SO2 promotion in NH3-SCR reaction over V2O5/SiC catalyst at low temperature

Abstract Silicon carbide (SiC) supported vanadium catalysts were obtained using the wet chemical impregnation method, and their removal of NOx with the presence of SO 2 at low temperature was evaluated. The effect of carbon was observed by comparing different carbon-based catalysts. V 2 O 5 /SiC (1 wt.%) catalyst had a NOx removal efficiency of 86% in the presence of SO 2 at 250 °C with a GHSV of 180,000 h −1 . In this study, the temperature-programmed desorption of NH 3 (NH 3 -TPD) and temperature-programmed decomposition (TPDC) of NH 4 HSO 4 deposited on the catalysts and reaction were performed to determine the influence of carbon on the performance of a carbon-based catalyst in the presence of SO 2 . The NO on the carbon support can effectively react with the NH 4 HSO 4 formed on the catalyst surface at low temperatures. Additionally, the adsorption of NH 3 was higher on carbon-based catalysts that were pre-adsorbed with SO 2  + O 2 . Thus, SO 2 promotes the activity of a carbon-based catalyst at low temperatures, and carbon has very important effect on the promotion of that activity.