. P. O. Box 2219, Columbus, Ohio 43216, 614-889-3333 ASM Asher-Moore Co., Div. of Prillaman Chemical Corp., P. 0. Box 3615, Richmond, VA. 23234, 804-748-8123 BAR Barker Industries Inc., Off U. S. Highway 221, Ora, S. C. 29371, 803-682-3121 BCL Bio-Clinical Labs, Inc., 30 Tower Place,; Smithtown, N. Y. 11787, 516-567-6677 BEC Berkshire Chemicals Inc., 155 E. 44 St., New York, N. Y. 1001/, 212-986-8855 BEN Bentley Chemical Corp., 190 North Canon Dr., Beverly Hills, CA. 90210, 213-272-9946 -21+1+- Appendix I. Commercial Sources of Metal Fluorides (Cont'd)

Part II. Company Addresses

BKC J. T. Baker Chemical Co., 222, Red School Lane, Phillipsburg, N. J. 08865, 201-859-2151 BNC Barium & Chemicals, Inc, P. O. Box 218, Steubenville, OH. 43952, 614-282-9776 BDM Bodman Chemicals, P. O. Box 500, Media, Pa. 19063, 215-459-5600 BOR Borden Chemical, Div. of Borden, Inc., 180 E. Broad St., Columbus, OH. 43215, 614-225-4000 BRI Brinkmann Instruments, Cantiague Road, Westbury, N. Y. 11590, 516-334-7500 BRN Browning Chemical Co., 295 Madison Ave., New York, N. Y. 10017, 212-532-7900 BSC Biddle Sawyer Corp., 2 Penn Plaza, New York, N. Y. 10001, 212- 736-1580 CAT Cationics, Inc, 4706 B Beidler Rd., Willoughby, OH. 44094, 216-461-9861 CCC Corco Chemical Corp., Tyburn Rd. & Cedar Lane, Fairless Hills, Pa. 19030, 215-295-5006 CEM C-E Minerals, Div. of Combustion Eng., 901 E. Eight Ave., King of Prussia, Pa. 19406, 215-265-6880 CHT Chemtech Industries, Inc., 9909 Clayton Rd., St. Louis, Mo. 63124, 314-997-4600 CLB Columbia Organic Chem. Co., P. O. Box 9096, Columbia, S. C. 29290, 803-776-4990 CMI Cemco, Inc., 363 Ponus Ridge Rd., New Canaan, Conn. 06840, 203-966-8777 CNC Columbia Nitrogen Corp./Nipro Inc., P. O. Box 1483, Augusta, Ga. 30903, 404-724-8771 CON Conservation Chemical Co., 215 West Pershing Rd., Suite 703, Kansas City, Mo. 64108, 816-421-8494 COT Cotronics Corp., 37 W. 39th St., New York, N. Y. 10018, 212- 531-9376 CPC CP Chemicals Inc., Arbor St., Sewaren, N. J. 07077, 201-636- 4300 CPH C. P. Hall Co., 7300 S. Central Ave., Chicago, 111. 60638, 312-767-4600 CPL Chemical Procurement Labs Inc., 18-17 130th St., College Point, N. Y. 11356, 212-353-2663 CRC Cerac, Inc., P. 0. Box 1178, 407 N. 13 St., Milwaukee, WI. 53201, 414-289-9800 CSI Chem. Service, Inc., 815 Lincoln Ave., West Chester, Pa. 19380, 215-692-3026 CTE Cities Service Company, Ind. Chem. Mkt. Dept., 3445 Peachtree Rd., NE, Atlanta, Ga. 30326, 404-261-9100 CTY City Chemical Corp., 132 West 22nd St., New York, N. Y. 10011, 212-929-2723 DCC Davos Chemical Corp., 2500 Lemoine Ave., Fort Lee, N. J. 07024, 201-461-591 2MD E. M. Laboratories, Inc., 500 Executive Blvd., Elmsford, N. Y. 10523, 914-592-4660 DOM Dorman Chemicals, Inc., 130 Wesley St., S. Hackensack, N. J. 07606, 201-345-6780 -21+5- Appendix I. Commercial Sources of Metal Fluorides (Cont'd)

Part II. . Company Addresses

DOR P. H. Doremus Chemical Co., 638 E. 19th St., Paterson, N. J. 07514, 201-684-5661 DOW Dow Chemical Co., 2020 Dow Center, Midland, MI. 48640, 517- 636-1000 DSC Diamond Shamrock Corp., 1100 Superior Ave., Cleveland, OH. 44114, 216-694-5224 DUI E. I. DuPont De Nemours & Co., Inc., Industrial Chemicals Dept., 1007 Market St., Wilmington, DE. 19898, 302-774-2421 EMS E. M. Sergeant Pulp & Chemical Co., 7 Dey St., New York, N. Y. 10007, 212-962-4340 ESP Electronic Space Products, Inc., 854 S. Robertson Blvd., "Los Angeles, CA. 90035, 213-657-5540 ESX Essex Chemical Corp., 1401 Broad St., Clifton, N. J. 07015, 201-773-6300 FBI Faesy & Besthoff Inc., 143 River Rd., Edgewater, N. J. 07020, 201-945-6200 FCC Filo Color & Chemical Corp., 347 Madison Ave., New York, N. Y. 10017, 212-684-7080 FIS Fisher Scientific Co., 711 Forbes Ave., Pittsburgh, Pa. 15219, 412-562-8300 FLD Fielding Chemical Co., P. O. Box 21, 100 Halladay St., Jersey City, N. J. 07305, 201-433-1324 FRP Freeport Chemical Co., Div. Freeport Minerals Co., 161 E. 42 St., New York, N. Y. 10017, 212-687-8100 FTE Foote Mineral Co., Route 100, Exton, Pa. 19341, 215-363-6500 GCC Graymor Chemical Co., Inc., 43 U. S. Highway 46, Pine Brook, N. J. 07058, 201-575-7820 GDI Gardinier Inc, U. S. Phosphoric Prod., P. O. Box 3269, Tampa, Fla. 33601, 813-677-9111 GEL General Electric Co., 21800 Tungsten Rd., Cleveland, OH. 44117, 216-266-2451 DFG D. F. Goldsmith Chem. & Metal Corp., 909 Pitner Ave., Evanston, 111. 60202, 312-869-7800 GRA W. R. Grace & Co., Agricultural Chemicals Group, P. 0. Box 277, Memphis, Tenn. 38101 901-522-2000 GSA Atomergic Chemetals Co., 584 Mineola Ave., Carle Place, N. Y. 11514 (Division of Galla rd-Schlesinger), 516-333-5600 GSC Gallard-Schlesinger Chem. Mfg,^ Corp., 584 Mineola Ave., Carle Place, N. Y. 11514, 516-333-5600 GWI Great Western Inorganics, Inc., 17400 Highway 72, Golden, Co. 80401, 302-423-9770 HAR Hardwicke Chemical Co., Sub. McLaughlin Gormley King Co., Route 2, Box 50A, Elgin, S. C. 29045, 803-438-3471 HAW Hawkins Chemical Inc., 3100 E. Hennepin Ave., Minneapolis, Minn. 55413, 612-531-6910 HCC Harstan Chemical Co., 1247 38 St., Brooklyn, N. Y. 11218, 212-435-8225 HCO Heico, Inc., Delaware Water Gap, Pa. 18327, 717-476-0353 HEL Helm Chicago Chem. Corp., 880 Hartford Plz., 150 S. Hacker Dr., Chicago, 111. 60606, 312-782-8132 HHC Helm Houston Chem. Corp., 1100 Milam Bldg., Suite 2740, Houston, TX. 77002, 713-237-1187 -21+6- /appendix I. Commercial Sources of Metal Fluorides (Cont'd)

Part II. Company Addresses

HOW Howe & French, Box 730, Colonial Rd., Salem, Mass. 01970, 617-745-7250 HSH Harshaw Chemical Co., Div. Kewanee Oil Co., 1945 East 97th St., Cleveland, Ohio 44106, 216-721-8300 HSC Henry Sundheimer Co., 300 Hamilton Ave., White Plains, N. Y. 10601, 914-946-3744 HST American Hoechst Corp., Chemicals & Plastics Div., Chemical Dept., Route 202-206 North, Somerville, N. J. 08876, 201-685- 2000 HUK Hukill Chem. Corp., 7013 Krick Rd., Bedford, OH. 44146, 216- 232-9400 HUX Huxley Development Corp., 1271 Ave. of the Americas, New York, N. Y. 10020, 212-581-0660 ICC ICC Solvent Chemical Sales Corp., 720 5 Ave., New York, N. Y. 10011, 212-397-3375 ICE International Commodities Export Co., 110 Wall St., New York, N. Y. 1Q005, 212-747-1670 ICG IMC Chemical Group Inc, Electrochemicals Div., 52 Sobin Pk., Boston, MA. 02210, 617-268-5100 ICT Intercontinental Cavalier Corp., 3901 8th Ave., Brooklyn, N. Y. 11232, 212-633-1000 , IGP ICD Group, 641 Lexington Ave., New York, N. Y. 10022, 212- 644-1494" IMC International Minerals & Chemical Corp., Industry Group, 245 Park Ave., New York, N. Y. 10017, 212-661-4300 INL International Chemical Corp., 720 Fifth Ave., New York, N. Y. 10019, 212-582-2020 ISC Interstate Chemical Corp., 1625 Lemoine Ave., Fort Lee, N. J. 07024, 201-947-9666 ITC Intsel Corp., Chemical Div., 825 Third Ave., New York, N. Y. 10022, 212-758-5880 JCI Jones Chems, Inc., Dept BG, 100 Sunny Sol Blvd., Caledonia, N. Y. 14423, 716-538-2311 JHC Jayan-Hoag Chemical Co., Inc., 8620 North Ferris Ave., Morton Grove, 111. 60053, 317-965-6650 JTC Joseph Turner & Co., Ridgefield, N. J. 07657, 201-945-8383 KBE Kawecki Berylco Industries, Inc., 220 E. 42 St., New York, N. Y. 10017, 212-682-7143 KCC Koch Chemical Co., Inc., 888 Worcester St., Wellesley Hills, MA. 02181, 617-237-5477 KER Kerr-McGee Chemical Corp., Kerr-McGee Center, Oklahoma City, OK. 73125, 405-236-1313 KLU Kaiser Chemicals, Div. of Kaiser Aluminum, 300 Lakeside Drive, Oakland, Calif. 94643, 415-271-5580 KNK ICN-K+K Life Sciences Group, 121 Express St., Plainview, N. Y. 11803, 516-433-6262 KOI Koch Oil International Co., 1271 Ave. of the Americas, New York, N. Y. 10020, 212-541-8570 KRC Kraft Chemical Co., 917 West 18th St., Chicago, 111.. 60608, 312-733-1919 KST Kemstar Corp., 92 Revolutionary Rd., Scarborough, N. Y. 10510, 914-762-3188 -21+7- Appendix I. Commercial Sources of Metal Fluorides (Cont'd)

Part II. Company Addresses

LCA Lithium Corp. of America, 449 North Cox Road, Gastonia, N. C. 28052, 704-867-8371 LPI Laporte Industries Ltd., Hanover House, 14 Hanover Square, London WIR OBE, England, 01-629-6603 LVC Lehigh Valley Chem. Co., Div. of Ashland Chem. Co., P. 0. Box 350 - RD 4, Easton, Pa. 18042, 215-258-9135 MAL Mallinckrodt Inc, Second & Mallinckrodt Sts., P. 0. Box 5439, St. Louis, Mo. 63147, 314-231-8980 MAT Matheson Gas Products, 932 Paterson Plank Rd., E. Rutherford, N. J. 07073, 201-933-2400 MCB MC & B Manuf. Chemists, 2909 Highland Ave., Cincinnati, OH. 513-631-0445 MCC Mutchler Chemical Co., Inc., 259 Broadway, New York, N. Y. 10007, 212-349-4735 MCE Engelhard Minerals & Chem. Corp., 2655 U. S. Highway 22, Union, N. J. 07083, 201-589-5000 MCL Minerals & Chemicals Ltd., 1117 St. Catherine St., West, Montreal, Que., Canada H3B IH9, 514-849-6366 MCR MCR Corp., 800 Briar Creek Rd., Charlotte, N. C. 28205, 704- 372-4807 MEI Magnesium Elektron, Inc, Star Route A, Box 202-1, Flemington, N. J. 08822, 201-782-5800 MGS M. G. Scientific, Member of Hoechst Group, 1000 Harrison Ave., Kearny, N. J. 07029, 201-991-0100 MID Mide Chemical Corp., 375 Central Ave., Bohemia, N. Y. 11716, 516-567-6366 MIL Milwhite Co., Inc., P. 0. Box 15038, 5800 Lyons Ave., Houston, Texas 77020, 713-675-0961 MIS Mississippi Chemical Corp., P. 0. Box 388, Yazov City, Miss. 39194, 601-746-4131 MKC McKesson Chemical Co., Crocker Plaza, One Post St., San Francisco, CA. 94104, 415-983-8300 MLI Marshallton Research Lab., Box 11646, Winston Salem, N. C. 27106, 919-983-2131 MNT M & T Chemicals Inc., Subsidiary of American Can Co., Wood- bridge Road, Rahway, N. J. 07065, 201-499-0200 MOB Mobay Chemical Corp., Pky. W. & Rte. 22-30, Pittsburgh, Pa. 15202, 412-923-2700 MOC Minerva Oil Co., Fluorspar Mining Div., P. 0. Box 531, Eldorado, 111. 62930, 618-273-2191 MUI Montedison U. S. A., Inc., 1114 Ave. of the Americas, New York, N. Y. 10036, 212-764-0260 OMC Olin Corp., 120 Long Ridge Rd., Stamford, Conn. 06904, 203- 356-2000 ORI Orion Chemical Co., P. 0. Box 8617, Glendale, CA. 91214, 213- 249-9 911 OZM Ozark-Mahoning Co., Div. of Pennwalt, 1870 S. Boulder, Tulsa, OK. 74119, 918-585-2661 PAT Pennwalt Corp., Indchem Div., Pennwalt Bldg., 3 Parkway, Philadelphia, Pa. 19102, 215-587-7000 PBC Phillipp Brothers Chemicals, Inc., 10 Columbus Circle, New York, N. Y. 10019, 212-586-6020 -21+8- Appendix I. Commercial Sources of Metal Fluorides (Cont'd)

Part II. Company Addresses

PCR PCR Inc, P. 0. Box 1466, Gainesville, FL. 32602, 904-376- 8246 PES Pesses Co. (The), 29605 Hall St., Solon, OH. 44139, 216-248- 0145 PET Pettibone-Chicago, Inc., 435 N. Michigan Ave., Chicago, 111. 60611, 312-944-0777 PGP Precision Gas Products, Inc, 681 Mill Street, Rahway, N. J. 07065, 201-381-7600 PNB Pfaltz & Bauer, Inc., 375 Fairfield Ave., Stamford, Ct. 06902, 203-357-8700 POS Polysciences, Inc, Paul Valley Indust. Park, Warrington, Pa. 18976, 215-343-6484 PRI Prior Chemical Corp., 420 Lexington Ave., New York, N. Y. 10017, 212-532-9811 PRO Materials Limited, 1 Edison Place, Fairfield, N. J. 07006, 201-227-6211 PSC Pioneer Salt & Chemical Co., 940 N. Delaware Ave., Philadel• phia, Pa. 19123, 215-574-8500 RBC Robinson Brothers Chemicals Inc., 255 Randolph St., Brooklyn, N. Y. 11237, 212-497-0043 RDA Rhodia, Inc, Chemicals Div., 120 Jersey Ave., New Brunswick, N. J. 08903, 201-846-7700 REL Reliable Chemical Co., P. 0. Box 12442, St. Louis, Mo. 63132, 314-997-7200 REY Reynolds Metals Co., 6601 West Broad St., Richmond, Va. 23261, 804-282-2311 RIN Riches-Nelson, Inc, 170 Mason St., Greenwich, Conn. 06830, 203-869-3088 RMR Rocky Mountain Research Inst., South Bellaire, Denver, Co. 80222, 303-753-0122 ROB Robeco Chemicals, Inc., 51 Madison Ave., New York, N. Y. 10010, 212-683-7500 ROC Research Organic/Inorganic Chem. Co., 507-519 Main St., Belleville, N. J. 07109, 201-759-3700 RUG Ruger Chemical Co., P. 0. Box 806, Hillside, N. J. 07295, 201-926-0331 SAM Samincorp, Inc., 725 Park Ave., New York, N. Y. 10022, 212- 644-6780 SAN Sanolite Chem. Corp., 3449 Ft. Hamilton Pky., Brooklyn, N. Y. 11218, 212-633-8011 , SBN Sobin Chemicals Inc. (IMC Chem. Group), Ind. Chem. Div., Sobin Park, Boston, Mass. 02210, 617-268-5100 SFF Stauffer Chemical Co., Fertilizer & Mining Div., 636 Calif• ornia St., San Francisco, CA. 94119, 415-434-1800 SFT Stauffer Chemical Co., Specialty Chem. Div., Westport, Ct. 06880, 203-226-1511 SFV Stauffer Chemical Co., Industrial Chemical Div., Westport, Conn. 06880, 203-226-1511 SGP Scientific Gas Products, Inc., 2330 Hamilton Blvd., South Plainfield, N. J. 07080, 201-754-1100 SHA Shakti International Inc., P. 0. Box 156, Grand Island, N. Y. 14072, 716-773-1234 -21+9- Appendix I. Commercial Sources of Metal Fluorides (Cont'd)

Part II. Company Addresses

SHP Shepard Chemical Industries, Inc., 515 Madison Ave., New York, N. Y. 10022, 212-421-5815 SIG Sigma Chemical Co., P. 0. Box 14508, St. Louis, Mo. 63178, 314-771-5750 SMD Smith-Douglass Div., Borden Chemical, Borden Inc., P. 0. Box 419, Norfolk, Va. 23501, 804-461-7200 SOC Southchem Inc., P. 0. Box 886, Durham, N. C. 27702, 919-688- 8046 SPX Spex Industries, Inc., Box 798, Metuchen, N. J. 08840, 201- 549-7144 SYL GTE Sylvania Inc., Chemical & Metallurgical Div., 7G Hawes St., Towanda, Pa. 18848, 717-265-2121 TAR T. R. America Inc., 122 E. 42 St. (Suite 2100 Chanin Bldg.), New York, N. Y. 10017, 212-867-0116 TGI Texasgulf Inc., 200 Park Ave., New York, N. Y. 10017, 212- 972-5000 THC Thompson-Hayward Chemical Co., 5200 Speaker Rd., Kansas City, KS. 66106, 913-321-3131 TRI Tridom Chemical, Inc., 255 Oser Ave., Hauppauge, N. Y. 11787, 516-273-0110 TWO Transworld Chemicals Inc., 246 E. State St., Suite 5, Westport, Ct. 06880, 203-226-7181 UAL USS Agri-Chemicals, Div. U. S. Steel Corp., P. O. Box 1865, 30 Pryor St., Atlanta, Ga. 30301, 404-522-2641 UCC Union Carbide Corp., Linde Div., 270 Park Ave., New York, N. Y. 10017, 212-551-3763 UHE UHE, George Co. Inc., 76 9 Ave., New York, N. Y. 10011, 212- 929-0870 UMC United Mineral & Chemical Corp., 129 Hudson St., New York, N. Y. 10013, 212-966-4330 VLO Var-Loc-Oid Chem. Co., 666 S. Front St., Elizabeth, N. J. 07202, 201-289-3630 VNP Valley Nitrogen Producers, Inc., P. 0. Box 1752, 1221 Van Ness Ave., Fresno, CA. 93717, 209-486-0100 VWR Van Waters & Rogers. Div. of Univar, P. 0. Box 3200, 3745 Bayshore Blvd., San Francisco, CA. 94119, 415-469-0100 WCI Westco Chemicals, Inc., 11312 Hartland St., North Hollywood, CA. 91605, 213-984-0130 YCM Young Chemical Co., 24700 Center Ridge Rd., Cleveland, OH. 44145, 216-835-2200

-250- Appendix II ­ Supply­Demand Relationships of Metals

ALUMINUM SUPPIV­DEMAND RElATIONSHlPS­1974

WOCIO ft ODUC1ION « ' 1

WITIO mm 4SI counucio* OOMMICM ut UUUM uis KHMUC tmrni iwin mocjcist T" 1.149 tic 144 mi*T i 1»4S l nuntraaiiicB LOS) iwn IM MV! lucnoui m •own uuuu US KMMH una nxumml ~H»14.4t III! 4J01, J­ MfTAl 1.4)49 CAM WO CWH44WKS aim. MUU MUST*) nocu IE) m 10 11/11/14 St KI.14I31S ~l mil «muvnLis MO 0 At loumim no i tuursM CUTW> 1 1W IIHJI SOI 101 lis • MM sg nmsw UCMMM 4SI •tOMIHia sumuu oaraaii HTM ci tumt «l OCUUO 7M i no ­JL­ una •Jll [ t una IHM IsieaoMf iinu Ufotni Ml 104 Tj I OH IHIHI una mousiir srocu 1 I MO I , I/VI4 IIJOJ NONMUAl. • MI Mi ■'■MTDMI AIUM1HA 0 11 H)M| Hi M,ne«in • 111] AND (or BAUXITE U iW rj " j­j­ 771 otuouu KIT IKTMUTIOf nc ttunuo anar** cuiwonoa in 171 (rami uasas+ nccx&iw SMMI ions « AuninuM w« StC 111 1 i™ r~ i »o 4JUCTU TI MIHIH ~l 1S4I gin MT41 onm 111 m Ml (M MClUOIt MfTU WMWOO ffSOU IIOOI ^ lMI fe&iitL.iU room Muna 1011 • FUStO 0)1 of uumu actuns fwumi m putarmsii nmscaiM i eua 1110 ' 1 UlCMt ai ifunin ion nunc HUM* at uwiau ioa mease M:TU WOtIO tOIAl » MIUM amxm 11,400 — una** etroati — MUl a»0»TI aUtf.AU Of MINf I Ul MfAllMf NT Of MIHKM

­251­ Aluminum supply-demand relationships, 1965-74 (Thousand short tons, aluminum content) 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 World production (bauxite): United States 426 463 426 429 475 536 512 467 442 458 Rest of world —— 8,204 8,968 10.067 10.202 11,442 12.555 13.884 14,576 16.268 17.942 Total 8,630 9,431 10,493 10,631 Ilj917 13,091 14,396 15,043 16,710 '18,400 Components of U.S. supply: U.S. production: Mine: Intermediate products In• (384) 1*421) (381) (385) (420) (482) (452) (414) (384) (395) spects 1 grades 42 42 45 44 55 54 60 553 58 63 Alumina: Intermediate products \l- (2.632) (2.769) (2.824) (2.640) (3.045) (2.712) (2.744) (2.675) (2.817) (2,948) Speetal grades and for export 374 436 505 656 712 934 903 835 1,008 997 frlaary metal---—-— 2.754 2,968 3,269 3.255 3,793 3,976 3,925 4,122 4,529 4,903 Secondary— ——— 205 187 175 181 200 197 216 250 265 304 Shipments of Government stockpile excesses: Intermedlste products W--- (25) (8) (26) (53) (55) (218) (174) (84) (56) Hetal and special grades—- 49 378 70 68 149 26 6 735 550 Imports: Intermediate products 1/2/- (2.776) (2,992) (3.343) (3.469) (3,895) (4,371) (4,217) (4.309) (4.872) (5,439) Ketal and bauxite "il — 805 882 713 976 732 660 864 991 873 1,019 Industry stocks, Jan. 1: Intermediate products 1/- • (1.106) (1.138) (1.172) (1.130) (1,099) (962) (960) (1.019) (959) (962) Metel and special grade bauxite and alumina — 1.731 1,916 2.188 2.380 2.382 2,409 2.843 3.171 3.069 2,920 Total 5,960 6,809 6.965 7,560 8.023 8,276 8,811 9,428 10.537 10,756 Distribution of U.S. supply: Industry stocks, Dec. 31: Intermediate products 1/ (1,138) (1.172) (1,130) (1,099) (962) (960) (1.019) (959) (762) (818) Ketsl and special grade bauxite and alumina 1,916 2.188 2,380 2,382 2,409 2,843 3.171 3,069 2,920 3,508 Exports 557 531 654 803 1,086 1.165 847 794 1.110 1,026 Industrial demand —-— 3,480 4.090 3,931 4.375 4,328 4,268 4,793 5.565 6.507 6,222 Government accessions—-—- 7 U.S. demand pattern: Hetal: Construct Ion™—— 787 864 823 958 988 943 1 .193 1 ,461 1.543 1,335 Transportat ion———— 736 849 760 842 826 647 767 . 1 ,017 1.206 1,057 Electrical 444 566 533 559 593 570 609 701 798 796 Cans and contslners 269 322 371 437 497 615 648 539 884 986 Appliances and equipment 353 396 355 420 442 391 417 514 575 501 Machinery — 237 285 264 289 292 254 276 342 406 452 Other 280 395 434 468 447 332 311 377 371 322 Total 3,106 3.677 3,540 3,973 4,085 3,752 4 ,221 4 ,951 5,783 5,449 Ronmetal(alumlna and bauxite) Refractories— 135 136 148 121 134 136 141 174 245 255* Chemicals — 159 169 169 212 233 298 358 347 356 377 Abrasives— — 80 88 74 69 76 82 73 93 123 141 Total 374 413 391 402 443 516 572 614 724 . 773 Total U.S. industrial demand -.—.---—. 3.480 4j090 3,931 4,375 4,528 4,268 4 ,793 5 ,565 6,507 6.222 Total U.S. primary demand (Industrial demand less secondary supply) 3,275 3.903 3.756 4,194 4,328 4,071 4,377 5,315 6,242 5.918 Total U.S. demand for primary metal (metal demand less secondary supply) 2,901 3,490 3.363- 3.792 3,885 3.355 4.005 4.701 5.518 5.145 TfFigures in parentheses representing intermediate aluminum products (bauxite used In the United States to make alumina and alumina produced and Imported In the United States to make metal) are excluded from totals. il Bauxite and alumina. V Includes special grades of bauxite.

-252- BARIUM SUPPIY-DEMAND RELATIONSHIPS-1974

WOBID ftOCUCTION

Muacf anno IHHS 111 HI

wousm SIOCIS oi uo ew CAMOA mrcmis WUI UUUNT - 12/11/14 ■ousnits 10. 401 H4 so. 808 sic on uei ■OUSIfUU 71 as turn* US OEMAflO >rwi UUXO CFfMICAlS 111 174 154. mi ss SIC 2819 110 IXDUSTflY STOCKS flPOHIS fAMTS tjtia 1/1/14 —► 114. M 1) nit 90c i

Morocco 71 • UHfUTI SI sic sunMjto mousittiu. B.ASSIIC*IK»I isn mausuo SHOKI IC«S of IMIUM isti (BASSO 00 IMIII UWUMIW II rt«Cl«l IHl? tuncn (OU­vtuai IA­IIUHI 118 40

0IW« ill

WOtlO lOIAl US SUCCIAUOf MINIS 1.6S1. IM DCPAtlMENT OF I HI IMIUIOf.

Barium supply­demand relationships, 1963­74 (Thousand short tons barium content) 1/

1963 1966 1967 1968 1969 1970 1971 1972 1973 1974 World production: United States 474 564 529 519 603 478 462 507 619 619 Rest of world 1.709 1.714 1.673 1.591 1.769 1.951 1.842 1.935 2.048 2.063 Total 2,183 2,278 2.202 2,110 2,372 2,429 2,304 2,442 2,667 2,682 Components of U.S. supply: Domestic mines 474 564 529 519 603 478 462 507 619 619 Imports ­ 399 391 298 371 344 395 271 349 401 408 Estimated Industry stocks, Jan. 1 61 66 71 65 60 48 60 60 60 90 Total ­ ­ 934 1,021 898 955 1,007 921 793 916 1,080 1,117 Distribution of U.S. supply: Estimated industry stocks, Dec. 31 66 71 65 60 48 60 60 60 90 90 Exports 10 10 10 10 10 35 13 29 38 34 Industrial demand ­ 777 790 736 771 899 787 759 827 892 931 Apparent surplus (+), deficit (­) 2/ +81 +150 +87 4114 +50 +39 ­39 — +59 +62 U.S. demand pattern­ ~————^————~——~~■———~~~~~~~~~—— Oil and gas industries (drilling muds)— 570 573 S40 364 692 625 583 662 743 806 Industrial chemicals 105 113 95 98 99 81 79 59 61 58 Paints, plastics, and rubber 3/ 55 60 50 57 37 36 37 26 29 27 Ceramics and glass ­ 39 41 43 40 41 28 W W U V Other 8 3 8 12 30 17 58 80 59 40 Total U.S. primary demand— ­ 777 790 736 771 89! 787 759 827 (392 931

U Withheld to avoid disclosing individual company confidential data. 1./ Barium content of bsrte la aaaumed to be 567. regardless of source. 2> Indicates mainly grinding losses and changes In Industry stocks. 3/ 1971­74 Includes only paint; plastics and rubber Included In other. ­253­ BERYLLIUM SUPPLY­DEMAND RELATIONSHIPS­1974

woiuo rtoouciiON I ' . visa uwno tuns 72. w

«uaiA« AKSHfTSUS 1 until tiAClORS 1. •i ' ss. se 49ii IXOUSTIT STOUS MATH AIMS/ACf. MCOU », 11/31/14 4a 40. r 4Sf sic nil irei ■WASOA ', mot/sin ttoas us sumi US OfUAM IIKIKCU. 4. 1/1/14 m 701 so. * SIC 18 WWII iUC'fUMIC AUSHAIU », cc*tro

MY WOtlD TOTAL eowwMjiii siocmi k isiauiE lAUUKI U44f tC IIAHOATO HDUSTftUU nASSVICATBM IIBTl 720i UNT IHOF1 !0«S Of BffUIUW IfJil hUAUOT­IM » wmcmo io AVOIO osaosats HflAl R| UNfiOfariAi OAIA v tUIIAU OF MINES • i ifviuo US. OffAEtTMENT OF IMTIIIOR

Beryllium supply­demand relationships, 1965­74 (Short tons) 1/ 1963 1966 1967 1968 1969 1970 1971 1972 1973 1974 World production: United States W WWWWWWWWW Rest of world r 245 182 218 282 353 334 222 196 173 159 Total W W W W W W W U WW Components of U.S. supply: ' Domestic mines W WWWWWWWWW Shipments of Government stockpile excesses 136 166 83 9 109 19 Imports, metal 5 5 7 7 2 3 (2/) 6 Imports, beryl 312 86 380 153 257 198 161 134 ~65 55 Industry stocks, Jan. 1, 3/ W IJ W W V V V V I* W Total U.S. supply W WWWWWWWWW Distribution of U.S. supply: Industry stocks, Dec. 31,'3/— W WWWWWWWWW Exports, metal and alloy 60 31 38 47 15 20 21 48 55 72 Government accessions 38 3 171 —­ — Industrial demand 311 350 360 353 469 380 415 311 348 209 Apparent surplus (+) deficit (­) supply 4/ ­88 ­316 ­195 ­28 +5 ­27 +5 U.S. demand pattern: " ' ' Nuclear reaatora 124 150 131 38 53 40 50 70 90 55 Aerospace 112 137 42 38 55 30 55 76 75 45 Electrical 42 46 108 192 228 200 200 90 100 60 Electronic components 4 3 20 42 94 80 80 40 45 26 Other 29 14 59 43 37 30 30 35 38 23 Total U.S. demand 311 350 360 353 469 380 415 311 348 209 U Withheld to avoid disclosing individual company confidential data. 1/ Berylllua content of material classified as ores Is considered to be 4 percent. 2/ Less than 1/2 unit. 3/ Beryl ore. 4/ Total U.S. supply less yearend stocks, exports. Government accessions, and Induatrlal demand. Caused principally by inaccuracies in estimating beryllium content of ores and unreported changes in inventories.

­25I+­ BORON SUPPLY-DEMAND RtLATIONSHIPS-1974

WOtlD fBODUCnON I CERAI/ICS »«0 1 1 61ASS «S «S5« unto suns SIC 2279 40. NI C0A1MG AHO flAllHG nousim SIOCKS 10 Anuaiau TURKEY mown 11/11/74 SIC WIS n •0 I 10. AAtlOMIllRf 1 rioni s mruBtc os somr US OtMAKO Of CKWA SIC IS 19 70S s SCAIS AhO ortmciH'S I W0Us"i«Y SIOCM 1 1 I l/l/M SXKWIS SC 184 l_» 10 WOSID TOTAL I 5: IA3RICAIID A.ETAI 136. PRO axis 1 SC 1899 sc luxoARO wousiauu OASSiCAiioii OIHEI wtn IHOUSAKO SHOAI IOKS Of sows di 24

tUBEAU Of MINES US- MPAHTMENT OF INIEIIOI

Boron supply-demand relationships, 1965-74 (Short tons boron content)

1965 1966 196 7 1968 1969 19 70 1971 1972 1973 1974 World production: United States 132,175 143,682 147,103 161,409 171,361 175,000 176.500 189.000 207,000 19 3.000 Rest of world 57.100 65.400 73.500 70.300 79.741 82.400 10 7.200 125.000 135.000 135.000 Total 189,275 209,082 220.603 231,709 251.102 257,400 283.700 314,000 342,000 328,000 Components of U.S. supply: United States mines 132,175 143,682 147,103 161,409 171,361 175,000 176,500 189,000 207,000 19 3,000 Estimated imports 5.000 4,000 4,352 2.932 3,675 3.681 1,000 3,000 2,000 2,000 Industry stocks, Jan. 1 1.000 1.300 1.000 1.000 1.200 1.500 2.000 2.000 10 .000 10 .000 Total U.S. supply 138,175 148,982 152,455 165,341 176,236 180,181 179,500 194,000 219,000 205,000 Distribution of U.S. supply: Industry stocks, Dec. 31 1,000 1,000 1,000 1,200 1.300 2,000 2.000 2.000 10,000 10,000 Estimated exports 62.875 70,982 67,006 77,141 88,872 90.000 90.000 100,000 95,000 90,000 Industrial demand — 74,300 77.000 84,449 87,000 85,864 88,181 87,500 92,000 114,000 105.000 U.S. demand pattern: Ceramics and glass 22,200 23,100 25,335 29,200 29.194 30,000 35.000 37.000 50,000 45,000 Coating and plating (enamel) 10,360 10,780 11.823 11.900 12,021 12.300 8,800 10,000 11,000 10,000 Agriculture 10,360 10,780 11,823 11,900 12.021 12,300 8,700 9,000 8,000 7,000 Soaps and detergents 11,000 11,500 12,000 13,600 13.738 14,000 13,000 14,000 17,000 16,000 Fabricated metal products (fluxes) 1,460 1,540 1,689 1.700 1.717 2,000 2.000 2,000 3.000 3.000 Other 18,900 19,300 21,779 18.700 17,173 17,581 20.000 20,000 25,000 24,00C

Total U.S. primary demand 74,300 77,000 84,449 87,000 83,864 88,181 87,500 92,000 114.000 105.000

-255- CHROMIUM SUPPLY­DEMAND RELATIONSHIPS­1974 WOtlO flOOUCTION 1 1

MCMA IMIISO tuns nvuisfoaiAiaa ISO 0 mi iic J* MAIAGASST vssa 101 S4TOS11.0S1 coasisucitm nrusiic ASS. 121 HO S4 SK 14 MS MM RSHJSIC Of wroati Auors MACHMEtT SOUla AFRICA N SI -*. HI 90 140 ■cvstm STOCKS DJ/lkM sc » M ' Iff OIHEB lUfKIT •IPORIS fAMKAIEO HO 171 CHIMICAIS miAi raoouns -~ 2 40 lis sum* us MUAKO SC Ml ­H r IM 121 fHltfTMS M SICOKOAjn KiRACiasies 111 IS iirortis. Atiors M AM CKEMJCAIS SIC 1291 AISAWA > WDUSIIT S10CIS 1 HA1I»S Of 110. 1/1/14 UtlAlS 211 (irons ASO 11 MUTvUTV SC M7I 11 smfMUis or 11 B4DCSSIA CHEMICAU iioomt EXCESSES 110. •1 142 SC 211 *> l OlttfR •turn I •• 1 1 KIT maun WOtlO TOTAL tOTEMKENT STOuVU at siAHOAflo HDusiaui CIASSMATCM 1111 J.J30. am TMOUSAIO SHORI loss o» cmoHut* «» ­— ALIOT wroins — CKEKCAI mmwii •UtlAU Of MINIS US. Of f AITMENt Of INTEIIOI

Chromium supply­demand relationships, 1965­74 (Thoussnd short tons of chromium)

1963 1966 1967 1968 1969 1970 1971 1972 1973 1974

World production: United States Rest of world ­ 1 708 1 550 1 .635 1 736 1 814 2 ,030 2 184 2 184 2 ,386 2 .536 Total­ ­ 1 708 1 .350 1 .635 1 736 1 .814 2 C50 2 184 2 184 2 386 2 336 Components of U.S. supply: Domestic mines— —­• ­————— Secondary — — ———­ 43 49 43 45 61 58 63 52 53 63 Shipments of Government stockpile excesses­ 23 23 44 79 78 42 55 80 142 Imports, chromic, e ore 469 575 389 341 346 443 403 341 282 329 Imports, alloy —— — 38 66 39 42 44 26 34 92 113 107 Imports, chemicals 7 9 4 6 4 4 4 5 3 2 Industry stocks, Jan. 1—— ___— 405 372 429 406 328 256 269 382 338 239 Total U.S. supply 962 1,094 927 884 862 865 835 927 869 884 Distribution of U.S. supply: Industry stocks, Dec. 31 ——~ —­ 372 429 406 328 256 269 382 338 239 219 Exports, alloy and chemicals— — 9 6 10 20 19 21 7 11 16 ♦ Exporta, chroaite ore ­—————— 24 43 39 33 46 26 42 18 13 31 Industrial demand­— ——————— 557 614 472 503 541 549 404 560 601 623

U.S. demand pattern: Transportation — 86 97 75 80 90 90 BO 93 107 103 Construction—— 118 132 101 109 118 121 91 123 135 140 Machinery— _— 81 91 70 74 85 80 60 B6 90 90 Fabricated metal products­ 28 32 25 26 29 30 23 34 36 40 Refractories — 124 123 93 94 94 90 63 70 77 86 Plating of metals —— 13 15 13 15 16 16 14 18 18 17 Chemicals 31 46 42 47 49 48 39 32 55 61 Other 56 78 53 58 60 74 32 80 83

Total U.S. primary demand (Induatrlal de and leas secondary) 314 363 429 4SB 480 491 341 308 348 360

­256­ COPPER Wmr­OUMAND fELATIONSMtPS­Wa wotio rtooucnoN 1 "" 1 •veto mill I4K >u «« "ST ­­ •cons aincf ■vr ...cna. » ' m ^ « 11 ccmi«xie«

OKI notour muim itoai ­I r ""~" ..«««, IS" l« , , IRUB^II.IO. nXfrnnu 5i.!2£ limn ttiaco m L 0M«.C. ««,,

aftsin nous T ".i' «4

wu*M SIT sc­ si..u«g BOUSIM* amcotea ■immi aazu «t:l­ 1H0CAMS t*»\ t(M M W*. <■■ T ­c ­ ­ ­ C4IW0 C0m« MTOilf "S" ­'­J COMMMt.1 IIKftKt

• j •UtlAUOC HMI 1 n* atfAaiMm of fmrnoa wcMiei o At ejcs

Copper supply­demand relationships, 1963­74 (Thousand abort tons) 196) 1966 1967 1968 1969 1971 1972 1973 1974 Vorld production (primary): Mine production: United States­———­—— ■ 1,3)2 1.429 954 1,20) 1,343 1,720 1,522 1,66) 1,716 1,597 test of world——— — ­ 3,967 4,036 4,270 4,4)6 4,679 4,918 3,167 3,657 6,130 6,308 Totsl ­ 5,319 3,46) 5,224 5,641 6,224 6,6)8 6,689 7,322 7,848 8,10) Components of U.S. supply (primary and old scrap): Refined production: LVxteatic mines 1.1M 1.333 847 1,161 1,469 1,321 1,411 1.680 1.696 1.421 Old scrap 214 242 190 2)1 284 278 208 212 241 268 Imports of ore. Muter, etc 376 338 266 276 274 244 181 193 170 2)4 Shipments of Government stockpile .ic.ao.i ._— 120 400 149 — — 252 imports of r.fln.d :­ 1)7 164 Ml 400 1)1 132 164 192 202 314 Old scrap (unrefined) 299 29) 29) 290 291 226 2)7 246 243 213 Indu.tr? stocks, Jan. 1 467 496 402 507 36) 5*1 643 586 S17 436 Total U.S. supply 2,949 3.J08 2,698 2,86) 3.012 2.942 2,846 3,109 3,073 3,160 Distribution of U.S. supply: < Industry .tocka, Dec. 31 498 602 507, 36) 541 64) 386 517 4)6 S97 Export, (refined) )2J 27) 159 241 200 221 188 18) 189 127 Industrial demand 2,124 2.4)) 2.032 2.061 2,271 2,076 2,072 2,409 2,428 2,4)6 U.S. demand pattern: electrical 1,028 1,178 1,11) 1,046 1.193 1.101 1,11) 1,2)2 1,443 1,250 Construction 41) 410 277 )16 341 )28 331 4)2 355 425 Machinery M) 316 208 2)9 234 231 24) 300 2)) 340 Transportation 227 226 14J 191 196 17) 192 227 198 257 Ordnance 45 182 188 164 172 119 69 78 37 42 Other 106 121 101 10) 11) 104 104 120 120 122 Total U.S. industrial demand— 2.126 2.433 2.032 2.061 2,271 2,076 2,072 2.409 2.428 2,436 ­Total U.S. prlsary demand (Induatrlal demand less old scrap) !.*» '.»»• ».»*» >.»*» 1,496 1.372 1.627 1.931 1.942 1.93)

­257­ IRON ORE SUPPtV­OEMAND RtlATrONSHIPS­1974

WOaiD MODUCIION .—>—I . uamo S'Aiit in

IXIC CARADA JUL atnsn Ml 1S.I 11.4

ma nai/uiA L­. 41 in

•omul ISIfU II at 111 HAS! luvmas III luaofi v. Btun 1 IK 1111 ii ­ r- ■ S0.I ■ousim nous Acaouiwimc funis 401 in visa r Mil as aumt US 0EKAJIO " irfafu*fuas Ml is aAuanA** AUSIRAIH sic nil II 114 OIWCI Rioucia* WWII ruwis u U IS •auka _ swioia 11 741 OTWR • 1 04 j untiK o> lout* AffSCA ic ■ s. a urn mi M is

(IT an »a . fiietui if IC IIAS0AS0 mOUlIKUM aASUCAIOS anusiai siocis BMI anics SHoat lou of USIAWO »oan« fienis mfumc l/V/4 soil Bxta AM SIEH fiwaoni AM mauno m sc n OHM 411 ■ CMU il i. 111.

mam IMA 4»

WOtlD TOTAl S44 0. •UtlAU Of (MINES OS. OtfAttMIMT Of TM amUO*

Iron ore supply­demand relationships, 1965­74 (Hlllion short tons of contained Iron) 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 World production: United states­­—­­­­­­ 56.1 57.6 34.8 56.3 59.0 59.4 34.3 51.3 59.9 57.6 Rest of world­­­­—­— 306.2 322.3 320.2 372.0 389.0 418.1 434.1 435.2 484.2 508.4 Total— 362.3 379.9 375.0 428.3 448.0 477.5 488.4 486.7 544.1 566.0 Cienponenta of U.S. supply: Domestic mines 56.1 57.6 54.8 56.3 39.0 59.4 54.3 51.5 59.9 57.6 Imports 31.3 32.1 30.9 31.4 28.8 31.4 27.7 24.8 30.0 33.4 Industry stocks, Jan. 1 1/— 43.6 44.0 <­4.2 4S.9 47.6 44.6 47.2 53.0 46.0 41.5 Total ­ ­— 131.0 133.7 129.9 133.6 135.4 135.4 129.2 129.3 135.9 132.5 Distribution of U.S. supply. Industry stocks, Dec. 31 1/­ 44.0 44.4 46.1 47.6 44.6 47.3 53.0 46.0 41.5 40.1 Exports — 4.8 5.3 4.1 4.0 3.5 3.7 2.1 1.4 1.9 1.6 IX­oand 82.2 84.0 79.7 82.0 87.3 84.4 74.1 81.9 92.3 90.8 I'.S. demand pattern­ Blast furnaces 77.0 79.3 76.3 78.8 84.3 82.1 72.5 80.4 90.6 88.9 Steel furnaces 4.9 4.3 3.1 2.9 2.5 2.1 1.3 1.1 1.3 1.5 Other uses 0.3 0.4 0.3 0.3 0.3 0.2 0.3 0.4 0.4 0.4 Total— ­ 82.2 84.0 79.7 82.0 87.3 84.4 74.1 • 81.9 92.5 90.8 Total t'.S. demand 82.2 84.0 79.7 82.0 87.3 84.4 74.1 81.9 92.5 90.0 J/ l­igurea in parentheses sre negative. ­258­ LIME JUPPLY-DflMAND Rf LAIIONSHIPS-1974 WOtlD flODUCTION

rnssn UMfllD S1ATES 74 00C 71141

CXflflCAl A«3 Mf-AS CAKAtt sAJoai; aousuju 17112 4* BB3USIHT sioca nuo ll/lt/N SC 1119. 1112 ' 1.000 MSI HMAKT cossiiucicm 1 I2 1SI us sumi Ut MtAUO ' SIC Bll 35'« 11 en 11021 HHAHO MfaACion IIS U1J iiromi S< 111) L il HUWCf mousiRT nous A&acuuiw I/V14 IJCJ1 1000 Ml KIT MJsH aoxAaiA sc siAsaaio MDusiRui ausifCAitos loss •in ncousana SHOUT loss of list IUOI

llitum IMS

(Ml CEIB1MIT 1470

CrECHOStOVAMA 7110

0TK1R 21441

WOtlD TOTAL 121.640 8UKAU Of MINES Ul HPAtlMENT Of MTftlOt

Line supply-demand relationships, 1965-74 (Thousand short tons)

1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 World production: United States 16,794 18,057 17,985 18,637 20.209 19.747 19.591 20.290 21.132 21,545 Rest of world 66,389 68,013 71,761 75.373 79.087 86,921 90 J 98 92,233 97,065 99,995 Total 83,183 86,070 89,746 94,010 99.296 106.663 109.789 112.523 121f640 Components of U.S. supply: Domestic production 16,794 18,057 17,985 18,637 20,209 19.747 19,591 20,290 21,132 21,645 Imports 276 152 81 73 186 202 242 248 334 416 Industry stocks, Jan. 1 1,000 1,000 1.000 1.000 1.000 K00O 1.000 1.000 1.000 1.000 Total U.S. Supply 18,070 19.209 19,066 19,710 21,393 20,949 20,833 21,538 22,466 23,061 Distribution of U.S. supply: Induncry stocks, Dec. 31 1,000 1,000 1,000 1,000 1,000 1,000 1,000 1,000 1,000 1,000 Exports 40 60 52 69 51 54 66 38 37 32 Industrial demand 17,030 18,149 18,014 18,641 19,895 19,767 20,500 21.429 22,029 U.S. demand pattern: Chemical and industrial 13,160 14,245 14,527 15,173 16,764 16.870 17,181 17,702 18,428 19,180 Construction 1,477 1,512 1,433 1,422 1,532 1,51(3 1,499 1,586 1,611 1.463 Refractory 2,176 2,193 1,880 1,833 1,866 1,373 1,007 1.075 1,250 1.277 Agriculture --———_ 217 199 174 213 180 14? 80 3 37 140 109 Total U.S. demand 17.030~ 16.149 13,014 16.641 20,342 »,6?5 19.76) 20.500 21.429 22.1529

-259- LITHIUM SUPPLY­DEMAND RELATIONSHIPS­1974

wotto rtooucnofi 1 1 afUAIXS NO cuss 1200. S«f AIP3CA uanso sians DO w SC 122 PRIMARY AlUMOfUtt 1700. HHOOESIA tun it fMPOOTS SC 11M 2401 si 10 ujSKAars SOD. PIS REP Of OMSA 22 us sumr t'S DUAtRO 100, ii w 4S10I St 2392 A* Q3IDITXWSB ISO. USSR SHiPMiais cu 1 BHjnTS siocxni aassu l—— SC 1535 tmot 1020 • 430 onwi 110. 1 OIHIAS aratsueBiT STOOCPM SC2BK 1 »• ■AUMt C3A 411

• maun HC S1MCOKC SiaiSTnN CtASSf CAIfOft nrt siian low Of mmm m • (OVERMERI SlOMPIlf EICESS SMNIENTS ISAIESI «f IVI1MHE10 10 AYOU) OlSCtOSWC COOPASI toafuxaiiM OAIA

WOtlO TOTAL 6UIEAU OP MIMES US. OffAtTMENT Of INTERIOR

Lithium supply­demand relationships, 1968­74 (Short tons of lithium content)

1968 1969 1970 1971 H21 1973 1974 World production: United States W W W V V V W Rest of world 1,801,800 1.800 1,900 1,900 2,000 2,400 2,475 Components of U.S. supply: Domestic mines W W W W W W W Imports 220 40 30 130 30 130 70 Industrial stocks, Jan. 1 NA NA MA NA NA NA NA Shipments of government stockpile excesses —­ 160 430 Distribution of U.S. supply: Exports r/800 980 980 650 640 920 1.020 Industrial demand r/2,122,1200 2,220 2,680 3,150 3.280 3,850 4,530

U.S. demand pattern: Primary aluminum—~—­—— 200 300 700 950 1,050 1,400 1,700 Ceramics and glass 800 BOO 800 900 900 1,000 1,200 Lubricants r/400 400 420 440 460 480 500 Alt conditioning r/200 200 200 250 250 250 250 Other 520 520 560 610 620 720 880

Total U.S. primary demand— 2,120 2,220 2,680 3,150 3,280 3,850 4,530

tj Revised. NA Not available. W Withheld to avoid disclosing individual company confidential data.

­260­ WOtlD flODUCTION MAGNESIUM I ' 1 SUPPLY­DEMAND RELATIONSHIPS­1974 METAl IMT tsaris SIAIES TMatfoaiAicm a. • 44 SC 11

JAPAB ugucu i WWII BACHiaiaT 1 44 UJ • Bsusiar siocu Q/ll/14 SC IS w fftAKCf ana 4 iicaaucarc OfiasCAis , h i • US OEMMB I • 1 SVflf SX 111 121 •rousnrr nocu kOaflRROUS ian»AT • _J MfTAl PROOUCICm 424 1/1/14 n 1 upoars SIC I1J9 II •Hi ' SMPuonsof MM AM SIEI1 Ik siconi oassu fouaona 21 CI SIC 111 ■ TOTAL 140. acwRRdiai siccani uiKta *Auuaa . i u

MACNISIll

»CHCB10VAUA 110.

USSR AUSTRIA sipofnj 491. 101

CSflCi MOusrar STOOXS 1414 JT» r acRt«noMs 18 PiOPUS KPUSIC MOSTIrf ST0CU us tuppir III OfJAAao Of CMWA ion P I.OM ni. I CHSMCMS I BO TUtOSUWIA SK Ml Ml L 11 KIT tuatn or ma • Eiiaun 114. a wauMO ■ us PTOOUCTUS usou omossTL IEA WATEa. ASO SfEU vimts h. I PHStST IUT USKCMM TOTAL 1.934* t Atom 4i ptaaar MM SEA WATT* DOLOMITE. SEA WAIEI. AND Mil AKO IA(E SH»IS. AW SfTTHSI. ABO TM WELL AND LAKE MINES ■MAaioca ffos axoauTi KASMSITE. AMI OUMI SC. STAAOAftg ■OUStmAl CLASSIflUllON OTHER imnio STATU •Hi: ncouvuu SNOti TOU or MAGauui fatal ­ uoo IM

TOTAL 7,450 •UUAU Of MINES ULl D«f AJTAUNT Of INTtEIOC WORLD TOTAL S.S14.

­261­ Magnesium supply-demand relationships, 1965-74 (Thousand short tons, magnesium content) 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 World production: United States Nonmetsl 1,221 1,238 1,053 1,040 1,110 1,029 879 948 960 950 Metal 81 30 97 98 100 112 123 121 122 W Total 1.302 1,318 1,150 1.138 1,210 1.141 1.002 1,069 1,082 W Rest of world: Nonmetal 3,879 3,929 4,007 4,147 4,248 4,986 4,471 4,152 4,381 4,436 Metal 97 100 111 114 117 131 135 135 139 UP Total 3,976 4,029 4,118 4.261 4.365 5.117 4,606 4.287 4.520 A,576 Components of U.S. supply. ', U.S. production Nonmetal 1,221 1,238 1,053 1,040 1,110 1,029 879 94S 960 950 Primary metal 81 80 97 98 100 112 123 121 122 W Secondary metal (old scrap) 4 4 4 4 3 3 3 3 4 6 Shipments of Government stockpile excesses 2 17 7 1 26 15 1 6 27 21 Imports Nonmetal 50 112 77 79 66 84 95 87 115 106 Metal 3 3 9 4 4 3 4 4 3 5 Industry stocks (metal): Jan. 1- 17 16 11 13 10 13_ 13 15 23 19 Total U.S. supply 1,378 1,470 1,258 1,239 1,319 1,259 1,118 1,184 1,254 W Distribution of U.S. supply: Exports Konraetal 45 46 41 36 36 56 36 37 36 37 Metal 18 15 12 18 26 34 24 18 40 49 Industry stocks (metal): Dec. 31 16 11 13 10 13 13 15 20 19 W Industrial demand 1/ 1,299 1.398 1.192 1.175 1.244 1,156 1,043 1,109 1,159 1,148 U.S. demand pattern: ' Nonmetal Refractories 1,091 1,164 977 970 1,000 950 850 900 925 919 Chemicals 135 140 112 113 140 107 88 98 114 100 Total 1,226 1,304 1,089 1,083 1,140 1,057 938 998 1,039 1,019 Metal Transportation 29 37 40 36 40 40 40 43 42 44 Machinery 20 25 27 25 27 30 30 35 40 44 Chemicals 12 17 18 17 20 13 15 13 12 9 Nonferrous metal production 6 8 7 6 7 S 6 6 7 8 Iron and steel foundries 2 2 2 2 2 5 4 3 9 11 Other 4 5 9 6 8 4 10 9 10 13 Total 73 94 103 92 104 99 105 111 120 129 Total U.S. industrial demand 1,299 1,398 1,192 1.175 1.244 1,156 1.043 1.109 1.159 1,148

Total U.S. primary demand 2/ 1.295 1,394 1,188 1,171 1,241 1,153 1.040 1,106 1,155 1,142 Total U.S. demand for primary metal 3/ 69 90 99 88 101 96 102 108 116 123 W Withheld to svoid disclosing individual company confidential data. 1/ Sum of total nonmetal and total metal demand. il Total U.S. demand less U.S. recovery.from secondary metal. 3/ U.S. demand for metal less U.S. recovery from secondary metal.

-262 - MANGANESE WOtlO MODWCTIOM fUmV­MMUND RHATtONSMIfS­1974

MB1I* lUIU

>l»il I u­nt.at XTimu ""Tf •mf tcVll 1 1 UMWMtkiM 1 *«" U II 1 1 ""ST" W H ^? «•><■•»* itaca 1 an. ­­­J­­H r lit "H I T.~ ft/tluUCII MO 1 " "I'ST" "".T" T "TLST lit ill """S" ACWit.ill T, ­5­J I it mn in I i CiWf> *U4» M«AU aMOtm irtcn > "»•" M K ­­«*{ I "J"' i i •at ttM»AM MUB'«3*| CUUSafaUtCa * «ctiH>tB raoauM ICIUI M 111) *" •Wt IrOuiAM IM«I IB4TI » iAMMHU Mssj — — " .ttjUKAsHU a t «M MPWIS . » ««c. ..­.j i ntoni uxuiti

I autiAU OP am mi. atraaiAtMi cr­ smnoe

woaie IOIAI W.ISO

Hanganeas supply­demand relationships, 1965­1974 (Thousand short tons, manganese content)

1965 1966 1967 1968 1969 1970 1971 1972 1971 1974 World production! United Stateo 83 88 73 48 93 66 38 29 31 35 Rest of vorld 8.717 8.893 8.205 8.549 9.192 8.978 9.960 9.983 10.707 10.185 Total 8.800 8.981 8.278 8.597 9.285 9.044 9.998 10.012 10.738 10.220 Components of U.S. supply: Dom.se lc mines 83 88 73 48 93 66 38 29 31 33 Shipment of Covernuent stockpile excesses ­101 ­53 32 73 50 140 118 218 242 607 Imports, ore 1,221 1.223 978 870 992 847 938 793 722 593 Imports, alloy and metal 211 221 193 181 257 218 212 305 336 376 Industry stocks, Jan. I 948 977 1.093 1.171 1.180 1.241 1.173 1.281 1.241 978 Total U.S. supply 2.362 2,456 2,389 2,345 2,572 2,532 2,481 2,626 2,572 2,789 Distribution of U.S. supply: Industry stocks, Dec. 31 977 1,093 1,171 1,180 1.241 1,175 1,281 1,241 978 1,183 Exports, ore 7 8 8 10 10 10 25 12 29 107 Exports, alloy and metal 5 2 3 5 4 20 5 7 11 7 Demand 1.373 1.353 1.207 1.150 1.317 1.327 1.170 1.366 1.354 1.492 U.S. demand pattern: Conatructlon 268 282 254 276 268 260 252 236 325 317 Transportation 273 276 243 273 253 226 261 239 340 315 Machinery 186 196 175 198 185 176 175 171 229 245 Cans and containers 67 62 59 72 62 73 71 38 72 79 Appliances 4 equipment 46 51 49 53 51 51 51 51 68 68 011 4 gas industries 40 51 39 52 43 42 46 44 63 69 Chemicals 50 62 59 59 37 37 35 50 34 65 Batteries 12 18 15 15 20 20 19 18 IS 18 Other 1/ 431 335 314 152 398 442 260 499 385 316 Totsl U.S. primary demand­ 1,373 1,353 1,207 1,150 1,317 1,327 1,170 1,366 I75~54 1,492

1/ Includes processing losses.

­263 ­ WOtlO PRODUCTION NICKEL SUPPLY-DEMAND RELATIONSHIPS-1974

POUtO ISSTIO S1AIES 049SLMS II Ml 410 SC II fAfUCAHD aaXMSiA AUST1MU4 •47WTJ. PttSUUTT IKIAI. mourn 710 44 1 2201 in SC M CUBA SOUTH AFSCA itujOPomAnoa ISO 211 SII ' MOUSTRT STOCKS T2/1I/M SC 11 111. UWTBOISOOM siamrjaTf CUCTRCAl 14 1, 144 US SUPPM SC 261: . IIS 2 - ". ■OJSTRT SIOCXI < MOUSWAC 1/1/14 AfniAoas 111. WORTS in UC 111 sxnuais Of 414 sioupiifficfsas tAACKMRT 110 4t SC IS BMUUDOTA COXSTSUCTM M2I IIS i SC 144 ■ niMXEUM 211 scnii OHM MY lie aESTUATI GREECE sc nAtcMiD KDUSTTUAI ctAsssCAm 1*07 THOvOAffO SNORT 10*3 Of SOU W 211

CEPueut 110 6UIEAU Of MINES It*. DEP*ARTMSNI OE THE INTEMOI USSR as a

OTHER III n

WOtlD TOTAL 023.2.

-261, _ Nickel supply-demand relationships 1965-74 (Thousand tons)

1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 World mine production: United States 13.5 13.2 14.6 15.2 15.8 15.6 15.6 15.7 13.9 14.1 Rest of world 454.fl 426.9 480.2 532.9 516.9 676.8 68S.0 666.2 707.7 609.1 Total 468.3 440.1 494.8 543.1 532.7 692.4 700.6 631.9 "721.6 823.2 Components of U.S. supply: Domestic mines 13.5 13.2 14.6 15.2 15.8 15.6 15.6 15.7 13.9 14.1 Secondary 51.4 63.1 52.3 36.6 71.0 48.7 63.1 67.5 65.9 64.5 Shipments of Government stockpile excesses 16.3 103.6 23.3 3.2 4.3 2.1 14.9 1.8 1.0 4.6 Imports 163.0 141.0 142.6 143.7 125.8 156.3 142.2 173.9 191.1 220.7 Industry stock, Jan. 1 17.2 14.1 44.5 39.6 37.2 31.9 24.7 57.3 77.9 71.3 Total U.S. supply 261.4 335.0 277.3 238.3 254.1 254.6 260.5 316.2 349.8 375.2 Distribution of U.S. supply: Industry stock, Dec. 31 14.C 31.3 34.6 37.3 31.9 24.7 57.3 77.9 71.3 87.3 S.6 11.8 8.0 6.5 1.4 6.5 4.6 3.0 5.0 4.3 Industrial demand— ——— 241.8 291.9 2 34.7 194.5 220.8 223.4 198.6 235.3 273.5 283.6 U.S. demand pattern: Chemicals— —————— 16.8 21.4 25.9 21.9 34.0 33.4 29.7 35.2 41.2 43.0 Pet roleum 9.1 11.7 14.1 11.9 17.0 17.8 17.9 21.3 24.7 26.1 Fabricated metal products -— 22.5 28.7 40.2 24.5 18.4 21.3 20.3 23.6 27.5 26.1 Transportat ion: Aircraft 23.9 30.4 16.5 24.2 14.8 13.4 13.9 16.2 19.2 17.0 Motor vehicles and equipment •—___• 38.4 36.6 23.9 22.0 23.3 26.7 21.8 26.4 30.2 29.4 Ship and boat building and repairs 9.1 11.7 7.3 9.1 8.5 6.6 6.1 6.8 8.4 13.4 Total 71.4 78.5 47.7 55.3 46.6 46.7 41.8 49.4 57.8 59.8 Electrical 28.5 34.7 20.2 20.2 29.7 28.8 25.7 30.6 35.6 34.4 Household appliances 24.9 28.9 18.4 18.2 13.4 14.5 13.6 16.5 19.2 21.7 Machinery 33.6 42.6 12.9 12.6 16.0 16.5 13.7 16.5 19.2 23.0 Construction 9.8 13.8 11.0 10.3 15.8 21.3 17.9 21.3 24.7 28.5 Other 25.2 31.6 44.3 19.6 29.9 23.1 18.0 20.9 23.6 21.0 Total U.S. primary demand 1/— 190.4 228.8 182.4 157.9 ~49.8 174.7 135.5 167.8 207.6 219.1 1/ Industrial demand less secondary.

-265 POTASH WOtlD PRODUCTION SUPPLY­DEMAND RELATIONSHIPS­1974 I L »

tAST GERMANY INITIO STATES 2SS2

flARCt USSR 7S IMPORTS stousror sToas 1100. U71V74 ISM 4.121 2n •S1KW.TURI 1112 CAKADA 4*4 us sumr sfAia US C49UX0 sr 211 141 • 012 1014 • Oil , CHEMICALS 214 HOPII s atpvauc WIS! EERMMT 10 auxsnn siccus aroiil t/l/14 Of CMMA 2 Ml ill us. 201

coaco [ BRAll •1 OMu'lAVmil •60. ISO. KIT • ISTMATt nut OTKM 41 SC ITAItOAfai MOUSTNAl aASSfKATIO* 210> 0

P01ASSIUH SOOU4 HI1AAIIS AM POTASSIUM CHtt IUIAII 7*.

WOttlO TOTAl I6.04S* BUtlAU Of MINES VI MPAttMENT Of THE INTEMOt

Potash supply­demand relationships, 1965­74 (Thoussnd short tons of KjO)

1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 World production: United States 3,140 3,320 3,299 2.722 2.804 2.729 2,587 2.659 2,603 2,552 test of world — 12.060 12,739 14,054 15,145 16.394 17.284 19,358 19,401 21,695 23.516 Total 15.200 16.039 17.353 17.867 19.198 20.013 21,945 22,060 24,298 26.068 Components of U.S. supply: Domestic mines 3.140 3,320 3,299 2.722 2,804 2,729 2,587 2.659 2,603 2,552 Imports 1.108 1,491 1.708 2,166 2,332 2,605 2,766 2,961 3,587 4,326 Industry stocks, Jan. 1——— • 295 504 690 863 676 392 454 428 468 206 Total U.S. supply 4.543 5.313 5.697 5,751 3.812 3,726 5,607 6.048 6.658 7,084 Distribution of U.S. supply: Industry stocks, Dec. 31 ■ 504 690 863 676 392 454 428 468 206 211 Exports 648 621 693 735 700 544 564 764 889 787 Demand —­— • 3.391 4.004 4.141 4.340 4.720 4.728 4.815 4.816 5.563 6.086 D.S. demand pattern: ART Icul ture • 3,174 3,771 3.913 4.101 4.490 4,516 4.566 4,538 5.261 5.792 Chemicals 217 233 228 239 230 212 249 278 302 294 Total U.S. primary demand— ■ 3.391 4,004 4,141 4.340 4,720 4,728 4.815 4.816 5.563 6.086

­266­ RARE EARTH ELEMENTS AND YTTRIUM SUPPLY­DEMAND RELATIONSHIPS­1974

WOtlD PIOOUCTION , I

AUSTRALIA utnio STATES 2W2. 22 4l2t PSlKAfUM • 100. ■ousiar sicccs •ULMI1AMA ; •SAB. 112. rntfom 12/11/14 SC 29H 901. IWtt ! 1.114 CtlAMCS MO GIAS1 2 <00« MH atou 7M., atousiRT STOCKS Ul nSUPPIT US OEMAae 1/1/14 IS* 1.131. M4I4 ■ MM. ! 4101 ROa MO SIEEl fOuaoRKS j MAUrSH 141 SHIPME SIS TST^ S100. 1104, STottrii ntssss 40SO. ; 2 SSI /

; IKA1AM US I »4>

j • SSI », 2000. I KIT • ISISMTI ; 11. tc STMOARO auusrau CUSWCATRM • 1. m/ummm va •MT SHOtr loss or A/us IASTH ifaxiuoais rnftuMi em rmoi : 1i lALAlia

fHAfia 12 !

• OTMU a Ti.

tUISAU Of MINIS WOtlD TOTAL Ul OWAtTMtNT Of INTCtlOt H.4fv»

tLare­earth elements (including yttrium) supply­demand relationships, 1965­74 (Short tons of rare­esrth oxides (RIO)) 1965 1966 1967 1968 1969 1970 1971 1972~ 1973 1974 World production: United States e/ V WVVWHVV 20,209 22,482 Rest of world e/ V W W W W W W W 9,650 9,017 Total e/ 9.844 17,800 22,115 19.941 24,209 20,961 21,280 23,561 29,859 31,499 Components of U.S. supply: Domestic mines V VVVWHVV 20,209 22,482 Shipments of Government stockpile excesses 38 756 1,517 184 1,496 . 24 140 2,553 Imports, compounds and metal 440 440 430 490 363 380 786 1,019 740 670 Imports, monazlte and other raw materials 1,143 1,389 1,230 2,452 2,412 1,989 1,939 539 1.198 726 Industry stocks, Jan. 1 W WVWWVVV 4,096 4,103 Total U.S. supply 18,903 23,843 20,931 21,623 26,625 20,357 19,125 21,559 26,383 30,484 Distribution of U.S. supply: Industry stocks, Dec. 31 V V V W V V V 4,096 4,103 8,934 Exports, concentrate, compounds and metal 1,826 1,726 2,563 2,902 3,003 2,271 2,526 2,501 5,980 6,050 Government accessions 9 —­ —— Industrial demand 5,570 7,300 6,100 8,600 11,100 11,600 10,300 13,500 16,300 15,500 Apparent surplus (+), deficit (­) supply 1/ +2.914 +9,702 +6,707 ­2.466 +6.033 +3.261 ­1,079 +1.462 U.S. demand pattern: Petroleum refining (catalyst)— 2,300 3,600 3,000 3,230 6,800 5,200 4,080 4,430 6,900 6,800 Ceramics and glass 1,600 1,930 1,500 1,650 2,300 3,570 2,650 2,270 2,800 2,600 Iron and ateel foundiies 900 1.000 850 920 1,130 1,720 2,750 5,900 5,700 5,300 Other 2/ 570 770 750 780 870 1,110 820 900 900 800 Total U.S. industrial demand­ 5,570 7,300 6,100 8,600 11,100 11,600 10.300 13,500~ 16,300 15,500 if Withheld to avoid disclosing individual company confidential data. • / Estimated. XI Mainly partially processed materials, not reported as stocks. 21 Electrical, nuclear, carbon products, crystal, cathode ray tubes, research and development.

­267­ SALT SUPPLY-DEMAND KELATIONSHIPS-W74 woaio ptoouciiOH I tortil atnimc aamo SIAIII meat • 4|« am 4*411 Mills alia uuu 111! atroms 1 PAPIR mocuni II mi SIM 1». \ 4KI

•III

AUSIRMIA a, mniii nooutioa • 110 BC SIAJKNMI mnrsiaAi cuiwcAioa ma, faouSAaa taasi last at IAII CilROtlUM PSIASO 1*11 amain

IAM14ICSJ K»*> ancll • ni WOIIO TOTAl ua.»i4 IUIIAU OP SUMS US. PSPAtlfSSNI OP IMS etTtsKM

Salt supply-demand relationships, 1963-74 (Thousand short tons)

1965 1966 1967 1968 1969 1970 19 71 1972 1973 19 74 World production: United States 1/34,687 1/36,463 1/38.946 1/41,274 1/44,245 46,764 44,700 44.010 44,298 46,423 lest of world s/ — 85.04S 85.811 92.146 97.152 106.250 114.317 114.407 118.931 121.228 122.511 119,730 122,274 131,092 138.426 161,081 159,107 162,941 165,526 168,934 s/ 150.495 Components of U.S. supplyi Domestic sources — 1/34,687 1/36,463 1/38,946 1/41.274 1/44,245 46,764 44,700 44,010 44.298 46,423 2,410 2,479 2,843 3.456 3,302 3.536 3,835 3,463 3,187 3,358 Industry stocks, Jan. 1 940 985 1.050 1.185 1.185 1A270 2.540 2.540 2.9 70 2.970 Total U.S. aupply 38,037 39,927 42.839 45,915 48,732 51.570 51,095 50,013 30,455 52.751 Distribution of U.S. supply: Industry stocks, Dec. 31 985 1,030 1.183 1,185 1,270 2,540 2.340 2,970 2,970 3,076 Exports— —_- 688 662 678 728 716 423 670 869 609 521 Industrlsl demand 36,364 38,215 40.976 44,002 46,746 48,607 47,885 46.174 46,876 49,154 O.S. demand pattern: e/ 4.975 4,494 3.669 6,131 7,510 8.536 8,730 9,894 6.729 8,426 8,789 8,656 9.172 9.9 74 10,843 10.612 9,704 9,615 10,665 11,000 Paper producta ——— 2,843 3.193 3,246 3.537 3.802 4.230 3,824 3.795 4,059 4,008 Ceramics and glass — 3,554 3.784 3.697 3.773 3,732 3.848 3,683 3.445 3,194 3.089 Paod producta — —-— 2,724 2,649 2,820 2.830 2,723 3,059 3,400 1,376 3,442 3.418 Plastics sod synthetics- 2,037 2.247 2,346 2.338 2,699 3,107 2,810 2.910 3,174 3.177 agricultural chemlcala 2.037 2.034 2,180 2.334 2,347 2,677 2,621 2.607 2,808 2,670 2,085 2.294 2,299 2.358 2,441 2,629 2.479 2,421 2,432 2,421 1,279 1,466 1.517 1.580 1,643 1,864 1.633 1,723 1,843 1,868 W«e«r and ••mltary service- 948 1,017 1,138 1,297 1.314 1,291 1,204 1.234 1,267 1,414 995 1,017 1,114 1,085 1.197 1,362 1,228 1.304 1,433 1,470 4,098 3.364 5,758 6,745 6.493 5,372 6,709 3,850 5,808 6,193

Total U.S. primary demand 36,364 38,215 40,976 44.002 46.746 48,607 47,885 46,174 46,876 49,154 tJ Satlmats. XI Total used sad sold; true production mot available.

-268- SODA ASH SUPPLY­DEMAND RELATIONSHIPS­1974

WOtlO PtOOUCTION I tlASS 7104 una OalTEO IIATU SC 11 4IM I Ml ' CMMCAiS 1.1S BHUSIOT S10CU 4RPAS nuact avoais I2/1W4 SC 201 ISM 1.724 IS 78 PUP aao PAPta 4 IS POUUIO US luPPVr US BUASB SC 2311 120 INI 'lltl onEnscais IIS •fOUSIRY IT0O3 BAIT MSI URUMIT aram 1/1/14 SlC 7)41 no ISIO sea art WAIIR — IRSAlWial 210 Kiuua alTHiaLAMS SC 3SII 110 440 O'SIR Ull iniTIO IBfJOOM KIT • A a ESTIMATE sc tTAsoAao auusiaiAi CLASSSCAIICS •art iftousjwo sacMT TOSS OP IOOA AS* tUMARIA ■A KIT MAKAOU ISO

9THER 17J4

WOCLD TOTAL 1UIEAU Of AAINCS US. MPAIIMENT O* INTUIOt

Soda ash supply­demand relationships, 1963­74 (Thousand short tons)

1965 1966 1967 1968 1969 19 70 1971 19 72 19 73 1974 World production: United States 6,420 6,809 6,575 6,639 7,035 7,071 7.163 7,528 7,535 7, 561 Rest of world e/ 10.655 11^051 11,526 12_,288 13.205 14,020 14.846 15.095 15.763 16, 358 Total e/­ 17,075 17,869 18,101 18,927 20,240 21,091 22,009 22,623 23,298 23,919 Components of U.S. supply: Domestic sources ­­­­­­­­­­­­­ 6.420 6,809 6,575 6,639 7,035 7,071 7.163 7,528 7,535 7,561 Imports ­— —— ...... — ... 16 35 Industry stocks, Jan. 1­­­­­­ 644 421 336 206 74 178 148 115 92 105 Total U.S. supply 7,064 7,230 6,911 6,845 7,109 7,249 7,311 7,643 7,643 7,701 Distribution of U.S. supply: Industry stocks, Dec. 31 . 421 336 206 74 178 148 115 92 105 79 Exports 277 346 304 288 324 336 437 480 425 564 Industrial demand— 6,366 6,548 6,401 6.483 6,607 6,765 6,759 7,071 7,113 7,058 U.S. demand pattern: ej Class production — 2,546 2,685 2,689 2,593 2,843 3,180 3,109 3,465 3,628 2,900 Chemical 1,528 1,638 1,536 1,621 1,586 1,623 1,554 1,697 1,778 1.825 Pulp and paper­­— — 573 324 576 584 528 541 405 495 498 475 Water treatment­­ 254 196 257 195 199 203 203 212 214 220 Detergents cleaners­™­­­— 319 327 256 259 331 271 338 424 356 375 Other — 1,146 1,178 1,087 1,231 1.120 947 1,150 778 639 1.263

Total U.S. primary demand— 6,366 6,548 6,401 6,483 6.607 6.765 6,759 7,071 7,113 7,058 e/ Estimate.

­ 269 " STRONTIUM SUPPLY-DEMAND RELATIONSHIPS-1974

tllCTRWIC coaaxmarrs WOtlO PRODUCTION ISOO. 1 PTWTEOUIC r 1 MATIRUIS 4 400, AinaiA wine STATU 1000. 0 a;cnaCAi 21004 SltR mxa 11100 SAPtJRTS SKUsTrrr STOCKS 0/21/74 1000. 11000 22 000 1000. CfRAMCS AKO GLASS n (00. MGtsiaw CANADA 4J00 • I SUPfvT OS OffAASO SC 121 soo. 20 0C0 11100. 19100. aMfffMXB ISTAl PHOOUCIiOS acousntt STOCKS too. DMTEO UBSSOSI SPAM 1100 I/V74 lit 1.500. 10M 4 000. lUSiaCMIt • UTMATI SKTVEIITSOf 400. OTMa 100 sc HAMMMI WOUSTMU. CUSSPCATIM STOCKPU BUSSES ism stroll TOSS of snoanum pvt SC 2911 TOO 1.100 Plans ! | •04 1 w< IAI >tlD TO tovisBMtiT iToani 49.000. 1000. 6tltF.AU OF MINIS US. MPAtTMINT OF INTEtlOt

Strontium supply-demand relationships, 1965-1974 (Short tons strlntlua content)

1965 1966 1967 1968 1969 1970 1971 1972 1973 1974

World production: United States -———...... Rest of world----- — 7.890 9.260 6.143 9.373 15.681 27.421 45.186 42.542 42.200 49.000 Total 7-890 9,260 6,143 9.373 15.681 27.421 45.186 42.542 42,200 49.000 Components of U.S. supply: Shipments of Government stockpile excesses------+1,172 +1,392 +5,485 +1.708 +1,800 Imports ...... 4,413 5,490 2,542 5.842 12,595 16,876 20,169 13.536 16,300 22,000 Industry stocks, Jan. 1—------1.332 1.505 2.523 1.627 3.186 5.441 4.90O 5.209 4.000 4.000 Total 5,745 6.995 6,237 8.861 21,266 24,025 25,069 18,745 20,300 27,800 Distribution of U.S. supply: Industry stocks, Dec. 31------1,505 2,523 1,627 3,186 5,441 4,900 5,209 4,000 4,000 8.000 Deovand—------— --.-.--.-. 4.240 4.472 4.610 5.675 15.825 19.125 19.860 14.745 16.300 19.300 U.S. demand pattern: ...... Electronic components-----—-— 8,400 9,500 9.600 7.000 8,000 9,500 Pyrotechnic materials 2,100 2.300 2,400 3,400 3,500 4,600 5,000 3,200 2,400 4,400 Electrical ... 1.500 2,500 2,700 2,000 2,600 2,800 Ceramics and glass — 400 423 450 500 550. 650 650 650 700 800 Monferrous metal production— 600 600 600 600 600 600 600 600 600 600 I.uhr leants------100 100 , 100 100 100 100 100 100 100 400 Paints 40 47 60 75 75 75 75 75 100 160 Other 1.000 1.000 1,000 1.000 1.100 1.100 1.135 1.120 1.800 940 Total U.S. primary demand—— 4,2c»0 4,472 4,610 5,675 15,825 19,125 19.860 14,745 16,300 19,800

-270- TIN SUmV­OtftlAM) ttlATIONSMPS­l<774 oceiD paooucnoM

'""

IX nn avont am ]­ sttBST*' 110011 LIB r

moipu fxau an.­ «»»

KIT WC |I*­*(VJ0 MMTihAt IM IMS TWO * TsU (9M • TWTH«(B 18 MM) Mai

fUPvn Knauc !?V4 o CMU » MmM IIIHM • ­• mm m ma SUA JSVHI ina. ainta .fj Ull

WOMD IOTM" HJKAVOf MUMS

Tin supply­da And relationships, 1963­74 (Long tool)

1963 1966 1969 1973 Vorld production: United Statee— 47 97 fceat of vorld— 201,068 207.974 214,233 228,332 225,725 228,500 232,232 240,331 232,358 227,642 Total­ 201,115 208,071 CoapoQenra of U.S. supply} Saelter production 3,098 3,823 3,048 3,453 343 a/4,667 a/4,000 a/4,266 a/4,848 a/3,927 Shlpaentr of Cove nnnent stockpile exceeeee­ 21,733 16,276 6.146 3,308 1,700 3,065 1.736 233 14,652 23.469 fecoodary (old acrap) 1). 009 15,332 13,460 13,427 11.671 11.892 11.276 11.220 11,686 11,342 Importa for cooauaptlon (metal) 40,816 41.699 30,223 )7.338 34,930 50,))4 46.940 52..SI 43.84) 39.602 Industry stocks, Jan. 1 35.761 39,412 34.398 31.422 10,519 24,731 22,810 20,32/ 21,63) 20,346 Total U.S. supply­ 116,417 116.564 107,473 109.168 101,183 94,909 86,762 88,497 103,686 100,886 Ma trlbut Ion of U.S. supply: Industry stocks, Dec. 31—— 39,412 34,598 31,422 30,519 24,731 22.810 20.327 21.63) 20.346 35,084 Ivports, natal ——— 2,829 2.847 2,479 4,493 2,903 4,432 2,262 1.134 3,406 8,413 Induatrlal deaaod———— 73,899 7),46) 71,431 72,893 71,686 6),728 61,130 60,241 63,849 57.387 Apparent surplus (+), deficit (­) »up?ly ♦:77 +3.654 +2,143 +1,261 ♦1,863 ♦1.919 ♦3,04) +3.467 ♦14,085 .S. demand pattarnt Can* and containers—— 28.062 26.744 27,429 26,942 23,034 23.435 22.186 20,091 20,766 21,197 Tranaportatloo 8,722 9.087 7.631 8,509 8,389 7,888 7.M> 8,127 9.358 6,574 Machinery — 7,474 8.071 7,336 7,845 8,288 7,319 t.322 6.395 7,492 6.331 Electrical 11,373 12.183 11.977 12,246 12,491 11.072 10.410 10,239 11,472 8,261 Construction—■ — 12.303 13,366 11.208 11,043 11,441 10,319 8,995 9,004 9.312 7.816 2.833 2.830 2.793 3.190 3.132 3,146 3,670 4,0)3 4,8)7 4,891 Other 2,932 3.184 2.817 3,118 2.911 2,549 2.010 2,132 2.197 2,117 Total U.S. induatrlal demand 73,899 75,465 71,431 72,893 71,686 65,728 61,130 60,241 65,849 57.387 Total U.S. primary datund (Induatrlal de*caod leas aecocJary) ­­­­­­ —.—■——.­ 58,690 60,113 57.971 59,466 58,013 53,836 49,834 49,021 54,163 43,843 Eatloatcd. Withheld to avoid dlecloalne, Individual company confidential data.

­ 271­ TITANIUM SUPflTDCAAANO tfl ATiONJHIM­1974 woaio ptoovcnoH I ' 1

U1IH a

masm noas Tj ­HTB­ I (CMMMfai STQCUli rnaau ocaua I

eame SIAUI PAsrci MI m ami fU nPHfaoncii 4I» *n\ mi II HH ft It ■nam icocis nAsro wo "IT r mucTtisacjLcn •vauin STOCKS un aiauuae ajaaiR noaucii 41 441 IH

aw a w L ocnni S5i*** WB T tmm twfmm Klim) tn­tt M MUM » k naajiTi aim t u m maaxm* MTU ■ i«t at IOTA! 1.111 • aanviie II AVOW eucumaa CSSHST caafsuiw aau

woeto IOIAI VMS auaiAu OPSUMI an. ctMaiawn OP scntiot

Titanium eupply­dcmand ra latlonshlpa, 1963­74 (Thouaand ahort tone Itanium content) 1963 1966 1967 1968 1969 1970 1971 1972 1973 1974 World production (llmenlte and rutllc): United Statea —­ 304 302 29) 312 28) 276 224 228 286 2)7 teat of world .——. ­­ 893 975 1,050 1.124 1.281 1.498 1.397 1.384 1.404 1.331 Total '.19* 1.277 1.343 1.436 1.566 1.774 1.621 1.612 1,690 1,588 Coaponenta of O.S. aupply: DocBcst ic alnee— ­ 304 302 29) 112 283 276 224 228 286 2)7 10 V Shipments of Covsrnment atockpll. exceaeea­ 1 1 10 1) 184 190 196 204 200 269 224 296 353 288 loduatry atocka, Jan. 1— — 425 463 492 322 54) 510 528 467 346 33) Total U.S. aupply ■ 913 936 984 1,038 1,028 1 .0)3 976 991 1 ,003 1/89) Distribution of U.S. aupply: Industry atocka. Dec. 31 • — 46) 492 322 34) 310 328 467 346 33) 2SS 16 16 16 19 17 22 18 11 2) 20 Covernment acc.aa lona — 2 1 7 2 2 444 463 4)2 486 S3) 490 488 611 64) 5*8 Apparent aurplua (+), deficit <­) aupply _ ­10 ­13 ­12 ­33 ♦8 ♦3 ♦23 O.S. demand pattern: ­* — Hoocaetal: 22* 240 238 254 266 263 2)1 300 312 28) Paper producta 61 71 71 79 96 7) 91 12) 137 101 Mastlce and synthetic products­ 37 40 38 47 49 41 3) 4) 58 61 Rubber producta 20 20 1) 14 14 1) 14 19 22 13 Ccraalce and glaae 8 » 9 11 12 10 11 14 17 14 13 14 12 12 13 11 10 10 12 11 Other 61 47 46 49 38 51 61 81 57 69 Total 429 441 427 468 508 466 471 392 61) 556 Metal: Transportation equipment 11 20 24 17 24 21 13 16 26 26 Fabricated metal producta 2 2 1 1 3 3 4 3 4 6 Total 15 22 25 18 27 24 17 19 30 32 Total U.S. demand 444 463 452 486 )35 490 488 611 64 5 388 Total U.S. primary demand 452 486 535 490 611 635 Withheld to av­'id diacloattig individual conpany coni ldentlal data. I' Excludrhr ItearJamea mmr.tnAaecondar at a­yw ­272­ WOtlO PtOOUCIION ZINC I « 1 SUPPLY-tXMANO RELATIONSHIPS-IVM

aOMASIA UmlUO SIAfts US lilMD PWOXItM 11 sno 140 • iii ins III (MUM eawA .219 M ucpoais IJII sal coasiautTOi •444 121 510 a«Art. SPASI .1 1 4S. Ml i\e w w

21 twiaiiso WIICO .24 111 II 180 lucmtut 110 euiCAaiA 11 AIT SicoaryjH .1 , SC XI ID. 14 n •ucuatn H III MS PtfU 3 SKIS II 411 - ! Vi BKUIS rer si ocu 01HU 12/3114 , MO •i ' 2)4 SWtOM POLAND r DO 2JI • S SUFTU , US 0EHU0 1102 IMS SOUlHVAtSI II ' COAVOUNOS AfRICA USSB ISO. u ixpoaij PAsirs 2AMBI4 TUCOSlAVIA •12 ' •il in II III M JKI TH1HICA1S 40 PI oni s fspueic 2AMt .11 ' sfousm rows 1/1/14 Of OCMA IS 175 uu no, KIT tuuta paooucrs a ISTSUTI ,20 , SWIM IOIIA WISI UftMAirr a i2 sc siaaOAWi nrjusmiii ctASSSCAieoa SC 30 HI. 171 UHll 1HOUSAM) JWMI ions CI 2a£ u°>l • mm

1 tirusiit of -—SAfOftiv euiM Aire coavounas » AUSTMllA •it | lOfUA MO II

JAPAI suracais of 211 - -VJ sraxnj uassu lis

34 I a 01 Hll •S3 II III **

WORLD TOTAL • UtEAU Of MINSS 6,114. US. OCPABIMlNT Of INTIIIOt

-273- Zinc supply-demand relationships, 1965-74 (Thousand short tons, zinc content) 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 World production: United States 611 573 549 529 553 534 503 478 479 500 Rest of world 4,131 4,369 4,781 4,955 5,335 S.489 5,576 5.743 5,818 5,884 Total 4,742 4,942 5,330 5,484 5,888 6,023 6,079 6,221 6,297 6,384 Components of U.S. supply: Domestic mines 611 573 549 529 553 534 503 478 479 500 From old scrap 82 86 80 80 82 72 80 79 89 75 Shipments of Government stockpile excesses 192 101 14 38 18 1 3 188 273 285 Imports, metal 153 278 222 305 325 270 320 523 592 540 Imports, ore 428 521 534 543 602 526 343 255 200 240 Imports, compounds 12 14 13 15 15 13 14 18 26 27 Industry stocks, Jsn. 1 140 179 194 184 167 168 191 133 146 135 Total U.S. supply 1,618 1,752 1,606 1,694 1,762 1,584 1,454 1,674 1,805 1,802 Distribution of U.S. supply: Industry stocks, Dec. 31 179 194 184 167 168 191 133 146 135 234 Exports, metal 6 1 17 33 9 13 4 15 19 Exports, compounds 243335556 10 Industrial demand 1,431 1,553 1,402 1,491 1,582 1.388 1,303 1,519 1,649 1,539 U.S. demand pattern: Metal: Construction 477 518 468 496 526 459 409 489 533 510 Transportation 336 366 330 351 372 325 285 335 367 320 Electrical 168 183 165 175 186 162 135 166 180 170 Machinery 126 137 124 131 139 121 105 126 140 127 Other 154 167 151 161 171 148 139 169 185 180 Total metal 1.261 1,371 1,238 1,314 1,394 1,215 1,073 1,285 1,405 1,307 Horusetal: Paint 36 36 31 30 30 28 35 35 37 35 Chemicals 12 22 30 37 43 39 55 57 60 60 Rubber products 93 98 85 92 98 90 123 125 130 120 Other 29 26 18 18 17 16 17 17 17 17 Total nonmetal 170 182 164 177 188 173 230 234 244 232 Total U.S. demand 1,431 1,553 1,402 1,491 1,582 1,388 1,303 1,519 1,649 1,539 Total U.S. primary demand (industrial demand less old scrap)- l'3*9 L**7 L3" »•*« ».500 1.31» 1.223 1.440 1.560 1.464 TOJ»ltaiSdemln1nie.°roSdis1^-"- 1.179 1.285 1.158 1.234 1.312 1.143 993 1.206 1.316 1.232

- 274 - ZIRCONIUM tactic eaoouciiOH SUTftT­OtMAND t(UTFONSH«?S­lf 74

IOUTN I'KI LEL

itu

­C ipn~

AWSI4A.I4 W0C4J oa> CCKM.C1 U10

mmni cum

WHI nu>'i MIIA1 iwgeil u m '

".I I _ I iMWm S4IAI L .. eui HCHAV. «IH

■ IT 44 Sat | AMrUO WtaHMt tUMMfJI** wan WW) toes at mcaataj wn

avOAicotciaiMfi ■c'oaisoia ■^WISIHIAI ^­­­l­LJV WriW'.CR1IHC*4l lavmmaai siicani amABCt miti taw

WCMHO TOIAI I44.4IO. IUIIAU Of MINI I til MPAJIaUM Of (Mfiaios

Zirconium eupply­dmaand relatlonahlpe, 1965­74 (Short tone clrconlum content) l_/

196) 1966 1967 1968 1969 1970 1971 1972 1973 1974

Vorld production­ United Statea — VWVWWVWW 60,000 W teat ol world — 148.000 158.000 196.000 208.000 239.000 236.000 264.371 245.173 2'4.I75 266.630 Total W JJ V V W W U W 314.175 W Componente of U.S. aupply ', Doncetle mlnea UWWWWWWW 60,000 W Government teleaaca (net)­­­­— — — ­­­ — — ­ — — —­ — Importa. tlrcon 29,000 28,000 30,000 30,000 47,000 47,000 48,666 34,285 49,115 33.5)0 lmsorte, metala 4 alloya ­­­ 1,000 — 671 663 254 367 lmporte, nonmetals­­ ­­—— ­­­ — —­ —­ —­ —­ — —­ 724 770 lnduatry atocka, Jan. I 21 W w W U w V W V 33.768 W Totat U.S. aupply UWWWWWWW 141,881 W Dlatrlbutlon of U.S. aupply lnduatry atocka, Dae. 31 V UWWWWWWW 53,688 H IJcporte. alrcon, nonmetal 1,000 1,000 1,000 1,000 2,000 2,000 4,714 1,162 13,232 22.230 Sxporta, metala 4 alloya— — — — 1,000 1,000 979 657 508 626 Demand­­ UWWWWWWW 74,433 V Apparent aurplua (+), deficit (­) aupply _j3.491 +4,000 4­3.500 4­3.800 ♦2.700 ♦3.200 ♦3.900 U.S. demand pattern: "~ Nonmacal: Iron 4 ateal foundrlea 44,000 43,000 31,000 35.000 48,000 49,000 48,483 46,000 46,)00 40,000 tafraetorlea­ 8,000 11,000 14,000 11,000 13,000 11,000 11,500 12,500 13.300 20.000 Caramlca acd (We 3,000 8,000 13,000 11.000 13,000 9,000 9,000 9,000 11,000 7,300 Chemical ■ " 1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000 Total « 58.000 61,000 59,000 58.000 75,000 70,000 69.983 68,500 72,000 68,500 Metal: Fabricated metal producta 180 200 220 240 260 280 300 323 300 280 •holography HA HA HA 3 10 20 30 30 )) )0 Huclaar reactera W w w w V w w W 2.100 w Total­ ­ W U V W W W W W 2.453 W

Total U.S. primary demand­­ UWWWWWWW 74,433 W Total U.S. demand for primary metal WVWBWlfWW 2,453 V

■A Hot available. W Withheld to avoid hafnium. £/ Kacludca foundrlea (unknown).

­275­ .'.THIS PAGE WAS INTENTIONALLY LEFT' BLANK

, Appendix III. Phase Diagrams of Selected Metal Fluoride Mixtures

/

-277- Figure Ar3 1000 LiF­NaF Figure A­l KF­LiF

1000 1 i i i 990o, 800

900 ­­ Liquid / 600

400 LiF 20 40 60 80 KF 800 ­ Mol % R. E. Thoma, B. J. Sturm, and E. H. Guinn, Oak Ridge National Laboratory, ORNL­3594, p. 30 (Ailg'., 700 ­ LiF NaF 1964). ♦Liquid + Liquid \/teZ° LiF + NaF LiF­CaF2 Figure A­4 600 i i i i 0 20 40 60 80 100 1400 LiF Mol.% NaF

A. G. Bergman and E. P. Dergunov, Compt. rend. acad. set., U.R.S.S., 31, 755 (19­11). 1200

EiF­MgF2 Liq+CoF2 1000 ­

1200

800 1000 CoF, + LiF _J i i i i ' < i „ r 20 40 60 80 lr CoF* Mol % UF 800­ \V. E. Roake, /. Electrochem. Soc, 104, 6CI (1957).

600

LiF­MnF2 Figure A­5 1000 i—i—i—r 400 i—r LiF 20 40 60 MgF, Mol % 900

W. E. Counts, Rustum Roy. and E. F. Osborn. /. Am. Ceram. Soc, 36 [1] 15 (1953). 800

700

600

500 J i i i i UiF 20 40 60 80 MnF Mol.%

I. N. Relyacv and O. Va. koviiia, Zh. Morgan. Khim , 11 |fi] (li)G(i); Huss. J. Inorg,. Chim (Entfi.sh Truml ). 774 (lSHWi). ­278­ Figure A-8 Figure A-6

40 60 Mol%

R. E. Moore, F. F. Blankenship, W. R. Grimes, H. A. Friedman, C. j. Barton, R. E. Tlionia, and H. Insley, Oak Ridge National Laboratory, Phase Diagrams of Nu• UF clear Reactor Materials, R. E. Thoma, ed., ORNL-2548, p. 53(1959). O. Schinitz-Dutnont and Horst Borncfcld, Z. anorg. u allgem. Chem., 287, 121 (1956). LiF-CrF,

Figure A-7 LiF-CeFj Figure A-9

IUV 1 1 I i 1 1 1 y - y \ 1400 y - \ y y \ Liquid - y y 900 y \ 852° y ' — 1200 y _

700 — 1000 jT u. : 500 3 - 800 ^^*\ / 1 1 25 50 75 1 1 .1 _l CrF, LiF Mol % LiF 20 40 60 80 CeFj Mol.%

C. J. Barton. L. M. Bratchcr, R. J. Sheil, and \V. R. Grimes, Oak Ridge National Labor;itory, Phase Diagrams of Nuclear Reactor Materials. R E. Thoma, cd., ORNL- A. IV Kn/.il,. C. K. Aunt. Sn . .SVi C. 268 ["i| 117 (ll«i!»). 2548, p. 09 (1959).

-279- KF­NaF Figure A­10 NaF­CaF2 Figure A­12

950 1300 ­ \ ­

1200 ­ 850 \ Liquid

1100 ­

750

1000 ­ ­ (60%) (­95%)^.

CaF^+Liquid \ 650 900 /NaF+ " J I l I I J I L 20 40 60 80 / Liquid NaF KF Mol % 800 CaF2*NaF i i i i 0 20 40 60 80 100 J. L Holm. Ada Chem Scand. 19 [3] 641 (I961)) CoF2 Mol.% NaF

P. P. Fedotieff and W. P. Iljinskil, Z. anorg. u. allgem. Chem., 129, 101 (1923).

NaF­MgF2 Figure A­ll rioo 1270" t-t,\ a*2 Figure A­13 ~~\ ' ' 1 i

1200 ­

800

1100 600 MgF2 IM ♦ Liquid U. o Z 1 1 tooo 400 i i NoF 20 40 60 80 ZnF, Mol %

NaF­MgF C. J. Barton, L. M. Bratchcr, and W. R. Grimes, Oak 900 2 Ridge National Laboratory, Phase Diagrams of Nuclear ♦ MgF2 Reactor Materials, R E. Thoma. ed , ORNL­2548. p 48 NaF (1959). ♦ Liquid See also O. Schmitz­Dumont and Horst Bornefeld, Z. anorg. u. allgem. Chem , 287, 121 (1956). 800 NaF* MgF; 0 20 40 60 80 100 NaF Mol.'ft MgF2

A. G. Bergman and E. P Dergunov, Compt. rend. acad. sci., U.R.S.S., 31, 755 (1941). ­280 ­ NaF-MnF- Figure A-14 NaF-ZrF4 Figure A-16 ; i i < ill! '■ 1 ■ 1 T — 1 1— 1 1000 998°

923° 1000 900 Liq u rd y/l i // 1 / / 800 1 / / 1 800 - 5NoF-2Zrr; 7f r / \ p^/738°/ 600 a f a i fi 700 692° \/ K t* t i / U. i •J 400 h z i u- 600 i r,6 0° \ \ lO Z z i ■^ I 1 1 i i £l i 40 60 80 NoF -20 ZrF4 Mol % 500 u. ■~ rvj 2 u. C J. Barton, W. R. Grimes, H. Insley, R. E. Moore, and u. R. E. Thoma, /. Phys. Chem., 62, 006 (193S). 200 o 2 Z 140° NaF-FeFj inn 1 ! 1 1 I'll Figure A-17 NoF 20 40 60 80 MnF, 1100 i i i i Mol.%

I. N. Belyaev and O. Va Rcvina, Zh Ncorv.au Khim , 11 [6| 1446 (1906), Rim. J. Innrg Chem. (English Transl ), 774 1000 - (1966).

\ y Figure A-15 900 \y -

i i i i 0 10 20 30 40 50 NoF Mol. V. Pery*-

N. Puschin and A. Baskow, Z. anorg. Chem , 81, 361(1913)

NaF-FeF2 Figure A-18

l£UU 1 r -i— :— i ■■■! -i i i

1000 / -

800 X ^-1r-^s

600 £ ■

,..,2 20 40 60 80 NoF FeF2 pbFl 20 40 60 NoF Mol% Mol. %

O. Schiiiit7-I)uiinml and Gunlcr BcrgcrholT. Z. /Innrg Allgem R. E. Thoina, H. A. Friedman, B. S. Landau, and C/!cw;.,283,:Jl7(l''.".'i). W. R. Grimes,.Oak Ridge National Laboratory Phase Diagrams of Nuclear Reactor Materials, R. Ii. Thoma, ed., ORNL 2548. p. 26 (1959). -281- NaF­BF 3 Figure A­21

woo LIQUIDUS S0LIDUS 900 ° CRYSTAL INVERSION

800 ­ LIQUID­ NoF ♦ LIQUID ' 700 N [ 600 No8F4 (HIGH­TEMPERATURE FORM) \ 500 + LIQUID —

400 384'C ­

_NoF + NoBF (HIGH­TEMPERATURE FORM). 300 4

NoF ♦ NoBF. (LOW­TEMPERATURE FORM) 40 60 200 NoF NoF 20 40 60 80 NoBF. Mol % No8F4 (mol«%>

C. J. Barton, L. 0. Gilpatrick, A. Dc Kci/.ik. C. R Acad Sci . Ser. C. 268 [.".] 117 (I «)<)«>). J. A. Bornmann, H. H. Stone, T. N. McVay, and H. Insley, J. Inorg. Nucl. Chem. 33:337 (1971)

NaF­CeFe*3j Figure A­22 NaF­NiF i i 2 Figure A­20 I46Q°> 1 1 1 r­ I r 1 1 ­^ 1 1400

1200 yy jy - 1200 ­ ­ r-^S 1000 -

N. / 1000 ^996" ­ ' 800 if Z 800 u. 726* * NaF­CeFj 600 i i i i ■ i ...i20 t NoF 40 60 60 NiF, „ c 20 40 60 80 r _ Mol% NoF Mol% CeF»

R. E. Thoma, H. A. Friedman, B. S. Landau, and C. J. Barton, J. D. Redman, and R. A. Strehlow, AV. R. Grimes, Oak Ridge National Laboratory J. Inorg. Nucl. Chem., 20, 45­54 (1961). Phase Diagrams for Nuclear Reactor Materials, R. E. Thoma, ed., ORNL­2548, p. 27 (1959).

­282­ NoBF4-KBF4 Figure A-23

TOO

600

500

400

30O

200

400 10 20 30 40 SO 60 90 NaBF« NoBF4(mo'e*7>)

R. E. Moore, J. G. Surak, and W. R. Grimes, unpublished work per• formed at the Oak Ridge National Laboratory, 1957.

NaF-SnF2 Figure A-24

450

400

350

300

250

200 £ c* i" 11/"" 150 2 2 z

2 ICO NaF 20 40 60 80 SnF, SnF2(mole %)

J. D. Donaldson et al., J. Chem. Soc. 1965 (714):3876. - 283 - Figure A­25

KF­CaF2 WOO 1360° y

KF­BF­ Figure A­26 1200 L quid

857'C LIQUID i2£2*L/ 1060° KBF, (HIGH­TEMPERATURE FORM) 1000 700 KF + LIQUID V ♦ Ll0UI0,v ^ 570"C t­ 600 860° 1 \ 3 1 a 500 460'C 800 . 1 ^^Z. |*oo 782° i "KF+KBF4 (HIGH­TEMPERATURE FORM) 1 I ^300 — ZBVC

KF ♦ KBF4 200 ■ • LIOUIOUS ■ (LOW­TEMPERATURE FORM) 600 ■ • SOLIOUS Is o CRYSTAL INVERSION 100

0 (O 20 30 10 50 60 70 80 90 100 20 . 40. 1 6.0 KF 80 CaF2 KF KBF4 (molt TO KBF4 Mol %

oluni M.id Isli.iquc \ Hull Sm Chim Frame. 1952 C. J. Barton et al., J. Inorg. 11­2] p l.«) Nucl. Chem. 33, 337 (1971).

KF­BF

KF­MgF2 Figur B k^­2 7

1300 1 1 r 1270° | a *Liq^CT ~a. */3 s s\. I Liquid y^ a ♦ Liq >^ |

­ 1100 * 101'0 ° / MgF2 ♦ Liquid

V / / y ^v/ loos* / / 1 ^­KMgFj ss + Liquid Liquid / KMgF, ss / / * 1 900 / Liquid / /846° /xMqF, s ss KFTUQ\/><2M9F4 * L'<* N \ KMgF, ss 778° \ MgF, K,MgF 4 ­ 700 KMgF, ss KF ♦ K2MgF4

Z 2 u. u. CM 500 1 60 60 K F 2C 40 Mi Mo %

R. C. DeVries and Rustum Roy, /. Am. Chem. Soc, 75, 2481 (1953).

-2Qk- Figure A-29 KF-ZnF2 1000 1 1 i i 1 1 1 - I 1

800 \■ N^ ^^N. / - Figure A-28 600 . -

M Lu * 400 CJ

! 1 1 1 80 KF 20 40 60 ZnF2 Mol°/0

C. J. Barton, L M. Bratchcr, and \V. R Grimes, Oak Ridge National Laboratory, Phase Diagrams of Nuclear Reactor Materials, R. Ii. Thoma, ed.. ORNL-2548, p. -iQ (1959) See also O. Sclimitz-Diimont and Horst Bornefeld, Z. anorg u. ullgcm OKHI., 287, 122 (195U).

Figure A-30 ll0 KF-MnF2 ° 1 ! 1 1 1 1. i 1 1 1032° Liq ui d 1000 -

V 923° 900 h- \ / 852° \ / 814° \/ / 795° 800 h 0 20 40 60 60 100 / 787° KF 743° \ Mol. % ZrF, u_ 1 be: 700 I . 1 I . 1 i A. V. Xovosclova, Yu. M. Kiircnov, and Vu. P Siinanov, 20 40 60 80 MnF, Doklmlv Akad. Sank S S S. R . 139 I I! S!>;j (l!l(il). See KF also C. J. H.irton, II Iii-.lt->-. Ii. Ii MiU-.ilf, li li. Thom.i, ' Mol and W. Ii. Griino, Oak Ridge National Laboratory, Phase Diagrams of Nuclear Reactor Materials, K. 15. I. N. Belyaev and 0. Ya. Revina, Zh. Thoma, ed., 01iNrL-2."> IS (I!l."i9). Neorgan. Khim., U_ [6] 1446 (1966); Russ. J. Inorg. Chem. (English Transl.), 774 (1966).

- 285 - KF­SnF„ Figure A­33

Figure A­31 450 KF­NiF2 I

400

350

300 —\

a 250 2

200 / if' "■f ■fe £ /

150

100 .j<*­ Wagner and D Balz. Z. Elektrochem. 56, 570 KF 20 40 60 80 SnF, SnF2(mole %)

J. D. Donaldson et al. J. Chem. Soc. 1965 (714):3876.

KF CeF, Figure A­32 Figure A­34

858

800

700 ­

600

p p 20 40 60 b 2 80 KF Mol. % G. A. Bukhalova and E. P. Babaeva, 0. Schmitz­Dumont and Gunter Bergerhoff, Zh. Neorgan. Khim., 11 [3] 624 Z. Anorg. Allgem. Chem., 283, 317 (1956), (1966); Russ. J. Inorg. Chem. (English Transl.), 339 (1966).

­286­ Figure A-35 KF-CoF, Figure A-36 KF-BaF 2'

1100 1200 I I 1 1 42° ' 1032° ™ 1050 - -

1100 1009° 1000 945° 950

WOO ^865° / _ 900 o 858 ° / 848° w 850 -^ - u 900

< 800 (E \ V 750° 800 5 750 xC 729* 700 - - u 700 650

600 - 580° 600

550 -

I 1 500 500 KF 20 40 60 80 BoF, KF 25 50 75 CoF, BaFj (mole %)

G. A. Bukhalova and E. S. I. N. Belyaev and S. A. Shilov, Vagub'yan, Izv. Akad. Nauk. Russ. J. Inorg. Chem., 14, 1046 SSSR, Neorg. Mater. , _3_, 1096 (1969). (1967); V. T. Berezhnaya and G. A. Bukhalova, Russ. J. Inorg. Chem., 12,JL143 (1967)

CaF2-MgF2 Figure A-37

l 1 1 1 1 1 1 1 1410* 1400

1300 Liquid / - 1252°

1200 - X -

1100 - -

- 1000 980°C \/(5 5 6%) I 1 1 I 1 1 1 1 ., c 20 40 60 80 -_ MgFj CoF2 Wt %

M. Rolin and M Cl.nibier, Rev. Int. Haute\ Temp Refract., 4 [1] -12(1967).

- 287- MgF2-CaF2. Figure A-38 1300

y 1400 y y /' y y y 1300 y y ^-^ y y •*>. S 1200 > V y y y -v J 1100 x. r«i/ V. o y u «""

900 MgF- «0 20 30 40 30 60 70 80 90 CoF, CoF, (moH«.l

C. J. Barton, L. M. Bratcher and J. P. Blakely, ORNL, unpublished work.

BaF2-MgF. BaF -CaF 2 2 Figure A-40

1 1 1 1 1 1 r i i 1410° 1400

Liquid I3385 1300 fi II

1200 1 -

f BaFj ss 1100 1070° jP50°_ r 1 l~ "i r **k i i 20 40 60 80 CoF, BoF, Wt %

M. Rolin and M. Clausier, Rev. Int. M. Rolin and M. Clausier, Rev. Int. Hautes Temp. Refract., 4 [1] 42 Hautes Temp. Refract., 4 [1] 42 (1967). *~ (1967). ~*

-288. 1

FeF2-PbF2 pigure A_41

1 1 1 1

900- BaF2-ZnF2 Figure A-43

Liquid 1 1 1 800 - 1320° 1300

700-- 1200 - / - \ 628° / 623° _620° - (60%1 (72%) 600- 1100 -

Liquid / li- 500-- 1000 0. Li- 947° /

400 1 1 1 900 20 '40 60 80 FeF, PbF, \ (36%) / Mol % \ 7f2°(45%) /(59 5%) \ \ 775° „„.. \^S 795° _ 800 rou- 'V \ V LS \/762° M. Samouel, Rev. Chim. Miner., 8 [4] (25%)- S\^~\ (53 5%) 545 (1971). *~ 740° (32 5%) 700 — — rbi" 2-£nr2 Figure A-42 o i i i 1 uT » Lif 947° 600 u. <= - M N c rvi M tsi

603° \ ££!/ « 600 cnn (54%) (71.5%)

500 - • * u. • c M 400 J3 0. 1 1 1 " ZnF, 20 40 60 80 Moi % PbF, M. Samouel, Rev. Chim. Miner., 8 [4] 542 (1971). -289- MnF2­PbF2 BaF ­CuF Figure A­44 2 2 Figure A­46 1 1 l 1 1320° 1300 — /*—

1200 ­ / ­

1100 ~ Liquid / ­

1000 ­

900| (65%)/ ' 663° _ 856°

800 _ N. (50 5%1f 76A' \ (34 5%)y^ 700 (26°^ >. V/663° V &.624° |\./6I6° 600 a 605~~ (27 5%) $ 532° 500 _ a a 10 uT V0 » u. 400 3 U. 3 3 CJ u 3 (J M O 300 O ° ,S 40 60 — CO CO CD 1 m 1 1 Mol % 20 40 60 80 CuF 1 BoF2 2 Mol % M. Samouel, Rev. Chim. Miner., 8^J4] 546 (1971). M S..IH..IK­I, r R Acad Sti.Sei C. 270 [■_''.»] 1805 (1«)70)

LiF­AlF3 Figure A­45 NaF­AlF, 900 Figure A­47

1000

800 900

800

700 700

650 LiF 10 20 30 40 50 AIF, NoF Mol % C. N. Cochran, Trans. AIME, 239 [7] 1058 (1967). E. P. Dergunov, Dokl. Akad. Nauk SSSR, 60 [7] 1185 (1948).

­290­ NaF' -CaF -AlF Figure A-48 KF-AIFj 2 3 Figure A-50 wt % 0 5 10 20 40 1000 T T 1420° 1400

1300-

1200

K3AIF6 1100 eub,cWl'CublcKAIF«+AIF* £ CoFj + Liq

1000 ~ -15° / K3AIF6*Qrtho KAIF«

945 5° T Ortho KAIF4 f AIF3 \ (50%) 100 _i_ _i_ 900 _ /9NosAIF6 + Liq KF 20 \ 40 \ 60 80 A,p KF Alh 3KFAIF3 KFAIF3 3 0No,AIF6 + CoF2 Mol. %

J I. I J L Bert Phillips, C. M. Warshav;, and I. ,. ..r 20 40 60 80 Mockrin, J. Am. Ceram. Soc, 49 [12] No3AIF6 CaF, Mol % 2 633 (1966). ~* J. L. Holm, Acta Chem. Scand., 22 [3] 1006 (1968).

CaF2-AlF3 Figure A-49 Li3AlF6-K3AlF6 Figure A-51

U20

,— PAIFJ = 1 atrn 1200 liq. J .n-CaAlFsMiq / 1000 AlFj'liq CaFj-liq K 881 °C 828'C \£F .800 CaFj»IVCaAlFVT li-CaAIF5. AlFj AAA y a ft

600 CaFj «o-CaAlF5 a-CaAlF5>A|F3

too

0 20 (0 60 80 100 C.lFj Mol« % AlF, —. AIF, "0 20 tu eo eo 100 l.,*IF, Mol°'< K,4ir. KiAlFj J. L. Holm, Acta Chem. Scand., 19 (6), 1512 (1965). K. Grjotheim, et al., Acta Chem. Scand., 25, 1695 (1971)

-29I- Figure A­54 LiF­NaF­AlFj AIF

PbF2­AIF3 Figure A­52

900

700

AIFj+ PbjAI2F,j 500 PbjAljF,^ PbF, ss •• PbF2ss

3PbF,­2AIFj­ I _l_l_ 40 60 80 AIF, Mol % PbF,

NoF 652° LiF Mol % m a, IBM W mM,S,,f "" " '"«"W* .Ce ram Soc ,52 [2] R E Thoma B I Sturm and Ii 11 ('.mini. Oak Uiduc Natl Lab,ORNL­3594,p 3J (Aug 19(14)

NaF­MgF2­AlF3 Figure A­55 NaF­MgF2­AlFi Figure A­53 AlFj

1 1 1 1 1050­­ •

Liquid ■ 1000 ^^y

950 ­ \ -

1 , 900 ­ -

850 1 , . \ . 3NoFAIF35 10 15 20 25 30 35MgFj_

No3AIF6 A. M Romanovskii and Va K Remit. f.a>kic Metal , No. 6, 34 (19Jo) E. Vatslavik and A I Belyaev, Zhur. Neorg. Khim , 3, 1045(1958)

­292­ KF-NaF-AlF3 Figure A-57

No/, NaF-CaF2-AlF3 Figure A-56

A1F3

K.AIF, Mol % oes'i

P. P. FedotiefT and W. P. Iljinskil, Z. anorg. u. allgem. Chem., 120, pp. 10G, 107 (1923). O A Bukhalova and V T Mai tv-cv Zh Xcmi;aii Khim 10 [1| 189 n%.">) «»vv J hmrg Chem (Englnh Trailu ) 101 (1%.-))

AIF, Figure A-58 (~I400°)

KF-AlF3-ZrF4

KAIF, (575°l

ZrF« (910°)

R. Ii Thoma B J Strum, and li II Gumii, Oak Ridge Natl Lab , ORNL-3594, p 33(AUL; 19(14)

-293- LiF-KF-AlF3 Figure A-59 KF-LiF-NaF Figure A-61 NaF (990°

WWWWUi<

tM ••»" tor nr nr too- /\~~~'-

R. E. Thoma, B. J. Sturm, and E. H. Guinn, A. G. Bergman and E. P. Dergunov, Compt. rend, acad Molten-Salt Solvents for Fluoride Vola• sci.. U R.S.S., 31, 754 (1941). tility Processing of Aluminum Matrix Nuclear Fuel Elements, ORNL-3594, 1964.

LiF-NaF-CaF2 Figure A-62 LiF-NaF-MgF2 Figure A-60

NaF 830° NaFMgF2 1000° MqF2 (990°) (1030°) (1270°) Mol.% C. J. Barton. L. M. Bratcher, and W. R. Crimes. Oak Ridge National Laboratory, Phase Diagrams of Nudear A. G. Bergman and E. P. Dergunov, Compt. rend. acad. Reactor Materials, R E Thoma, ed , ORNL-2548. p 29 sci., U.R.S.S., 31, 755 (1941). (1959) See also G A. Bukhalova, K Sulalmankulov, and A K Bostandzhijan. Zhur Neorg Khun , 4, 1138 (1959)

-2911-- LiF-NaF-ZrF4 Figure A-63

3LiF 4ZrF. F. F. Blankcnship, H A Friedman, R E. Thoma, and \V R. Grimes. O.ik P-520° Ridge Nalioii.il Laboratory, Phase E-507° Diagrams of Nuclear Reactor Mate• rials, U. E. Thoma, cd , ORNL-2548 p. 61 (1959).

2LiF ZrF4 E-570° ZLiF ZrF, E-605°

E-652° 845° Mol %

LiF NaF-BaF, Figure A-64

850°

LiF.BoF2

V. T. Berezhnaya and G. A. Bukhalova, Zh. Neorgan. Khim., 4. [11] 2600 (1959); Russ. J. Inorg. Chem. (Eng• lish Transl.), 1200 (1959).

Na2F2 BoF2 (990°) (1280°)

-295- LiF -NaF-SrF2 Figure A-65 KF-LiF-MgF2 Figure A-67

L,2F2 (84 8°)

742°(min)

mi K(r 786° 070° 2KFMgF2KFMgF2 MgF2 (850°) (1054°) 11270°) Mol%

(990°) A. G. Bergman and S. P. Parlenko, Compt. rend. acad. sci.. U.R.S.S.. 31, 818-19 (1941) V. T. Berezhnaya and G. A. Bukhalova, Zh Neorgan. Khim., 5 [4] 925 (1960); Russ. J. Inorg. Chem. (English Transl.), 445 (1960),

KF-LiF-BaF2 Figure A-68 KF LiF SrF, Figure A-66

(848°)

Sr F * K2F2 729° BoF2 (858°) Mol % (1400°) (e52°) (1280°) Mol.%

V. T. Berezhnaya and G. A. Bukhalova, Zh. V. T. Berezhnaya and G. A. Bukhalova, Zh Neorgan. Khim.. 5 [4] 925 (1960); Russ. J. Neorgan. Khim., .4 [11] 2600 (1959); Russ. Inorg. Chem. (English Transl.). 446 (1960) J. Inorg. Chem. '^(English Transl.), 1199 (1959).

-296- LiF-MgF2-SrF2 Figure A-69

LiF-CaF2-MgF2 Figure A-71 (848°)

74 2 (Mia)

MgF SrF,

Z. A. Mateiko and G. A. Bukhalova, Zh. W. E. Roake, J. Electrochem. Soc, 104^, Neorgan. Khim.. 7 fl] 165 (1962); Russ. 662 (1957). See also V. T. Berezhnaya J. Inorg. Chem. (English Transl.), 84 and G. A. Bukhalova, Zhur. Neorg. Khim., (1962). 4, 903 (1959).

LiF-BaF2-SrF2 Figure A-72 LiF-BaF2-MgF2 Figure A-70

(848°)

BoF2 BaF2 SrF2 1280° (1280°) Mol % (1400°)

G, A, Bukhalova and V. T, Berezhnaya, Z, A, Mateiko and G. A. Bukhalova, Zh. Zhur. Neorg. Khim., 4^[5] 1141 (1959). Neorgan, Khim., 7_ [1] 165 (1962); Russ. J. Inorg. Chem. (English Transl.), 85 (1962).

-297- LiF-BaF2-CaF2 Figure A-73 LiF-CaF2-SrF2 Figure A-75

L,2F, <8«8*>

Solid Solution

_* X Vi y v/ v/ v v v CoF2 20 40 60 80 SrF 2 "-1"01 Mol % (1400°) CoF. BoF2 1411° 1280° Z. A Mateiko and G. A. Bukhalova, Zh Neorgan Khim., 6 |7| 1727 flOOl), /CHM. 7. /wo/-s C/ww/. (English Transl), 882(1901). G. A. Bukhalova and V. T. Berezhnaya, Zhur. Neorg. Khim 2 [6] 1409 (1957).

KF-NaF-MgF2 Figure A-74 NaF-CaF2-MgF2 Figure A-76 NoF (990°) CoF2 1418°

NoFMgF2 (1030°) 685° -710°

NoF 830° NoF-MgF2 (1030°) MgFj, 990' Mol % 1270"

C. J. Barton. L. M. Bratcher, J. P. Blakely, and \V. R. Mar M250" lnino/ KF-MaF X ?KFMnF -o™<,^ ,oc.' KF Grimes, Oak Ridge National Laboratory, Phase Diagrams <.?7O01 IIO60S* 2KFM9F2 870°. 786" KF of Nuclear Reactor Materials. R. E. Thoma. ed.. OR, *1270 > (1060) (8508) 2548, p. 30(1959). Mol %

A. G. Bergman and E. P. Dergunov, Compt. rend. acad. set., U.R.S.S., 48 330 (1945). -298- NaF CaF SrF KF-NaF-ZrF, Figure A-77 2 2 Figure A-79 IMOJFJ (993°)

2NoF 3KF 5ZrF4 3NoF 4ZrF4 E 440° P537° E5I2° KF ZrF4 7NoF 6ZrF4 E 390° E 500 P4I2° P 544°/ 3KF 2ZrF4 P 640° ' P590° 2KF ZrF 2NoFZr 4 5NaF 2ZrF4 ZrF4 3IMoFZrF4^L NoFKF ZrF E 747° **S= 4 G. A. Bukhalova, V T. Hcrczhiiaya, and Z. A. Mateik i E765* Zh. Neorgan. Khim., 7 |9| 22.i:i (1902); Kins. J. fnoig. Chi h (English Transl.), 1 lot! 119112).

R. E. Thoma, C. J. Barton. H. Insley, H. A. Friedman and W R. G"ines, Oak Ridge National Laboratory, Phase Diagrams of Nuclear Reactor Ma• terials, R, E. Thoma, ed . OU NL-2518. i> 03 (1959).

NaF-BaF2-CaF2 Figure A-78 (990°) NaF-BaF2 -SrF2 Figure A-80

(993°)

CoF2 Min. 1022° BoF2 SrF;, n°) Mol. X (12 8 0°) Mol. % (1400°)

G A Biikhalov.i, Z A. Mateiko. and V. T. Bcrtv.liuay.-i. G. A. Bukhalova. V. T Berezhnaya. and A G. Bergman. Zh. Neorgan. Zh. Neorgan. Khun . 7 |7| lO.Vi (1902); Knss J. Innrg Khim.. 6 |10| 2:j.->9 (1901), Russ. J. Innrg Chem'. (English Transl.), Chem. (English Transl.), N50 (1902). 1197(1901). -299- KF-BaF2-SrF2 BaF2-CaF2-MgF2 Figure A-81 Figure A-83

K2F2 (856°) MgF2 (1396°)

BoF2-2MgF2

BoF2 SrF2 (1280°) Mol. % (1400°)

G. A. Bukhalova, Z. A. Mateiko, and V. T. Berezhnaya, Zh. Neorgan. Khim., T.IT\ 1655 (1962); Russ. J. Inorg. CoF z Min. 1022° BoF2 Chem. (English Transl.), 856 (1962). (1411°) Mol. % (1280°) V. T. Berezhnaya and G. A. Bukhalova, Zh. Neorgan. Khim., 6 [9] 2136 (1961); Russ. J. Inorg. Chem. (English Transl.), 1091 (1961),

KF-BaF2-CaF2 Figure A-82 KF-CaF2-SrF2 Figure A-84 (856°) K2F2 (856°)

KCaFs (1070°), 1058

KCoFj (1070 1058"

G. A. Bukhalova, V, T. Berezhnaya, and Z. A. Mateiko, Zh. Neorgan. Khim. X [9] 2233 (1962); Russ. J. Inorg. Chem. (English Transl.), 1157 (1 . G. A. Bukhalova, V. T. Berezhnaya, and A. G. Bergman, Zh. Neorgan. Khim., JS^flO] 2359 (1961); Russ. J. Inorg. Chem. (English Transl.), 1197 (1961). -300- Ca-CaF, Figure A-85'

"■"1 1 1 1 1 1 1 1 1 LiF-LiOH Figure A-87

1400 1 1 i i Liquid \ - 800 1300 - -

1200 CoF2 ss + Liquid \ -

600 I \

1100 \ 1 " ■ 1 1 1000 I i 400 (

900 i i i i 0 20 40 60 80 100 LiF Mol % LiOH 800 CoF2 + Co 1 1 i i 1 1 1 I Giuseppe Scarpa, Atti reale 20 40 60 80 CoF, Co accad. Lincei, Sez. II, 24, Mol % 478 (1915).

B. D. Lichter and M. A. Bredig, J. Electrochem. Soc. 112 [5] 508 (1965)

NaF-NaOH Figure A-86 KF-KOH Figure A-88

800

800 - \ -

600 -

600 -

400 - (.

400 \ -

i V—■— 200 -

200 - 0 20 40 60 80 100 i i i ' 0 20 40 60 80 100 KF Mol. % KOH NoF Mol % NaOH Giuseppe Scarpa, Atti reale Giuseppe Scarpa, Atti reale accad. Lincei, Sez. I, 24, accad. Lincei, Sez. I, 24, 744 (1915). 957 (1915). 301- LiF-Li2C03 Figure A-89 900

800

CaF2-CaC03 Figure A-92 700 - 1 1

1400 600

20 40 80 L.2C03 60 LiF Mol.% 0. Schmitz-Dumont and Trmgard 1200 Heckmann, Z. Anorg. Allgem. Chem., 260, 63 (1949).

KCl-NaF-K2C03 Figure A-90 1000 No2F2 (990°) Liquid

800 CQF2 20 40 60 80 coC03 J. Gittins and 0. F. Tuttle, Am. J. Sci., 262, 68 (1964).

KCl-NaF-Na2C03 Figure A-93

(K2CI2) (775°)

KJCOJ (895°)

N. N. Volkov and A. G. Bergman, Compt. Rend. Acad. Sci. URSS, 27 [9] 970 (1940)

NaF-Na2C03 Figure A-91 1000

No2F2 690° No2C03 800 - (990°) (860°) Mol. % N. N. Volkov and A. G. Bergman, Compt. Rend. Acad. Sci. URSS, 27 [9] 970 (1940). 600

80 100 NoF

M. Amadori, Atti reale accad. Lincei, Sez. II. 22, 368 (1913). -302- NaCl­NaF­Na2C03 Figure A­97 KF­K2C03 Figure A­94 No2F2 v i r —i 1 (990°)

800

700 X^ /

600

1 1 1 1 20 40 60 80 100 K2C03 Mol. °/o KF

M. Amadori, Atti reale accad. Lincei, Sez. II, 22, 369 (1913). No2CI2 638° Na2C03 (800°) (860°) Mol. % CaF2­Ca(0H)2 Figure A­95 N. N. Volkov and A. G. Bergman, 1 i 1 Compt. Rend. Acad. Sci. URSS, 27 \ [9] 968 (1940). \ \ LiCl­LiF Figure A­98 1200 \ ­ \ \ \ Liquid — Experimental \ 800 — Clausius­Clapeyron Limit //. 1000 \ ­

Co(OH)2 700

Liquid 800 N 600 CoF2 *■ Liquid \ ­ /

s \ y 500 CoF2 + Cc (0H)2 600 20 40 60 80 CoF2 20 40 60 80 Co(OH)2 LiCI LiF Mol% J. Gittins and 0. F. Tuttle, H. M. Haendler, P. S. Sennett, and Am. J. Sci., 262, 68 (1964). C. M. Wheeler, Jr., J. Electrochem Soc, 106, 265 (1959). KCl­LiF Figure A­96 NaCl­LiF Figure A­99 1000" — Experimental M Experimental — Flood equation — Flood equation — Clausius­Clapeyron Limit ­ Clausius­Clapeyron I

20 40 60 80 KCI 20 40 60 80 Mol% UF LiF NaCl Mol.% H. M. Haendler, P. S. Sennett, H. M. Haendler, P. S. Sennett, and C. M. Wheeler, Jr., J. Elec­ and C. M. Wheeler, Jr., J. Elec­ trochem. Soc, 106, 266 (1959). trochem. Soc, 106, 265 (1959).

­303 ­ Figure A-102 NaCl-NaF 1000 CaCl -CaF 2 2 Figure A-100

900 1 1 1 1 1

850- 900

Liquid 800 — — / CoF2 + Liq 775°

750--\ / 735° ~~ 145%) 800 700 CoF 2 + _ CoCIF 650- 645° u_ _ (18 5%i o

600 1 1 1 1 20 CoCI 40 (I I) 60 CoF,— 700- 2 Mol %

D. A. Wenz, I. Johnson, and R. D. 20 40 60 80 Wolson, J. Chem. Eng. Data, 14 [2] NoCI NoF 252 (1969). Mol % K. Grjotheim, T. Halvorsen, and J. L. Holm, Acta Chem. Scand., 21 [8] 2300 (1967).

MgCl2-MgF2 Figure A-103 Figure A-101 NaCl-AlF3 900 , , , r-=-| , r 1300 1 1 1 1 1 1 1 1 1 y' y 1200 y ~ y y 800 1100 y y y y 1000

700 900 — Liquid -

800 y MgF2 + Liq - 715 1 2° / 600 700 - 20 40 NaCl AIF. 628 12° 600 _ \ (22 0 10 5%) _ + MgF M. A. Kuvakin and P. S. Kusakin, ^MgCI2 + Liq MqCI2 2 500 1 1 1 1 I 1 1 1 i Zh. Neorgan. Khim., 4M[11] 2577 20 40 60 80 MgCI2 MgF2 (1959); Russ. J. Inorg. Chem. Mol% (English Transl.), 1188 (1959). R. A. Sharma and I. Johnson, J. Amer. Ceram. Soc, 52 [11] 613 (1969).

3C4- NaCl­ZrF, Figure A­106 :aCI ­M F 2 g 2 Figure A­104

1000

800

600­

4 00

200­

MgF2

NoCI 20 40 60 80 ZrFd Mol % R. A. Sharma and I. Johnson, J. Amer. Ceram. Soc, 52 [11] 614 (1969). R. Winand, Compt. Rend. Congr. Inter­ natl. Chimie Ind., 31e, Liege, p. 744 (1958).

NaCl­NaF­AlF3 Figure A­105 Figure A­107

NoCI 1300 1 1 1 If 1 1 ■ 1 1 y 1200 y _ y y 1100 y Liquid y

1000

900 ­ / MgF2 + Liq

800 *U 786 ♦ 3° \|4 5 ! 0 5 %) 700 _>­NaCI + Liq NaCl + MgF2 600 1 1 1 1 1 1 i i i 20 40 60 80 NoCI MgF2 Mol %

20 \{ 1/60 80 R. A. Sharma and I. Johnson, J. Amer. NoF AIF3 NajAIFg 5NaF'3AIF3 Ceram. Soc, 52 [11] 615 (1969). M. A. Kuvakin and P. S. Kusakin, Zh. Neorgan. Khim.,_4 [11] 2577 (1959); Russ. J. Inorg. Chem. (English Transl.), 1190 (1959).

­305­ NaCl-LiF- CaF Figure A-108 2 Figure A-110 BaCl2-NaF-CaF2 Na2CI2 (800°)

BoF,- BoCI

Li2F2 766° CoF2 (848°) (1410°) Mol.% N. A. Shul'ga and G. A. Bukhalova, Zhur. Neorg. Khim., 2,2137(1957). V. A. Gladuslicliciiko and M. A. Zakliarclieiiko, Zh. Neorgan. Khim., U [4] 916(1900); Russ J. Inorg Chem (English Transl ), 494 (1906).

Figure A-109 KCl-NaF-BaF2 KCl-KF-BFj Figure A-lll

BoF2 800 r —r- —i— t -i 1 i l !___ (1280°) ^ 600 - *- -

400 ■ •

200 ■ -

0 1 1 1 .1 u i i i i 20 40 60 80 KBF4 KCl

G. V. Samsoiiov, V. A Obolonchik, and G. N. Kulichkina, Khim. Nauka i I'romy., 4, 804 (1959).

No2F2 (990°) Mol. %

G. A. Bukhalova and E. S. Yagub'yan, Zh. Neorgan. Khim , 5 [11| 2503 (19G0); Russ. J. Inorg. Chem (English Transl.), 1213 (1900).

-306- CaF2­MgO Figure A­112

1600 1 Figure A­115 1 I1 CaO­CaF2 I \ 1 1 1 1 2570° \ 2400 ­\ 13901 ­ 1400 ­ \ \ 1350° \ 1 1 2200 ­ \ ­ 25 50 75 \ MgO CoF, \ Mol % \ Liquid 2000 ­ \ P. P. Budmkov and S. G. Tresvyatskil, Ukrain. Khim. \ Zhur., 10, 555 (1953). \ \ 1800 ­ \ ­

Figure A­113 CoO +Liquid \ MgF2­MgO 1350 ~i i i I i I T" 1600 ­

\. /3 CoF2 + Liquid CoO + /?CoF ^ N^ VJ4I9°. Liquid 1400 ­ 2 1300 1 l 1 1 CoO 20 40 60 80 CoF, MgO + Liq, 1250 Joydeb Mukerji, J. Am. Ceram. Soc., 1240°­ 48 [4] 212 (1965). 1214° H 1200

MgO + MgF2 Figure A­116 1150 J L J I I I L MgO 20 40 60 80 MgFz B20j Mol. % LiF­BaF2­B203 (450°) Wilhelm Hinz and P. 0. Kunth, Am. Mineralogist, 45, 1204 (1960).

BoF2'482Oj Figure A­114 NaF­Al203 865' (840°) MOO 1 1 1 t 2BoF2'3B203­/ (895' . 1080 860

Liquid + NoAl02 1060 ­ J

1040 ­ Liquid ­ + 13 Al203 1020 + ­ Liquid ♦ NoF / NoAI02 NoAI0 / 1000 h­ 2 ­

BoF2 LiF'BoF2 856' 980 (1280°) Liquid ♦ NoF + fi Mol.% 960 I l 1 1 S. I. Berul' and I. N. Nikonova, Zh. NoF 8 10 12 Neorgan. Khim., U. [4] 910 (1966); Russ. J. Inorg. Chem. (English Transl.), P. A. Foster, Jr., J. Am. 492 (1966). ' I Ceram. Soc, 45 [4] 146 (1962). ­307­ NaF-CaF2-AlF3-Al203 Figure A-117

Al?03 AW, ,(2050°)

CaF2 3NaFAIF3 CaF, 905° 3NaFAIF3 (1361°) (977°) Liquidus Isotherms Solidus Isotherms

Von P. Pascal, Z. Electrochem., 19, pp. 612, 013 (1913).

lNraF-MgF -AlF -Al 0 Figure A-118 2 3 2 3 NaF-SrF2-KF Figure A-119 20/

(858°)

NOjAIF,

E. Vatslavik and A. I. Belyaev, Zhur. Neorg. Khim., 3, 1044(1958).

SrFj (990°) (1400°) V. T. Berezhnaya and G. A. Bukhalov" Russ. J. Inorg. Chem., 5, 925 (1960

-308- NaF­KF­CaF„ Figure A­120

CsP, (1411°)

1058*

KF CoF2 (1070°)

No2F2 (990°)

G. A. Bukhalova and V. T. Berezhnaya, KF­LiF­NaF­CaF2 Figure A­121 Russ. J. Inorg. Chem., 4, 1197 (1959), v A»H

Na2F2 Figure,A­122

(848°)

Mol %

G A Bukhalova and V 1 Bv.re?lmaya Zh Neorgan Khun , 5 [21 45G (1900), Russ J Inorg Chun (English Transl) 222 (19G0)

CaF2 K2F2 (1411°) (852°)

G A Bukhalova and \ T Biniliuaya Zh Neorgan Khim 5 \2\ !">(■ (1900), Ru

SrF2 (1400°)

V T Berezhnaya and G A Bukhalo\a Zh Nenigan Khim , 5 [9] 2001 (19(50), Russ J Inoig Chem (English Tiantt ), 1002 (1900)

Figure A-124

V. T. Berezhnaya and G A Bukhalova, Zh Neorgan Khim , 5 |9]2001(19G0), Russ J Inorg. Chem (English Transl ), 1005 (1900).

-310- AU.S. GOVERNMENT PRINTING OFFICE: 1977.H*h . 00 0, *+ 368 RgGIONNO .4 —fy-, i ■'

^NTEFlG^r COO-2990-6

INVESTIGATION OF METAL FLUORIDE THERMAL ENERGY STORAGE MATERIALS: AVAILABILITY, COST AND CHEMISTRY

Final Report

By J. L. Eichelberger

December 1976

Work Performed Under Contract No. EY-76-C-02-2990

Pennwalt Corporation Technological Center King of Prussia, Pennsylvania 19406

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