Separation and Purification Technology, Vol.174, 425-431, 2017
Spectrostopic and modeling investigation of efficient removal of U(VI) on a novel magnesium silicate/diatomite
A novel magnesium silicate/diatomite sorbent (MSD) was fabricated using a facile hydrothermal method. The interaction mechanism of U(VI) on MSD was investigated by batch, spectroscopic and modeling techniques. The maximum adsorption capacity of MSD for U(VI) (31.54 mg/g) is significantly higher than that of diatomite (12.74 mg/g). XPS analysis indicated that the oxygen-containing groups (e.g., Si-OH) of MSD were responsible for the high efficient removal of U(VI) from aqueous solutions. The fitted results of surface complexation modeling showed that the adsorption of U(VI) on MSD at pH <4.0 and pH > 4.5 was attributed to cation exchange and inner-sphere surface complexation, respectively. These findings suggested that MSD could be a favorable sorbent for the efficient removal of U(VI) in the environmental cleanup. (C) 2016 Elsevier B.V. All rights reserved.