Effect of tetragonal ZrO2 on the catalytic activity of Ni/ZrO2 catalyst prepared from amorphous Ni–Zr alloys

In zirconia-supported nickel catalysts, the influence of the ZrO2 phase on the catalytic activity for CO2 methanation has been investigated by TPD and TPR measurements. Ni/ZrO2 catalysts with various amounts of the tetragonal ZrO2 polymorph were prepared from amorphous Ni–Zr alloys by an oxidation–reduction treatment. The fraction of tetragonal ZrO2 in the Ni/ZrO2 catalysts increased with increasing nickel content of the amorphous alloy precursors. The methanation activity of Ni/ZrO2 was strongly influenced by the ZrO2 phase change. The tetragonal zirconia-supported nickel catalysts showed a higher turnover frequency for the methanation reaction and a greater CO2 adsorption than the monoclinic zirconia-supported nickel catalysts.