On the Use of Thermal NF3 as the Fluorination and Oxidation Agent in Treatment of Used Nuclear Fuels

Journal Article · Tue May 01 00:00:00 EDT 2012 · Journal of Nuclear Materials, 424(1-3):224-236

DOI:https://doi.org/10.1016/j.jnucmat.2012.03.004· OSTI ID:1038367

Scheele, Randall D; McNamara, Bruce K; Casella, Andrew M; Kozelisky, Anne E

This paper presents results of our investigation on the use of nitrogen trifluoride as the fluorination or fluorination/oxidation agent for use in a process for separating valuable constituents from used nuclear fuels by employing the volatility of many transition metal and actinide fluorides. Nitrogen trifluoride is less chemically and reactively hazardous than the hazardous and aggressive fluorinating agents used to prepare uranium hexafluoride and considered for fluoride volatility based nuclear fuels reprocessing. In addition, nitrogen trifluoride’s less aggressive character may be used to separate the volatile fluorides from used fuel and from themselves based on the fluorination reaction’s temperature sensitivity (thermal tunability) rather than relying on differences in sublimation/boiling temperature and sorbents. Our thermodynamic calculations found that nitrogen trifluoride has the potential to produce volatile fission product and actinide fluorides from candidate oxides and metals. Our simultaneous thermogravimetric and differential thermal analyses found that the oxides of lanthanum, cerium, rhodium, and plutonium fluorinated but did not form volatile fluorides and that depending on temperature volatile fluorides formed from the oxides of niobium, molybdenum, ruthenium, tellurium, uranium, and neptunium. We also demonstrated near-quantitative removal of uranium from plutonium in a mixed oxide.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1038367
• Report Number(s): PNNL-SA-80882; JNUMAM; AF5805000; TRN: US1201843
• Journal Information: Journal of Nuclear Materials, 424(1-3):224-236, Vol. 424, Issue 1-3; ISSN 0022-3115
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
ACTINIDES
CERIUM
FISSION PRODUCTS
FLUORIDES
FLUORINATION
LANTHANUM
MOLYBDENUM
NEPTUNIUM
NIOBIUM
NITROGEN
NUCLEAR FUELS
OXIDATION
OXIDES
PLUTONIUM
REMOVAL
REPROCESSING
RHODIUM
RUTHENIUM
SPENT FUELS
TELLURIUM
THERMODYNAMICS
TRANSITION ELEMENTS
URANIUM
URANIUM HEXAFLUORIDE
VOLATILITY