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Selective Catalytic Reduction of NOx by Propane in Oxidizing Atmosphere on Catalysts Based on Metals in Zeolite Matrices
Schwarze, Michael ; Sobalík, Zdeněk (advisor) ; Nižňanský, Daniel (referee) ; Dědeček, Jiří (referee)
5. CONCLUSIONS A set of spectroscopic techniques (electron spin resonance, infrared spectroscopy and Móssbauer spectroscopy) usď under conditions near to in-siÍu experiments provided for the frrst complex identification of individual řon species present in a group of pentasil zeolites, i.e. FER, BEA, and MFI' Identifiď structural parameters of individual iron sites and their redox properties in various types of zeolites provide9ttr::S1qilthe relationship between structure and catalyic performance of such materials for selective catalýic reduction of No* by propane in the presence ofoxygen. It has been shown that, while the individual types of Fe-zeolites differ in structural conditions for the individual processes controlling the final SCR perforrnance, in the temperature range 200 - 250.C these individual effects are effectively compensatď. on the other hand, Fe-BEA displays the best combination of structural features for supporting the reaction in the temperature range between 300 and 350.C. The catalýic activity above 350oC is then dominated by a catalyst ability to suppress the nonselective oxidation of propane, connectď to lower efficiency in targeting the řon cationic positions during catalyst preparation. Nevertheless, all three zeolites used provide structural conditions for preparation of highly...
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