Phase Equilibria in Hydrocarbon Svstems J
VOLUMETRIC AND PHASE BEHAVIOR OF THE METHANE-HYDROGEN SULFIDE SYSTEM H. H. RE-IIIER, B. €1. S-IGE. i \ D W.IS.L-kCEY Culifornia I n s t i t u t e of
'I'eC.h7lO!Og?.
Hydrogen sulfide is encountered in a number of natural petroleum reservoirs. A knowledge of the Iolumetric and phase behavior of this compound in mixtures with the hydrocarbon components of petroleum is of interest to t h e producing division of the petroleum industry. The molal volume of five mixtures of methane and h > drogen sulfide was determined experimentally a t pressures tip to 10,000 pounds per square inch i n the temperature interial between 40" and 340" F. The compositions of the coexisting phases were established throughout the heterogeneous region a t temperatures abo, e 40" F. The effect of temperature and pressure upon the molal
Xolume of mixtures of methane and hjdrogen sulfide is similar to t h a t found for systems composed only of paraffin hydrocarbons. A maximum two-phase pressure of *lightly less than 2000 pounds per square inch was encountered a t a temperature of approximately 50" F. These measurements contribute to an understanding of the role of hydrogen sulfide in the tolumetric and phase behat ior of petroleum. Before t h e correlation of the phase hehavior of this compound can be completed, i t will be desirable to obtain additional information about this coni pound in binary systems containing a paraffin h>drocarhon of a higher molecular weight than n-butane.
-
I'DROGES sulfide is an important cunipoiieiit of t h e
foul iiii\lurv ds n function of pressure and temperature aboie 40" F. logether with the composition of the coevisting phaars
fluids produced from underground petroleum reservoirs For this reason, it is of industrial interest to determine e\pc,rimentally the volumetric and phase behavior of mixtures of t h e compound and paraffin hydrocarbons. The present study deals with the volumetric and phase behavior of mixtures of methantl and hydrogen sulfide a t temperatures from 40" to 340" F. Thp latter temperature was the upper limit of thermal stability ot hydrogen sulfide ( 1 1 )under the conditions studied. The p r r v n t measureinents include the drtrrmination of the molal vohimr of
I
Pnwrlena 4 , Calif.
throughout the heterogeneous region. In mvestigations of this character, a knoL51edge of the properties of the components is necessary. The volumetric behavior of mPthane has been determined with accuracy by a number of inreGtigatois (4,6, 8. 9). These data establish the influence of Iressure and temperature upon the molal volume of methane nvei the range of conditions investigated in the present n ork FT ith R prohahle m o r l e ~ qthan 0.1.5~o The volunietiicx yroperties of hydrogcn ~ u l f i d e in the single-phaw region arid the s p ( ~ i f i c
1
2000
4000 PRESSURE
moo
8000
I
P O U N D S PER SPLJARE INCH
I 0.2
I 0.4 MOLE
Figure 1. Compressibility Factors for Mixtures of Methane and Hydrogen Sulfide Studied Experimentally a t 220" F.
Figure 2.
976
1
I
0.6
0.8
FRACTION M E T H A N E
Pressure-Composition Diagram for MethmneHydrogen Sulfide System
April 1951
volumes of the coexisting phases have been summarized recently (14). In addition, some new experimental data have been obtained (11). The information available concerning the behavior of the two components suffices for present purposes, although the most iecent experimental measurements ( 2 1 ) have not been utilized in establishing the thermodl namic properties of hydrogen sulfide. T h e experimental background available t o West (14) in calculating the thermodynamic properties of this compound leaves something t o be deeired in the way of completeness.
INDUSTRIAL AKD ENGINEERING CHEMISTRY
0.1
0.2
0 3
3Iole Fraction Methane 0.4 0.5 0 6
0.7
0.8
0.9
...
...
At 40° F. (193)u 24.00 Piesaure, Lb./Sq. Inch Abs. 200 400 600
(845)b 0,6989
. ... ... ,,
(223) 20.83 (1350) 0.7467 23.62
... ...
(259) 18.34 (1652) 0.8078 24.13
Dew Point (387) 11.83
(311) 14.87
Bubble Point (1943)c (1848) 0.8878 1.005
... ...
24.61
... ... ...
...
25.09
...
...
5.27
o:i647 0.8385 0,8198
o:bsg7 0.9436 0.9110
i:i?4 1.087 1.029
1.400
...
...
..I
2.191 1.870 1.647 1.489
0.9875 0.9565 0.9097 0.8753
1.106 1.054 0,9815 0.9345
1.2%5 1.168 1.070 1.004
1.373 1.28.5 1.160 1.074
0.7985 0.7830 0 7385 0 7380
0.8493 0.8283 0.7940 0.7682
0.9000 0.8725 0,8300 0.7990
0.9358 0.9195 0.8678 0 8307
1.014 0.9702 0.9072 0.8628
0.7213 0.7070 0.6942
0,2475 0.~ 3 0 3 o.,i62
0.7755 0.7553 0.7370
0.8022 0.7787 0 7x10
0.8300 0.8030 0.7808
2,750 3,000 3,500 4,000
0.6652 0.6631 0.6591 0.6555
0.7030 0.6989 0.6925 0.6868
0.7491 0,7435 0.7332 0.7235
0.8080
0.8880
0.7995 0.7815 0.7660
0.8705 0.8418 0.8180
0.6810 4,500 0.6518 The methane used in this 0.6755 5,000 0.6478 study was obtained from a field 0.6398 0.6655 6.000 in the San Joaquin Valley, 0.6327 0.6560 7,000 Calif. The gas from the well 0.6470 8,000 0.6255 was essentially pure meth0.6190 0.6383 9,000 10,000 0.6135 0.6313 ane, except that it was in equilibrium with water and contained a small quantity of carbon dioxide. Before use, this gas was passed over (4521a (529) 10 13 8.58 granular calcium chloride, sodium hydroxide, activated charcoal, and anhydrous calcium (1104) (1539) 0 7925 0.8794 sulfate a t pressures in excess of 500 pounds per square inch. 200 27.41 27.73 .4 sample of methane purified 400 I2 04 12.32 600 ... in this way was subjected t o a partial condenmtion analysis 800 ... wvhich showed that the quan1,000 1,250 O:i812 tity of ethane and heavier 1,500 0.7691 hydrocarbons was less than 0.002 mole fraction. Com1.750 0 7602 0.8329 2,000 0.7528 0.8304 buetion analyses indicated that 2,230 0.7463 0.8147 the quantity of nitrogen and 2,500 0.7406 0.8032 other inert gases was markedly 2,750 0 7353 0.7937 less than 0.001 mole fraction. 3,000 0.7301 0.7851 It is believed that the methane 3,500 0.7920 0,7705 employed contained less than 4,000 0.7140 0.7570 0.002 mole fraction of impuri4,500 0.7070 0.7460 ties. 5,000 0.7003 0.7368 The hydrogen sulfide n a s 0.7222 6.000 0.6885 t ,000 0 6773 0.7082 prepared by the reaction between Durifiedalunlinum sulfide 8,000 0.6680 0.6950 and &-free distilled water. 9,000 0.6595 0.6838 10,000 0.6522 0.6720 The gas resulting from this reaction was dried over calcium ( S e e !ootnotm o n p a y e 070) chloride and anhydrous calcium sulfate. It was sublimed twice a t liquid air temperatures and the initial and final portions of each sublimate were discarded. The pullfied ploduct v a s stored in stainless steel weighing bombs (IS). It \vas found that the vapor pressure of the hydrogen sulfide employed varied by less than 0 15 pound per square inch upon a change in quality, or fraction in the gas phase, from 0 15 to 0.85.
0.7142 0.7063 0.6926 0.6803
0.7530 0.7423 0.7242 0.7070
0.6695 0,6595 0.6508
0 6935
- _ (638) 7.02
_
Some decomposition of hydrogen sulfide (11) has been found a t temperatures above 340" F. when it IS in contact with mercury in a chrome-nickel steel container. However, in the present investigation, which involved only mixtures of methane and hydrogen sulfide, no indication of thermal decomposition a t a temperature of 340" F. was noted. This n-as probably in part a result of the snialler fugacity (6) of hydrogen sulfide in the nii\tuies at a given pressure and temperature than was realized in the earlier studies with the pure compound. For thi- reason it is believed
... 25.85 12.43 7 96
1.942 1.646 1 452 1.326
0,7973 0,7776 0.7643 0.7558
...
... ...
... ... ...
1.645
0,6825 0.tm3
25.69 12.28 7.80
,..
1.257 1.168
0.7262 0.7181 0.7114 0.7074
. I .
...
5.73
0.6778 0.6733 0.6697 0.6676
...
...
...
~~
5.54 4.18 3.08 2.389
1,750 2,000 9,250 2,500
...
...
...
(1660jc 1.773
... ... ... ...
...
0:7372
:':
(1933)c 1.202
(58p262)
25.53 12.09 7.57
0.6880 0.6825
o.bi4od
(519) 8.64
25.34 11.80
800 1,000 1,250 1,500
3IATERIALS
977
4.40
3.3.5 2.6!16
At 100" F. ~
~-
(1814) 1.004
Dew Point
(io;!)
yo;?
(1909) 1.221
Bubble Point (1727) e 1.788
28.07 12.94 7 (37
28.40 13.32 8.15
28.68 13.61
... ... . .
j.49
5.95
8.j4
...
4.3:3
...
. . 28.90 13.86 8.82
29 04 14.04 R 03
29 19 14.18 9.11
6.28 4.73 3.49 2.676
8.52 5.01 3 80 3.00
6,G9
6.8Y
4 00
5.33 4.15 3.36
2.151 1.810 1.570 1.407
2.488 2.083 1.813 1.615
2.662 2.270
1.985 1.773
2.817 2.423 2.134 1.917
5.20
3.21
29..':1 14.30 9.31
0.9120 0,8887
i:ii3 1.076 1.018
1.751 1.468 1.299 1.192
0.8704 0.8563 0.8318 0.8102
0.9775 0.9163 0.9064 0 8745
1 122 1 072 1.001 0.9313
1.297 1.216 1.108 1 036
1.470 1.362 1.218 1.122
1.613 1.495 1.329 1.208
1.745 1.610 1.423 1.289
0.7923 0,7785 0.7872 0.7383
0.8478 0.8270 0.7962 0.7722
0 9133 0 8838 0.8393 0 8085
0.9837 0.9435 0.8855 0.8473
1.054 1.004 0.9328 0.8850
1,125 1.065 0.9829 0.9250
1.194 1.123 1,029 0.9610
0.7220 0,707.5 0.6952
0,7%523 0.7348 0.7185
0.7846 0.7G4,j 0.7466
0 818.5 0 7938 0.7718
0.8509 0.8219 0.793U
0.8819
0.9127 0.8758 0,8450
0.9i45
0.8479
0.8210
(Continued o n p a g e 978)
that thermal decomposition did not influence significantly the measurements reported. APPAR4TUS AND PROCEDURE
The equipment and methods used have been describd in detail (IS). The procedure involved the introduction of known quantities of methane and hydrogen sulfide into a relatively thick-walled, chrome-nickel steel vessel. The volume occupied by the mixture under investigation was changed by the introduction or m-ithdrawal of known quantities of mercury. A spiral, electromagnetically driven agitator was provided within the vessel t o assist in obtaining thermodynamic equilibrium. It is believed that the volume of the samplc was known with a probable error of not more than 0.08%. This large uncertainty existed only at small specific volumes encountered at higher pressures ( I S ) .
978
INDUSTRIAL A N D ENG1NEER:NG
CHEMISTRY
Vol. 43, No. 4
The pressure was established by a balance ahich employed ii
piston-cylinder combination
TABLE I.
?rIOL.\L \.OLU.\IES
METHANE-HYDROOEN SULFIDE M O L E FRACTION METHANE (Continued)
O F ~ I I X T U R E SO F
( 2 )calibrated against the vapor
pressure of carbon dioxide at the ice point ( 3 ) . The calibratione of the pressure balance ( I S ) have changed by less than 0.02% during 5 years of use. I t is believed that the pressures were known for all state5 covered in this investigation within 0.057, or 0.1 pound per square inch, whichever was the larger. The temperature of the equilibrium vessel was determined from the resistance of a, strain-free platinum resistance thermometer ( 1 ) located in the oil bath surrounding the vessel. The thermometer was calibrated against the indications of a similar instrument xhich was standardized a t the S a tional Bureau of Standards. The Mueller-type bridge employed in conjunction with the thermometer x a s calibrated also. It is believed that the temperature of the material under investigation iyas known relative t o the international platinum scale ( 1 ) within 0.02" F. The weight of hydrogen sulfide employed in the study of each mixture was established by weighing bomb techniques ( I S ) n l t h an uncertainty not greater than 0.03'%. Methane was introduced from a previously calibrated isochoric reservoir, as described ear1ir.r ( I S ) . The uncertainty in this measurement was riot more than 0.1%. At the end of a particular series of measurements a check was obtained by removing the material involved and determining its quantity by gravimetric methods. The sum of the individual weights of the components as they were introduced agreed within 0.037, x i t h the weight of thr mixture withdrawn. Five different mixtures were investigated and in each case the volumetric behavior was determined at the higher pressures with a relatively large sample. A large part of the sample was then withdrayn ~vhile the system was maintained in a single phase, and the measurements were continued with the remaining smaller sample in order t o establish the behavior of the mixture at, pressures below 1000 pounds per square inch. I n addition to the volunietric measurements, a number of samples of the gas phase were withdrawn from heterogeneous mixtures of methane and hydrogen sulfide. The composition of each of these samples was determined from meaeureinents of its specific weight a t atmospheric pressure and a temperature of 100" F. The uncertaintyin the measurement of the specific weight was lesP than 0.1%. It was found ex-
~
0 1
0.2
~
0.3
hIole Fraction Methane ~ 0.4 0.5 0.6
0.7
0.8
... ...
... ...
, . , .
, . .
...
_
0.9
At 160° F.
Pressure, Lb.,'Sq. Inch. Abc
(909)= 4 .5;
'i1093)
(1389) b 0,9220
(1660) 1.253
zoo
31.25 14 48 8.70
800 1,000 1,250 1,500
5.68 019679
1,750 2,000 2,250 2,500
0.9196 0.8898 0.8684 0.8518
2,750 3,000 3,500 4,000
0.8380 0.8275
4,500 5,000 6,000 7,000
8,000 9,000 10,000
400 600
..
~. ,
3.69
:31.,;2 14.76 $4.08
..
..
... ... 31.h2 15.07 9,4?
32.05 15.33 9.72
Dew Point
... ... Bubble Point , . .
...
...
. . I
, .
... ...
32.29 15.58 9.98
32.45 15.76 10.21
32.57 15.93 10.38
32.65 16.03 10.48
32, 74 16.13 10.59
. .
3.34 2.411
6.91 6.21 3.83 2.913
7.19 5.52 4.17 3.27
7.43 5.76 4.42 3.53
7.69 5.92 4.59 3.71
7.71 6.05 4.73 3.86
7 83 6.24 4.86 3.99
1.204 1.098 1.028
0.9780
1 786 1.463 1.283 1.176
2.282 1.862 1.594 1,420
2.635 2.193 1.881 1.666
2.901 2.449 1.121 1.879
3.10 2.647 2.311 2.058
3.25 2.802 2.459 2.195
3.38 2.924 2.582 2.317
0.7937
0,9447 0.9208 0.8827 0.8543
1.105 1,056 0,9823 0.9328
1.297 1.213 1.098 1.027
1.508 1.390 1.232 1.135
1.699 1.562 1.368 1.244
1.863 1.711 1.492 1.344
1.990 1.830 1,601 1.436
2.108 1,939 1,687 1.516
0.7805 0,7685 0,7473 0,7300
0.8335 0,8168 0.7886 0.7665
0,8978
0,8715 0,8334
0,8060
0,9760 0,9385 0.8853 0.8478
1.066 1.014 0,9405 0.8925
1.156 1.092 1,000 0,9395
1.241 1.164 1.060 0.9865
1.318 1.231 1.109 1.026
1.388 1,290 1.157 1.066
0,7162 0.7042 0.6938
0.7476 0,7320 0.7143
0.7828 0.7623 0.74.55
0.8187 0.7942
0.8575 0,8278 0,8020
0,8960 0.8615 0.8322
0.9340 0.8948 0.8613
0.9695 0.9265 0.8865
1.002 0.9538 0.9125
..
0,8088
(i 17 4.34
...
6.56 3.80
0.7733
At 220IC F. 200 400 600
34.yo 16.~6 10.40
35.12 16.78 10 64
3-5.34 17.03 10.90
35.39 17.29 11.15
35.71 17.44 11.34
35.85 17.59 11.49
35.95 17.72 11.64
36.03 17.80 11.71
36.09 17.87 11.80
7 63 5.03 4.n7 3.02
7.83 ,5.96 3.42
8.08 6.23 4.74 3.76
8.28 6.44 4.98 4.01
8.44 6.62 5.16 4.20
8.59 6.77 5.31 4.35
8.68 6.87 5.43 4.46
8.77 6.96 5.52 4.56
2,740 2.268
-..i,b
2.213 1.943
3.33 2.823 2.444 2.159
3.52 3.02 2.638 2.344
3.67 3.17 2.782 2.486
3.79 3.28 2.898 2.595
3.88 3.38 2.986 2.687
800 1,000 1,250 1,500
7.27 5.33
1,750 2,000 2,250 2,500
1.711 1.430 1.248 1.128
2.326 1.406
1.926 1.681
2,7,50 3,000 3,500 4,000
1.030 1.002 0.9653 0,9068
1 270 1.177 1.069 1 003
1.508 1.381 1.218 1.116
1 737 1.583 1.378 1.240
1.939 1,770 1.528 1.368
2.112 1.926 1.657 1.486
2.248 2,057 1.772 1.578
2.354 2.159 1.868 1.664
2.445 2.247 1,954 1.742
4,500
0.8765 0,8533 0,8208 0,7938
0.9565 0,9235 0,8736 0.8375
1,030
1.000 0,9315 0.8848
1,150 1,086 0,9972 0.9365
1.258 1.176 1.066 0.9910
1.356 1.258 1,045
1.436 1.332 1.187 1.094
1.514 1.400 1.240 1.136
1.582 1.462 1.290 1.174
0.7723 0.7553 0,7415
0,8095 0.7878 0,7702
0.8300 0.8230
0.8928 0.8600 0.8345
0,9380 0,8990 0,8670
0.9855 0.9355 0,9015
1.026 0.9730 0.9295
1.062 1.002 0.9548
1.094 1.033 0.9823
6,000
6,000 7,000
8,000 9,000 10,000
3.62 1.314
1.882
1.605
1A1
0.8015
1.129
At 280 F. 200 400 600
38.32 18.49 11.85
38 54 18.69 12.06
38.78 18.91 12.27
38.98 19.10 12.46
39.12 19.26 12.63
39.24 19.37 12.75
39.31 19.47 12.86
39.37 19.53 12.92
39.41 19.59 12.99
800 1,000 1,250 1,500
8.49 6.46 4.81 3.67
872 6.70 5.07 3.96
8.93 6.93 5,32 4.2.:
9.13 7.14 5.54 4.48
9.31 7.32 5.73 4.67
9.31 7.45 5.87 4.82
9.55 7.57 5.99 4.94
9.63 7.65 6.07 5.02
9.69 7.72 6.14 5.10
1,750 2,000 2,250 2,500
2.839 2.262 1.872 1.613
3.17 2.620 2.229 1.946
3.48 2.930 2.525 2.218
3.73 3.18 2.766 2.437
3.93 3.37 2.947 2.616
4.07 3.52 3.09 2.756
4.19 3.63 3.21 2.869
4.28 3.72 3.30 2.959
4.35 3.80 3.37 3.03
2,750 3,000 3,500 4,000
1.443 1.325 1.171 1,077
1.733 1,671 1.349 1.215
1.980 1.793 1.527 1.357
2.182 1.980 1.688 1.495
2.352 2.140 1.827 1.615
2.488 2.272 1.952 1.727
2.599 2.379 2.050 1.817
2.685 2.464 2.131 1.893
2.762 2,542 2.203 1.963
4,500 5,000 6,000 7,000
1.017 0,9731 0,9100 0,8690
1.127 1,065 0,9790 0,9220
1.242 1.161 1.053 0,9820
1,360 1.263 1.129 1,040
1.466 1.355 1,201 1.101
1.561 1.439 1.270 1.157
1.639 1.511 1.327 1,206
1.710 1.573 1.382 1.251
1.776 1.631 1.430 1.291
8,000 9,000 10,000
0,8380 0,8100 0,7880
0,8820 0,8500 0,8240
0,9290 0,8890 0,8600
0,9780 0,9330 0,8960
1,027 0.9760 0,9310
1,077 1.017 0,9670
1.118 1.050 1.001
1.157 1.083 1.026
1.191 1.116 1.056
(Concluded Lin p a g e 079)
_
INDUSTRIAL AND ENGINEERING CHEMISTRY
April 1951
TABLE I.
0.2
0.3
hlole Fraction Xertrane 0.5 0.6
0.4
At 340'
0.8
0.7
0.9
F.
Dew P o i n t
(909)a 4.55
(1389)b (1660) 0.9220 1.262
...
...
...
... ...
...
... ...
, . .
-
...
...
...
,..
...
... ...
... ...
...
...
... ...
...
Bubble Point
...
...
...
...
41.88 20.38 13.21
43.06 20.67 13.40
42.23 20.74 13.56
42.37 20.90 13.73
42.47 21.02 13.86
42.56 21 11 13.96
42.63 21 18 14.04
4'2
70 21 2.5 14.10
42.74 21.29 14 16
800 1,000 1,250
9.62 7.46 5.73
9.97 7.82 6.10 4.98
10.14 7.99 6.26 5.12
10.27 8.12 6.40 5,263
10.40 8.24 6.52 5.38
10.47 8.33 6.62 5.48
10.24 8.40 6.69 5.56
10 2Y 8 47 6.76
4.15
4.30
4.44
4.67 4.07 3.60 3.23
4.75 4.15 3.68 3.31
4.82 4.22 3.73 3.38
1,500
4.55
8.80 7.65 5.92 4.77
1,750
3.72
3.96
::%I
2,500
;:Ai8 2.266
: : : $ 7 2.615
i::; i:;: ::& 2.702 2.867 3.01
4.57 3.96 3.50 3.13
2,750 3,000 3,500 4,000
1.988 1.781 1,503 1.327
2.229 2.007 1.691 1.485
2,410 2.179 1.851 1.627
2.576 2.341 1.992 1.754
2.716 2.477 2.119 1.864
2.829 2.587 2.222 1.961
2.934 2.687 2,307 2.040
3.01 2.762 2.379 2.108
3.08 2,827 2 445 2.173
4,500
1.215 1.136 1.030 0,9630
1.346 1.243 1.028
1.467 1.349 1.193 1.098
1.579 1.449 1.271 1.157
1.679 1.539 1.315 1.218
1.768 1.620 1.412 1.274
1.842 1.688 1.471 1.326
1,909 1.749 1.519 1.366
1.966 1.803 1.567 1.405
0.9170 0.8810 0.8510
0.9670 0.9230 0.8880
1.021 0.9690 0.9290
1.075 1.015 0.9700
1.196 1.058 1.009
1.174 1.102 1.046
1.219 1.138 1 074
1.254 1,170 1.103
1.289 1.201 1.131
5,000
6,000 7,000 8,000
9,000 10,000 a
...
(1093) 3.69
600
200 400
pc~rimentally that under thcse conditions the mixtures of methane and hydrogen sulfide deviated only slightly from ideal solution behavior (Y),arid the volumetric behavior could he determined xi-ith relatively high accuracy froin a liriiitcd number of mcasurcments 0 1 the specific weight of i1iisturc.s of known composition. In earh case duplicate samples wew taken and the corresponding specific weight measurement B were made. The probable uncertainty of the rnole frartiori of methane was lees than 0,003. Good agreement was realized hetween values of the composition of the dew point gas destermined from these direct measurements and those obtained from discontinuitiee in the isothermal volume-pressure derivatives for mixtures of constant composition. Similar discontinuities were used i n establishing the bubble poiiit states.
M O L A L VOLUMES O F MIXTURES OF h ~ E T I I I S E - H Y D R O G E N SULFIDE h f O L h FRACTIOY hIETH.4SE (CO/LClUded)
01
Pressure, Lb./Sq. Inch Abs.
979
1.111
5.62
EXPERIMENTAL RESULTS
The experimental volumetric data for five mixtures of methane and hydrogen sulfide a t 220' F. are shown in Figure 1
D e w point pressure expreseed i n pounds per square inch absolute. Bubble point pressure expressed in pounds per square inch absolute. Retrograde dew point pressure expressed in pounds per aquare inch absolute. Volumes expressed in cubic feet per mole.
~
TABLD 11. Pressure, Lb./Sq. Inch
Abs.
Gaa Phaae Mole Volume fraction cu. feet/ methane mole
PROPERTIES I N
Liquid Phase Mole Volume fraction cu. feet/ methane mole
TWO-PHASE REGIOSO F ~IETHANE-HYDROGEN SULFIDE SYSTEM
Equilibriuni Ratio Hydrogen h l e t h a n e sulfide ~
Pressure, Lb./Sq. Inch Abs.
G a s Phase Mole Volume fraction cu. feet/ methane mole
At 40' F. 27.32 23.20 18.57 15.42 13.14 11.42 10.08 9.00 7.35 6.17 5.27 4.55 3.97 8.49 3.06 2.849 2.657 2.360 2.116 1.885 1.690 1.595 1.491 1.253 1,093
0.0000
0.0057 0.0132 0.0212 0.0284 0.0354 0.0424 0,0493 0.0636 0.0783 0.0930 0.1083 0.1250 0.1433 0,1635 0.1750 0.1868 0.2137 0.2450 0.2798 0.3240 0.3492 0.3758 0.4401 0.5500
~~
~
Liquid Phase Equilibri u m Ratio Mole Volume fraction cu. feet/ Hydrogen methane mole M e t h a n e sulfide ~
At loOD F. (Contd.) 0.6614 0.6634 24:io 0.6661 21.14 0.6688 18,42 0.6715 16.20 0.6740 14.50 0,6766 13 10 0.6790 11.92 0.6844 10.05 8.63 0.6901 7.51 0.6960 6.59 0.7026 5,79 0.7098 5.09 0.7183 0,7282 4.48 4.18 0.7337 3.91 0.7397 0,7539 3.40 2.933 0.7719 2,528 0.7938 0,8253 2.139 1.955 0.8445 1.779 0.8610 1.393 0.9263 1,000 1.093
1.0000 0.8678 0.7313 0,6236 0.5554
0,5052 0.4646 0.4335 0.3851 0.3521 0.3320 0.3206 0.3152 0.3133 0.3202 0,3249
0.3313 0.3482 0.3728 0.4062 0,4540 0,4874 0,5209 0.6910 1 0000
1750 1800 1850
1900 1907'
0.4917 0.4797 0.4580 0.4190 0.3880
1.723 1.599 1.461 1.285 1.184
0.0000 0.0196 0,0592 0,0946 0 , I553 0.2021 0.2367 0.2534 0.2646 0.2811 0,2775
5.31 5.17 4.87 4.60 4.11 3.65 3.22 2.991
0.2725 0.2940 0.3185 0.3378 0,3880
0.9648 0.9947 1.038 1.106 1,184
1.813 1.632 1.438 1.171 1.000
0.8581 0.8614 0.8686 0.8786 0.8930 0.9116 0.9340 0.9478 0.9620 0.9955 1.036 1.104 1.189 1.293
1.0000 0.9834 0,9502 0.9208 0.8716 4 . &O 0.8363 3.81 0.8139 3,jP 0,8045 0.8005 3.25 2.754 0.8006 2.229 0.8252 1,668 0.8778 1.234 0.9131 1.000 1.0000
0.6946 0.7370 0.7953 0.9047 1,0000
At 160° F.
778 9" 800 850 900
1000 1100 1200 1250 1300 1400 1500 1600 1650 1660h
0,2580 0 2295 0.2090
2.792
2.347 1.951 1.619 1.399 1.293
0.0000
0.0031 0.0098 0.0167 0.0309 0.0459
0.0622 0.0720 0.0814 0.1021 0.1245 0.1547 0.1830 0,2090
...
6.39 6.01 ;7,6G 5.03
Vapor pressure, hydrogen sulfide. Estimated critical s t a t e .
At looo F.
394a 400 450
500 550 600
700 800 900 1000 1100 1200 1250 1300 1400 1500
1600 1700
0.0000
11.68 0.0117 11.50 0.0963 10.17 9.11 0.1642 0.2203 8.24 7.50 0.2688 6.35 0.3416 5.48 0.3976 4.76 0.4396 0,4707 4.17 3.69 0.4923 3.28 0.5079 0,5130 3.10 0,5182 2.939 0.5240 2,656 0.5265 2.322 2.093 0.5195 1.851 0.5058
0.0000
0.0007 0.0067 0.0128 0.0190 0.0255 0.0385 0.0523 0.0670 0.0828 0.0996 0.1182 0.1282 0.1390 0.1620 0.1885 0.2192 0.2832
0,7313 0.7317 0,7343 0.7373 0.7410 0.7443 0.7518 0,7601 0,7697 0.7802 0.7922 0.8061 0.8140 0,8230 0.8430 0.8680 0.8992 0.9398
1.0000 i$.'i5 14.37 12.83 11.58 10.54 8.88 7.60 6.66 5.68 4.94 4.29 4.00 3.73 3.23 2,788 2 370 1.998
0.9890
0.9098 0.8166 0.7918 0,7505 0,6847 0,6357 0,6007 0.5771 0.5638 0.5586 0.5586 0.5596 0.5681
0.5840 0.6091 0.6513
T.IBLE111. UNIQUESTATESFOR METEANE-HYDROGEX SULFIDE SYSTEM Mole Fraction Methane
0.1 0.2 0.3 0.4 0.5 0.6 0.7
Critical Pressure, lb./sq. inch Temp., F. abs.
1473 1647 1812 1915 1954 1936 .
.
I
190.3 162.6 130.0 95.8 58.9 21.2
...
194.9 177.1 155.6 132.4 106.8 78.1 48.9
1370 1416 1457 1465 1446 1382 1276
1491 1670 1826 1914 1954 1939
...
185.3 156.1 125.1 90.1 79.2 43.0
..
980
INDUSTRIAL AND ENGINEERING CHEMISTRY TABLE IV.
Vol. 43, No. 4
EXPERIMENTAL DATAFOR M E T H ~ X E HYDROGEN SULFIDE SYSTEM
S L v P L E OF
Mixture 1
M eight fraction merhane R eight fraction hydrogen sulfide At 40° F. Pressure. 1.b.: Sir. Inch .Abs.
-_9863.2
5:pecific CoinpresVolriIne. sibility C u . Foot,'Lb. l'actor T e s t 1077 0.020112 0.020180 0.020312 0.020805 0.020770 0.031021 0.021377 0 021689
P535.3 8842.4 8097.5 (040.5 0130.6 4944.i
4027.,
1.15177 1.11724 1.05462 0.96406 0.84805 0.74825 0.61366 0.50721
0 08396 0 91604
Pressure, Lh./Sq. Specific C'i,.iipresInch Volume, aiiiility Abs. Cu. F o o t / L b . Fnctor
__ 534 2
T e s t 1079 0,073691 0.080994 0.090926 0.108363 0,135759 0.15P832 0.1!30222 0,223340
502.5 467.6 421.3 371.8 342.2 314.9 292.4
~~
~~~
~
0 11857 0.236X1 0.24688 0 26507 0.29307 0 RIi.iC? 0 3.tTi2
0.38291
v.
TABLE SAMPLE O F &PERIliENThL C~MPOSITIONS OF ( i . 4 ~ PHASE IN HETEROGENEOCS h,lIXTURES OF hlETH.4NE .%XI)
HYDROGEX SULFIDE At 40° F.
Pressure, Lb /Srl Inch Abs. 253.6 725,4 1105.8 1596.0
Figure 3.
Equilibrium Ratios for 3Iethane and Hydrogen Sulfide
This temperature was above the critical temperature of hydrogen sulfide and no two-phase region existed. The density of the experimental points shown in Figure 1 is repreeentative of that obtained a t five other temperatures from 40" to 340" F. The experimental volumetric data were smoothed by residual graphical operations t o even values of pressure and composition. It ie believed t h a t the graphical techniques employed did not contribute more than 0.05% to the uncertainty of the results. Values of the molal volume for nine mixt,ures are presented in Table I. The corresponding values for pure methane and hydrogen sulfide were not included because they are available elsewhere (9, 11).
By use of the d a t a concerning bubble point and dew point states obtained from the volumetric measurements and the directly measured composition of the dew point gas (IO), the phase behavior in the heterogeneous region above 40" F. was established. A pressure-composition diagram based upon these results constitutes Figure 2. The composition and molal volume of the coexisting phases are recorded in Table 11. These values were calculated by suitable graphical operations from data of the t-ype presented in Figures 1and 2. I n addition, gas-liquid equilibrium ratios for methane and hydrogen sulfide are included in Table 11. It is improbable t h a t the compositions of the coexisting phases involve uncertainties greater than 0.003 mole fraction and the molal volumes of these phases are knorrn with a probable error not greater than O.3y0except near the critical state. T h e product of the equilibrium ratio and p r e s u r e , which is a convenient quantity for graphical use, is presented in Figure 3. The behavior of hydrogen sulfide is qualitatively similar t o that found for hydrocarbons of intermediate volatility ( 1 8 ) . €Ionever, in the case of this binary s)-stem the equilihrium ratio for methane appears to increase lcss rapidly nezr den- point with a decrease in pressure than is the ease in hinary hydrocarbon systems of similar character (12). This rc>sults in the maxima indicated for the product of the equilibrium ratio for methane and pressure shown in Figure 3. Table 111 records estimated values of the properties a t the unique states of the system. I n addition to the critical states, values of the maximum pressure and tempcmture at n-hich tlvo
1831.9
Mole Fraction
Mole Fraction Hydrogen Sulfide 0.7142 0.3168 0.2722 0.2721 0.2921 0.2895 0.3438 0.3462
Me thane 0.2858 0.6832 0.7278 0.7279 0.7079 0.7105 0.6562 0.6538
phases coexist have beeii listed for a series of even-valued compositions. Because these values were obtained by interpolation and extrapolation of the experimental data, they may involve uncertainties in temperature of as much as 2" F. and in pressurr of 23 pounds per square inch. The experimental measurements upon which the forpgoing derived values have been based are extensive. Tatile IV presents a sample of the available ( 1 0 ) volumetric measurements for this system. The corresponding values of prcssurc:, tcmperature, and volume have been recorded for each state inveatiyated. The data sho\m in Table IV are typical of the density of thr nieasurements obtained. T h e experimental values of the ('omposition of devi point gas also are available (10) and a sample of the results a t 40" F. constitutes Table V. I n each case the tabulations carry a somewhat greater number of significant figures than is called for by the experimental accuracy. ACKVOW LEDGMENT
This paper is a contribution from American Petroleuin Respa1,c.h Project 37 located at the California Institute of Technology. Elwood Rogers assisted with the experimental work, anti Betty H. Iienditll and 1-irginia 11. Berry carried out the calculxtions. LI'I'ER4TURE
(I )
CITED
Inst. Physics. "Temperature, Its IIeasurement and C'ontrol in Science and Industry," New York, Rcinhold I'uhlish-
-1iii.
ing Corp.. 1941. ( 2 ) Beattie. J . .A,, arid Bridgeman, 0. C., A n n . P h y s . , Series 5 , 12,827-36 (3932). (3) Bridgeinan. 0 . C . . J . A ? n . Che?ri. ,SOC., 49, 1174-83 (1927). ( 4 ) Keyes, F. G . , and Burks, H. G . , I / ~ i d .49, , 1403-10 i1927). ( 5 ) Kvalnes. H. 11..and Gaddy, V L., I b i d . , 5 3 , 394-9 (19:31). (6) Lev-is. C;. I., J . d m C'iicm. ,Sot., 30, 668-63 (1908). ( 7 ) Lcwis, G . S . .Proc. Am. A c o d . A r t s Sei., 37, 49-69 (1\401). ( 8 ) 1Iichels, h.,and Xederbragt, C . IT.,P h y s i e n , 3,569-77 (1936). (9) Olds, K. H . , Reamcr, H. H.. Sage, R . H., and Lacey. IT. K.,
acey,
K. S . , -1merican
INDUSTRIAL AND ENGINEERING CHEMISTRY
April 1951
Documentation Institute, Washington, D. C., Document 2934 (1950). (11) Reamer, H. H., Sage, B. H., and Lacey, IT. CHEM.,
iY.,IND. ENQ.
42, 140-3 (1950).
(12) Ibad., pp. 534-9. (13) Sage, B. H., and Lacey, W. S . , T r m s . Am. Inst. ,Wining M e t . E ~ Q T s136, . , 136-57 (1940). (14) West, J. R., Chem. Eng. Progrrss, 44,387-92 (1948).
981
RECEIVEDMarch 27, 1950. This is t h e 53rd paper of a series. A bibli.&YO E N O I N E E R I N Q ography of the first 50 articles appeared in INDUSTRIAL CHEmmRY, 41,474 (1949). T h e 5lst appeared in 1949 a n d t h e 52nd in 1950. For detailed tablee supplementary t o this article, order Document 2934 from t h e American Documentation Institute, 1719 ?; St., N.W., Washington 6, D. C., remitting 50 cents for microfilm which yields images 1 inch high on standard 35-mm. motion picture film or 85.00 for photocopies 6 by 8 inches which are readable without optical aid.
Net Heat of Combustion
of AN=F=58Aircraft Fuels SIMON ROTHBERG AND R.4LPH S . JESSUP .Vational Bureau of Standards, Washington, D . C.
T h e work described in this paper was undertaken at the request of the Bureau of Aeronautics of the Department of the Savy to determine whether the heats of combustion of volatile hydrocarbon liquids used as jet-propulsion fuels could be correlated with more easily measured properties of the fuels. Experimental measurements of heats of combustion were made on 32 liquid fuels meeting the specifications for iN-F-58 (now MIL-F-5624) jet-propulsion fuels. It was found that the data on these fuels and data previousl,
T
IIIS project was undertaken at the request of the Bureau of Aeronautics of the Department of the Navy, in order t o determine the feasibility of extending t o AN-F-58 (now MIL-F5624) aircraft fuels the relations between net heat of combustion and aniline point, or aniline-gravity product, previously found by Jessup and Cragoe (14) to hold for AN-F-28 aviation gasolines [suprrsrded by AS-F-48 (non- MIL-F-557211. FUELS INYESTIGATED
The thirty-two fuel samples investigated were submitted by individual refiners. The fuels were selected by the Bureau of Aeronautics of the Department of the S a v y , in cooperation with the Department of the Air Force and the Kational Advisory Committee for Aeronautics. The fuek were selected to cover as wide a range as possible of properties likely to be significantl>related t.o heat of combustion, such as :~iiiiinepoint, gravity, aromatic content, etc. The producers of the fuels investigatcd and the number of samples eupplied by each are listed helo~v. Producer
s o . of Salliple% 2
2 1
,]
2
? 1
B 3
LVIT OF HEAT
Heats of combustion were measured in terms of the absolute
in air was made by means of the factor.
reported from this bureau on 57 aviation gasolines coi~lcl be represented accurately by a linear equation expressing net heat of combustion as a function of the product of aniline point in degrees Fahrenheit and gravit) in degrees
4.P.I. As a result of this finding it is possible to mdke reliable estimates of the heats of combustion of a considerable \ ariety of hydrocarbon fuels without the necessity of making experimental determinations, u hich are difficult and ti me-cons ti m i np. 1 absolute joule/grani = 0.429929 B.t.u./pound ( 2 )
The British thermal unit modern steam tables.
SO
defined is the unit used in a11
APPAR.ATUS AND METHOD
The aniline points of the furls ( 5 ) , ;I.P.I. gravities ( 4 ) , sulfur contents ( 6 ) ,and dielectric constants and dissipation factors for the fuels (7) were determined in accordance Lyith methods of the American Society for Testing Materials. The carbon and hydrogeii contents 7':ere determined by mici oc~cmbustionanaly-is. all lveights being reduced to vacuum. For t,he fuels uridvr consideration the dissipation factore are practically equal t o the dielectric power factors. The estimated uncertainties (average deviations based 011 duplicates) in the values reported for these properties are XP follow: aniline point *0.2" F.; gravity *0.05" X.P.I.; sulfur carbon content content *0.005yo; hydrogen content *O.l%; =+=O.l%: dielectric constant *O.l%c; dissipation factor 1.0.2 X The carbon contents are not reported in this paper. The sum of the carbon, hydrogen, and sulfur contents of thr various fuels ranged from 99.7 to 1 0 0 . 3 ~ 0 . The assigned uncertainties, except iri the case of the hydrogen contents, are too Emall t o introduce significant errors into the equations given later in this paper, relating net heat of combustion t o aniline point, aniline-gravity product, hydrogen content, and dielectric constant. The bomb calorimeter, accessory apparatus, and method of calculating results on gross heat of combustion have been described (16). Thin-walled glass bulbs (11, 14, 1 6 ) were used to contain the liouid samules.
the bulh is alternately heated t o expel air and aliowed to cool
