616
INDUSTRIAL AND ENGINEERING CHEMISTRY
octane; but the samples had mainly been purified with meticulous care by prolonged fractional distillation, fractional crystallization and chlorosulfonic acid treatment. If equal care were used in purifying samples, hydrocarbon vapor pressures would show better correlation. It was also brought out in the previous article ( 2 ) that methane and ethane were not correlative with the rest of the series as regards boiling points; therefore it is not surprising that they are not correlative as regards other thermodynamic properties. The chief use of the equations given would be to determine accurately certain key points for the plotting of curves. They could be plotted on charts with the pressure axis logarithmic and the temperature axis laid off arbitrarily to make the steam curve a straight line, as suggested several years ago (3). It would be better still, probably, to lay off the temperature axis proportional to 1/T since this value is easily calculated. In either case most of the lines, though nearly straight, would have a slight curvature. With four points determined, they could be plotted with as good precision as desired.
VOL. 28, NO. 5
Literature Cited (1) Beattie, Poffenberger, and Hadlock, J . Chem. Phys., 3,96 (1936). (2) Cox, E.R.,IND. ENG.CHEX.,27, 1423 (1935). (3) Ibid., 15, 592 (1923). (4) Cragoe, C. S., International Critical Tables, Vol. 111, p. 246, New York, McGraw-Hill Book Co., 1928. (5) Dana, Jenkins, Burdick, and Timm, Refrigerating Eng., 12,387 (1926). (6) International Critical Tables, Vol. 111, pp. 201, 207, 208, 213, 215, New York, McGraw-Hill Book Co., 1928. (7) Kuenen, Communications P h y s . Lab. Univ. Leiden, 125 (1911). (8) Leslie and Carr, IND. ENG.CHEM.,17, 814 (1925). (9) Mathews, J. Am. Chem. SOC.,48, 562 (1926). (10) Mundell, 2. p h y s i k . Chem., 85,435 (1913). (11) Ormandy and Craven, J. I n s t . Petroleum Tech., 9,33 (1923). (12) Sage, Schaafsma, and Lacey, IXD. ENQ.CHEM.,26, 1219 (1934). (13) Seibert and Burrell, J. Am. Chem. Soc., 37, 2683 (1915). (14) Thiesen, Wied. Ann. [N. F.],67, 692 (1899). (15) Timmermans, International Critical Tables, Vol. 111, p. 244, New York, McGraw-Hill Book Co., 1928. (16) Woringer, 2. physik. Chem., 34, 257, 262 (1900). (17) Young, Sci. Proc. R o y . D u b l i n SOC.,12,389 (1909-10). RECEIVED December 4, 1935
Miscibility of Alcohol and Oils T. IVAN TAYLOR, LESLIE LARSON, AND WAYNNE JOHNSON University of Idaho,Moscow, Idaho
PHASE-RULE study of various systems consisting of oils, alcohol, and a third liquid has been in progress a t this laboratory. At the beginning of the investigation concordant data giving quantitative statements of the miscibility of alcohol with oils were difficult to find except for a few of the most common ones. Miscibility determinations for most of the oils being used were made, therefore, a t the outset to determine the oils most suitable for the study. The results of these measurements are being reported a t this time, since the work will be interrupted. Thecompletedataon some of the ternary systems will be reported later. Davidson and Wrage ( I ) found that the niiscibility of oils and alcohol was affected by free fatty acid. A knowledge of the free fatty acid content Oil of the oils is, then, of importancein comparing Almond sweet solubility data of oils. According to Lewkowitch (5) the acid value is variable and depends upon Apricot-kernel the quality of the oil, which in turn varies with the purity of the oil, the age, the extent of hydrolysis, and the amount of oxidation. The acid China wood value is not necessarily, as pointed out by Jamieson ( 3 ) ,a measure of rancidity. Since it is genCod liver erally true that there is more alcohol entering the oil phase than there is oil entering the alcohol phase, it is important to have data for both phases. Corn By gradually adding oleic acid or castor oil, both of which are completely miscible with alcoLinseed hol a t room temperatures, complete miscibility resulted when a definite amount had been added. Neat's-foot These values for different proportions of alcohol and oil may be used in certain cases to help identify oils or help determine their adulteration. Olive It was also interesting to observe the type and stability of the emulsions produced with varying Peach-kernel proportions of alcohol and oils; moreover, many examples of inversion and multiple-type emulsions were observed.
Materials The oils were all of as good grade as could be obtained on the market. The small acid values (Table I) for most of the oils show that they had not undergone more than normal hydrolysis and were of good quality. Absolute alcohol with a density of 0.78515 a t 25' C. was prepared by digesting three times with calcium oxide. A solution containing nearly 90 per cent alcohol by weight and having a density of 0.81282 a t
-
TABLEI. PROPERTIES OF OILS Specific Gravity 25'/4' d.
Refractive Acid Value Index Mg. KOH/G. 25' C.' 011
Per Cent Oleic Acid for Acidity Complete Miscibility as Oleic Abs. Acid al%?ol alcohol
cc .
cc.
0.9112
1.4701
0.60
0.30
8.18a 8.30 7.81
2.72Q 2.60 1.88
0.9126
1.4701
0.10
0.05
8.10 8.34 7.80
2.70 2.66 1.87
0.9346
1.5162
7.80
3.92
7.68 7.46 6.14
1.78 1.80 1.30
0.5199
1.4772
1.00
0.60
8.31 8.42 7.89
2.92 2.72 1.92
0.9110
1.4707
3.98
2.00
6.86 7.00 6.68
2.00 2.00 1.40
0.9251
1.4781
1.95
0.98
7.30 7.60 0.71
2.1% 1.80 1.18
0.8937
1.4684
6.11
3.07
7.12 7.15 6.44
2.05 1.68
0.5086
1.4677
1.03
0.62
8.12 8.21 7.50
2.81 2.43 1.71
1.4701
0.29
0.15
7.41 7 60 6.85
2.58 2.56 1.70
0.9100
1.02
.
MAY, 1936
INDUSTRIAL AND ENGINEERING CHEMISTRY
25" C. was prepared by adding distilled water to 95 per cent alcohol.
Experimental Results The acid number of each oil was determined by the method outlined by Jamieson (4) and was calculated to percentage acidity as oleic acid. These values, together with the refractive index of the oils at 25" C. and the volume of oleic acid just necessary to cause complete miscibility of the alcohol and oils at 25.0" * 0.3" C., are given in Table I. The volumes chosen for the miscibility tests were such that the ratio of oil to alcohol was 1 to 2 , 1 to 1, and 2 to 1. As an increasing volume of oleic acid was added to the mixture, the volume of the alcohol phase decreased until it finally disappeared and complete miscibility resulted. Miscibility data were obtained after shaking the samples vigorously with a motor shaker for 4 hours in the air thermostat regulated to 25.0" * 0.3" C. This temperature is below the Crismer value ( 2 ) for all the oils except castor oil and oil of bitter almond, and represents an average room temperature. The samples were allowed to stand overnight, or longer in some cases, for settling and observation of type and stability of emulsion formed. Volume measurements were taken from the 100-cc. graduates in which the samples were shaken. Density determinations a t 25.0" C. were carefully made for each layer before and after mixing by use of a small glass-bulb pycnometer. The usual precautions for such density measurements were taken. Refractive indices of all phases were measured to determine whether or not any correlation existed between them and the concentration changes in each phase. In most cases there were small regular changes, but the values were considered to be of little practical value. Calculations were made from the above measurements and are reported on a weight basis in Table I1 in accordance with the suggestions of Seidell(6). Volume solubilities may be easily calculated from these results if desired. The following equations, which are useful in calculating the percentage composition by weight of other liquid mixtures from density measurements where little or no change in volume occurs in mixing, were used to calculate the results:
617
Per cent oil in alcohol phase = (density oil) (density alcohol phase - density alcohol) (density alcohol phase) (density oil - density alcohol) Per cent alcohol in oil phase = (density alcohol)(density oil - density oil phase) (density oil phase) (density oil - density alcohol)
( 1)
(2)
These equations may be written in the general form, Per cent A in mixture C of A and B = (a)(c
- b,
(c)(a - b)
where a, b, and c represent the density of A , B, and C, respectively. The calculations were made on the assumption that the oil going into solution had the same density as the oil sample. That this assumption is nearly true is supported by the experiments of Davidson and Wrage ( I ) , in which they studied the solubility of different glyceryl esters and the distribution of free fatty acid in the alcohol and oil phase. It should be recognized, however, that the variation and uncertainty in the composition of the oils are factors to be considered in evaluating and comparing the results.
Discussion
The extent of the miscibility of alcohol and oils seems to be characteristic for each oil. The acid value is important, but a comparison of the values given in Table I with the miscibilities show that it is not the determining factor. High acid values increase the miscibility and also markedly increase the stability of the emulsions produced during shaking. A comparison of the normal iodine value of the oils with the solubility shows that there is no correlation between unsaturation and the miscibility of the oils. In general there is two to three times as much alcohol going into the oil phase as there is oil going into the alcohol phase. Also more oil generally goes into the alcohol phase when the ratio of alcohol to oil is least. This may seem to indicate that some certain component of the oil is most readily dissolved by the alcohol, but it is not necessarily true. There is no regular variation in the amount of alcohol going into the oil phase with change in the ratio of alcohol to oil. The amount of alcohol dissolved TABLE I (Continued) and the variation with change in ratio seems to be Per Cent Oleic Acid for Refractive Acid Value Acidit,y Complete Miscibility Specific characteristic of the oil. The solubility of the Mg. KOH/G. as Oleic 90% Abs. Index, Gravity, alcohol in the oil is more constant with change in Oil Acid alcohol alcohol 25' C. Oil 25'/4' C. cc. cc . ratio than is the solubility of oil in alcohol, 1.4695 0.48 0.24 7.40 2.65 0.9099 Peanut Many examples show the importance of phase7.48 2.70 volume ratio in determining the type of emulsion 6.80 1.88 formed. In many cases, particularly when equal 1.4735 1.01 0.51 7.55 2.25 0,9177 Poppy-seed 7.65 2.01 amounts of alcohol and oil were used, multiple6.94 1.39 type emulsions were observed. Often, when 0.9085 1.4705 0.78 0.39 9.28 3.90 Rapeseed adding increasing volumes of oleic acid, we obtain 9.15 3.60 8.22 2.56 first a multiple type and then an inversion. Increasing volumes of oleic acid when added to a 1,4719 0.24 0.12 8.10 2.88 Sesame 0,9178 7.90 2.60 mixture of alcohol and oil gradually decrease the 7.50 1.68 volume of the alcohol phase and the stability and 1.4735 0.29 0.15 8.02 2.54 0.9163 Joy-bean fineness of the emulsion formed until finally the 8.35 2.35 7.62 1.70 solution is just cloudy and then clear. Apparently there is first an inversion of emulsion type from Sunflower 0.9241 1.4809 2.09 1.05 6.40 1.78 6.92 1.80 oil in alcohol to alcohol in oil and then a gradual 6.40 1.30 decrease in size of droplets to molecular dimenWalnut 0.9186 1.4757 7.39 3.72 6.54 1.66 sions when a complete solution results. In this 6.63 1.50 6.10 0.98 approach to or just beyond the range of colloidality may lie the explanation for part of the Whale 0.9145 1.4748 2.10 1.06 7.35 2.60 7.58 2.49 change in miscibility with change in ratio, though 6.95 1.60 the solution of a particular component of a In each case first figure represents results with 7 cc. of oil and 14 cc. of alcohol; second, the oil is probably responsible for most of the 10.5 cc. of oil anh 10.5 cc. of alcohol; and third, 14 cc. of oil and 7 cc. of alcohol. change.
VOL. 28, NO. 5
INDUSTRIAL AND ENGINEERING CHEMISTRY
618
TABLE11. MISCIBILITY OF ALCOHOL AND OIL % Alcohol by Weight, Sp. Gr. 25’/4’ = 0.81282-MlsClbllity-Oil in Alcohol Type 100 g. in 100 Vol. of phases of Stabilit Sp gr 25°/;;1 C. alcohol g. oil dlcohol Oil emul- time.o8’ Alo0i;ol phase phase phase phase aion settling phase phase 7
Oil
9
0
-
-
Absolute Alcohol,.Sp. Gr. 25O/4O 0.78515 -MiscibilityOil in Alcohol Stabilit 100 g. in 100 Vol. of p h a y sp Alcogol gr 250/6;lc’ alcohol g. oil Alcohol Oil emul- time.o? phase phase phase phase phase phase aion settling
T:fe
Min.
Min. 30 60
Grams
Gams
Grams
Grams
Almondsweet 0.8138’ 0.9024 0.8147 0.9021 0.8182 0.9023
1.14 2.16 6.11
8.06 8.33 8.15
44.8 28.0 11.7
15.2 32.0 48.3
OA A0 A0
300 30 300
0.7907” 0.8898 0.7914 0.8912 0.7928 0.8902
5.03 5.67 6.93
14.99 13.98 14.70
44.6 24.1 7.3
15.6 34.9 62.7
OA A0 A0
Apricot-kernel 0.8143 0.9034 0.8151 0.9033 0.8180 0.9040
1.69 2.69 5.81
8.30 8.39 7.75
44.4 28.0 12.2
15.6 32.0 47.8
OA
OA
45 35 20
0.7900 0.8906 0.7911 0.8908 0.7922 0.8914
4.35 6.34 6.33
16.23 15.09 14.62
44.8 25.2 8.0
15.2 34.8 64.0
OA OA
China wood
1.41
... ...
7.80
... ...
44.6 29.0
15.4 31.0
OA OA
12 15 Notin 1 wk.
0.7963 0.9114 0.7989 0.9099
8.72 10.72
13.38 14.27
44.5 24.0
16.6 36.0
OA OA
0.8140 0.9111 0.8148 0.9114 0.8178 0.9114
1.27 2.11 5.25
7.33 7.08 7.08
44.1 26.5 11.0
15.9 33.6 49.0
A0
OA OA
... ... ...
0.7906 0.9006 0.7910 0.9006 0.7928 0.9015
4.66 5.01 6.55
12.49 12.49 11.90
45.0 26.2 8.1
15.0 33.8 51.9
OA A0 A0
... ... ...
0.8130 0,9028 0.8145 0.9026 0.8192 0.9019
0.23 1.94 7.25
7.52 7.70 8.35
45.1 27.5 10.2
14.9 32.5 49.8
OA
8 12 30
0.7935 0.8905 0.7973 0.8890
7.57 10.90
14.36 15.45
...
46.1 26.1 5.0
15.9 33.9 55.0
OA OA OA
25
0.8150 0.9127 0.8170 0.9128 0.8231 0,9129
2.22 4.24 10.30
9.84 9.76 9.68
44.4 27.3 11.0
15.6 32.7 49.0
OA OA A0
7
0.7970 0.8959 0.7997 0,8940 0,8045 0.8976
9.78 11.99 15.86
18.29 19.52 17.26
46.0 24.2 4.4
14.0 35.8 55.6
OA OA A0
0.8150 0.8843 0.8174 0.8849 0.8215 0.8846
2.98 6.22 11.70
10.64 10.98 10.33
....
.. .. ..
OA A0 A0
...6
0.7943 0.8753 0.7991 0.8722 0.8703
9.43 14.32
...
15.22 17.83 19.45
....
.. .. ..
A0 A0
4 20
0.8141 0.8997 0.8156 0.8994 0.8183 0.9002
1.53 3.26 6.38
8.31 8.59 7.83
44.5 28.8 11.7
15.5 31.2 48.3
OA OA A0
15 15 10
0.7908 0,8874 0.7922 0.8868 0.7934 0.8880
6.22 6.51 7.62
15.15 15.59 16.17
44.5 25.2 6.4
16.6 34.8 63.6
OA OA
4 4 6
........ .. .. .. .. .. .. .. ..
... ... ...
... ...
.. ..
0,7897 0.8902 0.7904 0,8903 0.7896 0.8906
4.16 4.79 4.06
14.00 13.98 13.71
43.1 24.8 7.8
16.9 35.2 52.2
OA
OA
2 3 60
... ...
8.74 9.11
48;O
0.7901 0,8875 0.7905 0.8892
4.63 4.92
15.91 14.46
45;4
14.6
..
OA OA
...
0.8143 0.9238 b
b
Codliver Corn Linseed
Neat’s-foot
Olive
Peach-kernel Peanut
b ....
.... ....
0.9005 0.9001
...
..
0
..
OA
.....
OA OA
........
....
7
Notin 12 hr. 4
....
. . . . . . . . .. .. .. .. .. .. .. .. 12.0 OA 85 . . OA Not in 1 wk.
...
...
...
..
0
..
A0
...
OA
A0
A0
300 6 7 120 3 5 Not in 1 wk.
8
7 7
7 Not in 12 hr.
1
60 Not in 1 wk. 90
11.57
28.0
32.0
A0
120
...
14.46
17.0
43.0
A0
Poppy-seed
0.8145 0.9071 0.8157 0.9069 0.8194 0.9075
1.83 3.11 7.05
9.05 9.23 8.71
44.2 27.3 11.2
15.8 32.7 48.8
OA A0 A0
10 3 Not in 5 hr.
0.7934 0.8926 0.7952 0.8917 0,7967 0,8928
7.16 8.70 10.00
16.67 17.28 15.53
45.0 24.8 4.9
16.0 35.2 55.1
OA A0 A0
10 20 300
Rapeseed
0.8140 0.8994 0.8150 0.8993 0.8182 0.9003
1.40 2.56 6.27
8.57 8.67 7.74
44.3 27.8 12.0
15 7 32.2 48.0
OA
OA
15 15 60
0.7889 0.8893 0.7897 0.8895 0.7914 0.8897
3.46 4.20 5.77
13.76 13.61 13.46
44.0 26.9 8.0
16.0 34.1 52.0
OA OA A0
5 12 30
0.8146 0.8986 0.8160 0.9069 0.8195 0.9081
1.93 3.43 7.15
16.54 9.31 8.27
44.1 28.0 12.0
OA
48.0
OA A0
... ... ...
0.7911 0.8959 0 7919 0 8964 0 7941 0.8975
5.16 5.86 7.85
14.47 14.07 13.40
45.0 25.9 8.2
15.0 34.1 15.8
OA A0 A0
... ... ...
Soy-bean
0.8138 0.9068 0.8152 0.9072 0.8181 0.9078
1.09 2.60 4.56
8.23 7.88 7.35
44.8 28.0 11.4
15.2 32.0 48.6
OA OA A0
2 2 10
0.7921 0 8934 0.7929 0,8938 0.7933 0.8943
6.09 6.79 6.14
15.35 15.08 14.72
44.7 25.5 6.0
15.3 34.5 54.0
OA OA A0
2 2 7
Sunflower
0.8133 0.9153 0.8146 0.9147 0.8197 0.9158
0.51 1.83 6.99
7.02 7.51 6.64
44.5 27.8 10.0
15.5 32.2 50.0
OA OA
6 16 8
0.7955 0.8998 0,7988 0.8984 0.8016 0.8979
8.61 11.86 13.61
15.24 16.16 16.49
46 0 24.8 4.1
14.0 35.2 55.9
OA OA A0
3 12 5
0.9073 o:si39 0.9062 0.8182 0.9061
i:i7 6.69
9.57 10.52 10.60
44.1 27.4 9.1
15.9 32.6 51.9
OA OA
OA
20 17 28
0.7941 0.8920 0.7976 0.8888 d 0.8900
8.29 11.50
...
18.98 21.33 20.43
45.9 26.0 2.6
14.1 35.0 57.5
OA OA
OA
6 12 20
0.9058 o:iii2 0.9061 0.8157 0.9060
2.65 3.20
7.68 7.41 7.50
42.4 28.0 11.8
17.6 32.0 48 2
OA OA A0
17 20 31
0.7906 0.8952 0.7907 0.8947 0.7937 0.8952
4.74 4.92 7.67
13.09 13.45 13.09
44.5 26.2 7.0
15.6 33.8 53.0
OA OA A0
46 12 120
....
Sesame
Walnut
Whale
0.8975
...
15 9 32.0
A0
A0
b
0.8892
In each case first figure represents result with 45 cc. of alcohol and 15 cc. of oil: second, 30 CC. of aloohol and 30 cc. of oil; and third, 15 co. of alcohol and 45 cc. of oil. b Stable emulsion formed with alcohol phase remaining cloudy. 0 A white milky layer reiained indefinitely between phases. d Alcohol phase not large enough for sample.
Table I indicates that more oleic acid is generally required to make equal volumes of 90 per cent alcohol and oil completely miscible than for either greater or less ratios. The complete phase-rule diagrams for these systems will be interesting. The influence of small amounts of water on the miscibility of alcohol and oils can readily be seen from these results. It always takes less oleic acid to bring about complete miscibility the less the ratio of absolute alcohol to oil, indicating that the process of bringing the alcohol into the oil phase is the controlling factor for complete miscibility.
Literature Cited (1) Davidson and Wrage, Chem. Rev. Fett.- HaTz.-Ind., 22,9 (1915). (2) Fryer and Weston, Analyst, 43, 3 (1918). (3) Jamieson, “Vegetable Fats and Oils,” p. 27, New York, Chemical Catalog Co., 1932. (4) Ibid.,p. 338. (5) Lewkowitch, “Chemical Technology and Analysis of Oils, Fats, and Waxes,” 5th ed., Vol. 1, p. 440,London, Macmillan Co., 1921. (6) Seidell, “Solubilities of Inorganic and Organio Compounds,” 2nd ed., Vol. 1, p. XI, New York, Van NostrandCo., 1919.
R~CIUIV January ~D 10, 1936.
