-
J. Chem. Eng. Data 1981, 26, 47-51
9
o'6 0.4
30
40
50
60
70
quoted accuracy of the measurements. Acknowledgment We express our thanks to Mr. Roger Paul for maintaining the experimental installation. Literature Cited
n
20
47
80
T E M P E R A T U R E T/'C
Figure 4. Deviation of the viscosity measurements of ref 73from the calculated values via eq 10-14: (0)c = 0.3330 m; (0) c = 0.2356 m; (A)c = 0.4712 m. The coefficients 4, and gY which appear in eq 11 and 13, respectively, were calculated from the measurements presented earlier. The resulting Coefficients are seen listed in Tables XI11 and XIV for Na2S04solutions and Tables XV and XVI for K2SO4 solutions, respectively. Figures 2 and 3 depict the deviations of the experimental results from the correlations for Na2S0, and K2SO4, respectively. The correlations reproduce the experimental results with a maximum deviation of 0.9% for Na2S04solutions and 0.7% for K2SO4 solutions. The standard deviation is 0.4% for the Na2S04as well as the K2SO4 solutions, which is well within the estimated accuracy of the experimental data. The only measurements of viscosity available for comparison are those by Korosi and Fabuss ( 13) for aqueous Na2S04solutions. Figure 4 depicts the deviation of these measurements from the correlations presented here. The deviations are within f0.5 % with a standard deviation of 0.26%, which is within the
-
(1) Conela. R. J.: Kestin. J.: Khalifa. H. E. Ber. Bunsenaes. phvs. Chem. 1070, 83, 20. (2) Conela, R. J.; Kestln J.; Khalifa. H. E. J . Chem. Eng. Data, In press. (3) Qrhnes, C. E.; Kestln, J.; Khallfa, H. E. J . Chem. Eng. h t a 1070, 24, 121.
(4) Kistln, J.; Khallfa, H. E. Appl. S d . Res. 1076, 32, 483. (5) Keii, (3. S.; Whailey, E. J. Chem. Phys. 1075, 62, 3496. (6) Kestln, J.; Khalifa, H. E.; Abe, Y.; Grimes, C. E.; Sookiazlan, H.; Wakeham, W. A. J. Chem. Eng. Data 1078, 23. 328. (7) Kestln, J.; Khalifa, H. E.; Ro, S. T.; Wakeham, W. A. J . Chem. Eng. mte 1077, 22,207. (8) Kestln, J.; Khallfa, H. E.; Sodtlazlan, H.; Wakeham. W. A. Ber. Bunsenges. phys. Chem. 1076, 82, 180. (9) Kestin, J.; Leldenfrost, W.; Liu, C. V. 2. Angew. Math. Phys. 1950, 10, 558. (10) Kestin, J.; Moszynski, J. R. Trans. ASME 1056, 80, 1009. (11) Kestin, J.; Sokobv, M.; Wakeham, W. A. J . Phys. Chem. Ref. Data 1076, 7. 941. (12) Kestin, J.; Wang, H. E. J . Appl. Mech. 1057, 79, 197. (13) Korosi, B. M.; Fabuss, A. J. Chem. Eng. Date 1068, 13, 548. (14) Potter, R. W., II; Brown, D. L. Geol. Surv. Open-File Rep. (U.S.), No. 76-255, 1976. (15) Potter, R. W. 11; Brown, D. L. Gee/. Surv. Open-Flk, Rep. (U.S.),No. 76-501, 1976. (16) Potter, R. W., 11; Shaw, D. K.; Haas, J. L., Jr. Geol. Surv. Bull. ( U S . ) 1075, No. 1417. Received for revlew May 19, 1980. Accepted July 30, 1960. Financlai support was provlded by the U.S. Geological Survey (&ant 14-0&00016342). One of the authors, R. J. Correla, was also in recelpt of a National Sclence Foundation Oladuate Tralneeshlp made avallable through Brown University.
Solubility of Solids in Supercritical Carbon Dioxide and Ethylene Ronald T. Kurnlk, Samuel J. Holla, and Robert C. Reid"
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02 139
Solubillty data were obtalned for five different sollds in both supercritical carbon dioxlde and supercritlcal ethylene. A one-pass flow system was used to measure the equillbrlum solubilities. The range in temperatures covered was 308-338 K and the range In pressures was roughly 80-280 bar. Over the past few years, significant interest has been expressed in a separation concept wherein a condensed phase (liquid OT soli) is contacted with a fluid phase that is supercritical both in the temperature and pressure sense. An often-quoted example is the German patent to remove, selectively, caffeine from green coffee beans by using supercritical carbon dioxide (24). Other examples would include deasphatting heavy residual oils with supercritical propane ( 7 9 ) and removing adsorbed materials from activated carbon with supercrkical carbon dloxide (8, 9 ) . Supercritical water has been explored as a solvent medium to carry out chemical reactions or biological degradations without char formation ( 1 , 7). In all of these instances, the dissolution effect appears to be related primarily to the nonideali of the supercritical fluid phase which leads to solvent behavior more representative of a llquid phase-at temperatures above what could have been attained if only a liquid had been used. Also, because of the high density of the supercritical solvent, process volumes are reduced (but 0021-9568/81/1726-0047$01 .OO/O
Table I. References with Solubility of Solids in Supercritical Fluids solid hexachloroethane naphthalene hexachloroethane and naphthalene quartz quartz naphthalene naphthalene naphthalene phenanthrene phenanthrene phenanthrene phenanthrene diphenylamine
solvent
T, K
ethylene ethylene ethylene
289.5-296.5 289.5-296.5 289.5-296.5
water water ethylene carbon dioxide ethylene ethylene ethane carbon dioxide methane carbon dioxide
653-698 423-873 285-318 308-328 285-308 313 313 31 3 313 305-310
P,bar
ref
1-170 1-170 1-170
22 22 22
300-500 1-1000 50-300 60-330 40-100 138-551 138-551 138-551 138-551 50-225
23 5
20 20 3 4 4 4 4
21
the high pressure increases equipment costs) and transport properties are intermediate in value between those of a gas and a liquid; Le., diffusion coefficients are much higher than for typical liquids. In view of the interest expressed in this technology, it is surprising that so few data exist to illustrate quantitatively the solvent effect. In Table I, we summarize those references known to us that provide equilibrium solubility data. Not shown in this table are a number of other references which relate only 0 1981 American Chemical Society
48 Journal of Chemical and Engineering Data, Vol. 26, No. 1, 1981
to the pressure-temperature behavior of high-pressure systems wherein a solid (or liquid) phase is in equilibrium with a gas (fluid). Knowing the P- T behavior of a binary system is, however, very necessary as only those systems with critical end points are viable for supercritical extraction. Rowlinson ( 76) discusses this problem, and Modeli et al. ( 70)have estimated the critical end points for the systems carbon dioxide-naphthalene and ethylene-naphthalene by using an equatkm-of-state approach. Normally, however, if the condensed phase is solid and has a melting polnt significantly above the critical point of the solvent, then supercritical extractin is a suitebb method for separation. In this paper we present new experimental equilibrium solubilities for five solid systems by using both supercritical carbon dioxide and ethylene. It is also shown that these data may be well correlated by using thermodynamic relationships and an equation of state.
Table 11. Solid Properties
solid
K
T, K
2,3-dimethy 1naphthalene
376
2,6-dime t hylnaphthalene
382
phenanthrene
314
benzoic acid
396
hexachloroethane
460
308 318 328 308 318 328 318 328 338 318 328 338 308 318 328
vapor vapor press., press., Pa ref 1.21 3.49 9.01 1.22 3.45 9.13 0.155 0.423 1.09 0.780 2.16 5.62 154 284 504
supplier, purity
11
Aldrich, 99%
11
Aldrich, 99%
2
Eastman Kodak, 98%
2
Aldrich, 99%
17
Aldrich, 99%
a At 1 bar.
Thermodynamic Relatlonshlps The thermodynamics applicable to relate the equilibrium mole fraction of a solute dissolved in a high-pressure gas (fluid) have been treated earlier by Prausnitz ( 73, 74). The results may be written in a deceptively simple form. With 1 representing the solute which both is present as a pure solid and is dissolved in the fluid phase
with y1 the fluid-phase mole fraction of 1. In eq 1 it has been assumed that: (a) the fluid-phase component does not dissolve in the solid, (b) the molar volume of the solid is independent of pressure, and (c) the fugacity coefficient of pure vapor 1 at T and P, is unity. In most instances, these three assumptions are appropriate. The only term on the right-hand side of eq 1 which reflects the fact that the fluid phase is a mixture is the fugacity coefficient of component 1, $ Accurate estimates of this variable are necessary to determine y,. 4 , can be found from an applicable mixture equation of state using well-known thermodynamics (6). We have employed both the Soave ( 78) and the Peng-Robinson ( 72) modifications of the Redlich-Kwong equation of state ( 75). Both provide equally good estimates of 4 . Only the Peng-Robinson form is illustrated here.
,.
mPnt KRY -
T c
T05'
Ir*o+*r
FC
TOmPQroturo ;onlrollcr D - O S S U ~ Q
CSl, -3lIQr
U
Tubes
73.0 m 0 1 Q r
F
PTQiS"T@
GOJQR ThorroC3upI@
Equipment
Flow - C h a r t
Figure 1. Equipment flow chart.
Mixing parameters a and b are related to the pure component terms a, and bi by eq 7 and 8. Variables A and Bas used in
a = CXx,x,a,1'2a,1/2(l- k,,) /
I
(7)
bl
"I
n1
[ai(T)ai( a(T)
vi-;
"}
eq 2 and 3 are defined by eq 9 and 10.
Z + 2.4148 In (Z- 0.414,)
(2)
In this equation Zis the compressibility factor of the gas mlxture and is found from the original equation of state Z3 - (1 - 8)Z24- ( A
- 3B2 - 2B)Z- (AB- B2 - B3) = 0 (3)
To calculate 4 , or Z,pure component parameters a, and b, are found from eq 4 and 6 using critical properties and acentric factors. ai =
R~ T ~ , ~ [1 K / ( 1 PCI
a,----
+
- Tr11'2)]2
(4)
where K,
= 0.37464
+ 1 . 5 4 2 2 6 ~- ~0 . 2 6 9 9 2 ~ ~ ~
b/ =
QLJTCJPC,
(5)
(6)
The interaction
A = af/(R2T2)
(9)
B = bP/(RT)
(10)
parameter k,,is characteristic of a binary pair (iand j ) and is normally assumed to be independent of pressure, composltbn, or temperature. As will be seen later, however, we did find a weak temperature effect on kt for very nonideal fluM mixtures at high pressures. Experlmental Section The solubilities of four relatively nonvolatile solkls (2,3dC methylnaphthalene, 2,6dimethylnaphthalene, phenanthrene, and benzoic acid) were measured in both supercritical carbon dioxide and ethylene. In addition, hexachloroethane solubllfty was determined in supercritical carbon dioxkie. In Tabb I1 we list the important physical properties of these pure solkls. Temperatures ranged from 308 to 338 K and pressures from -80 to 280 bar. Experimental data were obtained with the flow system shown schematically in Figure 1. The feed gas (carbon dioxkle or
Journal of Chemhl and Engineering Data, Vol. 26, No. 1, 1981 48 Table 111. Comparison of Test Data with Those of Tsekhanskaya (20) for C0,-Naphthalene at 328 K 1O2(molfraction of naphthalene)
system run mass of press., time, 103(volume naphthalene -bar min of CO,),a m3 collected, g this work Tsekhanskaya 125 162 197 253
20 10 10 8
10.00 5.00 5.00 4.00
0.75 0.79 1.10 1.06
1.40 2.92 4.01 4.79
1.42 3.00 3.99 4.85
a The pressure at the dry-test meter was 1.01 1 bar, and the temperature 295.4 K (except for the 253-bar test when it was 294.8 K).
ethylene) was compressed to the system pressure with an AMINCO single-stage compressor. Pressure fluctuations were dampened with an on-line surge tank fitted with a pressure controller at the outlet. Pressures were easily controlled to f 1 bar. The high-pressure fluid, at ambient temperature, was allowed to flow into a vertical extraction tube 1.8 cm in diameter and 30 cm long. By virtue of a low fluid flow rate, caiculatlons and experimental temperature traverses showed that the fluid very rapidly attained the temperature in the extraction tube. The extraction tube was packed with alternate layers of the test sold and quartz wool. It was wrapped with heating tape, and the temperature monitored with a thermocouple placed in the center of the tube. The vessel temperature could be controlled to f0.5 K. Pressures in the extraction tube were measured with a calibrated Heise gauge mounted at the inlet. The pressure drop across the bed was negligible. The supercritical extractant with dissolved solid passed from the extractor into a heated regulating valve and was subsequently expanded to 1 bar. The dissolved solids precipitated in a U-hrbe (at room temperature) following the valve. A second U-tube in the train was employed to insure trapping of all of the solid. Both tubes were packed with quartz wool at the outlet. In all cases over 99% of the solid was always trapped in the first U-tube. The solutafree, low-pressure extractantgas flow was measured by a rotameter (to insure steady flow) and by a calibrated Singer dry-test meter-at which point the stream temperature and pressure were also measured. As the U-tubes were initially tared, the mass of precipitated solid was found by weighing the tubes after an experiment on a Mettler balance accurate to f5 mg. With this value and the total extractant flow from the dry-test meter, the concentration of the solids in the supercritical fluid was readily determined. (In all cases, the amount of solute in the gas leaving the dry test meter was negligible.) A number of experiments were conducted to insure that the technique would provide accurate and reliable equilibrium solubilities. The most important proof test was to run with the system naphthalene-carbon dioxide so as to compare the measured values of naphthalene solubility with those of Tsekhanskaya (20). In Table 111 we show the resuits for four runs at 328 K. When the equilibrium solubilities are compared with Tsekhanskaya’s data, the average deviation is only 1.3%. We also carried out tests for long times but separated the run into several periods. At the start of each period, new (tared) U-tubes were inserted and the previous tubes removed. No change in equilibrium concentration was noted when data from the different time periods were compared. We also carried out repeat tests (for naphthalene-CO,) in which we varied the position of the solid in the extractor; i.e., data were obtained with the solid distributed evenly in layers over the entire helght (the usual mode), with the solid only in the lower half, and with solid only in the top half. Identical results were obtained for ail tests at the same temperature and pressure. These resuits indicated that the extractor was Iso-
Table IV. COZ-S6-DimethylnaphthaleneData
T = 308 K (jClZ=
P, 97 145 195 245 280
(k,,= 0.0989)
P,
bar 1.90 2.96 3.83 4.01 4.47
T = 328 K @,,= 0.100)
T = 318 K
0.101)
Y
bar
x 10-3
98 146 194 244 280
X X X X
P, Y 7.57 3.94 5.09 6.27 6.77
bar
x 1 0 - ~ 96 146 195 246 280
X X X X
Y
x 10-4
3.05 4.31 6.15 7.99 9.21
X X X
lo-’ lov3
X
Table V. CO2-2,3-DimethylnaphthaleneData
T = 308 K (k = 0.0996)
P, bar 99 143 194 242 280
Y 2.20 x 104.40 X 5.41 X 5.82 X lo-’ 6.43 X
T = 318 K (k,,= 0.102) p, bar 99 145 195 242 280
T = 328 K
(k,,= 0.106)
P, 1.28 4.79 6.37 6.88 7.19
Y
bar
x 10-3
99 146 197 241 280
X X X
lo-’
X
Y
x 10-4
3.40 4.45 7.14 8.47 9.01
X lOV X X X
Table VI. C,H4-2,6-Dimethyhaphthalene Data
T = 308 K (klz= 0.0225)
P, bar 80 120 159 200 240 280
T = 318 K (klz= 0.0200)
P, Y 4.83 2.35 4.61 6.95 9.27 1.09
X
x 10-3 X X
X X
lo-’
bar 78 120 160 200 240 280
T = 328 K ( k l Z =0.0166)
P, Y 1.88 X 2.19 x 5.56 X 9.08 X 1.38 X 1.71 X
bar 78 1 0 - ~ 120 160 200 lo-’ 240 lo-, 280
Y 2.36 2.20 6.74 1.30 2.00 2.75
X
x 10-3 X X X X
lo-’ lo-, lo-’
Table VII. C2H,-2,3-Dimethylnaphthalene Data
T = 308 K (k12= 0.0246) p, bar Y77 3.13 X 120 2.58 x 10-3 159 6.02 X 200 9.65 X lo-’ 240 1.26 X lo-, 280 1.50 X lo-’
T = 318 K (k,,= 0.0208)
P,
T = 328 K ( l ~= ,0.0147) ~
P,
bar
Y
bar
80 120 160 200 240 280
3.66 X 2.58 x 10-3 7.18 X 1.21 X lo-, 1.83 X lo-, 2.41 X lo-’
80 122 160 200 240 280
Y 3.00 3.17 8.78 1.89 3.21 5.24
X
x 10-3 X X X X
lo-’ lo-’ lo-, lo-,
Table VIII. C0,-Phenanthrene Data T = 318 K ( k , , = 0.113) p, bar 120 160 200 240 280
Y 8.49 1.40 1.70 2.23 2.28
x 10-4 X
loF3
x 10-3 X X
lo-’ lo-’
T = 328 K ( k l Z= 0.108) p, bar 120 160 200 240 280
Y 4 . 6 5 ~10-4 1.51X 2 . 1 4 ~10-3 2.79X 3.19X
T = 338 K ( k l z = 0.106) p, bar 120 160 200 240 280
Y 3.28 1.18 2.37 3.28 3.84
x 10-4 X
lo-’
x 10-3 X X
lo-’ lo-’
thermal and, also, that equilibrium was rapidly attained. Tests were also run in which the flow rates was varied from 0.036to 0.13 standard m3/h. No effect was noted in the outlet concentration of naphthalene, and this reinforces our conclusbn that equilibrium was rapidly achieved.
Results and Dlscwslon The equiilbrium solubilities found In this work are shown In Tables IV-XII. In addition to noting the mole fraction of the solutes in the supercritical fluid, we also show the solute-solvent Interaction parameter determined from the data and the PengRobinson equation of state.
50 Journal of Chemical and Engineering Data, Vol. 26, No. 1, 1981
Table X C0,-Benzoic Acid Data
Table IX. C,H4-Phenanthrene Data
T = 328 K ( k , , = 0.0355)
T = 318 K ( k , , = 0.0459)
p, bar 120 160 200 240 280
Y 8.16 x 10-4 1.74 X lo-’ 2.67 x 10-3 3.70 X lo-’ 4.56 X lo-’
p, bar 120 160 200 240 280
Y 7.38 x 1.76 X 3.33 x 5.34 X 8.29 X
T = 338 K ( k , , = 0.0318)
p, bar 10-4 120 lo-’ 160 10-3 200 lo-’ 240 loe3 280
T = 318 K ( k l z = 0.00994)
T = 328 K (k,,=-0.00172)
P,
P, bar
Y 7.43 x 1.84 X 3.64 x 6.38 X 1.06 X
io-4
io-’ lo-’ lo-’
120 160 200 240 280
T = 338 K (k,,=-0.0124)
P,
Y
bar
Y
1.14 X 2.37 X 3.18 x 4.21 X 4.38 X
120 160 200 240 280
4.90 X 2.27 X lo-’ 3.86 x 10-3 5.16 X 7.34 X
loe3 10-3 lo-’ lo-’
Y 3.20 X 1.72 X 4.10 x io-’ 6.95 X 9.83 X lo-’
bar 120 160 200 240 280
Table XI. C,H,-Benzoic Acid Data T = 318 K ( k , , = -0.0562)
T = 328 K (k,,=-0.0641)
P,
P, bar 120 160 200 240 280
10-2
I
I
1 0 ‘ ~-
5.76 x 1.35 X 1.90 x 2.90 X 2.91 X
p, Y bar 5 . 4 8 ~10-4 120 1.60 X 160 2.61 x 10-3 200 3.61 X 240 4.08 X 280
bar
Y
120 160 200 240 280
10-4 10-3 1O-j lo-’
T = 338 K (k1,=-0.0755) Y 5.43 x 10-4 1.92 X 3.50 x io-’ 4.93 X 6.18 X lo-’
Table XII. C0,-Hexachloroethane Data
10-4r-
SYSTEM CpH4-2.3 DMN - P R EOUATION OF STATE
I
I 1
328
T = 308 K (k,,=0.129) p, bar
Y
99 149 199 248 280
1.45 X 1.86 X 1.96 X lo-, 1.99 X lo-’ 1.80 X lo-’
Io-‘ o
40
eo
120
160
200
T = 318 K ( k , , = 0.123)
I
P,
p, bar 100 148 198 247 280 I
I
T = 328 K ( k , , = 0.116)
Y lo-, lo-’ lo-’ lo-’ lo-,
1.03 X 2.39 X 2.60 X 2.78 X 2.70 X I
I
I
l
I
Y 3.79 X 2.32 X 3.89 X 3.93 X 3.89 X
bar 97 145 195 245 280 I
l
/
l
lo-’ lo-’ lo-* lo-’
/
zeo
240
PRESSURE ( B A R S )
Flgure 2. SolublHty of 2,3dlmethylnaphthlene in ethylene.
lo-2
Io 328 K,
I
-~
I SYSTEM. BENZOIC ACID-COP -PR EOUATION OF STATE -
g
, ,
4
u 2 W
m
IO-^
R. N
SYSTEM: C o p - 2 . 3 DMN - P R EOUATION OF’ STATE
10-6 IDEAL GAS
IO-’ 3I8K
\ 10-8
PRESSURE ( B A R S )
Flgure 3.
Solubillty of 2,3dlmethyinaphthalne in carbon dloxlde.
The data for the 2,3dimethylnaphthalene test systems are shown in Figures 2 and 3. At comparable temperatures and pressures, ethylene “ a # Y Is a much better solvent than COP, but, when comparisons are made at the same reduced con-
I
1
40
l
l
l
l
,
l
l
I
120 160 zoo PRESSURE ( E A R S )
eo
1
1
240
I
i IO
Flgw 4. Solublllty of benzolc acid in carbon dbxlde (mole fractbns are uncorrected for dlmerlzatbn).
ditions, then COPis a more efficacious solvent. The solld curves in Figures 2 and 3 represent the prediction of the equilibrium solubilii using eq 1 and the interaction pa-
J. Chem. Eng. Date 1981, 26, 51-53
rameters in Tables V and VII. These kr values were found by using a nonlinear least-squares regression technique to give the best fit between theory and experiment. In Figure 4, the experimental benzoic acid mole fractions in supercritical carbon dioxide are shown as a function of temperature and pressure. These data are also well cowrelated with the Peng-Robinsm equation of state. Also shown in this figure are the calculated benzoic acid concentrations for cases where the vapor phase is assumed to behave as an ideal gas. The ideal-gas assumption (4 of eq 1 is unity) is valid only at very low pressures. At high pressures, an idealgas assumption grossly underestimates the actual concentration. Acknowledgment
We thank the Computer Center, Massachusetts Institute of Technology, for the use of its facilities. variables in Peng-Robinson equation of state Peng-Robinson binary interaction parameter pressure, bar vapor pressure, bar gas constant temperature, K moiar volume, cmg/mol fluid-phase mole fraction compressibility factor
Greek Letters K
4 w
a,, fib
parameter in Peng-Robinson equation of state fugacity coefficient acentric factor constants in Peng-Robinson equation of state
C
r
51
critical property reduced property
Literature Cited Amln, S.; Re#, R. C.; Modell, M., paper presented at the Intemocbty Carference on Environmental Systems, San Francisco, 1975. de Krun, C. Q.; van -4, C. H. D.; Voogd, J., prosanted at the Quatrbm Conference Interactlonabde Thermodynemlque wmlque, 26 au 30, Montpok, France, 1975. Dlepen, Q. A. M.; Sctmffer, F. E. C. J. Am. chsm. Soc. 1948, 70, 4085. Elsenbetss, J. San Antonb, TX, Aug 1964, Southwest Research Ins& Me Fkurl Report Contrect NO. DA lSlO&AMC244(A). Jones, D.; S t a h , R., Ed. “Hlgh Tamperatwe HI@ Pressure Eiectm c4wnMw In Aauoow solutkns”:Natbnal Sock& of Corrosbn EnaC necws, 1973 p i31. Moddl, M.; Reld, R. C. “Thermodynemlcs and h A p p k a W ; PrentiCe Hall: EndeWood c”S, KI, 1974; Chapter 8. Modell. M., paper presented at the Intersddsty Conference on En& roMnental Systems,Sen Francbco, 1977. Moddl, M.; Robey, R.; Knkonk, V.; deFMippl, R.; oeatrdch,D., paper presented at the 87th Natbnal Meeting, AICM, Boston, 1979. Moddl, M.; M#iPpl, R.; Knkonls, V.. paper presented at the ACS meeting, “ I , Sapt 1978. Modell, M.; Hang, G.; Helba, A., paper presented at the 72nd Annual MeetIfg, AI=, Nov 1979. Osbom, A. Q.; Dwelln, D. R. J. chsm. €ng. Deta 1976, 20, 229. Pan& D. Y.; Robhson, D. B. Ind. €w. Chem. Fun&“ 1976, 75,59. Raugnlk, J. M. NBS Tech. Note (U.S.) 1 8 8 , 378. ReuenitZ,J. M. “ M o b c h Thermodynemlcs of Fluid Phase Equilibria"; PmtksHaW: Enplewood C”S, NJ, 196% Chapter 5. Redllch, 0.;Kwong, J. N. S. Chem. Rev. 1849, 44, 233. Rowllnson, J. S. “Llqulds and Uquld Mixtures”,2nd ed.; Buttcworths: London, 1969. Sax, N. I.“Dangerous PropwtIes of Industrial Matsrlels”,5th ed.;Van NostranbRewldd: Princeton, KI, 1979; p 718. Soeve, Ci. Chem. €ng. Sei. 1972, 27, 1197. sokmon, H. J., pew presented at the ACS W n g , Washington, D.C., Sept 1971. Tsekhanskaya, Y. V.; Iomtev, M. 8.; Mrtsklna, E. V. Zh. Flz. Khh. 1964, 38, 2166. Tsekhanskaya, Y. V.; Iomtev. M. B.; Musklna, E. V. Russ. J. plrys. Ch8m. (E@. Trenel.) 1962, 38,1177. Van W, Dksutatbn, Delft, 1950. Van Nkuwenbug, C. J.; Van Zon,P. M. Roc/. rfev. CMm. Pays-88s 1995, 51, 129. Vltzthum. 0.;H M , P. Q”an Patent 2 357 590, 1975.
-
Subscripts 1 2
Recehred for rwlew M y 19, 1980. Accepted August 7, 1980. We thank
solid component fluid component
the Natbnal scknco Foundetkn for ftnanclal support. One of us (R.T.K.) b, grateful to the Nestle Co. for Rnanclal support In the form of a felkwshlp.
Critical Mixing of Decyl Alcohol with Dipolar Liquids Helena Majgler-Baranowska Research and Development Centre of Television Engineering, Warsaw, Poland
Wlesraw Pyiuk” Deparfment of Chemistry, University of Warsaw, 02-089 Warsaw, AI. Zwirki i Wigury 707, Poland
Wojclech Jeute Research and Development Centre of Television Engineering, Warsaw, Poland
Jerzy Zloro Institote of Physics, Sikslan University, Katowice, Poland
The Ilqukl-llquld coexktence curves for critical systems of demnol with five compounds coverlng a wide range of eiectrlc permlltlvlty were detetmlned and analyzed. 0021-9588/81/17260051$01.00/0
Introduction Investlgations of precritical phenomena which occur in the vicinity of the critical solubility point in binary systems call for mixtures wlth specific properties, e.g., wlth matched indexes 0 1981 American Chemical Society
