Effective removal of copper from aqueous solutions by modified magnetic chitosan/graphene oxide nanocomposites

摘要

In the present work, a novel magnetic chitosan/graphene oxide nanocomposite (MCGON) was synthesized for the removal of Cu2+ from aqueous solutions. The adsorbent was composed of graphene oxide (GO) modified by ethylenediamine (ED), Fe3O4 nanoparticles and chitosan-g-poly(acrylic acid-co-2-acrylamido-2-methylpropane sulfonic acid) copolymer. The composition and structure of adsorbents were characterized by FTIR, SEM, EDX, XRD, TGA, VSM and BET analysis. The magnetic MCGON with a high specific surface area of (132.9 m(2) g(-1)), large pore volume (4.03 cm(3) g(-1)), small particle size (15 nm) and strong saturation magnetization (3.82 emu g(-1)) was used as an efficient adsorbent for the removal of Cu2+ ions from wastewater. The results showed that the adsorption of Cu2+ onto MCGON exhibited a maximum adsorption capacity of 217.4 mg g(-1). Kinetics, thermodynamics and equilibrium isotherm of the removal of copper (II) ions were carefully investigated. Adsorption of Cu2+ onto nanocomposite followed pseudo-second-order and Langmuir isotherm models. Thermodynamic parameters exhibited that the sorption process was feasible, spontaneous and endothermic in nature. These results provide evidences for the efficient removal of heavy metals from industrial wastewater. (C) 2018 Elsevier B.V. All rights reserved.