[en] Increasing the reactivity of the major component, TiO₂, of oxide route Synroc precursor, led to a significant reduction in the hot pressing temperature required to achieve near-theoretical density. The combination of Ba and Ca hydroxides and a more reactive Al₂O₃ resulted in leach rates for Cs which approach those of alkoxide-route precursors. This improvement is believed to have been brought about by the dissolution of Al(OH)₃ in the highly alkaline slurries created when Ca and Ba hydroxides are used. This increased availability of Al³⁺ allows for the formation of more hollandite, into which the Cs can be incorporated, thus reducing the Cs leach rates. The use of a static mixer for waste addition improved the metallic phase distribution but did not affect the leach results. (author) 1 fig., 4 tabs., 10 refs