Leaching Behaviour of Dysprosium-Doped (U,Dy)O2 LVRF Fuel Under CANDU Coolant Conditions

Abstract

Experiments were carried out to determine the leaching behaviour of the dysprosium-doped fuels (U,Dy)O₂) in chemistry conditions close to that of the coolant in CANDU reactors. Leaching tests were also carried out with preoxidized UO₂ and (U,Dy)O₂ fuel samples oxidized under conditions selected to oxidize UO₂ to UO_2.1. Leaching tests were also carried out in the presence of coupons made of the pressure tube material to study its effect on fuel leaching. The results of the tests indicate that very little dysprosium is leached out from the dysprosium-doped fuels under the coolant conditions used in the CANDU reactors.