高铁闪锌矿还原浸出液直接萃取法分离回收铟

针对高铁闪锌矿湿法炼锌过程中产出的还原浸出液提出了预还原Fe3+,P204直接萃取回收铟的工艺。还原浸出液中铁达到50g/L以上,Fe3+占到10%左右,经预还原后Fe3+降低到0.5g/L左右,还原过后的浸出液进行直接萃取分离回收铟。考察了原液pH、相比、有机相浓度、搅拌转速等条件对整个萃取过程的影响。铟的萃取率主要受P204浓度和溶液pH的影响,萃取过程平衡时间为1~2min。三级逆流萃取综合验证试验表明,铟的萃取过程稳定,萃取率在98%以上,铟铁分离效果良好,分离系数达到10000以上,整个过程无乳化现象产生。直接萃取法回收铟具有操作简单、流程短、直收率高等特点。

Directly Extract and Separat Indium from High Iron Sphalerite

The technology of prereduction Fe₃ -P204 extraction recovery of indium directly have been proposed to dispose the high iron sphalerite reduction lixivium in zinc hydrometallurgy process. The concentration of Fe reached more than 50g/L and the concentration of Fe₃ account for about 10% in the reduction leaching. The concentration of Fe₃ reached to about 0.5g/L after prereduction and the reduction lixivium is used to direct extraction. The influence of pH, phase ratio, organic phase concentration, stirring speed and other conditions for the extraction process have been investigated. Indium extraction rate is mainly influenced by P204 concentration and solution pH and extraction balance time is 1 to 2 minutes. Three-stage countercurrent extraction comprehensive validation experiments show that the indium extraction process stability, extraction rate is over 98% and indium iron separating effect is good and the separation factor is above 10000 and no emulsification phenomenon occurs throughout the process. Direct extraction method has simple operation, short process, high recovery efficiency advantages.