STREAMING POTENTIAL AND ION TRANSMISSION DURING ULTRAFILTRATION AND MICROFILTRATION ON INORGANIC MEMBRANES

The streaming potential, permeate flux and ion transmission are measur ed on inorganic ultra-and microfiltration membranes. The streaming pot ential depends on charge distribution, which is modified by changing t he pH, the ionic strength, and the nature of ions. The study reveals t hat it is indispensable for characterizing the membrane state from a c harge point of view. Moreover, the ion transmission and pH variations between retentate and permeate are correlated to the membrane net char ge, quantified by streaming potential values. The influence of membran e pore radius on streaming potential measurements and on apparent zeta potential values are analyzed in relation with the double layer overl apping. This study points out the effect of membrane net charge on ion transmission even in the case of a very large pore radius as for micr ofiltration membranes.