(中南大学 化学化工学院 有色金属资源化学教育部重点实验室，长沙 410083)
摘 要: 采用电解剥离-浸出正极材料、P204萃取除铝、秸秆硫酸浸出电池渣、草酸沉钴等工艺回收废旧锂电池中的钴。结果表明：经过20~30 min的电解剥离，实现了电池粉与铝箔的分离，钴的浸出率为50%，电流效率为70%；通过两次P204错流萃取除铝后，萃余液中Al3+含量可以降到0.4 mg/L，而钴却未损失；燕麦秸秆粉-硫酸浸出电池渣中钴的最佳工艺条件如下：硫酸2 mol/L、1 g电池渣加入0.5~0.7 g麦秆粉，固液比1:10，在80~90 ℃反应1~2 h，钴的浸出率达到98%以上；经三级浸出，COD的含量可降至1.3 g/L左右；草酸沉钴调节溶液温度为50 ℃，pH为2，保持n( )/n( )=1，1 h后钴的一次沉淀率达到92%以上，滤液pH为0.2，其滤液可作为电解浸出液循环使用。
关键字: 废旧锂电池；电解剥离；浸出；生物质酸浸；草酸钴
（College of Chemistry and Chemical Engineering, Central South University,
Key Laboratory of Nonferrous Metal Resource Chemistry, Ministry of Education, Changsha 410083, China）
Abstract:Cobalt was recycled from spent Li-ion battery through the electrolytic stripping-leaching cathode material, P204 extraction Al, straw sulphuric acid leaching battery slag and oxalate precipitating cobalt. The results show that the battery powder can be separated from aluminum foil after 20-30 min electrolytic stripping process, the cobalt leaching rate is 50% and current efficiency is 70%. After two-stage P204 cross-flow extraction, Al3+ remained in the raffinate can be dropped to 0.4 mg/L, and cobalt is not lose. Under the condition of sulfuric acid concentration 2 mol/L, adding 0.5-0.7 g straw powder into 1g battery slag, and liquid-solid ratio 1:10, the cobalt leaching rate is over 98% after 1-2 h in 80-90 ℃. After three-stage leaching process, COD content can drop to about 1.3 g/L. In oxalate precipitating process, adjusting the pH of solution to 2, keeping n( )/n( ) of 1, cobalt precipitation rate is above 92% after 1h reaction under 50 ℃, and pH of the filtrate is 0.2, which can be circulated used as electrolytic leaching liquid.
Key words: spent Li-ion battery; electrolytic stripping; leaching; biomass acid leaching; CoC2O4
