聚偏氟乙烯中空纤维膜污染过程中动电现象的研究

Electrokinetic behavior during the fouling process of PVDF hollow fiber membrane

通过自行研制的一套中空纤维膜的流动电位测定装置,对聚偏氟乙烯（PVDF）中空纤维微滤膜的动电现象和过滤通量进行了研究.结果表明,PVDF膜的等电点（IEP）为3.4,在一般水质条件下荷微弱正电,在0.01 mol/L的KCl溶液中Zeta电位仅为0.3-0.5 mV.在牛血清蛋白（BSA）溶液过滤过程中,流动电位为正值,随时间延长逐渐下降;在乳化油废水过滤过程中流动电位为正,随时间升高并逐渐达稳定.

In this paper,a self-made experimental apparatus was used to measure the streaming potential of PVDF hollow fiber microfiltration membrane.The electrokinetic behavior and the flux of the hollow fiber membrane were investigated.The experiment results indicated that the isoelectric point（IEP） of PVDF membrane was 3.4.The Zeta potential was at the range of 0.3-0.5 mV in 0.01 mol/L KCl solution,which suggested that the PVDF membrane possessed weak positive charges.During the filtration of bovine serum albumin（BSA） solution,the streaming potential with a positive value decreased over time.In the case of emulsified oil wastewater filtration,it was noted that the streaming potential increased and in turn reached a relatively stabile value.