Adsorption Technology for Lithium Extraction: Recent Progress and Future Perspectives

Lithium, a critical enabler of the new energy paradigm, has made its efficient recovery a strategic priority worldwide. Among direct lithium extraction (DLE) technologies, adsorption stands out for its superior Mg/Li selectivity and low energy intensity when processing salt-lake brines. This review critically surveys recent breakthroughs in inorganic ion sieves, covering anion-dependent behavior and magnetic functionalization of Li/Al-LDHs, synergistic doping-coating strategies for Mn-based sieves, and atomic-scale engineering of Ti-based systems. It further examines emerging adsorbents, including MOFs, COFs, and crown-ether hybrids, with respect to their lithium-recognition mechanisms and application potential. On this basis, the review distills key scientific bottlenecks and engineering obstacles, and outlines transformative pathways forward, notably machine-learning-assisted material design, electrochemical-adsorption integration, and recovery from ultra-dilute resources. Unlike previous reviews that focus on individual material classes, this review establishes a unified cross-category framework that links synthesis dimensions, evidence levels, performance trade-offs, and application-specific decision rules for adsorptive lithium extraction. In doing so, it aims to provide a cohesive framework for both fundamental inquiry and industrial deployment of adsorptive lithium extraction.