Efficient recycling of spent lithium-ion batteries, LIBs, is essential for making their numerous applications sustainable. Hydrometallurgy-based separation methods are an indispensable part of the recycling process but remain limited by the extraction efficiency and selectivity, and typically require numerous binary liquid-liquid extraction steps in which the capacity of the extracting organic phase or partition coefficient of extracted metals become an overall bottleneck.
In this paper, we describe rotating reactors in which aqueous feed, organic extractant, and aqueous acceptor phases are all present in the same, rotating vessel and can be vigorously stirred and emulsified without the coalescence of aqueous layers.
—Quintana et al.
The reactors contain a higher pH aqueous feed and a lower pH aqueous acceptor phase that are kept separate by an inorganic solvent. The extractant molecules “shuttle” between the feed/extractant and the extractant/acceptor interfaces multiple times, with each such molecule ultimately transferring ∼10 metal ions.
The researchers said that this shuttling allows for using extractant concentrations much lower than in previous designs even for extremely concentrated feeds and, simultaneously, ensures unprecedented speed and selectivity of the one-pot processes.
Resources
Quintana, C., Cybulski, O., Mikulak-Klucznik, B., Klucznik, T. and Grzybowski, B.A. (2023), “One-Pot, Three-Phase Recycling of Metals from Li-Ion Batteries in Rotating, Concentric-Liquid Reactors.” Adv. Mater.. Accepted Author Manuscript 2211946doi: 10.1002/adma.202211946
