活性炭强化氧化亚熔盐介质中钒渣分解机理

Decomposition mechanism of vanadium slag by sub-molten salt medium with active carbon catalytic oxidation

活性炭强化亚熔盐介质中钒渣分解效果显著,添加10%(质量分数)活性炭即可实现215℃下铬的溶出率由0提高至近85%。以活性炭强化氧化亚熔盐介质中钒渣分解作用机制为重点展开研究。结果表明:活性炭的强化氧化作用主要与其吸附性能及活性氧(ROS)催化氧化性能相关。通过对活性炭表面ROS含量的测定,发现超氧自由基(O_2^-)的存在和生成是活性炭催化氧化亚熔盐介质中矿物分解的主因,且O_2^-随NOH浓度的升高含量大幅增加。活性炭表面的超氧根一方面作为催化剂促进反应的发生,另一方面可附着于活性炭巨大的比表面上和发达的孔隙结构中,通过活性炭与钒渣在液相中的接触对矿物进行氧化分解。

Active carbon(AC) can intensify the chromium extraction of vanadium slag in sub-molten salt medium remarkably.The reinforcement mechanism of vanadium slag decomposition by addition of active carbon in sub-molten salt medium was investigated.The results show that the reinforcement effect of AC is related with its adsorption performance and reactive oxygen species(ROS) catalytic oxidation performance.By measuring the ROS content on AC surface,the catalytical oxidation role of ultra-oxygen(O_2^-) on the decomposition of vanadium slag in sub-molten salt medium is confirmed.O_2^- can be detected on the surface of active carbon,and O_2^- concentration increased greatly with the increase of Na OH concentration.O_2^- can be adsorbed on the huge surface and multi pores of AC,and effect catalytic oxidation role on the chromium extraction by contacting with vanadium slag in liquid phase.