Experimental Study of the NO Oxidation to NO2 Over Metal Promoted Zeolites Aimed at the Identification of the Standard SCR Rate Determining Step

Steady state and transient kinetic runs devoted to the comparative analysis of NO oxidation and standard SCR reactions over commercial Cu- and Fe-promoted zeolite catalysts are herein presented with the aim to clarify whether NO oxidation to NO₂ is the rate determining step (rds) of the standard SCR reaction. It is found that this statement seems questionable in the light both of the herein collected experimental results and of scattered evidence from the literature.