Abstract: Activated carbon-nickel ferrite (AC-NiFe₂O₄) has been successfully synthesized using activated carbon, NiSO₄·6H₂O, and FeCl₃·6H₂O as the raw materials by the hydrothermal method at 180 ^oC for 10 h. The as-synthesized sample was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and vibrating sample magnetometer. The photo-Fenton degradations of model pollutants methylene blue, rhodamine B, and malachite green were conducted in the presence of oxalic acid using AC-NiFe₂O₄ as photo-Fenton catalyst under λ > 400 nm visible light. The results showed that the AC-NiFe₂O₄ catalyst can effectively decompose the organic pollutants under visible light irradiation and the degradation ratio of organic pollutants in the concentration of 20.0 mg/L reached over 90% in 10 h, whereas the NiFe₂O₄ catalyst appeared no photocatalytic activity under the similar conditions. The catalytic activity did not exhibit significant loss after 8 runs, showing the potential application of AC-NiFe₂O₄ as an effective photo-Fenton catalyst to degrade organic pollutions.

Key words: activated carbon, nickel ferrite, heterogeneous Fenton catalyst, visible light, catalytic degradation