An emission-free controlled potassium pyrosulfate roasting-assisted leaching process for selective lithium recycling from spent Li-ion batteries

Chunli Liu; Haiyan Ji; Jiayin Liu; Pengfei Liu; Guisheng Zeng; Xubiao Luo; Qian Guan; Xue Mi; Yingpeng Li; Jiefei Zhang; Yongfen Tong; Zhongbing Wang; Shaolin Wu

doi:10.1016/j.wasman.2022.08.021

An emission-free controlled potassium pyrosulfate roasting-assisted leaching process for selective lithium recycling from spent Li-ion batteries

Waste Manag. 2022 Nov:153:52-60. doi: 10.1016/j.wasman.2022.08.021. Epub 2022 Aug 29.

Authors

Affiliations

¹ National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, School of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang 330063, PR China.
² School of Civil Engineering and Architecture, Nanchang Hangkong University, Nanchang 330063, PR China.
³ National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, School of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang 330063, PR China. Electronic address: zengguisheng@hotmail.com.

PMID: 36049272
DOI: 10.1016/j.wasman.2022.08.021

Abstract

Recycling critical metals from spent Li-ion batteries (LIBs) is important for the overall sustainability of future batteries. This study reports an improved sulfation roasting technology to efficiently recycle Li and Co from spent LiCoO₂ LIBs using potassium pyrosulfate as sulfurizing reagent. By sulfation roasting, LiCoO₂ was converted into water-soluble lithium potassium sulfate and water-insoluble cobalt oxide. Under optimal conditions, 98.51% Li was leached in water, with a selectivity of 99.86%. More importantly, sulfur can be recirculated thoroughly, and the sulfur atomic efficiency can be significantly enhanced by controlling the amount of potassium pyrosulfate. Li ions from the water leaching process were recovered by chemical precipitation. Furthermore, application of this technology to other spent LIBs, such as LiMn₂O₄ and LiNi_0.5Co_0.2Mn_0.3O₂, verified its effectiveness for selective recovery Li. These findings can provide some inspiration for high efficiency and environmentally friendly recovery metal from spent LIBs.

Keywords: Potassium pyrosulfate; Roasting; Selective recovery; Spent Li-ion batteries.