离子交换膜改性的研究现状及发展趋势

Present status and development trend of modification of ion-exchange membranes

离子交换膜已广泛应用于化工、废水治理等工业领域。但是,目前所使用的离子交换膜选择透过性低、机械强度差、抗污染能力弱,对离子交换膜进行改性可以改善这些性能。综述了离子交换膜的改性方法,包括组成改性(表面改性和掺杂改性)和结构改性(中空纤维结构改性和增加膜基质孔隙率改性)。通过对这些方法进行分析对比得出:表面改性和掺杂改性,以聚合物为添加剂,技术简单、易操作,并且能够提高膜的综合性能,是膜改性的重要发展方向;中空纤维结构改性,由于膜的使用条件严格、清洗困难,目前得不到广泛应用,但是中空纤维结构改性使膜的结构从根本上发生了改变,这是膜改性的一个重要途径;增加膜的孔隙率只适合多孔膜的改性,这种方法研究较少。

Ion exchange membranes have been widely used in various industrial fields,such as chemical industry and waste water treatment.The current ion exchange membranes have the disadvantages of low permselectivity,poor mechanical strength,and weak anti-pollution ability.The modified ion-exchange membranes can overcome the above shortcomings.The modified methods of ion exchange membrane including the compositional modification（the modifications of surface and doping） and structural modification（the modifications of the structure of hollow fibers and the membrane porosity increase） were summarized.Comparative analysis indicated that the surface and doping modifications using polymer as additive become an important development trend of membrane modification owing to simple technique and easy operation as well as being able to improve the comprehensive performance,while the modification of the structure of hollow fibers has not been widely applied due to the strict application conditions and difficult to clean.However,as the modification of the structure of hollow fibers makes the membrane structure fundamentally change,it is a critical approach of membrane modification.The membrane porosity increase is only suitable for the modification of porous membrane,therefore,there is few research on this method.