Facile synthesis of aluminum-based adsorbents from spent lithium-ion batteries for efficient Li+ extraction

The rapid growth of the electric vehicle industry is generating large quantities of spent lithium-ion batteries. However, these batteries have complex compositions, making current recycling processes inefficient at recovering valuable metals. Herein, lithium and aluminum from spent lithium-ion batteries were directly extracted and used to prepare aluminum-based lithium-ion adsorbents through a facile co-precipitation approach for the first time. This approach eliminates aluminum interference with nickel, cobalt, and manganese, simplifying the recovery of cathode materials. The developed aluminum-based lithium adsorbent displayed excellent ion selectivity and stability, with an adsorption capacity of 7.44 mg/g from a 500 mg/L lithium solution at 30℃, maintaining 96.18 % capacity after seven adsorption cycles. Additionally, this adsorption process follows pseudo-second-order kinetics and the Sips model. Cation competition experiments showed the ionic selectivity follow the sequence Li + > Mg 2+ > Na + > K + > Ca 2+ . This approach enables a one-step regeneration and utilization of lithium-aluminum resources from spent lithium-ion batteries, potentially lowering recycling costs and holds promise for large-scale applications.