A cleaning method for anion exchange membrane fouled by sodium polyacrylate

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.