Molten Salt Chemistry - Part I

Total Page:16

File Type:pdf, Size:1020Kb

Molten Salt Chemistry - Part I B.A.R.C.-670 GOVERNMENT OF INDIA ATOMIC ENERGY COMMISSION MOLTEN SALT CHEMISTRY - PART I. PREPARATION OF CeF3, PuF3, ThF4 AND PURIFICATION OF LiF-BeFz-ThF4 MIXTURE by P. N. Iyer, R. Prasad, V. N. Vaidya, K. Nag, Z. Singh, D. D. Sood and M. V. Ramaniah Radiochemistry Division BHABHA ATOMIC RESEARCH CENTRE BOMBAY, INDIA B.A.R.C.-670 GOVERNMENT OP INDIA ATOMIC ENERGY COMMISSION o • PI MOLTEN SALT CHEMISTRY - PART I. PREPARATION OP CeF , PuP3, Th?4 AND HJRIPICATION OF LiP-BeP2-ThP4 MIXTURE by P.N. Iyer, R. Praead, V.W. Vaidya, K. Nag, Z. Singh, D.D. Sood and M.V. Ramaniah Radiochemistry Division BHA3HA ATOMIC RESEARCH CENTRE BOMBAY, INDIA 1973 ABSIRACT Equipment set up for the preparation of CBJ-, PUP* and and purification of LiF-BeF.-ThF. mixture for the determination of solubility of CeF, and PuF, in ternary Mixtures of LiF BBF -ThF. and binary mixtuiea of LiF-ThF. are described. Using 144 these equipment the preparation of 75 g of CeF., tagged with Ce and 60 g of PuF_ and purification of 1*2 kg of LiF-BeF.-ThF^ mixture have been carried out. The analysis of compounds for fluoride by pyrohydrolyais and ths estimation of Li, Be and Th in the salt mixture has been reported. MOLTEN SALT CHEMISTRY . PART I. PRLPAHATIUN OF CeF PuF,, ThF. AND PURIFICATION OF LiF-BeF -ThF. MIXTURE o *» 2 4 by. P.N. Iyer, R. Prasad, V.N. Vaidya, K. Nag, Z. Singh, O.O. Sood and M.V. Ramaniah 1 , INTRODUCTION Indian NuclBar Pouio? Programme is well under way with the commissioning of Tarapur Atomic Power Station and thg construction of Rnjasthan Atomic PoigBr Project and Madras Atomic Power Project in progress. As the next step in the reactor programme, various breeder concepts have been evaluated from the point of vieiu of economy and fuel utilisation and fast breeder reactor is onB of them. The Depart- ment of Atomic Energy is building a Fast Breeder Test Reactor at Madras. Another concept uihich looks promising is that of Molten Salt Breeder Reactor* It uias decided in 1967 to investigate the feasibility of using such a reactor for Indian Nuclear Power Programme with particular Bmphasis on the use of plutonium. The molten salt reactors are attractive on Bccount of their good potential for the utilisation of thorium and plutonium provided 233 PuF, is sufficiently soluble in the snlt matrix. Enriched uranium, U o and plutonium are the possible start up fissile materials for thesB 233 reactors. A .nolten salt reactor utilising U as the fissile material can have a conversion ratio greater than unity and it la termed a Molten Salt Breeder Reactor (MSBR) . ThB reactors utilising enriched uranium or plutonium as the start-up materials act as converters (con- version ratio less than 1) but change over to breeders with the 233.. 232_. - , , U- Th fuel cycle. Conceptual Molten Salt Breeder Reactors are thermal spectrum reactors which use fluorides of fissile materials dissolved in e suitable molten salt mixture as fuel. Graphite is used as the moderator. For the salt matrix, fluorine, lithium-7 and beryllium have been chosen ae major constituents because of their low neutron • lbourpLian cross-sections and also because of the reasonable solubility of fissile and fertile Fluoridoa in mixtures of lithium and beryllium fluorides at temparaturas of practical interest. The fertilB thorium as the tetrafluorida is dissol- ved in the fluoride salt matrix to form a separate blanket stream or diroctly added to the core salt itself. Tha reactor is fcormi-id ag a tuio- fluld reactor or single-fluid reactor accordingly. Currently the single- fluid, two region concept is being preferred at OHNL because it leads to comparable breeding and eliminates the necessity of using graphite as ••• plumbing material to separate salt streams. These reactors operate at about 1300 f and at atmospheric pressure. Hoat is transferred from the fuel salt to coolant salt in an lntormeidi nte heat exchanger., A outactic mixture of sodium f1'uoroborate and sodium fluoride is selected as the coolant salt. The coolant salt passes through a stream generator uhnrti au» critical steam is generated for power gonuration. Another side stream of the cora fuel is continuously passed through a chemical processing system for the separation of protactinium nnd fission products. As there is no QXCGSS ro-'ictiuity built in the ro.u-.tar, provision for continuous on-line refuelling j c m th. MnJ. Li.i-i Salt Brt.'udar Hcnc tur.'j li.iuc ii nuinbiT of adv.wiL. yra o\/::r l.lir othur rtijetor syatoms. Thuao are I. Lou specific inventory (approximately 1 kg/MUe) as comparad to other breeder reactor designs, II. Absence of material handling problems such as fuel fabrication etc., III. Possibility of in-lino fuol roproceocing, IU. High negative tempnr^iturQ coofficient or reactivity s-nd V. Absence of positiuo BXCODS rcuctiuity in the raactor. Somo of thG!3e features have boon brought out by the opnrat.lon of a 8 MU(t) Molten Snlh .Tmctor F.xpnrimf.nt at UiUlL. Thoro am of couroe a number of drawbacks c.lso in this reactor system Some of theoo are t 3 t 1) Need to pre-hsat tha equipment and to keep the equipment above ths malting point of tha salt mixture at all times, ii) Problem of long-term containment and recirculation of fuel, iii) Necessity for techniques of remote maintenance, it/} Problem of graphite damage at high power densities to be used in the reactor and v) Rigid requirement of leak tightness and component reliability. Extensive research and development work on all the aspects of Hoi ten Salt Reactor Technology has been in progress at Oak Ridge National Laboratory for more than 25 years and a recent review summarises the present status of this concept . The idea of using fusBd-fluorides as reactor fuel originated at OHNL and has been extensively studied since 1950* The basic feasibility of Buch a reactor system was demonstrated by the Aircraft Reactor Experiment (ARE) in 1954 whore NaF-ZrF.-UF. (53.1 - 40.7 - 6.2 mole pet) (2) 235 uias used as fuBlx '. Enriched uranium containing 93.4 pet U uas used. To test the types of fuels and equipment that mould be used in an MSBR the 0 Hlil(t) Molten Salt Reactor Experiment (MSRE) uas built and operated from Dune 1965* . This reactor operated at 1200 F and at atmospheric pressure. The initial fuel charge contained LiF-BBF_-ZrF^- UF. of composition 65 - 29 - 5 - 0.9 m/o and the uranium uas about 235 235 2Z% U. Tns molting point of the salt is 840°F. Operation with U as fuel uas terminated in March 1968. Uranium from the salt uas remove23d3 by fluorid^4B l volatility techniques and the reactor uas recharged with U as fuel* ' and operated from October 196B to December 1969. 233 The MSRE was the fir9t reactor in the world to operate on U fuel. tDurino demonstratg thB lase t thphase suitabilite of MSREy operatioof PuFn, aaboua a tmak 30a 0u gp ofuef PuFl fog r wa"SRs alsE o' added With the successful operation of MSRE the studies are nou directed towards development of MSBH. A number of designs for power reactor systems of this type have been proposed and evaluated at ORNL, Some of t 4 I tha designs are as follow9l A. Turn-region two-fluid MSBR 235^233^6) Iii thio design the fissile and fartile streams pass through asperate graphite tubes within the reactor core.. Same of *hs basic data fqr this reactor is as follows! Power 1000 Mlit(e) Fuel composition Blanket stream composition mole pet mol pet UF 63.60 LiF 71 BeF 32.1 BeF 2 ThF4 O.QO ThF4 - 27 UF 0.22 4 Breeding ratio - 1.05 Specific inventory 0.77 Kg/MU(o) B. Two-region two-fluid MS8R with protactinium removal Composition of fuel and blanket is Bame as in (A) Breeding ratio 1.07 Specific inuentory 0.68 KG/MW(e) C. One-fluid two-region W3BR In (A) and (B) tho use of graphite tubes in the reactor core posed serious problems and led to this concept. In this design the fissile and fertile materials are combined in one stream. Two regions are obtained by having different fuel- salt to moderator ratios in the inner and outer regions of the reactor. The central region is graph!to-moderated and is critical, whereas the outer region does not have any graphite and is sub- critical. ThB basic design data is as follows I Power 1000 MU(e) Fuel-cum-fartile salt composition mole pet LiF 71 .7 16 .0 ThF, 4 12 .0 t 5 i UF4 n.3 Breeding ratio 1.077 Specific inventory 1.6 Kg/NW(e) The concept (C) is the present favourite because It is technolo- gically simpler than the other two concepts. Though this design concept ie the best from the point of view of breeding gain and fuel inventory requirements! it envisages on-line reprocessing (which is not yet developed on an engineering scale) for the removal of protacti- nium and fission products and also requires replacement of core graphite every four years* As tha high performance MSBR»8 suffer from tha above dis- advantages, as an intermediate stage towards development of MSBR ( large HSRE type converters of 300 Mlil(e) and 1000 Wil(e) are being considered. These intermediate type of reactors envisage batch reprocessing for recovery of fissile material and discard of thB salt matrix with fission products and a core graphite life of 30 years* With addition of on- line reprcessing these reactors become breeders* The basic design data for a plutonium fuelled MSR with batch processing every 8 years and 30 year graphite life has fa sen published recently and is given b el out Pouer 300 MU)(e) Salt composition mole pet LiF 72 18 ThF4 10 Breeding ratio 0*84 Specific inventory 1.9 Kg/Hti/(e) ' .
Recommended publications
  • Environmental Health Criteria 126 Partially Halogenated Chlorofluorocarbons
    Environmental Health Criteria 126 Partially halogenated chlorofluorocarbons ( methane derivatives) Please note that the layout and pagination of this web version are not identical with the printed version. Chlorofluorocarbons, partially halogenated (methane derivatives) (EHC 126, 1991) INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY ENVIRONMENTAL HEALTH CRITERIA 126 PARTIALLY HALOGENATED CHLOROFLUROCARBONS (METHANE DERIVATIVES) This report contains the collective views of an international group of experts and does not necessarily represent the decisions or the stated policy of the United Nations Environment Programme, the International Labour Organisation, or the World Health Organization. Published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization Draft prepared by Professor D. Beritic-Stahuljak and Professor F. Valic, University of Zagreb, Yugoslavia, using texts made available by Dr. D.S. Mayer, Hoechst AG, Frankfurt am Main, Germany and by Dr. I.C. Peterson and Dr. G.D. Wade, ICI Central Toxicological Laboratory, Macclesfield, United Kingdom World Health Organization Geneva, 1991 The International Programme on Chemical Safety (IPCS) is a joint venture of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization. The main objective of the IPCS is to carry out and disseminate evaluations of the effects of chemicals on human health and the quality of the environment. Supporting activities include the development of epidemiological, experimental laboratory, and risk-assessment methods that could produce internationally comparable results, and the development of manpower in the field of toxicology. Other activities carried out by the IPCS include the development of know-how for coping with chemical accidents, coordination of laboratory testing and epidemiological studies, and promotion of research on the mechanisms of the biological action of chemicals.
    [Show full text]
  • Molten-Salt Reactor Chemistry
    MOLTEN-SALT REACTOR CHEMISTRY W. R. GRIMES Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 KEYWORDS: fused salt fuel, chemical reactions, reactors, beryllium fluorides, zirconium fluorides, Ii th i um fluorides, Received August 4, 1969 uranium hexafluoride, repro­ Revised October 7, 1969 cessing, protactinium, seporo­ tion pro c es s es, breeding, fission products, MSRE aggressive toward some otherwise suitable ma­ terial of construction and toward some suitable This document summarizes the large program of chemical research and development which led moderator material. The fuel must be stable to selection of fuel and coolant compositions for toward reactor radiation, must be able to survive the Molten-Salt Reactor Experiment (MSRE) and fission of the uranium (or other fissionable ma­ for subsequent reactors of this type. Chemical terial} and must tolerate fission product accumu­ lation without serious deterioration of its useful behavior of the LiF-BeFrZrFrUF4 fuel mixture and behavior of fission products during power op­ properties. We must also be assured of a gen­ uinely low fuel-cycle cost; this presupposes a eration of MSRE are presented. A discussion of low-cost fuel associated with inexpensive turn­ the chemical reactions which show promise for around of the unburned fissile material, and recovery of bred 233Pa and for removal of fission effective and economical schemes for recovery of product poisons from a molten-salt breeder reac­ tor is included. bred fissile material and for removal of fission­ product poisons from the fuel. A suitable secondary coolant must be provided to link the fuel circuit with the steam-generating equipment. The demands imposed upon this cool­ ant fluid differ in obvious ways from those im­ INTRODUCTION posed upon the fuel system.
    [Show full text]
  • 4340 Site-Wide Characterization Report
    4340 SITE-WIDE CHARACTERIZATION REPORT VOLUME 1 OF 5 PART I MARCH 1993 DOE-FN/EPA 400 REPORT 4340 SITE-WIDE CHARACTERIZATION REPORT -- - FERNALD ENVIRONMENTAL MANAGEMENT PROJECT FERNALD, OHIO REMEDIAL INVESTIGATION AND FEASIBILITY STUDY VOLUME 1 of 5 PART I MARCH 1993 U.S. DEPARTMENT OF ENERGY FERNALD FIELD OFFICE FINAL 01 4340 SITE-WIDE CHARACTERIZATION REPORT FERNALD ENVIRONMENTAL MANAGEMENT PROJECT FERNALD, OHIO REMXiIIAL INVESTIGATION AND FEASIBILITY STUDY VOLUME 1 of 5 PART I MARCH 1993 U.S. L;’:WARTMENTOF ENERGY FER NALD FIELD OFFICL FINAL 02 4340 NOTE TO READERS OF SWCR This final Site Wide Characterization Report is the product of several cycles of reviews and revisions, particularly concerning the methodologies used in the calculations of risks for the Preliminary Baseline Risk Assessment (PBRA) for the FEMP. The PBRA characterizes the current and potential threats to human health and the environment that may be posed by contaminants at the entire site. Many statistical and calculational methods, models, guidance documents, exposure scenarios, and pathways are utilized in deriving components of the site-wide risk. The PBRA was prepared in accordance with the Amended Consent Agreement . following the methodologies presented in the Risk Assessment Work Plan Addendum; however, differences in interpretation and application of the methodologies have resulted in departure from current EPA Region V guidance in some areas. The Site Wide Characterization Report fulfills the objective of providing a site-wide assessment of potential human health and environmental risks. As a result of discussions with, and additional guidance from EPA, the Operable Unit-specific Base1 ine Risk Assessments accompanying the Remedial Investigation reports for each OU will be prepared in accordance with the latest DOE/EPA agreements on risk assessment methodology.
    [Show full text]
  • Salts Purification and Redox Potential Measurement for the Molten Lif-Thf4-UF4 Mixture
    Proceedings of the First ACSEPT International Workshop Lisbon, Portugal, 31 March 2 April 2010 Salts purification and redox potential measurement for the molten LiF-ThF4-UF4 mixture V. Afonichkin, A. Bovet, V. Shishkin Institute of High-Temperature Electrochemistry 22, S.Kovalevskaya st.,Yekaterinburg, 620219,Russia Tel: 7-343-362-30-66, Fax: 7-343-374-59-92, e-mail: [email protected] Abstract The "dry" techniques of producing and clearing of some metals fluorides, their mixtures and cakes of a given composition obtained without usage gaseous HF for experiments under the Project ISTC #3749 are developed. The products of synthesizing and purification of oxygen-containing compounds, are studied by methods X-ray diffraction analysis, gravimetry or IR spectrometry. The experimental studies confirmed that solid NH4HF2 can be efficiently used instead of an unsafe and corrosive HF gas for removal of oxygen-containing impurities from metal fluorides and for conversion of uranium and thorium dioxides to anhydrous tetrafluorides. These processes do not require expensive equipment and special measures of safety. The electrochemical behavior of UF4 solutions in a melt 77LiF-23ThF4 (mole%) was studied by cyclic voltammetry. Formal analysis of the obtained dependencies showed that in our experimental conditions the recharge U(IV) to U(III) is qualitatively consistent with voltammetric criteria and can be classified as reversible. However, the results of mathematical processing of voltammograms show that the basic calculated characteristics of this reaction differ from the theoretical values corresponding one-electron process controlled by the diffusion rate. This indicates quasi-reversibility of the studied reaction. A. INTRODUCTION To prepare the molten salt mixtures, which are to be study is scheduled in Project #3749, use fluorides of metals with a minimum content of water and impurity oxides and/or oxyfluorides.
    [Show full text]
  • Experimental Studies of Actinides in Molten Salts
    LA-10340 UC-4 Issued: June 1985 LA—10340 DE85 015368 Experimental Studies of Actinides in Molten Salts James G. Reavis 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 responsi- bility fcr the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents 'hat its use would not infringe privately owned rights. Refer- ence herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recom- mendation, 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. Los Alamos National Laboratory Los Alamos, New Mexico 87545 !IT"ISUnOS OF THIS DOCUMENT IS ONLIMfTW t> EXPERIMENTAL STUDIES OF ACTINIDES IN MOLTEN SALTS by J. G. Reavis ABSTRACT This review stresses techniques used in studies of molten salts containing multigram amounts of actinides exhibiting intense alpha activity but little or no penetrating gamma radiation. The preponderance of studies have used halides because oxygen- containing actinide compounds (other than oxides) are generally unstable at high temperatures. Topics discussed here include special enclosures, materials problems, preparation and purification of acticide elements and compounds, and measurements of various properties of the molten volts. Property measurements discussed are phase relationships, vapor pressure, density, viscosity, absorption spectra, electromotive force, and conductance.
    [Show full text]
  • Toxicological Profile for Thorium
    f Toxicological Profile for Thorium September 2019 ***DRAFT – DO NOT CITE OR QUOTE – August 29, 2019*** Version 4.0 THORIUM ii DISCLAIMER Use of trade names is for identification only and does not imply endorsement by the Agency for Toxic Substances and Disease Registry, the Public Health Service, or the U.S. Department of Health and Human Services. THORIUM iii FOREWORD This toxicological profile is prepared in accordance with guidelines* developed by the Agency for Toxic Substances and Disease Registry (ATSDR) and the Environmental Protection Agency (EPA). The original guidelines were published in the Federal Register on April 17, 1987. Each profile will be revised and republished as necessary. The ATSDR toxicological profile succinctly characterizes the toxicologic and adverse health effects information for these toxic substances described therein. Each peer-reviewed profile identifies and reviews the key literature that describes a substance's toxicologic properties. Other pertinent literature is also presented, but is described in less detail than the key studies. The profile is not intended to be an exhaustive document; however, more comprehensive sources of specialty information are referenced. The focus of the profiles is on health and toxicologic information; therefore, each toxicological profile begins with a relevance to public health discussion which would allow a public health professional to make a real-time determination of whether the presence of a particular substance in the environment poses a potential threat to human health. The adequacy of information to determine a substance's health effects is described in a health effects summary. Data needs that are of significance to the protection of public health are identified by ATSDR.
    [Show full text]
  • Thorium Reactors, Thorium Infusion and Pressurized Water Reactor
    Department of Mechanical and Aerospace Engineering Research in to a thorium reactor, thorium infusion and pressurized water reactor Author: Torunn S. Hollingsaeter Supervisor: Cameron Johnstone A thesis submitted in partial fulfilment for the requirement of the degree Master of Science Sustainable Engineering: Renewable Energy Systems and the Environment 2018 Copyright Declaration This thesis is the result of the author’s original research. It has been composed by the author and has not been previously submitted for examination which has led to the award of a degree. The copyright of this thesis belongs to the author under the terms of the United Kingdom Copyright Acts as qualified by University of Strathclyde Regulation 3.50. Due acknowledgement must always be made of the use of any material contained in, or derived from, this thesis. Signed: Date: 23.08.2018 Abstract The aim for this thesis is to research positives and negatives of the use of thorium and different infusion options. First looking in to the history of the nuclear reactors which is the basis of what has become the reactors we know today and the start and end of the molten salt reactor research and experiments from the 50s to the 70s/80s. After the history it is looked in to the technical data and how a pressure water reactor works, named the APR1000 using the conventional uranium fuel cycle, as well as the molten salt reactor conceptual design from 1971 using the th-u233 fuel cycle and the option of infusing thorium in certain amount in to the existing light water reactors together with other elements.
    [Show full text]
  • Thf4, UF4, and Related Alkali Actinide Fluoride Systems
    PCCP View Article Online PAPER View Journal | View Issue Examination of the short-range structure of molten salts: ThF4,UF4, and related alkali actinide Cite this: Phys. Chem. Chem. Phys., 2021, 23, 11091 fluoride systems† a b a a c J. A. Oca´diz-Flores, A. E. Gheribi, J. Vlieland, D. de Haas, K. Dardenne, J. Rothe,c R. J. M. Konings ad and A. L. Smith *a The short-range structures of LiF–ThF4, NaF–AnF4, KF–AnF4, and Cs–AnF4 (An = Th, U), were probed using in situ high temperature Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy. Signally, the EXAFS spectra of pure molten ThF4 and UF4 were measured for the first time. The data were inter- Received 5th February 2021, preted with the aid of Molecular Dynamics (MD) and standard fitting of the EXAFS equation. As in related Accepted 23rd April 2021 4Àx studies, a speciation distribution dominated by [AnFx] (x = 7, 8, 9) coordination complexes was DOI: 10.1039/d1cp00566a observed. The average coordination number was found to decrease with the increasing size of the alkali cation, and increase with AnF4 content. An average coordination number close to 6, which had not been Creative Commons Attribution 3.0 Unported Licence. rsc.li/pccp detected before in melts of alkali actinide fluorides, was seen when CsF was used as solvent. 1 Introduction any intended application. Salt systems which have been subject of this type of analysis in the literature include AF–ZrF4 (A = Li, 7 8 9 10 Molten salts are a class of ionic liquids which have in recent Na, K), KF–ThF4, LiF–ThF4 and LiF–ThF4–UF4 systems.
    [Show full text]
  • Toxicological Profile for Thorium
    THORIUM 69 CHAPTER 4. CHEMICAL AND PHYSICAL INFORMATION 4.1 CHEMICAL IDENTITY Data pertaining to the chemical identity (that is, the common terms or symbols used for the identification of the element) of thorium are listed in Table 4-1. Table 4-1. Chemical Identity of Thorium and Compoundsa Thorium Thorium nitrate Thorium fluoride Characteristic Thorium dioxide (tetrahydrate) (tetrahydrate) Synonym(s)b and 232Th, thorium Thoria, No data Thorium tetrafluoride registered trade metal, Thorotrast name(s) pyrophoric Chemical formula Th ThO2 Th(NO3)4 ● 4H2O ThF4 ● 4H d Chemical Th O Th O O3N NO3 F F c structure Th . 4H2O Th . 4H2O O N NO F F 3 3 CAS Registry 7440-29-1c 1314-20-1c 13470-07-0 13709-59-6 Number Characteristic Thorium dicarbonate Thorium chloridee Thorium sulfatee Synonym(s)b and Thorium carbonatef Thorium tetrachloride; Thorium disulphate; sulfuric registered trade thorium(IV) chloride; thorium acid, thorium; thorium sulfate name(s) chloride; tetrachlorothorium nonahydrate; thorium sulfate 9water; thorium (IV) sulfate 9-water Chemical formula Th(CO3)2 ThCl4 Th(SO4)2·9H2O O C Th CO Chemical 3 3 structurec CAS Registry 19024-62-5 10026-08-1, 54327-76-3 10381-37-0 Number aAll information obtained from HSDB 1990, except where noted. bStructures are based on tetra valency of thorium unless otherwise stated. cCAS 1990. dSANSS 1988. eWeb_elements 2014a, 2014b. fNIH 2018. CAS = Chemical Abstracts Service THORIUM 70 4. CHEMICAL AND PHYSICAL INFORMATION 4.2 PHYSICAL AND CHEMICAL PROPERTIES The physical and chemical properties of elemental thorium and a few representative water-soluble and insoluble thorium compounds are presented in Table 4-2.
    [Show full text]
  • ORAU Team Document Number: ORAUT-TKBS-0017-2
    ORAU Team Document Number: ORAUT-TKBS-0017-2 NIOSH Dose Reconstruction Project Effective Date: 05/20/2004 Revision No.: 00 Technical Basis Document for the Fernald Environmental Controlled Copy No.: ______ Management Project (FEMP) – Site Description Page 1 of 83 Subject Expert: Samuel L.T. Chu Supersedes: Document Owner Approval: Signature on File Date: 05/13/2004 Terry A. Kuykendall, TBD Team Leader None Approval: Signature on File Date: 05/19/2004 Judson L. Kenoyer, Task 3 Manager Concurrence: Signature on File Date: 05/19/2004 Richard E. Toohey, Project Director Approval: Signature on File Date: 05/20/2004 James W. Neton, OCAS Health Science Administrator TABLE OF CONTENTS Section Page RECORD OF ISSUE/REVISIONS ....................................................................................................... 5 ACRONYMS AND ABBREVIATIONS .................................................................................................. 6 2.0 SITE DESCRIPTION .................................................................................................................. 7 2.1 Introduction ................................................................................................................................. 7 2.1.1 Site Background and History ........................................................................................... 8 2.1.2 Site Location and Facilities .............................................................................................. 8 2.1.3 Site Operations ...............................................................................................................
    [Show full text]
  • Investigation of Ionic Local Structure in Molten Salt Fast Reactor Lif-Thf4
    Investigation of ionic local structure in molten salt fast reactor LiF-ThF4-UF4 fuel by EXAFS experiments and molecular dynamics simulations Catherine Bessada, Didier Zanghi, Mathieu Salanne, Ana Gil-Martin, Mathieu Gibilaro, Pierre Chamelot, Laurent Massot, Atsushi Nezu, Haruaki Matsuura To cite this version: Catherine Bessada, Didier Zanghi, Mathieu Salanne, Ana Gil-Martin, Mathieu Gibilaro, et al.. Inves- tigation of ionic local structure in molten salt fast reactor LiF-ThF4-UF4 fuel by EXAFS experiments and molecular dynamics simulations. Journal of Molecular Liquids, Elsevier, 2020, 307, pp.112927. 10.1016/j.molliq.2020.112927. hal-03014065 HAL Id: hal-03014065 https://hal.archives-ouvertes.fr/hal-03014065 Submitted on 26 Nov 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Investigation of ionic local structure in molten salt fast reactor LiF-ThF4-UF4 fuel by EXAFS experiments and molecular dynamics simulations Catherine Bessada1*, Didier Zanghi1, Mathieu Salanne2, Ana Gil-Martin1,3, Mathieu Gibilaro4, Pierre Chamelot4, Laurent Massot4, Atsushi Nezu5, Haruaki Matsuura6 1CNRS, CEMHTI UPR3079, Univ. Orléans, F-45071 Orléans, France 2Sorbonne Univ., UPMC Univ. Paris 06, CNRS, PHENIX, F-75005 Paris- France 3 Enusa Industrias Avanzadas, S.A.
    [Show full text]
  • TOXICOLOGICAL PROFILE for THORIUM Agency for Toxic
    TOXICOLOGICAL PROFILE FOR THORIUM Agency for Toxic Substances and Disease Registry U.S. Public Health Service In collaboration with: U.S. Environmental Protection Agency October 1990 ii DISCLAIMER The use of company or product name(s) is for identification only and does not imply endorsement by the Agency for Toxic Substances and Disease Registry. 1 1. PUBLIC HEALTH STATEMENT The purpose of this statement is to provide you with information about thorium and to emphasize the human health effects that may result from exposure. At this time, thorium has been found at above background levels at 16 out of 1177 National Priorities List (NPL) hazardous waste sites. We do not know how many of the 1177 NPL sites have been evaluated for thorium. As EPA evaluates more sites, the number of sites at which thorium is found at above background levels may change. Because these sites are potential or actual sources of human exposure to thorium and because thorium may cause harmful health effects, this information is important for you to know. When a radioactive chemical is released from a large area such as an industrial plant, or from a container such as a drum or bottle, it enters the environment as a radioactive chemical emission. This emission, which is also called a release, does not always lead to exposure. You are exposed only when you come into contact with the radioactive chemical. You can come into contact with it in the environment through breathing air, eating, drinking, or smoking substances containing the radioactive chemical. Exposure may also result from skin contact with the radioactive chemical alone, or with a substance containing it.
    [Show full text]