TABLE VI. GRAPHICALLY SMOOTHED DATAI N Pressure, Lb./Sq. Inch. Abs. 100 200 300 400 500 600 637 700 800 900 1000 1500 2000 2500 3000
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60
100
130
0.0002873 O.OOO2670 0.0002679 0.0002687 0.0002696 0.0002703 0.0002706 0.0002711 0.0002717 0,0002722 0.0002728 0,0002748 0.0002760 0.0002768 0.0002775
0.0001273 0.0002045 0.0002060 0.0002076 0.0002091 0.0002106 0.0002112 0.0002122 0.0002137 0.0002152 0.0002166 0.0002221 0.0002264 0.0002287 0.0002302
0.0000876 0.0001603 0.0002003 0.0002043 0.0002075 0.0002090 0.0002108 0.0002124 0.0002145 0.0002164 0.0002182 0.0002228 0.0002276 0.0002307 0.0002355
TWO-PHASE
Temperature, O F. 160 190 205.7 Mole Fraction Propane in Water-Rich 0.0000609 0.0000698 0.0000582 0.0001303 0.0001172 0.0001197 0.0001700 0.0001782 0.0001696 0.0002132 0.0002138 0.0002107 0.0002400 0.0002210 0.0002468 0.0002680 0.0002530 0.0002261 0.0002550 0.0002271 0.0002723 0.0002295 0.0002578 0.0002767 0.0002319 0.0002815 0.0002602 0.0002623 0.0002341 0.0002846 0.0002358 0,0002865 0.0002642 0.0002415 0.0002957 0.0002715 0.0002462 0.0002783 0,0003043 0.0002507 0.0003116 0.0002835 0.0002542 0.0003160 0.0002877
inch absolute. T o preserve the clarity of Figure 7, some of the isotherms for the temperatures greater than 170” E’. have been omitted a t low pressures but are shown in Figure 8. As in the case of the solubility of water in the propane-rich phases, the solubility of propane in the water-rich phase is seen to be directly related to the volumetric behavior of the propane-
REQIOY
220 Phase 0.0000562 0.0001180 0.0001708 0.0002173 0.0002550 0.0002798 0.0002878 0.0002952 0.0003053 0.0003115 0.0003155 0.0003257 0.0003357 0.0003445 0.0003526
250
280
310
0.000513 0.0001170 0.0001768 0.0002307 0.0002767 0.0003107 0.0003222 0.0003375 0.0003562 0,0003695 0.0003787 0.0003995 0.0004144 0.0004293 0,0004442
0.0000415 0.0001160 0.0001857 0.0002480 0.0003000 0.0003453 0.0003602 0.0003828 0.0004087 0.0004287 0.0004444 0.0004927 0.0005246 0.0005502 0.0005753
0.0000220 0.0001147 0.0001923 0.0002677 0.0003277 0.0003803 0.0004007 0.0004290 0.0004627 0.0005133 0.0004886 0.0006160 0.0006858 0.0007332 0.0007703
rich phases or t o pure propane. Thus, if the compressibility o f the propane-rich phase is high, as in the behavior of a gas, the effect of pressure on the solubility of propane is high. On the other hand, a low compressibility of the propane-rich pha5e,e.g., that of a liquid,-is marked by a small effect of pressure on the solubility.
(Vapor-Liquid Equilibria f o r Binary Hyd rocarbon-Water Systems) CORRELATION OF DATA
P
ROCEDURES for correlating data are useful when they permit the prediction of the behavior of systems for which data are not available or when they may be used to extrapolate experimental data. The water contents of hydrocarbon-rich phases are correlated, whether the phase be gaseous, liquid, or in the fluid region. The hydrocarbon-rich portion of the hydrocarbon-water system may consist of a liquid phase and a gas phase, or of a single phase. The proposed correlation uses temperature and the molal volume of the hydrocarbons in the phase as variables and in this manner avoids reference to the number of phases in the system and to pressure. Several correlations have been made of the saturated water content a t high pressures of gases such as nitrogen, hydrogen, methane, ethane, and complex hydrocarbon mixtures ( I , 20, 22, 24). These methods, however, do not treat the vapor phase and the hydrocarbon-rich liquid phase as continuous phases. The simplest relation expressing the saturated water content in the vapor phase, which is generally valid a t low pressures for the nonpolar gases, is that Y = P”/P (1) where y = mole fraction of water in the vapor a t the temperature of the system p o = vapor pressure of water at the temperature of the system P = total pressure of the system Equation 1 results from the use of Dalton’s law of partial pressure and Raoult’s law, and the liquid phase is substantially pure water. Under conditions of temperature and pressure where the vapors no longer behave ideally, Equation 1 leads to serious error. Saddington and Krase ( 2 7 ) have found that a t high pressures the saturated water content of nitrogen greatly exceeds the value predicted from the application of Poynting’s relationship (18),and this has been found to be true for aqueous hydrocarbon systems ( 2 2 ) . That the relationship cannot explain the increased volatility of water with increased pressure
a t a given temperature indicates that the nonpolar gases actually have a solvent effect upon the water inolecules a t high pressures. It is evident that the same attractive and intramolecular forces come into play a t high pressures in the “solubility of a liquid in a gas” as in the solubility of a gas in a liquid. These forces are the same as those which create critical phenomena, The experimental data of the propane-water system suggr.t a correlation based upon the volumetric behavior of the hytli ocarbon-rich phases and temperature as parameters. Figuro 1 1 presents an empirical correlation in which the concentration of vater in the hydrocarbon is plotted as a function of the anhydrous molal volume of the hydrocarbon for several isotherms along lines of constant molecular weight. The correlation has been primarily developed from binary hydrocarbon-water systems, although available data on complex mixtures have been used. The molal volume is expressed here in milliliters of anhydrous hydrocarbon per gram mole of anhydrous hydrocarbon. I t is permissible to use the anhydrous molal volume rather than the actual molal volume as a correlating variable because of the low concentrations of water present in the hydrocarbon-rich phase, except a t low pressures where the solubility relationships follow Equation 1. The effect of molecular weight on the isotherms is almost nonexistent a t high molal volumes (low pressures), but becomes appreciable as the molal volumes approach those of light hydrocarbon liquids. On Figure 11, the saturated concentrations of water in methane ( 2 2 ) and in ethane ( 2 4 ) were obtained from the xork of Olds, Sage, and Lacey. The solubility of water in propane was obtained from experimental data of the authors and the threephase data of n-butane-water system from Reamer, Olds, Sage, and Lacey (25). The methane-n-butane-water data were obtained from the work of McKetta and Kat2 ( 1 9 ) . The threephase points of the last-mentioned work have been distinguished from the two-phase points on Figure 11. The data on the water content of a natural gas measured by Dodson and Standing (10)have been utilized. Additional experimental points on the
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phase region to within 10% of the actual value. The water content of the compressed lighter liquid phase well within the two-phase region can be predicted with better accuracy. The water content of saturated hydrocarbons at temperatures other than those plotted on Figure 12 may be obtained by a cross plot of log composition vs. T or 1/T, molecular weight and molal volume held constant. The use of Figure 12 presupposes a knowledge of the phase density and the phase molecular weight on an anhydrous basis under the equilibrium Conditions. McKetta and Katz (19) have shown the effect of water on the vapor-liquid equilibria relationships of the methane-n-butane system. As such data are not generally available, the phase compositions, if there should be two coexisting hydrocarbon-rich phases, should be calculated by the conventional method (33) for calculating the coexisting phases using suitable equilibrium vaporization constants for the system (2, 11, 14, 28). The vapor phase densities may be calculated by the law of corresponding states ( 3 ) . The liquid phase densities may be calculated by the method of apparent specific weights (9) or by using the partial molal volumes of condensed hydrocarbons (29). Figure 14 illustrates the homologous nature of hydrocarbonwater systems. The concentrations of water in the hydrocarbonrich phases a t the three-phase critical conditions are plotted against the three-phase critical temperatures. It is estimated that the ethane-water system contains 0.0006 mole fraction of water a t its three-phase critical conditon, which lies very near to the critical condition for pure ethane, 90" F. and 712 pounds per square inch absolute.
Figure 11. Water Content of Light Hydrocarbon Vapors and Liquids as Function of Molal Volume
solubility of water in 190 molecular weight kerosene ( I S ) and 95 molecular weight gasoline ( 5 ) appear on the correlation. The numbers opposite the methane-n-butane-water points on Figure 11 indicate the anhydrous molecular weight of the hydrocarbonrich phase. Figure 12 presents curves for even values of molecular weights up to a molecular weight of 70, based on a cross plot of Figure 11. The solubility isotherms for the propane-water system in Figure 11 at 100" and 160" F. are actually discontinuous a t the threephase conditions, where two hydrocarbon-rich phases of widely different water concentrations and molal volume coexist-that is, the section of the cmve lying between the three-phase compositions has no physical significance. Isotherms at 160"and 220"F. have been replotted for the propane-water system in Figure 13 t o illustrate this point and to show the similarity in the shape of the isotherms, although one is continuous and the other discontinuous. The water content of the saturated vapor phase of the methane-n-butane-water system is represented by Figure 12, up t o pressures very near to the three-phase critical, to within 5y0 of the total water concentration in the vapor. The saturated water content of similar hydrocarbon vapors can probably be predicted with the same degree of accuracy by this chart. The solubility of water in the three-phase hydrocarbon-rich liquid phase for the methane-n-butane-water system cannot be represented with the same degree of success. Here the maximum error, which is again to be expected in the three-phase critical region, is 20% of the total water concentration of that phase. The predicted value for this region is about 20% lower than the actual concentration. The saturated water content of the liquid phase away from the critical region can be predicted in the three-
Figure 12. Water Content of Light Hydrocarbon Vapors and Liquids as Function of Molal Volume
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where K = Henry's law constant Elimination of
7; between .
Equations 3 and 4 gives Equation 5
log% = l o g K
(P + v',2.303 RT
PO)
(5)
Defining a modified Henry's law constant, K', by Equation 6 the final form of the relationship is obtained as Equation 7. log K'
;,p log K - __
RT
-
ZP 2.303 RT
Figure 13. Continuous and Discontinuous Concentration Isotherms for Propane THERMODYNAMIC ANALYSIS OF SOLUBILITY OF PURE HYDROCARBONS IN WATER
Successful methods of calculating the solubility of slightly soluble gases in water a t high pressures from low pressure solubility data and the thermodynamic data of the pure gases a t high pressures have been developed. Krichevsky and Kasarnovsky (15) utilized the fugacity data of compressed nitrogen' and the atmospheric solubility data of nitrogen in water to compute its solubility from 25" to 100' C. up to pressures of 1000 atmospheres. The agreement of the calculated values with the experimental is excellent. They repeated the calculations using similar data on hydrogen for several isotherms from 0' to 100' C. up to 1000 atmospheres with equal success. Wiebe and Caddy ( 3 4 35) computed the solubility of carbon dioxide in water from 12" to 100' C. for pressures up to 700 atmospheres in a similar manner with fair success. An equation similar t o that used by Krichensky and Kasarnovsky is derived by starting with the rigorous thermodynamic reIationships of Equation 2.
[ ~ F . ]N$ T .= RTd where
ir',
In
5
= 62 d P
= partial molal free energy of the dissolved gas;
(7)
The units used in the calculations are: 7 2 and P in pounds per square inch absolute, Snin mole fraction, 0, in cubic feet per pound mole, and T in degrees absolute Rankine, pith I2 equal t o 10.73. When Krichevsky and Kasarnovsky (16) used Equation 7 to compute the solubilities of nitrogen and hydrogen in water, the deviations between experimental and computed solubilities were within the range of accuracy of the experimental measurements in most instances. Equation 7 is applied in this paper to study the solubility of hydrocarbons in water. The partial molal volumes of the hydrocarbons dissolved in water TTere not available to permit a direct calculation of the solubility of pure hydrocarbons in water. Therefore] the existing thermodynamic data for the pure components and the vapor-liquid equilibria data for the binary hydrocarbon-water systems were applied to compute the modified Henry's law constants and the partial molal volumes of the dissolved hydrocarbons. Since the concentrations of water in the hydrocarbon-rich phases are small, or become large only a t relatively low pressures, ideal solution may be assumed in that phase. Then, the fugacity of the hydrocarbon, f2, in Equation 7 may be estimated from = f;X:
(2)
P,
TI and R = pressure, temperature] and gas constant, respecti~ely;52 = partial molal volume of dissolved gas; fi = partial molal fugacity of solute gas a t the total pressure; N z = mole fraction of dissolved gas.
Equation 2 may be integrated a t constant temperature under the supposition that 62 is independent of pressure and is unaffected by the small change in the concentration of the gas dissolved in water with pressure-Le., N Z is substantially constant-to give Equation 3.
The integration was made between the limits of the vapor pressure, pa, of the solvent and the total pressure, P. For the fugacities] the corresponding limits are Ti, the partial molal fugacity of the solute gas a t the saturation pressure of water, and 72. For an infinitely dilute solution Henry's lam applies, Equation 4.
(6)
Figure 14.
Composition of Hydrocarbon-Rick Phase
at Three-phase Critical Conditions
(8)
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O F GRAPHICALLY SMOOTHED DATAWITH THERMODYNAMICALLY SMOOTHED VALUES TABLE VII. COMPARISON Pressure,
Lh./Sq. Inch Abu.
500 1,000 1,500 2,000 3,000 4,000 6,000 8,000 10,000
100" F. Graph. Thermo.
0.004650
400 600
800 1,000 1,500 2,000 3,000 4,000 6,000 8,000 10,000
0.001067 0.001122 0 001133 1000 F.
200 400 600 800 1,000 1,500 2,000 2,500 3,000 4,000 6,000 8,000 10,000
230 400 600 800 1,000 1,500 2,000 2,500 3,000 4,000 6,000 8,000 10,000
0.000210 0.000212 0.000214 0.000215 0.000217 0.000221 0.000226 0.000225 0.000229 0.000227 0.000230 0.000230 0.000235 0.000242 0.000246 0.000248 2200 F. 0.000118 0.000217 0.000280 0.000305 0.000316 0.000326 0.000336 0.000345 0.000353
Mole Fraction i n Water-Rich Phase 220' F. 280° F. Thermo. Graph. Thermo. Graph. Thermo.
160' Graph.
F.
0.000503 0.000954 0.001310 0.001612 0.002130 0.002572 0.003254 0 003736 0.004210
0.000505 0.000942 0.001325 0.001636 0.002163 0.002582 0.003242 0.003772 0.004221
11ethnne0 000463 0.000484 0.000937 0.000925 0.001322 0.00131 1 0 001643 0 00165.5 0 002218 0 002234 0 002702 0 002705 0 003462 0 003452 0 004037 0 004039 0 004536 0 004523
340° F. Graph. Thermo.
--
-"..-..0 000332
0.000352 0 000290 0.000481 0 000443 0.000579 0 000578 0.000652 0 000677 0.000748 0 000841 0.000798 0 000952 0.000869 0 001091 0.000934 0 00117 0.001015 0 001286 0.001120 0 001398 0.001193 0 001516 wpane----
130° ~ _ 1' . _ 0.000160 0.000166 0.000212 0.00b204 0,000214 0.000210 0.000216 0.000215 0.000218 0.000218 0.000223 0.000223 0,000228 0.000227 0.000231 0.000231 0,000235 0.000236 0.000241 0.000251 0.000257 0.000261 250° F. 0.000117 0.000119 0.000231 0.000226 0.000311 0.000303 0.000356 0.000351 0.000379 0.000374 0.000400 0.000399 0.000414 0.000416 0.000429 0.000430 0.000443 0.000444 0.000464 0.000497 0.000620 0.000537
-
0 000469 0 000584 0 000679 0 000845 0 000944 0 001069 0 001161 0 001300 0 001409 0 001504
0.000486 0.001007 0.001500 0.001947 0.002702 0.003304 0.004262 0.005062 0.006787
0.000523 0.001048 0.001521 0.001951 0.002688 0,003311 0.004317 0.005120 0.005817
0.000343 0.000514 0.000677 0.000814 0.001068 0.001233 0.001452 0.001587 0.001785 0.001913 0.002012
0.000361 0.000533 0.000682 0.000812 0.001064 0.001237 0.001458 0.001603 0.001799 0.001934 0.002029
0.000545 0.001210 0.001819 0.002380 0.003440 0.005640 0.004223
0.006676 0,007747
0.006790 0,007761
~-
160' F.
1900 F.
0.000139 0.000228 0.000231 0.000234 0.000236 0.000241 0.000246 0,000251 0.000254 0.000261 0.000269 0.000273 0.000274 2800 F. 0.000116 0,000114 0.000248 0.000238 0.000345 0.000332 0.000409 0.000399 0.000444 0.000439 0.000493 0.000494 0.000525 0.000524 0.000550 0.000556 0 000577 0.000575 0.000606 0,000665 0.000712 0.000757
0.000127 0.000224 0.000256 0.000260 0.000264 0.000272 0.000278 0.000284 0.000288 0.000296 0.000306 0.000311 0.000312 310' F. 0.000115 0.000112 0.000268 0.000248 0.000380 0.000364 0.000463 0,000454 0.000513 0.000520 0.000616 0.000622 0.000686 0.000680 0.000733 0,000728 0.000770 0.000770 0.000849 0.000991 0.001123 0.001249
-
0.000567 0.001252 0,001872 0.002428 0.003377 0.004190 0.006533
0.000345 0.000593 0.000836
0,000375 0.000609 0.000819 0.001007 0.001400 0.001691 0.002146 0.002383 0.002769 0.003039 0 003241
where f d is t h e fugacity of-the pure hydrocarbon a t the e q u 111b r iu m pressure and temperature, and 2 v ' ~is the mole fraction of the hydrocarbon in the hydrocarbon-ri c h phase. The c o n c e n t r a tions of water in the dew point gas for the methane-water systems (24) were obtained from the data of Sage and Lacey and applied in Equation 7 . The fugacity data of the pure hydrocarbons, methane, ethane, and propane, were obtained from the data prepared by Sageand Lacey(S0). The concentration of water and propane and the solu-
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Figure 17. Modified Henry's Law Constants Solubility of Pure Light Hydrocarbon, Hydrogen, and Nitrogen in Water
for
Figure 16. Determination of Constants i n Thermodynamic Equation for Solubility of Propane in Water
bility of propane in water were obtained by the authors. The solubilities of methane and ethane in water were obtained from Culberson, Horn, and McKetta (6) and Culberson and McKetta (7,8). The Henry's law constants, K ' , and the partial molal volumes of the dissolved hydrocarbons were determined by isothermal plots of log-f 2 against P/2.303RT.
N2
Figure 15 shows this relation-
in Equation 7 were determined for several isotherms for the methane-water and the ethane-water systems up to 10,000 pounda per square inch absolute and for the propane-water system up to 3000 pounds per square inch absolute in Figure 16. These constants were substituted in Equation 7 to compute smoothed values of the solubility of hydrocarbon in water over the range of pressure and temperatures. The agreement between the graphically smoothed experimental data and the thermodynamically smoothed data is good, as may be seen from Table VII. The calculated solubilities of propane in water for pressures from 3000 to 10,000 pounds per square inch absolute are included in Table VII. The validity of the extrapolation is s u p ported by the thermodynamic calculations made on the methanewater and the ethane-water systems up to 10,000 pounds per square inch absolute. Both the methane-water and ethanewater systems show a remarkable isothermal constancy of & with respect to pressure from 1000 to 10,000 pounds per square inch and good agreement between the experimental and calculated solubilities. Figure 17 gives the modified Henry's law constants, K ' , as functions of temperature for the solubility of methane, ethane, propane, hydrogen, and nitrogen in water. The partial molal
ship for the ethane-water system. For any given isotherm, the calculated points were found to lie very close to a straight line, indicating that the partial molal volume of the gas, vz, is substantially independent of pressure. Some scattering of the points occurred a t low pressures. The greater relative inaccuracy of the experimental s o l u b i l i t y TABLE VIII. MODIFIED HEN Y'S LAWCONSTANTS A N D PARTIAL MOLAL VOLUMES O F DISSOLVED data of the hydrocarbon in GASES water at low pressures and the Methane Ethane Propane Hydrogen Nitrogen higher water concentrations in Temp., L~~ K,,, 'jzb L~~ K'a &b Log K'a 82b log K t a ilb LOG K ' a GZb the hydrocarbon-rich phases F. . . . . . . . 6.4291 32 ... 0.3195 . . . . 0.519 may account for the increased .... 6.5232 0.3115 6.6055 0.526 77 1 : 220 5.841 5 780 o:s49 5 ; 8522 .... .... .... o:570 100 deviations. With increased ... 122 6.5544 0.3133 6.7120 0:534 1:iiz 5:9i35 .... ... water concentrations in the 130 5 : 956 5 : 970 6.0593 1.285 .... 160 0:605 0:858 .... 6.7509 0 : 545 ... ... hydrocarbon-rich phase at low 167 6 : io63 i:3i7 ... 190 pressures, the assumption of .... 212 6.5029 0: 3420 617330 0 : 579 6.1158 1 : 303 5 ; 969 0: 652 5:996 0:9i7 .... .... .... .. .... ideal solutions in that phase 220 6,1027 1.275 250 . . . . .... .... 6.0714 1,226 5:Q31 5 9070 0:667 1:021 . . . . .... .... . .. may lose its validity. It has 280 .... .... .... .... ... 6.0320 1.020 310 been found that the deviations 5,815 0 677 5:a27 1 : 625 .... ... .... .... .... ... 340 from a straight line on Figure _. Lb. 15 are produced by relatively a (Sq; inch) (mole fraction). small changes in the values of b Cu ic f o o t per pound-mole. Nz. The values of K' and & . I . .
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These thermodynamic calculations show that the solubility
of pure light hydrocarbons can be predicted h o m accurate atmospheric solubility data, the partial molal volumes of the hydrocarbons dissolved in water, the volumetric behavior of the pure hydrocarbons a t the elevated pressure conditions, and the concentration of the hydrocarbon in the hydrocarbon-rich phases. The difficulty involved in the evaluation of the partial molal volumes of the hydrocarbon in water solution has been mentioned, For pressures up to 2000 pounds per square inch absolute and 300’ F. the partial molal volumes may be estimated from the apparent volumes of hydrocarbons dissolved in high density oils (3)without introducing serious errors in the calculation. ACKNOWLEDGMENT
0.4
The work was supported by the Stanolind Oil and Gas Go. fellowship. The Phillips Petroleum Co. furnished the pure propane used in this investigation.
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LITERATURE CITED
TEMPERATURE,OE
Bartlett, J . Am. Chem. SOC.,49, 65 (1927). Billman, Sage, and Laoey, Trans. Am. Znst. M i n i n g Met. Engrs., 174, 13 (1947). Brown, Katz, Overfell, and Alden, “Natural Gasoline and the Volatile Hydrocarbons,” Section I, Chap. 11, Tulsa, OMa., Natural Gasoline Association of America, 1948. volumes of the same pure constituents dissolved in water are Chaddock, Ph.D. thesis, University of Michigan, 1940. Clifford. IND. ENG.CEEM..13. 631 (1921). plotted as functions of temperature in Figure 18 and are listed in Culberson, Horn, and M c k e t k , Tr‘ans. Am. Inst. Mining Met. Table VIII. I n Table I X the partial molal volumes of the Engrs., 189, 1 (1950). dissolved methane and ethane, as predicted from their values of Culberson and McKetta, Ibid., 189,319 (1950). apparent specific weights ( 3 ) for hydrocarbon systems, are Culberson and McKetta, J . Petroleum Technol., 3, 223 (1951) Deaton and Frost, Am. Gas Assoc., Proc., 1941, 143. compared with those listed in Table VI11for hydrocarbon systems. Dodson and Standing, “Drilling and Production Practice,” p. The densities of hydrocarbons dissolved in water were obtained at 173,New York, American Petroleum Institute, 1944. a density of 1.0 gram per ml. for the entire liquid, corrected for Dourson, Sage, and Lacey, Trans. Am. Znst. M i n i n g Met. Engrs., temperature by means of the rate of change of water density, 151, 206 (1943). Frolich, Tauch, Hogan, and Peer, IND.ENG.CHEM.,23, 543 with temperature. The comparison indicates t h a t the partial (1931). volumes of the gases dissolved in water are of the same Griswold and Kasch, Zbid., 34, 804 (1942). order of magnitude as the partial volume of the same hydroHanson and Brown, Ibid., 37, 821 (1945). carbons dissolved in liquid hydrocarbons. Krichevsky and Kasarnovsky, J. Am. Chem. SOC.,57, 2168 (1935). Lauhlere and Briscoe, Proc. Pacific Coast Gas Assoc., 30, 121 (1939). TABLEIX. COMPARISON O F PARTIAL MOLALVOLUMESOF Lebeau, compt. rend., 140, 1464, 1572 (1905). DISSOLVED METHANE AND ETHANE FROM BINARY HYDROCARBON- Lewis and Randall, “Thermodynamics,” New York, McGrawWATERSYSTEMS AND HYDROCARBON SYSTEMS (8) Hill Book Co., 1923. McKetta and Katz, IND. ENO.CHEM.,40,853 (1948). Methane” Ethanea McKetta and Katz, Trans. Am. Inst. M i n i n g Met. Engrs., 170, Temp., Hydrocarbon’ Hydrocarbon34 (1947). F. water Hydrocarbon water Hydrocarbon , (21) Michela, Gerver, and Bijl, Physics, 3, 797 (1936). 0.849 0.878 100 0.570 0.586 0.858 0.905 0.613 160 0.605 ENG.CHEM.,34, 1223 (1942). (22) Olds, Sage, and Lacey, IND. 220 0.652 0.651 0.917 0.943 (23)Poettman and Dean, Petroleum Refiner, 25, 635 (1946). 0.712 1.021 1.002 2 80 0.667 (24) Reamer, Olds, Sage, and Lacey, IND.ENG.CHIM., 35, 790 340 0.677 0.646 1.025 1.104 (1943). a Vi, cubic foot per pound-mole. (25)Zbid., 36,381 (1944). (26) Russell, Thompson, Vance, and Huntington, Trans. Am. Inst. Mining Met. Engrs., 160, 151 (1945). (27) Saddington and Krase, J . Am. Chem. SOC.,56, 353 (1934). Sufficient data on the solubility of hydrocarbons in water at (28) Sage, Hicks, and Lacey, Am. Petroleum Znst., “Drilling and low pressure were not available to permit development of a genProduction Practice,” p. 386,New York, American Petroleum Institute, 1938; Refiner Natural Gasoline MfT., 17,350 (1938). eral relationship for estimating Henry’s law constants. How(29) Sage and Lacey, Am. Petroleum Inst., “Drilling and Produoever, the constants presented and discussed here do follow simition Practice,” p. 308, New York, American Petroleum Inlar trends and indicate their similarity for gases of widely difstitute, 1941. ferent critical conditions. No generalized interrelationship has (30) Sage and Lacey, “Thermodynamic Properties of Hydrocarbons,” New York, American Petroleum Institute. been developed for the estimation of the partial molal volumes of (31) Scheffer, F. E. C., KoninkE. Akad. Wetenschap. Proc., 16, 404 other hydrocarbon constituents dissolved in water. Unfortun(1913). ately, the partial molal volumes of hydrocarbons dissolved in (32)Ibid., 17, 834 (1914). water are extremely difficult to determine by direct measurements. (33) Souders, Selheimer, and Brown, IND.ENG. CHEM.,24, 517 (1932). There remains, however, the possibility of obtaining the partial (34) Wiebe and Gaddy, J . Am. Chem. Soc., 61,315 (1939). molal volumes indirectly as in the present analysis. A few (35)Ibid., 62, 815 (1940). experimental values of the solubilities of the hydrocarbon in water a t each temperature over a moderate pressure range will REOmIVED for review September 24, 1951. ACCEPTEDOctober 10, 1952. provide the necessary information to predict the solubilities Presented before the Division of Petroleum Chemistry a t the 121st Meeting of the AMERICAN CHBMICAL SOCIETY, Milwaukee, Wis. at high pressures, Figure 18. Partial Molal Volumes of Pure Hydrocarbons, Hydrogen, and Nitrogen Dissolved in Water
\ - - -
