Detailed Kinetic Models for SCR Over Cu-Zeolites

A detailed kinetic model was developed [11-13] and constructed out of several submodels previously described in this chapter. The different sites used in the model is discussed in Sect. 12.2.2. The submodels include (i) ammonia adsorp-tion/desorption, (ii) water adsorption/desorption, (iii) ammonia oxidation, (iv) NO2 storage, and (v) NO oxidation. The results of these smdies were used in developing 

In the presence of water, it is likely that HNO3 is formed on the snrface, which have been suggested for SCR over vanadia catalysts [41]. We have, therefore, added a reaction step to form HNO3 (Eq. 12.38). 

HNO3 can then react with ammonia on the surface to produce ammonium nitrate, which can decompose to produce N2O. In order to simpUly the model, these two steps in the model are described as one step  

Further, it is suggested that HNO2 is formed over vanadia, and then produces ammonium nitrite, which rapidly decomposes to produce water and N2 [41]. This mechanism was also used to derive the last step in the detailed model (Eq. 12.40) 

Grossale et al. [8] present a detailed kinetic model for ammonia SCR over Fe and Cu-zeolites, where the NO2 reactions are described by the following steps  

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