硫酸肼还原酸浸出废旧锂离子电池中的有价金属

Reductive acid leaching of valuable metals from spent lithium-ion batteries using hydrazine sulfate as reductant

采用硫酸肼作为锂、镍、钴和锰从废锂离子电池中浸出时的还原剂,结合条件实验对浸出机理和浸出动力学进行研究。在最优条件:硫酸2.0 mol/L、硫酸肼30 g/L、固液比50 g/L、温度80℃和浸出时间60 min下,97%的Li、96%的Ni、95%的Co以及86%的Mn被浸出。通过浸出动力学分析得出Li、Ni以及Co的浸出活化能分别为44.32、59.37和55.62 k J/mol,表明浸出过程受化学反应控制。XRD和SEM-EDS分析结果表明,浸出渣的主要组成为MnO2。上述研究结果表明,硫酸肼可作为废锂离子电池中有价金属浸出的有效还原剂。

Hydrazine sulfate was used as a reducing agent for the leaching of Li,Ni,Co and Mn from spent lithium-ion batteries.The effects of the reaction conditions on the leaching mechanism and kinetics were characterized and examined.97%of the available Li,96%of the available Ni,95%of the available Co,and 86%of the available Mn are extracted under the following optimized conditions:sulfuric acid concentration of 2.0 mol/L,hydrazine sulfate dosage of 30 g/L,solid-to-liquid ratio of 50 g/L,temperature of 80℃,and leaching time of 60 min.The activation energies of the leaching are determined to be 44.32,59.37 and 55.62 k J/mol for Li,Ni and Co,respectively.By performing X-ray diffraction and scanning electron microscopy in conjunction with energy dispersive X-ray spectroscopy,it is confirmed that the main phase in the leaching residue is MnO2.The results show that hydrazine sulfate is an effective reducing agent in the acid leaching process for spent lithium-ion batteries.