Sorption and permeation of binary water-alcohol systems through PVA membranes crosslinked with multifunctional crosslinking agents

Sorption and permeation of aqueous alcohol (C-1-C-4) through PVA membrane cross-linked with a multifunctional cross-linker is reported. The effect of temperature, feed concentration, cross-linker loading and the shape and size of the permeating species on pervaporation characteristics is investigated. Sorption isotherms of cross-linked PVA are obtained for the aqueous alcohol systems namely water-methanol, +ethanol, +n-propanol, +isopropanol, +n-butanol and +isobutanol. Values of activation energy for permeation (Delta E-p), diffusion (Delta E-d) and heat of sorption (Delta H-s) for water through cross-linked PVA are estimated. The value of Delta E-d for water was found to vary for all the water-alcohol systems (20-50 kJ mole(-1)) covered in this work. (C) 1997 Elsevier Science B.V.