中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 34 No. 4 April 2024 |
（1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. Key Laboratory of Metallurgical Separation Science and Engineering in Nonferrous Industry, Central South University, Changsha 410083, China;
3. State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha 410018, China;
4. Hunan Provincial Key Laboratory of Oils and Fats Molecular Structure and Function, Hunan Academy of Forestry, Changsha 410018, China）
Abstract:A synergistic solvent extraction (SSX) system consisting of tung oil-based carboxylic acid (TFCA) and isonicotinic acid ester (4PC) was proposed to selectively extract Ni over Li and Mg from acid leach solutions of spent lithium-ion batteries (LIBs). The SSX system indicates a synergistic effect of Ni which can be mainly attributed to the multiple chelate ring structure formed between TFCA and Ni, therefore resulting in strong selectivity of Ni. With optimal conditions, the extraction of Ni reaches 97.3% in a single stage, while the extractions of Mg and Li are nil and 2.29%, respectively. Further, after scrubbing with 300 mg/L NiSO4, the loaded organic solution is stripped using 0.2 mol/L H2SO4. The strip liquor containing 11.52 g/L Ni and only less than 6 mg/L Li is obtained.
Key words: tung oil; carboxylic acid extractant; synergistic solvent extraction; nickel; extraction mechanism
