As demand for electric vehicles, grid-scale batteries, and renewable energy storage accelerates, lithium supply has become a critical constraint. In new research led by Ngai Yin Yip at the Columbia University School of Engineering and Applied Science, engineers describe a lithium extraction method that could significantly expand accessible reserves while reducing the environmental footprint associated with current production techniques.
Dach, E., Marston, J., Abu-Obaid, S., Peng, A., & Yip, N. Y. (2026). A novel approach for direct lithium extraction from alkali metal cations in brine mixtures using thermally switchable solvents. Joule, 102265. https://doi.org/10.1016/j.joule.2025.102265
The study addresses a core limitation of today’s lithium supply chain. While lithium is relatively abundant, much of it exists in low-grade brines that are difficult to process using established methods. Solar evaporation, which dominates brine-based lithium production, relies on vast evaporation ponds and long processing times that can stretch up to two years. These operations require large amounts of land and water, often in arid regions where both are scarce.
Ngai Yin Yip at the Columbia University School of Engineering and Applied Science stated,
“This is a new way to do direct lithium extraction. It’s fast, selective, and easy to scale. And it can be powered by low-grade heat from waste sources or solar collectors.”
Yip and his colleagues propose an alternative approach known as switchable solvent selective extraction, or S3E. Rather than concentrating lithium by evaporating water, the method uses a temperature-responsive solvent to selectively pull lithium ions directly from brine mixtures. The solvent’s behavior changes with heat, allowing lithium to be captured at one temperature and released at another, after which the solvent can be reused.
A key challenge in lithium extraction is selectivity. Brines typically contain high concentrations of sodium, potassium, magnesium, and other ions that interfere with recovery. In laboratory tests, the S3E process showed a strong preference for lithium, achieving selectivity ratios up to ten times higher than sodium and more than twelve times higher than potassium. Magnesium, a particularly problematic contaminant, was removed through a controlled precipitation step triggered within the process.
The research team evaluated the method using synthetic brines designed to replicate conditions at California’s Salton Sea, a geothermal region believed to contain enough lithium to supply hundreds of millions of electric vehicle batteries. Over multiple extraction cycles using the same solvent batch, the system recovered a substantial fraction of the available lithium, suggesting a path toward continuous operation rather than one-off batch processing.
Unlike many direct lithium extraction techniques, S3E does not rely on solid sorbents or extensive downstream purification. The process instead exploits differences in how lithium ions interact with surrounding water molecules within the solvent system. Heating the solvent releases lithium into a more concentrated, purified stream, while regenerating the solvent for reuse. According to the researchers, the temperature swings required could be supplied by low-grade waste heat or solar thermal systems, further reducing energy demands.
The findings were published in the journal Joule and align with a broader push across academia and industry to move away from evaporation ponds and hard-rock mining. Both dominant approaches carry significant environmental costs, including habitat disruption, water depletion, and chemical waste generation.
While the work remains at a proof-of-concept stage, it highlights how process-level innovation could reshape access to critical minerals. The researchers note that the system has not yet been optimized for maximum yield or cost, and further development will be required before industrial deployment. Even so, the ability to extract lithium efficiently from low-concentration, contaminated brines could bring previously unusable resources into the supply mix.
As clean energy technologies scale globally, attention is increasingly turning to the sustainability of the materials that enable them. By offering a faster and potentially cleaner route to lithium recovery, the S3E approach provides one example of how engineering advances could help align mineral extraction with the goals of the energy transition, rather than working against them.
Adrian graduated with a Masters Degree (1st Class Honours) in Chemical Engineering from Chester University along with Harris. His master’s research aimed to develop a standardadised clean water oxygenation transfer procedure to test bubble diffusers that are currently used in the wastewater industry commercial market. He has also undergone placments in both US and China primarely focused within the R&D department and is an associate member of the Institute of Chemical Engineers (IChemE).
