Removal of U(VI) from aqueous solution via photoreduction over Fe3O4/g-C3N4 composite under visible light irradiation

Abstract Herein, Fe3O4/g-C3N4 composites with different proportions were prepared to remove U(VI) from wastewater through photocatalytic reduction. The morphology, composites, and magnetism of the Fe3O4/g-C3N4 composites were measured. The characterization results showed that Fe3O4 nanoparticles were well distributed on the surface of g-C3N4, resulting in the good magnetism and corresponding excellent separation ability of the composites. The U(VI) removal efficiency of the composites with different ratios of Fe3O4 and g-C3N4 was also determined. It was found that Fe3O4/g-C3N4 with an Fe content of 14% showed the highest U(VI) removal efficiency of 98.7% after 25 min. The photocatalytic reaction rate constant was 0.161 min−1, which was 2.9 times that of pure g-C3N4 and 2.4 times that of pure Fe3O4. In addition, after five reaction cycles, the composite showed high photoreduction activity and magnetic properties.