Skip to main content Accessibility help

Leaching Behavior of Unirradiated High Temperature Reactor (HTR) UO2-ThO2 Mixed Oxides Fuel Particles

  • Catherine Landesman (a1), Sandra Delaunay (a1) and Bernd Grambow (a1)


The dissolution rate of small UO2, ThO2 and mixed UO2–ThO2 particles, representative of unirradiated HTR fuel, are investigated in the pH range 1.7 to 5.5 under oxic conditions. For UO2 particles, the dissolution is kinetically control while for ThO2 particles, a solubility control mechanism seems to prevail for pH > 2. In the mixed oxides UO2–ThO2 particles, a selective release of uranium is observed, which could be either the result of a dissolution/precipitation mechanism in which thorium reprecipitate as oxide or hydroxide phase, or a result of a higher accessible surface area. Under oxic conditions, uranium may be considered as a tracer for the other soluble elements. So, assuming constant conditions with time, one can estimate from these preliminary results that unirradiated thorium based fuel kernels seem to present intrinsic confinement properties for 15000 years relative to soluble elements.



Hide All
1. Nickel, H., Nabielek, H., Pott, G., Mehner, A.W., Nuclear Eng. Design 27, 141151 (2002)
2. Schenk, W., Naoumidis, A., Nickel, H., Journal of Nuclear Materials 24, 2532 (1984)
3. Schenk, W., Pott, G., Nabielek, H., Jounal of Nuclear Materials 7, 1930 (1990)
4. Grambow, B., Loida, A., Martinez-Esparza, A., Dias-Arocas, P., de Pablo, J., Paul, J.L., Marx, G., Glatz, J.P, Lemmens, K., Ollila, K., Christensen, H., European Commission EUR 19140 EN, 2000, Brussels
5. Hubert, S., Barthelet, K., Fourest, B., Lagarde, G., Dacheux, N., Baglan, N., Journal of Nuclear Materials, 297, 206213 (2001)
6. Neck, V., Kim, J.I., Radiochimica Acta, 89, 116 (2001)


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed