Electrodialysis Extraction of Lithium from Seawater Using Solid-State Electrolyte-on-Ceramic Membrane with High Aerial Capacity

Seawater is a promising source of lithium despite its low concentration of 0.1–0.2 ppm. While membrane-based electrodialysis shows potential for lithium extraction from seawater, its efficiency remains low. Current research is largely confined to laboratory-scale membranes, which have limited surface area and lack scalable fabrication processes for larger membranes. In this study, we developed a method for scaling up Li_0.33La_0.56TiO₃ (LLTO) on a porous ceramic membrane (SLAM 100, up to 100 × 25 cm²) for Li extraction and achieved an enrichment of 30 mg lithium per 1000 L simulated seawater with this large membrane (concentration of Li⁺: 0.21 ppm). Our membrane consists of three layers: (1) a mechanical support layer made of a ceramic porous substrate, (2) a selective, crack-free LLTO layer that facilitates lithium transport, and (3) a hydrophobic adsorption layer composed of a TiO₂ and PVDF composite, which enhances the concentration of lithium ions at the surface. This design meets three critical performance criteria: suitability for large-scale production, high lithium-to-magnesium selectivity, and efficient lithium extraction with high seawater treatment flux. We also demonstrate a solar-powered lithium extraction system based on LLTO membrane that can be potentially deployed on-site, paving the way for sustainable lithium extraction from seawater.