Cu-MOR, Cu-MFI, Co-MOR, Co-MFI and Mn-MFI were prepared by ion-exchange of Na-MOR or Na-MFI. On all samples, the catalytic activity for N2O decomposition, CH4 + N2O, CH4 + O-2, and for the selective catalytic reduction (SCR) of N2O in the presence of O-2 was studied in a flow apparatus with GC analysis of reactants and products. Extensively exchanged Cu-MOR and Cu-MFI were active for N2O decomposition. Cu-MOR and Cu-MFI exchanged at about 20% were much less active. All Co-MOR and Co-MFI catalysts, irrespective of the exchange-extent, were active for the same reaction. Mn-MFI was nearly inactive up to 773 K. All catalysts were active for CH4 + N2O. Cu-MOR and Cu-MFI were active for CH4 + O-2, whereas Co-MOR, Co-MFI and Mn-MFI were much less active for this reaction. Irrespective of the exchange extent, Cu-MOR, Cu-MFI, Co-MOR, and Co-MFI were active for the SCR of N2O with CH4. Conversely, Mn-MFI was not active for this reaction. Turnover frequency was slightly higher for the various reactions on Me-MFI (Me = Cu or Co) than for the corresponding reactions on Me-MOR. We conclude that on Cu- and Co-zeolites, the SCR of N2O with CH4 consists of two nearly independent reactions: CH4 + N2O prevails at high temperature (673-773 K), and CH4 + O-2 at lower temperature. The two reactions involve different catalytically active oxygen species: CH4 + O-2 involves a molecular form, and CH4 + N2O a monoatomic form, arising from N2O. Because Co-MOR and Co-MFI are also active for the SCR of NO, we suggest that these materials are promising catalysts for the simultaneous SCR of N2O and NO with CH4. (C) 2011 Elsevier B.V. All rights reserved.