Segmented concentric-liquid reactor, a) cross-section of the reactor loaded with liquids, b) front view (along the axis of rotation) photograph of the actual rotor in the non-stirring mode, and c) side view of the rotor with the same content but in the stirring mode.
Newswise —
Lithium-ion batteries are used as an alternative to carbon-based energy, but they create more waste. The batteries slowly lose their ability to hold a charge over time, and their parts can also break down, causing environmental and safety problems if they are not disposed of properly.
To recycle lithium batteries, a process called hydrometallurgy is used. This involves using liquids to extract valuable metals from the used battery. First, the battery is taken apart and the metals are extracted using a solvent. The extracted metal is then recovered and the solvent is reused. The current process for recycling lithium batteries involves multiple steps of extraction and stripping, which requires separate reactors and different conditions. This makes the recycling process complex and expensive, which is why the recycling rate for lithium batteries is currently very low.
Many attempts have been made to develop a single-step, one-pot solution for recycling lithium batteries by using membranes to partition the reactor. Unfortunately, these attempts have been unsuccessful in larger reactors, mainly due to membrane failures that occur, especially under strong stirring.
Professor Bartosz A. Grzybowski and his interdisciplinary research team at the Center of Soft and Living Matter within the Institute for Basic Science (IBS) in South Korea have developed a new method to recycle valuable metals such as lithium, nickel, and cobalt from used lithium-ion batteries. The team used their spinning 'concentric liquid reactors', which have been proven to be effective in carrying out multi-step reactions in a single chamber, to simplify the extraction-stripping process for recycling lithium batteries.
The researchers developed a new method to recycle valuable metals such as lithium, nickel, and cobalt from used lithium-ion batteries. They used a horizontally rotating reactor, designed by co-author Dr. Olgierd Cybulski, which can process complex metal mixtures in a single vessel. Unlike other reactors that use membranes, this reactor can be vigorously stirred without mixing the different liquids. The arrangement of different liquids is maintained by placing them in a rotating vessel, which forms concentric layers that allow efficient mixing without coalescing the different layers.
Impressively, this process “can perform the separation of metals in a matter of minutes, using a low concentration of extracting agents and with high selectivity”, according to co-author Dr. Cristóbal QUINTANA.
This study found that using the concentric liquid reactor can extract valuable metals from used batteries more efficiently and with less extractant than current methods. The reactor can also work under a wider range of conditions.
The concentric liquid reactors have several advantages over traditional hydrometallurgical methods in terms of lower concentrations of extractants, access to unexplored process parameters, favorable power-to-operate vs. reactor-size scaling, and potential applicability to other valuable metals. The technology is also flexible and can be adapted to different metal compositions beyond those found in batteries.
RSS