Pervaporation(PV) is a technique that consists of sorption, diffusion and evaporation. Dense crosslinked poly(vinyl alcohol)(PVA) membranes of different degree of hydrolysis were prepared and studied in sorption and pervaporation of water-2-propanol mixtures. High selectivities for water were obtained with all type of membranes. Sorption rate of pure water and equilibrium sorption of mixtures increased with the increment of temperature but decreased with the increase of degree of hydrolysis of PVA. Partial flux of water Permeation increases linearly with the water content in the liquid mixture and partial flux of 2-propanol has a maximum point at 40 wt% IPA. Permeation flux and selectivity depend strongly on the degree of hydrolysis of PVA and the temperature of system. A mathematical model for the permeation of liquid mixtures through polymeric membranes taking into account the coupling of fluxes has been developed. The free volume parameter of Fujita's free volume theory was modified in this study.
