Patent Number: 062513109
Section: claims

1. A method of producing a UO.sub.2 -based fuel pellet from an irradiated UO.sub.2 -based fuel pellet, the method comprising: heating an irradiated UO.sub.2 -based fuel pellet in an oxidizing gas, to produce a U.sub.3 O.sub.8 -based product,  mixing the U.sub.3 O.sub.8 -based product with an additive comprising at least one oxide of an element selected from the group consisting of Nb, Ti, V, Al, Mg, Cr, Si and Li, to produce a mixture,  pressing the mixture into a green pellet, and  sintering the green pellet in a reducing gas atmosphere to reduce the U.sub.3 O.sub.8 -based product to a UO.sub.2 -based product. 2. The method of claim 1, wherein said heating step is carried out at a temperature in the range of about 300.degree. C. to about 700.degree. C. 3. The method of claim 1, wherein said mixing step further comprises mixing fresh UO.sub.2 -based powder with the U.sub.3 O.sub.8 -based product, the additive or the mixture. 4. The method of claim 1, wherein the additive is mixed with the U.sub.3 O.sub.8 -based powder in an amount of about 0.02% to 5% by weight of the mixed powder. 5. The method of claim 1, wherein said sintering step comprises heating the green pellet to a temperature of at least 1500.degree. C. for at least 1 hour in a reducing gas atmosphere. 6. The method of claim 1, wherein the reducing gas comprises at least one gas selected from the group consisting of (i) hydrogen, (ii) a mixture of hydrogen and at least one inert gas, (iii) a mixture of hydrogen and carbon dioxide, and (iv) a mixture of hydrogen and steam.