Nickel ferrite-ferrous oxide magnetic ceramic powder synthesized for Fenton-like treatment of industrial organic pollutants: a characterization study

Abstract

Dye-contaminated industrial wastewater causes pollution and environmental concerns. The Fenton process is a simple wastewater treatment technology that can be applied at room temperature, atmospheric pressure, and near neutral pH. The heterogeneous Fenton-like process involves ferrous or ferric catalysts immobilized on solid supports to reduce the formation of sludge, which is a secondary pollutant. In this work, a nickel ferrite-ferrous oxide magnetic ceramic powder catalyst was prepared using solid-state combustion synthesis. An extract of Carica papaya L. leaf was used as a green reducing and capping agent to generate α-Fe₂O₃ hematite particles. The as-prepared catalyst contained a major phase of NiFe₂O_4, and minor phases of FeO and FeNi₃. Under UV and LED irradiation, the catalyst could degrade more than 90% of methylene blue dye via the Fenton-like process. The high degradation efficiency of the process was due to the synergistic effects derived from the promotion of iron ion conversion and •OH radical generation. The nickel ferrite-ferrous oxide magnetic ceramic powder was highly stable, reusable and achieved excellent recoveries.