Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6659219 | Hydrometallurgy | 2016 | 10 Pages |
Abstract
A green liquid-liquid extraction (LLE) system was developed for the recovery of lithium (Li+) from sodium and potassium ions, which are typically present at high concentrations in seawater. Dibenzo-14-crown-4ether (DB14C4) was functionalized with a long lipophilic alkyl C18 chain and a pendent proton ionizable carboxylic acid group to obtain a lithium (Li+) carrier system (DB14C4-C18-COOH) with high Li+ extraction performance and good stability in the room temperature ionic liquid diluent, CYPHOSIL 109. The Li+ extraction efficiency of DB14C4-C18-COOH/CYPHOSIL 109 can be enhanced by increasing the solution pH and DB14C4-C18-COOH concentration. Further examination of extraction results reveal 1:1 coordination between DB14C4-C18-COOH and Li+ which was also supported by density functional theory calculations. At room temperature, the developed LLE system effectively extracted dilute Li+ from Na+ (selectivity αLi+/Na+ = 1954) and K+ (αLi+/K+ = 138). Kinetic and thermodynamic parameters were evaluated for optimum Li+ extraction conditions. Sequestered Li+ can be easily recovered from the LLE system using dilute hydrochloric acid. Results from recycling tests showed stable Li+ extraction performance hence it can be used for long term application. Overall results indicate the potential application of DB14C4-C18-COOH/CYPHOSIL 109 as a treatment step to recover Li+ from brine or seawater.
Keywords
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Chemical Engineering (General)
Authors
Rey Eliseo C. Torrejos, Grace M. Nisola, Ho Seong Song, Jeong Woo Han, Chosel P. Lawagon, Jeong Gil Seo, Sangho Koo, Hern Kim, Wook-Jin Chung,