Thermodynamic prediction of melting of copper-electrolyte slime

Abstract

Balance calculations of multicomponent equilibrium compositions in the gas–liquid–solid system under oxidizing smelting of the copper-free copper-electrolyte slime, during which sulfur, selenium, and tellurium dioxides transfer into the gas phase, while compounds of lead, copper, antimony, iron, and aluminum are concentrated in the composition of the silicate slag, are performed with the help of the Outotec’s Chemical Reaction and Equilibrium Software HSC Chemistry program. It is established that, under optimal conditions of oxidizing smelting of the charge (100 kg) of the electrolyte slime (O₂ ≈ 0.9 kg, SiO₂ ≥ 6%, CaO ~ 3%, t = 1200°C), lead, antimony, and arsenic almost completely transfer into the silicate slag, while copper and silver (above 91%) transfer into the matte. Selenium is distributed between the gas phase (49.8%), matte (24.1%), and metallic phase (26.1%), while tellurium is distributed between sublimates (14.4%), silicate slag (8.4%), and matte (77.2%).