(437a) Molecular Design of Redox-Mediated Electrochemical Separations for Critical Element Recovery

Separation processes are critical to mining and mineral processing, through the purification and concentration of valuable elements. Maximizing metal recovery while reducing water and chemical usage are central to innovating mining, for applications ranging from primary metal extraction, value recovery from tailings or acid drainage, to the recycling of valuable resources from unconventional feedstocks.

Electrochemical approaches are a promising pathway towards sustainable mining, through renewable-electron driven separations. Control of the redox electron-transfer at electrochemical interfaces allows for reversible binding and release of target molecules. First, we present the development of redox-electrochemical technologies for the recovery and purification of critical metals, including platinum group metals (PGMs) and rare-earth elements (REEs). We also highlight new electrochemical approaches for battery and electronic waste recycling, targeting both noble metals as well as critical elements such as lithium, cobalt, and nickel. We demonstrate for the first time how redox-platforms can be translated to continuous and scalable metal extraction operations in an electrochemical liquid-liquid extraction (e-LLE) system. On the long-term, we envision electrochemical processes as an integral part of future sustainable mining framework, by coupling with upstream ore extraction, beneficiation, and sustainable hydrometallurgical techniques.