Rare earth elements (REEs) are a group of 17 heavy metals found throughout modern society, from medical equipment, to cellphones, to clean energy technologies like electric vehicles. Despite the name, REEs are easy to find but difficult to extract and purify. Mines are the traditional source for REEs, yet have long-lasting and detrimental effects on the environment. Therefore, there is an urgent need to develop new and environmentally friendly methods to meet the demand for REEs. REE extraction from wastewater streams presents a promising solution that supports a circular economy by reusing toxic metals that would otherwise be released to the environment.

This project investigates computationally both light REEs: europium (Eu), lanthanum (La) and neodymium (Nd), and heavy REEs: ytterbium (Yb), dysprosium (Dy) and samarium (Sm) to capture trends across the rare earth element series. Explicit water solvation is employed to accurately describe hydration structure, ligand competition, and metal-ligand bonding under realistic aqueous conditions. We quantify binding affinities, coordination environments, and electronic structure descriptors to examine how chelation strength and solvation effects influence the thermodynamic and kinetic feasibility of electrochemical REE recovery. Insights from this work will provide fundamental design principles for electrochemical separation strategies to selectively recover REEs from complex wastewater streams.