钒渣亚熔盐工艺中主要物相演变及钒、铬元素微区转浸率研究

Main Phase Evolutions and Micro Zone Leaching Rate of Vanadium and Chromium in Sub-molten Salt Process for Vanadium Slag

基于亚熔盐反应可以在低温下高效高选择性将钒渣中的钒、铬元素转化为可溶性盐,对钒铬渣亚熔盐反应前后主要物相演变过程,钒、铬元素的赋存变化规律以及钒铬物相微区转化率进行分析研究。结果表明,表面晶格多缺陷比致密的钒铬尖晶石更有利于O2-离子的晶格取代,加速钒铬尖晶石的分解过程;亚熔盐反应前后Cr元素的回收率为99.63%,而V元素的回收率为90.01%;主要含V物相微区转化率计算证明,亚熔盐反应后Fe2O3中V含量的增加是导致其回收率低的主要原因。

Based on the sub-molten salt process that vanadium and chromium in vanadium slag can be efficiently and selectivity converted into soluble salts at low temperatures,the main phase evolutions,occurrence and change laws of vanadium and chromium elements,and micro zone conversion rate of vanadium and chromium for vanadium-chromium slag before and after the sub molten salt reactions were studied.The results show that the vanadium-chromium spinel with lattice defects on the surface is more favorable for the lattice substitution of O2- than the dense vanadium-chromium spinel,and the decomposition of vanadium-chromium spinel with the defects is accelerated.The recovery rate of Cr element before and after the sub-molten salt reactions is 99.63%,while the recovery rate of V element is 90.01%.The micro zone conversion rate of the main vanadium phases proves that the increase of vanadium content in Fe2O3 after the reactions of sub-molten salt is the main reason for the decrease of V recovery rate.