1084.    ---------------.  [FRAZER, J. C. W.] Catalytic Oxidation of Carbon Monoxide.  Jour. Phys. Chem., vol. 35, 1931, pp. 405-411; Chem. Abs., vol. 25, 1931, p. 1432.

       Carefully purified, finely divided MnO₂, Co₂O₃, and Ni₂O₃ are extremely active catalysts for the union of CO and O₂ at temperatures as low as 0°.  Extreme purity, not the presence of promoters, is important for catalytic activity.  Impurities may be removed by electrolysis of an aqueous suspension of the oxides.  None of 17 other unnamed oxides studied was effective.  the 3 active oxides differ from the others in 1 significant particular, namely, their composition is indefinite.  By an adsorption apparatus it was shown that the O₂ pressure in equilibrium with a sample of one of these oxides depends on the composition of the oxide.  Condensation of water vapor within the pores of these oxides destroys their catalytic activity.  Extreme drying does not destroy the activity.