Abstract: In order to find a process which could increase the leaching velocity of vanadium，roasting-pressure acid leaching of vanadium on stone coal from Tongshan in Hubei was investigated.Results showed that，the optimal operation conditions are as followed:the roasting temperature was 850 ℃，the roasting time was 60 min，the kettle pressure was 1.0 MPa，initial concentration of sulfuric acid was 15%，ratio of liquid to solid was 1.5 mL/g，leaching temperature was 150 ℃ and leaching time was 120 min，with these conditions the vanadium leaching rate could reach 80.51%.The changes of mica mineral structure during leaching process were analyzed by Infrared Spectrometry analysis and the effect of temperature on vanadium efficiency was studied from the aspect of leaching kinetics.The results indicated that pressure acid leaching could destruct the crystal lattice of mica that was helpful for the release of vanadium and the increase of vanadium leaching efficiency.The leaching kinetics analysis results indicated that:effect of leaching temperature on vanadium efficiency was conspicuous，when the leaching temperature ranged from 60 to 120 ℃，the apparent activation energy was 41.603 kJ/mol and the leaching was controlled by surface chemical reaction.When the temperature ranged from 150 to 210 ℃，the apparent activation energy was 4.319 kJ/mol and the leaching was controlled by inner diffusion of reactants.As pressure acid leaching could raise the leaching temperature over 100 ℃，the destruction velocity of mica crystal lattice could be raised effectively and the vanadium leaching time could be shorten effectively.

Key words: Pressure acid leaching, Stone coal, Vanadium extraction, Kinetics