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A series of monolithic Ni/γ-Al_2O_3 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, CH_4/O_2 ratio and space velocity, on the performance of the catalyst were investigated. The results show that at a high space velocity of 1×10~5 h~ -1 , optimal CH_4 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-Al_2O_3 catalyst. The results show that the addition of a small amount of promoters improves the reducibility and activity of the catalyst. The side reaction CH_4+2 O_2→CO_2+H_2O, is fully restrained and 100% H_2 selectivity is achieved when Ce and La are used as promoters, respectively.
A series of monolithic Ni / γ-Al 2 O 3 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, CH_4 / O_2 ratio and space velocity, on the performance of the catalyst were investigated. The results show that at a high space velocity of 1 × 10 ~ 5 h ~ -1, optimal CH_4 conversion can 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-Al_2O_3 catalyst. The results show that the addition of a small amount of promoters improves the reducibility and activity of the catalyst. The side reaction CH_4 + 2 O_2 → CO_2 + H_2O, is fully restrained and 100% H_2 selectivity is achieved when Ce and La ar e used as promoters, respectively.