Synthesis of (Ni,Mg,Cu)Fe2O4 from nickel sulfide ore: A novel heterogeneous photo-Fenton-like catalyst with enhanced activity in the presence of oxalic acid

Metal doped nickel ferrite was successfully synthesized from nickel sulfide ore by an acid leaching-coprecipitation-calcination method. The as-prepared Ni0.63Mg0.30Cu0.02Fe2O4 exhibited enhanced Fenton-like catalytic property in degrading Rhodamine B (RhB) assisted by oxalic acid (H2C2O4) under visible-light (Vis) irradiation. The factors including solution pH value, catalyst amount and H2C2O4 concentration affecting the degradation efficiency of RhB were systematically examined and the related degrading mechanism was also discussed. The obtained Ni0.63Mg0.30Cu0.07Fe2O4 showed degradation efficiency up to 97.2% and total organic carbon (TOC) removal efficiency about 85.6% in 90 min under the optimum conditions. More importantly, the good catalytic activity and reuse exploitability of the Ni0.63Mg0.30Cu0.07Fe2O4 catalyst with low-cost synthesis from nickel sulfide ore make it have advantageous in treating industrial wastewater containing organic contaminants.