H2-SCR 촉매의 NOx와 CO 저감 성능에 관한 ZrO2와 La의 영향

Abstract

This study is to improve the reduction performance of NOx and CO harmful gases and to investigate effect of ZrO₂ and La on the NOx and CO reduction performance of H₂-SCR catalyst. A model gas reactor was used, and catalyst temperature was tested in a steady state. The 0.5Pt-2CeO₂-2ZrO₂/TiO₂ catalyst had high de-NOx performance and showed a wide window distribution in the temperature range from 125℃ to 255℃. When an appropriate amount of ZrO₂ was supported, the de-NOx performance was improved by preventing oxidation at medium temperature of the reducing agent, H₂. It became active from the catalyst with a small amount of La supported, and the de-NOx performance was improved in the temperature range from 175℃ to 200℃. In the H₂-SCR catalyst to which the additive catalysts (ZrO₂, La) were added, the reaction rate was lowered, and the temperature of the gas discharged from the internal combustion engine must be considered. Since a large amount of coating may lower the catalyst dispersion of noble metals pt, the optimal coating amount should be studied in consideration of catalyst cost and performance.