Insight into the hydrothermal and chemical stability of Cu-LTA zeolites for NOx abatement by NH3-SCR

Cu-CHA zeolite is the state-of-the-art commercial catalysts for NH3-SCR, showing excellent low temperature activity and selectivity coupled to good hydrothermal stability, but it suffers from SO2 poisoning. Starting from the knowledge acquired on this catalyst, we aim to study Cu/LTA zeolites, which have been shown to have even better hydrothermal stability. High Si/Al ratio Cu/LTA, fresh and aged at high temperature (750 and 900 °C), will be characterized by operando XAS during thermal activation (including wet conditions for the fresh ones), followed by exposure to NH3-SCR reactants, to get information on Cu speciation in different temperature and reactants conditions, NH3-SCR reaction mechanism and effect of SO2 poisoning