The effect of magnesium oxide morphology on adsorption of U(VI) from aqueous solution

Magnesium oxide particles with different morphologies have been synthesized by using different precursors of magnesium, and urea as precipitating agent. The as-prepared samples, and the magnesium oxide materials before and after adsorption of U(VI), which were characterized by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX), TG and DSC thermal analysis and so on. The adsorption properties of Mg600-N, Mg600-S and Mg600-CI adsorbents to U(VI) were estimated and compared. The treatment of uranium-containing wastewater with magnesium oxide was studied under static state in the laboratory, and also the effects of adsorption time, pH value of wastewater and temperature were discussed. Through the investigation of adsorption thermodynamics and adsorption kinetics, the adsorption capacity of the three types of MgO particles for uranium more than 1600 mg g(-1), the optimum pH was 3.0-4.0, and the thermodynamic parameter calculation results indicate that the adsorption process is a spontaneous endothermic process. (C) 2017 Elsevier B.V. All rights reserved.