废旧三元电池正极活性材料盐酸浸出液中钴锰共萃取分离镍锂

Separation of Nickel and Lithium by Co-extraction of Cobalt and Manganese in Hydrochloric Acid Leaching Solution of a Cathode Material in Spent Lithium-ion Batteries

废旧三元电池正极活性材料盐酸浸出得到含金属钴、锰、镍、锂的浸液,比较选择了新型萃取体系Aliquat336+TBP/煤油共萃取钴锰并分离镍锂,提出了浸液中回收有价金属的新方法。研究了萃取剂种类、修饰剂、萃取剂浓度和相比等因素对钴锰共萃取分离镍和锂的影响。研究表明,当浸出液中氯离子浓度高于6.5M时,Aliquat336+TBP在煤油稀释剂中能够有效萃取钴锰分离镍锂,其它胺类萃取剂如Alamine 304、Alamine 308和Alamine336萃取效果明显低于Aliquat 336。优化条件下Aliquat 336+TBP体系对Co/Mn、Co/Ni和Co/Li分离系数分别为7、1 061、3 183;Mn/Ni和Mn/Li分离系数分别为156和468,表明钴锰能实现高效共萃,并与镍锂高效分离。TBP在体系中主要作为相修饰剂,但对钴锰的萃取起到了协同萃取的效果。采用Aliquat 336+TBP萃取体系共萃取钴锰,设计了废旧三元电池正极活性材料盐酸浸出液中回收钴镍锰锂的新方法。

The leaching solution containing metal ions cobalt, manganese, nickel and lithium is obtained by hydrochloric acid leaching of spent NCM LiBs cathode materials. A new extraction system, mixed A1- iquat 336 ＋ TBP with kerosene, is selected for co-extraction of cobalt and manganese to separation from nickel and lithium in the leaching solution. A new method for recovering valuable metals in the immersion solution is proposed. The effects of extractant type, modifier, extractant concentration and comparison on cobalt and manganese co-extraction are studied. The results show that when the concentration of chloride ion in the leaching solution is higher than 6. 5 M, Aliquat 336 ＋ TBP can effectively extract cobalt and manganese, and the extraction efficiencies of amine extractants, such as Alamine 304, Alamine 308 and Alamine 336, are obviously lower than that of Aliquat 336. The separation efficiencies of Co/Mn, Co/Ni and Co/Li in Aliquat 336 ＋ TBP system are 7, 1061, 3183, respectively. The separation efficiencies of Mn/Ni and Mn/Li are 156 and 468, indicating that cobalt and manganese can achieve efficient co-extrac- tion and high efficient separation with nickel and lithium. TBP is mainly used as phase modifier in the system, but it has synergistic extraction effect on Co-Mn co-extraction. A new method of recovering co- balt, nickel, manganese and lithium from hydrochloric acid leaching solution of spent NCM LiBs cathode materials is designed by co-extraction of cobalt and manganese by Aliquat 336 ＋ TBP extraction system.