Structural and catalytic properties of Au/MgO-type catalysts prepared in aqueous or methanol phase: application in the CO oxidation reaction

Au/MgO and Au/Mg(OH)(2)-type catalysts for CO oxidation reaction were prepared by using two different synthesis methods in presence of either an aqueous or methanol phase. The influence of the porous and morphological properties of the starting magnesium oxide supports was analyzed and correlated with the catalytic performances of the final gold-supported catalysts. It was found…

Monitoring the Reaction Mechanism in Model Biogas Reforming by InSitu Transient and Steady-State DRIFTS Measurements

In this work, the reforming of model biogas was investigated on a Rh/MgAl2O4 catalyst. In situ transient and steady-state diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) measurements were used to gain insight into the reaction mechanism involved in the activation of CH4 and CO2. It was found that the reaction proceeds through of an initial pathway in which…

Gold promoted Cu/ZnO/Al2O3 catalysts prepared from hydrotalcite precursors: Advanced materials for the WGS reaction

Outstanding catalysts for the water was shift reaction are reported in this work. The combination of gold nanoparticles with Cu/ZnO/Al2O3 prepared from hydrotalcite-like precursors leads to very promising systems for pure hydrogen production. Full CO conversion is reached at temperatures as low as 180 degrees C. The key point seems to be the cooperation of…

Gold catalysts screening in base-free aerobic oxidation of glucose to gluconic acid

Base-free aerobic oxidation of glucose in presence of Au/Al2O3, Au/CeO2, Au/CeO2(20 wt%)/Al2O3, Au/CeO2(25 wt%)/ZrO2 and Au/CeO2(50 wt%)/ZrO2 catalysts using molecular oxygen at atmospheric pressure is studied. Within the whole series high conversion and selectivity to gluconic acid are observed after 18 h of reaction at 120 degrees C. The activity and especially the selectivity changes…

Selectivity control in oxidation of 1-tetradecanol on supported nano Au catalysts

Selective oxidation of tetradecanol, a model higher fatty alcohol, on Au/CeO2-Al2O3 catalyst has been investigated to assess the factors that control selectivity. The analysis of the effect of operation conditions (temperature, run time and alcohol/metal (AIM) ratio) on catalytic performance revealed a quite complex reaction network, in which acid formation starts only after a certain…

WGS and CO-PrOx reactions using gold promoted copper-ceria catalysts: «Bulk CuO-CeO2 vs. CuO-CeO2/Al2O3 with low mixed oxide content»

A copper-ceria bulk catalyst has been compared to a series of catalysts designed according to the as called «supported approach», corresponding to the dispersion of low content mixed copper-ceria oxide on alumina matrix. The principal characteristics of both types of catalysts are contemplated and the differences in their electronic and redox properties discussed in details.…