(y = 12, 25 and 45). The activity of the catalysts was evaluated in the reduction of NO to N 2 in an oxidative atmosphere using propane or methane as reducing agents. The Cu catalysts were only active with propane and they presented higher activity than the Co-based catalysts, the latter being active with both hydrocarbons. H 2 -TPR and DRS-UV/Vis data allowed correlation between the activity towards NO reduction and the presence of cationic charge-compensating species in the zeolite. It was also verified that the hydrocarbons are preferentially oxidised by O 2 , a reaction that occurs simultaneously with their oxidation with NO.