离心萃取制备电池级硫酸锰

Preparation of battery grade manganese sulfate by centrifugal extraction

电池级硫酸锰可采用溶剂萃取法制备,目前在实验室研究阶段,通过在分液漏斗中混合、摇匀、静置分离,测试结果受操作因素的影响较大,与工业化应用生产存在差距。针对传统工业萃取设备反应釜、萃取槽存在的问题,采用离心萃取机,通过离心萃取、离心洗涤、离心反萃工艺流程制备电池级硫酸锰。在料液Mn浓度为29.51 g/L,萃取相比O/A为2.0∶1.0时,4级离心萃取Mn的萃取率为75%~81%;提高萃取O/A相比至3.0∶1.0,Mn的萃取率达到98%;再经过4级离心洗涤、3级离心反萃,得到的反萃液中Mn^(2+)浓度为9.16 g/L,Mg^(2+)、Ca^(2+)浓度分别降至3.34 mg/L、2.19 mg/L,达到电池级硫酸锰的指标,全过程Mn的回收率达到93.12%,Mg^(2+)、Ca^(2+)去除率分别为99.75%、99.59%。

Battery-grade manganese sulfate could be prepared by solvent extraction method,which was currently in laboratory research stage.Through mixing,shaking and static separation in the separation funnel,the test results were greatly influenced by the operational factors,there was a gap between industrial application.In view of the problems of traditional extraction equipment such as reaction kettle and extraction tank,the battery grade manganese sulfate was prepared by centrifugal extraction,centrifugal washing and back extraction using centrifugal extractor.When the concentration of manganese in the feed solution was 29.51 g/L and the extraction ratio O/A was 2.0∶1.0,the extraction rate of Mn by 4-stage centrifugal extraction was 75%-81%.By increasing the extraction O/A ratio to 3.0∶1.0,the extraction rate of Mn reached 98%.After 4-stage centrifugal washing and 3-stage back extraction,the concentration of Mn~(2+) in the strip liquor was 9.16 g/L,the concentration of Mg~(2+) and Ca~(2+) was reduced to 3.34 mg/L and 2.19 mg/L respectively,meeting the index of battery grade manganese sulfate.The recovery rate of Mn in the whole process reached 93.12%,the removal rate of Mg~(2+) and Ca~(2+) was 99.75% and 99.59% respectively.