Last years nanosized gold particles attract much attention as a component of industrially perspective catalysts for some reactions as CO oxidation, NO reduction etc. We studied several systems including gold based on different synthetic zeolites pure or doped with another metals (Fe, Na). It was shown by different techniques (XPS, UV-Vis spectroscopy, TPR) that intrinsic properties of zeolites used and gold system preparation method influence significantly on the contribution of different gold species (ions, clusters and particles). For mixed Au-Me-zeolites activity level and dynamic of CO conversion with time in steam and temperature depends on nature of zeolite and specificity of Au-Me interaction. All binary metal systems were found to be activated in different degree during catalytic activity test due to mutual interaction of gold with second metal. Extremely high level of CO conversion and low dependence of activity on temperature was observed for Au- Fe- H- and Na-Y zeolites. The change in contribution of gold nanoparticles was observed after sample contact with CO.
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