Catalytic performance of nickel-based catalysts with different supports in partial oxidation of methane to synthesis gas

A series of Ni-based catalysts with different supports (Al₂O₃, ZrO₂, CeO₂, CeO₂-Al₂O₃ and ZrO₂-Al₂O₃) were prepared by the methods of impregnation. The effects of supports on the physical structures and catalytic performance of the resultant catalysts in partial oxidation of methane (POM) were investigated. The catalysts were characterized by N₂ physical adsorption, X-ray diffraction, temperature programmed reduction by hydrogen, temperature programmed desorption of ammonia and temperature programmed oxidation. The results showed that the Ni/Al₂O₃ catalyst had a large BET specific surface area and high initial activity. However, the Ni/Al₂O₃ catalyst showed a serious deactivation due to the formation of large amount of carbon deposited on the surface of the catalyst. Ni/ZrO₂ and Ni/CeO₂ catalysts displayed low activity, which resulted from its low BET specific surface area and poor NiO dispersion. The Ni/ZrO₂-Al₂O₃ catalyst showed high activity and the Ni/CeO₂-Al₂O₃ catalyst exhibited the best activity and coking resistance among the catalysts. CeO₂ could effectively suppress carbon formation and the transformation to inactive carbon species, due to the oxygen storage and release ability.