(383h) Ambient Electrochemical Flow for Separating Critical Materials from Industrial Scrap and E-Waste

The increasing demand for clean energy and the subsequent electrification of transport has resulted in a significant increase in critical material production and recycling demand. This has led to a glaring supply bottleneck as the production and refinement of necessary rare earth materials is supplied from a mere few sources. In this study a scalable bench-top setup of a closed-loop electrochemical flow cell operating at room temperature is used to demonstrate direct alloy-to-metal recovery of cobalt metal, along with its separation from samarium within SmCo magnets. This design was implemented using various SmCo sources such as magnets and pure Sm₂Co₇ powder. An optimized electrolyte based on industrial solvent was also developed. A novel closed-loop flow cell design provides modularity in separations techniques by allowing the combination of multiple recycling streams as well as increasing the throughput of electrochemical deposition via reduced mass transport limitations. This resulted in high-purity (>95%) recovered metallic cobalt with high Faradaic efficiencies (>85%) and low energy cost (<1 V of required potential). Such a system can vastly increase critical materials supply by both recycling post-consumer materials and proposing a more energy efficient path for future critical materials recycling.