Adsorption of an anionic azo dye by chitosan/kaolin/gamma-Fe2O3 composites

Chitosan/kaolin/nanosized gamma-Fe2O3 composites were prepared by a microemulsion process and characterized by TEM, SEM and WAXRD. Many pores and pleats were visible on the surface of the composites and provided a good condition for dye adsorption. Methyl orange (MO) was selected as a model anionic azo dye to examine the adsorption behavior of the composites. Amounts of 71.0% of MO were adsorbed within 180 min from 20 mgL(-1) MO solution at pH = 6.0 by 1.0 g L-1 adsorbent dosage. Therefore, the composites can be used as a low-cost alternative for anionic dyes removal from industrial wastewater. (C) 2010 Elsevier B.V. All rights reserved.