Steam reforming of methane over nickel catalysts at low reaction temperature Original Research Article

Effects of supports such as silica, γ-alumina, and zirconia for nickel catalysts have been studied in steam reforming of methane at 500 °C. The activity of nickel supported on silica reduced with hydrogen at 500 °C decreases with oxidation of nickel particles by steam during the reaction. Nickel supported on γ-alumina is not much reduced with hydrogen at 500 °C and is inactive in the reforming at 500 °C. However, the catalyst reduced at 700 °C is fairly active while nickel is partially oxidized during the reaction. Nickel supported on zirconia is the most effective in the stream reforming at 500 °C. In the initial stage of the reaction solely with methane at 500 °C, surface hydroxyl groups on these catalysts react readily with methane to produce hydrogen and carbon dioxide; suggesting that the hydroxyl groups play an important role in the mechanism of the steam reforming to carbon dioxide. A significant quantity of water can be accumulated on the surface of zirconia-supported nickel in the reaction only with steam at 500 °C, and this results in formation of significant quantities of hydrogen and carbon dioxide in the following reaction with methane.