3503.     ---------------.  [TUTIYA, H.]  Catalytic Decomposition of Carbon Monoxide.  II.  Is the So-Called X-Carbide Really Formed in the Iron Catalyst?]  Bull. Inst. Phys. Chem. Research (Tokyo), vol. 8, 1929, pp. 609-613, abs. sec. 2, pp. 76-77; Chem. Abs., vol. 24, 1930, p. 3159.

        X-ray spectrograms of specimens of Fe carbide and Fe2O3 used as catalysts in the decomposition of CO gave no evidence of the formation of new compounds.  The photograms of samples of Fe2O3 taken at suitable stages of the reaction showed evidence of the successive reduction to the oxides Fe3O4 and FeO and later to Fe3C.  It was found that almost all the lines of strong intensity, which Hofmann (abs. 1455) ascribed to the X-carbide, agreed with those of Fe3O4, not only in position, but also in order of intensity; one of the weak lines, which was not common to Fe3O4, was due to FeO, and 2 were shown by Fe2O3.