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Ni catalysts supported on Al_2O_3,ZrO_2-Al_2O_3,CeO_2-Al_2O_3 and ZrO_2-CeO_2-Al_2O_3 were prepared by co- precipitation method,and their catalytic performances for autothermal reforming of methane to hydrogen were investigated. The Ni-supported catalysts were characterized by XRD,TPR and XPS.The relationship between the structures and catalytic activities of the catalysts was discussed.The results showed that the catalytic activity and stability of the Ni/ZrO_2-CeO_2-Al_2O_3 catalyst was better than those of other catalysts with the highest CH_4 conversion,H_2/CO and H_2/CO_x ratio at 750℃.The cat- alyst showed a little deactivation along the reaction time during its 72 h on stream with the mean deactivation rate of 0.08%/h. The catalytic performance of the Ni/ZrO_2-CeO_2-Al_2O_3 catalyst was also affected by reaction temperature,n_(O_2):n_(CH_4) molar ratio and n_(H_2O):n_(CH_4) molar ratio.TPR,XRD and XPS measurements indicated that the formation of ZrO_2-CeO_2 solid solu- tion could improve the dispersion of NiO,and inhibit the formation of NiAl_2O_4,and thus significantly promoted the catalytic activity of the Ni/ZrO_2-CeO_2-Al_2O_3 catalyst.
Ni catalysts supported on Al_2O_3, ZrO_2-Al_2O_3, CeO_2-Al_2O_3 and ZrO_2-CeO_2-Al_2O_3 were prepared by co-precipitation method, and their catalytic performances for autothermal reforming of methane to hydrogen were investigated. The Ni-supported catalysts were characterized by XRD , TPR and XPS. The relationship between the structures and catalytic activities of the catalysts was discussed. The results showed that the catalytic activity and stability of the Ni / ZrO_2-CeO_2-Al_2O_3 catalyst was better than those of other catalysts with the highest CH_4 conversion. , H 2 / CO and H 2 / CO_x ratio at 750 ° C. The cat-alyst showed a little deactivation along the reaction time during its 72 h on stream with the mean deactivation rate of 0.08% / h. The catalytic performance of the Ni / ZrO 2 The molar ratio of n_ (CH_4) to n_ (H_2O): n_ (CH_4) molar ratio.TPR, XRD and XPS measurements indicated that the formation of ZrO_2-CeO_2 solid solu- tion co uld improve the dispersion of NiO, and inhibit the formation of NiAl_2O_4, and thus significantly promoted the catalytic activity of the Ni / ZrO_2-CeO_2-Al_2O_3 catalyst.