(610g) A Molecular-Scale Study of Monazite Beneficiation through Computational and Spectroscopic Techniques

Sourcing rare-earth elements (REEs) is an active area of research due to their wide array of applications, ranging from energy to defense sectors.¹ An important step in the processing of REEs is mineral beneficiation, which is a process that separates valuable REE-containing minerals from undesired gangue materials, partly through a method known as froth flotation. During the flotation process, collector agents are introduced to a slurry of ground minerals which selectively bind to the REE-containing mineral and allows for collection. A promising REE-containing mineral for this application is monazite, which can contain various REEs, including Ce, La, and Nd. However, there is limited information on both the crystal morphology and the basic surface chemistries of monazite. Therefore, we have performed density functional theory (DFT) calculations to predict La-monazite crystal morphology via Wulff construction by computing surface energies for several low-index facets in the absence and presence of water. We also evaluate the performance of collector ligands for the predominant facets of monazite using computational and spectroscopic techniques. This work grants fundamental insight into the beneficiation process of monazite and helps guide the design of future collector agents for froth flotation applications.

References

[1] R. Eggert, C. Wadia, C. Anderson, D. Bauer, F. Fields, L. Meinert and P. Taylor, “Rare Earths: Market Disruption, Innovation, and Global Supply Chains”, Ann. Rev. Environ. Resour., 2016, 41, 199-222.

Acknowledgement

This research was supported by the Critical Materials Institute, an Energy Innovation Hub funded by the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Advanced Manufacturing Office.