A FTIR and QMS study of methanol decomposition, pure
or with water and oxygen, on two gold catalysts, Au/ZnO and
Au/TiO2, has been performed in the temperature range 300 − 523 K. The role of O2 on Au particles near oxygen vacancies of the supports in the oxidative dehydrogenation of CH3OH is
discussed. Differences on the nature and the thermal stability of the surface intermediates have been evidenced, depending on the gas phase composition. The goal was to verify the perspectives of Au catalysts differently supported in the decomposition of methanol, hence in H2 production. Moreover, CO oxidation and preferential oxidation in the presence of an excess of H2 (PROX) from 90 K up to 500 K on the same catalysts have been undertaken, looking at H2 purification for fuel cell applications. CO oxidation and PROX on these catalysts provide an insight on the origin of the regeneration effect of hydrogen. The presence of H2 in the mixture inhibits the formation of transient intermediates and of carbonates at the interface between the metal and the oxide. An effect of the different acidity/ basicity of the supports has also been evidenced.