NO reduction by CO over gold catalysts supported on Fe-loaded ceria

Abstract Nanosized gold catalysts on Fe-loaded ceria were studied in NO reduction by CO in the presence of H 2 and water. The Fe-modified ceria supports (5, 10 and 20 wt% Fe 2 O 3 ) were synthesized by two different methods: mechanochemical mixing (MM) and impregnation (IM) methods. Gold (3 wt%) was loaded by deposition-precipitation method. The samples was characterized by XRD and H 2 -TPR measurements; Mossbauer spectroscopy results of fresh and used catalysts were used for clarifying the role of Fe addition. It was established that the presence of very small gold particles was not of crucial importance. The Fe-modification of ceria was beneficial for NO conversion, however it decreased the selectivity to N 2 by increasing the selectivity to N 2 O. The 100% selectivity to N 2 at 250 °C as well as a high catalytic activity and stability was observed over gold catalyst on ceria support containing 5 wt% Fe 2 O 3 and prepared by IM method.