Preparation of chitosan/organoclay nanocomposite as silver(I) ion adsorbent

Abstract

Different molecular weight chitosans were prepared by the depolymerization of commercial chitosan with hydrogen peroxide. The depolymerized chitosans were used to modify montmorillonite to provide organoclay. The chitosan/oraganoclay nanocomposite beads were evaluated as an adsorbent of Ag(I) ion. Batch adsorption experiments were performed as a function contact time, organoclay concentration, pH and adsorbent dosage. Isotherm analysis showed that the adsorption pattern of Ag(I) ion onto nanocomposite followed well the Langmuir model. Using the Langmuir model equation, the maximum adsorption capacity of nanocomposite bead was found 80.39 mg g-1. The pseudo-second order equation described best kinetic data of Ag(I) ion. The Ag(I) ion desorption of nanocomposite bead was 9.68 % at pH 4. SEM/EDX images confirm that after adsorption the Ag(I) ions were dispersed onto the nanocomposite bead surface. This study demonstrated that the chitosan/organoclay nanocomposite can effectively remove Ag(I) ion from aqueous solution. © 2017, Chemical Publishing Co. All rights reserved.