Magnetite decorated graphene oxide for the highly efficient immobilization of Eu(III) from aqueous solution

In this paper, a novel adsorbent namely magnetite decorated graphene oxide (MGO) magnetic composites was fabricated for the highly efficient immobilization of Eu(III) from aqueous solution. The as-synthesized MGO was characterized using different characterization techniques. The immobilization of Eu(III) onto MGO by an adsorption process was studied in the absence and presence of humic acid (HA) or fulvic acid (FA) using a batch technique. The results indicated that the adsorption of Eu(III) onto MGO is strongly dependent on pH but independent of ionic strength. The adsorption kinetics of Eu(III) onto MGO can be well described by the pseudo-second-order model and intra-particle diffusion model. A positive effect of HA or FA on Eu(III) adsorption onto MGO was found at low pH values, whereas a negative effect of HA or FA on Eu(III) adsorption onto MGO was observed at high pH values. Besides, the MGO magnetic composites showed good reusability for the removal of Eu(III) and could be utilized as an adsorbent in real wastewater treatment. The combination of the excellent adsorption capacity of GO and the magnetic properties of magnetite can be a promising candidate for the removal of Eu(III) and related radionuclides from aqueous solutions in nuclear waste management. (C) 2014 Elsevier B.V. All rights reserved.