Selective reduction of NO with C3H6 under oxidizing atmosphere was studied over Cu-ion exchanged SAPO-n (n=5, 11, 34), β, USY, and ZSM-5. All examined Cu-ion exchanged catalyst exhibited the high activity for NO reduction with C3H6 and a large excess of 02, however, the temperature at the maximum NO conversion depends on the kind of molecular sieves. Although the maximum conversion of NO attained at a slightly higher temperature comparing with Cu-ZSM-5, Cu-SAPO-34 exhibited the highest activity for NO reduction among the examined catalysts. Furthermore, the high NO conversion was attained over a wide temperature range from 250 to 600° C. Thermal stability of SAPO-34 was extremely high and consequently, high activity to NO selective reduction on Cu-SAPO-34 was hardly decreased over 60 h at 400° C in an atmosphere containing 15 vol% H2O, and after thermal treatment at 800° C in humidified atmosphere, decreases in the activity for NO reduction was also small.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry