Phase Equilibria in Hydrocarbon Systems VOLUMETRIC BEHAVIOR OF n-NONANE L. T. CARMICHAEL, B. H. SAGE, AND W. N. LACEY California Institute of Technology, Pasadena, Culif. P
I
N RECENT years the experimental background concerning the volumetric behavior of the aliphatic hydrocarbons has increased rapidly. However, no information appears to be available for the effect of pressure and temperature upon the molal volume of n-nonane except for conditions near atmospheric pressure. Rossini (2) reported the specific weight of nonane a t several temperatures for atmospheric pressure. These data were supplemented by the measurements of Wibaut ( 4 , 5 ) , who also reported the vapor pressure of n-nonane at temperatures up to 300" F. The present study includes values of the molal volume of n-nonane for temperatures between 100' and 460" F. and for pressures up to 10,000 pounds per square inch, Vapor pressures were measured a t temperatures between 280" and 460" F. APPARATUS AND METHODS
The apparatus used in these studies has been described ( 3 ) . The method involved the introduction of a known quantity of 72-nonane into a stainless steel container, the effective volume of which could be varied by the introduction or withdrawal of mercury. The temperature of the stainless steel vessel was controlled by immersion in an agitated oil bath, the temperature of which was related t o the international platinum scale by means of a platinum resistance thermometer of the strain-free type. This instrument was calibrated against a reference resistance thermometer which had been standardized at the National Bureau of Standards. Experience with this equipment indicated that with reference to the international platinum scale the temperature of the contents of the stainless steel vessel was known with a probable error of 0.02 F. The attainment of equilibrium was hastened by agitation of the system by means of a magnetically operated cage that was rotated within the stainless steel pressure vessel. The apparatus was O
calibrated by the introduction and withdrawal of mercury as a function of pressure and temperature. A review of the precision of these calibrations and of the small systematic trends experienced in the coefficients of the analytical expressions describing the changes in volume of the stainless steel vessel with pressure and temperature leads to the conclusion t h a t the volume OGcupied by the n-nonane was known with a probable error of 0.25% at pressures below 5000 pounds per square inch. At the higher pressures the probable error may have been as large as 0.35%. The pressure was determined by means of a special balance ( 3 ) which was calibrated against the vapor pressure of carbon dioxide a t the ice point (1). The calibration of this instrument has changed by less than 0.05'% in a 15-year period. It is believed that the pressures recorded were known within 0.05% or 0.2 pound per square inch, whichever is the larger measure of uncertainty. The vapor pressure was measured at temperatures above 280' F. for two different total volumes of the system. ilt temperatures of 280" and 340' F. a mercury-in-glass manometer was employed in order to establish the vapor pressure since the probable error of measurement was somewhat less than that associated with the balance that was designed for use a t high pressures. MATERIALS
The n-nonane employed in this study was obtained from Project 44 of the American Petroleum Institute. After deaeration by extended refluxing a t pressures below 0.1 pound per square inch, the specific weight a t 77 F. and atmospheric pressure was found to be 44.558 pounds per cubic foot as compared with a value of 44.563 pounds per cubic foot reported by Rossini ( 2 ) . The index of refraction relative to the D-lines of sodium wm found t o be 1.40338 as compared with a value of 1.40316 given by Rossini ( 2 ) . After completion of the laboratory investigaO
TABLEI. EXPERIMEKTAL VOLUMETRIC MEASUREMENTS OF Pressure, Molal Volume, Lb./Sq. Inch Cu. Ft./ Absolute Lb. Mole
Pressure, iMolal Lb./Sq. Volume Inch Cu. F t . ) Absolute Lb. Mole
Pressure, Molal Lb./Sq. Volume, Cu. Ft./ Inch Absolute Lb. Mole
Pressure NIolal Lb./Sq,' Volume Cu. Ft.) Inch Absolute Lb. Mole
looo F.
160' F . 34.2 3.0138 124.2 3.0254 3.0152 484.3 9 3 5 . 3 2.9998 1947.1 2.9690 2.9433 2887.3 2.9126 4034 7 2.8882 5041.2 5964.0 2.8728 2.8510 6981.0 2.8305 7997.8 2.8125 8908.5 2.8023 9584.1
220° F. 7 2 . 3 3.1575 465.5 3.1383 961.1 3.1190 3.0716 2143.5 3,0344 3173.3 3.0075 4073.4 5137.6 2.9780 6039.6 2,9562 7046.7 2.9344 2.9215 7782.0 2.8997 8965.9 2.8856 9606.2
280q F. 10.1 4.6414 10.2 3.7731 118.9 3.3024 629.6 3.2678 1724.6 3.2062 3036.4 3.1473 4589.5 3.0857 6038.3 3.0395 7550.2 3.0015 8893.8 2.9703 9944.6 2,9459
132.7 448.8 937.4 2,013.7 3 028 6 4:053:2 5,076.6 6,026.6 7,047.1 8,031.6 9,121.9 9,858.7
2.9151b 2,9074 2.8946 2,8690 2.8446 2.8228 2.8035 2.7856 2.7715 2.7612 2.7484 2.7381
252.6 559.9 940.0 1,255.5
2.9100 2.9023 2.8908 2.8805
476.5 1,923.3 4,001.8 6,049.8 8,085.6 10,029.9
2.8972 2.8625 2.8125 2.7753 2.7510 2.7279
.z
n-NONANEa
Pressure Molal Lb./Sq.' Volume Inch Cu. Ft.) Absolute Lb. Mole 340' 24.1 24.2 87.6 485.2 1444.8 2998.8 4574.6 5977.7 7338.0 8534.1 9588.4
F. 4.7299 7.7001 3.4781 3.4499 3.3576 3.2652 3.1870 3.1293 3.0857. 3.0511 3.0229
Pressure Molal Lb./Sq.' Volume, Inch Cu. Ft./ Absolute Lb. Mole 400' 50.3 50.9 98.4 370.1 915.1 1991.6 3460.2 4901.0 5921.8 6905,4 7655.0 8704.5 9477.1
F. 5.0492 6.2573 3.6962 3.6513 3.5769 3.4666 3.3550 3.2755 3.2268 3 1909 3.1614 3.1280 3.1024
Pressure Molal Lb./Sq.' Volume, Inch Cu. Ft./ Absolute Lb. Mole 460' 96.4 97.0 139.3 992.4 1971.2 3033.2 4615.4 6048.1 7589.2 8923.8 9804.9
Sample weight = 0 . 2 7 6 0 2 pound. iMolecular weight n-nonane = 128.250. Five significant figures were carried to increase the precision of representation of the experimental data.
2697
F. 5.0556 6.2227 3.9847 3.7706 3.6282 3.5166 3.3961 3.3153 3.2486 3,1960 3.1652
2698
INDUSTRIAL AND ENGINEERING CHEMISTRY
TABLE 11. Pressure, Lb./Sa. Inch Absolute
XIOLAL L'OLUMES O F
Vol. 45, No. 12
n-NONANE I N LIQIXDP H A S E
~
130° F. 160° F. 190° P. 220° F. 250' F. 280° F. (0.179); (0.438) (0.961) (1.92) (3.57) (6.23) (10.28) Bubble Point 2.914 2.971 3.03 3.09 3.16 3.23 3.32 3.02 3.08 3.18 3.22 3.30 2.909 2.965 200 3.02 3.08 3.21 3.28 2.905 2.959 3.14 400 3.07 3.13 3.20 2.953 3.01 3.27 600 2.900 3.19 3.26 3.00 3.06 3.12 2.946 800 2.895 2.997 3.05 3.12 3.18 3.24 2,890 2.942 1 000 3.17 3.04 3.11 3.23 1' 250 2.884 2.935 2.989 3.16 3.22 2.877 2.929 2.981 3.04 3.10 1: 500 3.14 3.20 2.974 3.03 3.08 2.870 2.922 1,750 2.966 3.02 3.08 3.13 3.19 2.866 2.915 2 000 2.960 3.01 3.07 3.12 3.18 2.859 2.909 2'250 3.11 3.17 2.853 2.902 2.952 3.00 3.06 2' 500 3.10 3.16 2.996 3.05 2.895 2.945 2:750 2.846 2.889 2.940 2.987 3.04 3.09 3.15 3 000 2.840 3.13 3.02 3.07 2.876 2.927 2.974 3'500 2.830 3.06 3.11 2.865 2.914 2.961 3.01 4' 000 2.818 3.04 3.09 2.948 2.994 2.855 2.900 4:500 2.808 3.07 2.980 3.03 2.889 2.938 2.799 2.845 5 000 3.04 2.956 2.999 2.825 2.869 2.914 6'000 2.781 3.01 2.893 2,935 2.975 2.765 2,810 2.850 7'000 2.990 2.872 2.916 2.955 2.791 2.830 8: 000 2.755 8,000 2.744 2.779 2.814 2.854 2.895 2.933 2.967 10,000 2.730 2.764 2.800 2.836 2.872 2,908 2.944 a Figures in parentheses represent vapor pressures in pounds per square inch absolute. Volumes are expressed in cubic feet per pound mole.
w
100° F.
340' F. (24.53) 3.50 3.47 3.45 3.43 3.41 3.39 3.37 3.35 3.33 3.32 3.30 3.29 3.27 3.26 3.24 3.21 3.19 3.17 3.13 3.09 3.07 3.04 3.02
370° F. (36.23) 3.60 3.57 3.54 3.52 3.50 3.48 3.45 3.43 3.40 3.38 3.36 3.35 3.33 3.32 3.29 3.26 3.24 3.22 3.17 3.14 3.10 3.08 3.05
400" F. (51.04) 3.71 3.69 3.65 3.62 3.59 3.56 3.53 3.51 3.48 3.46 3.44 3.42 3.40 3.38 3.35 3.32 3.29 3.27 3.22 3.18 3.15 3.12 3.09
430' F. (70.57) 3.83 3.81 3.77 3.73 3.70 3.66 3.63 3.60 3.57 3.54 3.52 3.50 3.47 3.45 3.41 3.38 3.35 3.32 3.27 3.23 3.19 3.16 3.12
460° F. (96.24) 3.97 3.94 3.90 3.85 3.81 3.77 3.73 3.69 3.66 3.62 3.60 3.57 3.54 3.52 3.48 3.44 3.41 3.38 3 32 3.27 3.23 3.19 3.16
cate set of data was obtained a t 100" F. The resultsagreed with the first set of measurements within 0.3%. The small but systematic difference between the initial and final measurements was distributed among the sets of data obtained on the basis of the period that the sample was in the equipment. Table I1 records the molal volumes of n-nonane a t a series of even pressures for each of the temperatures experimentally investigated. The standard error of these smoothed data from the experimental measurements shown in Figure 1 was 0.090%. Values of the vapor pressure based upon the critically recorded values of Rossini (2) were included in Table 11.
3 75
d 0
2
3103 F. (16.20) 3.40 3.38 3.36 3.34 3.33 3.32 3.30 3.28 3.26 3.25 3.24 8.22 3.21 3.20 3.18 3.16 3.14 3.12 3.08 3 05 3.03 3.00 2.977
350
8 I-
325
2 u 3 3 00 W
5
9 275
I000
2000
3000
4000
PSESSLRE
5000
6000
POUNDS PER S W A R E
7000
8000
9COO
i x i
Figure 1. Molal Volume of n-Nonane in Liquid Phase
tion, similar measurements were made and showed less than 0.01% change in either the specific weight or the index of refraction. It was indicated by Project 44 that the sample contained at least 0.996 mole fraction of n-nonane and small quantities of isomeric compounds. EXPERIMENTAL RESULTS
A set of measurements was made a t each of seven temperatures between 100" and 460" F. for pressures up to 10,000 pounds per square inch. At each temperature the volume a t approximately ten different pressures was determined. Results of these experimental measurements are recorded in Table I to one more significant figure than the probable error of measurement justifies so that in the treatment of the data the reader may obtain the same precision as the authors. The experimental values are depicted in Figure 1, which serves to illustrate the frequency with which experimental measurements were made. Upon the completion of the measurements a t the highest temperature a dupli-3
Figure 2.
Residual Vapor Pressure of n-Nonane
TEMPERATURE
OF.
December 1953
INDUSTRIAL AND ENGINEERING CHEMISTRY
The vapor pressure of nonane may be approximated by the following expression (2): 2571.860 loglo PR = 5.22152 330.914 t
-
+
in which PL is the reference pressure in pounds per square inch and t i s the temperature in O F. The values of vapor pressure determined by Young (6), Wibaut (4, 5 ) , and the authors have been placed on a residual basis by using Equation 1 as a reference. The residual vapor pressures are shown in Figure 2. P” and P i are the vapor pressure and the reference pressure, respectively. For temperatures below 340’ F. all the experimental data agree with Equation 1 within the uncertainty of the respective measurements. At higher temperatures the deviation of the present measurements is more marked., The pairs of points shown from the authors’ work represent the extremes of variation of the vapor pressure t h a t were encountered with changes in volume from 0 t o 0.3 weight fraction of gas.
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ACKNOWLEDGMENT
This paper is a contribution from American Petroleum Institute Research Project 37 located a t the California Institute of Technology. F. D. Rossini of Project 44 of the American Petroleum Institute kindly furnished the sample of n-nonane used in this work. H. H. Reamer, Betty Kendall, and Elizabeth McLaughlin aided with the accumulation of the experimental data and the preparation of the manuscript. LITERATURE CITED
(1) (2) (3)
Bridgeman, 0.C., J. Am. Chem. Soc., 49, 1174-83 (1927). Rossini, F. D., “Selected Values of Properties of Hydrocarbons,” Washington, D. C., Natl. Bur. Standards, 1947. Sage, B. H., and Lacey, W. N., Trans. Am. Inst. Mining Met.
Engrs., 136,136-57 (1940). (4) Wibaut, J. P., Hoog, H., Langedijk, S. L., Overhoff, J., and Smittenberg, J., Rec. trau. chim., 58, 329-77 ( 1 9 3 9 ) . (5) Wibaut, J. P., and Langedijk, S. L., Ibid., 59, 1220-51 ( 1 9 4 0 ) . ( 6 ) Young, S., Proc. Roy.I r i s h Acad., 38B, 65-92 ( 1 9 2 8 ) . RECEIVED for review June 1, 1953.
ACCEPTED August 3, 1953
Volumetric Behavior of Nitric Acid H. H. REAMER, W. H. CORCORAN, AND B. H. SAGE California Znstitute of Technology, Pasadena, Calv.
N
I T R I C acid has been the subject of many investigations, the volumetric behavior of nitric acid throughout the heterogeneous region from bubble point to a specific volume of 0.2 cubic only a few of which are mentioned here. Yost and Russell (16) reviewed its physicochemical properties and Taylor (14) foot per pound and the characteristics of the condensed liquid reported its fugacity in aqueous solutions. Forsythe and for pressures up t o 5000 pounds per square inch. Giauque (8)investigated a number of its thermodynamic properMETHODS AND APPARATUS ties in aqueous solution. Veley and Manley ( 16) determined the The equipment used for this investigation was similar, in specific volume and the electrolytic conductance of this compound at atmospheric pressure. Recently Sibbitt et al. (12) summarized principle, to t h a t developed by Beattie (1). I t s general arrangement is shown schematically in Figure 1, the physical properties of coneentrated nitric acid and gave some data on the pure compound. This information is primarily A sample of nitric acid was confined within a glass related to the behavior of concentrated nitric acid at physical cylinder combination a t A . This vessel was enclosed w i t e % ; equilibrium. Reference was made to the effect of the relative heavy-walled metal container, B, which was connected through the small steel tubing, D, with volume of the gas phase upon the fluid in’ector, C. A polythe “vapor pressure” a t temmerized, duorinated hydroperatures above 200’ F. carbon filled the space surExperimental information rounding the glass pistoncylinder combination, A , in concerning the volumetric bethe metal vessel, B. The tubhavior of nitric acid at either ing, D,and the injector, C, physical or chemical equilibalso were filled with this fluorium at elevated pressures rinated hydrocarbon. The pressure within the system did not appear to be availwas determined by means of able. Volumetric and phase the mercury-in-steel U-tube -X behavior was determined at shown at 8’. A pressure balchemical and physical equilibance, E ( l o ) ,in conjunction with the manually operated rium (6) for samples of com-C fluid injector, J , was used mercial red and white fuming to measure the pressure withnitric acid. These measurein the fluid-filled portion of ments indicated a marked the system. J was employed Hin order to adjust the intereffect of small quantities of I faces in the mercury-in-steel nitrogen dioxide upon the U-tube, F, t o a predetermined equilibrium bubble point fixed level. pressures. For example, a deB was immersed in an agicrease in the weight fraction tated silicone bath, I (6, 9), of nitrogen dioxide from 0.15 the temperature of which could be controlled within t o 0.03 resulted in approxi0.02” F. The lower part of mately a tenfold increase in C was immersed in an agibubble point pressure. It tated air bath in order to keep was the purpose of the presthe fluorinated hydrocarbon e n t investigation to determine Figure 1. Schematic Diagram of Apparatus at a ronstant temperature
I
1F.
