Porosity of some commercial reverse osmosis and nanofiltration polyamide thin-film composite membranes

The objective of this study was to determine porosity parameters of some commercial polyamide thin-film composite membranes, and to explain their influence on membrane performance. Experiments were performed at two operating pressures using model inorganic and organic aqueous solutions. Pore size distributions and the effective number of pores in the upper membrane layer were calculated from the experimental results. The performances of the examined membranes were explained using the calculated porosity parameters. (C) 2000 Elsevier Science B.V. All rights reserved.