977.    FISCHER, F., AND BANGERT, F.  [Formation of Carbides Decomposable by Water From Manganese Oxide and Methane at Relatively Low Temperatures.]  Brennstoff-Chem., vol. 10, 1929, pp. 261-265; Ges. Abhandl. Kenntnis Kohle, vol. 9, 1930, pp. 694-706; Chem. Abs., vol. 24, 1930, p. 3453.

     An excess of CH₄ was passed over pulverized oxide (MnO₂ or Mn₃O₄) heated to 800°-1,000°, both with and without admixture of other metallic oxides.  Carbides formed were decomposed by H₂O and by HCl, and the hydrocarbons resulting were measured and analyzed.  Of the admixed oxides, BaO and Al₂O₃ alone favored formation of carbides decomposable by H₂O.  Formation of carbides decomposed by HCl was favored by NiO, Cr₂O₃, and Fe₂O₃.  CeO₂, CaO, TiO₂, CuO, V₂O₅, and K₂CO₃ exerted little or no influence.  The following are conclusions reached:  (1) Carbides are formed by passing CH₄ over the Mn oxides at 800°-1,000°; (2) admixtures of foreign oxides strongly affect the properties of the carbides formed; (3) in the absence of heavy metal oxides, the Mn oxides heated to 800° and above CH₄ give a carbide that will yield 90% of its C as gaseous hydrocarbons on decomposition with H₂O; (4) existence of a previously unknown Mn carbide (Mn₅C₂)x is indicated.