Research on Processes for Leaching of Vanadium From Low-grade Stone Coal Vanadium Ore

The processes for leaching of vanadium from low-grade coal vanadium ore were investigated.Vitriol leaching process,oxidation roasting—sulphuric acid leaching process,oxidation roasting—alkali leaching process and calcified roasting—sodium carbonate leaching process were examined.The results showed that by the oxidation roasting—vitriol leaching process,preferable leaching index can be acquired.At the conditions of roasting temperature of 850 ℃,roasting time of 2 h,the quantity of sulphuric acid was 60% to ore mass,leaching time of 6 h,the leaching rate of vanadium pentoxide was of 62.5%.