Recovery of Lithium Ion From Exchanged Mother Liquids of Li-LSX Zeolite-Part 1: Research on the Extraction Process

In order to recover Lithium ion from exchanged mother liquids of Li-LSX zeolite,an extraction method of lithium ion by use of tri-n-butyl phosphate(TPB) with 200^# gasoline as mixed solvent was investigated in the presence of ferric chloride as cooperation agent.Effects of procedure parameters,such as contact time,phase ratio,hydrochloric acid acidity,temperature,concentration of extractant,the ratio of c(Fe³⁺) /c(Li⁺) and concentration of MgCl₂,on the extraction technology were analyzed in details.The results show that TBP solvent is a very suitable extractant to lithium ion and the extraction rate can reach up to 85%.The optimal extraction conditions at room temperature are found as the following: c(Fe³⁺) /c(Li⁺) ratio is around 4;concentration of MgCl₂ solution is 3~4 mol/L.TBP volume fraction is 40~60%.Contact time is during the period of 10~15 min.pH value is around 2~3.And phase ratio is about 1∶1.