Catalytic combustion of volatile organic compounds on gold/titanium oxynitride catalysts

Catalytic oxidation of n-hexane, benzene and 2-propanol was investigated on Au/TiOxNy and Au/TiO2 catalysts prepared by the deposition-precipitation method and characterized by XRD, TEM and XPS techniques. The dispersion and average size of the gold particles are dependent on the nitrogen content of the support. Calcination of samples leads to a decrease in the nitrogen content of the samples and to gold particle agglomeration. In gold catalysts with high nitrogen content, XPS detects the existence of partially oxidised Auδ+ species. The presence of Auδ+ or Au0 species and the amount and size of gold particles determine the activity towards the catalytic combustion of VOCs of these systems.