Element partitioning during the co-smelting of complex antimony-gold concentrate and lead concentrates

Focusing on the challenges associated with the comprehensive recovery of valuable metals from complex antimony-gold concentrates, such as high energy consumption and metal dispersion in conventional processes, this study proposes a co-smelting method involving oxygen-enriched blowing of such concentrates together with lead concentrate. By leveraging the effective collection of gold by lead and antimony, the process enables efficient recovery of Sb, Pb, and Au, while optimized sulfur utilization contributes to reduced energy consumption. Using FactSage thermodynamic software, viscosity analysis was conducted on the FeO-SiO 2 -CaO-ZnO-Fe 3 O 4 -PbO multicomponent slag system. The effects of smelting temperature, oxygen concentration, Fe/SiO 2 (mass fraction), and CaO/SiO 2 (mass fraction) on the distribution of Pb, Sb, and Au among the slag, matte, and alloy phases were systematically investigated. The results show that under the optimal conditions (1250 ℃, 50 % oxygen concentration, Fe/SiO 2 1.1, CaO/SiO 2 0.5), a Pb-Sb alloy grade of 90.83 % was achieved, with direct recovery rates of 55.85 % for Pb and 51.68 % for Sb, while Au loss in the slag was only 8.35 %, indicating effective reduction of gold loss. This study provides both a theoretical foundation and a process reference for the green and efficient smelting of complex antimony-gold resources.