α-Fe2O3/Cu2O(SO4) composite as a novel and efficient heterogeneous catalyst for photo-Fenton removal of Orange II

Abstract

Hematite (α-Fe2O3), as one of Fenton reagents, is widely investigated for the treatment of wastewater in the field of advanced oxidation processes (AOPs). Considering the fast charge carrier recombination of hematite (α-Fe2O3), we have successfully synthesized a novel and high active heterogeneous Fenton catalyst α-Fe2O3/Cu2O(SO4) for the degradation of organic pollutants. The results show that the as-obtained Cu2O(SO4)-Fe9 composite exhibits excellent degradation properties of Orange II. 98.9% degradation rate was achieved for 100 mL of 50 mg/L Orange II solution in the condition of 0.3 g/L Cu2O(SO4)-Fe9 catalyst, 3 mM H2O2 and pH = 3.5. The degradation rate constants of Cu2O(SO4)-Fe9 in the photo-Fenton-like system are 9.33 and 4.07 times of Cu2O(SO4) and α-Fe2O3, respectively. In addition, the mechanism and pathway for the degradation of Orange II were proposed. The scheme of combining copper-based oxysulfate Cu2O(SO4) with hematite (α-Fe2O3) could improve the efficiency of charge carrier separation, which will further enhance the catalytic activity and expand its application in water purification.