[en] The sol-gel process as developed by the O.E.C.D. Dragon Project has been applied by the Plutonium Project at Mol to determine the feasibility of producing spherical particles containing ThO₂, PuO₂ and C, in the proportions necessary to fabricate thorium-plutonium carbide kernels for irradiation specimens and for fuel cartridges for the Dragon Reactor Experiment. The process has been extended successfully to the preparation of thorium and plutonium gels, having a significant excess of carbon, with the object of evaluating the feasibility of the sol-gel process for the production of ''Th, C-10'' and ''Pu, C-10'' type kernels. Other experiments have been performed to test the feasibility of incorporating UO₂ powder into the gel spheres. By using this technique, U to Th ratios of up to 9:1 have been obtained. (author)