PERVAPORATION OF WATER AND ETHANOL USING A CELLULOSE-ACETATE BUTYRATE MEMBRANE

Okada and Matsuura’s transport equations for pervaporation give rise to three fundamental parameters, namely, interfacial saturation vapor pressure P*, liquid transport parameter A/δ, and vapor transport parameter B/δ. The effects of the chemical nature of the membrane material and the upstream operating pressures of 101.3 and 303.9 kPa on the above parameters were investigated from the pervaporation data at laboratory temperature (24°C) for water and ethanol using a cellulose acetate butyrate membrane. The results show that the P*, values are essentially unaffected by the upstream pressure, and that they are generally higher than the literature values of saturation vapor pressure at 24°C. Further, the values for A/δ and B/δ tend to increase with increased upstream pressure for both systems studied. These results are discussed. © 1993 by Academic Press, Inc.