Electrokinetic behavior of membrane zeta potential during the filtration of colloidal suspensions

A study of the membrane zeta potential determined by the streaming potential was made to investigate the electrokinetic characterization as well as the monitoring for cake deposition on the surfaces of a filtration membrane. The membrane zeta potential related to the surface charge characteristics was determined for both flat-plate and hollowfiber cases. In this study, we showed successfully that changes in membrane zeta potential could be used to investigate the behavior of cake deposition and fouling during the filtration of colloids. With the simultaneous monitoring for fully retentive membranes, it is found that both the permeate flux and the membrane zeta potential are decreased as the latex concentration increases. Since the development of cake layer is dependent on axial positions in the hollow-fiber membrane, the difference of zeta potential with respect to inlet and outlet positions has been observed.

the charge characteristics of the pore surface for flat-plate as well as hollow-fiber membranes were investigated by applying the Helmholtz– Smoluchowski principle. We observed the development of a cake layer with full retention and the particle adsorption with partial retention during the time progress of filtration where the axial position-dependent zeta potential of the hollow fiber was significantly considered.