Abstract: Spent lithium-ion batteries (LIBs) blended with ammonium sulfate were roasted at elevated temperature. The effects of pH value of sulfuric acid leaching solution, roasting temperature and amount of ammonium sulfate on leaching rates of metal elements were investigated. Roasted residue was also leached with a mixed solution containing ammonia and ammonium sulfate. The results showed that all of lithium could be leached out. Due to the metallic copper in the roasting residue, the leaching rate of copper only reached 92.86% in sulfuric acid solution, but could be up to 97.60% in ammoniacal solution. Under the experimental conditions, the leaching rate was lower than 68% for cobalt because of undissolved Co3O4 in the roasted residue. The leaching rate of total cobalt was more than 99% when high concentration sulfuric acid with volume ratio of sulfuric acid to water at 1:2 was employed to treat the above leached residue.

Key words: spent lithium-ion battery, ammonium sulfate, roasting, leaching

摘要： 研究了废旧锂离子电池经(NH4)2SO4焙烧处理后有价金属的浸出行为. 考察了焙烧温度、(NH4)2SO4用量和浸出pH值对焙烧产物中金属元素浸出率的影响，比较了焙烧产物分别在稀硫酸溶液和含氨水与(NH4)2SO4的氨性溶液中的浸出效果. 结果表明，焙烧产物中的Li可被完全浸出，焙烧产物中Cu用氨性溶液浸出时浸出率达97.60%，在稀硫酸溶液中为92.86%，焙烧产物中部分钴以Co3O4的形态存在，浸出率低于68%，当用浓硫酸与水体积比为1:2的硫酸水溶液处理浸出渣时，Co的总浸出率可达99%以上.

关键词: 废旧锂离子电池, 硫酸铵, 焙烧, 浸出