Abstract
The catalytic effect of iron, nickel, austenitic high-temperature steels and refractory materials on the pyrolytic reaction of CH4 has been studied by thermogravimetry and gas chromatography. Metallographical observations and gas analysis indicated that refractory brick had the most significant effect on pyrolytic reaction of CH4 because of its high porosity and because it contains a considerable amount of iron oxide which catalyzed the reaction. The catalytic effect of metal specimens was largest at the early stages, but decreased as non -catalytic products such as carbon, stable carbides and oxides occurred on the surface. Cracking and spalling of these products resulted in a local catalytic effect. The higher the concentration of iron in the high-temperature steels, the larger the catalytic effect, because iron catalyzes more actively than nickel.
