| Abstract: | A hydrophilic pervaporation membrane was prepared via a homografting polymerization of N,N′-(dimethylamino)ethyl methacrylate (DMAEM) onto nylon 4 backbone, DMAEM-g-N4. The water permselectivity was improved by the ammonium quaterization of the pendant N,N′-dimethylamino group on the DMAEM-g-N4 membrane using demethyl sulfate, DMAEMQ-g-N4. The separation factor and permeation rate for both chemically modified nylon 4 membranes were higher than those of the unmodified nylon 4 membrane. The effects of feed composition, feed temperature, and molar volume of the alcohols on pervaporation performance were investigated. Optimum pervaporation was obtained by a DMAEMQ-g-N4 membrane with a degree of grafting of 12.7% for a 90 wt % ethanol feed concentration, giving a separation factor of 36 and a permeation rate of 564 g/m2h. © 1995 John Wiley & Sons, Inc. |
