Effect of MgO addition on the basicity of Ni/ZrO2 and on its catalytic activity in carbon dioxide reforming of methane

The effect of the MgO content on the basicity and on the catalytic performance of Ni/ZrO2-MgO catalysts for carbon dioxide reforming of methane was studied. MgO addition to the zirconia support by co-precipitation (5% MgO) had several effects: stabilized the zirconia tetragonal phase by increasing its thermal stability, increased the basicity of the support, and decreased the reducibility of Ni2+. The CO2 desorption energy distribution functions calculated from the TPD-CO2 profiles were centred at activation energies around 100-134 kJ mol(-1). Besides the effect due to the modification of the zirconia properties by MgO addition, the catalytic activity was also related to the reduction degree of nickel on Ni/ZrO2-MgO catalysts, while the catalyst stability was related to the basic properties of the supports. (C) 2009 Elsevier B.V. All rights reserved.