Combined catalytic partial oxidation and CO 2 reforming of methane over ZrO 2-modified Ni/SiO 2 catalysts using fluidized-bed reactor

Abstract

Nickel on zirconium-modified silica was prepared and tested as a catalyst for reforming methane with CO 2 and O 2 in a fluidized-bed reactor. A conversion of CH 4 near thermodynamic equilibrium and low H 2/CO ratio (1<H 2/CO<2) were obtained without catalyst deactivation during 10 h, in a most energy efficient and safe manner. A weight loading of 5 wt% zirconium was found to be the optimum. The catalysts were characterized using X-ray diffraction (XRD), H 2-temperature reaction (H 2-TPR), CO 2-temperature desorption (CO 2-TPD) and transmission election microscope (TEM) techniques. Ni sintering was a major reason for the deactivation of pure Ni/SiO 2 catalysts, while Ni dispersed highly on a zirconium-promoted Ni/SiO 2 catalyst. The different kinds of surface Ni species formed on ZrO 2-promoted catalysts might be responsible for its high activity and good resistance to Ni sintering.