Synthesis and application of chitosan/graphene oxide/magnetite nanostructured composite for Fe(III) removal from aqueous solution

Abstract

In this work, we have proposed a method for synthesis of chitosan/Fe3O4/graphene oxide (CS/Fe3O4/GO) nanocomposite and its application for efficient removal of Fe(lII) ions from aqueous solutions. For this purpose, first, graphene oxide (GO) was prepared from graphite by Hummer's method, then, after CS/Fe3O4/GO was synthesized via chemical co-precipitation method from a mixture solution of GO, Fe3+,Fe2+ and chitosan. The synthesized GO and CS/Fe3O4/GO were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), vibrating sample magnetometer (VSM), dynamic light scattering (DLS) and measuring zeta potential techniques. Optimized adsorption conditions for Fe3+ removal such as pH and contact time were investigated. Fe(III) adsorption equilibrium data were fitted well to the Langmuir isotherm and the maximum monolayer capacity (qmax), was calculated as of 6.5 mg.g-1. In addition, the recoverable and recyclable of CS/Fe3O4/GO nanocomposite has been investigated. Data showed that after 6 adsorption-regeneration cycles, the Fe3+ removal efficiency of CS/Fe3O4/GO was still higher than 60%. The results indicated CS/Fe3O4/GO nanocomposite can be used as a cheap and efficient adsorbent for removal of heavy metal ions from aqueous solutions.