Effects of NO2, CO,O2, and SO2 on oxidation kinetics of NO over Pt‐WO3/TiO2 catalyst for fast selective catalytic reduction process

The selective catalytic reduction rate of NO with N‐containing reducing agents can be enhanced considerably by converting a part of NO into NO₂. The enhanced reaction rate is more pronounced at lower temperatures by using an equimolar mixture of NO and NO₂. The kinetics of NO oxidation over Pt‐WO₃/TiO₂ catalyst has been determined in a fixed‐bed reactor with different concentrations of oxygen, nitric oxide, and nitrogen dioxide in the presence of 8% water. It has been found that the reaction is second order with respect to nitric oxide, first order for oxygen with a third‐order rate constant. Also, it is found that there is no effect on the reaction order with an addition of NO₂, CO, or SO₂. It follows the same second order but the reaction rate is found to be changed. It is observed that in the case of NO₂ and SO₂, the reaction rate tends to decrease, but it increases with the addition of CO into the feed. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 613–620, 2006