Innovative process of manganese recovery from steelmaking slag by sulfurization

Manganese is a key alloying element in various advanced steel productions for improving mechanical properties such as strength and formability. The production of advanced steel has led to an increase in Mn consumption, especially in high-purity grade of Fe-Mn alloys. Despite the important role of Mn in steel products, a recycling strategy to stabilize Mn resources has not yet been investigated. In Japan, the amount of Mn consumed as an alloying element in the steelmaking process is similar to the amount of Mn emitted as a steelmaking slag. However, the separation of P from steelmaking slag is necessary to obtain valuable resources of Mn because the steelmaking slag generally contains about 1.7 mass% P in the form of P2O5. The authors have proposed an innovative process for recycling Mn from steelmaking slag via sulfurization of slag because the phosphorus sulfide is unstable at high temperature