摘要 |
A method for fabricating porous UO2 sintered pellets to be fed into an electrolytic reduction process for the purpose of metallic nuclear fuel recovery is provided, which includes forming a powder containing U3O8 by oxidizing a spent nuclear fuel containing uranium dioxide (UO2) (step 1), fabricating U3O8 green pellets by compacting the powder formed in step 1 (step 2), and fabricating UO2 sintered pellets by sintering the U3O8 green pellets fabricated in step 2 at 1000 to 1600° C., in an atmospheric gas, and cooling the same for reduction, by changing the atmosphere to a reducing atmospheric gas (step 3). The porous UO2 sintered pellets can be fabricated, which do not have any defects. The volatile fission products are sufficiently removed from the fabricated porous UO2 sintered pellet, the O/U ratio is 2.00, the permeation of the electrolyte during reduction is facilitated, and the electrolytic reduction velocity increases.
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