Abstract:With aid of FactSage’s thermodynamic analysis software, the effect of addition of fluorine-containing leaching agent on sulfuric acid leaching of blank roasted residue of stone coal was investigated. The results show that addition of fluorine-containing leaching agent can not strengthen direct reaction between sulfuric acid and vanadium in roasted residue. Muscovite is easily dissolved in sulfuric acid solution with addition of fluorine-containing leaching agent due to reaction of aluminum and silicon in muscovite crystal structure with fluorine to form the complex. Hematite is hardly to dissolve in pure sulfuric acid solution, however, with addition of fluorine-containing leaching agent, it is much easier to dissolve and generate solid product of FeF3?3H2O, thus reduce Fe3 concentration in lixivium.