Probable leaching mechanisms for UO/sub 2/ and spent fuel

Conference · Tue Jan 01 04:00:00 EST 1980

OSTI ID:6663537

Wang, R.; Katayama, Y. B.

The oxidation and dissolution mechanisms for UO/sub 2/ and spent fuel will be quite similar based on this preliminary work with electrochemical leaching of UO/sub 2/ and spent fuel. In solutions containing oxygen or other oxidizing species, the UO/sub 2/ surface will be rapidly oxidized and dissolved following the transformation of uranium from U(IV) to U(VI). The hydrolysis of dissolved uranyl ions forms solid UO/sub 3/ hydrates or related complex compounds deposited onto the UO/sub 2/ surface, or other surfaces, as thin or thick coatings. Depending on the pH, temperature, and time, the various kinds of porosity and the mechanical properties of the hydrate coatings will control the dissolution rate. The effects of radiation, in terms of generation of H/sub 2/O/sub 2/, will enhance the dissolution kinetics. Electrochemical methods may be useful for determining the surface conditions, dissolution rate, and accelerated dissolution behavior for NO/sub 2/ and spent fuel. Electrochemial methods can rapidly generate much information in terms of dissolution rate and surface film properties - such as thickness, porosity, and oxidation state - in-situ during the leaching process.

• Research Organization: Battelle Pacific Northwest Labs., Richland, WA (USA)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6663537
• Report Number(s): PNL-SA-8744; CONF-801124-42
• Country of Publication: United States
• Language: English

Related Subjects

052002* -- Nuclear Fuels-- Waste Disposal & Storage
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
36 MATERIALS SCIENCE
360205 -- Ceramics
Cermets
& Refractories-- Corrosion & Erosion
ACTINIDE COMPOUNDS
AUTOCLAVES
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COHERENT SCATTERING
DIFFRACTION
DISSOLUTION
ELECTROLYSIS
ENERGY SOURCES
FUELS
HIGH TEMPERATURE
HYDROGEN COMPOUNDS
HYDROGEN PEROXIDE
KINETICS
LEACHING
LYSIS
MATERIALS
MEDIUM TEMPERATURE
NUCLEAR FUELS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PEROXIDES
PH VALUE
RADIATION EFFECTS
REACTION KINETICS
REACTOR MATERIALS
SCATTERING
SEPARATION PROCESSES
SPENT FUELS
SURFACES
URANIUM COMPOUNDS
URANIUM DIOXIDE
URANIUM OXIDES
X-RAY DIFFRACTION