The direct production of high-purity copper from copper scrap is a promising approach for its recycling and addressing the supply–demand gap of copper. To enable more efficient production of high-purity copper, the distribution equilibria of trace elements (e.g., Fe, Ni, Pb, Sn, Sb, and Zn) between copper alloy and different flux systems (CaO–SiO2–FeOx, CaO–SiO2–FeOx–Al2O3, CaO–SiO2–FeOx–Na2O, CaO–SiO2–Na2O–P2O5, CaO–SiO2–Na2O–B2O3) were investigated at 1200 ºC and \({\text{p}}_{{{\text{o}}_{{2}} }}\) of 10–7.0 to 10–4.5 atm. The slag-to-metal distribution coefficients followed the order Sb < Ni < Pb < Sn < Fe (Zn), indicating that antimony and nickel are the most challenging impurities to remove during fire refining. Based on the findings, a novel fluxing strategy was developed using the CaO–SiO2–FeOx–Al2O3 flux system at 1200 °C and high oxygen partial pressures up to \({\text{p}}_{{{\text{o}}_{{2}} }}\) = 10–4.5 atm. Under such conditions, recycled copper purities of 99.5 wt% can be achieved after single-step refining. This analysis indicates that high-grade copper comparable to Standard Grade Electrolytic Copper (Cu% ≥ 99.9 wt%) can be attained through fire-refining alone by adjusting flux dosage, applying multiple refining stages, and using selected copper scrap.
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