Adsorption of naphthalene and its derivatives on magnetic graphene composites and the mechanism investigation

Reduced graphene oxide/iron oxide (GO/FeOFe2O3) composites were prepared as super adsorbent to adsorb 1-naphthylamine, 1-naphthol and naphthalene with different polaritiy. The adsorption capacity was found in the order of naphthalene < 1-naphthol < 1-naphthylamine. Electron-donor–acceptor (EDA) interaction was proposed to be the primary mechanism for the adsorption of aromatic compounds, and the adsorption capacity increased with increasing dipole moment. Compared with multi-walled carbon nanotubes/iron oxide (MWCNTs/FeOFe2O3), we found the morphology of adsorbents played an important role in the adsorption for these aromatic compounds. Thermodynamic experiments further indicated that the adsorption processes were endothermic and spontaneous.