In:
MRS Proceedings, Springer Science and Business Media LLC, Vol. 807 ( 2003)
Abstract:
The dissolution rate of small UO 2 , ThO 2 and mixed UO 2 –ThO 2 particles, representative of unirradiated HTR fuel, are investigated in the pH range 1.7 to 5.5 under oxic conditions. For UO 2 particles, the dissolution is kinetically control while for ThO 2 particles, a solubility control mechanism seems to prevail for pH 〉 2. In the mixed oxides UO 2 –ThO 2 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.
Type of Medium:
Online Resource
ISSN:
0272-9172
,
1946-4274
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2003
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