Membrane Permeance–Selectivity Trade-Offs in Lithium Recovery from Salt Lakes

Membrane techniques have garnered much attention for the selective separation and purification of lithium from salt lakes due to their environmental friendliness, based on a physical separation mechanism without the addition of chemicals. The urgent need to recover lithium from salt lakes is hampered by the intrinsic permeance-selectivity trade-off in membrane technologies. Despite its importance, reviews specifically focusing on this trade-off in the context of lithium harvesting remain scarce. Accordingly, this review analyzes the permeance-selectivity trade-offs of various membrane technologies in lithium recovery from salt lakes. A systematic framework is established on the basis of lithium permeance and Li+/Mg2+ selectivity, resulting in a permeance-ion/ion selectivity trade-off fundamentally distinct from the conventional permeance-water/ion trade-off. The key mechanisms, advanced theories, and modeling and simulation results for ion transport through membranes are highlighted. Furthermore, challenges and potential solutions for these membrane technologies are summarized. Future research needs to bridge the gap between the laboratory conditions and the real-world environments for lithium separation and recovery from salt lakes are suggested accordingly. This review will provide a solid basis to guide the future development of membrane technologies for selective resource separation and recovery.