skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Materials identification and surveillance project item evaluation: Items, impure plutonium oxide (ATL27960) and pure plutonium oxide (PEOR3258)

Technical Report ·
DOI:https://doi.org/10.2172/471405· OSTI ID:471405

In this report, Los Alamos scientists characterize properties relevant to storage of an impure plutonium oxide (74 mass % plutonium) in accordance with the Department of Energy (DOE) standard DOE-STD-3013-96. This oxide is of interest because it is the first impure plutonium oxide sample to be evaluated and it is similar to other materials that must be stored. Methods used to characterize the oxide at certain points during calcination include surface-area analyses, mass loss-on-ignition (LOI) measurements, elemental analysis, moisture-adsorption measurements, and quantitative supercritical-CO{sub 2} extraction of adsorbed water. Significant decreases in the LOI and surface area occurred as the oxide was calcined at progressively increasing temperatures. Studies indicate that supercritical-CO{sub 2} extraction is an effective method for removing adsorbed water from oxides. We extracted the water from powdered oxides (high-purity ZrO{sub 2}, pure PuO{sub 2}, and impure plutonium oxide) using CO{sub 2} at 3000 psi pressure and 75{degrees}C, and we quantitatively determined it by using gravimetric and dew-point procedures. The effectiveness of the extraction method is demonstrated by good agreement between the amounts of water extracted from pure zirconium and plutonium dioxides and the mass changes obtained from LOI analyses. However, the amount of moisture (0.025 mass %) extracted from the impure plutonium oxide after it had been calcined at 950{degrees}C and stored for a period of months is much less than the LOI value (0.97 mass %). These results imply that the impure plutonium oxide is free of adsorbed water after calcination at 950{degrees}C, even though the sample does not satisfy the LOI requirement of <0.50 mass % for storage.

Research Organization:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE, Washington, DC (United States)
DOE Contract Number:
W-7405-ENG-36
OSTI ID:
471405
Report Number(s):
LA-13246-MS; ON: DE97005917; TRN: 97:010328
Resource Relation:
Other Information: PBD: Mar 1997
Country of Publication:
United States
Language:
English