Abstract: The present invention refers to a kind of deNOx catalyst without the reducing agent to decompose the NO, wherein it is to mix the Zeolite with Al2O3, then they were dried, calcined, and powdered to make the catalyst carrier, after adding the Pt/Rh or Pd/Rh noble metal solutions, again dry and calcine, then the deNOx catalyst without the usage of reducing agent such as ammonia, propane could be thus obtained, wherein its optimum conversion of stripping deNOx is within 250-500° C., besides, at the condition that there is CO except NO for that polluted air, the rate of stripping for the present invention could also achieves a fine results.

Abstract: A method for reducing nitrogen oxide with a catalyst and a system thereof comprises the following steps: (A) a step of guiding exhaust, selectively guiding the exhaust containing the nitrogen oxide into an oxygen removing reaction room based on the oxygen content of the exhaust. (If both the oxygen content and the temperature of the exhaust are in a required range, it is not necessary to use the oxygen removing reaction room); (B) a step of introducing the oxygen remover, introducing the oxygen remover into the oxygen removing reaction room from the storage vessel based on the consistency of oxygen in the exhaust. (If both the oxygen content and the temperature of the exhaust are in a required range, it is not necessary to introduce the oxygen remover); (C) a step of oxygen removing reaction, the oxygen remover generating an oxygen removing reaction in the reaction room to cause a function of oxygen removal; (d) a step of catalytic reaction, converting the oxygen removed exhaust a catalyst.