Synthesis of Fe–Ni/graphene oxide composite and its highly efficient removal of uranium(VI) from aqueous solution

Abstract

In this research, the Fe–Ni/graphene oxide composite (Fe–Ni/GO) was synthesized by the hydrothermal way and investigated to remove uranium(VI) from aqueous solution under various environmental conditions. Loading Fe–Ni on GO could obviously enhance the stability of Fe–Ni/GO. X-ray diffractometer analysis confirmed that the crystallization of Fe0 and Ni0 was formed in Fe–Ni/GO. The sorption and reduction of U(VI) by Fe–Ni/GO nanoparticles were confirmed by using Fourier transform infrared and X-ray photoelectron spectroscopy (XPS) analysis. Batch experiments displayed the sorption of U(VI) obtained equilibrium within 25 min following the second order reaction kinetics. Based on XPS analysis before and after sorption, the Fe–Ni could simultaneously involve the sorption and reduction of U(VI), and played a dominating impact on U(VI) removal. The introduction of Ni metal could promote U(VI) reduction through catalytic hydrogenation and electron transfer. Thus, Fe–Ni/GO exhibited more efficiency towards U(VI) removal compared to Fe/GO and Fe–Ni, and Fe–Ni/GO displayed outstanding maximum U(VI) removal capacity (384.62 mg/g). The results demonstrated that Fe–Ni/GO was a promising and feasible material for U(VI) removal from wastewater.