从酸洗废液中选择性萃取铁的研究

Study on Selective Extraction of Iron from Pickling Waste Liquid

采用离心萃取法对酸洗废液中铁进行选择性萃取实验,确定了磷酸三丁酯(TBP)-二甲苯萃取体系萃取铁的最佳工艺参数。结果表明,TBP浓度40%,VO/VA=1∶1,流量100~600 mL/min,三级离心萃取,铁的萃取率均可达到99%以上。采用0.5%盐酸溶液,经两级离心反萃,铁的反萃率可达到99%以上。同时,萃取体系对镍、锌的共萃率较低,表明磷酸三丁酯-二甲苯体系对酸洗废液中铁的萃取选择能力较高,可以达到与溶液中镍、锌有较好的分离效果。

The experiment of selective extraction of iron from pickling waste liquid is carried out by centrifugal extraction,and the optimum process parameters of iron extraction by tributyl phosphate(TBP)-xylene extraction system are determined.The results show that the extraction rate of iron can reach more than 99%with TBP concentration of 40%,VO/VA=1∶1,flow rate of 100~600 mL/min and three-stage centrifugal extraction.Using 0.5%hydrochloric acid solution and two-stage centrifugal stripping,the stripping rate of iron can reach more than 99%.At the same time,the co-extraction rate of nickel and zinc in the extraction system is low,indicating that the tributyl phosphate xylene system has high extraction selectivity for iron in pickling waste liquid,and can achieve good separation effect with nickel and zinc in the solution.