Adsorbents for lithium extraction from salt lake brine with high magnesium/lithium ratio: From structure-performance relationship to industrial applications

Driven by technology advancement and wide application of lithium, the market demand for lithium is skyrocketing. To enable the sustainable supply of lithium, it is strongly desirable to extract lithium from various resources, especially salt lake brine with 60% of global lithium content. Recently, adsorption has served as a critical procedure for selective lithium extraction from brines, in particular those with high Mg2+/Li+ ratios. Herein, a comprehensive review of lithium adsorbents from nano structural and compositional effects to industrial applications is performed. Firstly, lithium adsorbents are fully summarized, involving the common types, structure-performance relationships, lithium intercalation and deintercalation mechanisms at the ionic level, and current limitations of various adsorbents. Based on these summaries, a performance heatmap is created to visualize the performance of lithium adsorbents. To serve the industrial demands, the shaping techniques and factors influencing extraction properties are then discussed. Further, the industrial cases of different lithium adsorbents and universal strategies of lithium extraction from brines to Li2CO3 products using adsorbents are demonstrated, providing technical references for industrial applications. Finally, recommendations and perspectives on larger-scale development of lithium adsorbents are proposed. Overall, this review not only offers in-depth insight into lithium extraction from brines with high Mg2+/Li+ ratios, but also inspires the development and design of next-generation lithium adsorbents with unprecedented properties.