Selective Electrochemical Li⁺ Extraction from Brines Using TiP₂O₇

The demand for Li keeps increasing due to the growing need for Li-ion batteries (LIBs). More than 50% of Li is currently obtained from Li+-rich brine deposits. Also, the LIB manufacturing industry generates wastewater containing Li+ mixed with other cations. Thus, the development of methods to selectively extract Li+ from various natural and industrial Li+-containing solutions are critically needed to ensure a sustainable and environmentally benign Li supply chain. This study reports TiP2O7 (TPO) as a promising candidate for selective electrochemical Li+ extraction and recovery from solutions containing a mixture of cations where Na+, K+, Mg2+, and Ca2+ are more concentrated than Li+. In addition, TPO's ability to extract Li+ from a simulated brine mimicking the Uyuni Brine in Bolivia and recovering it as Li2CO3 is demonstrated. Its unique advantage over LiFePO4 and LiMn2O4, two candidates previously investigated for selective Li+ extraction from brines, is also discussed.