Ag/Al2O3 촉매하의 HC-SCR에서 수소 풍부 에탄올의 반응 특성

Abstract

Ethanol was used as reductant to remove NOx over Ag/Al2O3 catalyst via SCR from stationary emission source. Among the tested hydrocarbon reductants, ethanol showed highest de-NOx performance over the Ag/Al2O3 catalyst. De-NOx efficiency of about 83% was obtained in the condition of GHSV 20,000 hr-1, NOx 200 ppm, CO 200 ppm, O2 13%, H2O 5% and mole ratio of ethanol/NOx = 2 between temperature of 300℃ and 400℃. While SO2 presence in the NOx exhaust suppressed the catalytic activity, catalyst with acid (0.7% H2SO4) treatment of catalyst showed higher catalytic activity, where In-Situ DRIFT showed S presence over catalyst surface was increased after acid treatment of catalyst. From in-situ DRIFT and SCR results, it was concluded that sulfur presence over the surface of Ag/Al2O3 catalyst was the dominant factor to control the de-NOx reaction yield via HC-SCR from the exhausted gas including SO2.