REPROCESSING OF URANIUM CARBIDE BY A NITRIDE-CARBIDE CYCLE. I. KINETICS OF NITRIDE FORMATION

Technical Report · Thu Oct 31 04:00:00 EST 1963

OSTI ID:4176053

Hanson, L A

The reaction of uranium carbide with nitrogen was investigated in relation to the effects of: UC age (time of UC exposure to air saturated with water vapor at room temperature) in the range from 0 to 120 days; initial UC particle size from 4 mesh to less than 400 mesh; UC composition from 3.59 to 5.55 wt% carbon; nitrogen pressure from 10 to 600 mm Hg sbsolute; and reaction temperature from 550 to 1050 deg C. The reaction changes the UC to a powder consisting of a mixture of carbon and uranium nitrides; the principal nitride phase was identified as U/sub 2/N/sub 3/. The reaction rate of aged UC is higher by a factor of 28 over freshly melted UC. The reaction rate varies with UC particle size, having a maximum rate for --400 mesh powder and a minimum for the 100 to 200 mesh size fraction. The reaction rate varies with uranium carbide composition and is a minimum for slightly hypostoichiometric UC. The reaction rate varies as the 3/4 power of the nitrogen pressure. The reaction rate is postulated as being controlled by the formation of the U/sub 2/N/sub 3/ phase below 650 deg C; whereas, above 650 deg C, the observed reaction rate is a combination of a primary process, U/sub 2/N/sub 3/ formation, and a secondary inhibiting effect probably caused by the decomposition of the U/sub 2/N/sub 3/ phase. Activation energies of 31.8 plus or minus 1.3 kcal/mole for the primary reaction andd 37.4 plus or minus 2.2 kcal/mole for the secondary reaction were determined. Oxidation of the nitride in air at room temperature was noted. (auth)

• Research Organization: Atomics International. Div. of North American Aviation, Inc., Canoga Park, Calif.
• DOE Contract Number: AT(11-1)-GEN-8
• NSA Number: NSA-18-000204
• OSTI ID: 4176053
• Report Number(s): NAA-SR-8388
• Country of Publication: United States
• Language: English

Related Subjects

ACETATES
ACRYLIC ACID
AIR
BUTYL RADICALS
CARBON
CHEMICAL REACTIONS
CHEMISTRY
CYANIDES
GRAIN SIZE
HIGH TEMPERATURE
IRRADIATION
MIXING
NITRILES
NITROGEN
NUMERICALS
ORGANIC FLUORINE COMPOUNDS
OXIDATION
POLYMERIZATION
POWDERS
PROPYL RADICALS
RADIATION CHEMISTRY
RADIATION DOSES
REACTION KINETICS
REPROCESSING
STYRENE
URANIUM CARBIDES
URANIUM NITRIDES
VAPORS
VINYL RADICALS
WATER