Metal-doped (Cu,Zn)Fe₂O₄ from integral utilization of toxic Zn-containing electric arc furnace dust: An environment-friendly heterogeneous Fenton-like catalyst

Pure metal-doped (Cu,Zn)Fe₂O₄ was synthesized from Zn-containing electric arc furnace dust (EAFD) by solid-state reaction using copper salt as additive. The effects of pretreated EAFD-to-Cu₂(OH)₂CO₃∙6H₂O mass ratio, calcination time, and calcination temperature on the structure and catalytic ability were systematically studied. Under the optimum conditions, the decolorization efficiency and total organic carbon (TOC) removal efficiency of the as-prepared ferrite for treating a Rhodamine B solution were approximately 90.0% and 45.0%, respectively, and the decolorization efficiency remained 83.0% after five recycles, suggesting that the as-prepared (Cu,Zn)Fe₂O₄ was an efficient heterogeneous Fenton-like catalyst with high stability. The high catalytic activity mainly depended on the synergistic effect of iron and copper ions occupying octahedral positions. More importantly, the toxicity characteristic leaching procedure (TCLP) analysis illustrated that the toxic Zn-containing EAFD was transformed into harmless (Cu,Zn)Fe₂O₄ and that the concentrations of toxic ions in the degraded solution were all lower than the national emission standard (GB/31574—2015), further confirming that the as obtained sample is an environment-friendly heterogeneous Fenton-like catalyst.