Catalyst Types and Kinetics

Most of the work reviewed in this section is related to the selective reduction of NO over various catalyst types and using a variety of reductants. 

Many catalyst compositions are in use or under study for the SCR reaction [4]. Vanadia-type catalysts show high activities for the reduction of NO with NH3. For zeolites CO, H2, or hydrocarbons are used as the reductant. 

Supported vanadia catalysts and physical mixtures of V2O5 and Ti02 are described, regarding mechanisms and kinetics. Kinetic data for a variety of supported vanadia catalysts are given in Table 4 [28]. Catalysts with Ti02 as support have the highest activity. 

Ozkan et al. [47] studied the morphological aspects of unsupported vanadia catalysts. Two types of vanadia were prepared. The preparation procedures described above resulted in thick particles (V20s(a)) and thin, sheet-like particles (decomposition of ammonium metavanadate V20s(d)). V20s(a) contains relatively more 

The role of ammonia oxidation was studied more comprehensively [36]. From the experimental results it was suggested that ammonia adsorption takes place at two types of sites located on the (010) and (100) planes. V-O-V groups were found to 

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