An array of Pd, Fe and Ir exchanged β-zeolites were synthesized, fully characterized, and their catalytic activity evaluated in converting bio-derived compounds to value-added platform chemicals.

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Herein, a sol-gel one-pot methodology to tune the activity of Co-catalysts supported on silica-titania to CO oxidation is described. SEM, TEM, EDS, XPS and H 2-TPR evidenced a higher Co dispersion from that method when compared to catalysts prepared by impregnation. Furthermore, the simultaneous addition of cobalt oxalate during the incorporation by sol-gel of a controlled low Ti amount into the silica (Si/Ti = 5.7) was determinant to improve the Co dispersion and to avoid the formation of Co-species with strong support interaction. Moreover, XPS analyses evidenced that the mentioned low Ti amount favoured a higher formation of superficial Co 3+ and lattice O 2− species, which promoted a higher CO oxidation specific activity and, more importantly, strongly decreasing the light-off temperature. On the other hand, Rietveld analyses, Raman spectroscopy, H 2-TPR and XPS data showed that the incorporation of higher amounts of Ti into the silica (Si/Ti = 0.2) led to the formation of cobalt titanate, decreasing the concentration of superficial Co 3+ and lattice O 2− species and, consequently, decreasing the specific activity toCO oxidation.

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Cobalt catalysts supported on tetragonal and monoclinic zirconia were prepared using a one‐pot procedure through the incorporation of a Co3O4 colloidal suspension during the support synthesis and evaluated in the reaction of NO reduction by CO. A better dispersion of the active phase was obtained by this method when compared to the conventional impregnation one. Furthermore, the crystalline phase of zirconia in the supports had a crucial effect in the dispersion of the cobalt species, being that the pure tetragonal phase led to a higher dispersion of the active phase. The one‐pot prepared tetragonal zirconia led to cobalt active species that consisted in well‐dispersed small agglomerates of Co3O4 and Co2+ species as oxo‐ions which displayed the best catalytic performance among the studied catalysts, with the highest NO conversion (75%) and high selectivity to N2 (85%) at 300 °C. These results show that the one‐pot methodology employed in this work has a strong potential to produce suitable catalysts for the abatement of NOx emissions.