N2O decomposition and reduction on Co-MOR, Fe-MOR and Ni-MOR catalysts: in situ UV–vis DRS and operando FTIR investigation. An insight on the reaction pathways
Co-, Fe- or Ni-exchanged Na-MOR (Si/Al = 9.2) were prepared by ion-exchange method. The catalytic activity for N2O decomposition in the absence or in the presence of NO and for N2O reduction with CH4 in the absence of O2 (CRN2O), or in the presence of O2 (SCRN2O) was investigated. The catalytic measurements were performed in a flow apparatus with GC analysis of reactants and products. On Fe-MOR, in situ FTIR and UV–vis characterization evidenced coordinatively unsaturated sites (c.u.s.) Fe2+ arising from two families of Fe3+ dimers with different reducibility.