Enhancement of Adsorption Capacity of Chitosan by Chemical Modification

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Enhancement of Adsorption Capacity of Chitosan by Chemical Modification

Olalekan C. Olatunde, Chidinma G. Ugwuja, Emmanuel I. Unuabonah

Chitosan is a natural biopolymer which has found wide application in fields like medicine, drug delivery and water purification due to its unique chemical and physical properties. Being the second most abundant natural polysaccharide on earth, application of Chitosan for adsorption of pollutants is gaining wide acceptance due to many possible derivatives and properties of Chitosan that can be explored. However, despite its excellent properties, the use of chitosan for adsorption purposes is limited by its poor mechanical property and solubility especially in acidic medium. These limitations could, however, be offset by modifying Chitosan via various chemical routes like the grafting of – sulfur (S), oxygen (O), nitrogen (N) and phosphorus (P) – containing functional moieties and crosslinking reagents. Studies into the mechanism of adsorption of these modified Chitosan materials showed great dependence on pH and on the nature of the incorporated functional group, with chelate formation and electrostatic interaction being the most prominent adsorbent-adsorbate interaction. This chapter seeks to provide an in-depth review on some of these chemical modifications as well as current trends in the engineering of Chitosan for efficient water treatment.

Keywords
Chitosan, Adsorption, Grafting, Crosslinking, Chelate Formation, Electrostatic Interation

Published online 7/1/2018, 42 pages

DOI: http://dx.doi.org/10.21741/9781945291753-8

Part of the book on Chitosan-Based Adsorbents for Wastewater Treatment

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