Preferential Lithium Recovery and Temperature-Regulated Stepwise Desorption of Transition Metals from Simulated Spent NCM111 Leachate Using NaA Zeolite

Recycling spent lithium-ion batteries (LIBs) is critical for resource sustainability and carbon neutrality. This work presents a green strategy in which NaA zeolite is used to preferentially recover lithium from leachate of spent NCM111 batteries, combined with temperature-regulated stepwise separation of transition metals. Benefiting from the distinct hydrated ionic radii and charge density between Li+ and divalent metal ions, NaA zeolite selectively adsorbs Ni2+, Co2+ and Mn2+, leaving Li+ in the raffinate. Under optimized conditions, two-stage adsorption achieves 95.6%, 96.7% and 99.7% removal of Ni2+, Co2+ and Mn2+, respectively, with 11% Li+ co-adsorption. Thermodynamic analysis reveals that the adsorption process is endothermic and thermodynamically spontaneous. The interaction strength between metal ions and NaA zeolite follows the order Ni2+ > Co2+ > Mn2+, and ion exchange is identified as the dominant mechanism. It is determined that 96.8% of Mn2+ can be recovered at 0 °C, followed by the desorption of 93.5% of Co2+ at 90 °C, and the sequential separation of Mn, Co and Ni is realized. Three consecutive adsorption–desorption cycles demonstrate the acceptable reusability of the Ni-loaded NaA adsorbent. High-purity Li2CO3 (purity 96.7%, yield 93.5%), MnO2 (purity 99.3%, yield 98.4%) and Co3O4 (purity 98.8%, yield 97.6%) are obtained from the corresponding solutions. This approach provides a scalable closed-loop pathway for full-component recovery of valuable metals from spent LIBs.