974.    ---------------.  [FISCHER, F AND BAHR, H.]  [Decomposition of Methane at Various Temperatures on Various Catalysts.]  Ges. Abhandl. Kenntnis Kohle, vol. 8, 1929, pp. 274-279; Chem. Zentralb., 1930, I, p. 31; Chem. Abs., vol. 25, 1931, pp. 2411-2412.

     When a gas mixture rich in CH4 (natural gas from Altengamme with 92.5% CH4) was conducted through a heated quartz tube or through a heated porcelain tube, which was empty or filled with porcelain fragments, the decomposition started at 850 with deposition of C on the tube walls and with the formation of H2, tar mist, and a slight quantity of small C10H8 crystals.  When moist CH4 is used, the quantity of the H2 formed is almost twice that with dry CH4 (34.3:19.1%).  With finely distributed graphite as a catalyst, no tar and only very little C10H8 is formed.  With BaSO4 as a catalyst H2O and H2S are formed at 630-650; in this case also traces of an unsaturated hydrocarbon were noticed.  The latter was also obtained when BaO was used.  CH4 is also decomposed when its presence in the gas current amounts to only 15%; in this case traces of C6H6 were noticed, which was identified as PhNO2.  When ZnO with addition of 1% K2O in the form of K2CO3 was used, the CH4 decomposition began at 700; at 850 the increase in volume of the gas was 50.9% and remained the same when the velocity of the current was reduced from 2-5 l. per hr. to 0.5 l. per hr., but it was considerably lessened when the velocity of the current was increased to 6 l. per hr.