KINETIC MODELING OF NITRIC-OXIDE REDUCTION OVER A HIGH-SURFACE AREA V2O5-TIO2 CATALYST

Selective nitric oxide reduction over a high-surface area V2O5-TiO2 Catalyst was studied in the range 200-350-degrees-C, at different initial NH3/NO ratios and contact times, in the presence of excess oxygen. The experimental conversion-time data were compared with different kinetic models developed on the basis of information from the literature. In the temperature range examined, the results are consistent with a reaction mechanism involving the formation of a relatively stable nitrosamidic intermediate. At the highest temperatures, this reaction mechanism can degenerate into an Eley-Rideal mechanism. At T > 250-degrees-C, the inhibiting effect of water on the overall reaction rate was also quantitatively explained in terms of competitive adsorption on the active sites.