J. Chem. Eng. Data 1992, 37, 337-338 (4) Sen, U. J . Php. chem.1977, 81, 35. (5) Deck, M. R. J.; Bkd, K. J.; Parker, A. J. A u t . J . Chem. 1975, 28, (8) (7) (8) (9) (IO) (11)
(17) (18) (19) (20) (21) (22) (23) (24)
955. Kab, K. M.; ana,R. J . SoUm Chem. 1977, 6, 733. Krumgalz, 8. J . Chem. Soc.,Faraay Trans. 11980, 76, 1887. ZaM, R.; Desnoyers, J. E.; Perron, G.; Kay, R. L.; Lee, K. J . Phys. chem.1982, 88, 3998. Lankford,J. 1.; Crlss, C. M. J . SdutiOn Chem. 1987, 16, 753. McDOneid, D. D.; Hyne, J. B. Can. J . Chem. 1970, 48, 2416. Hlrakawa, H.; Nomura, H.; Kawalzuml, F. J . Phys. Chem. 1989, 93,
(25) (26)
3784. (12) Heftor, 0.T.; Grolier. J. P. E.; Roux, A. H. J . sdutkn Chem. 1989, 18, 229. (13) Hsftw, G. T.; &olkr, J. P. E.; Roux, A. H.: Roux-Desgrangee. G. J . sacvbbn chem.1990, 19. 207. (14) Kawalsuml, F.; Inone, Y.; Nomura, H. Bu//. Chem. Soc. Jpn. 1991, 64, 510. (15) Krlshnan, C. V.; Friedman, H. L. J . phvs. Chem. 1969, 73. 3934. (18) Kell, G. S. J . them. €ng. Data 1975, 20, 91.
(27) (28)
337
Mega, J.; Paz-Andrade, M. I. J . Chem. €ng. L?ata 1986, 31, 231. Vaslow, F. J . hys. Chem. 1968, 70, 2288. Cowle, J. M. G.; Toporowski, P. M. Can. J . Chem. 1981, 39, 2240. Pruett, D. J.; Feker, L. K. J . Chem. €178.Data 1985, 30, 452. Werblan, L.; Leslnskl, J. Pol. J . Chem. 1978, 52, 1211. Klnert, C. M.; Kinart, W. J.; Skulskl. L. Po/. J . Chem. 1988, 60, 879. Cox, B. 0.;Waghorne, W. E. Chem. Soc. Rev. 1980, 9 , 380. Petrella, 0.; Petrella. M.; Castagnolo, M.; Dell'Atl, A.; De Glgllo, A. J . Sdutlon Chem. 1981, 10, 129. Marcus, Y. J . Chem. Soc.,Faraday Trans. 1 1987, 83, 2985. a n a , R.; Yeager, E. B. In Modem Aspects of € k t " b b y ; Bockrls, J. O'M., Conway, B. E., Whke. R. E., Eds.; Plenum Press: New York, 1982; Vol. 14. pp 1-80. Hlrakawa, H. J . Phys. Chem. 1987, 33, 3452. Marcus, Y. Ion W a t i o n ; Wiley: New York. 1985; Chapter 8.
Received for revlew October 21, 1991. Revlsed March 9, 1992. Accepted March 23, 1992.
Vapor-Liquid Equilibria for Carbon Dioxide
+ I-Pentanoi
Davld W. Jennlngs, Franchot Chang, Vlvlan Bazaan, and Amyn S. Tela* School of Chemical Enginwring, Georgia Institute of Technology, Atlanta, Georgia 30332-0 700
+
Table
Vapor-IlquM qulllbrla have been measured for C02 l-pentanol at 314.6, 325.9, and 337.4 K urlng a hlgh-premure flow apparatus. The pressure In the exporlments ranged from 5.176 to 11.983 MPa. The r u u l k rhow that the phase behavior of C02 l-pentanol k slmllar to the phaw behavior observed for C02 ethanol and CO, l-butanol.
+
+
C02
PI MPa 5.178 6.157 6.902 7.598 8.074
+
Introduction
6.164 6.943 7.667 8.274 8.977 9.660 10.342 10.556
+
This work farms pert of a continuing study of COP akanols ( 7 ) of interest in the extractlon of biomoiecules (2-4) with supercritical COO aikanois, extraction of aikanols from aqueous solutions with carbondioxide (5-8), and the production of aka& from syngas (9). Atthough much attention has been focused on COP methanol and C02 ethanol systems, very iktk attention has been pald to C02 higher aikanoi systems. I n fact, no previous vapor-iiquld equlilbrium measurements have been reported In the literatwe for COP 1-pentanoi with the exception of the critical properties of dilute mixtures measured by Qurdlai et ai. (70).
+
+
+ +
5.585 6.943 7.639 8.294 8.956 9.660 10.418 11.052 11.983
+
Experimental Section The experimental procedure and apparatus have been described in detail previously (7), and only brief details are glven below. Carbon dioxlde from a cylinder and 1-pentanoi from a reservoir were mixed and pumped through a series of miis and static mixers placed inslde a constant-temperature air bath. Vapor-liquid equilibrium was attained durlng the pumping process. After equiiibratlon, the phases were separated in a high-pressure stainless steel view cell (slmllar to a Jerguson level gauge) and each phase was depressurized across a micrometerlng valve. The pentanoi from each phase was condensed and collected in a cold trap, while the carobn dioxide was allowed to pass through a wet test meter. Equilibrium phase compositlons were calculated from the weights of the pentanol collected and the volume of carbon dloxlde measured by the wet test meters. Small corrections were made for the reslduai pentanoi not condensed and for the carbon dioxide dissolved In the condensed pentanoi. Typically, 4-6 liquid samples and 3-5 vapor samples were collected. The reported compositlons represent an average of ail the samples equiil002 1-9508/92/ 1737-0337$03.00/0
I. Experimental Vapor-Liquid Equilibrium Data for
+ I-Pentanol
T/K 314.7 314.8 314.7 314.7 314.3 av: 314.6 325.9 326.0 325.9 326.0 326.0 326.0 325.8 325.9 av: 325.9 337.4 337.3 337.4 337.5 337.4 337.4 337.4 337.4 337.5 av: 337.4
0.3368 0.4135 0.4850 0.5657 0.6714
Yco* 0.9991 0.9989 0.9984 0.9977 0.9969
0.3367 0.4044 0.4612 0.5077 0.5695 0.6433 0.7516 0.7944
0.9983 0.9978 0.9971 0.9965 0.9951 0.9924 0.9781 0.9617
0.2834 0.3583 0.3976 0.4346 0.4767 0.5220 0.5772 0.6300 0.7185
0.9975 0.9969 0.9963 0.9958 0.9949 0.9936 0.9911 0.9876 0.9745
xco* ~~
brated at the deslred pressure and temperature. Additionally, to verify that equilibrium conditions had been attained, some experiments at a given temperature and pressure were repeated at different flow rates. No changes in equilibrium compositions with flow rates were detected. The pressure was measured by a digital Heise pressure gauge (model 710A) which was calibrated against a Budenburg dead weight tester. The pressure measurements were estC mated to be accurate within f0.014 MPa. The temperature was determined by a thermistor inserted into the top slde of the view cell. The thermlstor was callbrated against a Fluke digltai thermometer equipped with a platinum probe (model 2180 A). The temperature measurements were estlmated to be accuate within &O.l K. Both wet test meters were factory callbrated with a stated accuracy of 0.5 % A Sartorius balance, model 1872, was used to measure the weight of alcohol condensate collected. The weight measurements were reproducible within
.
0
1992 American Chemical Society
12-
0
;i 5
0.2
0.3
rl,,
0.5
0.4
,
,
,
I
0
I
,
0.7
0.6
,
0.6
,I
, 0.9
1
MOLE FRACTIONC02 Flguro 1. Vapor-liquid equilibrla for COP -I- 1-pentanol at 337.4 K.
last sample, although this change was less than 0.3 K. The reported temperature is an average of the maximum and minimum temperatures recorded during the sampling period. The reproducibility of the liquid-phase compositlons was usually within f0.001 mole fraction, and that of the vaporphase composbns within f0.0002 mole fraction. The Iquidphase compositions were estimated to be accurate within f0.003, and the vapor-phase compositions within 10.0006. These estimates are based on the accuracy and the precision of the instruments used In measuring the compositlons, the reproducibility of the measurements, and comparisons with measurements of other lnvestlgators made in our earlier work (7). Souoo and pvlly d tho Matenbls. Coleman grads carbon dioxide of purity 99.99% was o b t a M from Matheson Gas Products. l-Pentand was obtained from Albich Chemicals and had a stated purity of 994- % . All substances were used without further purification. Rewits
+
Vapor-liquM equilibrium data for COz 1-pentanoi at 314.6, 325.9, and 337.4 K are presented in Table I. The data at 337.4 K are shown in Figure 1. The data exhibit phase behavior which Is similar to that found for COP ethanol and COz 1-butanol systems in our earlier work. K values (yllxl)for ail three isotherms are shown in Figure 2.
+
+
v)
W
3
0
0.11
!i
0.001
Rogbtry No. COP, 1 2 4 3 8 9 ; 1-pentanol, 71-41-0.
A
3
Literature Cited
D 1
1 4
.e
I
I
6
I
,
D
I
10
8
.
I
12
14
PIMPa Flgwo 2. Kvalues in the C02 4A, 337.4 K.
lpentanol system: 0 , 3 1 4 . 6 K; 0,
325.9 K;
fO.OOO1 g, and the accuracy of the welght measwements was estimated to be within fO.OO1O g. The pressue and temperature were recorded throughout the experiment to determine how “equilibrium conditions” were being mahlned. The preawe fluctuatkns were generaw less than f0.024 MPa during an experiment. On the other hand, the temperatwe generally increased slightly from the first to the
(1) Jennlngs, D. W.; Lee, R. J.; Teja, A. S. J . C h m . Eng. Data 1991, 36, 303. (2) Schaeifer. S. T.; Zalkow, L. H.; Teja, A. S. Fluid Fhase E9uMb. 1988. 43,45. (3) Schaeffer, S. T.; Zalkow, L. H.; Teja, A. S. Blotechnol. Bbeng. 1989. 34, 1357. (4) Wong, J. M.; Johnston, K. P. Blotechnol. Frog. 1986. 2 , 28. (5) Kuk. M. S.; Montagna, J. C. In Cheml%el Engbering at Supwcrlylcel Fluid condwons; Paulaitls, M. E.; Pennlnger, J. M. L., aay, R. D., bidson, P.. E&.; Ann Arbw Sclence: Ann Arbor, MI, 1983 Chapter 4. (6) Gilbert, M. L.; Paulaltts, M. E. J . Chem. Eng. Data 1986, 31, 286. (7) De Fllllpl, R. P.; Moses, J. M. Blotechnol. Bbeng. Symp. 1982, 12, 205. (8) de la Ossa, E. M.; Brandanl, V.; Del Re, 0.; Dl Giecomo, G.; Feni. E. F h M P h a s e E9ulIlb. 1990, 56, 325. (9) Suzukl, K.; Sue, H.; Aral, K.; Salto. S. Fluid a s e EquMb. 1990, 59, 115. (10) Ourdlel,G.S.;Foster,N.R.;Yun,J.S.Rooeedk?gsofIhe2ndInrsrnatlon81 Symposium on SuperwmCal Flu&, Boston, MA, 1991; p 86. Recelved for review December 10, 1991. Accepted March 23, 1992.
