Abstract
Reactivity of monolith Cu-exchanged chabazite (Cu-CHA) catalyst was analyzed to investigate the reaction mechanisms of ammonia selective catalytic reduction (NH3-SCR). The reactions, namely Ammonia adsorption/desorption, NO reduction, NO2 reduction, and NH3 oxidation, were identified using monolithic H-CHA and Cu-CHA catalyst. A kinetic model for the steady-state NH3-SCR over monolithic Cu-CHA has been developed based on the experimental results. The adsorption heat of NH3 was measured by temperature programmed desorption (TPD). Arrhenius parameters for NO reduction and NH3 oxidation were also collected using a surrogate gas bench apparatus. The model predicted the catalyst efficiencies well in various conditions.
