Fabrication of Carbon-dispersed $UO_3$ Microspheres by an Internal Gelation

An internal gelation process was adopted for the fabrication of carbon-dispersed UO$_3$ microspheres which will be fed to the fabrication for uranium nitride microsphere fuels by the carbothermic reduction. For investigating the proper process conditions, a composition range of feed solution for preparing good UO$_3$ gel spheres was firstly defined by observing the gelation behavior. Within the defined solution compositions, carbon-dispersed microspheres were prepared and carbon distribution in microspheres were observed by SEM. The results showed that production of good carbon-dispersed microspheres was possible, and the most of carbon were evenly distributed in the microspheres although large carbon-rich aggregates were sparsely existent.