[en] The influence of the total downstream pressure on the pervaporation flux of a pure compound through a dense polymer membrane has been the subject to controversial debates recently. Experimental arguments in favor of either the solution−diffusion model or the newly proposed pore-flow model are alternatively reported on different systems. To critically reexamine this debate, an experimental study under controlled downstream conditions has been performed for pure methanol and pure 2-propanol pervaporation through a poly(dimethylsiloxane) film, the latter having been previously reported to follow pore-flow model predictions. It is shown that a rational analysis of the effects of the downstream pressure on the results can be achieved according to the classical solution−diffusion model, provided that the influence of air leaks in the installation is properly taken into account. Based on this observation, the implications of an inert gas contribution, generally speaking, on pervaporation operation are discussed.
Disciplines :
Chemical engineering
Author, co-author :
Vallières, Cécile; Groupe ENSIC > LCPM, CNRS UMR 7568
Favre, Eric; Groupe ENSIC > LSGC, CNRS UPR 6811
Roizard, Denis; Groupe ENSIC > LCPM, CNRS UMR 7568
Bindelle, Jérôme ; Université Catholique de Louvain - UCL > Unité des Procédés
Sacco, Daniel; Groupe ENSIC > LCPM, CNRS UMR 7568
Language :
English
Title :
New Insights into Pervaporation Mass Transport under Increasing Downstream Pressure Conditions: Critical Role of Inert Gas Entrance.
Feng X., Huang R.Y.M. (1997) Liquid separation by membrane pervaporation: A review. Ind. Eng. Chem. Res. 36:1048.
Paul D.R. (1976) The solution - Diffusion model for swollen membranes. Sep. Purif Methods 5:33.
Wijmans J.G., Baker R.W. (1995) The solution - Diffusion model: A review. J. Membr. Sci. 107:1.
Lee C.H. (1975) Theory of reverse osmosis and some other membrane permeation operations. J. Appl. Polym. Sci. 19:83.
Okada T., Matsuura T. (1991) A new transport model for pervaporation. J. Membr. Sci. 59:133.
Vetter A.F., Kim S.N. (1967) Liquid permeation of 2-propanol and water in a silicone rubber. Sep. Sci. 2(5):625.
Yoshikawa M., Matsuura T., Cooney D. (1991) Studies on the state of permeant in the membrane and its effect on pervaporation phenomena. J. Appl. Polym. Sci. 42:1417.
Wessling M., Werner U., Hwang S.T. (1991) Pervaporation of C8-isomers. J. Membr. Sci. 57:257.
Bai J., Fouda E., Matsuura T. (1994) Effect of upstream pressure on the flux of single permeant in pervaporation. Polym. J. 10:1100.
Wu W.S., Lau W.W.Y., Rangaiah G.P., Sourirajan S. (1993) Pervaporation of water and ethanol using a cellulose acetate butyrate membrane. J. Colloid Interface Sci. 160:502.
Greenlaw F.W., Prince W.D., Shelden R.A., Thompson E.V. (1977) Dependence of diffusive permeation rates on upstream and downstream pressures. J. Membr. Sci. 2:141.
Paul D.R., Paciotti J.D. (1975) Driving force for hydraulic and pervaporative transport in homogeneous membranes. J. Polym. Sci., Polym. Phys. 13:1201.
Néel J. (1991) Introduction to pervaporation. Pervaporation Membranes Separation Processes, Huang, R. Y. M., Ed., Elsevier Science Publishers: Amsterdam; .
Néel J., Nguyen Q.T., Clément R., Lin D.J. (1986) Influence of downstream pressure on the pervaporation of water - Tetrahydrofuran mixtures through a regenerated cellulose membrane (cuprophan). J. Membr. Sci. 27:217.
Kataoka T., Tsuru T., Nakao S., Kimura S. (1991) Permeation equations developed for prediction of membrane performances in pervaporation, vapor permeation and reverse osmosis, based on the solution - Diffusion model. J. Chem. Eng. Jpn. 24:326.
Barrie J.A. (1966) Diffusion of methanol in poly(dimethylsiloxane). J. Polym. Sci. A 4:3081.
Nii S., Mao Z.G., Takeuchi H. (1994) Pervaporation with sweeping gas in polymeric hollow fiber membrane module. Separation of alcohols from aqueous solutions. J. Membr. Sci. 93:245.
