CMI Winter Meeting 2025 Presentation

Tolbert, Chloe Leighanna [Idaho National Laboratory] (ORCID:0000000315804960)

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DOE OSTI · 3017663

CMI Winter Meeting 2025 Presentation

Tolbert, Chloe Leighanna [Idaho National Laboratory] (ORCID:0000000315804960)

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Abstract

Lanthanides are important to many technologies including magnets used in high efficiency traction motors. While common in the environment and industrial waste streams, lanthanides are often present at very low concentrations. This work demonstrates synergistic lanthanide recovery from an aqueous magnet leachate to single ppm concentrations using Na2SO4 addition and subsequent DME-FC treatment. It was found that combining DME-FC with low concentrations of Na2SO4 (~0.1 M) results in synergistic isolation of lanthanides while making use of Na2SO4, an excessive byproduct of hydrometallurgical metal production. Combined Na2SO4 + DME reduced lanthanide metal ion's (Pr, Nd, Sm, Gd, Dy, and Ho) solubilities by 1,000 - 25,000x with final concentrations ranging from 2 ppm to 200 ppm. This can be compared to 0.1 M Na2SO4 alone providing a 10 - 200x reduction and DME providing a 100 - 1,500x reduction in lanthanide solubilities. Final solution concentrations of lanthanides were 99.8% lower than what could not be achieved with either individual process. The results also reveal different periodic trends in the solubility reduction for DME and Na2SO4.

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37 - INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY critical materials dimethyl ether fractional crystallization lanthanide separation rare earth elements

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Tolbert, Chloe Leighanna [Idaho National Laboratory] (ORCID:0000000315804960). 2025-02-12. CMI Winter Meeting 2025 Presentation. https://www.osti.gov/biblio/3017663

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