Partial oxidation of methane on Pt catalysts: Effect of the presence of ceria–zirconia mixed oxide and of metal content

The objective of this work was to study the effects of different noble metal loadings on Pt/CeZrO2/Al2O3 catalysts for the partial oxidation of methane. For both Al and CeZrAl series of samples, the decrease of platinum loading resulted in a significant increase of metallic dispersion. Temperature-programmed reduction and oxygen storage capacity analyses revealed that the sample containing 1.5% Pt presented superior redox properties when compared to the other samples. The catalytic tests showed that the use of smaller Pt contents lead to deactivation. X-ray absorption near edge structure experiments showed that all Pt is in the reduced form above 600 °C. In addition, there is evidence that the partial oxidation of methane proceeds through a two-step mechanism. The best performance was obtained for the 1.5Pt/CeZr/Al catalyst that has the largest platinum content, the presence of a homogeneous solid solution, good metal dispersion and high BET surface area.

This work evaluated the effects of different noble metal loadings on Pt/CeZrO2/Al2O3 catalysts for the partial oxidation of methane. The use of smaller Pt contents leads to deactivation. The best performance was obtained for the 1.5Pt/CeZr/Al catalyst that has the largest platinum content, the presence of a homogeneous solid solution, good metal dispersion and high BET surface area.Figure optionsDownload as PowerPoint slide