REVERSE-OSMOSIS PERFORMANCE OF MODIFIED POLYVINYL-ALCOHOL THIN-FILM COMPOSITE MEMBRANES

Membrane separation characteristics in the nanofiltration (NF) and rev erse osmosis (RO) regions of the filtration spectrum are governed by a complex combination of both steric hindrance and surface force intera ctions. NF and RO membranes having surface charges show unusual select ivity behavior not predicted on the basis of physical pore size alone. Hence, practical characterizations should employ techniques to gain i nsight on membrane function. In this work, the separation characterist ics of an anionically charged modified polyvinyl alcohol (PVA) thin-fi lm composite membrane under different operating pressures were investi gated. A qualitative measurement of the surface force interactions bet ween solutes and membrane polymer was conducted using liquid chromatog raphy technique. An attempt was also made to study the chlorine resist ance of the composite membrane. (C) 1994 Academic Press, Inc.