Reverse osmosis separations of some organic and inorganic solutes in ethanol solutions with cellulose acetate membranes

Abstract

Reverse osmosis (RO) separations of inorganic and organic solutes from ethanol solutions were studied in this paper. Together with the retention volume data from liquid chromatography (LC) experiments, RO separation data can be used to determine the interfacial interaction force constants which characterize steric, van der Waals, and electrostatic forces working on solutes at the membrane material-ethanol interface. The above constants allow us to predict the membrane performance data together with the pore radius of the membrane surface. The RO separations from ethanol solvent were compared with those from methanol and water solvents. It was found that the membrane performance data were closely related to the preferential sorption characteristics of solutes in different solvent environments.