(1. 中国科学院 过程工程研究所，北京 100190；
2. 中国科学院大学，北京 100049；
3. 中国恩菲工程技术有限公司，北京 100038)
摘 要: 对钒渣在KOH亚熔盐体系中的分解动力学进行研究，考察反应温度、碱矿质量比、粒度、气流量等工艺参数对钒渣分解过程的影响，获得最优工艺参数，并对反应机理进行探讨。结果表明，反应温度是最重要的影响因素；钒渣最优浸出条件如下：在反应温度为180 ℃，碱矿比4:1，KOH碱浓度75%，搅拌速率700 r/min，反应时间300 min，常压通氧气流量为1 L/min的反应条件下，最终钒、铬的浸出率分别达到95%和90%以上。钒渣在KOH亚熔盐介质中氧化分解遵循缩核模型，并主要受内扩散控制，钒和铬分解的表观活化能分别为40.54和50.27 kJ/mol，钒铬尖晶石的氧化以铁橄榄石、石英相的氧化分解为前提。
关键字: 钒渣；氢氧化钾；亚熔盐；内扩散
（1. Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
2. University of Chinese Academy of Sciences, Beijing 100049, China;
3. China Enfi Engineering Corpor）
Abstract:The dissolution behavior of vanadium slag was studied by decomposing the slag in KOH sub-molten salt. The effects of reaction temperature, KOH-to-ore mass ratio, particle size and gas flow were examined for obtaining the optimum process parameters. And the dissolution process mechanism was also investigated. The results show that reaction temperature is the most significant factor on vanadium and chromium extraction efficiency. Under the conditions of temperature of 180 ℃, initial KOH-to-ore mass ratio of 4:1, KOH solution content of 75% (mass fraction), stirring speed of 700 r/min, and gas flow of 1 L/min, vanadium and chromium extraction rates obtained are greater than 95% and 90% after 300 min, respectively. The results show that decomposing process of vanadium slag in KOH sub-molten salt is well interpreted with the shrinking core model under internal diffusions control. The apparent activation energies of vanadium and chromium are 40.54 and 50.27 kJ/mol, respectively. Vanadium and chromium spinels are oxidized after the decomposition of fayalite and quartz phases.
Key words: vanadium slag; potassium hydroxide; sub-molten salt; internal diffusions
