Specifics of the desorption of oxygen from a silver surface promoted by phosphates

The interaction of oxygen with the surface of a polycrystalline silver catalyst promoted with phosphorus-containing compounds was studied by the temperature-programmed desorption method. It was demonstrated that the introduction of a phosphorus-containing promoter gives rise to the formation of predominantly high-temperature forms of oxygen, which are more strongly bonded to the catalyst surface. The chemical composition of the active silver surface at various stages of its evolution was determined by IR spectroscopy. Under the action of temperature and a reducer, the polyphosphate promoter layer was observed to produce metal silver particles, which participate in the formation of active sites at the catalyst surface.