Photo-fenton degradation of RhB via transition metal oxides composite catalyst Fe3O4/CuO under visible light optimized using response surface methodology

Abstract

ABSTRACT This paper reports on the facile synthesis and degradation of a heterogeneous photo-Fenton catalyst Fe3O4/CuO to improve the conventional photo-Fenton catalyst. The results using Fe3O4/CuO as a heterogeneous photo-Fenton catalyst showed that the degradation of 98.9% was achieved through visible light irradiation of 10 mg·L−1 RhB solution at pH 2 in the presence of 30 mmol·L−1 H2O2 for 1 h. In addition, the process parameters were optimised using the Response Surface Methodology (RSM). After optimisation, optimum conditions of process factors such as catalyst dosage, initial concentration of H2O2, pH and initial concentration of RhB were determined as 17 mg·L−1, 28.14 mmol·L−1,2.32 and 5.31 mg·L−1, respectively. The quenching experiments of active species demonstrated that hydroxyl radical (·OH) was the main active group. Cycling experiments proved that the catalyst has good reusability. Finally, the possible reaction pathways of the photo-Fenton catalyst under the conditions of visible light and hydrogen peroxide were proposed.