Abstract: The decomposition of NO in a continuous microwave discharge was investigated.When(NO,He) mixture was used as the reactant, almost all NOcan be converted to N₂.In(NO, O₂ ) He) system,the conversion of NO was nearly 80%, and the selectivity of N₂ was 80%.When adding 5% H₂O to(NO,O₂, He) system, the productivity of N₂ was not changed basically.However, as the microwave power wasincreased, the conversion of NO increased, and the selectivity of N₂ increased even more.The effects ofNOand O₂ concentrations, and flow-rate on NO removal were also observed in the microwave discharge.

Key words: Microwave discharge, NO removal, Selectivity of N₂, Microwave power