Zhou Zhicun, Lei Fan, Dai Mingzhu, Zheng Fan, Qiao Yuanlu, Chang Jun, Bai Huiping, Wang Shixiong, Yang Xiangjun
Research Center of Lake Restoration Technology Engineering for Universities of Yunnan Province, School of Chemical Science and Technology, School of Materials and Energy, Yunnan University, No. 2, Cuihu North Road, Kunming 650091, China.
College of Material and Chemical Engineering, Tongren University, Tongren, Guizhou, China.
J Hazard Mater. 2025 Sep 15;496:139224. doi: 10.1016/j.jhazmat.2025.139224. Epub 2025 Jul 12.
The eco-friendly recovery of strategic metals from spent lithium-ion batteries is pivotal for realizing circular economy goals. This study introduces a low-viscosity hydrated deep eutectic solvent (DES) composed of citric acid (CA) and choline chloride (ChCl) for the efficient extraction of crucial metals from spent LiNiCoMnO (NCM) cathodes. The leaching parameters were optimized within response surface methodology (RSM), and maximum extraction efficiencies of 97.75 % Li, 99.57 % Co, 99.91 % Ni, and 99.56 % Mn were achieved under the optimal conditions. Kinetic analysis revealed extraction mechanisms controlled by surface reactions. The DES maintained high leaching efficiency over multiple recycling cycles, confirming its excellent reusability. A sequential separation strategy was developed to integrate the co-precipitation of Ni-Co-Mn oxalates followed by selective Li oxalate recovery, enabling the regeneration of high-purity ternary cathode precursors via oxalate-mediated crystallization. Density functional theory (DFT) calculations provided atomic-scale insights into the coordination interactions between the multivalent metal ions and DES functional groups. This process significantly reduces hazardous chemical consumption while maintaining cost-effectiveness throughout the recovery workflow. These findings validate the potential of this DES system for scalable, sustainable industrial applications in critical metal recycling from spent LIB cathodes.
从废旧锂离子电池中对战略性金属进行生态友好型回收，对于实现循环经济目标至关重要。本研究引入了一种由柠檬酸（CA）和氯化胆碱（ChCl）组成的低粘度水合深共熔溶剂（DES），用于从废旧LiNiCoMnO（NCM）阴极中高效提取关键金属。在响应面方法（RSM）内对浸出参数进行了优化，在最佳条件下实现了锂的最大提取效率为97.75%、钴为99.57%、镍为99.91%、锰为99.56%。动力学分析揭示了由表面反应控制的提取机制。该DES在多个循环周期中保持了较高的浸出效率，证实了其优异的可重复使用性。开发了一种顺序分离策略，将镍钴锰草酸盐的共沉淀与选择性草酸锂回收相结合，通过草酸盐介导的结晶实现高纯度三元阴极前驱体的再生。密度泛函理论（DFT）计算提供了关于多价金属离子与DES官能团之间配位相互作用的原子尺度见解。该过程显著减少了有害化学品的消耗，同时在整个回收工作流程中保持了成本效益。这些发现验证了该DES系统在从废旧LIB阴极回收关键金属方面进行可扩展、可持续工业应用的潜力。
