Environmental application of amine functionalised magnetite nanoparticles grafted graphene oxide chelants.

Abstract

This study proposed a two-step method involving hydrothermal and electrostatic self-assembly processes for synthesising an amine-functionalised magnetic ligand graphene oxide-based nanocomposite (EDTA@Fe3O4@GO). The amine groups were successfully attached to the surface of iron (II, III) oxide (Fe3O4), which were embedded on the surface of graphene oxide (GO) (Fe3O4@GO). This EDTA@ Fe3O4@GO nanocomposite was used as a chelating agent to bind the toxic heavy metal ions. EDTA@Fe3O4@GO demonstrated the synergistic effect between the large surface area and magnetic behaviour of Fe3O4@GO and the chelating effect of EDTA, and it showed higher efficiency than the individual GO and Fe3O4. The possible structural and compositional characteristics were proposed based on Fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer-Emmett-Teller (BET) and Raman spectroscopy analysis. The outcomes revealed the mechanism behind the excellent As(V) adsorption onto EDTA@Fe3O4@GO. The adsorption process was studied by fitting the experimental data obtained into various kinetic and isotherm models. The pseudo-second-order (PSO) kinetic model and the Freundlich isotherm model (FIM) were found to be the best fit models for the removal of As(V) by EDTA@Fe3O4@GO. EDTA@Fe3O4@GO has the utmost adsorption capacity of 178.4mg/g. Furthermore, the EDTA@Fe3O4@GO nanocomposite is reusable, and it showed excellent adsorption capacity up to 5 cycles. This study has provided insight into the potential of EDTA@Fe3O4@GO and its applications in large-scale wastewater treatment.