Abstract
This research presents a sustainable approach for the simultaneous recycling of spent lithium-ion batteries (LIBs) and nickel-metal hydride batteries (NiMHs). First, dissolution of LIBs and NiMHs were found to be mutually co-promoted, resulting in above 98% extraction of Li, Co, Ni, and rare-earth elements (REEs) without the need for any oxidant or reductant additions. After leaching, >97% of REEs were recovered as a REEs-alkali double sulfate precipitate with the addition of NaOH and Na2SO4 precipitants. This REEs-free solution was then further processed to separate and recover the battery metals present: Mn, Co, Ni, and Li. The resultant residual solution (rich in NaOH and Na2SO4) was redirected to the REEs precipitation step, decreasing both the need of precipitants (e.g., Na2SO4) as well as the costs related to the treatment of the high-Na waste solution. Moreover, the Li remaining in the waste solution can be circulated back into the main process, resulting in an exceptionally high Li recovery of >93% in the form of high-purity Li3PO4 (99.95%). This is a marked improvement over the previously reported Li recovery levels of 60-80%. Overall, this newly developed process has considerable environmental and economic advantages for the recovery of valuable metals from mixed LIBs and NiMHs wastes.
Original language | English |
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Pages (from-to) | 16103-16111 |
Number of pages | 9 |
Journal | ACS Sustainable Chemistry and Engineering |
Volume | 7 |
Issue number | 19 |
DOIs | |
Publication status | Published - 7 Oct 2019 |
MoE publication type | A1 Journal article-refereed |
Funding
This paper has been financially supported by the Strategic Research Council of the Academy of Finland (Closeloop project, Grant Number 303454). The authors also acknowledge the collaboration with Business Finland supported projects (CMEco and BATCircle, Grant Numbers 7405/31/2016 and 4853/31/2018), and the Academy of Finland’s RawMatTERS Finland Infrastructure (RAMI) based at Aalto University. The authors also acknowledge the financial support from the National Nature Science Foundation of China (No. 51804141) as well as the Science and Technology Project of the Education Department of Jiangxi Province (GJJ170533). Special thanks also go to AkkuSer Ltd. for providing the spent battery waste used in this study.
Keywords
- Lithium
- Metals circular economy
- Rare-earth elements
- Sustainable recycling
- Synergistic leaching