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Hydroxypyridinone Derivatives: A Low-pH Alternative to Polyaminocarboxylates for TALSPEAK-like Separation of Trivalent Actinides from Lanthanides
Not Available
Characterization of a Ternary Neodymium-HEDTA-Citrate Complex in the Actinide Lanthanide Separation Process
Not Available
Glass-Bonded Monazite Waste Forms for Lanthanide and Actinide Immobilization: From Theoretical Design to Scale-Up Production and Characterization
The development of nuclear waste forms for both existing and future nuclear wastes is critical to ensuring global environmental safety. This study focuses on waste management from molten salt reactors, where fuel exists in a salt form and could be processed in real time for the removal of neutron poisons such as xenon isotopes (e.g., 135 Xe) and rare earth elements (REEs, e.g., 149 Sm). To ensure safe, stable, and long-term disposal in geological repositories, REEs must be incorporated into a durable waste form. Iron-phosphate glasses are a promising candidate due to their low melting points, high chemical durability, and their ability to incorporate high concentrations of REEs. In this study, we successfully prepared iron-phosphate glass waste forms with high Nd loadings (up to 37 mass %) in batch sizes ranging from small (23 g) to large (1600 g). The resulting materials contained up to 75 mass % NdPO 4 , contributing to their mechanical resilience and exceptional chemical durability. These findings highlight the potential of iron-phosphate glasses as high-efficiency, chemically durable waste forms and demonstrate the successful transition from theoretical design to scaled-up production.
Rare Earth Elements and Actinides: Progress in Computational Science Applications: Chapter 3 Title: Rare Earth Elements and Critical Materials: Uses and Availability
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Rare Earth Elements and Actinides: Progress in Computational Science Applications: Chapter Title: Preface
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Lanthanide surrogate development for actinide aerosol waste.
Abstract not provided.
Actinide 2-metallabiphenylenes that satisfy Hückel’s rule
Aromaticity and antiaromaticity, as defined by Hückel’s rule, are key ideas in organic chemistry, and are both exemplified in biphenylene—a molecule that consists of two benzene rings joined by a four-membered ring at its core. Biphenylene analogues in which one of the benzene rings has been replaced by a different (4n + 2) π-electron system have so far been associated only with organic compounds. In addition, efforts to prepare a zirconabiphenylene compound resulted in the isolation of a bis(alkyne) zirconocene complex instead. Here we report the synthesis and characterization of, to our knowledge, the first 2-metallabiphenylene compounds. Single-crystal X-ray diffraction studies reveal that these complexes have nearly planar, 11-membered metallatricycles with metrical parameters that compare well with those reported for biphenylene. Nuclear magnetic resonance spectroscopy, in addition to nucleus-independent chemical shift calculations, provides evidence that these complexes contain an antiaromatic cyclobutadiene ring and an aromatic benzene ring. Finally, spectroscopic evidence, Kohn–Sham molecular orbital compositions and natural bond orbital calculations suggest covalency and delocalization of the uranium f 2 electrons with the carbon-containing ligand.
Biological, biomolecular, and bio-inspired strategies for detection, extraction, and separations of lanthanides and actinides
This review surveys cellular and biomolecular methods to harvest f-block elements, emphasizing how recent characterization of lanthanide-utilizing bacteria is being translated into technologies to extract, separate, and sense these valuable elements.
Actinide tetra-N-heterocyclic carbene ‘sandwiches’
Highly-symmetrical, thorium and uranium octakis-carbene ‘sandwich’ complexes have been prepared by ‘sandwiching’ the An( iv ) cations between two anionic macrocyclic tetra-NHC ligands, one with sixteen atoms and the other with eighteen atoms.
Covalency in actinide( iv ) hexachlorides in relation to the chlorine K-edge X-ray absorption structure
Chlorine K-edge XANES of An( iv ) hexachlorides, calculated with multiconfiguration wavefunction theory, is interpreted in terms of similar metal–ligand covalency along the An = Th–Pu series.
Selective electrochemical capture and release of uranyl from aqueous alkali, lanthanide, and actinide mixtures using redox-switchable carboranes
Redox-switchable carboranes electrochemically capture and release UO 2 2+ selectively from mixed metal aqueous solutions, mimicking in part spent nuclear fuel.
Actinide arene-metalates: 2. A neutral uranium bis(anthracenide) sandwich complex and elucidation of its electronic structure
Reaction of [UI 2 (HMPA) 4 ]I with potassium anthracenide gives the unprecedented arenide-sandwich complex U(η 6 -C 14 H 10 )(η 4 -C 14 H 10 )(HMPA) 2 . CASSCF calculations indicate the U–C bonding to solely consist of π-interactions.
Engineering lanmodulin's selectivity for actinides over lanthanides by controlling solvent coordination and second-sphere interactions
Nature’s most potent protein for f-elements, lanmodulin, relies on subtle first-sphere/second-sphere interactions to bind metal ions. Dissecting lanmodulin’s binding mechanism yielded variants with enhanced actinide/lanthanide selectivity.
Actinide complexes with Wells–Dawson polyoxometalates (part 2): californium
We report the first example of a polyoxometalate (POM) compound containing californium. Using a Wells–Dawson POM ligand, K 17 Cf(P 2 W 17 O 61 ) 2 ·2H 2 O was synthesized and characterized. Californium is the heaviest element ever crystalized with a POM. Significant solubility differences among the POM's f-element complexes were observed, enabling selective precipitation with separation factors rivaling liquid–liquid extraction.
Stimuli-responsive photoswitch–actinide binding: a match made in MOFs
Photochromic radionuclide-based “claw machines” characterizedviaa combination of isothermal titration calorimetry and spectroscopic analysis unlock a pathway for on demand radionuclide capture and release.
Scoping Studies for a Lead-Lithium-Cooled, Minor-Actinide-Burning, Fission-Fusion Hybrid Reactor Design
Not provided.