废旧锂电池有价金属的有机酸浸出动力学研究

Study on organic acid leaching and kinetics of valuable metals from spent lithium batteries

废旧锂电池中正极材料的湿法浸出是其有价金属回收的关键步骤之一。将废旧镍钴锰酸锂电池放电、手动拆解、煅烧得到正极粉末,研究了柠檬酸、酒石酸、抗坏血酸三种混合有机酸浸出正极材料有价金属的最佳条件:柠檬酸浓度0.8 mol/L、酒石酸浓度0.2 mol/L、抗坏血酸浓度0.3 mol/L,固液比20 g/L、搅拌速率600 r/min、反应温度70℃、反应时间120 min。在此条件下,有价金属的浸出率分别为Li:97.7%、Co:95.6%、Ni:94.6%、Mn:92.6%。用未反应收缩核模型对有机酸浸出反应进行了动力学分析,锂、钴、镍、锰的浸出反应活化能分别为30.55、46.92、42.67、49.98 kJ/mol。

Wet leaching of cathode material from spent lithium batteries is one of the key steps in the recovery process of valuable metal.In this paper,the cathode powder of nickel-cobalt-manganate battery was obtained by discharge,manual disassembly and calcination.The optimum conditions for leaching valuable metal from cathode material with citric acid,tartaric acid and ascorbic acid were studied.Under the conditions of citric acid concentration of 0.8 mol/L,tartaric acid concentration of 0.2 mol/L,ascorbic acid concentration of 0.3 mol/L,solid-liquid ratio of 20 g/L,stirring rate of 600 r/min,reaction temperature of 70℃and reaction time of 120 min,the leaching rates of valuable metals were Li:97.7%,Co:95.6%,Ni:94.6%,Mn:92.6%.The kinetic analysis of the organic acid leaching reaction was carried out using the unreacted shrinkage nuclear model.Under these conditions,the activation energies of Li,Co,Ni and Mn are 30.55、46.92、42.67、49.98 kJ/mol,respectively.