Hydrometallurgical recycling of valuable metals from spent lithium-ion batteries by reductive leaching with stannous chloride

• Published in: International journal of minerals, metallurgy and materials metallurgy and materials, 2021-06, Vol.28 (6), p.991-1000
• Main Authors: Sun, Liu-ye, Liu, Bo-rui, Wu, Tong, Wang, Guan-ge, Huang, Qing, Su, Yue-feng, Wu, Feng
• Format: Article
• Language: English
• Subjects: Acids; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Composites; Corrosion and Coatings; Electrode materials; Glass; Hydrogen peroxide; Leachates; Leaching; Lithium; Lithium-ion batteries; Maleic acid; Materials recovery; Materials Science; Metallic Materials; Metals; Natural Materials; Nickel; Organic acids; Rechargeable batteries; Recycling; Reducing agents; Surfaces and Interfaces; Thin Films; Tin chloride; Tribology
• ISSN: 1674-4799; 1869-103X
• DOI: 10.1007/s12613-020-2115-z

The reductant is a critical factor in the hydrometallurgical recycling of valuable metals from spent lithium-ion batteries (LIBs). There is limited information regarding the use of SnCl 2 as a reductant with organic acid (maleic acid) for recovering valuable metals from spent Li-CoO 2 material. In this study, the leaching efficiencies of Li and Co with 1 mol·L −1 of maleic acid and 0.3 mol·L −1 of SnCl 2 were found to be 98.67% and 97.5%, respectively, at 60°C and a reaction time of 40 min. We investigated the kinetics and thermodynamics of the leaching process in this study to better understand the mechanism of the leaching process. Based on a comparison with H 2 O 2 with respect to leaching efficiency, the optimal leaching parameters, and the activation energy, we determined that it is feasible to replace H 2 O 2 with SnCl 2 as a leaching reductant in the leaching process. In addition, when SnCl 2 is used in the acid-leaching process, Sn residue in the leachate may have a positive effect on the re-synthesis of nickel-rich cathode materials. Therefore, the results of this study provide a potential direction for the selection of reductants in the hydrometallurgical recovery of valuable metals from spent LIBs.