Abstract

The removal mechanism of U(VI) on Mg–Al-layered double hydroxide-supported graphene oxide (LDH/GO) composites was investigated by batch, spectroscopic, and surface complexation modeling. The batch experiments showed that the enhanced removal of U(VI) on LDH and LDH/GO composites in the presence of carbonate was observed at pH < 5.0, whereas the presence of carbonate significantly inhibited U(VI) removal at pH starting from 7.0 to 9.0. It is demonstrated that the oxygenated functional groups (i.e., −OH) were responsible for the high effective removal of U(VI) by XPS analysis. The results of XANES and EXAFS spectra indicated that adsorption of U(VI) on LDH/GO composites was inner-sphere surface complexation. According to surface complexation modeling, the removal of U(VI) on LDH/GO composites can be satisfactorily fitted by a diffuse layer model with an ion exchange (X2UO2) and two inner-sphere surface complexes (SOUO2+ and SOUO2(CO3)23– species). The maximum adsorption capacities of LDH and LDH/GO composit...

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.