Chapter 3 - Chitosan/poly(vinyl alcohol) modified adsorbents for the removal of heavy metals from wastewaters

Abstract

Scientific efforts in wastewater treatment have resulted in a large diversity of sorbents, ranging from low-cost to expensive ones, that have been applied to various liquid-phase pollutants, such as heavy metals and dyes, in single, binary, and multisolutions, as well as to real industrial wastewaters. This chapter introduces the reader to the properties, functions, and modifications of composite sorbents based on chitosan (Cs) and poly(vinyl alcohol) that are applied to the treatment of heavy metals. Interesting results have been reported for these sorbents either in film or bead form, being cross-linked or not; their modification involves techniques ranging from simple techniques such as addition of magnetic nanoparticles to more intellective ones such as ion imprinting. The regenerative ability of the sorbent provides for experimentation and further improvements, while the combination of a well-known biosorbent for its adsorptive properties with a low-cost biodegradable synthetic polymer triggers the eco-friendly profile of the environmentalists and boosts the relative industries for green investments.