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Bridging Hydrometallurgy and Biochemistry: A Protein-Based Process for Recovery and Separation of Rare Earth Elements
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Antagonistic Role of Aqueous Complexation in the Solvent Extraction and Separation of Rare Earth Ions
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Ferrihydrite Transformation Impacted by Adsorption and Structural Incorporation of Rare Earth Elemen
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Ultra-Low Viscosity and High Magnetic Susceptibility Magnetic Ionic Liquids Featuring Functionalized Diglycolic Acid Ester Rare-Earth and Transition Metal Chelates
Magnetic ionic liquids (MILs) comprise a subcategory of ionic liquids (ILs) and contain a paramagnetic metal center allowing them to be readily manipulated by an external magnetic field. While MILs are popularly employed as solvents in catalysis, separations, and organic synthesis, most low viscosity combinations possess a hydrophilic character that limits their use in aqueous matrices. To date, no study has reported the synthesis and characterization of hydrophobic MILs with viscosities similar to those of hydrophilic MILs and organic solvents while simultaneously exhibiting enhanced magnetic and thermal properties. In this study, diglycolic acid esters are employed as ligands to chelate with paramagnetic metals to produce cations that are paired with metal chelates composed of hexafluoroacetylacetonate ligands to form MILs incorporating multiple metal centers in the cation and anion. Viscosity values below 31.6 cP were obtained for these solvents, the lowest ever reported for hydrophobic MILs. Solubilities in nonpolar solvents such as benzene were observed to be as high as 50% (w/v) MIL-to-solvent ratio while being insoluble in water at concentrations as low as 0.01% (w/v). Effective paramagnetic moment values for these solvents ranged from 5.33 to 15.56 Bohr magnetons (μB), with mixed metal MILs containing multiple lanthanides in the anion generally offering higher magnetic susceptibilities. MILs composed of ligands containing octyl substituents were found to possess thermal stabilities up to 190 °C. The synthetic strategies explored in this study exploit the highly tunable nature of the employed cation and anion pairs to design versatile ultra-low viscosity magnetoactive solvents that possess tremendous potential and applicability in liquid–liquid separation systems, catalysis, and microfluidics where the mechanical movement of the solvent can be easily facilitated using electromagnets.
Effect of the Growth Conditions on Organic Crystals with Rare Earth Ions and 1,10-Phenanthroline
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Using Diglycolamide Extractants in an Imidazolium-Based Ionic Liquid for Rare Earth Element Extraction and Recovery
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Advancing Rare-Earth (4 f ) and Actinide (5 f ) Separation through Machine Learning and Automated High-Throughput Experiments
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Rare Earth Elements and Actinides: Progress in Computational Science Applications: Chapter Title: Preface
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Precision Engineering of 2D Protein Layers as Chelating Biogenic Scaffolds for Selective Recovery of Rare-Earth Elements
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Dramatic Enhancement of Rare-Earth Metal–Organic Framework Stability Via Metal Cluster Fluorination
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Structural and Optical Response of Complex Mixed Gas Dynamics in Rare Earth Metal-Organic Frameworks.
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High-temperature quantum coherence of spinons in a rare-earth spin chain
Conventional wisdom dictates that quantum effects become unimportant at high temperatures. In magnets, when the thermal energy exceeds interactions between atomic magnetic moments, the moments are usually uncorrelated, and classical paramagnetic behavior is observed. This thermal decoherence of quantum spin behaviors is a major hindrance to quantum information applications of spin systems. Remarkably, our neutron scattering experiments on Yb chains in an insulating perovskite crystal defy these conventional expectations. We find a sharply defined spectrum of spinons, fractional quantum excitations of spin-1/2 chains, to persist to temperatures much higher than the scale of the interactions between Yb magnetic moments. The observed sharpness of the spinon continuum’s dispersive upper boundary indicates a spinon mean free path exceeding ≈ 35 inter-atomic spacings at temperatures more than an order of magnitude above the interaction energy scale. We thus discover an important and highly unique quantum behavior, which expands the realm of quantumness to high temperatures where entropy-governed classical behaviors were previously believed to dominate. Our results have profound implications for spin systems in quantum information applications operating at finite temperatures and motivate new developments in quantum metrology.