Recovery Of Lithium From Salt Lake Brine By Ion Exchange Resin

Lithium and lithium containing compounds play very important role in modern industries, and there are rich lithium resources in salt lakes in China. In this study, the related issues of recovering lithium ion from salt lake brine by ion exchange resin were detailed investigated.In the static adsorption experiment, effects of several parameters were investigated. The results indicate that the adsorption equilibrium was reached within 1 hour; higher temperature, rotating speed and pH value were beneficial to the adsorption; the Li+ adsorption capacity increased with increased initial concentration, and tended to equilibrate at last. Dynamic adsorption results show that higher temperature and lower flow rate were beneficial, and the resin had good regenerated performance. The adsorption isotherm had Langmuir monolayer adsorption characteristics, the adsorption rate could be well described by second-order kinetic equation, and film diffusion was the rate-determining step. Two different scaled dynamic operations could handle large volume feed liquid, lithium ion could be eluted completely with small eluent amount, and the elution efficiency was fast.When other metal ions exist in the solution, Li+ adsorption capacity reduced. Dynamic experimental results reveale that Li+ and Mg2+ could be separated by controlling the feed liquid volume, in order to make the export fluid contain Li+ only, while Mg2+ was adsorbed to the resin phase. The modified phenolic resin was synthesized via molecular imprinting technology, using Li+ as the template molecule. When the solution contained both Li+ and Mg+, the distribution coefficient of Li+ was higher than that of Mg2+, indicate that the modified resin could adsorb Li+ selectively.