SO_x 함유 HC-SCR에서 산처리 Ag/Al_2O_3 촉매의 반응 특성

Abstract

Ethanol was used as reducing agent to remove NO_x exhaust from the stationary source. Pre-treatment with sulfuric acid over Ag/Al_2O_3 catalyst was dedicated to overcome the SO_2 poisoning effect. The NO_x reduction experiment was performed under the simulated condition of power plant The increased surface area with higher CPSI devoted to increase de-NO_x yield. De-NO_x yield of the NO_x exhaust containing 20 ppm of SO_2 increased after acid treatment with 0.7% H_2SO_4 over 4.0% Ag/Al_2O_3,where the increased dispersion of Ag found from the results of XRD and XPS was the dominant factor for the increased de-NO_x yield. However, the reason for the decreased de-NO_x yield with the acid treatment of higher concentration (1.0% and 2.0%) of H_2SO_4 was found to be due to the formation of Ag_2SO_4 crystallites found from XRD result. Acid-treated Ag/Al_2O_3 catalyst showed maximum de-NO_x yield at higher temperature than non-treated Ag/Al_2O_3 catalyst did.