Pervaporation performance of poly (acrylic acid)-poly (vinyl alcohol) blend membrane for separation of methanol-dimethyl carbonate azeotrope

Poly (acrylic acid)-poly (vinyl alcohol) (PAA-PVA) blend membrane was prepared by coating method for separating methanol-dimethyl carbonate (MeOH-DMC) azeotrope by pervaporation, and the influences of mass ratio of PAA to PVA, and heat treatment conditions on pervaporation performance of the membrane were investigated. The experimented results of pervaporation showed that as the heat treatment time and temperature increased, the separation factor of MeOH increased first and then decreased, but the flux decreased gradually, as PAA/PVA ratio increased, the separation factor increased first and then decreased, but the flux decreased first and then increased. For separating MeOH-DMC azeotrope of 70% (ω) MeOH at 70°C, the PAA-PVA blend membrane with a mass ratio of PAA to PVA at 7/3 and heated at 150°C for 60 min had the highest selectivity, the separation factor of MeOH was 9.5 (MeOH in the permeate side of 95.5%, ω), the flux 360 g/(m2·h).