Co-extraction of Mn2+, Co2+, and a part of Ni2+ from sulfuric acid solution containing Li+ using the new ionic liquids

In this study, five novel ionic liquids denoted by [RNH 3 ][Cyanex 272] where R = C 4 H 9 , C 6 H 13 , C 8 H 17 , C 10 H 21, and C 12 H 25 were synthesized in a one-step reaction of straight-chain primary amines and Cyanex 272. The singe-stage extraction performance of [RNH 3 ][Cyanex 272] for the separation of Mn 2+ , Co 2+ , Ni 2+ and Li + was investigated. Compared with the other [RNH 3 ][Cyanex 272], the [C 4 H 9 NH 3 ][Cyanex 272] has good selective extraction and separation of Mn 2+ , Co 2+ , and Ni 2+ due to the smaller different value between the radius of metal ion and the radius of [C 4 H 9 NH 3 ] + . Using a three-stage cross flow extraction, the extraction percentages of Mn 2+ , Co 2+ , Ni 2+ , and Li + were about 99.4, 99.1, 14.9 and 0.9 %. The [C 4 H 9 NH 3 ][Cyanex 272] is a good extraction agent for co-extraction of Mn 2+ , Co 2+ , and a part of Ni 2+ from Li + based on a three-stage cross flow extraction. Diluted sulfuric acid was used to strip the organic phase containing Mn 2+ , Co 2+ , and Ni 2+ , and the aqueous phase containing Mn 2+ , Co 2+ , and Ni 2+ can be used for the preparation of ternary precursor materials. The precipitation method can be used to prepare Ni(OH) 2 and Li 2 CO 3 from an aqueous phase containing Ni 2+ and Li + . The conceptual recycling flow-sheet for Mn 2+ , Co 2+ , Ni 2+ , and Li + from spent ternary lithium batteries was presented on basis of the new extraction agent. The slope method was also used to investigate the mechanism of the extractive reaction of Mn 2+ , Co 2+ , and Ni 2+ using the [C 4 H 9 NH 3 ][Cyanex 272].