The effect of inert gases on the yield and morphology of carbon deposits resulting from methane pyrolysis on fechral catalyst under direct current resistive heating

The effect of the inert component nature (argon, helium) in a gas mixture on the morphology and the amount of carbon deposits formed upon methane pyrolysis on a resistive fechral wire catalyst heated by direct current was studied. The carbon deposits had a similar morphology with fibrous texture in all cases. By varying the gas medium composition, one can obtain either fibers with up to 150 μm length and 2–3 μm diameter or short fibers of 8–10 μm length formed from a dense surface carbon layer. In the presence of helium, the amount of carbon deposited on the surface was virtually proportional to the methane content in the gas mixture, while in argon medium, the carbon formation was markedly retarded.