Facile synthesis of ethylenediamine-modified magnetic chitosan composite and its adsorption property

In this study, ethylenediamine-modified magnetic chitosan composite (MCS-NH2) adsorbent was synthesized facilely by one-pot method. The structural analysis of the composite were obtained from Fourier-transform infrared, X-ray powder diffraction, thermogravimetric analysis, vibrating sample magnetometer, scanning electron microscopy, field transmission electron microscopy, zeta potential, Brunauer-Emmett-Teller specific surface areas, and pore structure. Its adsorption capacities toward anionic dye Orange II (ORII) were studied in a batch system. The highest ORII removal of 94.3% was obtained at the optimum conditions: pH 7.07, initial ORII concentration 100 mg L-1, adsorbent dose 3 g L-1, and room temperature (293 K) at 30 min. In addition, the effect of various salts on the adsorption performance of MCS-NH2 was also investigated. The kinetic adsorption isotherms and thermodynamics were also studied and the experimental data fitted better with the pseudo-second-order kinetic and the Freundlich model, with spontaneous and exothermic characteristics. The results showed that MCS-NH2 composite exhibited excellent adsorption capacities toward anionic dye, which should have potential applications in effluent treatment in printing and dyeing industry.