New calcification roasting–sulfuric acid leaching：A zero-discharge, cleaner-sustainable and multi-value-added products route of vanadium

In the current vanadium-only process, huge-high valuable metal-rich solid-liquid waste discharge has caused serious environmental problems. Discovery based on the principle of element separation, feasibility analysis and method evaluation, a new method was established to recover Fe, V, Mn and Mg via a zero-discharge and cleaner-sustainable multi-product route of calcification roasting-sulfuric acid leaching and precipitating, flotation, electrolysis, extraction-stripping and evaporative crystallization. This process includes one main-line and two sub-lines, generating a variety of products: Mn and V2O5, MnSO4, (NH4)2Mg(SO4)2. Meanwhile, 40.8% Fe content of Fe-rich material are obtained. Key findings of this work may provide a promising route for the efficient utilization of vanadium slag resources and sustainable development of great scientific value-added to industrial promotion and application and narrow the industry knowledge gap.