Partial Oxidation of Methane to Syngas over Monolithic Ni/γ-Al₂O₃ Catalyst——Effects of Rare Earths and Other Basic Promoters

【Abstract】 A series of monolithic Ni/γ-Al₂O₃ catalysts with and without basic promoters （Na, Sr, La, Ce） were prepared. Partial oxidation of methane （POM） to syngas was carried out in a continuous-flow, fixed-bed reactor. The influences of reaction conditions, including temperature, CH₄/O₂ ratio and space velocity, on the performance of the catalyst were investigated. The results show that at a high space velocity of 1×10⁵ h -1 , optimal CH₄ conversion can be obtained. Effects of promoters such as Na, Sr, Ce, La were also investigated, and the catalyst samples were characterized by means of temperature-programmed reduction and XRD techniques. XRD suggests that the addition of promoters has no influence on the crystal structure of Ni/γ-Al₂O₃ catalyst. The results show that the addition of a small amount of promoters improves the reducibility and activity of the catalyst. The side reaction CH₄+2 O₂→CO₂+H₂O, is fully restrained and 100% H₂ selectivity is achieved when Ce and La are used as promoters, respectively.更多还原