The sorting of spent lithium-ion batteries is not complete, and the types of black powder obtained by crushing are complex, and it is difficult to recycle. In this study, dimethyl carbonate was used to extract the organic solvent cured in the black powder, and then the carbon in the black powder was combined with complex sulfate for in-situ thermal reduction and water leaching to extract Li preferentially from the black powder. The effects of extraction factors on the recovery of organic solvents and the variables on the preferential leaching of Li were systematically studied. The changes of mineral phase during roasting were analyzed by TG-DTG, XRD, XPS and SEM-EDS. After black powder was roasted at 550°C for 3 h under air atmosphere with the synergistic effect of C and inorganic salts, 85.87 % of lithium can be selectively leached at 25°C for 2 h. LiCO with high purity can be obtained. This method provides a new idea for the recovery of spent lithium-ion batteries with complex components.

中文翻译：

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原位碳热还原有机溶剂萃取并从废旧锂离子电池中优先回收锂

废旧锂离子电池分选不彻底，破碎后得到的黑色粉末种类复杂，回收难度大。本研究采用碳酸二甲酯提取黑粉中固化的有机溶剂，然后将黑粉中的碳与复合硫酸盐结合，进行原位热还原和水浸，优先从黑粉中提取锂。系统研究了萃取因素对有机溶剂回收率的影响以及各变量对锂优先浸出的影响。采用TG-DTG、XRD、XPS和SEM-EDS分析了焙烧过程中矿物相的变化。黑粉在空气气氛下550℃焙烧3h后，在C和无机盐的协同作用下，25℃2h可选择性浸出85.87%的锂。可以获得高纯度的LiCO。该方法为成分复杂的废旧锂离子电池的回收提供了新思路。