連続加圧法による精密ろ過膜の流動電位測定法の開発

抄録

The continuous pressure increasing method to measure streaming potential for microfiltration membrane was developed. In this study the streaming potential, SP, was defined as the trans-membrane electrical potential difference ΔE_TM per unit trans-membrane pressure difference ΔP_TM. This developed method has a feature to measure the SP precisely in a short time with a small amount of measuring solution in spite of using unstable electrode material as compared with the conventional step method. The effects of pressure increasing rate, the time range for data processing, and kinds of electrode materials on the linearity between P_TM and E_TM, which is an index of accuracy of measurement, were examined using cellulose acetate membrane and KCl solution. The availability of developed method was confirmed by comparing with the results obtained by conventional step method. The coefficient of variation of SP measured by repeating measurement was less than 5%. The kinds of electrodes material didn't affect the measurement results. And it was demonstrated that the dependence of SP on electrolyte concentration could be continuously measured by combining with the continuous increasing method of KCl concentration of the measuring solution.