THERMODYNAMICS AND PHASE RELATIONSHIPS FOR PLUTONIUM OXIDES

Technical Report · Fri Oct 31 00:00:00 EST 1958

DOI:https://doi.org/10.2172/4328220· OSTI ID:4328220

Holley, Jr, C E; Head, E L; Ellinger, F H; Bjorklund, C W

A compilation of available fundamental information concerning plutonium oxides. Methods of preparation, thermodynamic data, phase relationships, crystal structures, and some information on mixed oxide systems are considered. A bibliography is included. Methods of preparing PuO/sup 2/ by the peroxide and the oxalate processes and of lower oxides by thc reduction of PuO/sub 2/ are described and some chemical properties of plutonium oxides of interest in processing certain fuel elements are given. Thc fabrication of PuO/sub 2/ into discs is discussed. Measurements of heats of combustion a Pu, and Pu/sub 2/O/sub 3/ are described and the heats of formation of lower oxides and PuO/sub 2/ are given. Free energy data obtained by combining estimated entropies with the measured heats of formation are tabulated for the oxides. A tentative phase diagram for thc Pu-O system is presented which includes thc limiting solubility of oxygen in liquid plutonium, the ranges of stability of the three known oxide phases, hexagonal Pu/sub 2/O/sub 3/, a cubic oxide inaccurately designated as ''cubic Pu/sub 2/O/sub 3/'' and PuO/sub 2/, and some melting point data. (The crystal structures of the plutonium oxides have already been described in the literature and this will be reviewed. ) Crus tal structure data and methods of preparation for the PuO/sub 2/-UO/sub 2/, PuO/sub 2/-ThO/sub 2/, and PuO/sub 2/- CeO/sub 2/ solid solutions are described. (auth)

• Research Organization: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
• NSA Number: NSA-12-014721
• OSTI ID: 4328220
• Report Number(s): A/CONF.15/P/701
• Resource Relation: Other Information: Prepared for the Second U.N. International Conference on the Peaceful Uses of Atomic Energy, 1958. Orig. Receipt Date: 31-DEC-58
• Country of Publication: United States
• Language: English

Related Subjects

CHEMISTRY
BIBLIOGRAPHY
CERAMICS
CERIUM OXIDES
CHEMICAL REACTIONS
COMBUSTION
COMBUSTION HEAT
CRYSTALS
ENTROPY
FABRICATION
FORMATION HEAT
FREE ENERGY
FUEL ELEMENTS
HEATING
LATTICES
LIQUID METALS
MEASURED VALUES
MELTING POINTS
MIXING
OXALATES
PEROXIDES
PHASE DIAGRAMS
PLATES
PLUTONIUM
PLUTONIUM COMPOUNDS
PLUTONIUM OXIDES
PREPARATION
RADIOCHEMISTRY
REDUCTION
SOLID SOLUTIONS
SOLUBILITY
STABILITY
TABLES
THERMODYNAMICS
THORIUM OXIDES
URANIUM DIOXIDE