关键词: 酸浸, 电场强化, 焙烧, 氧化还原

Abstract: In order to explore the electric field reinforcement on the vanadium leaching extraction from stone coal， the condition tests were conducted regarding vanadium-contained stone coal in Shaanxi province as the research object， sulfuric acid as acid infusions. The electric field intensity on the leaching effection were investigated for the samples before and after roasting， and strengthening mechanism were analyzed through the open circuit potential and cycle volt-ampere curve test for the leaching liquid. Under the conditions of sulfuric acid concentration of 20%， leaching temperature of 90 ℃， leaching time of 4 h and liquid-solid ratio of 7∶1， the leaching rate of vanadium from raw stone coal was 62.50%， and the leaching rate increased to 67.32% when the electric field was applied at 1 000 mA. For the roasted samples roasted at 600 ℃ for 3 h， the leaching rate of vanadium was 68.96% without the application of electric field， and increased to 71.31% when the electric field was applied at 1 000 mA. After the electric field is applied， the leaching solution changes from light green to blue， and the vanadium is oxidized to a higher valence state. The results of mechanism study showed that there were vanadium ions with different valence states of VO2+ and VO2+ in the leach solution， and VO2+ was reduced in the leaching system under the action of electric field， and two pairs of REDOX characteristic peaks appeared.

Key words: acid leaching, electric field intensity, roasting, redox