INDUSTRIAL AND ENGINEERING CHEMISTRY
1144
LITERATURE CITED
(1) Abraham, H., “Asphalts and Allied Substances”, 4th ed., p. 1011 (1938). (2) Asahara, G . , Sci. Papera Inat. Phy8. Chem. Resmrch (Tokyo), 1, 23 (1922); Japan. J. Chetn., 1, 35 (1922). (3) Biaatoch, K.,and Hofmann, U., Angew. Cham., 53,327(1940). (4) Bolton, K.,Cullingwortb, J. E., Ghosh, B. P., and Cobb, J. W., J. Chem. SOC.,262 (1942). (6) Debye, P., and Scherrer, P., Physik. Z . , 18,291 (1917). (6) Dennstedt, M.. “Anleitung zur vereinfachten Elementaranalyae”, 4th ed., p. 68 (1919); Houben, J., “Die Methoden der organischen Chemie”, Vol. 1, p. 109 (1925). (7) Gibson, J., and Riley, H. L., Fuel, 21,36 (1942). (8) Hofmann, U.,Bsr.. 65B,1821 (1932). (9) Hofmann, U.,Groll. E., and Lemcke, W., 2. angsw. Cham., 44, 841 (1931). (10) Hofmann, U.,and Lemcke, W., 2. anorg. aZZgem. C h m . , 208, 194 (1932). (11) Hofmann, U.,Ragoss, A., and Sinkel, F., KollOid-Z., 96, 231 (1941). (12) Hofmann, U.,and Wilm, D., 2.Etedrochem., 42,604 (1936). (13) Hofmann, U.,and Wilm, D., Z . physik. Chem., B18, 401 (1932).
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Vol. 36, No. 12
(14) Koch-Holm, E., Wiss. Vw65ent. Sinens-Konsan, 6,188(1927). (16) KohlachUtter, V., 2. anorg. Cham., 105,36 (1919). (16) Lowry, H. H.,J . Am. Chem. Soc., 46,824 (1924). (17) Lowry, H. H., J. Phur. Cham., 33, 1332 (1929). (18) Lowry, H. H., Landau, H. G., and Naugle, L. L., Trona. A m . Inat. Mining Met. Bngro., 149,297 (1942). (19) Marcusaon, J., 2. angsw. Chem., 29, 346 (1916). (20) Mekler, L. A., Fuel8 and Furnaces, 5 (1927). (21) Miwa, M.;Science Repts. Tdhoku I m p . Unio., 23, 242 (1934). (22) Morrell, J. C., and Egloff, Gustav, Chemistry & Industry. 51. 467 (1932); Univcrsd Oil Produdo Booklet 111. (23) Nellensteyn, F.J., Proc. World Petroleum Congr., 2, 618 (1933). (24) Riley, H. L., Chemistry & Induotry, 58,391 (19391. (25) Sakanov, A. N., and Vssil’ev, N. A,, Gosudartawennae Nauch.Tekh. Iadotelstvo Moscow-Petrograd, 1931, 265; Chem. AbSh‘oC&, 28, 298 (1934). (26) Stroud, W. F.. in “Science of Petroleum”, Vol. 4, p. 2772, London, Oxford Univ. Preas, 1938. (27) Tilirheyev, M. D.,J. Applied Chsm. (U.S.S.R.), 12, 1402 (1939); Chem. Abskada, 35, 2699 (1941). (28) Warren, B. E.,J. Cham. Phys., 2, 561 (1934). (29) White, A. H., and Oermer, L. H., Zbid., 9,492 (1941).
VAPOR-LIQUID EQUILIBRIUM CONSTANTS FOR
Benzene,
50
20
Toluene, and
10
Methyl-
I
d
2
cvclohexane d
I
V
0.5
APOR-liquid equilibrium constants may be defined by the equation :
K = ylz 0.2
where y = mole fraction of a component in vapor phase mole fraction of a component in liquid phase 2 From the fugacity rule of Lewis and Randall (6) for ideal solutions:
0.1
XfL = YfV 0.05
where fL = fugacity of pure component in liquid phase at temperature and pressure of system fv = fugacity of pure component in vapor phase at temperature and pressure of system
0.02
PRESSURE QOI
POUNOS PER 10
20
SQUARE
INCH
50
Figure I
ABSOLUTE IW
200
600
The fugacity of the vapor is available when the reduced temperature and pressure are known. The fugacity of a pure component in the liquid phase is equal to its fugacity in the vapor phase when the total pressure of the system equals the vapor pressure of the pure component at the
114s I
INDUSTRIAL A N 9 ENGINEERING CHEMISTRY
December, 1944
c
I
0.5
0.2
0.1
O M
0.02
'
0.01
10
4
20
?a
loo
200
600
"."I
4
10
50
loo
200
Figure 2
Figure 3
temperature of the system. When the total pressure of the sy5 tem is different from the vapor pressure of the pure component, the fugacity of the liquid may be obtained from the following equation :
The vapor pressures and critical constants used for benzene and toluene were those ordinarily available (9, 7); the vapor pressures and critical constants for methylcyclohexane were obtained from unpublished data (I, 4 ) )and the fugacity data of Lewis and Luke (6) were checked and extended to lower reduced temperature from P-V-T data in International Critical Tables (9). These charts are rigorously applicable only where the solutions involved attain the characteristics of ideal solutions-Le., a solution of aromatics in aromatics or of naphthenes in naphthenes. It is believed by the authors, however, that frequently these data will be helpful in calculations involving solutions which vary somewhat from the ideal, especially in the correlation of future data on nonideal solutions. For instance, with suitable experimental data, a correlation of ratio of actual to ideal K for aromatics vs. per cent paraffins in the aromatic solution might be developed. Other similar correlations could be obtained for various other nonideal solutions.
where f~ = fugaoity of ure component at temperature of system a n B vapor pressure of component correspondin to this temperature fb = fugacity pure component in li uid phase a t system total pressure and temperature Pp = vapor pressure of pure component a t temperature of system PL = total pressure of system R = as constant in consistent units V = 8quid molal volume, cu. ft./lb. mole T absolute temperature of system
05
07
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HARRY G. DRICKAMER Pan American Refining Corporation, Texos City, Texas
JOHN R. BRADFORD Texos Technological College, Lubbock, Texos A t present serving a8 Ensign, U,B.N.R.
LITERATURE CITED
(1) Andres, D., Ph.D. dissertation, Univ. of Texas, 1942. (2) International Critical Tables, Vol. 111, pp. 221-7, New York, McGraw-Hill Book Co., 1928. (3) IbM., Vol. 111, pp. 244-7. (4) Kasch, J. E., private communication, 1942. (6) Lewis, G . N., and Randall, Merle, "Thermodynamics", New York, McGraw:Hill Book Co., 1923. (6) Lewis. W. K.,and Luke, C. D., IND.ENG.C m m . ,25, 726 (1933). (7) Perry, J. H., C h a i c d Engineers' Handbook, pp. 377-88,Znd ed., New York, McGraw-Hill Book Co., 1941,
