Recycling processes of large grain UO_2 pellet scrap was studied by modifying the processing parameters such as the oxidizing temperatures to make the oxidized U_3O_8 powders, repetition of reducing and then re-oxidizing the oxidized U_3O_8 powders, and a mild milling of the oxidized U_3O_8 powder. Recycled U_3O_8 powder with a high BET surface area and a small particle size could be obtained by oxidizing the large grain pellets at low temperature and then applying reduction-and-oxidation process. It was also found that recycled U_3O_8 powder having high BET surface area was very effective in preventing the grain size reduction in recycled U_3O_8 added large grain UO_2 pellets.
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