Abstract: Nanocrystalline MgO with a relatively high surface area and mesoporous structure was synthesized by a surfactant assisted precipitation method for use as the support of nickel catalysts for steam reforming of methane. The samples were characterized by X-ray diffraction, N₂ adsorption, temperature-programmed reduction, temperature-programmed oxidation, scanning electron microscopy, and transmission electron microscopy. The catalysts showed high catalytic activity and good stability in the steam reforming of methane. Increasing the nickel loading up to 10 wt% gave increased activity. Catalysts with higher nickel loadings showed more deposited carbon after reaction. The excellent anti-coking performance of the catalysts was attributed to the formation of a nickel-magnesia solid solution, basicity of the support surface, and nickel-support interaction.

Key words: Steam reforming, Carbon deposition, Nickel-magnesia solid solution