PREFERENTIAL SORPTION AND PERMEATION OF BINARY-LIQUID MIXTURES IN POLY(VINYL CHLORIDE) MEMBRANE BY PERVAPORATION

Preferential sorptions and pervaporation selectivities in poly (vinyl chloride) (PVC) membrane for various binary liquid mixtures were investigated. Methanol/n-propanol, benzene/ n-hexane, and ethanol/water mixtures were selected as the binary liquid mixture. In the methanol/n-propanol mixture, methanol was preferentially sorbed in the PVC membrane and predominantly permeated. In the benzene/n-hexane mixture, benzene was incorporated and permeated preferentially. In the ethanol/water mixture, ethanol was preferentially sorbed in the PVC membrane and water was preferentially permeated. The preferential sorptions were analyzed according to Mulder's model derived from Flory-Huggins thermodynamics. The pervaporation selectivity in these systems were discussed using a sorption selectivity and diffusion selectivity. (C) 1995 John Wiley and Sons, Inc.