Abstract: In order to solve the problems caused by traditional process of vanadium extraction,such as high pollution,high acid consumption,low vanadium leaching rate,regarding the stone coal from Hunan province as the research target,the conditioning tests of vanadium extraction were investigated by sulphating roasting-ultrasonic extraction.The results showed that when the stone coal was firstly treated with 18% sulfuric acid (mass ratio with stone coal),liquid-to-solid ratio at 1.2∶1 mL/g at 240 ℃ for 2.5 h,and then the roasted ore is treated by ultrasonic leaching with 8% phosphoric acid (mass ratio with stone coal),liquid-to-solid ratio at 2∶1 mL/g,and ultrasonic power of 100 W at 80 ℃ for 60 min,the leaching rate of vanadium reached 88.21%.Compared with the process of sulphating roasting-mechanical stirring leaching and the process of calcified roasting-ultrasonic leaching,the process had a better performance.The main reason was that agitation,cavitation,thermal and chemical effects of ultrasonic wave contributed to change the aggregation state of vanadium and accelerate the leaching of vanadium,so that the vanadium leaching was more sufficient.

Key words: Vanadium-containing stone coal, Sulphating roasting, Ultrasonic Leaching, Vanadium leaching rate