The effect of temperature and fuel surface area on spent nuclear fuel dissolution kinetics under H2 atmosphere
Journal article, 2020

In this work we present the results of two spent nuclear fuel leaching experiments in simulated granitic groundwater, saturated with hydrogen under various pressures. The results show a large impact of the dissolved hydrogen already at 1 bar H2 and room temperature on the release of both the uranium and of the fission products contained in the fuel matrix. Based on the results of this study and on published data with fuel from the same rod, the importance of the oxidative dissolution of spent fuel under repository conditions as compared to its non-oxidative dissolution is discussed. The XPS-spectra of the fuel surface before the tests and after long-term leaching under hydrogen are reported and compared to reduced UO2 and SIMFUEL surfaces. The overall conclusion is that in spite of the unavoidable air contamination, hydrogen pressures of 1 bar or higher counteract successfully the oxidative dissolution of the spent nuclear fuel. The stability of the 4d-element metallic particles during fuel leaching under such conditions is also discussed, based on data for their dissolution. The metallic particles are also stable under such conditions and are not expected to release their component metals during long-term fuel leaching. © 2020 The Authors

Nuclear fuels

Fission products

Hydrogen fuels

Hydrogen

Uranium dioxide

Dissolution

Groundwater

Author

Ella Ekeroth

Swedish Nuclear Fuel and Waste Management Company

Studsvik

Michael Granfors

Studsvik

Dieter Schild

Karlsruhe Institute of Technology (KIT)

Kastriot Spahiu

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Nuclear Chemistry

Swedish Nuclear Fuel and Waste Management Company

Journal of Nuclear Materials

0022-3115 (ISSN)

Vol. 531 151981

Subject Categories

Atom and Molecular Physics and Optics

DOI

10.1016/j.jnucmat.2019.151981

More information

Latest update

2/15/2021