Characterization of polysulfone hollow-fiber ultrafiltration membrane and its cleaning efficiency by streaming potential and flux method

Abstract

Polysulfone (PS) hollow-fiber ultrafiltration membrane was characterized combined with flux and streaming potential in single
electrolyte solutions. The effects of trans-membrane pressure, electrolyte concentration, ion valence and pH value of electrolyte
solution on the streaming potential (SP) of the membrane were investigated. The zeta potential and surface charge density
of the membrane were calculated on the basis of Helmholtz-Smoluchowski equation and Gouy-Chapmann theory. The results indicate
that the valence and concentration of cation have a greater influence on the SP and surface charge density of PS membrane
than those of anion, and the pH value of electrolyte solution has great effects on the SP and zeta potential of the membrane
surface. Both the absolute value of the streaming potential and water flux of the adsorbed membrane decrease, compared with
those of the clean membrane. The streaming potential and flux of the cleaned membrane can be completely recovered by cleaning
with the mass fraction of 0.8% EDTA at pH=10.