Key Laboratory of Coal Processing and Efficient Utilization (Ministry of Education), School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, China.
Key Laboratory of Coal Processing and Efficient Utilization (Ministry of Education), School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, China.
Waste Manag. 2024 Jul 15;184:120-131. doi: 10.1016/j.wasman.2024.05.039. Epub 2024 May 29.
The recycling of spent lithium-ion batteries (LIBs) can not only reduce the potential harm caused by solid waste piles to the local environment but also provide raw materials for manufacturing new batteries. Flotation is an alternative approach to achieve the selective separation of cathode and anode active materials from spent LIBs. However, the presence of organic binder on the surface of hydrophilic lithium transition-metal oxides results in losses of cathode materials in the froth phase. In this study, plasma treatment was utilized to remove organic layers from cathode and anode active materials. Firstly, the correlations between plasma treatment parameters (e.g., input power, air flowrate, and treatment time) were explored and the contact angles of cathode and anode active materials were investigated by the response surface methodology. Secondly, differences in the flotation recoveries of cathode and anode active materials were enhanced with plasma modification prior to flotation, which is consistent with the contact angle measurement. Finally, the plasma-modification mechanisms of hydrophobicity of cathode and anode active materials were discussed according to Fourier Transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses. The proposed method could be a promising tool to enhance the flotation separation efficiency of cathode and anode active materials for the recycling of spent LIBs.
从废旧锂离子电池（LIBs）中回收不仅可以减少固体废物堆对当地环境造成的潜在危害，还可以为制造新电池提供原材料。浮选是一种从废旧 LIBs 中选择性分离阴极和阳极活性材料的替代方法。然而，亲水锂过渡金属氧化物表面的有机粘结剂会导致阴极材料在泡沫相中损失。在本研究中，利用等离子体处理去除阴极和阳极活性材料表面的有机层。首先，通过响应面法探讨了等离子体处理参数（如输入功率、空气流量和处理时间）之间的相关性，并研究了阴极和阳极活性材料的接触角。其次，在浮选前进行等离子体改性可以增强阴极和阳极活性材料的浮选回收率差异，这与接触角测量结果一致。最后，根据傅里叶变换红外光谱（FTIR）和 X 射线光电子能谱（XPS）分析讨论了阴极和阳极活性材料疏水性的等离子体改性机理。该方法有望成为提高废旧 LIBs 回收中阴极和阳极活性材料浮选分离效率的一种有前途的工具。
