(Invited) Electrochemical Deionization for Water Desalination and Direct Lithium Extraction

Abstract

Electrochemical deionization based on carbonaceous and intercalation electrodes has been proposed as a promising candidate for desalinating saline water and for selectively separating toxic or valuable ionic constituents from water. In this talk, I will first introduce our work on the performance evaluation and techno-economic assessment for electrochemical desalination of brackish water. Parametric models were established to estimate the unit cost of water desalination and energy efficiency in electrochemical desalination with different configurations, and results were compared against brackish water reverse osmosis. In the second part of the talk, I will present our work on the development of selective electrochemical separation systems, focusing on the recovery of lithium from water streams. We investigated the selectivity of lithium separation in electrolyte solutions with different cation concentration ratios as well as in simulated brines. Results show that lithium chloride with a purity of >95% can be extracted from high-salinity brines in the presence of competing monovalent and divalent cations.