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Sodium mordenites and beta zeolites, partially exchanged with Cu2`, were characterised by means of Fourier transform infrared (FTIR) and both continuous-wave and pulse electron paramagnetic resonance (EPR) spectroscopies, in order to shed light on the catalytic role of copper ions in the ammoxidation of 1-methylnaphthalene. FTIR analysis showed that ammonia interacts with both and Lewis acid sites, while 1-methylnaphthalene is mainly coordinated through n-complexes. The acidity of the BrÔnsted catalysts was also determined through FTIR analysis of the adsorbed pyridine. The main changes in the coordination sphere of Cu2`ions were observed by EPR analysis after ammonia adsorption and after catalyst use, while adsorption of 1methylnaphthalene had a very minor e †ect. Primary electron spin echo envelope modulation spectra after catalytic use showed the presence of organic radicals, having a relaxation time of longer than the Cu2`ions. The latter are conÐrmed as the active reaction centres and should be located in the side pockets of the mordenites, and be unaccessible to the aromatic system of 1-methylnaphthalene. This explains the higher selectivity observed with mordenites. In the more acidic beta zeolites the presence of copper ions on the walls of large channels initially favours side reactions, but also makes adsorbed ammonia more available for ammoxidation.

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SBA-15 functionalization with mercaptopropyltrimethoxysilane has been used to prepare supported gold catalysts for the low temperature CO oxidation reaction. Supports and catalysts have been characterized by chemical analysis, CHS analysis, XRD, TGA, nitrogen adsorption-desorption at 77 K, TEM, CPMAS NMR, XPS and EPR. Catalytic runs have been carried out at atmospheric pressure and 313-623 K and the influence of diverse thermal treatments of the samples prior to reaction has been investigated. The presence of organic residues and the size of the gold nanoparticles strongly affect catalytic activity. Only high-temperature calcination in air followed by treatment under H2 atmosphere leads to active catalysts. After complete elimination of the functionalizing agent, caused by the calcination step, a gold-mediated "activation" process of the silica support takes place during the hydrogen treatment. As a consequence, active catalysts for the low temperature CO oxidation are obtained, even though the size of the Au particles is too large for establishing direct Au-oxygen interactions, usually assumed to be essential for the reaction over silica-supported gold catalysts.