Jirattisak Julalak, Imyim Apichat, Bhawawet Nakara
Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand; Center of Excellence on Petrochemical and Materials Technology, Chulalongkorn University, Bangkok, 10330, Thailand.
Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Chemosphere. 2025 Sep;385:144556. doi: 10.1016/j.chemosphere.2025.144556. Epub 2025 Jul 10.
The growing demand for lithium-ion batteries (LIBs) in electronic devices and electric vehicles has led to an increase in spent LIB waste, posing environmental risks and exacerbating concerns over lithium resource depletion. Traditional recycling methods often rely on toxic organic solvents, highlighting the urgent need for safer, more sustainable alternatives. In this study, a novel task-specific deep eutectic solvent (DES) composed of dibenzoylmethane (DBM) and trioctylphosphine oxide (TOPO) in a 1:1 molar ratio was developed for selective lithium extraction. Unlike conventional DESs, the DBM/TOPO-DES is hydrophobic, enabling efficient liquid-liquid extraction by minimizing miscibility with aqueous solutions. Under optimized conditions-pH 12, 30 s of vortexing, room temperature, and a 2:1 aqueous-to-DES phase ratio-the system achieved over 99% lithium extraction efficiency. It also exhibited high extraction efficiency with EDTA as a masking agent for lithium in the presence of commonly co-existing ions such as Co(II), Cu(II), and Ni(II), typically present in LIB cathode materials. Lithium was efficiently back-extracted using 0.7 M HCl, and the DES maintained excellent performance across five extraction cycles, demonstrating its reusability. Compared to other DES-based approaches, this system combines rapid kinetics, high extraction efficiency, and a greener profile without compromising performance. Thermal analysis, phase behavior, and spectroscopic characterization confirmed the stability and formation of the DES. Overall, the DBM/TOPO-DES offers a sustainable and effective alternative to traditional solvent systems, advancing green chemistry principles and contributing to the efficient recovery of critical lithium resources from spent batteries.
电子设备和电动汽车对锂离子电池（LIBs）的需求不断增长，导致废旧LIBs废弃物增加，带来环境风险并加剧对锂资源枯竭的担忧。传统回收方法通常依赖有毒有机溶剂，凸显了对更安全、更可持续替代方法的迫切需求。在本研究中，开发了一种新型的特定任务型深共熔溶剂（DES），其由二苯甲酰甲烷（DBM）和三辛基氧化膦（TOPO）以1:1摩尔比组成，用于选择性锂提取。与传统DESs不同，DBM/TOPO-DES具有疏水性，通过最小化与水溶液的混溶性实现高效液-液萃取。在优化条件下（pH 12、涡旋30秒、室温以及水相与DES相的比例为2:1），该系统实现了超过99%的锂提取效率。在LIB正极材料中通常共存的离子如Co(II)、Cu(II)和Ni(II)存在的情况下，以EDTA作为锂的掩蔽剂时，它也表现出高提取效率。使用0.7 M HCl可有效地将锂反萃取出来，并且DES在五个提取循环中均保持优异性能，证明了其可重复使用性。与其他基于DES的方法相比，该系统结合了快速动力学、高提取效率以及更环保的特性，且不影响性能。热分析、相行为和光谱表征证实了DES的稳定性和形成。总体而言，DBM/TOPO-DES为传统溶剂系统提供了一种可持续且有效的替代方案，推进了绿色化学原则，并有助于从废旧电池中高效回收关键锂资源。
