REDUCTION OF URANIUM HEXAFLUORIDE RETENTION ON BEDS OF MAGNESIUM FLUORIDE USED FOR REMOVAL OF TECHNETIUM HEXAFLUORIDE

Technical Report · Fri Jan 31 00:00:00 EST 1964

DOI:https://doi.org/10.2172/4119871· OSTI ID:4119871

Katz, S.

The excessive loss of uranium incurred when discarding magnesium fluoride, (the adsorber used to selectively remove technetium hexafluoride from uranium hexafluoride streams) is a problem common to all volatility processes for recovering enriched uranium fuels. As a result of the work described, two schemes for the release of the uranium hexafluoride from the magnesium fluoride and its separation from the technetium hexafluoride are proposed. One scheme depends on preferential thermal desorption of the uranium hexafluoride at 350 deg C and the other on selective adsorption of the uranium hexafluoride on sodium fluoride pellets following the codesorption of the two hexafluorides with fluorine at 500 deg C from the magnesium fluoride pellets. These proposals are aimed at reducing the amount of retained uranium to less than 1 g per 1000 g of discardable magnesium fluoride. In the work reported, the deposition of uranium on magnesium fluoride as a function of heating, fluorination, and hydrogen fluoride pretreatment of the magnesium fluoride pellets prior to exposure to uranium hexafluoride was characterized in a series of gasometric studies. The dependence of the quantity of uranium hexafluoride adsorbed on pressure and temperature was also determined. The data show that physical adsorption is the mechanism for the deposition of most of the uranium hexafluoride on well- stabilized magnesium fluoride pellets. More than 90% of the adsorbate can be removed by heating to 350 deg C. Chemisorption (formation of a double salt) is probably not involved because of the small (<0.05) mole ratio of UF/sub 6//MgF/ sub 2/ observed. (auth)

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• DOE Contract Number: W-7405-ENG-26
• NSA Number: NSA-18-012038
• OSTI ID: 4119871
• Report Number(s): ORNL-3544
• Resource Relation: Other Information: Orig. Receipt Date: 31-DEC-64
• Country of Publication: United States
• Language: English

Related Subjects

CHEMISTRY
ADSORPTION
CHEMICAL REACTIONS
ENRICHMENT
FLUORINATION
FLUORINE
FUEL ELEMENTS
HEATING
HYDROFLUORIC ACID
LOSSES
MAGNESIUM FLUORIDES
PELLETS
PRESSURE
QUALITATIVE ANALYSIS
QUANTITATIVE ANALYSIS
REDUCTION
SEPARATION PROCESSES
SODIUM FLUORIDES
STABILITY
TECHNETIUM FLUORIDES
TEMPERATURE
URANIUM
URANIUM HEXAFLUORIDE
USES
VARIATIONS
VOLATILITY