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.