▎ 摘　　要

A metal oxide decorated graphene oxide composite (GO-MO) is prepared via fixation of manganese dioxide (MnO2) on the surface of graphene oxide (GO). The composite is used as a sorbent for the separation of europium and cerium ions from aqueous solutions. The synthesized materials are characterized using scanning electron microscopy, thermogravimetric analysis, X-ray diffraction, Raman spectroscopy, and Fourier transform infrared spectroscopy. The role of different variables on the sorptive ability of these materials is studied. Two simplified kinetic models, pseudo-first order and pseudo-second order, are applied to describe the kinetics of the sorption process. It is found that sorption of Eu(III) and Ce(III) ions on the synthesized sorbents could be described more favorably by the pseudo-second-order kinetic model. Sorption data are analyzed with Freundlich and Langmuir isotherm models. Desorption of europium and cerium ions from loaded sorbents is carried out using different eluents. Eu(III) ions are easily desorbed from loaded samples using 0.01 m EDTA while Ce(III) ions are easily eluted using 0.01 m AlCl3. The obtained data clarify that the synthesized composite could be considered as a promising candidate for preconcentration and separation of some lanthanide elements from aqueous solutions.