Effects of hydrogen and oxygenated hydrocarbons on the activity and SO2-tolerance of Ag/Al2O3 for selective reduction of NO

De-NOx performance and SO2-tolerance of Ag/Al2O3 catalyst for selective catalytic reduction of NO by hydrocarbon (HC-SCR) and HC-SCR in the presence of H-2 (H-2-HC-SCR) were investigated using 10 types of reductant (Et2O, ETBE, EtOH, 1-propanol, 2-propanol, t-butanol, 1-propanal, ethyl acetate, acetone, C3H8). Among various reductant tested, Et2O was most effective for achieving high de-NOx activity for HC-SCR and H-2-HC-SCR. For all the reductants, de-NOx activity at low temperature region was increased by H-2 co-feeding. Degree of activity enhancement was higher for C3H8 than for oxygenates, which is consistent with our previous proposal that H-2 enhances de-NOx activity by promoting the oxidative activation of alkane into partially oxidized hydrocarbon intermediates. Effects of reductants and H-2 co-feeding on the SO2-tolerance were examined using Et2O, ETBE, and EtOH. The result showed that use of oxygenates as well as H-2 co-feeding resulted in the higher SO2-tolerance. (c) 2006 Elsevier B.V. All rights reserved.