An insight on kinetic adsorption of Congo red dye from aqueous solution using magnetic chitosan based composites as adsorbent

DOI: 10.22631/chemm.2017.95949.1007 In the present research, a series of magnetic chitosan based composites with the general formula of NixMn1−xFe2O4/CS were synthesized from spinel type transition metal ferrites [NixMn1−xFe2O4 (where x= 0, 0.2, 0.5 and 1.0)] and chitosan (CS) as a polymer. The structure and composition of the synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The adsorption activity of the synthesized magnetic chitosan based composites was evaluated at different contact time, initial dye concentration and temperature for the removal of Congo red (CR) dye from aqueous solution. Furthermore, the influence of the Mn content on adsorption capacity of the synthesized magnetic chitosan based composites were studied. The results of adsorption kinetic of CR dye using spinel type transition metals NixMn1−xFe2O4 and NixMn1−xFe2O4/CS followed pseudo second-order model. The experimental results showed that high percentage of CR dye removal was observed by Ni0.5Mn0.5Fe2O4/CS sample after 180 min. The adsorption performance shows that the chitosan based composites can be more efficient than spinel type transition metals for removal of CR dye. Moreover, the magnetic chitosan based composites can be quickly separated from the aqueous solution by an external magnet after adsorption process.