Research progress on the extraction and separation technology of V and Ti in vanadium-titanium slag: A review

Vanadium-titanium slag is a critical secondary resource for global vanadium-titanium production. However, the efficient separation of V and Ti from such complex substances remains a major challenge. This review evaluates how different ironmaking routes dictate slag composition and further influence the recovery behavior of vanadium and titanium. Blast furnace slag generally facilitates vanadium enrichment, but titanium utilization is restricted because Ti mainly exists in stable perovskite phases. In contrast, direct reduction-electric furnace routes yield Ti-rich slag more suitable for titanium recovery. Recovery strategies currently available are critically evaluated in terms of extraction efficiency, environmental sustainability, and industrial feasibility. Among them, sodium roasting remains the most mature vanadium recovery route, with vanadium leaching efficiencies typically exceeding 90%, while calcium-magnesium composite roasting exhibits superior environmental compatibility and risk balance. For titanium recovery, metallothermic reduction provides the highest economic value, whereas conventional acid leaching routes suffer from high reagent consumption and waste generation. Furthermore, industrial feasibility is comparatively discussed from a techno-economic perspective. Based on the comprehensive evaluation of extraction performance and industrial feasibility, the most promising recovery routes are identified, providing useful guidance for the development of more efficient and sustainable V-Ti recovery processes.