The lanthanide metals, with uses spanning from magnets and catalysts to cancer therapies, are unique resources. Ensuring their future accessibility depends on developing improved methods for isolating individual lanthanide elements from their groups, as traditional techniques are time-consuming, expensive, and generate waste.
“Our approach is flexible and can be tailored to select specific lanthanides for a faster route to separating adjacent elements,” said Oak Ridge National Laboratory’s Santa Jansone-Popova.
ORNL scientists combined two ligands, or metal-binding molecules, to target light and heavy lanthanides simultaneously for exceptionally efficient separation.
Solvent extraction leverages the separating feature of oil-water mixtures and typically employs ligands that guide targeted materials from water to oil. The new strategy pairs an oil-loving ligand that seeks heavier lanthanides with a water-loving counterpart that targets lighter elements. The tug-of-war match-up pulls apart lanthanides that are especially difficult to divide.
“Fundamental discoveries such as this one can advance economical and environmentally responsible separations strategies,” Jansone-Popova said.
Reference: “Size Selective Ligand Tug of War Strategy to Separate Rare Earth Elements” by Katherine R. Johnson, Darren M. Driscoll, Joshua T. Damron, Alexander S. Ivanov and Santa Jansone-Popova, 25 January 2023, JACS Au.