酒石酸浸出钴酸锂动力学机理研究

KINETIC MECHANISM OF LEACHING LITHIUM COBALT OXIDES USING TARTARIC ACID

提出了一种绿色回收废旧钴酸锂电池正极活性物质的方法。采用酒石酸为浸出剂和还原剂,湿法回收废旧钴酸锂电池中的钴和锂。结果表明:钴酸锂与酒石酸摩尔比为1∶4,反应固液比为15 g/L,反应温度为90℃,反应时间为5 h时,金属钴和锂的浸出率分别为92.95%、91.86%;动力学分析显示,Co、Li浸出反应利用经典模型拟合效果最佳,其表观活化能分别为55.20,63.65 kJ/mol,浸出过程属于吸热反应和化学反应控制。该工艺可实现废旧钴酸锂正极活性物质的高效绿色回收,为其他废旧锂离子电池的回收提供理论基础。

This research proposed a green method for recovering positive active substances from spent lithium cobalt oxide batteries, used tartaric acid as the leaching agent and reducing agent to recover cobalt and lithium. The results showed that the leaching rates of cobalt and lithium were 92.95% and 91.86% respectively, when the molar ratio of lithium cobalt oxide to tartaric acid was 1∶4, the solid-liquid ratio was 15 g/L, the reaction temperature was 90 ℃ and the reaction time was 5 h. Kinetic analysis showed that the leaching reactions of Co and Li could be fitted best by the classical model. And their apparent activation energies were 55.20 kJ/mol and 63.65 kJ/mol respectively, which belonged to endothermic reaction and chemical reaction control. This process can achieve the efficient and green way by recovering waste lithium cobalt oxide cathode materials, and provide a theoretical basis for the recovery of other waste lithium-ion batteries.