Pilot-scale demonstration of an electrochemical system for lithium recovery from the desalination concentrate

The rapidly growing interest in seawater desalination has drawn a large pool of attention among the industry for proper management of its by-product; desalination concentrate. Among the various attempts to utilize desalination concentrate, the selective extraction of lithium has received considerable attention as the industrial demand for lithium becomes higher than ever. In this study, using lithium-ion battery electrode materials that enable highly selective electrochemical capture and release of lithium, we report a pilot-scale system designed for the treatment of actual desalination concentrate produced by a desalination plant. This system, equipped with λ-MnO₂ and Ag electrodes, enabled lithium recovery from 6 tons of desalination concentrate per day (0.25 ton per hour), leading the production of a solution containing 62 mM of Li⁺ with purity and enrichment factor of 88% and 1800, respectively.