NH3-SCR activity, hydrothermal stability and poison resistance of a zirconium phosphate/Ce0.5Zr0.5O2 catalyst in simulated diesel exhaust

Abstract

A ZP/CZ (zirconium phosphate/Ce_0.5Zr_0.5O₂) catalyst exhibits over 80% NO_x conversion from 250 to 450 °C under a high GHSV of 300 000 h⁻¹ in the presence of H₂O, CO₂ and C₃H₈. Mixing with soot leads to a decrease in NO_x conversion of the catalyst at temperatures higher than 350 °C. After hydrothermal aging (760 °C for 48 h) and sulfur aging (400 °C for 48 h), ZP/CZ still possesses over 80% NO_x conversions in 289–450 °C and 297–466 °C respectively, which are significantly better than those of home made Cu-SAPO-34 and vanadium catalysts at higher temperatures. These results indicate that ZP/CZ is a promising catalyst for NO_x abatement for diesel engine exhausts.