Wang Yifeng, Goikolea Eider, Ruiz de Larramendi Idoia, Reyes Efraím, Lanceros-Méndez Senentxu, Zhang Qi
BCMaterials, Basque Center for Materials, Applications and Nanostructures, UPV/EHU Science Park, 48940 Leioa, Spain.
Organic and Inorganic Chemistry Department, Faculty of Science and Technology, University of the Basque Country UPV/EHU, 48940 Leioa, Spain.
Waste Manag. 2023 Sep 7;171:271-280. doi: 10.1016/j.wasman.2023.08.047.
With the aim of achieving carbon neutrality, new policies to promote electric vehicle (EV) deployment have been announced in various countries. As EV sales gain market-share, the demand for batteries is growing very rapidly, and this has raised concerns about the raw-material supply. Therefore, efficient and environmentally friendly recycling methods for lithium-ion batteries (LIBs) are mandatory to properly implement circular economy paradigms in this field. Hydrometallurgical recycling methods are characterized by their selectivity, high product purity as well as low energy consumption. In order to accomplish a close-loop recycling method, in this work we propose the use of a deep eutectic solvent (DES) and alginate hydrogels as leaching reagent and adsorbent, respectively, for their reusability, availability and biodegradability. The solubility and thermal stability of a choline chloride-ethylene glycol based DES (choline chloride: ethylene glycol = 1:2) were investigated, 180 °C being regarded as the temperature threshold for this DES, and reaching up to 1.12gL solubility after 8 h leaching. Moreover, the DES can be reused after the eutectic state recreation with a performance over 80% with respect to the pristine DES. Calcium cross-linked sodium alginate hydrogels, which were immersed in ethylene glycol and dehydrated afterwards, were able to extract cobalt from the leachate with an efficiency of 92%. The aforementioned hydrogels can be reused after desorption and reach 91% of the performance of the pristine ones. The DES together with alginate hydrogel brings therefore a highly efficient and reusable close-loop recycling method.
为了实现碳中和，各国纷纷出台新政策以促进电动汽车（EV）的部署。随着电动汽车销量获得市场份额，对电池的需求增长非常迅速，这引发了对原材料供应的担忧。因此，锂离子电池（LIBs）高效且环保的回收方法对于在该领域正确实施循环经济模式至关重要。湿法冶金回收方法具有选择性高、产品纯度高以及能耗低的特点。为了实现闭环回收方法，在本工作中，我们分别提出使用深共晶溶剂（DES）和藻酸盐水凝胶作为浸出试剂和吸附剂，因为它们具有可重复使用性、可得性和生物降解性。研究了基于氯化胆碱 - 乙二醇的DES（氯化胆碱：乙二醇 = 1:2）的溶解度和热稳定性，180°C被视为该DES的温度阈值，浸出8小时后溶解度达到1.12gL。此外，在共晶状态恢复后，DES可以重复使用，相对于原始DES，性能超过80%。将钙交联的海藻酸钠水凝胶浸入乙二醇中然后脱水，能够从浸出液中提取钴，效率为92%。上述水凝胶在解吸后可以重复使用，性能达到原始水凝胶的91%。因此，DES与藻酸盐水凝胶一起带来了一种高效且可重复使用的闭环回收方法。
