Preparation of Fe3O4/TiO2 magnetic photocatalyst for photocatalytic degradation of phenol

In this study, Fe3O4 magnetic nanoparticles were prepared from FeCl2/FeCl3 and NaOH solution by chemical co-precipitation method in an impinging stream-rotating packed bed. Then, Fe3O4/TiO2 photocatalyst was prepared for photocatalytic degradation of phenol by sol–gel method using butyl titanate and Fe3O4 magnetic nanoparticles. The surface morphology, structure and crystalline phase of Fe3O4/TiO2 were characterized by high resolution transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometer, dynamic light scattering and ultraviolet–visible spectroscopy. A 100 mg L−1 phenol aqueous solution was used as the pollutant. The effects of calcination temperature, the dosage of butyl titanate, the dosage of catalyst and solution pH value on the photocatalytic activity of Fe3O4/TiO2 were investigated. The results showed that Fe3O4/TiO2 photocatalyst could be easily recovered from the solution by permanent magnet. The photocatalytic activity reached a maximum under the following conditions: calcination temperature, 400 °C; butyl titanate dosage, 10 mL; catalyst dosage, 3 g L−1; and solution pH value, 2.