Abstract
Chitosan is a polysaccharide formed mainly from repeating residues of D-glucosamine, having primary amino groups. It is of great interest not only as an underutilized resource, but also as a new functional material of high potential in various fields, and recent progress in chitin chemistry is quite noteworthy. The purpose of this review is to take a closer look at chitosan application in water technology based on (a) its ability to bind toxic pollutants, (b) the mod of chitosan modification, (c) the nature of the interaction of chitosan with different pollutants, and (d) chitosan regeneration and recycling.