Efficient uranium(VI) adsorption platform based on graphene oxide-supported TixAl1-xOy bimetallic oxide

Abstract

A novel graphene oxide-supported TixAl1-xOy bimetallic oxide for uranium removal was successfully fabricated by using sol–gel method. The introduction of graphene oxide could not only improve the dispersion of TixAl1-xOy nanoparticles, but also increase the active sites of the complexes. In static adsorption experiments, the adsorption efficiency and capacity of GO@TixAl1-xOy reached 97.8 % and 614.6 mg g−1 at T = 298 K and pH = 4, which were much higher than those of other bimetallic oxides. After five adsorption–desorption cycles, the adsorption efficiency of GO@TixAl1-xOy for uranium remained above 90 %, indicating the excellent applicability and regeneration in practical application. The adsorption process was consistent with the pseudo-second-order and the Langmuir models, manifesting the uniform single-layer chemisorption process of GO@TixAl1-xOy for uranium. The structure and morphology of GO@TixAl1-xOy before and after adsorption were analyzed by FTIR, SEM and XPS. The results showed that the excellent adsorption performance of GO@TixAl1-xOy for uranium was attributed to the strong complexation, oxygen vacancy filling and reduction. In a word, the graphene oxide-supported TixAl1-xOy bimetallic oxide processed a great potential in the removal of uranium from wastewater, providing a new idea for the synthesis of highly efficient adsorbents.