IMPREGNATION OF GRAPHITE WITH URANIUM COMPOUNDS FOR USE AS FUEL ROD MATERIALS

A process hns been developed for impregnating graphite with U/sub 3/O/ sub 8/ in connection with the proposed use of such material for fuel rod elements in the Daniels' High Temperature Pile. The process as developed consists of five steps: Fabrication of the graphite in the desired shape; Pretreatment of the graphite by boiling in water and then firing in helium at 800 deg C; Impregnating the graphite by first evacuating the pretreated material and then admitting an aqueous uranyl nitrate solution whose concentration is etermined by the final uranium content desired in the raphite; Drying the impregnated graphite slowly under quilibrium conditions; and Conversion of the uranyl itrate to U/sub 3/O/sub 8/ by firing in helium at 800 deg C. By this process fuel rod elements have been made which contain as much as 19% U/sub 3/O/sub 8/ distributed uniformly throughout the graphite. The considerations leading to the choice of this process are discussed in this report, together with the alternate procedures which were investigated. (auth