Experimental and theoretical studies of spherical β-cyclodextrin modified titanium dioxide composites for uranium removal

Abstract

With the fast development of the nuclear industry, it is inevitable that a considerable amount of uranium (U) is discharged into the environment during mining, use, and disposal processes, which can result in serious radioactive contamination. In this study, the spherical β-cyclodextrin modified titanium dioxide (β-CD/TiO2) was prepared by a simple hydrothermal method for the capture of U(VI). The removal of U(VI) on β-CD/TiO2 was dependent on solution pH. The maximum adsorption capacity of β-CD/TiO2 at pH 5.0 reached 129.8 mg/g for U(VI). The thermodynamic study confirmed that the capture of U(VI) was a spontaneous process. According to the XPS analysis, the hydroxyl groups of β-CD/TiO2 were responsible for U(VI) removal, which was further demonstrated by DFT calculation at the molecular level. The findings presented in this study are important to the removal of radionuclides from wastewater.