Highly efficient adsorption and removal of Chrysoidine Y from aqueous solution by magnetic graphene oxide nanocomposite

Abstract

A new kind of adsorbent graphene oxide nanocomposite (GO–Fe3O4) for removal of Chrysoidine Y was synthesized using the modified Hummers method and co-precipitation. The synthesized GO–Fe3O4 was used as an adsorbent for the removal of Chrysoidine Y from aqueous solution. The effect of initial pH on the adsorption of Chrysoidine Y onto GO–Fe3O4 has been investigated. The adsorption kinetics, isotherm and thermodynamics also have been evaluated. The adsorption was strongly dependent on the pH of medium. The studies on the adsorption revealed that the adsorption process obeyed the Pseudo-second order kinetics model, and the rate-limiting step might be chemical sorption. And the Langmuir isotherm was applicable to describe the adsorption process. This hybrid showed a good performance for the removal of Chrysoidine Y from aqueous solution with an adsorption capacity of 344.83 mg g−1 at room temperature, and could be easily removed from solution using a hand-held magnet in 10 min. Moreover, the adsorption mechanism was discussed and thermodynamic parameters were determined. Thermodynamic parameters indicated that the adsorption process was exothermic and spontaneous. Above all, the removal efficiency of GO–Fe3O4 was still kept at 96.0% when the concentration of dye was 100 mg L−1 in polluted river. This work shows that GO–Fe3O4 is a suitable and efficient adsorbent in the removal of Chrysoidine Y from aqueous solution. Keywords: Adsorption, Chrysoidine Y, Magnetic graphene oxide nanocomposite, Magnetic separation, Removal