Removal of methyl orange from aqueous solutions by adsorption using chitosan intercalated montmorillonite

Abstract

Adsorption of methyl orange (MO) using a montmorillonite modified with chitosan has been investigated. Thecharacteristics of montmorillonite and chitosan intercalated montmorillonite (CTS/MMT) were examined by means of SEMand BET-analysis. The effects of operating parameters such as contact time, initial solution pH, initial dye concentration, andtemperature on the adsorption of MO were also studied. The results revealed that adsorption of MO was initially rapid andthe equilibrium time was reached after 1 hr. Adsorption kinetics were best described by the pseudo-second order model. Anaqueous solution with a pH of 2.0 was favorable for the adsorption. The equilibrium data were better fitted by Langmuirisotherm compared to the Freundlich isotherm. The adsorption of MO increased with operating temperatures indicating anendothermic process. Reutilization of the bio-composite was feasible. These results suggested that the CTS/MMT can beused as an adsorbent for removal of MO from aqueous solutions.

Keywords

• adsorption
• chitosan intercalated montmorillonite
• intercalation
• methyl orange
• desorption