聚丙烯酸钠污染阴离子交换膜的清洗方法

A cleaning method for anion exchange membrane fouled by sodium polyacrylate

聚丙烯酸钠对阴离子交换膜的污染是影响双极膜电渗析回收丙烯酸丁酯废水中有机酸的关键因素之一。针对该问题研究开发了聚丙烯酸钠污染后离子交换膜的清洗方法,并采用膜电阻、迁移数、表面X射线光电子谱(XPS)分析等对膜清洗效果进行了表征。NaOH、NaCl和HCl溶液3种清洗液对离子交换膜的机械清洗及超声强化清洗效果表明,HCl溶液对聚丙烯酸钠污染阴离子交换膜的清洗效果最好,超声波可促进NaOH、NaCl和HCl溶液的清洗效果。采用2.0 mol L的HCl溶液对受污染阴离子交换膜进行超声清洗,其膜电阻和迁移数可基本恢复到未污染膜的水平。

Anion exchange membrane fouling caused by sodium polyacrylate(PAS)is one of the critical factors that affect organic acid recovery from butyl acrylate wastewater through bipolar membrane electrodialysis.To address this problem,a cleaning method for PAS-fouled anion exchange membrane was developed.The cleaning efficiency of PAS-fouled membrane was evaluated by analysis of membrane resistance,transference number and X-ray photo-electronic spectroscopy(XPS).The cleaning performances with three different cleaning solutions(sodium hydroxide,sodium chloride,and hydrochloric acid)and ultrasonic enhanced cleaning indicated that hydrochloric acid had the best cleaning performance,and the ultrasound could enhance the cleaning effect of all the three solutions.The membrane resistance and transference number of the fouled anion exchange membrane could almost be restored to the same level as uncontaminated membrane when using ultrasound-enhanced cleaning process with 2.0 mol L hydrochloric acid as cleaning solution.