December, 1944
INDUSTRIAL AND ENGINEERING CHEMISTRY ACKNOWLEDGMENT
The authors are especially grateful to R. Petemon and T.p. Caldwell of this Laboratory for the preparation of several large samples of caaein fiber, without which this investigation could not have been made; they also wish to acknowledge msistance given by Clare M. McGrory of this Laboratory.
117s
Kise, M. A., and Carr, E. L., Taztile Rasearch. 7 , 103-9 (1936); Carr, Edward, Il@., 8, 125-33 (1938). (8) McMeekin, T. L.,and Warner, R. C., J . Am. Chm. sot., 64, (7)
2393-8 (1942); A S T M Bull. 125, 19-21 (1943).
(9) Millson, H.E., Cdco Tech.Bull. 667, (1942). (10) Rath, H., and Essig, A., Klepzig’s Teztil-Z., 41, 463-6 (1938). (11) Sakami, W., and Toennies, G., J . BioE. Chem., 144, 203-5 (1942). (12) Sheppard,S. E., and Newsome, P. T., J. Phgs. Chem., 33, 1817-
.----,
36 _ - f 1928).
LITERATURE CITED
a
Atlantic Research Associates, Brit. Patent 536,841 (May 29, 1941); Atwood, F. C., U. 8.Patent 2,342,634 (Feb. 29, 1944). Carr, Edward, Teztile Research, 8, 399-405 (1938). Elliott, G. H., and Speakman, J. B., J . SOC.Dyers Colourists, 59, 186-91 (1943).
Gebhard, K., 2.angew. Chem., 27, 302-4 (1914). Gordon, W. G., et al. (in course of preparation). Hendrix, B. M.. and Paquin, F., Jr., J . Biol. C h m . , 124, 136-45 (1938).
Sutermeister, Edwin, and Browne, F. L., “Casein and Its Industrial Applications”, A.C.S. Monograph 30, 2nd ed., p. 158, New York. Reinhold Pub. Corp,, 1939. (14) Traill, David (to Imperial Chemical Industries), Brit. Patent, (13)
492,895 (Sept. 26, 1938). (16) Ibid., 496,332 (Nov. 10, 1938). (16) Worrnell, R. L. (to Courtauld’s Ltd.), Ibid., 495,885 1938).
(Nov. 22.
PRXISXINTED before the Division of Industrial and Engineering Cbemistry at CHEMICAL SOCIETY, Cleveland, Ohio. the 107th Meeting of the AMERICAN
Carbon TetrachlorideTetrachloroethvlene Svstern J
J
VAPOR PRESSURE AND LIQUID-VAPOR COMPOSITION HUGH J. McDONALD AND WILLIAM R. McMILLANl Illinois Institute of Technology, Chicago, Ill.
The liquid-vapor composition for the binary system carbon tetrachloride-tetrachloroethylene has been determined. The vapor pressure data are obtained by determining the boiling points at four different pressures of nine samples covering the binary diagram. The boiling points of the system at 1 atmosphere pressure and the vapor pressure at 60”C. are given.
twice to the original sample, and the procedure was repeated. The temperature-pressure data thus obtained make up the first four lines in each section of columns 1 and 2, Table 11. A similar procedure WM followed with carbon tetrachloride as the initial sample. Tetrachloroethylene was added five times. These data make up the first four lines in each section of columna 5 and 0 and of 9 and 10. The system waa covered with a total of thirty-six vapor pressure measurements on nine samples. The
I
N T H E course of investigations on liquid mixtures in this laboratory, the industrially important system carbon tetrachloride-tetrachloroethylene was studied. It was felt that data gathered on this mixture would be of interest to handlers of commercial solvents, especially to those who manufacture tetrachloroethylene from carbon tetrachloride and therefore have a separation problem. The preparation and quality of the carbon tetrachloride and tetrachloroethylene and the method of analysis of samples were reported previously (8). The apparatus for determining the vapor composition (1, 9) and the vapor pressure have already been described (4). To obtain the liquid-vapor composition, samples of approximately 50 ml. were made up by weight at exactly 0.1 mole fractions and were allowed to come to boiling equilibrium before being distilled (2). A few drops were then distilled, and the analysis of this distillate waa taken as the vapor composition for each sample. The results are given in Table I and Figures 1 and 2. To obtain the vapor pressure, representative mixtures were made up and boiled with efficient reflux at four different pressures (4). This was done first on pure tetrachloroethylene, and a sample waa withdrawn to check the compositionby refractive index. Then small amounts of carbon tetrachloride were added 1
Present address. Mine Safety Appliances Company. Pittsburgh, Pa.
70
o
0.1 0.2
rn
0.t as 0.6 0.7 Nccl+ IN CC12:CC12
0.8 0.9
Figure 1. Liquid-Vapor Composition Diagram for Carbon TetrachlorideTetrachloroethylene
1.0
I
Vol. 36, No. 12
INDUSTRIAL AND ENGINEERING CHEMISTRY
1176
apparatus and experimental technique used in obtaining the vapor pressures were tested by determining the boiling point of carbon tetrachloride a t several different pressures. The vapor pressure values so obtained checked the best values reported in the literature within about 0.3% and were reproducible. The accuracy of the temperature-pressure data was limited, not by the pressure measurement, which could be measured to a greater degree of accuracy than required, but by the temperature measurement which was read to somewhat better than 0.1 O C. The boiling point temperatures were plotted against the presewe; from the smooth curves the vapor pressures a t 60°, 65", 70°, and 75' C. over the whole mole fraction range were obtained as
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 / . O
N
CC&:CCI, Figure 3.
Ncct,
in
\iquid
Figure 2. X - Y Diagram for Carbon Tetrachloride-Tetrachloroethylene
ACKNOWLEDGMENT
TABLE I. ANALYSISOF DISTILLATE CCla in Liquid Mole fraction Wt. % 0.000 0.000 9.344 0.100 0.200 18.825 0.300 28.447 38.212 0.400 48.123 0.500 58.184 0.600 68.399 0.700 78.771 0.800 89.303 0.900 1.000 100.000
B.P. a t 760 Mm., C. 120.8 108.6 100.8 93.0 89.3 86.0 83.5 81.5 79.9 77.5 76.9
Mole Fraction CCh in Vapor 0.000 0.469 0.670 0.800 0.861 0.881 0.918 0.930 0 958 0 980 1,000 I
I
TABLE 11. 1 Boiling Temp., C. 109.5 103.3 78.5 71.5 120.8" 60.0"
108.0 102.0 81.5 66.0
114.0 60.0
2 Pressure, Mm. Hg 589.7 475.1 213.5 159.0 760.0" 87.0" 621.0 510,l 265.2 152.3 760.0 115.0
3
4
Wt. % CCh 0.0
Wt. % CaClr 100.0
.. .. .... ..
5.0
.. ..
.. .... 14.2 .. .. .. ....
.. .. .,
.. .. 95.0
..
..
..
....
The authors wish to acknowledge the aid given by Gene Pillar in obtaining a portion of the laboratory data. LITERATURE CITED
(1) McDonald, H.J., J . Phys. Chem., 45,706 (1941). (2) McDonald, H.J., and McMillan, W. R., Chemist-Analyst, 32,
--
6Q (1948). ,-1--
(3) McMillan,'W. .R.,and McDonald, H. J., IND.ENQ. CHEm., ANAL.ED.,15, 114 (1943). (4) MoMillsn, X. R.,and McDonald, H. J.,J . Phys. Chem. (in press).
TEMPERATURE-PRESSURE
DATA
5 Boilins Temp., C. 76.8 75.8 71.5 58.0 76.9" 60.0'
6 Pressure Mm. H i 749.4 719.6 634.3 395.2 760.0" 415.0"
7 Wt. % CClr 100.0
.. .. .. .. ..
0.0
82.0 79.2 72.2
749.6 684.2 541.3 368.6 760,O 358.6
81.0
..
19.0
.. .. ..
.. .... 40.1 .. .. .. .. ..
60.0
82.5 60.0
Vapor Pressure of System at
Four Temperatures
shown in Figlire 3. The curves were extrapolated graphically to intersect the line representing 760.0 mm. pressure so as t o give values of the boiling points of the system under normal atrnospheric pressure. I n the graphical extrapolation, the accuracy must necessarily have been reduced somewhat, from 0.3 to about 0.4%. The vapor pressure curves in Figure 3 show slight deviations from the values predicted by Raoult's law.
1.0
0.5
0
..
8 Wt. % C&lr
.. .. .. .. ..
..
I
....
..
..
.. .. ..
10 Pressure, Mm. Hg
11 Wt. % CClr
12 Wt. % c2c1,
96.0 91.2 83.3 70.0 95.4" 60.0"
749.3 673.4 531.5 330.0 760.0" 222.O a
44.1
.. .. .... ..
55.9
98.0 94.0 80.8 68.5 98.3 60.0
748.9 645.1 439.7 292.0 760.0 207.0
35.3
64.7
9 Boilingc. Temp.,
.
59.9 88.5 794.4 743.4 85.8 668.8 85.0 666.3 441.4 .. 72.0 241.3 265.6 57.0 .. 164.9 89.0 760.0 760.0 .. 60.0 298.0 142.0 60.0 0 The second to the last of each group of a i s values of temperature and pressure was obtained b y extrapolation four experimentally determined points. The last value (60.0° C.) was read from the smooth curve. 108.0 99.6 72.5 63.0 108.7
CCIC
... . .. *.
101.0 748.8 25.2 74.8 98.6 683.4 79.5 370.6 '. . 64.5 225.3 760,O 101.5 .. .. 180.0 60.0 of the smooth curve drawn through the first
.. .. .. I
.
.. .. ..
