Spinning reactor recovers metals from spent Li

June 1, 2023 | By Gerald Ondrey

Recycling lithium batteries (LIBs) requires extensive use of hydrometallurgy, which requires multiple steps of extraction-stripping processes, each requiring separate reactors and different parameters. Although there have been attempts to devise a single-step, one-pot solution by partitioning the reactor using membranes, these efforts have failed in larger reactors, mostly due to membrane failures, especially under strong stirring.

To address this issue, an interdisciplinary research group, led by professor Bartosz A. Grzybowski at the Center of Soft and Living Matter within the Institute for Basic Science (IBS; Daejeon, South Korea; www.ibs.re.kr), reported a new method for recycling valuable metals such as lithium, nickel and cobalt, from spent lithium-ion batteries. Grzybowski's group has applied its spinning "concentric liquid reactors," to simplify the extraction-stripping process for LIB recycling. The study is described in a recent issue of Advanced Materials.

The horizontally rotating reactor (diagram), which was designed by co-author Olgierd Cybulski, can process complex metal mixtures in which aqueous feed, organic extractant and aqueous acceptor phases are all present in the same rotating vessel. Unlike the one-pot setups that use membranes, this reactor can be vigorously stirred and emulsified without the coalescence of aqueous layers. The arrangement of higher-pH "feed," organic extractant ("shuttle"), and lower-pH "acceptor" phases is maintained by placing all these liquids in a rotating vessel in a way that they form concentric layers stable enough to allow efficient interfacial mixing, but without coalescing the aqueous layers. "The technology is also forward-looking in the sense that, as we show, it is tunable to different "feed" metal compositions and of course, to metals other than those used in batteries," says Grzybowski.