952.    ---------------.  [FISCHER, F.]  [Formation at Relatively Low Temperatures of Carbides Yielding Acetylene.]  Brennstoff-Chem., vol. 9, 1928, pp. 328-333; Chem. Abs., vol. 23, 1929, p. 2662.

     BaC2 is prepared from BaO by heating with C in an electric porcelain-tube furnace in a stream of CH4, with or without the addition of a small quantity of Fe2O3 and CaO.  BaC2 yielding 60% of the theoretical C2H2, was obtained by heating a mixture of 2 gm. BaO+1 gm. CaO+0.2 gm.  Fe2O3 for 30 min. at 1,150 in CH4 at 35 mm. pressure.  Carbides were not formed below 850 and yields fell sharply above 1,150.  The highest yields were obtained in an atmosphere of CH4.  The carbide formed at these low temperatures yields both H2 and C2H2 with H2O.  Fischer believes that free Ba is first formed by reduction, and this is partly converted into BaC2 and partly into BaH4.