Abstract: In view of the problems of high cost,high pollution and low efficiency of the existing vanadium extraction process from vanadium-containing steel slag,this study carried out an experimental study on vanadium extraction from the vanadium-containing steel slag with V2O5 content of 0. 94 % in Panzhihua,Sichuan. The research showed that the main phases of vanadium-bearing steel slag were SiO2 ,Ca2 SiO4 ,MgFe2O4 ,Ca2Fe1. 2Mg0. 4 Si 0. 4O5 ,FeO,Ca3. 18Fe15. 48Al 1. 34O28 and Ca2Fe2O5 . The new phases of Fe3O4 and Ca12Al 14O33 were formed after the blank roasting treatment,and the diffraction peak intensity of Ca2 SiO4 and Ca2Fe1. 2Mg0. 4 Si 0. 4O5 was enhanced,which confirmed that the high temperature roasting made some elements oxidized from low valence to high valence. The main phase of the the sulfuric acid leaching residue from the steel slag calcined at 900 ℃ was CaSO·4 2H2O,with a small amount of SiO2 ,MgFe2O4 and Fe3O4 ,indicating that sulfuric acid effectively dissolves some minerals and creates conditions for the dissolution of vanadium. Under the conditions of blank roasting temperature of 900 ℃ ,sulfuric acid concentration of 14%,leaching liquid-solid ratio of 8 ∶ 1 mL/ g,leaching temperature of 40 ℃ and leaching time of 25 min,the leaching rate of vanadium could reach 90. 18%. Compared with the traditional process,this process has the advantages of no additive,low leaching temperature and short time,with reduced waste gas emissions by 60%,lower energy consumption by 40%,and decreased acid consumption by 35%,which provides a clean and efficient solution for the resource utilization of vanadium-containing steel slag. 

Key words: steel slag containing vanadium,blank roasting,sulfuric acid leaching,vanadium leaching rate