(五邑大學(xué) 化學(xué)與環(huán)境工程系， 江門 529020)
摘 要: 采用堿溶解→酸浸出→P204萃取凈化→P507萃取分離鈷、 鋰→反萃回收硫酸鈷和萃余液沉積回收碳酸鋰的工藝流程， 從廢舊鋰離子二次電池中回收鈷和鋰。實驗結(jié)果表明： 堿溶解可預(yù)先除去約90%的鋁， H2SO4+H2O2體系浸出鈷的回收率達到99%以上； P204萃取凈化后， 雜質(zhì)含量為Al 3.5mg/L、 Fe 0.5mg/L、 Zn0.6mg/L、Mn2.3mg/L、 Ca ＜0.1mg/L； 用P507 萃取分離鈷和鋰， 在pH為5.5時， 分離因子βCo/Li可高達1×105；95℃以上用飽和碳酸鈉沉積碳酸鋰， 所得碳酸鋰可達零級產(chǎn)品要求，一次沉鋰率為76.5%。
關(guān)鍵字: 固體廢物; 鋰離子二次電池; 回收; 硫酸鈷; 碳酸鋰
spent lithium-ion secondary batteries
（Department of Chemical & Environmental Engineering,
Wuyi University, Jiangmen 529020, China）
Abstract: The separation and recovery of metal values such as cobalt and lithium from spent lithium-ion batteries were investigated. The results show that more than 90% of aluminum is removed by alkali dissolution, leaching efficiency of more than 99% of cobalt and lithium can be achieved when H2SO4+H2O2 solution is used at 80℃. The impurties in the leach liquor is extracted selectively and nearly completely with D2EHPA. The concentrations of impurties are decreased as low as Al 3.5mg/L, Fe 0.5mg/L, Zn 0.6mg/L, Mn 2.3mg/L and Ca ＜0.1mg/L, respectively. The cobalt in the liquor is extracted selectively with PC-88A in kerosene at equilibrum pH≈5.5, and the Co/Li separation factor is as high as 1×105. It is followed by stripping with H2SO4 solution. The raffinate is concentrated and the lithium remaining in the aqueous is readily recovered as lithium carbonate precipitate by the addition of a saturated sodium carbonate solution at 95℃.
Key words: solid waste; lithium-ion secondary battery; recovery; cobalt sulfate; lithium carbonate
