Abstract

In order to adjust the redox properties of perovskite-based silver catalysts to satisfy the requirements for their application under overstoichiometric oxygen conditions (lean burn), three mixtures were prepared [Mixture (I): 10% La0.88Ag0.12FeO₃ + 90% Al₂O₃; Mixture (II): 3% Ag/(10% La0.88Ag0.12FeO₃ + 90% Al₂O₃); Mixture (III): 10% La0.88Ag0.12FeO₃ + 90% (3%Ag/Al₂O₃)]. Mixture (I) with only a 10% La0.88Ag0.12FeO₃ blend exhibited a NO reduction behavior similar to that of La0.88Ag0.12FeO₃ alone at stoichiometric oxygen (1% O₂). NO conversion of La0.88Ag0.12FeO₃ under an excess of oxygen (10% O₂) was however significantly improved by mixing with Al₂O₃ resulting in a value of ~ 30% at >400 °C in the case of Mixture (I). Ag impregnation facilitated the NO catalytic reduction, leading to a better deNOx performance for Mixture (II) and Mixture (III) than that of Mixture (I). It was also found that those silver atoms associated with Al₂O₃ are more effective for NO transformation. Therefore, the optimal mixed catalyst was Mixture (III), which shows satisfactory NO reduction and C₃H₆ oxidation at 500 °C under the whole range of O₂ content from 1% to 10%.

Recommended Citation

Zhang, Runduo; Alamdari, Houshang; Bassir, Mahbod; and Kaliaguine, Serge (2007) "Optimization of Mixed Ag Catalysts for Catalytic Conversions of NO and C₃H₆," International Journal of Chemical Reactor Engineering: Vol. 5: A70.
Available at: http://www.bepress.com/ijcre/vol5/A70