Implications of Direct Use of Slag from Ironmaking Processes as Molten Oxide Electrolyte

Abstract

Abstract The thermochemical and electrical behavior of ironmaking slag produced from titanomagnetite concentrates has been assessed in the vicinity of its tapping temperature. A combination of electrochemical measurements in a modified thermal imaging furnace and computational thermodynamic calculations was employed to elucidate its potential use as a molten oxide electrolyte for the extraction of high-purity metal. The results show that the presence of entrained iron species in the ironmaking slag decreases the faradaic efficiency of the electrolysis. Thermodynamic predictions reveal a small electrochemical window of operation between the decomposition of silica and titania, which might result in the co-reduction of titanium and silicon ions from the melt. Practical considerations for the electrochemical production of metal directly from the ironmaking process are discussed, and further experimental investigation of the electrochemical behavior of this material is justified.