High Pressure DME-Driven Fractional Crystallizations

Kline, Caleb Matthew [Idaho National Laboratory]

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DOE OSTI · 3364335

High Pressure DME-Driven Fractional Crystallizations

Kline, Caleb Matthew [Idaho National Laboratory]

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Abstract

Rare Earth Elements (REEs), include the 15 lanthanides plus yttrium and scandium and are crucial for various technologies and applications. Their low concentrations in the earth's crust require alternative sources. This study explores antisolvent fractional crystallization (FC) using dimethyl ether (DME) under high pressures to extract REEs from secondary sources such as mining waste, coal byproducts, and e-waste. DME's properties, including its solubility in water, small molecular size, and high vapor pressure, make it an effective antisolvent that can be easily recovered and reused. The method involves pressurizing DME to 1000-2000 psi in a reaction chamber with the test solution, followed by sample collection and analysis using ICP-MS and ICP-OES. This approach aims to address the limitations of current extraction methods, such as high energy consumption, chemical usage, and waste production, offering a potentially more efficient and sustainable solution for REE extraction.

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37 - INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY Chemical Seperations Critical Materials Fractional Crystallization REE's

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Kline, Caleb Matthew [Idaho National Laboratory]. 2025-08-13. High Pressure DME-Driven Fractional Crystallizations. https://www.osti.gov/biblio/3364335

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