Removal of Mo(VI) as oxoanions from aqueous solutions using chemically modified magnetic chitosan resins

Abstract

Chitosan was cross-linked using glutaraldehyde in the presence of magnetite. The resin obtained was chemically modified through the reaction with tetraethylenepentamine followed by glycidyl trimethylammonium chloride to produce chitosan bearing amine (R1) and chitosan bearing both amine and quaternary ammonium chloride moieties (R2), respectively. The removal of Mo(VI) as molybdate anions from aqueous solution was studied using batch and column methods. R1 works efficiently towards the removal of molybdate in acidic medium. Whilst R2 works efficiently in all pH ranges (acidic/neutral/basic). The nature of interaction of the resins obtained with molybdate was clarified. The resins showed a higher affinity towards the uptake of Mo(VI). Kinetics and thermodynamic parameters of the uptake process were obtained. Breakthrough and regeneration curves for the removal of Mo(VI) were also studied. The adsorbed molybdate anions were found to be effectively eluted from the investigated resins.