Formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate by adding CaCO₃

Abstract

The formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate (VTC) by adding CaCO₃ was investigated. Thermodynamic analysis was employed to show the feasibility of calcium titanate formation by the reaction of ilmenite and CaCO₃ in a reductive atmosphere, where ilmenite is more easily reduced by CO or carbon in the presence of CaCO₃. The effects of CaCO₃ dosage and reduction temperature on the phase transformation and metallization degree were also investigated in an actual roasting test. Appropriate increase of CaCO₃ dosages and reduction temperatures were found to be conducive to the formation of calcium titanate, and the optimum conditions were a CaCO₃ dosage of 18wt% and a reduction temperature of 1400°C. Additionally, scanning electron microscopy-energy dispersive spectrometry (SEM-EDS) analysis shows that calcium titanate produced via the carbothermic reduction of VTC by CaCO₃ addition was of higher purity with particle size approximately 50 µm. Hence, the separation of calcium titanate and metallic iron will be the focus in the future study.

Keywords

vanadium titanomagnetite concentrate / calcium carbonate / carbothermic reduction / metallic iron / calcium titanate

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