Microwave hydrothermal synthesis, characterization and excellent uranium adsorption properties of CoFe2O4@rGO nanocomposite

To improve the adsorption performance and simplify uranium separation from aqueous media in post-treatment processes, a magnetic CoFe2O4@rGO composite was synthesized by microwave-hydrothermal method. The results of XRD, Raman, TEM/HRTEM, FTIR, BET and VSM characterization show that spinel-type cobalt ferrite CoFe2O4 nanoparticles ca. 13.4 nm in size are dispersedly anchored on the graphene sheet, and the saturation magnetization of the nanocomposite is 46.7 mA/(m(2)center dot g). The effects of different pH, initial concentration and other conditions on uranium adsorption capacity were investigated, and adsorption kinetics equations were fitted to determine the adsorption behaviour of uranium on CoFe2O4@rGO in simulated uranium-containing seawater. It was observed that the uranium adsorption capacity of CoFe2O4@rGO composite at pH=5 is 127.6 mg/g, which is 1.31 and 2.43 times that of rGO and pure CoFe2O4. The adsorption process conforms to Langmuir and quasi-second-order kinetic model. The excellent adsorption performance of CoFe2O4@rGO makes it potentially useful in the treatment of uranium-polluted water.

Automated summary

The magnetic CoFe2O4@rGO composite synthesized by microwave-hydrothermal method shows excellent uranium adsorption performance, making it potentially useful in the treatment of uranium-polluted water.