Carbothermic reduction of vanadium titanomagnetite with the assistance of sodium carbonate

Abstract

The carbothermic reduction of vanadium titanomagnetite concentrate (VTC) with the assistance of Na₂CO₃ was conducted in an argon atmosphere between 1073 and 1473 K. X-ray diffraction and scanning electron microscopy were used to investigate the phase transformations during the reaction. By investigating the reaction between VTC and Na₂CO₃, it was concluded that molten Na₂CO₃ broke the structure of titanomagnetite by combining with the acidic oxides (Fe₂O₃, TiO₂, Al₂O₃, and SiO₂) to form a Na-rich melt and release FeO and MgO. Therefore, Na₂CO₃ accelerated the reduction rate. In addition, adding Na₂CO₃ also benefited the agglomeration of iron particles and the slag—metal separation by decreasing the viscosity of the slag. Thus, Na₂CO₃ assisted carbothermic reduction is a promising method for treating VTC at low temperatures.

Keywords

vanadium titanomagnetite / sodium carbonate / phase transformation / carbothermic reduction / slag—metal separation

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