459.    CHAKRAVARTY, K. M., AND CHAKRAVARTY, P. B.  Effect of Potassium Carbonate on Nickel Catalysts for the Fischer-Tropsch Synthesis.  Sci. and Culture, vol. 12, 1946, pp. 110-111; Chem. Abs., vol. 41, 1947, p. 1989.

                 Catalysts containing traces of K₂CO₃ were found to lose their activity after passage of small volumes of H₂-CO mixture.  The deactivated catalyst, after being washed with distilled water and reduced at 200°, was negligibly active at first but rose in activity to a steady value somewhat below that found with the original preparation.  The catalyst composition was:  Kieselguhr, 46%; Ni, 45.77%; ThO₂, 8.3%; and K₂CO₃, traces.  A similar preparation containing 0.0823% CeO₂ behaved in the same manner; the reactivated catalyst was not very active at 178°-180° but was steadily active at 219°-220°.  The presence of K₂CO₃ causes the formation of C, CO₂, and H₂O rather than hydrocarbons.