Integrating recycled valuable elements from spent LiFePO4 batteries based on a dimethyl oxalate leaching system

作者：Liu, Chunli; Xu, Jianbin; Yu, Jinxiang; Hu, Jia; Liu, Pengfei; Wang, Zhongbing; Deng, Chunjian; Luo, Feng; He, Junwei; Zeng, Guisheng^*; Luo, Xubiao

来源：RESOURCES CONSERVATION AND RECYCLING, 2024, 200: 107301.

DOI：10.1016/j.resconrec.2023.107301

• Dimethyl oxalate
• Selective leaching
• Integrated recycling

Recycling of spent lithium-ion batteries (LIBs) has great significance in sustainable global development and environmental protection. In this study, a novel strategy is proposed to selectively separate and integrate valuable elements from spent LiFePO4 (SLFP) cathode materials via an eco-friendly leaching process using dimethyl oxalate. By properly regulating and controlling the leaching parameters, 99.19 % Li and 96.28 % P were leached into solution, whereas only 0.2 % Fe was dissolved. Leaching mechanism revealed that the highefficiency dissolution of the SLFP cathode materials is due to the joint action of methanol and oxalic acid derived from dimethyl oxalate hydrolysis. Furthermore, the lithium-containing leaching solution was used to prepare Li3PO4 products with a purity of 99.62 % through crystallization, and the Fe was retained in leach residue in the form of FeC2O4 & sdot;2H2O with a purity of 99.54 %. These findings provide a reliable reference for environmental protection, selective recovery, and process design of SLFP LIBs.

• 单位
  南昌航空大学