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WILSON, Larry Eugene, 1935- DETERMINATION OF THE COMPOSITION OF SOLUTIONS OF BINARY MIXTURES BY TITRATION WITH WATER.

The Ohio State University, Ph.D., 1963 Chemistry, analytical

University Microfilms, Inc., Ann Arbor, Michigan DETERMINATION OF THE COMPOSITION OF SOLUTIONS OF

BINARY HYDROCARBON MIXTURES BY TITRATION

WITH WATER

DISSERTATION

Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University

By

LARRY EUGENE WILSON, B.Sc

The Ohio State University

1963

Approved by

Department of Chemistry ACKNOWLEDGMENT

The author wishes to express his sincere appreciation to Dr. Earle B. Caley for his encouragement and guidance throughout the course of this research.

ii CONTENTS

Page

INTRODUCTION . . . 1

HISTORICAL ...... 3

APPARATUS AND CHEMICALS ...... 17

A p p a r a t u s ...... 17

C h e m i c a l s ...... 19

EXPERIMENTAL PROCEDURES ...... 25

Aromatic Hydrocarbon Mixtures ...... 25

Aliphatic Hydrocarbon Mixtures ...... 29

EXPERIMENTAL D A T A ...... 31

EXPERIMENTAL RESULTS ...... 138

Precision of Results— Aromatic Mixtures ...... 138

Accuracy of Results— Aromatic Mixtures ...... 1^2

Precision and Accuracy of Results— Aliphatic Mixtures...... 150

THEORETICAL CONSIDERATIONS ...... 15^

SUMMARY ...... 156

BIBLIOGRAPHY ...... 158

AUTOBIOGRAPHY ...... 160 l i s t o f t a b l e s

Table Page

I Results of Siggia and Hanna for analysis of acetic acid-carbon tetrachloride-water mixtures...... 8

II Results of Jones and Amstell for water content of methanol ...... 9

III Comparison of experimental indices of refraction to theoretical values ...... 23

IV Titration of mesitylene-benzene-etnanol mixtures having a total dilution volume of to.OO mL / ...... 33

V Titration of mesitylene-benzene-ethanol mixtures having a total dilution volume of 50.00 ml...... 33

VI Titration of p-cymene-benzene-ethanol mixtures having a total dilution volume of 40.00 ml...... 38

VII Titration of p-cymene-benzene-ethanol mixtures having a total dilution volume of 50.00 ml...... 38

VIII Titration of xylene-benzene-ethanol mixtures having a total dilution volume of 4-0.00 ml. 43

IX Titration of xylene-benzene-ethanol mixtures having a total dilution volume of 50.00 ml. 43

X Titration of mesitylene-toluene-ethanol mixtures having a total dilution volume of 40.00 ml...... 48

XI Titration of mesitylene-toluene-ethanol mixtures having a total dilution volume of 50.00 ml...... 48

XII Titration of p-cymene-toluene-ethanol mixtures having a total dilution volume of 40.00 ml...... 53 iv LIST OF TABLES— (Continued)

Table Page

XIII Titration of p-cymene-toluene-ethanol mixtures having a total dilution volume of 50.00 ml...... 53

XIV Titration of mesitylene-benzene-isopropanol mixtures having a total dilution volume of *1-0.00 ml...... 58

XV Titration of mesitylene-benzene-isopropanol mixtures having a total dilution volume of 50.00 ml...... 58

XVI Titration of p-cymene-benzene-isopropanol mixtures having a total dilution volume of 40.00 ml...... 65

XVII Titration of p-cymene-benzene-isopropanol mixtures having a total dilution volume of 50.00 ml...... 65

XVIII Titration of xylene-benzene-isopropanol mixtures having a total dilution volume of 40.00 ml...... 68

XIX Titration of xylene-benzene-isopropanol mixtures having a total dilution volume of 50.00 ml...... 68

XX Titration of mesitylene-toluene-isopropanol mixtures having a total dilution volume of 40.00 ml...... 75

XXI Titration of mesitylene-toluene-isopropanol mixtures having a total dilution volume of 50.00 ml...... 75

XXII Titration of p-cymene-toluene-isopropanol mixtures having a total dilution volume of 40.00 ml...... 78

XXIII Titration of p-cymene-toluene-isopropanol mixtures having a total dilution volume of 50.00 ml...... 78

XXIV Titration of mesitylene-benzene-methanol mixtures having a total dilution volume of 50.00 ml...... 85

v LIST OF TABLES— (Continued)

Table Page

XXV Titration of raesitylene-benzene-methanol mixtures having a total dilution volume of 60.00 ml...... 83

XXVI Titration of p-cymene-benzene-methanol mixtures having a total dilution volume of 50.00 ml...... 88

XXVII Titration of p-cymene-benzene-methanol mixtures having a total dilution volume of 60.00 ml. 88

XXVIII Titration of xylene-benzene-methanol mixtures having a total dilution volume of 50*00 ml. 93

XXIX Titration of xylene-benzene-methanol mixtures having a total dilution volume of 60.00 ml. 93

XXX Titration of mesitylene-toluene^methanol mixtures having a total dilution volume of 50.00 ml...... 98

XXXI Titration of mesitylene-toluene-methanol mixtures having a total dilution volume of 60.00 ml...... 98

XXXII Titration of p-cymene-toluene-methanol mixtures having a total dilution volume of 50.00 ml. .'...... 103

XXXIII Titration of p-cymene-toluene-methanol mixtures having a total dilution volume of 60.00 ml...... 103

XXXIV Titration of n--n--isopropanol mixtures having a total dilution volume of 50.00 ml...... 108

XXXV Titration of n-decane-n--isopropanol mixtures having a total dilution volume of 50.00 ml...... 109

XXXVI Titration of n-decane-n--isopropanol mixtures having a total dilution volume of 50.00 ml...... 109

XXXVII Titration of n-decane-2 methylpentane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 112

vi LIST OF TABLES— (Continued)

Table Page

XXXVIII Titration of n-decane^^,^ trimethylpentane- isopropanol mixtures having a total 1 dilution volume of 50.00 ml...... 112

XXXIX Titration of n--n-decane-isopropanol mixtures having a total dilution volume of 50.00 ml...... 115

XL Titration of n-dodecane-n-octane-isopropanol mixtures having a total dilution volume of 50.00 ml...... 115

XLI Titration of n-tetradecane-n-decane-isopropanol mixtures having a total dilution volume of 50.00 ml...... 116

XLII Titration of n-tetradecane-n-octane-isopropanol mixtures having a total dilution volume of 50.00 m l ...... 116

XLIII Titration of n-decane-3 methylpentane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 119

XLIV Titration of n-decane-2,3 dimethylpentane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 119

XLV Titration of n-decane-2,3 dimethylbutane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 119

XLVI Titration of n-decane-2,2,3 trimethylbutane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 122

XLVII Titration of n-decane-3 methylhexane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 122

XLVIII Titration of n-decane-3 methylheptane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 123

XLIX Titration of n-decane-2,2 dimethylbutane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 123

vii LIST OF TABLES— (Continued)

Table Page

L Titration of n-dodecane-3 methylpentane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 126

LI Titration of n-dodecane-5 methylhexane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 126

LII Titration of n-tetradecane-2 methylpentane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 127

LIII Titration of n-tetradecane-3 methylheptane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 127

LIV Titration of n-heptane-2,2,3 trimethylbutane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 130

LV Titration of n-heptane-2,3 dimethylpentane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 130

LVI Titration of 3 methylheptane-2 methylpentane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 131

LVII Titration of 3 methylheptane-2,3 dimethyl- -isopropanol mixtures having a total dilution volume of 50.00 ml...... 131

LVIII Titration of 3 methylhexane-2 methylpentane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 13^

LIX Titration of n-hexane-2,2 dimethylbutane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 13^

LX Titration of n-heptane-n-hexane-isopropanol mixtures having a total dilution volume of 50.00 ml...... 135

LXI Titration of n-octane-2,2,^ trimethylpentane- isopropanol mixtures having a total dilution volume of 50.00 ml...... 135

viii LIST OF TABLES— (Continued)

Table Page

LXII Summary of the degree of precision as a function of volume of aromatic hydrocarbon- ethanol titrations ...... 139

LXIII Summary of the degree of precision as a function of volume of aromatic hydrocarbon- isopropanol titrations ...... ibO

LXIV Summary of the degree of precision as a function of volume of aromatic hydrocarbon- methanol t i t r a t i o n s ...... l*tl

LXV Summary of the degree of precision as a function of per cent composition of aromatic hydrocarbon-ethanol titrations . . 1^3

LXVI Summary of the degree of precision as a function of per cent composition of aromatic hydrocarbon-isopropanol titrations ikk

LXVII Summary of the degree of precision as a function of per cent composition of aromatic hydrocarbon-methanol titrations . . 1^5

LXVIII Absolute errors for mesitylene-benzene- ethanol mixtures caused by 0.10 ml. end point e r r o r ...... 1^7

LXIX Absolute errors for mesitylene-benzene- isopropanol mixtures caused by 0.10 ml. end point e r r o r ...... 1^8

LXX Summary of the degree of precision as a function of per cent composition of titra­ tion of aliphatic hydrocarbon-isopropanol mixtures all with a total dilution volume of 50.00 ml...... 151

LXXI Summary of the degree of precision for sill titrations of binary hydrocarbon mixtures . 153

ix LIST OF FIGURES

Figure Page

1 General schematic of the all Pyrex dispensing apparatus used in measuring and transferring absolute ethanol to the titration cell . . . 20

2 Titration curves of mesitylene-benzene-ethanol mixtures having a total dilution volume of 40.00 ml...... 34

3 Titration curves of mesitylene-benzene-ethanol mixtures having a total dilution volume of 50.00 ml...... 36

k Titration curves of p-cymene-benzene-ethanol mixtures having a total dilution volume of 40.00 ml...... 39

5 Titration curves of p-cymene-benzene-ethanol mixtures having a total dilution volume of 50.00 ml...... 4l

6 Titration curves of xylene-benzene-ethanol mixtures having a total dilution volume of 40.00 ml...... 44

7 Titration curves of xylene-benzene-ethanol mixtures having a total dilution volume of 50.00 ml...... 46

8 Titration curves of mesitylene-toluene-ethanol mixtures having a total dilution volume of 40.00 ml...... 49

9 Titration curves of mesitylene-toluene-ethanol mixtures having a total dilution volume of 50.00 ml...... 51

10 Titration curves of p-cymene-toluene-ethanol mixtures having a total dilution volume of 40.00 ml...... 54

11 Titration curves of p-cymene-toluene-ethanol mixtures having a total dilution volume of 50.00 ml...... 56 x LIST OF FIGURES— (Continued)

Figure Page

12 Titration curves of mesitylene-benzene- isopropanol mixtures having a total dilution volume of 40.00 m l ...... 59

13 Titration curves of mesitylene-benzene- isopropanol mixtures having a total dilution volume of 50*00 ml...... 6l

14 Titration curves of p-cymene-benzene-isopropanol mixtures having a total dilution volume of 40. 00 ml...... 64

15 Titration curves of p-cymene-benzene-isopropanol mixtures having a total dilution volume of 50.00 ml...... 66

16 Titration curves of xylene-benzene-isopropanol mixtures having a total dilution volume of 40,00 ml...... 69

17 Titration curves of xylene-benzene-isopropanol mixtures having a total dilution volume of 50.00 ml...... 71

18 Titration curves of mesitylene-toluene- isopropanol mixtures having a total dilution volume of 40.00 ml...... 74

19 Titration curves of mesitylene-toluene- isopropanol mixtures having a total dilution volume of 50.00 ml...... 76

20 Titration curves of p-cymene-toluene- isopropanol mixtures having a total dilution volume of 40.00 ml...... 79

21 Titration curves of p-cymene-toluene- isopropanol mixtures having a total dilution volume of 50.00 ml...... 8l

22 Titration curves of mesitylene-benzene- methanol mixtures having a total dilution volume of 50.00 ml...... 84

23 Titration curves of mesitylene-benzene- methanol mixtures having a total dilution volume of 60.00 ml...... 86

xi LIST OF FIGURES— (Continued)

Page

24 Titration curves of p-cymene-benzene-methanol mixtures having a total dilution volume of 50.00 ml...... 89

25 Titration curves of p-cymene-benzene-methanol mixtures having a total dilution volume of 60.00 ml...... 91

26 Titration curves of xylene-benzene-methanol mixtures having a total dilution volume of 50.00 ml...... 94 j* 27 Titration curves of xylene-benzene-methanol mixtures having a total dilution volume of 60.00 ml...... 96

28 Titration curves of mesitylene-toluene-methanol mixtures having a total dilution volume of 50.00 ml...... 99

29 Titration curves of mesitylene-toluene-methanol mixtures having a total dilution volume of 60.00 ml...... 101

30 Titration curves of p-cymene-toluene-methanol mixtures having a total dilution volume of 50.00 ml...... 104

31 Titration curves of p-cymene-toluene-methanol mixtures having a total dilution volume of 60.00 ml...... 106

52 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml...... 110

33 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml...... 113

34 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml...... 117

Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml...... 120

xii LIST OF FIGURES— (Continued)

Figure Page

36 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50*00 ® 1 ...... 124

37 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml # ...... 128

38 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml...... 132

39 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml...... 136

xiii INTRODUCTION

When sufficient water is added to a solution which con­ sists of a liquid miscible with water and one or more liquids of limited solubility in water a phase separation occurs. This separation results in the appearance of a pronounced turbidity and occurs generally upon the addition of only one drop of water at the end point when the solution is stirred with suf­

ficient rapidity to cause intimate dispersion of the two phases

into each other. The volume of water that is required to pro­

duce this turbidity depends upon the nature and the concen­

trations of the components of the system. Therefore, if the

addition of water is done with a buret an accurate titration of

the system can be performed.

In this investigation the above considerations were ap­ plied to a quantitative determination of the composition of binary mixtures of liquid . The method consisted of the preparation of synthetic binary mixtures of hydrocarbons

followed by the addition of a definite volume of alcohol. The alcohol used in the investigations was either absolute ethanol, absolute methanol, or isopropanol. The volume of water required

to cause permanent turbidity was then determined.

This general technique of addition of water to the ap­ pearance of turbidity has been widely used by physical chemists 2 for the study of ternary solubility relationships between two organic liquids and water. There have been some analytical applications of this method but much of the work was such that quantitative information was either not of great accuracy or not easily obtained from the results of a simple titration. HISTORICAL

/

The general technique of adding water to a solution of two organic liquids, one of which is miscible in water, and using the appearance of turbidity as an indicator, has been widely used for the determination of ternary solubility diagrams.

A procedure commonly followed for this purpose was that used by Holt and Bell'*' on the system m-xylene-ethanol- water. In this method a known volume of the organic liquid immiscible with water was taken and successive equal small portions of the organic liquid miscible with water were added. After each addition of the second liquid, water was added until a distinct turbidity was produced through separation of a second phase in minute drops. The mixture was kept at constant temperature and was shaken repeatedly or stirred mechanicsilly. These data were then plotted on a triangular axis.

■*Holt, Alfred, and Bell, Norman M., J. Chem. Soc., 105 (191*0, pp. 633-9. A similar procedure, based on accurate weights of the 2-11 components, was used by Washburn and coworkers in a series of papers on the study of solubility relationships for ternary mixtures consisting of water, a lower aliphatic alcohol, and a hydrocarbon. Alcohols used in their research were methanol,

ethanol, isopropanol, t-butanol, and n-propanol. Hydrocarbons used were benzene, toluene, cyclohexane, and cyclohexene. All the ternary solubility diagrams were made at constant temper­ ature.

A similar study, involving the straight chain hydro- 12 carbon, hexane, was undertaken by Tarasenkov and Paul’sen.

An organic solvent which is mutually soluble with water and an organic liquid can also be used for a titration of a

2 Washburn, E. R., Hnizda, V., and Void, R. D., J. Am. Chem. Soc., 53 (1931), p p . 3237-*0. ^Washburn, E. R., and Void, R. D., ibid., 5^ (1932), pp. **217-25. Washburn, E. R., and Spencer, H. C., ibid., 56 (193*0, pp. 36l-*f. ^Washburn, E. R., and Olsen, A. L., ibid., 57 (1935), pp. 303-5. ^Washburn, E. R., and Mason, L. S., ibid., 59 (1937), pp. 2076-7. 7 Washburn, E. R., Beguin, A. E., and Bechord, 0. C., ibid., 61 (1939), PP. l69*f-5. g Washburn, E. R., and Beguin, A. E., ibid., 62 (19**0), pp. 579-81. 9______., ibid., 62 (19**0), pp. l**5**-7. ■^Washburn, E. R., Brockway, C. E., Graham, C. L., and Deming, P., ibid., 6k (19**2), pp. 1886-8 . ^Washburn, E. R., and Simonsen, D. R., ibid., 68 (l9*+6 ), pp. 235-7. 12 Tarasenkov, D. N., and Paul'sen, I. A., Zhur. Obshchei Khim., 7 (1937), PP* 21**3-8. heterogeneous mixture of water and a hydrocarbon. Walton and 13 Jenkins applied this procedure in a study of the ternary solubility of a toluene-acetone-water mixture. They took 10 ml. of either water or toluene in a titration cell, added a small amount of the other immiscible liquid, and titrated with acetone until the turbidity just cleared. These authors also proposed the detection of the end point as that point at which a bright object placed directly behind the titration vessel became sharply defined.

Another general technique used for the determination of 14- ternary solubility data was that used by Sidgwick and Spurrell sind involved the determination of the criticsil solution tem­ perature of ternary mixtures. This solubility information was obtained by the preparation of synthetic mixtures of benzene, ethanol, and water and determining the temperature at which the benzene crystallized out.

Although all the above examples except one utilized the appearance of turbidity as an indicator for a titration with water, none of the work was done for the purpose of quantitative determination of the composition of a mixture. 15 Bogin appears to be the first to use an analytical procedure in which water was used as a titrant. The procedure consisted of the addition of water to a given simount of sample

■^Walton, J. H., and Jenkins, J. D., J. Am. Chem. Soc., 45 (1923), P. 2559. 14 Sidgwick, N. V., and Spurrell, W. J., ibid., 117 (1920), pp. 1397-1404. ■^Bogin, G. D., Ind. Eng. Chem., 16 (1924), pp. 38O-6 . 6 until turbidity first appeared. The temperature of the solution was taken and the composition of the original mixture was found by reference to a series of standard curves prepared from titrations of known solutions at various temperatures.

With butanol-ethanol mixtures Bogin found that direct determination was only accurate for 25-50 per cent ethanol.

However, up to 60 per cent ethanol could be determined by use of 5 per cent sodium chloride solution as a titrant and up to

85 per cent ethanol could be determined by titration with 20 per cent sodium chloride. In benzene-ethanol mixtures the ef­ fective range was between 50 and 90 per cent ethanol.

Bogin determined the composition of ethanol-water mixtures by titration with butanol. He also demonstrated that a ternary mixture such as acetone-butanol-ethanol could be analyzed by a combination of a chemical determination of the acetone present and a titration with water to the appearance of turbidity.

This combination of a physical titration with water and a chemical determination of one of the components was also used by Siggia and Hanna‘S for the determination of the composition of various ternary systems containing two mutually immiscible components and a solvent in which both were soluble.

In this method one of the mutually immiscible com­ ponents was determined chemically. A separate sample was

^Siggia, S., and Hanna, J. G., Anal. Chem., 21 (19^9)» pp. 1086-9. titrated with one or the other of the mutually immiscible com­ ponents until a turbidity resulted.

The titration to turbidity brings the composition of the sample onto the curve in the ternary solubility phase

diagram for the particular system involved. The chemical de­

termination of the one component establishes the point on the curve. This point corresponds to the composition of the sample after titration to turbidity. The amount of titrant added is measured and is subtracted from the total which is indicated

from the composition of the original sample.

One of the systems investigated in this manner was acetic acid-carbon tetrachloride-water. The acetic acid was determined by a direct titration with standard base and the sample was brought to turbidity by the addition of water. Although the precision of these titrations was good the relative errors were sometimes considerable as is shown in Table I.

The sensitivity to critical solution temperature of 17 methanol-cyclohexane mixtures was utilized by Jones and Amstell

for the determination of trace amounts of water in methanol.

The optimum condition for sensitivity was found to be a 75~25 per cent by weight ratio of cyclohexane-methanol. With this concentration ratio the critical solution temperature of the mixture was found to vary greatly for water content up to 3,9

17 Jones, D. C., and Amstell, S., J, Chem. Soc,t (1930)» pp. 1316-23. TAELE I RESULTS OF SIGGIA AND HANNA FOR ANALYSIS OF ACETIC ACID-CARBON TETRACHLORIDE-WATER MIXTURES

% Acetic Acid % Carbon Tetrachloride % Water

Sample Found Present Rel. Error Found Present Rel. Error Found Present Rel. Error

1 86.0 85.49 +0.60 10.3 9.66 + 6.63 3.46 4.82 -28.22

2 77.0 76.69 +0.40 18.7 18.48 + 1.19, 4.21 4.94 -14.78

3 67.8 67.33 +0.70 30.6 30.69 - 0.29 1.56 1.95 -20.00

4 52.2 52.27 -0.13 47.1 47.22 - 0.25 0.72 1.00 -28.00

3 76.3 75.79 +0.67 4.04 4.85 -16.70 19.70 19.44 + 1.32

00 per cent. Table II shows the miscibility temperatures for varying water contents of methanol*

TABLE II RESULTS OF JONES AND AMSTELL FOR WATER CONTENT OF METHANOL

Water Content Miscibility Temperature % 0° C.

0.00 45.55 0.331 50.52 0.800 55.74 1.114 58.75 2.051 66.50 3.900 81.56

Robertson by a similar method determined up to 2 per cent water in ethanol by use of dicyclohexyl. The optimum ratio found for this purpose was 1:2 alcohol-dicyclohexyl, 19 Spiridonova determined the quantitative composition of a binary solution of an organic solid in an organic solvent by the addition of water until the organic solid separated from the solution and caused cloudiness or turbidity. The systems studied were binary mixtures of camphor, borneol, or naphthalene in 20 ethanol and acetone solutions. Spiridonova next applied this method to the determination of the aqueous strengths of ethanol, ' n Q Robertson, G. R., Ind. Eng. Chem. Anal. Ed., 15 (19^3), pp. 451-2. 19 Spiridonova, S. I., Zhur. Obshchei Khim., 7 (1937), pp. 1071-81. 20 ______Zhur. Priklad. Khim., 13 (1940), pp. 1169-77* PLEASE NOTE: Pages 10 and 11 are poor carbon copy. Filmed as received.

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X • 0* o*"y 1 1 2 whoro X lo tho voloao porooatago of wator ia tho uakaowa, V io tho oolaao of wator roqairod to titrato tho uakaowa* aad aad ?2 oro tho tolwaoo of wator roqairod to titrato oaaploa ooatalalag 0 aad 0 oolaao par ooat roopootivoly* Ho oiaiaod a rolatioo orror of not ooor • 2 por ooat for tho raago 0*20 oolaao por ooat wator

^Splrldoaooa, S. X*, ibid*, lb (19^1)* pp. 6b6-51. U m i * * W <19b€), pp. 966*72. u la athaaol* Howavar, hia total dlffarenas la titration valuoa batwaaa 0 and 20 par aaat uator la athaaal uaa only 0*690 nl* M « (ava a asnaltlvity of only 0 *0>% al* par par aaat water ooatant*

Spiridonova*^* aaat dataralnad the eoapoaltloa of binary alxtvraa of aartala alcohols* ketones, and sstsra* la thla proaadara aa equal volaaa of furfural aaa addad to tha binary uixture and water aaa delivered froa a alarobarat aatll turbidity appeared* Sana af thaaa Mixtures vara aethanol* aaatoaa la the range 0-10 par aaat aethaaol* acetoae*nethyl aaatata la tha r u g a 0*10 par aaat aethyl acetate* aethaaol* aatbyl aaatata la tha range 0*39 por aaat aatbyl aaatata* aad athaaol*laaaayl alaohol la tha dlluta laaaayl alcohol range* Tha praalaloa of tha tltratleaa aaa about 2*9 par aaat* 26 Za tha latar payor* Spiridonova published addltloaal data for fcoaagaaaoua tuo*aoapoaaat alxturoa* utilising furfural* aaapbor* aad boraool aa Indicators* Spiridonova also dataralnad tha atroagtha of aolutloaa of al act rolytoo by physloal titrations* la a titration with uatsr uaiag ltl sttiaaol*laobutaaol aa aa Indicator* Spiridonova*^ dataralnad tha ahlorlda aoaaaatratloa in aa aqueous solution*

i5Splrldo»oT., s. i„ ii>l«.. 20 (1997). pp. 655-91. * itta.. a U 9*B), pp. 998-5 5 . 2___ •• Brnri ‘iiiii me- * uw). pp. 1*9-7 2 . " •• » ■ > . «*«-- 2* <1954), pp. 1627-55. ” ______•• Zlur. m U .. 45 (1954), pp. 949-5*. 12 2g PQ Spiridonova * also determined the strengths of aqueous in­ organic electrolytes by titration with 95 per cent ethanol. The salts served as their own indicators due to their salting-out effects.

In the last of the papers by Spiridonova^, some gener­ alities on the selection of indicator concentrations were set forth. The use of acetoacetic esters, acetyl-acetone and iso- butyric acid as turbidity indicators was also proposed.

Kimura^ published what he described as new methods for determining small amounts of water in ethanol and in pyridine solutions. However, these methods were the same as Spiridonova’s except that carbon tetrachloride was used as the turbidity indicator. '

Kimura added 10 ml. of carbon tetrachloride to a 10 ml. sample of aqueous ethanol and titrated with water to turbidity.

An equation for computing the results was developed which has the considerable merit of allowing corrections to be made for titra­ tions made at other than a standard temperature. For those ti­ trations made at the standard temperature of 25°C., the equation used was:

y (2.03 ~ V 100) 10 ’

pQ Spiridonova, S. I., ibid., 22 (1949), pp. 1284-91. 2 9______., Zhur. Fiz. Khim., 29 (1955), pp. 159-65. 30 Spiridonova, S. I., and Nikitin, E. K., C. A ., 55 (1959), p. 9788; Izvest. Vysshykh Ucheb. Zavedenii Khim. i Khim. Teknol., (1958), pp. 22-7. ^Kimura, T., C. A., 47 (1955), p. 5844; Ann. Repts. Takeda Research Lab., 11 (1952), pp. 61-73. 13 where X is the per cent water by volume in the original solution and V is the ml. of water required to give turbidity. At tem­ peratures below 25°C. the equation was:

[2.03 - 0.03 (25 - t°) - V] • 100 * = 10 and at temperatures above 25°C. it was:

v [2.03 + 0.03 (t° - 25) ~ V3 • 100 10 32 Hodgson and Clover devised a method for determining the composition of a ternary mixture of ethanol, ethyl ether, and water by measuring the boiling point of the mixture, adding dibutyl phthalate, and titrating with water to a permanent tur­ bidity. The quantitative composition was then found by reference to standard calibration graphs based on solutions of known com­ position treated in the same way.

Another method for analysis of ternary systems was devised 33 by Smith . This method depended upon two titrations to either turbidity end points or miscibility end points.

One of the ternary mixtures analysed by this method was ethanol-benzene-watero When the mixture was homogeneous, water was added until it became turbid. Additional water was added and the system was brought back to miscibility by titration with ethanol. When the mixture was rich in water, benzene was added and the mixture titrated with ethanol to miscibility. Additional

•^Hodgson, H. W., and Clover, J. H., • Analyst. 76 (1951), pp. 635-^3. ^Smith, A. S., Ind. Eng. Chem., 37 (19^5)» pp. l85-7» benzene was added and the system was again titrated to miscibility with ethanol. By calculations and reference to standard curves, the composition of the original mixture could be determined.

All of the previous cited investigations have left some­ thing to be desired. Very little of the work utilized exact measurements on the system for the purpose of quantitative deter­ minations. In nearly every investigation which was made with quantitative analysis in mind, the volume of water added to reach turbidity was small and the difference in titrant values over the range of composition studied was in each case very small. This necessitated the use of a microburet and frequently small normal end point errors resulted in very large relative errors in com­ position.

There is also little or no evidence of careful control of temperature in most of the previous work. In only one paper was the magnitude of the temperature effect on solubility studied. 3b 35 Habboush ’ in her Ph.D. dissertation studied certain of these shortcomings in the previous work. In her investigation, the physical titration method was extended to classes of organic compounds not previously studied. Those mixtures investigated were aromatic hydrocarbon-alcohol, ester-alcohol, ether-alcohol, and amine-alcohol. The effect of temperature was studied by

3b Habboush, A., "Determination of the composition of mixtures of organic liquids by physical titration with water," (Ph.D. dissertation, Dept, of Chemistry, The Ohio State Uni­ versity, 1959)* ^Caley, E. P., and Habboush, A., Anal. Chem., 33 (l96l), pp. 1613-1 6 . 15

titrating mixtures at 15°» 20°, 25°, and 30°C. In general, an

increase in titrant volume of about 7*5 per cent over a five

degree range of temperature was found. Although the effect of

temperature was studied, there does seem to be some chance of

error in the method by which this was done. At no time was the

temperature of the solution actually measured. The solution was

initially allowed to come to equilibrium by placing it in the

water bath for about 15 minutes prior to the start of the titra­

tion. Then the titration was performed slowly with an addition

of not greater than 2 ml. per minute to allow the dissipation of

heat which is generated due to the hydrogen-bond formation during

the dilution of alcohol. For some titration volumes reported,

it is questionable whether the temperature of the solution was

exactly at the desired value when the titration was completed.

Habboush also recommended the use of solid iodine as sin

aid in end point detection. This did make the appearance of

turbidity much more evident as it is much easier to see a clear

orange solution become turbid while immersed in an illuminated

water bath than to see a clear colorless solution become turbid

under the same conditions.

The curves obtained by titration of hydrocarbon-alcohol mixtures were found to obey with only relatively small errors an

equation of the type:

log10X = A + By + ° log10y where X is the percentage by volume of the component that is slightly soluble in water, y is the volume of water in milliliters required for titration, and A, B, and C are constants that depend on the temperature, the volume of sample, and the characteristics of the particular system. This equation was based on three selected points along the curve. It was reported that although the results computed by means of this equation might be suf­ ficiently accurate for practical purposes, they were less ac­ curate than those found by the use of large standard curves or detailed tables. The advantage was that only three standard solutions needed to be titrated.

The possibility of determining the composition of binary organic mixtures by dilution with ethanol and subsequent titration with water to turbidity was also investigated by Habboush. How­ ever, this was not done systematically and only a single con­ centration was studied in each case. In general, the concen­ trations which were selected did not give a large enough differ­ ence in titration volumes to allow significant quantitative results to be obtained.

In view of the shortcomings in previous work it seemed desirable to study in a more thorough manner the determination of the composition of binary hydrocarbon mixtures by dissolving them in different alcohols and titrating with water. APPARATUS AND CHEMICALS

Apparatus

Titration cell*— The titration cell consisted of a 180 ml. lipless electrolytic beaker. The cell was fitted with a tight fitting rubber stopper into which three holes had been drilled.

One of these holes was used for insertion of an electrically driven glass stirrer. A calibrated thermometer was inserted tightly into the second hole. The third hole was used for the buret tip. The cell was supported in the water bath by a metal ring attached securely to the frame of the water bath. This allowed freedom to raise and lower the titration cell into the water bath.

Buret.— The buret used in all titration was a 50 milli­ liter Exax blue line buret calibrated in the normal manner. The buret was provided with a water jacket k centimeters in diameter which enveloped it from above the zero mark nearly to the stop­ cock. An elongated offset tip was sealed below the stopcock in order to allow room for both the buret and the stirrer motor.

This tip was drawn out so that the size of water drops from it would not exceed 0.03 ml.

Water bath, temperature control, and circulator .--The water bath was 12 inches in diameter by 11 inches high. The bath was illuminated with a circular fluorescent lamp which was located

17 within the base of the water bath. This lamp made possible easier observance of the turbidity at the end point. The tem­ perature regulator was a Model SW Thermonitor manufactured by

E. H. Sargent and Company. A thermistor served as the temper­ ature sensing device. The heaters and water circulator were self-contained in the water bath tower and were connected into the circuit of the Thermonitor. These heaters enabled the rapid attainment of operating temperature. The water from the bath was circulated by means of rubber tubing through the water-jacket of the buret by use of a small water pump. Because of the heat evolved by the fluorescent lamp located directly below the water bath and because the room temperature was at times greater than the operating temperature of the bath, it was necessary to cir­ culate part of the water through a cooling device. This device consisted of a porcelain crock containing a copper coil and filled with crushed ice. This coil was connected by rubber tubing to the water pump, thereby becoming part of the circu­ lation system. The water could then be drawn from the bath and either circulate through the cooling coil into the jacket of the buret and back into the water bath or it could by-pass the cooling coil by means of a simple valve and enter the buret jacket directly. This valve also could be used to pass any fraction of the water through the cooling coil needed to maintain the proper operating temperature of the bath.

Sample dispensing burets.— For the preparation of the binary mixtures one component, designated as A in the tables, was dispensed from a 10-milliliter semimicro buret. The second component, designated as B, was dispensed from a 5-nri.Hiliter semimicro buret which was equipped with a reserve reservoir and was self-filling. The alcohol, when either methanol or isopropanol was used, was dispensed from a calibrated 50-raiHiliter Exax blue- line buret. When the third component of the system was absolute ethanol, a special all Pyrex glass dispensing device was needed to prevent the absorption of water by the alcohol. A diagram of this apparatus is shown in Figure 1. The buret, A, was a cali­ brated 50-milliliter Pyrex buret equipped with a three-way stop­ cock, B. A 10/50 standard taper joint, C, was sealed onto the stopcock. C 1 is also a 10/30 standard taper joint. The reserve reservoir, D, for the ethanol was a one liter round bottom flask equipped with two 2k/1fO standard taper necks. One of these con­ tained a plug, E, which could be removed for refilling of the reservoir. The other neck contained F, an air inlet that was guarded by a drying tube, G, filled with 10-20 mesh Drierite to remove moisture from the incoming air. The buret itself was also protected from moisture with a drying tube, G 1, filled with

Drierite.

Chemicals

Alcohol.— The alcohols used were obtained commercially.

The methanol was anhydrous, acetone free, Analytical Reagent

Grade from Mallinckrodt Chemical Works. The ethanol was United

States Pharmacopeia grade ethanol obtained from Commercial FIGURE 1 General schematic of the all Pyrex dispensing apparatus used in measuring and transferring absolute ethanol to the titration cell.

20 \

Vr/ U-S'G 22

Solvents Corporation. The isopropanol was the 99 per cent grade

obtained from Sohio. These alcohols were used without further purification and the only alcohol which required special handling was absolute ethanol which was dispensed by means of the apparatus previously described in Figure 1,

Aromatic hydrocarbons.— The benzene used was Analytical

Reagent Grade (thiophene Free) obtained from Mallinckrodt

Chemical Works. The toluene and xylene were both Analyzed Re­

agent Grade from Baker Chemical Company. The mesitylene and p-cymene were obtained from Eastman Kodak Company, the p-cymene , being of Practical Grade. Each of these hydrocarbons were used as received \tfithout further purification.

Aliphatic hydrocarbons.— All of the aliphatic hydrocarbons used were obtained from the "bank" of the Ohio State University

Hydrocarbon Research Laboratory through the courtesy of Dr. Ken­ neth W. Greenlee. Indices of refraction at 20°C. were taken for

each sample. These results are shown in Table III. Each of

these hydrocarbons were either proved to be or believed by

Dr. Greenlee and his staff to be at least 99 per cent pure with

the single exception of 2,3 dimethylpentane which was technical grade and known to be more than 95 per cent pure. As will be seen in Table III the indices of refraction were found to be

quite close to the theoretical values. As a further check on the purity of these samples, peroxide numbers were run on them. In

this procedure a one-milliliter sample of the hydrocarbon was reacted with potassium iodide in a solution which contained equal 23

TABLE III COMPARISON OF EXPERIMENTAL INDICES OF REFRACTION TO THEORETICAL VALUES

Theoretical Index Experimental Index Compound of Refraction of Refraction n-hexane 1.37486 1.3749 n-heptane 1.38764 1.3876 n-octane 1.39743 1.3974 n-decane 1.41189 1.4120 n-dodecane 1.42176 1.4217 n-tetradecane 1.42892 1.4290 2 methylpentane 1.37145 1.3715 3 methylpentane 1.37652 1.3767 3 methylhexane 1.38864 1.3887 3 methylheptane 1.39848 1.3986 2,2 dimethylbtitane 1.36876 1.3689 2,3 dimethylbutane 1.37495 1.3750 2,3 dimethylpentane 1.39196 1.3913 2,2,3 trimethylbutane 1.38944 1.3893 2,2,4 trimethylpentane 1.37495 1.3750

parts of acetic acid and acetone. This reaction was carried out

under a carbon dioxide atmosphere to prevent air oxidation. The

liberated iodine was then titrated with 0.01N sodium thiosulfate

solution to the disappearance of the iodine color. The number of

milliliters of sodium thiosulfate required for titration is equal

in value to the peroxide number for the sample. If the peroxide

number for the aliphatic hydrocarbon sample was greater than five,

the sample was passed one or more times through a column filled

with 28-200 mesh activated silica gel, Grade 12, obtained from

Davison Chemical Company. This passage effected the removal of any oxygenated compounds which were present in the sample. A

peroxide number was then taken on the sample and if it was not

five or less the purification was repeated. The samples were

then stored under a nitrogen atmosphere to prevent air oxidation until used.

Water for titrations.— The water used in all the titra­

tions was double distilled and was obtained from The Ohio State

University Laboratory Supply Stores Reagent Laboratory. This water contained less than one part per million of impurities

expressed in terms of sodium chloride. EXPERIMENTAL PROCEDURES

Aromatic hydrocarbon mixtures

All titrations were performed on a macro scale with a visual detection of the end point. The samples contained two aromatic hydrocarbons dissolved in an aliphatic alcohol and were titrated with water at 25°C. until turbidity appeared. The following mixtures were prepared:

Hydrocarbon A Hydrocarbon B Solvent

mesitylene benzene ethanol p-cymene benzene ethanol xylene benzene ethanol mesitylene toluene ethanol p-cymene toluene ethanol mesitylene benzene isopropanol p-cymene benzene isopropanol xylene benzene isopropanol mesitylene toluene isopropanol p-cymene toluene isopropanol mesitylene benzene methanol p-cymene benzene methanol xylene benzene methanol mesitylene toluene methanol p-cymene toluene methanol

Enough solid iodine to give a yellow to brown color was added to each mixture prior to titration in order to give a greater contrast at the end point. The amount of iodine was

25 26 found not to be critical since it undergoes no chemical reaction with any of the components of the system.

For hydrocarbon mixtures dissolved in ethanol, standard curves were prepared from 1,00 ml., 2.00 ml,, 3»00 ml., 5*00 ml., and 6.00 ml. total hydrocarbon volumes. Each of the binary hydrocarbon mixtures were diluted to 40.00 ml. with ethanol, solid iodine was added, and they were titrated with water to the appearance of turbidity at 25°C. Another set of standard curves were obtained by the addition of an additional 10.00 ml. of ethanol after the end point had been reached and a second titra­ tion with water to the appearance of turbidity.

For hydrocarbon mixtures dissolved in isopropanol, standard curves were prepared for 2.00 ml., 3.00 ml., 4.00 ml.,

5.00 ml., 6.00 ml., 7*00 ml., and 8.00 ml. total hydrocarbon volumes. These mixtures were also diluted to 40.00 ml. with isopropanol, titrated with water to the appearance of turbidity at 25°C., diluted with an additional 10.00 ml. isopropanol, and again titrated with water to the appearance of turbidity at 25°C.

For hydrocarbon mixtures dissolved in methanol, standard curves were prepared for l o00 ml., 2.00 ml., 3*00 ml., 4.00 ml.,

5.00 ml., and 6.00 ml. total hydrocarbon volumes. These mixtures were diluted to 50*00 ml. with methanol, titrated with water to the appearance of turbidity at 25°C., diluted with an additional

10.00 ml. methanol, and titrated with water again to the appear­ ance of turbidity at 25°C. 27

A standard curve for a given total hydrocarbon volume was determined by titration of accurately measured known samples.

These samples were prepared by measuring from calibrated serai- micro burets binary hydrocarbon mixtures that contained 100 per cent hydrocarbon A and 0 per cent hydrocarbon B, 75 per cent A and 25 per cent B, 50 per cent A and 50 per cent B, 25 per cent

A and 75 per cent B, and 0 per cent A and 100 per cent B. These mixtures were accurately diluted by the addition of enough ailcohol to bring the total volume to 4-0.00 ml. in the case of ethanol and isopropanol and 50.00 ml. in the case of methanol.

These dilutions were made neglecting any volume changes due to contraction or expansion upon dilution. A small amount of solid iodine was added, the titration cell put in place, and the titration was immediately begun. The dilution of the binary hydrocarbon mixture with alcohol resulted in an endothermic reaction. Previous investigations recommended allowing the solution to attain thermal equilibrium with the water bath.

This was found to be an unnecessary expenditure of time since the addition of water to the mixture always resulted in an exo­ thermic reaction. The only time the temperature of the solution needed to be exactly at 25°C. was when the titration was close to completion. Water was added rapidly with stirring to within a few milliliters of the expected end point. This resulted in an increase of temperature generally to around 50° to 55°C» £he solution was then allowed to reach thermal equilibrium with the water bath at 25°C. The titration was then completed by slow 28 addition of water while maintaining the temperature of the solution at 25°C. This method of titration was found to take much less time than the method of slow addition of water through­ out the titration. When titrating an unknown in which the ap­ proximate volume of water needed is not known, it is advisable to do a preliminary titration in which the end point is deter­ mined approximately. Another sample can then be taken and the end point approached in the manner explained above.

The end point was taken as that volume of water which resulted in a turbidity dense enough to just obscure the mercury

bulb of the thermometer which was inserted in the titration cell. When the total hydrocarbon content was 3»00 ml. or above when ethanol and methanol were used, or *t.00 ml. or above when isopropanol was used, the addition of one drop of water at the end point was generally sufficient to change the turbidity from a trace to complete obscuration of the thermometer. Only in the more dilute hydrocarbon range was there a need for a standard measure of turbidity. The volume of water in a titration re­ quired to obscure the thermometer completely was found to be quite reproducible and was much easier to detect than the point at which first permanent traces of turbidity appeared.

When the end point was reached, the stopper of the titra­ tion cell was lifted and 10.00 ml. of the appropriate alcohol was added accurately from a calibrated pipet. The stopper was replaced, the solution stirred, and a second titration was per­ formed in exactly the same manner as was the first. Aliphatic hydrocarbon mixtures

All titrations were performed on a macro scale with a

visual detection of the end point. The samples contained two

saturated aliphatic hydrocarbons dissolved in isopropanol and were titrated with water to the appearance of turbidity at 25°C.

Ethanol and methanol were also tested with the aliphatic mixtures but they were not found to give satisfactory titration volumes

and the end points were not as distinct as when isopropanol was

used. The following mixtures were prepared:

Hydrocarbon A Hydrocarbon B Total Volume A + B n-decane n-heptane 2.00 ml n-decane n-hexane 3.00 ml o o n-decane n-heptane * ml o o n-decane n-octane • ml n-dodecane n-decane 2.00 ml n-dodecane n-octane 3.00 ml n-tetradecane n-decane 2.00 ml o o n-tetradecane n-octane • ml n-decane 2 methylpentane 2.00 ml n-decane 2 ,2 ,^ trimethyl- 2.00 ml pentane o o n-decane 2 methylpentane • ml O o n-decane 2 ,2 ,^ trimethyl- . ml pentane o o n-decane 3 methylpentane . ml o o n-decane 2,3 dimethylpentane . ml -3" o o n-decane 2,3 dimethylbutane . ml K'* o o n-decane 2 ,2,3 trimethyl- . ml o o n-decane 3 methylhexane . ml o o n-decane 3 methylheptane . ml o o n-decane 2,2 dimethylbutane . ml 30 n-dodecane 3 methylpentane 3.00 ml n-dodecane 3 methylhexane 3.00 ml n-tetradecane 2 methylpentane 3.00 ml n-tetradecane 3 methylheptane 3.00 ml n-heptane 2,2,3 trimethyl- 3.00 ml butane o o n-heptane 2,3 dimethylpentane • ml o o 3 methylheptane 2 methylpentane • ml 3 methylheptane 2,3 dimethylpentane 3.00 ml 3 methylhexane 2 methylpentane 3.00 ml -r o o n-heptane 2,2 dimethylbutane . ml rA o o n-heptane n-hexane • ml n-octane 2,2,*f trimethyl- 3.00 ml pentane

Each of these mixtures was diluted to 50.00 ml. with isopropanol and titrated with water to the appearance of tur­ bidity at 25°C. The only difference between the titration of aliphatic hydrocarbon mixtures and that previously described for aromatic hydrocarbon mixtures was the method for end point de­ tection. The turbidity was not as intense with the aliphatic hydrocarbon mixtures as with aromatic hydrocarbon mixtures. The end point could not be taken as that volume of water required to give a turbidity which completely obscures the thermometer since the hydrocarbon rich layer would often separate and float to the surface before the turbidity becomes that intense. The end point of the titration was therefore taken as that volume of water which was required to produce a turbidity such that the lettering on the manufacturer's name plate on the water circulator directly behind the titration cell was no longer visible. This proved to be a reliable standard for the turbidity of the solution. EXPERIMENTAL DATA

The data obtained by the titration of binary hydrocarbon mixtures are listed in the form of tables and are represented

graphically in figures which summarize these data. Tables IV to

XIII, and Figures 2 to 11, show the results obtained for the

titration of the various binary aromatic hydrocarbon-ethanol mixtures. Tables XIV to XXIII and Figures 12 to 21 show the

results obtained for the titration of the various binary aromatic hydrocarbon-isopropanol mixtures. Tables XXIV to XXXIII and

Figures 22 to 31 show the results obtained for the titration of

the various binary aromatic hydrocarbon-methanol mixtures.

Tables XXXIV to LXI and Figures 32 to 39 show the results ob­

tained for the titration of the various binary aliphatic hydro­

carbon-isopropanol mixtures.

The volume of water required for the appearance of tur­

bidity that is listed in the tables is in each case an average

value of at least two titrations. Those volumes which correspond

to the titration of pure hydrocarbon A-alcohol mixtures and of

pure hydrocarbon B-alcohol mixtures are generally the average of

four or five titrations, since each time a new system was in­

vestigated the runs on the pure components-alcohol mixtures were

repeated even though duplicate values had been obtained pre­

viously for the same mixtures and at the same concentrations.

31 Tables XXV, XXVII, and XXIX, and Figures 12, 1^-, and 16 show no titration volume for 1,00 ml, of benzene when diluted to 60,00 ml, with methanol. This was because the concentration was too low for the appearance of turbidity. 33

TABLE IV TITRATION OF MESITYLENE-BENZENE-ETHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 40.00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) and Benzene (B) 100%A 7 5$ A 50%k 25%A 0%A Ml. 0%B 25#B 5CP/oB 75%B. 100%B

1.00 26.04 29.02 33.80 41.92 70.90 2.00 17.67 20.54 24.44 30.86 45.11 3.00 13.57 15.95 19.38 24.96 35.16 4.00 10.97 13.07 16.12 20.82 28.94 5.00 9.16 11.10 13.78 17.96 24.47 6.00 7.86 9.56 12.00 15.62 21.16

TABLE V TITRATION OF MESITYLENE-BENZENE-ETHANOL MIXTURES HAVING A 1TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) and Benzene (B) 100%A 75%A 50%A 25%A 0%A Ml. 0%B 25fbB 50%B 75%B lOO^B

1.00 36.44 40.44 46.85 57.48 117.00 2.00 25.21 28.94 34.14 42.93 64.89 3.00 ' 19.76 23.02 27.73 35.05 50.55 4.00 16.17 19.08 23.28 29.87 42.31 5.00 13.71 16.44 20.18 26.12 36.12 6.00 11.90 14.27 18.00 23.12 31.68 *

FIGURE 2 Titration curves of mesitylene-benzene-ethanol mixtures having a total dilution volume of ^0.00 ml.

Curve I - Mesitylene + benzene volume, 1.00 ml

Curve II - Mesitylene + benzene volume, 2.00 ml

Curve III - Mesitylene + benzene volume, 3.00 ml

Curve IV - Mesitylene + benzene volume, ^f.00 ml

Curve V - Mesitylene + benzene volume, 5.00 ml

Curve VI - Mesitylene + benzene volume, 6.00 ml 60

-©■ FIGURE 3 Titration curves of mesitylene-benzene-ethanol mixtures having'a total dilution volume of 50»00 ml.

Curve I - Mesitylene + benzene volume, 1.00 ml

Curve II - Mesitylene + benzene volume, 2.00 ml

Curve III - Mesitylene + benzene volume, 3.00 ml

Curve IV - Mesitylene + benzene volume, 4.00 ml

Curve V - Mesitylene + benzene volume, 5.00 ml

Curve VI - Mesitylene + benzene volume, 6.00 ml

36 Woter-ml. 40 120 20 50 70 30 60 80 110 25 Hydrocarbon B by - volume% 3ZE 0 75 50 100 38

TABLE VI TITRATION OF p-CYMENE-BENZENE-ETHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 40.00 ML.

Total Volume, Volume of Water Kequired, Ml. p-Cymene (A) and Benzene (B) 100>oA 75/&A 50%A 25%A 0%A Ml. 0%B 25/oB 50%B 75^B 100%B

1.00 24.66 27.9^ 32.52 40.34 70.90 2.00 17.10 19.76 23.40 29 .5^ 45.11 3.00 13.24 15.44 18.70 23.89 35.16 4.00 • 10.75 12.73 15.53 20.06 28.94 5.00 9.12 10.86 13.37 17.31 24.47 6.00 7.82 9.40 11.64 15.14 21.16

TABLE VII TITRATION OF p-CYMENE-BENZENE-ETHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML. \ Total Volume, Volume of Water Required, Ml. p-Cymene (A) and Benzene (B) 100&A 7 5/A 507oA 25% A 0%A ua. 0%B 25%B 50%B 75%'B 100/SB

1.00 3^.27 38.74 44.78 55.08 117.00 2.00 24.31 27.98 32.76 41.30 64.89 3.00 19.16 22.20 26.60 33.86 50.55 4.00 15.79 18.52 22.46 28.78 42.31 5.00 13.52 15.98 19.51 25.07 36.12 6.00 11.72 14.00 17.17 22.20 31.68 FIGURE 4 Titration curves of p-cymene-benzene-ethanol mixtures having a total dilution volume of 40.00 ml.

Curve I - p-cymene + benzene volume, 1.00 ml.

Curve II - p-cymene + benzene volume, 2.00 ml. r<\ o o Curve III - p-cymene + benzene volume, . ml. o O Curve IV - p-cymene + benzene volume, . ml.

Curve V - p-cymene + benzene volume, 5.oo ml.

Curve VI - p-cymene + benzene volume, 6.00 ml.

39 E40 Water I 50 - 60 70 30 20

0 25 ocr - % b volume by % - B n o carb ro d y H 50 75 100 ko FIGURE 5 Titration curves of p-cymene-benzene-ethanol mixtures having a total dilution volume of 50.00 ml.

Curve I - p-cymene + benzene volume, 1.00 ml.

Curve II - p-cymene + benzene volume, 2.00 ml.

Curve III - p-cymene + benzene volume, 5.00 ml.

Curve IV - p-cymene + benzene volume, ^.00 ml.

Curve V - p-cymene + benzene volume, 5.00 ml.

Curve VI - p-cymene + benzene volume, 6.00 ml. Water - ml. 120 110 70 40 60 80 20 30 0 p— 25 yrcro B y volume by % - B Hydrocarbon 50 nr 5 7 100 k 2 43

TABLE VIII TITRATION OF XYLENE-BENZENE-ETHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 40.00 ML.

Total Volume, Volume 'of Water Required, Ml. Xylene (A) and Benzene (B) 100%A 75%k 50^A 25%A 0%A Ml. 0%B 25%B 50%B 75%B 100%B

1.00 37.04 40.24 45.38 52.66 70.90 2.00 25.69 28.32 32.00 36.90 45.11 3.00 20.09 22.38 25.24 29.27 35.16 4.00 16.34 18.40 21.10 24.38 28.94 5.00 13.81 15.69 17.85 20.81 24.47 6.00 11.90 13.47 15.50 18.02 21.16

TABLE IX TITRATION OF XYLENE-BENZENE-ETHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. Xylene (A) and Benzene (B) 100%A 7 5% A 50?6A 25%A 0%A Ml. 0%B 25%B 50%B 7 % B 100/3B

1.00 51.46 55.89 62.96 74.15 117.00 2.00 36.22 40.06 45.24 52.07 64.89 3.00 28.86 32.20 36.21 41.83 50.55 4.00 24.01 26.80 30.44 35.22 42.31 5.00 20.49 23.18 26.22 30.50 36.12 6.00 17.89 20.16 23.08 26.84 31.68 FIGURE 6 Titration curves of xylene-benzene-ethanol mixtures having a total dilution volume of 4-0.00 ml.

Curve I - Xylene + benzene volume, 1.00 ml.

Curve II - Xylene + benzene volume, 2.00 ml.

Curve III - Xylene + benzene volume, 5.00 ml.

Curve IV - Xylene + benzene volume, 4.00 ml.

Curve V - Xylene + benzene volume, 5.00 ml.

Curve VI - Xylene + benzene volume, 6.00 ml.

44 «0

~0~

IOo FIGURE 7 Titration curves of xylene-benzene-ethanol mixtures having a total dilution volume of 50.00 ml.

Curve I - Xylene + benzene volume, 1.00 ml.

Curve II - Xylene + benzene volume, 2.00 ml.

Curve III - Xylene + benzene volume, 3.00 ml.

Curve IV - Xylene + benzene volume, 4.00 m l .

Curve V - Xylene + benzene volume, 5.00 ml.

Curve VI - Xylene + benzene volume, 6.00 ml.

46 Water - ml. 100 120 20 40 30 90 110 80 50 60 70 25 yrcro B- % b volume by % B - Hydrocarbon 321 50 10075 48

TABLE X TITRATION OF MESITYLENE-TOLUENE-ETHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 40.00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) and Toluene (B) 1 0 0 % A 75%A 50% A 25%A Qf%k Ml. 0$B 25%B 50%B 75#B 100%B

1.00 26.04 28.51 32.34 37.98 47.97 2.00 17.67 20.02 22.72 26.94 33.51 3.00 13.57 15.42 17.92 21.21 26.34 4.00 10.97 12.65 14.75 17.64 21.64 5.00 9.16 10.61 12.46 14.94 18.41 6.00 7.86 9.10 10.76 12.92 15.88

TABLE XI TITRATION OF MESITYLENE-TOLUENE-ETHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50 .00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) and Toluene (B) 100%A 75%A 50°/oA 2 5%A Qf%k Ml. 0%B 25%B 5C $ B 75%B 100%B

1.00 36.44 39.69 44.80 52.51 67.42 2.00 25.21 28.32 32.23 37.98 47.42 3.00 19.76 22.24 25.78 30.44 37.86 4.00 16.17 18.52 21.54 25.64 31.63 5.00 13.71 15.77 18.42 22.06 27.15 6.00 11.90 13.69 16.10 19.27 23.70 FIGURE 8 Titration curves of mesitylene-toluene-ethanol mixtures having a total dilution volume of *+0.00 ml.

Curve I - Mesitylene + toluene volume, 1.00 ml

Curve II - Mesitylene + toluene volume, 2.00 ml

Curve III - Mesitylene + toluene volume, 3.00 ml

Curve IV - Mesitylene + toluene volume, *+.00 ml

Curve V - Mesitylene + toluene volume, 5.00 ml

Curve VI - Mesitylene + toluene volume, 6.00 ml

*+9

FIGURE 9 Titration curves of mesitylene-toluene-ethanol mixtures having a total dilution volume of 50.00 ml.

Curve I - Mesitylene + toluene volume, 1.00 ml.

Curve II - Mesitylene + toluene volume, 2.00 ml.

Curve III - Mesitylene + toluene volume, 3.00 ml.

Curve IV - Mesitylene + toluene volume, ^.00 ml.

Curve V - Mesitylene + toluene volume, 5.00 ml.

Curve VI - Mesitylene + toluene volume, 6.00 ml.

51 e- by V0IU 53

TABLE XII TITRATION OF p-CYMENE-TOLUENE-ETHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 40.00 ML.

Total Volume, Volume of Water Required, Ml. p-Cyraene (A) and Toluene (B) 100% A 75%A 50%A 2 5% A 0%A Ml. 0%B 25%B 50%B 75%B 100%B

1.00 24.66 27.23 30.77 36.44 47.97 2.00 17.10 19.20 21.99 26.19 33.51 3.00 13.24 15.02 17.38 20.80 26.34 4.00 10.75 12.24 14.2.6 17.16 21.64 5.00 9.12 10.40 12.23 14.69 1 8 .4l 6.00 7.82 9.03 10.56 12.76 15.88

TABLE XIII TITRATION OF p-CYKEHE-TCLUENE-ETHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. p-Cymene (A) and Toluene (B) 100%A 75%A 50%A 2 5% A 0%A Ml. 0%B 25%B 50%B 75%B 100%B

1.00 34.27 37.80 42.64 50.25 67.42 2.00 24.31 27.12 30.88 36.66 47.42 3.00 19.16 21.58 24.82 29.63 37.86 4.00 15.79 17.90 20.67 24.82 31.63 5.00 13.52 15.36 17.93 21.55 27.15 6.00 11.72 13.46 15.74 18.92 23.70 FIGURE 10 Titration curves of p-cymene-toluene-ethanol mixtures having a total dilution -volume of *f0,00 ml.

Curve I - p-cymene + toluene volume, 1.00 ml.

Curve II - p-cymene + toluene volume, 2.00 ml.

Curve III - p-cymene + toluene volume, 3.00 ml. -4- o o

Curve IV - p-cymene + toluene volume, • ml.

Curve V - p-cymene + toluene volume, 5.00 ml.

Curve VI - p-cymene + toluene volume, 6.00 ml.

5^ Hbfer- 'roc°rbon FIGURE 11 Titration curves of p-cymene-toluene-ethanol mixtures having a total dilution volume of 50.00 ml.

Curve I - p-cymene + toluene volume, 1.00 ml.

Curve II - p-cymene + toluene volume, 2.00 ml.

Curve III - p-cymene + toluene volume, 3.00 ml.

Curve IV - p-cymene + toluene volume, if.00 ml. \ Curve V - p-cymene +' toluene volume, 5.00 ml.

Curve VI - p-cymene + toluene volume, 6.00 ml.

56 by v°tum 58

TABLE XIV TITRATION OF MESITYLENE-BENZENE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 40.00 ML.

Total Volume, Volume of Water Required, Ml, Mesitylene (A) and Benzene (B) 100% A 7 5%A 50%A 25%A CP/ok Ml. 0%B 25%B 50%B 75%B 100%B

2.00 35.53 40.06 46.2*4 54.82 68.26 3.00 27.93 32.25 38.04 45.47 54.65 4.00 22.89 27.08 32.40 38.78 45.36 5.00 19.49 23.21 28.12 33.48 38.38 6.00 16.77 20.21 24.78 29.25 32.73 7.00 14.53 17. ?4 21.80 25.58 28.23 8.00 12.95 15.85 19.58 22.55 24.00

TABLE XV TITRATION OF MESITYLENE-BENZENE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) ; and Benzene (B) 100%A 75%A 50%A 25%A CP/ok Ml. 0%B 25%B 50%B 75%B 100%B

2.00 49.67 55.60 63.64 75.19 96.81 3.00 39.99 45.62 53.28 63.54 78.38 4.00 33.35 38.90 45.89 54.97 66.04 5.00 28.80 33.88 40.58 48.49 56.76 6.00 25.10 29.84 36.21 43.16 49.47 7.00 22.15 26.58 32.35 38.56 43.77 8.00 19.89 24.06 29.43 34.80 38.62 I

FIGURE 12 Titration curves of mesitylene-benzene-isopropanol mixtures having a total dilution of 40.00 ml.

Curve I - Mesitylene + benzene volume, 2.00 ml.

Curve II - Mesitylene + benzene volume, 3.00 ml.

Curve III - Mesitylene + benzene volume, 4.00 ml.

Curve IV - Mesitylene + benzene volume, 5.00 ml.

Curve V - Mesitylene + benzene volume, 6.00 ml.

Curve VI - Mesitylene + benzene volume, 7.00 ml.

Curve VII - Mesitylene + benzene volume, 8.ooml.

59 Water - ml. 20 30 60 40 50 70 25 yrcro B—% y volume by —% B Hydrocarbon 3zn 50 HI m 75 100 60 FIGURE 13 Titration curves of mesitylene-benzene-isopropanol mixtures having a total dilution volume of 30.00 ml.

Curve I - Kesitylene + benzene volume, 2.00 ml.

Curve II - Kesitylene + benzene volume, 3.00 ml.

Curve III - Kesitylene + benzene volume, *l-.00 ml. I Curve IV - Mesitylene + benzene volume, 5.00 ml.

Curve V - Mesitylene + benzene volume, 6.00 ml.

Curve VI - Mesitylene + benzene volume, 7.00 ml.

Curve VII - Kesitylene + benzene volume, 8.00 ml.

61 Water - ml. 100 90 60 80 20 30 40 70 50 5 2 0 yrcro B- y volume by % - B Hydrocarbon w EC HE 50 5 7 0 0 1 62 63

TABLE XVI TITRATION OF p-CYMENE-BENZENE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 4 0 . 0 0 ML.

Total Volume, Volume of Water Required, Ml. p-Cymene (A) and Benzene (B) 100%A 75°/oA 50%A 25%A 0%A Ml. 0%B 25%B 50%B 75%B 100%B

2.00 33.12 37.66 43-54 52.47 68.26 3.00 26.35 30.38 35.98 43.64 54.65 4.00 21.71 25.44 30.39 37.36 45.36 5.00 18.50 21.85 25.54 32.53 38.38 6.00 16.05 19.15 23.34 28.44 32.27 7.00 14.01 16.88 20.75 25.03 2S.23 8.00 12.44 15.08 18.55 22.08 24.00

TABLE XVII TITRATION OF p-CYMENE-BENZENE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. p-Cymene (A) and Benzene (B) 100% A 75% A 50%A 2 5%A 0%A Ml. 0%B 25%B 50%B 75%B 1 0 0 % B

2.00 46.39 52.37 59.86 71.76 96.81 3.00 37.62 43.05 50.38 60.22 78.38 4.00 31.59 36.56 43.27 52.86 66.04 5.00 27.24 31.86 38.26 46.91 56.76 6.00 23.91 28.26 34.12 41.79 49.47 7.00 21.16 25.24 30.74 37.49 43.77 8.00 19.02 22.78 27.81 33.83 38.62 FIGURE l4 Titration curves of p-cymene-benzene-isopropanol mixtures having a total dilution volume of 40.00 ml.

Curve I - p-cymene + benzene volume, 2.00 ml.

Curve II - p-cymene + benzene volume, 3.00 ml.

Curve III - p-cymene + benzene volume, 4.00 ml.

Curve IV - p-cymene + benzene volume, 5.00 ml.

Curve V - p-cymene + benzene volume, 6.00 ml.

Curve VI - p-cymene + benzene volume, 7.00 ml.

Curve VII - p-cymene + benzene volume, 8.00 ml.

64 Water - ml. 20 40 30 50 70 5 2 yrcro B b volume by —% B Hydrocarbon m m 50 5 7 1000 65 FIGURE 15 Titration curves of p-cymene-benzene-isopropanol mixtures having a total dilution volume of 50*00 ml.

Curve I - p-cymene + benzene volume, 2.00 ml.

Curve II - p-cymene + benzene volume, 5.00 ml.

Curve III - p-cymene + benzene volume, ^f.00 ml.

Curve IV - p-cymene + benzene volume, 5.00 ml.

Curve V - p-cymene + benzene volume, 6.00 ml.

Curve VI - p-cymene + benzene volume, 7.00 ml.

Curve VII - p-cymene + benzene volume, 8.00 ml.

66 Water - ml. 20 100 30 40 50 60 90 70 80 25 doabn — y volume by % B— ydrocarbon H w 3ZT 50 75 100 67 68

TABLE XVIII TITRATION OF XYLENE-BENZENE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 40.00 ML.

Total Volume, Volume of Water Required, Ml. Xylene (A) and Benzene (B) 100%A 7 5% A 50%A 25%A 0%A Ml. OP/oB 25%B 50%B 75%B 100%B

2.00 45.57 49.30 54.06 59.99 68.26 3.00 36.94 40.35 if if. 32 if 8.72 5^.65 00 30.88 34.14 37.61 ifl.30 45.36 5.00 26.50 29.44 32. if 2 35.34 38.38 6.00 23.05 25.62 28.23 30.52 32.73 7.00 20.26 22.56 2if .70 26.60 28.23 8.00 17.96 19.98 21.72 23.02 2if.OO

TABLE XIX TITRATION OF XYLENE-BENZENE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. Xylene (A) and Benzene (B) 100%A 7 5% A 5d/bA 25%A 0%A Ml. Cf/cB 25%B 507oB 75%B 100%B

2.00 63.44 68.12 74.78 83.09 96.81 3.00 52.30 56.72 62.28 68.82 78.38 if.00 if if. if l 48.81 53.75 59.21 66.04 5.00 38.74 42.78 47.12 51.63 56.76 6.00 34.18 37.82 41.74 45.52 49.47 7.00 30. if 4 33.84 37.32 40.64 43.77 8.00 27.35 30.38 33.46 36.11 38.62 FIGURE 16 Titration curves of xylene-benzene-isopropanol mixtures having a total dilution volume of 40.00 ml.

Curve I - Xylene + benzene volume, 2.00 ml.

Curve II - Xylene + benzene volume, 3.00 ml.

Curve III - Xylene + benzene volume, 4.00 ml.

Curve IV - Xylene + benzene volume, 5.00 ml.

Curve V - Xylene + benzene volume, 6.00 ml.

Curve VI - Xylene + benzene volume, 7.00 ml.

Curve VII - Xylene + benzene volume, 8.00 ml.

69 ~o~ FIGURE 17 Titration curves of xylene-benzene-isopropanol mixtures having a total dilution volume of 50.00 ml.

Curve I - Xylene + benzene volume, 2.00 ml.

Curve II - Xylene + benzene volume, 5.00 ml.

Curve III - Xylene + benzene volume, k . 0 0 ml.

Curve IV - Xylene + benzene volume, 5.00 ml.

Curve V - Xylene + benzene volume, 6.00 ml.

Curve VI - Xylene + benzene volume, 7.00 ml.

Curve VII - Xylene + benzene volume, 8.00 ml.

71 foo

■ & -

-o_ 73

TABLE XX TITRATION OF MESITYLENE-TOLUENE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 40.00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) and Toluene (B) lOQP/oA 7 5% A 50%A 25%A Qffok Ml. CFjoB 25%B 50%B 75%B 100%B

2.00 35.53 38.79 43.30 48.32 55.09 3.00 27.93 31.25 35.06 39.66 44.78 4.00 22.89 25.94 29.45 33.48 37.74 5.00 19.49 22.11 25.26 28.86 32.22 6.00 16.77 19.14 22.08 25.22 28.01 7.00 14.53 16.78 19.40 22.20 24.57 8.00 12.95 14.90 17.26 19.77 21.48

TABLE XXI TITRATION OF MESITYLENE-TOLUENE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) and Toluene (B) 100%A 75%A 50%A 25%A 0%A Ml. 0%B 25%B 50%B 75%b 100%B

2.00 49.67 54.12 59.82 67.02 76.79 3.00 39.99 44.45 49.43 55*66 63.37 4.00 33.35 37.46 42.30 47.84 54.16 5.00 28.80 32.44 36.85 41.94 47.04 6.00 25.10 28.44 32.54 37.20 41.67 7.00 22.15 25.28 29.04 33.26 37.16 8.00 19.89 22.77 26.19 30.04 33.21 FIGURE 18 Titration curves of mesitylene-toluene-isopropanol mixtures having a total dilution volume of 40.00 ml.

Curve I - Mesitylene + toluene volume, 2.00 ml.

Curve II - Mesitylene + toluene volume, 3.00 ml.

Curve III - Mesitylene + toluene volume, 4.00 ml.

Curve IV - Mesitylene + toluene volume, 5.00 ml.

Curve V - Mesitylene + toluene volume, 6.00 ml.

Curve VI - Mesitylene + toluene volume, 7.00 ml.

Curve VII - Mesitylene + toluene volume, 8.00 ml.

7k Water - ml. 60 20 40 50 30 0 25 Hydrocarbon B % by - volume zm 3ZE m 50 75 0 0 1 FIGURE 19 Titration curves of mesitylene-toluene-isopropanol mixtures having a total dilution volume of 50.00 ml.

Curve I - Mesitylene + toluene volume, 2.00 ml.

Curve II - Mesitylene + toluene volume, 3.00 ml.

Curve III - Mesitylene + toluene volume, A-.00 ml.

Curve IV - Mesitylene + toluene volume, 5.00 ml.

Curve V - Mesitylene + toluene volume, 6.00 ml.

Curve VI - Mesitylene + toluene volume, 7.00 ml.

Curve VII - Mesitylene + toluene volume, 8.00 ml.

76 Water - ml. 20 30 0 8 40 60 70 50 25 yrcro B- % y volume by % B - Hydrocarbon 50 HI 75 100 77 78

TABLE XXII TITRATION OF p-CYMENE-TOLUENE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF *+0.00 ML.

Total Volume, Volume of Water Required, Ml. p-Cymene (A) and Toluene (B) 100%A 75%A 50%A 25%A 0%A Ml. 0%B 25%B 50%B 75%B 100%B

2.00 33.12 36.71 *+1.18 *+6.9*+ 55.09 3.00 26.35 29.57 33. *+6 38.53 *+*+.78 *+.00 21.71 2*+. 66 28.22 32.68 37.7*+ 5.00 18.50 21.19 2*+.28 28.26 32.22 6.00 16.05 1 8 . *+0 21.35 2*+. 80 28.01 7.00 1*+.01 16.16 18.82 21.8*+ 2*+.57 8.00 12.*+*+ 1*+.*+*+ 16.77 19.*+5 21. *+8

TABLE XXIII TITRATION OF p-CYMENE-TOLUENE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. p-Cymene (A) and Toluene (B) 100%A 75%A 50%A 25%A 0%A Ml. 0%B 25%B 50%B 75%B 100%B

2.00 *+6.39 51 .0*+ 56.97 6*+. 68 76.79 3.00 37.62 *+2.01 *+7.12 53.98 63.37 *+.00 31.59 35.51 *+0.*+8 *+6.6*+ 5*+.16 5.00 27 .2*+ 30.9*+ 35.23 *+0.9*+ *+7.0*+ 6.00 23.91 27.28 31.39 36 .*+6 *+1.67 7.00 21.16 2*+. 26 28 .0*+ 32.60 37.16 8.00 19.02 21.91 25.39 29.*+6 33.21 FIGURE 20 Titration curves of p-cymene-toluene-isopropanol mixtures having a total dilution volume of ifO.OO ml.

Curve I - p-cymene + toluene volume, 2.00 ml.

Curve II - p-cymene + toluene volume, 3.00 ml.

Curve III - p-cymene + toluene volume, if.00 ml.

Curve IV - p-cymene + toluene volume, 5.00 ml.

Curve V - p-cymene + toluene volume, 6.00 ml.

Curve VI - p-cymene + toluene volume, 7.00 ml.

Curve VII - p-cymene + toluene volume, 3.00 ml.

79 E Water I 40 20 30 50 60 0 25 Hydrocarbon % Bby volume - 3ZEL 50 75 100 80 i

FIGURE 21 Titration curves of p-cymene-toluene-isopropanol mixtures having a total dilution volume of 50.00 ml.

Curve I - p-cymene + toluene volume, 2.00 ml.

Curve II - p-cymene + toluene volume, 5.00 ml.

Curve III - p-cymene + toluene volume, *f.00 ml.

Curve IV - p-cymene + toluene volume, 5.00 ml.

Curve V - p-cymene + toluene volume, 6.00 ml.

Curve VI - p-cymene + toluene volume, 7.00 ml.

Curve VII - p-cymene + toluene volume, 8.00 ml.

81 Woter - ml. I- 0 2 30 40 50 60 80 - | > 25 doabn - % b vlme volum by % - B ydrocarbon H H Z 3 50 75 100 82 83

TABLE XXIV TITRATION OF MESITYLENE-BENZENE-METHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) and Benzene (B) 10096A 75% A 50%A 25%A 0%A ML. 0%B 2596b 50%B 7596b 10096b

1.00 17.73 20.78 24.60 32.50 76.60 2.00 11.79 14.14 17.16 22.62 41.03 3.00 8.93 10.91 13.48 18.10 30.2? 4.00 7.24 8.86 11.19 15.06 24.43 5.00 5.94 7.40 9.46 13.00 20.40 6.00 4.99 6.24 8.20 11.20 17.58

TABLE XXV TITRATION OF MESITYLENE-BENZENE-METHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 60.00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) and Benzene (B) 10096A 7 5% A 5096a 2596a 096a Ml. 096b 2596B 5096B 7596b 10096b

1.00 23.79 27.80 32.72 43.17 — 2.00 15.97 18.98 22.71 30.16 58.04 3.00 12.32 l4.8o 18.22 24.07 42.30 4.00 10.05 12.10 15.14 20.36 33.89 5.00 8.40 10.27 12.98 17.64 28.42 6.00 7.13 8.74 11.38 15.36 24.64 FIGURE 22 Titration curves of mesitylene-benzene-methanol mixtures having a total dilution volume of 50»00 ml.

Curve I - Mesitylene + benzene volume, 1.00 ml.

Curve II - Mesitylene + benzene volume, 2.00 ml.

Curve III - Mesitylene + benzene volume, 3.00 ml.

Curve IV - Mesitylene + benzene volume, *+.00 ml.

Curve V - Mesitylene + benzene volume, 5.00 ml.

Curve VI - Mesitylene + benzene volume, 6.00 ml.

8 * t 8 0

TO

60

50

30

20

2 5 50 75 100 Hydrocarbon B - % by volume FIGURE 23 Titration curves of mesitylene-benzene-methanol mixtures having a total dilution volume of 60.00 ml.

Curve I - Mesitylene + benzene volume, 1.00 ml

Curve II - Mesitylene + benzene volume, 2.00 ml

Curve III - Mesitylene + benzene volume, 3.00 ml

Curve IV - Mesitylene + benzene volume, 4.00 ml

Curve V - Mesitylene + benzene volume, 5.00 ml

Curve VI - Mesitylene + benzene volume, 6.00 ml

86 Water - ml. 60 80 50 70 20 40 30 0 5 2 yrcro B y volume by % - B Hydrocarbon 50 5 7 100 88

TABLE XXVI TITRATION OF p-CYMENE-BENZENE-METHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML. ; Total Volume, Volume of Water Required, Ml. p-Cymene (A) and Benzene (B) 100%A 7 5%A 5C$A 2 % k 0 % k Ml. 0$3 25%B 50^B 75%B lOCP/oB

1.00 17.76 20.16 23.66 30.9^ 76.60 2.00 11.88 13.74 16.64 21.76 41.03 3.00 8.95 10.64 13.03 17.34 30.27 4.00 7.25 8.73 10.86 14.53 24.43 5.00 6.03 7.37 9.31 12.52 20.40 6.00 5.09 6.30 8.l4 10.98 17.58

TABLE XXVII TITRATION OF p-CYMENE-BENZENE-METHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 60.00 ML.

Total Volume, Volume of 1in/ater Required, Ml. p-Cymene (A) and Benzene (B) lOO^A 7 5% A 5<$A 25%A QP/ok Ml. QP/oB 25%B 50#B 75%B 1 0 0 % B

1.00 23.38 26.60 31.22 40.83 — 2.00 15.9^ 18.52 22.18 28.87 58.04 3.00 12.27 14.40 17.55 23.21 42.30 4.00 10.01 11.96 14.68 19.53 33.89 5.00 8.4o 10.15 12.70 17.02 28.42 6.00 7.22 8 *8o 11.16 14.98 24.64 FIGURE 24 Titration curves of p-cymene-benzene-methanol mixtures having a total dilution volume of 50.00 ml.

Curve I - p-cymene + benzene volume, 1.00 ml.

Curve II - p-cymene + benzene volume, 2.00 ml.

Curve III - p-cymene + benzene volume, 3.00 ml.

Curve IV - p-cymene + benzene volume, 4.00 ml.

Curve V - p-cymene + benzene volume, 5.00 ml.

Curve VI - p-cymene + benzene volume, 6.00 ml.

89 40

-o- FIGURE 25 Titration curves of p-cymene-benzene-methanol mixtures having a total dilution volume of 60.00 ml.

Curve I - p-cymene + benzene volume, 1.00 ml.

Curve II - p-cymene + benzene volume, 2.00 ml.

Curve III - p-cymene + benzene volume, 3.00 ml.

Curve IV - p-cymene + benzene volume, If.00 ml.

Curve V - p-cymene + benzene volume, 5.00 ml.

Curve VI - p-cymene + benzene volume, 6.00 ml.

91 0cOrbOn 93

TABLE XXVIII TITRATION OF XYLENE-BENZENE-METHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. Xylene (A) and Benzene (B) 10096A 7596a 50%A 2596A

Ml. 0%B 23%B 50%B 7596b If

1.00 29.58 33.07 38.44 47.01 76.60 2.00 19.61 21.88 25.31 30.46 41.03 3.00 14.86 16.86 19.54 23.48 30.27 4.00 12.02 13.68 15.96 19.18 24.43 5.00 10.04 11.54 13.48 16.26 20.40 6.00 8.63 9.89 11.64 14.06 17.58

TABLE XXIX TITRATION OF XYLENE-BENZENE-METHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 60.00 ML.

Total Volume, Volume of Water Required, Ml. Xylene (A) and Benzene (B) IOO96A 7596A 5096A 2596A 096A Ml. 096B 2596B 5096B 7596b 10096b

1.00 39.84 44.44 51.68 65.08 — 2.00 26.46 29.44 33.97 41.30 58.04 3.00 20.15 22.90 26.50 31.96 42.30 4.00 16.50 18.86 21.78 26.35 33.89 5.00 13.98 15.98 18.67 22.45 28.42 6.00 12.06 13.78 16.15 19.49 24.64 FIGURE 26 Titration curves of xylene-benzene-methanol mixtures having a total dilution volume of 50.00 ml.

Curve I - Xylene + benzene volume, 1.00 ml.

Curve II - Xylene + benzene volume, 2.00 ml.

Curve III - Xylene + benzene volume, 3.00 ml.

Curve IV - Xylene + benzene volume, 4.00 ml.

Curve V - Xylene + benzene volume, 5.00 ml.

Curve VI - Xylene + benzene volume, 6.oo ml.

94 Woter - ml. 20 40 30 0 8 50 60 TO yrcro B y volume by % - B Hydrocarbon 50 m 100 FIGURE 27 Titration curves of xylene-benzene-methanol mixtures having a total dilution volume of 60.00 ml.

Curve I - Xylene + benzene volume, 1.00 ml.

Curve II - Xylene + benzene volume, 2.00 ml.

Curve III - Xylene + benzene volume, 3.00 ml.

Curve IV - Xylene + benzene volume, *f.00 ml.

Curve V - Xylene + benzene volume, 5.00 ml.

Curve VI - Xylene + benzene volume, 6.00 ml.

96 97 8 0

70

60

50

E I * I 40

30

20

0 25 50 7 5 100 Hydrocarbon B - % by volume 98

TABLE XXX TITRATION OF MESITYLENE-TOLUENE-METHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) and Toluene (B) 100%A 7 5% A 50%A 25%A 0#A Ml. 0%B 25^B 50%B 75%B 100%B

1.00 17.75 19.67 22.98 28.60 45.38 2.00 11.79 15.^1 15.97 19.^7 27.38 5.00 8.95 10.28 12.22 15.26 20.88 4.00 7.24 8.44 10.16 12.64 16.97 5.00 5.9^ 7.06 8.58 10.75 14.25 6.00 4.99 6.00 7.40 9.28 12.27

TABLE XXXI TITRATION OF MESITYLENE-TOLUENE-METHANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 60.00 ML.

Total Volume, Volume of Water Required, Ml. Mesitylene (A) and Toluene (B) 100%A 75%A 5 0 % A 2 5 % A QP/oA Ml. QP/oB 25%B 50%B 75 % B 100%B

1.00 25.79 26.29 50.48 58.12 59.74 2.00 15.98 17.99 21.56 26.02 57.12 5.00 12.52 14.02 16.62 20.57 28.40 4.00 10.05 11.65 15.84 17.24 25.32 5.00 8.40 9.82 11.90 14.76 19.72 6.00 7.15 8.48 10.29 12.87 17.09 FIGURE 28 Titration curves of mesitylene-toluene-methanol mixtures having a total dilution volume of 50.00 ml.

Curve I - Mesitylene + toluene volume, 1.00 ml

Curve II - Mesitylene + toluene volume, 2.00 ml

Curve III - Mesitylene + toluene volume, 3.00 ml

Curve IV - Mesitylene + toluene volume, *t.00 ml

Curve V - Mesitylene + toluene volume, 5.00 ml

Curve VI - Mesitylene + toluene volume, 6.00 ml

99

FIGURE 29 Titration curves of mesitylene-toluene-methanol mixtures having a total dilution volume of 60.00 ml.

Curve I - Mesitylene + toluene volume, 1.00 ml

Curve II - Mesitylene + toluene volume, 2.00 ml

Curve III - Mesitylene + toluene volume, 3.00 ml

Curve IV - Mesitylene + toluene volume, 4.00 ml

Curve V - Mesitylene + toluene volume, 5.00 ml

Curve VI - Mesitylene + toluene volume, 6.00 ml

101

103

TABLE XXXII TITRATION OF p-CYMENE-TOLUENE-METRANOL MIXTURES HAVING A TOTAL DILUTION OF 50.00 ML.

Total Volume, Volume of Water Required, Ml. p-Cymene (A) and Toluene (B) 100%A 75%A 50P/oA 2 5 % A 0%A Ml. 0%B 25%B 50%B 75%B 100%B

1.00 17.76 19.95 23.02 27.92 43.38 2.00 11.88 13.44 15.76 19.44 27.38 3.00 8.95 10.36 12.22 15.21 20.88 4.00 7.25 8.45 10.05 12.39 16.97 5.00 6.04 7.02 8.42 10.54 14.25 6.00 5.09 6.00 7.32 9.12 12.27

TABLE XXXIII TITRATION OF p-CYMENE-TOLUENE-METHANOL MIXTURES HAVING A TOTAL DILUTION OF 60.00 ML.

Total Volume, Volume of Water Required, Ml. p-Cymene (A) and Toluene (B) 100%A 75%A 50%A 25%A 0%A Ml. 0%B 25%B 50%B 75%B 100%B

1.00 23.38 26.45 30.44 37.32 59.74 2.00 15.94 18.06 21.12 26.13 37.12 3.00 12.27 14.06 16.60 20.46 28.40 4.00 10.01 11.58 13.72 16.90 23.32 5.00 8.40 9.75 11.64 14.53 19.72 6.00 7.22 8.42 10.19 12.62 17.09 FIGURE 30 Titration curves of p-cymene-toluene-methanol mixtures having a total dilution volume of 50.00 ml.

Curve I - p-cymene + toluene volume, 1.00 ml.

Curve II - p-cymene + toluene volume, 2.00 ml.

Curve III - p-cymene + toluene volume, 3.00 ml.

Curve IV - p-cymene + toluene volume, 4.00 ml.

Curve V - p-cymene + toluene volume, 5.00 ml.

Curve VI - p-cymene + toluene volume, 6.00 ml.

104 105

%drocorb0i FIGURE 31 Titration curves of p-cymene-toluene-methanol mixtures having a total dilution volume of 60.00 ml.

Curve I - p-cymene + benzene volume, 1.00 ml.

Curve II - p-cymene + benzene volume, 2.00 ml. f Curve III - p-cymene + benzene volume, 3.00 ml.

Curve IV - p-cymene + benzene volume, if.00 ml.

Curve V - p-cymene + benzene volume, 5.00 ml.

Curve VI - p-cymene + benzene volume, 6.00 ml.

106 Water - m l. 40 30 50 60 20 25 doabn - y ou e volum by % - B ydrocarbon H 50 75 100 107 1 0 8

TABLE XXXIV TITRATION OF N-DECANE-N-HEPTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML. n-Decane n-Heptane Water Required Ml. Ml. Ml.

2.00 0.00 22.i k

1.50 0.50 2k .78

1.00 1.00 28.02

0.50 1.50 32.53

0.00 2.00 39.2*f

3.00 0.00 17.06

2.25 0.75 19.06

1.50 1.50 21.80

0.75 2.25 25.56

0.00 3.00 31.17 109

TABLE XXXV TITRATION OF N-DECANE-N-HEXAND-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML. n-Decane n-Hexane Water Required Ml. Ml. Ml.

3.00 0.00 17.06 2.25 0.75 19.67 1.50 1.50 23.46 0.75 2.25 29.17 0.00 3.00 39.97

TABLE XXXVI TITRATION OF N -DECANE-N-OCTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML. n-Decane n-Octane Water Required Ml. Ml. Ml.

3.00 0.00 17.06 2.25 0.75 18.53 1.50 1.50 20.22 0.75 2.25 22.44 0.00 3.00 25.32 FIGURE 32 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml.

Curve I - n-decane + n-heptane volume, 2.00 ml.

Curve II - n-decane + n-hexane volume, 5.00 ml.

Curve III - n-decane + n-heptane volume, 5.00 ml.

Curve IV - n-decane + n-octane volume, 3.00 ml.

110 Water - m l . 30 40 20 35 25 doabn % b vlme volum by % B - ydrocarbon H m E E 50 75 Ill 100 112

TABLE XXXVII TITRATION OF N-DECANE-2 METHYLPENTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Decane 2 Methylpentane Water Required Ml. Ml. Ml.

2.00 0.00 22.14 1.50 0.50 25.40 1.00 1.00 30.16 0.50 1.50 37.38 0.00 2.00 53.06 3.00 0.00 17.06 2.25 0.75 19.74 1.50 1.50 23.62 0.73 2.25 29.78 0.00 3.00 43.24

TABLE XXXVIII TITRATION OF N-DECANE-2,2,4 TRIMETHYLPENTANE -ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Decane 2,2,4 Trimethylpentane Water Required Ml. Ml. Id.

2.00 0.00 22.14 1.50 0.50 24.73 1.00 1.00 28.33 0.50 1.50 33.06 0.00 2.00 39.82 3.00 0.00 17.06 2.25 0.75 19.18 1.50 1.50 22.08 0.75 2.25 26.12 0.00 3.00 31.89 FIGURE 33 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50*00 ml.

Curve I - n-decane + 2 methylpentane volume, 2.00 ml.

Curve II - n-decane + 2,2,4 trimethylpentane volume, 2*00

Curve III - n-decane + 2 methylpentane volume, 3.00 ml.

Curve IV - n-decane + 2,2,4 trimethylpentane volume, 3*00

113 Water - ml. 20 40 30 50 0 25 yrcro B- % y volume by % B - Hydrocarbon 50 75 100 Ilk 115

TABLE XXXIX TITRATION OF N-DODECANE-N-DECANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML. n-Dodecane n-Decane Water Required Ml. Ml. Ml.

2.00 0.00 15.86 1.50 0.50 17.10 1.00 1.00 18.46 0.50 1.50 20.04 0.00 2.00 22.14

TABLE XL TITRATION OF N-DODECANE-N-OCTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML. n-Dodecane n-Octane Water Required Ml. Ml. Ml.

5.00 0.00 11.85 2.25 0.75 13.58 1.50 1.50 15.93 0.75 2.25 19.52 0.00 3.00 25.52 116

TABLE XLI TITRATION OF N-TETRADECANE-N-DECANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Tetradecane n-Decane Water Required Ml. Ml. Ml.

2.00 0.00 11.27 1.50 0.50 12.78 1.00 1.00 14.78 0.50 1.50 17.58 r\> o o 0.00 • 22.14

TABLE XLII TITRATION OF N- TETRADECANE-N-OCTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Tetradecane n-Octane Water Required Ml. Ml. Ml.

3.00 0.00 8.36 2.25 0.75 9.94 1.50 1.50 12.27 0.75 2.25 16.36 0.00 3.00 25.32 \

FIGURE 3*f Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50*00 ml.

Curve I - n-dodecane + n-decane volume, 2.00 ml.

Curve II - n-dodecane + n-octane volume, 3*00 ml.

Curve III - n-tetradecane + n-decane volume, 2.00 ml.

Curve IV - n-tetradecane + n-octane volume, 3*00 ml.

117

119 TABLE XLIII TITRATION OF N-DECANE-3 METHYLPENTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Decane 3 Methylpentane Water Required Ml. Ml. Ml.

3.00 0.00 17.06 2.25 0.75 19.82 1.50 1.50 23.89 0.75 2.25 30.42 0.00 3.00 42.83

TABLE XLIV TITRATION OF N-DECANE-2,3 DIMETHYLPENTANE-ISOPROPANOL MIXTURES HAVING A I3TAL DILUTION VOLUME OF 50.00 ML.

n-Decane 2,3 Dimethylpentane Water Required Ml. Ml. Ml.

3.00 0.00 17.06 2.25 0.75 19.44 1.50 1.50 22.87 0.75 2.25 27.88 0.00 3.00 36.30

TABLE XLV TITRATION OF N-DECANE-2,3 DIMETHYLBUTANE-ISOPROPANOL MIXTURES ]HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Decane 2,3 Dimethylbutane Water Required Ml. Ml. Ml.

4.00 0.00 13.84 3.00 1.00 16.32 2.00 2.00 20.02 1.00 3.00 26.04 0.00 4.00 38.10 FIGURE 35 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50*00 ml.

Curve I - n-decane + 3 methylpentane volume, 3*00 ml.

Curve II - n-decane + 2,3 dimethylpentane volume, 3*00 ml.

Curve III - n-decane + 2,3 dimethylbutane volume, 4.00 ml.

120 E Water i 40 20 30 35 25 0 25 yrcro B- % y volume by % B- Hydrocarbon 50 75 121 100 122

TABLE XLVI TITRATION OF N-DECANE-2,2,3 TEIMETHYLBUTANE-ISOPKOPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Decane 2,2,3 Trimethylbutane Water Required Ml. Ml. Ml.

5.00 0.00 17.06 2.25 0.75 19.62 1.50 1.50 23.^6 0.75 2.25 29.08 0.00 3.00 39.39

TABLE XLVII TITRATION OF N-DECANE-3 METHYLHEXANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Decane 3 Methylhexane Water Required Ml. Ml. Ml.

3.00 0.00 17.06 2.25 0.75 19.3^ 1.50 1.50 22.52 0.75 2.25 27.03 0.00 3.00 3^.16 123

TABLE XLVIII TITRATION OF N-DECANE-3 METHYLHEPTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Decane 3 Methylheptane Vr»ter Required Ml. Ml. Ml.

3.00 0.00 17.06 2.25 0.75 18.78 1.50 1.50 21.07 0.75 2.25 23.98 0.00 3.00 27.97 t

TABLE XLIX TITRATION OF N-DECANE-2,2 DIMETHYLBUTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Decane 2,2 Dimethylbutane Water Required Ml. Ml. Ml.

*f.00 0.00 13.8^ 3.00 1.00 16.36 2.00 2.00 20.1*f 1.00 3.00 26.3^ 0.00 ^.00 42.7^ \

FIGURE 36 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml.

Curve I - n-decane + 2,2,3 trimethylbutane volume, 3.00 ml.

Curve II - n-decane + 3 methylhexane volume, 3.00 ml.

Curve III - n-decane + 3 methylheptane volume, 3.00 ml.

Curve IV - n-decane + 2,2 dimethylbutane volume, ^f.OO ml.

12^ Water - ml. 40 30 20 550 25 yrcro B- % y volume by % - B Hydrocarbon 75 125 100 126

TABLE L TITRATION OF N-DODECANE-3 METHYLPENTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Dodecane 3 Methylpentane Water Required Ml. Ml. Ml.

3.00 0.00 11.85 2.25 0.75 14.24 1.50 1.50 17.95 0.75 2.25 24.77 0.00 3.00 42.83

TABLE LI TITRATION OF N-DODECANE-3 METHYLHEXANE- ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Dodecane 3 Methylhexane Water Required Ml. Ml. Ml.

3.00 0.00 11.85 2.25 0.75 14.00 1.50 , 1.50 17.19 0.75 2.25 22.65 0.00 3.00 34.16 127

TABLE LII TITRATION OF N-TETRADECANE-2 METHYLPENTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML. n-Tetradecane 2 Methylpentane Water Required Ml. Ml. Ml.

5.oo 0.00 8.36 2.25 0.75 10.26 1.50 1.50 13.3^ 0.75 2.25 19.65 0.00 3.00 ^3.2^

TABLE LIII TITRATION OF N-TETRADEC ANE-3 METHYLHEPTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML. n-Tetradecane 3 Methylheptane Water Required Ml. Ml. Ml.

3.00 0.00 8.36 2.25 0.75 10.08 1.50 1.50 12.56 0.75 2.25 17.10 0.00 3.00 27.97 FIGURE 37 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50»00 ml.

Curve I - n-dodecane + 3 methylpentane volume, 3*00 ml.

Curve II - n-dodecane + 3 methylhexane volume, 3*00 ml.

Curve III - n-tetradecane + 2 methylpentane volume, 3*00 ml.

Curve IV - n-tetradecane + 3 methylheptane volume, 3*00 ml.

128 E Water I 40 20 30 0 25 yrcro B b volume by % - B Hydrocarbon 50 E B 75 100 129 130

TABLE LIV TITRATION OF n-HEPTANE-2,2,3 THIMETHYLBUTANE-ISOPKOPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Heptane 2,2,3 Trimethylbutane Water Required Ml. Ml. Ml.

3.00 0.00 31.17 2.25 0.75 32.55 1.50 1.50 3 ^ 2 0.75 2.25 36.70 0.00 3.00 39.39

TABLE LV TITRATION OF n-HEPTANE-2,3 DIMETHYLPENTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML. n-Heptane 2,3 Dimethylpentane . Water Required Ml. Ml. Ml.

3.00 0.00 31.17 2.25 0.75 32.00 1.50 1.50 33.22 0.75 2.25 3^.61 0.00 3.00 36.30 151

TABLE LVI TITRATION OF 3 METHYLHEPTANE-2 METHYLPENTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

3 Methylheptane 2 Methylpentane Water Required Ml. Ml. Ml.

3.00 0.00 27.97 2.25 0.75 29.97 1.50 1.50 32.78 0.75 2.25 36.64 0.00 5.00 43.24

TABLE LVII TITRATION OF 3 METHYLHEPTANE-2,3 DIMETHYLPENTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

3 Methylheptane 2,3 Dimethylpentane Water Required Ml. Ml. Ml.

3.00 0.00 27.97 2.25 0.75 29.20 1.50 1.50 31.09 0.75 2.25 33.40 0.00 3.00 36.30 FIGURE J8 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml.

Curve I - n-heptane + 2,2,3 trimethylbutane volume, 3.00 ml.

Curve II - n-heptane + 2,3 dimethylpentane volume, 3.00 ml.

Curve III - 3 methylheptane + 2 methylpentane volume, 3.00 ml.

Curve IV - 3 methylheptane + 2,3 dimethylpentane volume, 3»00 ml.

1 3 2 E Water I 30 40 35 5 4 550 25 yrcro B % b volume by — % B Hydrocarbon 75 100 133 134

TABLE LVIII TITRATION OF 3 METHYLHEXANE-2 METHYLPENTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

3 Methylhexane 2 Methylpentane Water Required Ml. Ml. Ml.

3.00 0.00 34.16 2.25 0.75 35.36 1.50 1.50 37.16 0.75 2.25 39.38 0.00 3.00 43.24

TABLE LIX TITRATION OF n- HEXANE-2,2 DIMETHYLBUTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Hexane 2, 2 Dimethylbutane Water Required Ml. Ml. Ml.

4.00 0.00 33.30 3.00 1.00 34.86 2.00 2.00 36.71 1.00 3.00 39.83 0.00 4.00 42.74 135

TABLE LX TITRATION OF n-HEPTANE-n-HEXANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Heptane n-Hexane Water Required Ml. Ml. Ml.

3.00 0.00 31.17 2.25 0.75 32.60 1.50 1.50 3^.52 0.75 2.25 36.93 0.00 3.00 39.97

TABLE LXI TITRATION OF n-OCTANE-2,2,4 TRIMETHYLPENTANE-ISOPROPANOL MIXTURES HAVING A TOTAL DILUTION VOLUME OF 50.00 ML.

n-Octane 2,2,4 Trimethylpentane Water Required Ml. Ml. Ml.

3.00 0.00 25.32 2.25 0.75 26.43 1.50 1.50 28.02 0.75 2.25 29.88 0.00 3.00 31.89 FIGURE 39 Titration curves of certain binary aliphatic hydrocarbon mixtures having a total dilution volume of 50.00 ml.

Curve I - 3 methylhexane + 2 methylpentane volume, 3.00 ml.

Curve II - n-hexane + 2,2 dimethylbutane volume, 4.00 ml.

Curve III - n-heptane + n-hexane volume, 3*00 ml.

Curve IV - n-octane + 2,2,4 trimethylpentane volume, 3.00 ml.

136 Water - ml. 40 45 35 30 0 yrcro B- % y volume by % - B Hydrocarbon 50 51002575 137 EXPERIMENTAL RESULTS

Precision of results— aromatic mixtures

The precision of the titrations of samples composed of

two aromatic hydrocarbons and an alcohol varied both with the

total hydrocarbon content and with the relative per cent com­ position of the two hydrocarbons. A summary of the degree of precision for the titration of duplicate samples as a function

of the total volume of the two aromatic hydrocarbuons is given

in Tables LXII, LXIII, and LXIV. The titrations performed for

1.00 ml. benzene at 40.00 ml. and 50.00 ml. dilution with

ethanol and 1.00 ml. benzene at 50*00 ml • dilution with methanol

were not included in the precision tables because they were so

dilute in benzene that the appearance of turbidity was not at

all sharp and the precision between duplicate values was many

times lower than that for other dilutions.

It is seen in these tables that the degree of precision

was increased as the concentration of the hydrocarbons was in­

creased. This does not mean, however, that the accuracy of the method for the determination of the composition of binary hydro­

carbon mixtures was correspondingly increased with the increase

in hydrocarbon concentration as will be explained in the dis­

cussion of accuracy.

1 3 8 139

TABLE LXII SUMMARY OF THE DEGREE OF PRECISION AS A FUNCTION OF VOLUME OF AROMATIC HYDROCARBON-ETHANOL TITRATIONS

Total Total Average Volume Dilution Deviation Deviation A + B Volume Number of from Mean from Mean Ml. Ml. Titrations Ml. I«I1.

1.00 40.00 4l 1.79 0.043?

2.00 40.00 45 1.19 0 .026^

3.00 40.00 45 0.97 0 .021g

4.00 40.00 45 0.73 o.oi62

5.00 40.00 45 0.51 0 .011^

6.00 40.00 45 0.44 0.009g

1.00 50.00 4l 2.28 0.0556

2.00 50.00 45 1.19 0 .026^

3.00 50.00 45 0.83 0 .018^

4.00 50.00 45 1.00 0 .0222

5.00 50.00 45 0.72 o.oi60

6.00 50.00 45 0.51 0 .011, 5 i4o

TABLE LXIII SUMMARY OF THE DEGREE OF PRECISION AS A FUNCTION OF VOLUME OF AROMATIC HYDROCARBON-ISOPROPANOL TITRATIONS

Total Total Average Volume Dilution Deviation Deviation A + B Volume Number of from Mean from Mean Ml. Ml. Titrations Ml. Ml.

2.00 40.00 45 1.48 0 .032g

3.00 40.00 45 1 *Zfl 0.0313

4.oo 40.00 46 1.07 0.0233

5.00 4o;oo 45 0.84 o.oi8?

6.00 40.00 45 0.72 0 .0160

7.00 40.00 44 0.83 o.oi8q 7 8.oo 40.00 45 0.59 0.013

2.00 50.00 44 0.032* 1.43 5 3.00 50.00 45 1.31 0.0291

4.00 50.00 46 1.44 0.0313

5.00 50.00 45 1.07 0.023g

6.00 50.00 44 O.87 0.019g

7.00 50.00 44 1.10 0.0250

8.00 50.00 45 O.85 0.0i8o 7 141

TABLE LXIV SUMMARY OF THE DEGREE OF PRECISION AS A FUNCTION OF VOLUME OF AROMATIC HYDROCARBON-METHANOL TITRATIONS

Total Total Average Volume Dilution Deviation Deviation A + B Volume Number of from Mean from Mean Ml. _ Ml. Titrations Ml. Ml.

1.00 50.00 4l 1.71 0 .04l?

2.00 50.00 45 1.54 0 .0342

3.00 50.00 45 0.80 o.oi7g

4.00 50.00 46 1.02 0.0222

5.00 50.00 45 0.79 0 .0176

6.00 50.00 45 0.73 o .o i 62

1.00 60.00 4l 1.58 0.038,. 5 2.00 60.00 45 1.13 0.0253^

3.00 60.00 46 1.22 0.026.- 5 4.00 60.00 45 0.95 0 . 0 2 ^

5.00 60.00 45 0.84 0.0l8?

6.00 60.00 45 0.85 0.018 7 142

The summary of the degree of precision for the titration of duplicate samples as a function of per cent composition of

the two aromatic hydrocarbons is given in Tables LXV, LXVI, and

LXVII. It is seen in these tables that in most cases the degree

of precision was considerably less when the least soluble com­ ponent, that which is designated as B, was present as the pure

component. This was in part compensated by the fact that it was

this point which required the largest titration volumes. This

resulted in a lower relative error than otherwise indicated.

The slope of the curve was also generally greatest at this point which also resulted in a lower relative error.

Accuracy of results— aromatic mixtures

The accuracy of the method for the determination of the

composition of binary aromatic hydrocarbon mixtures by titration with water varied greatly not only with the particular hydro­

carbon pair but also with the total hydrocarbon concentration of

this particular pair. With this type of determination the

spread between that volume of water required to titrate a given volume of pure hydrocarbon A and that volume of water required

to titrate pure hydrocarbon B is the largest single factor af­

fecting the accuracy of the determination of the composition of

this hydrocarbon pair. The larger the difference in titration

volumes, the greater the accuracy becomes even though there may be a slight decrease in precision. 143

TABLE LXV SUMMARY OF THE DEGREE OF PRECISION AS A FUNCTION OF PER CENT COMPOSITION OF AROMATIC HYDROCARBON-ETHANOL TITRATIONS

Total Average Per Cent Dilution Deviation Deviation Composition Volume Number of from Mean from Mean % A Ml. Titrations Ml. Ml.

100 ^ 0.00 48 0.85 0.017?

75 40.00 60 0.86 0.014^

50 . 40.00 60 1.25 0.020g

25 40.00 6o 1.69 0. 0282

0 40.00 38 O.98 0.025g

100 50.00 48 1.06 0.0221

75 50.00 60 1.26 0.021o

50 50.00 60 1.43 0.023g

25 50.00 60 1.53 0.0255

0 50.00 38 I .25 0. 0329 TABLE LXVI SUMMARY OF THE DEGREE OF PRECISION AS A FUNCTION OF PER CENT COMPOSITION OF AROMATIC HYDROCARBON-ISOPROPANOL TITRATIONS

Total Average Per Cent Dilution Deviation Deviation Composition Volume Number of from Mean from Mean % A Ml. Titrations Ml. Ml.

100 4o.oo 57 1.56 0 .0239

75 40.00 70 1.17 0.0l6?

50 ^ 0.00 70 1.50 0.021^

25 40.00 70 1.40 0.0200

0 40.00 48 1.51 0 .0315

100 50.00 56 1.59 0.028^

50.00 70 1.52 0.018- 75 y 50 50.00 70 1.50 0.021^

25 50.00 70 1.73 0 .024?

0 50.00 47 1.93 0 .04^ 145

TABLE LXVII SUMMARY OF THE DEGREE OF PRECISION AS A FUNCTION OF PER CENT COMPOSITION OF AROMATIC HYDROCARBON-METHANOL TITRATIONS

Total Average Per Cent Dilution Deviation Deviation Composition Volume Number of from Mean from Mean % A Ml. Titrations Ml. Ml.

100 50.00 48 1.18 0 .0246

75 50.00 60 1.19 0 .0l9g

50 50.00 60 1.03 0.0172

25 50.00 60 1.60 0.026?

0 50.00 39 1.59 0 .040g

100 60.00 48 1.12 0 .0233

75 60.00 60 0.96 0.0160

50 60.00 60 1.48 0 .024?

25 60.00 60 1.46 0 .024^

0 60.00 39 1.55 0 .039? 146

An example of the accuracy of the method will be seen in

Table LXVTII which gives the absolute error in per cent by volume « for each of the aromatic hydrocarbons if the titration error is

/ assumed to be 0.10 ml. in magnitude. It will also be seen in

Table LXVIII that for mesitylene-benzene-ethanol solutions the smallest absolute error occurs when the concentration of the more soluble component, benzene, is in excess. This is expected

from the shape of the curves corresponding to the titration of

this mixture. These curves axe given in Figures 2 and 3 and it is seen that their slopes are increasing as the proportion of benzene in the mixture is increased. This effect is also noted in the aromatic hydrocarbon-methanol mixtures. However, in the case of the aromatic hydrocarbon-isopropanol mixtures, this effect is only observed when the total, hydrocarbon content is

4.00 ml. or less. Even then the effect is not nearly as great as in the aromatic hydrocarbon-ethanol and the aromatic hydro­ carbon-methanol mixtures. At a total hydrocarbon content of

5.00 ml. or more the greatest accuracy was between 25 and 75 per cent by volume of hydrocarbon A. An example of this is given in Table LXIX which shows the accuracy for the determination of the composition of mesitylene-benzene-isopropanol mixtures in

terms of absolute error in per cent by volume caused by a 0.10 ml. titration error.

When hydrocarbon B was toluene the spread in titration volumes was not as great as when hydrocarbon B was benzene.

Consequently the accuracy was not as great when toluene was one 147

TABLE LXVIII ABSOLUTE ERRORS FOR MESITYLENE-BENZEN E-ETHANOL MIXTURES CAUSED BY 0.10 ML. END POINT ERROR

Total Range in Percentage Composition jjLume uij.ui.ion I + B Volume 100-75 75-50 50-25 25-0 Ml. Ml. %k %A %k %k

1.00 40.00 0.84 0.53 0.30 0.09

2.00 40.00 0.94 , 0.61 0.39 0.18

3.00 40.00 1.05 0.73 0.45 0.25

4.00 40.00 1.19 0.82 0.53 0.31

5.00 40.00 1.29 0.93 0.60 O.38

6.00 40.00 1.47 1.02 0.69 0.45

1.00 50.00 0.63 0.39 0.24 o.o4

2.00 50.00 0.67 0.48 0.28 0.11

3.00 50.00 0.77 0.53 0.34 0.16

4.00 50.00 0.86 0.60 0.38 0.20

5.00 50.00 0.92 0.67 0.42 0.25

6.00 50.00 1.05 0.67 0.49 0.29 148

TABLE LXIX ABSOLUTE ERRORS FOR MESITYLENE-3ENZENE-ISOPROPANOL MIXTURES CAUSED BY 0.10 ML. END POINT ERROR

Total Range in Percentage Composition ijLume u j .x u no n . + B Volume 100-75 75-50 50-25 25-0 Ml. Ml. %A %A %A %A

2.00 4 0 .00- 0.55 0.40 0.29 0.19

3.00 40.00 0.58 0.43 0.34 0.27

4.00 40.00 0.60 0.47 0.39 0.38

5.00 40.00 0.67 0.51 0.47 0.51

6.00 40.00 0.73 0.55 0.56 0.72

7.00 40.00 0.78 0.62 0.66 0.94

8.oo 40.00 0.86 0.67 0.84 1.72

2.00 50.00 0.42 0.31 0.22 0.12

3.00 50.00 0.44 0.33 0.24 0.17

4.00 50.00 0.45 0.36 0,28 0.23

5.00 50.00 0.49 0.37 0.32 0.30

6.00 50.00 0.53 0.39 0.36 0.40

7.00 50.00 0.56 0.43 0.40 0.48

8.00 50.00 0.60 0.47 0.47 O.65 of the components as when benzene was one of the components.

Total titration spread in the titration of mesitylene-toluene- ethanol mixtures having a total dilution volume of 9-0.00 ml. ranged from 8.02 ml. when total hydrocarbon content was 6.00 ml. to 21.93 nil. when total hydrocarbon content was 1.00 ml. These same solutions when diluted to 50.00 ml. had a total spread from

11.80 ml. to 30.98 ml. The total spread in the titration of mesitylene-toluene-isopropanol solutions having a total dilution volume of 9-0.00 ml. was 7.53 ml* when the total hydrocarbon con­ tent was 8.00 ml. to 19*56 ml. when the total hydrocarbon content was 2.00 ml. These same solutions when diluted to 50.00 ml. had a range in spread from 13*32 ml. to 27.12 ml. The mixtures which involved p-cymene showed similar titration spreads to those which involved mesitylene. Those mixtures involving xylene and benzene gave about the same range in spread as did those of mesitylene and toluene. All the mixtures involving methanol gave spreads about equal to their corresponding mixtures with ethanol.

By a comparison of the data presented for the precision of the titrations as a function of volume and per cent compo­ sition with the data presented for the accuracy of the titrations with an assumed end point error, one can obtain a good estimate of the accuracy expected for a given sample. For example, a solution of mesitylene-benzene-ethanol having a total hydrocarbon content of 9.00 ml. and a dilution of 50*00 ml. would have a pre­ cision of about 0.022 ml. If this solution also contained ap­ proximately 50 per cent by volume of each substituent it would 150 have a precision of about 0.024 ml. Thus the overall precision would be about 0.023 ml. It is seen in Table LXVIII that 0.10 ml. error causes an absolute error of 0.49 per cent in the com­ position. This value of 0.49 per cent is computed by the average of the error over the 75-50 per cent mesitylene and the error over the 50-25 per cent mesitylene ranges. This would indicate that an average titration error would cause an absolute error of

0.11 per cent for each of the two hydrocarbon components.

In every system the greatest accuracy is observed* for the lowest total hydrocarbon range studied. However, the titra­ tion at this concentration was considerably more time consuming than those at higher concentrations. Therefore, in practice, one should pick the highest total hydrocarbon concentration in order to give results of the desired accuracy.

Precision and accuracy of results— aliphatic hydrocarbons

The degree of precision for the binary aliphatic hydro­ carbon mixtures is indicated in Table LXX. It will be seen from this table that again greater precision is obtained with inter­ mediate ranges of composition than with either extreme of com­ position. The accuracy of the determination of the composition of binary aliphatic mixtures which were studied varies much more than that for the aromatic mixtures.

The composition of mixtures of certain structural isomers were determined by the method of titration with water, but as was expected the accuracy was rather low. Curve I, Figure 39» shows 151

TABLE LXX SUMMARY OF THE DEGREE OF PRECISION AS A FUNCTION OF PER CENT COMPOSITION OF TITRATION OF ALIPHATIC HYDROCARBONS- ISOPROPANOL MIXTURES ALL WITH A TOTAL DILUTION VOLUME OF 50.00 ML.

Total Average Per Cent Deviation Deviation Composition Number of from Mean from Mean %A Titrations Ml. Ml.

100 38 0.88 0.0232

75 62 0.77 0 .012^

50 62 1.19 o.oi92

25 62 1.25 0 .0202

0 46 1.47 0.0320

the results for the titration cf n-heptane-2 ,2,3 trimethylbutane mixtures, Curve II, Figure 3 8 , shows the results for the titra­ tion of n-heptane-2,3 dimethylpentane mixtures, Curve II, Figure

3 9 , shows the results for the titration of n-hexane-2,2 dimethyl- butane mixtures, and Curve IV, Figure 39* shows the results of the titration of n-octane-2,2,4 trimethylpentane mixtures. The total titration spread over the complete 100 per cent range in composition was 8.22 ml., 5*15 ml., 9.44 ml., and 6.57 ml., respectively. This would give an average absolute error of

1 .2 2 , 1 .95* 1 .06 , and 1.52 per cent by volume, respectively, for an end point error of 0.10 ml.

The composition of binary mixtures in which the com­ ponents differed from each other by only one carbon atom was also determined by titration with water. Curve I, Figure 39* 152 shows the results for the titration of 3 methylhexane-2 methyl- pentane mixtures, Curve III, Figure 39> shows the results for the titration of n-heptane-n-hexane mixtures, and Curve IV,

Figure 3 8 , shows the results for the titration of 3 methyl- heptane-2,3 dimethylpentane mixtures. This latter mixture con­ sists of two components which not only differ in molecular weight by a single carbon atom but also differ in the degree of branching. The degree of accuracy is not as high with these pairs as it is with hydrocarbon pairs which are not as closely related in structure.

With many of the aliphatic hydrocarbon pairs, the degree of accuracy increases very rapidly as the per cent of hydro­ carbon B increases. This is especially seen in Curve IV, Figure

3 6 , where the difference between titration volumes for 75 per cent and 100 per cent 2,2 dimethylbutane is 16.40 ml. whereas that between 50 per cent and 75 Per cent 2,2 dimethylbutane is only 6.20 ml. and in Curve I, Figure 37* where the difference between titration volumes for 75 per cent and 100 per cent 3 methylpentane is 18.06 ml. whereas that between 50 per cent and

75 per cent 3 methylpentane is only 6.82 ml. There were several other mixtures in which the difference between titration volumes for 75 per cent B and 100 per cent B was around twice as large as the difference between 50 per cent B and 75 per cent B. In these cases it is apparent that the maximum accuracy occurs when hydrocarbon B is present at greater than 75 per cent by volume. 153

An overall summary of the precision of the titration of duplicate samples is given in Table LXXI. This table shows that the majority of the titrations agreed within 0.05 ml*

TABLE LXXI SUMMARY OF THE DEGREE OF PRECISION FOR ALL TITRATIONS OF BINARY HYDROCARBON MIXTURES

Agreement Between Number of Pairs Duplicate Samples Ml. of Results

0 .00-0.02 37^

0 .03-0.05 353

0 .06-0.08 198

0 .09-0.10 70

0 .10-0.15 53

over 0.15 12 THEORETICAL CONSIDERATIONS

The appearance of turbidity upon the addition of suf­ ficient water to a solution containing one or more components immiscible with water and a component which is both miscible with water and also a solvent for the components which are im­ miscible with water is due to the separation in a minutely divided state of a second phase. This second phase has physical properties vastly different from those of the bulk of the solution thus causing turbidity when intimately dispersed in the bulk of the solution. When the mixtures contain two hydrocarbons, the one that separates first and causes the appearance of turbidity is the hydrocarbon which is least soluble in the alcohol. If additional water is added past the end point the separated phase will eventually consist predominately of a mixture of the two hydrocarbons. For example, if a mixture of mesitylene-benzene- ethanol is titrated with water to the first appearance of tur­ bidity, the separated phase consists of mesitylene with traces of ethanol and water. When additional water is added to the solution the second phase consists of a large amount of mesity­ lene, some benzene, and again traces of ethanol and water. In this work, however, all titrations were stopped after the ap­ pearance of turbidity sufficient either to obscure the ther­ mometer in titrations involving aromatic hydrocarbon mixtures

15^ 155 or to obscure the lettering on the manufacturer's name plate behind the titration cell in titrations involving aliphatic hydrocarbon mixtures. Consequently, no titrations were carried to the point where the second hydrocarbon appeared in the second phase.

When water is added to an alcohol solution heat is evolved. This evolution of heat is due to the formation of hydrates of the alcohols through the formation of hydrogen bonding. In this type of hydrogen bonding the hydrogen atom of the hydroxyl group of the alcohol acts as the acceptor and the oxygen atom of the water acts as the donor. Thus the addition of water causes the alcohol molecules to be bound with the water molecules making the alcohol an ineffective solvent for any nonpolar, or slightly polar liquid in the system. When enough water is added to tie up effectively a sufficient proportion of the alcohol, the alcohol becomes ineffective for solvation of all of the nonpolar or slightly polar liquid in the solution.

It is this effect which causes the separation of the second phase. SUMMARY

It has been shown in this work that the quantitative

composition of a binary hydrocarbon mixture may be determined by dissolving a known volume of the binary mixture in a known volume of alcohol and titrating the resulting solution with water to the appearance of turbidity at constant temperature.

It was shown that if the proper concentration range is selected

the composition of the binary mixture may be determined to a high degree of accuracy. It was also shown that the precision of the method is high. It was shown that in nearly every mixture

the greatest accuracy occurred when the■hydrocarbon most soluble in the alcohol was present in excess. When the least soluble

component was in excess the accuracy could be improved by the addition of a given amount of the pure component with the higher

solubility before the titration was performed. A simple cal­

culation would then give the original concentration of the mixture.

This general technique may have considerable application in industry, especially in the area of control analysis. A

technique could be worked out for the determination of the quantitative composition of many different types of binary mixtures if these mixtures were essentially free of impurities.

The technique would involve the selection of two solvents, one

156 157 in which both of the components to be determined would be in­ soluble or only slightly soluble, and the other a solvent in which both of the components were soluble but not to the same degree. Then by selecting a proper temperature and concentration range a suitable procedure could be developed.

The chief advantages of this type of method is that once the conditions are established and standard samples are run it is fairly rapid, requires only a small amount of inexpensive apparatus, and a skilled technician can easily be trained to perform the work. An additional advantage for commercial use is that the method can easily be adapted to automation. An auto­ matic titration could be performed with the end point being de­ tected by means of a photoelectric cell. Contrary to other titrimetric methods of analysis, this procedure does not require the preparation of a standard solution as a titrant other than a reproducible grade of distilled water, without which any chemical laboratory could not function.

The chief disadvantage to this method is that as with any indirect method of analysis the presence of any impurities in either of the components being determined would cause an error.

Depending upon the properties of the impurity, the titration volume could be either high or low. Another disadvantage is that the volume of water required to produce turbidity is temperature dependent. However, it was shown that if the temperature is closely controlled this effect can be eliminated. BIBLIOGRAPHY

Bogin, C. D., Ind. Eng. Chem., 16 (1924), pp. 38O-6 .

Caley, E. R., and Habboush, A., Anal. Chem., 33 (1961), pp. 1613-16.

Habboush, A., "Determination of the composition of mixtures of organic liquids by physical titration with water," (Ph.D. dissertation, The Ohio State University, 1959).

Hodgson, H. W., and Clover, J. H., Analyst, 76 (1951), pp. 635-4-3.

Holt, Alfred, and Bell, Norman M., J. Chem. Soc., 105 (1914), pp. 633-9 .

Jones, D. C., and Amsteil, S., J. Chem. Soc., (1930), pp. 1316-23.

Kimura, T., C . A ., 47 (1935)» p. 5844; Ann. Repts. Takeda Research Lab., 11 (1952), pp. 61-73.

Robertson, G. R., Ind. Eng. Chem. Anal. Ed., 15 (1943), pp. 451-2.

Sidgwick, N. V., and Spurrell, W. J., J. Am. Chem. Soc., 117 (1920), pp. 1397-1404.

Siggia, S., and Hanna, J. G., Anal. Chem., 21 (1949), pp. 1086-9.

Smith, A. S., Ind. Eng. Chem., 37 (1945)1 PP» 185-7.

Spiridonova, S. I., Zhur.. Obshchei Khim., 7 (1937), pp. 1071-81.

______., Zhur. Priklad. Khim.,13 (1940), pp. 1169-77.

______. 1 ibid., 14 (1941), pp. 646-51.

______., ibid., 19(1946), pp. 966-72.

______., ibid., 20 (1947), pp. 635-41.

______., ibid., 21(1948), pp. 948-53.

______., Zhur. Anal. Khim., 4 (1949), pp. 169-72.

______., Zhur. Fiz. Khim., 26 (1952), pp. 1827-33.

158 159

Spiridonova, S. I., Zhur. Priklad. Khim., 25 (1952), pp. 429-34.

______., ibid., 22 (1949), pp. 1284-91.

______.1 Zhur. Fiz. Khim., 29 (1955), PP. 159-65.

Spiridonova, S. I., and Nikitin, E. K., C. A ., 53 (1959), p. 9788; Izvest. Vysshykh Ucheb. Zavedenii Khim. i Khim. Teknol., (1958), pp. 22-7. :

Tarasenkov, D. N., and Paul'sen, I. A., Zhur. Obahchei Khim., 7 (1937), pp. 2143-8.

Walton, J. K., and Jenkins, J. D., J. Am. Chem. Soc., 45 (1923), P. 2559.

Washburn, E. R., and Beguin, A. E., J. Am. Chem. Soc., 62 (1940), pp. 579-81.

., ibid., 62 (1940), pp. 1454-7.

Washburn, E. R., Beguin, A. E., and Bechord, 0. C., ibid., 6l (1939), pp. 1694-5.

Washburn, E. R., Brockway, C. E., Graham, C. L., and Deming, P., ibid., 64 (1942), pp. 1886-8 .

V/ashburn, E. R., Hnizda, V., and Void, R. D., ibid., 53 (1931), pp. 3237-44.

Washburn, E. R., and Olsen, A. L., ibid., 57 (1935), pp. 303-5*

Washburn, E. R., and Mason, L. S., ibid., 59 (1937), pp. 2076-7.

Washburn, E. R., and Simonsen, D. R., ibid., 68 (1946), pp. 235-7.

Washburn, E. R., and Spencer, H. C., ibid., 56 (1934), pp. 361-4.

V/ashburn, E. R., and Void, R. D., ibid., 54 (1932), pp. 4217-25. AUTOBIOGRAPHY

I, Larry Eugene Wilson, was born on November 17, 1935» near Waynesfield, Ohio. I received my elementary and high school training in the public school of Waynesfield, graduating in May

1953. In September of 1953» I enrolled in the College of Arts and Sciences of The Ohio State University. I received my

Bachelor of Science degree in June 1957* In September 1957» I enrolled in the Graduate School of The Ohio State University.

While attending Graduate School, I held the following Chemistry

Department appointments: Assistant, October 1957 to June 1958;

Research Fellow, July to September 1958; Assistant, October 1958 to September 1959; Standard Oil of Ohio Fellowship, October 1959 to June I960; Assistant, July I960 to September I960; Assistant

Instructor, October i960 to June 1961; -Esso Fellowship, July

1961 to March 1962; Instructor, Part-time, April 1962 to June

1962; Assistant, July 1962 to September 1962; Assistant In­ structor, October 1962 to March 1963*

1 6 0