NH3-SCR Activity Characterization of Fully Formulated Chabazite Catalysts: Cu-SSZ-13 versus Cu-SAPO-34

Catalytic performance differences in NOx reduction, NH₃ oxidation, NH₃ storage, and O₂ level influences have been observed between the two formulations which can be related to the zeolite composition, acidity, copper species, and resultant impact on reactant adsorption and desorption characteristics.  Attempts are made to explain differences due to physicochemical properties.