The methane autothermal reforming in the present of oxygen was studied over cerium- and zirconium-promoted Ni/SiO2 catalysts in a fluidized bed reactor. The addition of CeZrO2 resulted in a significant improvement in ...The methane autothermal reforming in the present of oxygen was studied over cerium- and zirconium-promoted Ni/SiO2 catalysts in a fluidized bed reactor. The addition of CeZrO2 resulted in a significant improvement in the initial activity of the catalysis as well as an increase in the stability. The long-term activity of the promoted catalyst was dependent upon the rapid redox properties between the oxidative zone and the reductive zone in a fluidized bed reactor. H2 temperature-programmed reduction （H2-TPR） and face reaction （TPSR） studies demonstrated that addition of the CeZrO2 resulted in an increase in the reducibility and oxygen transfer ability of the support, Ni/Ceo.5ZrO0.5O2-SiO2 showed improved redox properties compared with Ni/SiO2 due to a low-temperature reduction. X-ray diffraction （XRD） of the fresh and spent catalysts showed that the promoter enhanced the nickel dispersion and retarded metal particle growth during reaction at high temperature, and surface Ni was gradually oxidized by remaining O2, leading to Ni deactivation.展开更多
基金supported by the New Century Excellent Talents in University of Henan Province (2006HANCET-20)the National Natural Science Foundation of China (20433030)
文摘The methane autothermal reforming in the present of oxygen was studied over cerium- and zirconium-promoted Ni/SiO2 catalysts in a fluidized bed reactor. The addition of CeZrO2 resulted in a significant improvement in the initial activity of the catalysis as well as an increase in the stability. The long-term activity of the promoted catalyst was dependent upon the rapid redox properties between the oxidative zone and the reductive zone in a fluidized bed reactor. H2 temperature-programmed reduction （H2-TPR） and face reaction （TPSR） studies demonstrated that addition of the CeZrO2 resulted in an increase in the reducibility and oxygen transfer ability of the support, Ni/Ceo.5ZrO0.5O2-SiO2 showed improved redox properties compared with Ni/SiO2 due to a low-temperature reduction. X-ray diffraction （XRD） of the fresh and spent catalysts showed that the promoter enhanced the nickel dispersion and retarded metal particle growth during reaction at high temperature, and surface Ni was gradually oxidized by remaining O2, leading to Ni deactivation.
