标题: Revealing role of oxidation in recycling spent lithium iron phosphate through acid leaching

作者: Wang, DF (Wang, Dan-Feng); Chen, M (Chen, Min); Zhao, JJ (Zhao, Jing-Jing); Zhou, FY (Zhou, Feng-Yin); Wang, HY (Wang, Hong-Ya); Qu, X (Qu, Xin); Cai, YQ (Cai, Yu-Qi); Zheng, ZY (Zheng, Zhi-Yu); Wang, DH (Wang, Di-Hua); Yin, HY (Yin, Hua-Yi)

来源出版物: RARE METALS  DOI: 10.1007/s12598-024-03007-x  Early Access Date: NOV 2024  Published Date: 2024 NOV 8  

摘要: The efficient recycling of spent lithium iron phosphate (LiFePO4, also referred to as LFP) should convert Fe (II) to Fe (III), which is key to the extraction of Li and separation of Fe and is not well understood. Herein, we systematically study the oxidation of LiFePO4 in the air and in the solution containing oxidants such as H2O2 and the effect of oxidation on the leaching behaviors of LFP. In the air, O2 breaks down the LFP olivine structure at 550 degrees C for 1 h by oxidizing Fe (II) to Fe (III) in terms of converting LFP to Li3Fe2(PO4)3 and Fe2O3. After that, Li is leached in 0.5 M sulfuric acid solution and is further recycled as Li3PO4 with a Li recovery efficiency of 97.48%. Meanwhile, Fe is recovered as FePO4 and Fe2O3. Compared with H2SO4-H2O2, the air oxidation saves H2O2 but increases the leaching efficiency of Fe and H2SO4 consumption. The discrepancy of Fe leaching efficiency can be attributed to the different leaching mechanisms involving the solid-to-solid and solid-to-liquid-to-solid conversions. Furthermore, the results of the Everbatt model analysis show that the air roasting-H2SO4 leaching method has low emission and potentially high income, which is simple and safe. Overall, this work will deepen the understanding of acid leaching of LFP and favorably stimulate the maturation of the LFP recycling technique.

作者关键词: Spent lithium iron phosphate battery; Air roasting; Acid leaching; Oxidation; Recovery

地址: [Wang, Dan-Feng; Zhao, Jing-Jing; Zhou, Feng-Yin; Wang, Hong-Ya; Qu, Xin; Cai, Yu-Qi; Zheng, Zhi-Yu; Wang, Di-Hua; Yin, Hua-Yi] Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430072, Peoples R China.

[Chen, Min] China Urban Rural Holdings Grp CO Ltd, Wuhan 430051, Peoples R China.

[Wang, Di-Hua; Yin, Hua-Yi] Hubei Int Sci & Technol Cooperat Base Sustainable, Wuhan 430072, Peoples R China.

通讯作者地址: Yin, HY (通讯作者)，Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430072, Peoples R China.

Yin, HY (通讯作者)，Hubei Int Sci & Technol Cooperat Base Sustainable, Wuhan 430072, Peoples R China.

电子邮件地址: yinhuayi@whu.edu.cn

影响因子：9.6