Plasma deposition of acrylamide onto novel aromatic polyamide membrane forpervaporation

Pervaporation of water/ethanol mixtures through acrylamide-plasma graft-aro matic polyamide, AAm-p-aramide, an aramide membrane on which AAm is grafted by plasma polymerization. was investigated in this work. The surface prope rties of the AAm-p-aramide membranes were characterized by atomic force mic roscopy, AFM, and contact angle meter. The effects of degree of grafting, f eed composition, feed temperature and surface properties on the pervaporati on performances were studied. The separation factor and permeation rate of the AAm-p-aramide membranes were higher than that of the unmodified aramide membrane. Optimum pervaporation was obtained by a AAm-p-aramide membrane w ith a degree of grafting of 20.5% for a 90 wt% ethanol feed concentration, giving a separation factor of 200 and a permeation rate of 325 g/m(2)h. (C) 2000 Elsevier Science Ltd. All rights reserved.