Sulfur and Water Resistance and Activity of Ru-Ce-Zr-O x Catalysts for Nitric Oxide Catalytic Oxidation

Abstract

Most mobile pollution sources have narrow space. Due to its small occupation area, fast selective catalytic reduction (SCR) is more suitable for controlling oxynitride (NO x ) in exhausted gas in mobile pollution sources such as vessels. The fast SCR reaction can be divided into two stages: nitric oxide (NO) catalytic oxidation stage and NO x removal stage. This paper focused on the study of NO oxidation catalysts consists of ruthenium-cerium-zirconium (Ru-Ce-Zr) metal-oxides. It was found that the doping of ruthenium (Ru) which is the precious metal, greatly improved the catalytic activity. The NO oxidation rate of catalyst doped with 0.5% Ru at 300 °C was about 15% higher than that without Ru. However, with the increasing content of ruthenium, the sulfur and water resistance of catalysts decreased and the activity of the catalysts was only partially restored after regeneration. The results showed that Ru increased the activity of the catalysts while Ce and Zr improved the resistance of SO2 and H2O. Our work provided a solution to the space problem of mobile pollution sources such as vessels.