3506.     ---------------.  [TUTIYA, H.]  Catalytic Decomposition of Carbon Monoxide.  V.  Behavior of Molybdenum Carbides.  Bull. Inst. Phys. Chem. Research (Tokyo), vol. 11, 1932, pp. 1136-1149; Sci. Papers Inst. Phys. Chem. Research (Tokyo), vol. 19, No. 384-392, 1932; Chem. Abs., vol. 27, 1933, p. 1809.

        CO was decomposed under various conditions in presence of metallic Mo, its carbides or solid solution of Mo₂C, and solid phases formed of carbides and C were examined by the X-ray method.  Mo₂C is formed at 450°-600°; a very diffused diffraction line of C (002) is observed in the powder spectrogram of the reaction product at 600°.  Mo and its carbides are not oxidized in CO at 450°-800°; CO flowing over the mixture of Mo₂C and C is decomposed at 600°, C itself having no catalytic property.  A new carbide phase, most probably MoC, is formed at 750°.  At 750°-800°, the mixture of Mo₂C, and C is formed, and CO is decomposed without the existence of metallic Mo; the reaction product at 650°-700° contains, besides Mo₂C, a metastable carbide phase.