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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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New coolants, new fuels: A new generation of university reactors
Here’s an easy way to make aging U.S. power reactors look relatively youthful: Compare them (average age: 43) with the nation’s university research reactors. The 25 operating today have been licensed for an average of about 58 years.
D. L. Smith
Nuclear Technology | Volume 20 | Number 3 | December 1973 | Pages 190-199
Technical Paper | Fuel | doi.org/10.13182/NT73-A31357
Articles are hosted by Taylor and Francis Online.
The oxygen concentration of sodium in equilibrium with uranium-25% plutonium oxide fuel has been measured at temperatures of 650 to 900°C for fuels with oxygen-to-metal ratios of 1.90, 1.94, and 1.97. The oxygen concentration in sodium at the three-phase Na-MO2-x-Na3MO4 (M = uranium plus plutonium) equilibrium has also been measured for the same temperature range. This three-phase equilibrium was established by reacting mixed-oxide fuel with sodium to which Na2O had been added. The oxygen concentrations in sodium were determined by the vanadium-wire equilibration method. The oxygen concentration in sodium at the three-phase equilibrium varied from ∼0.1 to 0.4 ppm in the temperature range investigated. Oxygen concentrations in EBR-II primary sodium, which have been measured by the same method, vary from 0.4 to 0.9 ppm oxygen depending on the cold-trap operation. These values indicate that the sodium -fuel reaction product, i.e., Na3MO4, is stable in sodium at the temperatures (<1000°C) and oxygen levels present in EBR -II.
