Hydrogen production in steam reforming of methane at low reaction temperature over nickel catalysts

摘要

Effects of supports to nickel catalysts have been studied for the steam reforming of methane at 773 K. The activity of nickel supported on silica reduced with hydrogen at 773 K decreases with oxidation of nickel particles by steam during the reaction. Nickel supported on alumina is scarcely reduced with hydrogen at 773 K and inactive in the reforming at 773 K. However, the catalyst reduced at 973 K is fairly active while nickel is partially oxidized during the reaction. In absence of steam, surface hydroxyl groups on these catalysts react with methane at 773 K to produce hydrogen and carbon dioxide, suggesting that the hydroxyl groups play an important role in the low temperature reforming. In the case of zirconia-supported nickel, water accumulated on the surface at 773 K involves in the reaction with methane and the catalyst is the most effective in the stream reforming at 773 K.