Method and catalyst for the purification of NOx-containing exhaust gases.

摘要

A method of purifying NOx-containing exhaust gases characterized by using ammonium acetate as a reducing agent to a zeolite-based catalyst. NOx in NOx-containing exhaust gases can be removed extremely effectively even at a low concentration thereof by using Fe-treated mordenite as a zeolite-based catalyst according to said method, and since it uses ammonium acetate as a reducing agent, an excellent effect free from ammonia slipping can be obtained. Particularly NOx in NOx-containing exhaust gases can be removed effectively at and around a discharge temperature of an exhaust gas from a gas engine in the presence of ammonium acetate as a reducing agent by constituting Fe-containing mordenite as a monolithic material. Hence, it makes it possible to obtain an excellent effect of simplifying the whole denitration system without needing temperature control of an exhaust gas and/or a catalyst bed. In addition, the NOx-purifying ability of the catalyst does not decrease over a long period of time. <IMAGE>