Geo-inspired Separation of Rare-earth Elements

Rare earth elements (REEs) are essential to the economic growth and national security of the United States, and the supply chain of these critical minerals becomes increasingly vulnerable to disruptions. To effectively exploit secondary sources of REEs, we must learn about the localized environment of REEs in these sources and enable enhanced recovery and separation approaches optimized across a variety of REEs and sources.

The goal of this project is to understand spatio-chemical environment, speciation, and selective adsorption of rare earth elements (REE) in regolith-hosted ionic adsorption clays and electrostatic interactions with their immediate environment. Our vision is to provide the necessary fundamental understanding of REEs in natural and synthetic layered clays, and the effects of hydration and solvents on REE-clay interactions that will underpin future developments in both RE separations and recovery from secondary sources. The understanding of key structural components and REE behaviors in natural clays, including effects of hydration and of solvents, will directly inform the growing effort to explore new approaches to REE recovery and separation and will enable more efficient REE separation from complex mixtures and diverse low-grade REE feedstocks.

This effort brings together cutting- edge theory, synthesis, and characterization capabilities afforded by Liquid Phase Scanning Transmission Electron Microscopy (LP S/TEM), Atom Probe Tomography (APT), synchrotron-based spectroscopy, and high performance computing resources (NERSC award) to gain a fundamental understanding of spatio- chemical environment, electrostatic interactions, speciation, and retention of REEs in ionic adsorption clays. The research team includes researchers from Ames National Laboratory, Pacific Northwest National Laboratory, and University of Alabama.

This research was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division, Separation Science program. Ames National Laboratory is operated for the U.S. Department of Energy by Iowa State University under Contract No. DEAC02-07CH11358.

Principal Investigator: Tanya Prozorov

Co-PIs (Ames Laboratory): Jared Anderson, James Evans, Theresa Windus

Co-PI (Pacific Northwest National Laboratory): Shawn Kathmann