X-ZrO2 addition (X = Ce, La, Y and Sm) on Ni/MgAl2O4 applied to methane tri-reforming for syngas production

Nickel supported on MgAl2O4 spinel (Ni/MA) and the effects of X-ZrO2 (X = Ce, La, Sm and Y) addition to the support were studied in Methane Tri-Reforming (MTR) process. The characterization techniques employed were XRD, B.E.T., H-2-TPR, H-2-TPD, CO2-TPD, XPS, and in situ XANES. The presence of lanthanides and Y associated to ZrO2 modified the Ni-0 dispersion and the surface basicity. These properties influence the coke formation, which increased as the metallic dispersion diminished. Ce-ZrO2 association on the spinel support led to the greatest catalytic performance, increasing reactants conversions due to its adequate base properties that allowed the adsorption of new reactants molecules due to coke elimination, associated to its smallest apparent Ni-0 average size. Moreover, the Ce-Zr support favored the NiO activation, without compromising the nickel dispersion.