2238.     MERCK, F., AND WEDEKIND, E.  [Magnetic Analytic Investigation of Cobalt Oxide as Catalyzer of Carbon Monoxide Combustion at Room Temperature.]  Ztschr. anorg. Chem., vol. 186, 1930, pp. 49-74; Chem. Abs., vol. 24, 1930, p. 2036.

        It is concluded that the cobaltic oxide catalyzer consists essentially of 2 crystalline phases, CoOOH and CO3O4, Co2O3 being chiefly converted into the latter.  Of these 3, the components CoOOH and Co3O4 are catalytically ineffective.  The cobaltic oxide in the Co3O4 lattice is superficially reduced by the diluted CO.  Magnetic measurements were made by Wedekind’s microchemical method (see abs. 3619) and show that magnetism increases in going from hydrate to oxide.  For Co3O4, x is about 32 x 10-6 and varies relatively little as the titratable O content varies.  In the transformation from hydrate to oxide, an active intermediate state is present, characterized by a dependence of susceptibility upon field strength.  This vanishes on sintering and also on aging with partial reconversion into hydrate.  At room temperature the hydrate is more stable than oxide+H2O.