铟反萃液除锡工艺研究与应用

在采用湿法炼锌还原浸出后液进行铟的回收过程中,部分锡进入反萃液中,影响后续精铟质量,除锡渣中含有铟、锡等杂质,锡会在系统中逐步富集,影响萃取剂的使用寿命,降低生产效率.本文进行了采用预调pH值-H2 O2氧化方法去除反萃后液中锡的研究,分别对终点pH值、双氧水加入量、反应时间等条件进行试验,考查不同条件下的除锡效果,并...

Research and Application of Tin Removal from Indium Stripping Solution

In the process of recovering indium from the post-reduction leaching solution during hydrometallurgical refining of zinc,part of tin enters the stripping solution,which affects the quality of subsequent refined indium.Due to the impurities such as indium and tin in the tin removal residue,tin will be gradually enriched in the system,as to affect the service life of extractant and reduce the production efficiency.In this paper,the removal of tin in the solution after stripping was studied by using the pre-adjustment of pH value-H₂O₂ oxidation method.Condition tests were made on endpoint pH value,amount of hydrogen peroxide added,reaction duration,etc.to investigate the tin removal effects under different conditions,and exploration was made on tin removal from tin removal residue by means of acid leaching and alkali leaching.The results show that the separation of indium and tin can be achieved by controlling the temperature of indium stripping solution at 50℃,endpoint pH at about 2.0,reaction time at 1 h,amount of hydrogen peroxide added at 5 g/L and the hydrogen peroxide being added in a low speed.Using concentrated sulfuric acid or concentrated hydrochloric acid to leach tin removal residue can not meet the requirements of indium leaching,and part of tin is leached into the solution during the process,which cannot realize the complete separation of indium and tin.If alkaline leaching approach is adopted,when the reaction temperature is controlled at 90℃,the liquid to solid ratio at 3∶1,the reaction duration at 2 h and amount of sodium hydroxide added at 100 g/L or more,80%of tin can be separated from tin removal residue and enters the solution,and indium is basically not react with sodium hydroxide and remains in slag,thus realizing the complete separation of indium and tin.