中文摘要：

对KOH亚熔盐浸出铌钽铁矿过程中Fe的转化行为进行了热力学计算分析。结果表明，铌钽铁矿中的Fe在浸出过程中不会转化为Fe（0H）2或Fe（OH）3，而是转化为FeO和K2O·Fe2O3等铁的化合物；并通过扫描电镜（SEM）及X射线能谱（EDAX）对包裹在未反应的颗粒表面上的固相产物层的形成过程和组成进行了分析，证明固相产物层的主要组成为铁的化合物。

英文摘要：

The conversion behaviour of iron in the process of niobium-tantalum ore leached with KOH sub-molten salt was investigated by thermodynamic calculation and analysis. The results indicate that iron would not be converted into Fe（OH）2 or Fe（OH）3, but FeO, K2O· Fe2O3. The formation process of solid product layer on the surface of unreacted core and itscomposition were analysed by SEM and EDAX.Based on the analysis results, it is proved that, during the leaching process of niobium-tantalum ore by KOH submolten salt, a solid product layer is formed on the surface of the unreacted core and its main composition is iron compound.