A novel recycling approach for efficient extraction of titanium from high-titanium-bearing blast furnace slag

Abstract

The recycling of high-titanium-bearing blast furnace slag (TiO₂ > 23 wt.%) is an urgent problem that has attracted global research attention. To achieve high-efficiency, low-consumption, clean, and high value-added recycling utilization, a new process is proposed herein, which entails reacting a CH₄-H₂-N₂ gas mixture with the titanium-bearing blast furnace slag to initially produce Ti(C, N, O) at a low temperature, whereafter the product is purified and chlorinated. The effects of Fe₂O₃, urea, and sawdust on the reduction and carbonitriding characteristics are also investigated. The results indicate that the Fe₂O₃ additive can promote the formation of Ti(C, N, O), while urea and sawdust are instrumental for enhancing gas diffusion in solid powders. The proposed novel recycling process was assessed and it evinced many advantages and great feasibility.

Keywords: CH(4)-N(2)-H(2) gas mixture; Carbonitride; High titanium-bearing blast furnace slag; Sawdust; Ti(C, N, O); Urea.