Colloid–membrane interaction effects on flux decline during cross-flow ultrafiltration of colloidal silica on semi-ceramic membranes

摘要: In order to investigate colloid–colloid, as well colloid–membrane interaction effects on the flux decline occurring during membrane processes, filtration tests were performed at different electrolyte concentrations, pH values. The surface properties of colloidal silica particles determined by electrophoretic light scattering, whereas charge characteristics ultrafiltration membranes derived from streaming potential measurements. From versus transmembrane pressure curves, it was that both high and low salt concentrations preferable optimise permeate provided had similar characteristics. At concentration, this behaviour due colloid–colloid repulsive interactions, which largely reduced concentration polarisation. flocculation dispersions gave raise large, porous flocs. As a consequence latter effect, concentration–polarisation layer became highly permeable. On other hand, severe observed conditions where oppositely charged, giving rise attractive electrostatic interactions. results indicate performance is strongly affected its with in feed. Optimum are obtained if interactions prevail, may be accomplished proper conditioning