Research in actinide chemistry

Technical Report · Sun Jan 01 04:00:00 EST 1989

OSTI ID:5608993

Research continued to be focused broadly on the chemistry of the actinide cations in solution. While the direct concern is the actinide elements, their radioactivity limits the techniques which can be applied to their study. A major area of interest continues to be the thermodynamics of interaction of the f-elements with a broad spectrum of inorganic and organic ligands. Solvent extraction (for tracer levels), potentiometric and calorimetric titration and absorption spectrometry have been used to obtain stability constants and the associated enthalpy and entropy changes for complexation. A number of studies were performed to provide a better data base and a better understanding of the more significant species determining the behavior of actinides in natural waters (e.g., hydrolysis and silicate interaction). A second major area has been kinetics. NpO{sub 2}{sup 2+} reduction by hydroxy and carboxylic acids was studied to obtain an understanding of how such functional groups in humic substances may influence actinyl redox. The kinetics of dissociation of UO{sub 2}{sup 2+} and Ln{sup 3+} (La{sup 3+} = lanthanide element cations) from synthetic polyelectrolytes and humics provided significantly increased understanding of actinide complexation by these macromolecules. A third area of activity used laser induced fluorescence to study the hydration state of Eu(III) in a number of systems. Finally, several other studies, not in these major areas, were conducted. These included investigation of NpO{sub 2}{sup +} cation-cation complexes, the extraction of Am(III) by MX (M = Li, Na, NH{sub 4}{sup +}, K{sup +}; X = ClO{sub 4}{sup {minus}}, Cl{sup {minus}}, NO{sub 3}{sup {minus}}, BrO{sub 3}{sup {minus}}) over a concentration range from 0.01 M to saturated and the thermodynamics of synergistic extraction of actinides by crown ethers and {beta}-diketonates. 23 refs., 1 fig.

• Research Organization: Florida State Univ., Tallahassee, FL (USA). Dept. of Chemistry
• Sponsoring Organization: DOE/ER
• DOE Contract Number: FG05-87ER40329
• OSTI ID: 5608993
• Report Number(s): DOE/ER/40329-3; ON: DE90000019
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400201 -- Chemical & Physicochemical Properties
400702* -- Radiochemistry & Nuclear Chemistry-- Properties of Radioactive Materials
ACTINIDE COMPLEXES
ACTINIDE COMPOUNDS
ACTINIDES
AMERICIUM COMPOUNDS
AMERICIUM FLUORIDES
AROMATICS
CARBON COMPOUNDS
CARBONATES
CATIONS
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHEMICAL STATE
COMPLEXES
DISPERSIONS
DISSOCIATION
DOCUMENT TYPES
ELEMENTS
EUROPIUM COMPOUNDS
EUROPIUM FLUORIDES
EXTRACTION
FLUORESCENCE
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HUMIC ACIDS
HYDROXY COMPOUNDS
IONS
KINETICS
LUMINESCENCE
METALS
MIXTURES
NEPTUNIUM COMPOUNDS
NEPTUNIUM OXIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHENOLS
PHOSPHATES
PHOSPHORUS COMPOUNDS
PROGRESS REPORT
RARE EARTH COMPOUNDS
RARE EARTHS
REACTION KINETICS
REDUCTION
SAMARIUM
SEPARATION PROCESSES
SILICATES
SILICON COMPOUNDS
SOLUTIONS
SOLVENT EXTRACTION
STABILITY
TRANSPLUTONIUM COMPOUNDS
TRANSURANIUM COMPOUNDS
URANIUM COMPOUNDS
URANIUM OXIDES