Extraction of lithium from salt lake brine with tributyl phosphate and an ionic liquid

Abstract

Solvent extraction of lithium (Li) from salt lake brine was investigated by employing tributyl phosphate (TBP) and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMI-TFSI). High extraction efficiency of Li was obtained from the brine containing co-existed metals. The extraction of Li was proceeded by solvation of Li with TBP followed by cation exchange with the ionic liquid. The purity of Li was increased to 85.1% after two extraction - stripping processes of the present extraction system.