Sol-Gel processes were successfully used to obtain (Th,U)O2 microspheres with the properties required for its use in HTGR reactors. The Hydrolysis Process was used to obtain UO2 microspheres, and the External Gelation Process was used to obtain (Th,0-25%U)O2 microspheres. Optimization of synthesis conditions is still required for the Hydrolysis Process.
HTGR; uranium oxide; thorium oxide; sol-gel; microspheres