程序升温脱附研究CoH-FBZ上NOx的吸附

Selective catalytic reduction of NO by methane in the presence of excess oxygen over CoH-FBZ zeolite composite catalyst has an advantage over the physical mixture of CoH-Y and CoH-Beta. The interaction between NO or NO+O2 and the catalyst revealed by adsorption and temperatureprogrammed desorption (TPD) technique, results directly in the effect of the topological structure of supports upon the stability of N-and O-species on the surface of the catalysts. The NO+O2-TPD profile of the CoH-FBZ catalyst exhibits two NO2 desorption peaks at 630K and 660K, respectively. This indicates that new adsorption centers for-NOy are formed over the CoH-FBZ and adsorbed more stably on CoH-FBZ than on CoH-Y or CoH-Beta, NO does in a similar manner. The synergism of the newly formed Co sites and the new strong acidic sites contributes to the novel CH4-SCR catalytic properties of the CoH-FBZ catalysts.