用乙酸从废锂电池电极材料中浸出有价金属试验研究

Leaching of Valuable Metals From Spent Lithium Ion Batteries Using Acetic Acid

研究了以双氧水为还原剂,用乙酸从废锂离子电池正极材料中浸出钴酸锂,考察了乙酸浓度、固液质量体积比、双氧水用量、反应温度及反应时间对钴酸锂浸出的影响。结果表明:在乙酸浓度3.5mol/L、固液体积质量比20g/L、双氧水体积分数4%、反应温度60℃、反应时间40min条件下,钴、锂浸出率分别为84.7%和97%,而铝浸出率较低,仅为6.8%;乙酸与黏结剂聚偏氟乙烯发生反应,在聚偏氟乙烯表面引入极性基团,降低了其与钴酸锂表面的黏附性,使得铝箔与活性材料分离。此工艺不仅省去了黏结剂脱除工序,还能使铝片与正极材料分离,铝箔经清洗后回收。

The leaching of LiCoO 2 in the cathode material of spent lithium ion battery was studied. The effects of acetic acid concentration,solid-to-liquid ratio,H 2O 2 concentration,temperature and reaction time on leaching of LiCoO 2 were investigated. The results indicate that under the conditions of acetic acid concentration of 3.5 mol/L,solid-to-liquid ratio of 20 g/L,H 2 O 2 concentration of 4%,reaction temperature of 60 ℃ and reaction time of 40 min,leaching of Co and Li are 84.7% and 97%, respectively .Meanwhile,the leaching rate of Al is low.When acetic acid reacts with the binder,polar groups are introduced on the surface of PVDF to improve its surface adhesion,and the aluminum foil is separated from the active material.This process not only avoids removing the binder,but also separates the Al from the cathode material,and the aluminum foil can be recycled after cleaning.