ABSTRACT
The shortage of freshwater has been a serious problem in the world due to the increase in population and the contamination of fresh water resources. There is an increasing demand for producing potable water by treating ground, surface and seawater. Electrodialysis (ED) is one of the useful methods to make drinking water from surface water or groundwater. ED is an electrochemical desalination process that utilizes the ion permselectivity of cation and anion exchange membranes. This chapter reviews the improvement of antifouling property and monovalent anion selectivity of anion exchange membranes by surface modification, mainly by layer-by-layer (LbL) deposition. It also reviews the mechanism of LbL multilayer formation and the effect of polyelectrolyte layer on surface properties. The chapter shows the effect of polyelectrolyte layer on the antifouling property and the monovalent anion selectivity including the mechanism. The multilayer is formed by alternately dipping a membrane into a polyelectrolyte solution with an opposite charge.
