30-2 Assessing Domestic Sources of Gallium: Evaluating Coal Ash as a Critical Mineral Resource

Session: Geological and Geochemical Investigations of Critical Minerals in New Mexico and Beyond, and Technological Advances in Extraction of Critical Minerals

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Abstract:

Gallium (Ga) has been listed as one of the critical minerals of importance to energy and national security in the United States. Currently, the U.S is 100% reliant on foreign countries for Ga supply. This poses a threat to national security and the economy because a 30% disruption in the market supply is estimated to cascade into a decline of more than 2% in the gross domestic product. It is projected that the demand for Ga in the U.S will double between 2025 and 2035 mainly driven by Ga’s application for energy. To reduce reliance on imports to meet the future Ga need, it is imperative to evaluate the potential of domestic feedstocks as sources of Ga. In this study, the potential of over 20 coal ash samples as domestic sources of Ga was investigated. The samples were collected from New Mexico, Arizona, Ohio, and Utah. The Ga concentrations were determined using Instrumental Neutron Activation Analysis. The mineralogy compositions were determined by X-ray Diffraction coupled with Rietveld refinement, and Scanning Electron Microscopy is used to study the morphology as well as identify the mineral phases that host the Ga in the coal ash samples.

SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525. This project is supported by DOE HERMES program and LDRD project #240658.

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