Catalytic performance and steady-state kinetics of Cu-ZSM-5 for selective catalytic reduction of NO with NH 3

Abstract

A series of Cu-ZSM-5 catalysts with different Cu loadings were prepared by an incipient wetness impregnation method. These catalysts were used for studies of selective catalytic reduction (SCR) of NO by NH 3. The results showed that Cu-ZSM-5 with 5% Cu loading showed the best catalytic activity, the conversion of NO was more than 80% over the temperature range 198-470 °C, and the highest NO conversion was 96.5%. The SCR activity was only influenced slightly by the addition of H 2O or SO 2. Visible diffraction of the CuO phase was observed when the Cu content was above 5%. The results of steady-state kinetics studies indicated that the SCR reaction over Cu-ZSM-5 with 5% Cu loading was zero-order with respect to NH 3, first-order with respect to NO, and nearly half-order with respect to O 2. The apparent activation energy for the reaction was found to be 47.7 kJ·mol -1. © Editorial office of Acta Physico-Chimica Sinica.