Cu-ZSM-11 molecular sieve was prepared by the microwave ion-exchange method. The heating behavior of several kinds of metal oxides under microwave irradiation was investigated. Some metal oxide(MnO2 >CuO >Ni2O3)which is of good absorption property for microwave was selected to be used for mixing with Cu-ZSM-11 catalyst to prepare the microwave catalysts. Direct decomposition of NO over the microwave catalyst MeOx/Cu-ZSM-11 was conducted with microwave irradiation

and their performance was investigated under microwave irradiation and traditional heating modes respectively. The results show that the conversion rate of decomposing NO is significantly higher under microwave irradiation than under traditional heating; and at catalyst bed temperature 350℃

the NO conversion is achieved up to 99.30% and N2 selectivity 99.9%. Furthermore

under microwave irradiation

the conversion of decomposing NO is higher for the mixture catalyst MeOx/Cu-ZSM-11 than for alone metal oxides and alone Cu-ZSM-11

indicating that microwave irradiation plays important role in catalytic decomposition of nitrogen oxide. The results indicate also that over MeOx/Cu-ZSM-11 with microwave irradiation

oxygen concentration in steam has almost no influences on its catalytic activity for NO decomposition

i.e. microwave irradiation can remove oxygen inhibition in decomposition reaction and keep unique selective effect. Similarly

the influence of water vapor in stream is also much less under microwave irradiation. The exit gas temperature is almost not change for Microwave-assisted reaction

and is the same as the reaction temperature 500-600℃ for conventional heating mode reaction.