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

Herein, Fe 3 O 4 /g-C 3 N 4 composites with different proportions were prepared to remove U(VI) from wastewater through photocatalytic reduction. The morphology, composites, and magnetism of the Fe 3 O 4 /g-C 3 N 4 composites were measured. The characterization results showed that Fe 3 O 4 nanoparticles were well distributed on the surface of g-C 3 N 4 , 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 Fe 3 O 4 and g-C 3 N 4 was also determined. It was found that Fe 3 O 4 /g-C 3 N 4 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-C 3 N 4 and 2.4 times that of pure Fe 3 O 4 . In addition, after five reaction cycles, the composite showed high photoreduction activity and magnetic properties.