A novel method for vanadium slag comprehensive utilization to synthesize Zn-Mn ferrite and Fe-V-Cr alloy

Vanadium slag is a by-product from steelmaking process of vanadium-titanium magnetite, which mainly contains FeO, MnO, V2O3, and Cr2O3, The elements Fe and Mn are major components of Mn-Zn ferrite. The elements V and Cr are major components of V-Cr alloy. In view of the potential application in these study, a Mn0.8Zn0.2Fe2O4 of high saturation magnetization (Ms = 68.6 emu/g) and low coercivity (Hc = 3.3 Oe) was successfully synthesized from the leaching solutions of vanadium slag by adding appropriate chemical reagents, ZnCl2 and MnCl2·4H2O, via roasting at 1300 °C for 1 h. The minor components (CaO and SiO2) in the leaching solution of vanadium slag segregated to the grain boundaries resulting in increasing the resistivity of ferrite. The value of DC resistivity of Mn0.8Zn0.2Fe2O4 at 25 °C reached 1230.7Ω m. The residue containing Fe, V and Cr was chlorinated by AlCl3 and the Fe3+, V3+, and Cr3+ ions were released into the NaCl-KCl eutectic. The current-time curve for the electrolysis of molten salt was investigated. Alloy (Fe, V, and Cr) of granular shape was obtained. The residue can be used to produce the mulite. This process provided a new approach to utilize slag from steelmaking.