Combined catalytic partial oxidation and CO2 reforming of methane over ZrO2-modified Ni/SiO2 catalysts using fluidized-bed reactor

Nickel on zirconium-modified silica was prepared and tested as a catalyst for reforming methane with CO2 and O2 in a fluidized-bed reactor. A conversion of CH4 near thermodynamic equilibrium and low H2/CO ratio (1<H2/CO<2) were obtained without catalyst deactivation during 10h, in a most energy efficient and safe manner. A weight loading of 5wt% zirconium was found to be the optimum. The catalysts were characterized using X-ray diffraction (XRD), H2-temperature reaction (H2-TPR), CO2-temperature desorption (CO2-TPD) and transmission election microscope (TEM) techniques. Ni sintering was a major reason for the deactivation of pure Ni/SiO2 catalysts, while Ni dispersed highly on a zirconium-promoted Ni/SiO2 catalyst. The different kinds of surface Ni species formed on ZrO2-promoted catalysts might be responsible for its high activity and good resistance to Ni sintering.