橙皮还原浸出废旧锂电池正极材料有价金属

Reduction leaching of valuable metals from spent cathode materials of lithium batteries using orange peel

为了促进废旧锂电池的高效环保浸出,研究了一种利用橙皮作为有机还原剂,高效浸出废旧锂电池正极材料中金属的方法。结果表明:橙皮的添加显著提高了柠檬酸浸出剂的性能,实现了锂、镍、钴和锰的高浸出率,最佳浸出条件为柠檬酸浓度2 mol/L、橙皮用量40 g/L、浸出温度95℃、液固比20∶1、搅拌速度300 r/min、浸出时间120 min。利用Design Expert 10推导出了一个浸出模型,能精确预测金属的浸出率。动力学研究表明,锂、镍、钴和锰的表观活化能分别为64.95、67.71、66.65和72.8 kJ/mol,说明正极材料浸出过程主要受化学反应控制。通过对比OP浸出前后的SEM像,验证了橙皮还原能力可用还原糖理论进行解释。

In order to promote the efficient and environmentally friendly leaching of spent lithium-ion batteries,a method utilizing orange peel as an organic reducing agent was studied for the efficient leaching of metals from the cathode materials of spent lithium-ion batteries.The results indicate that the addition of orange peel significantly enhances the performance of citric acid leaching agent,achieving high leaching rates of lithium,nickel,cobalt and manganese.The optimal leaching conditions are determined as follows:citric acid concentration of 2 mol/L,orange peel dosage of 40 g/L,leaching temperature of 95℃,L/S ratio of 20∶1,stirring speed of 300 r/min,and leaching time of 120 min.A leaching model is derived using Design Expert 10,which accurately predicts the leaching rates of metals.Kinetic studies reveal that the apparent activation energies for lithium,nickel,cobalt and manganese are 64.95,67.71,66.65 and 72.8 kJ/mol,respectively,indicating that the leaching process of cathode materials is mainly controlled by chemical reaction.By comparing SEM images before and after OP leaching,the reduction capability of orange peel is validated and can be explained using the theory of reducing sugars.