Micro-structured Cu-ZSM-5 catalyst on aluminum microfibers for selective catalytic reduction of NO by ammonia.

[Display omitted] • Microfibrous-structured Cu-ZSM-5/Al-fiber catalysts with different Si/Al molar ratios were synthesized for SCR reaction. • Adsorbed bridged nitrates species is in accordance with the enhanced NO degradation activity. • Microstructured Cu-ZSM-5 catalysts are more active at high-throughout conditions due to the enhanced mass transfer. Selective catalytic reduction of NO x with NH 3 (NH 3 -SCR) is one of the most efficient technologies to remove NO x emissions. The copper ion-exchanged zeolites with broad temperature windows and high N 2 selectivity are very promising for this process. In this work, we synthesized a series of microfibrous-structured Cu-ZSM-5/Al-fiber catalysts for SCR reaction by changing the Si/Al molar ratios. The in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of NH 3 adsorption results show that the Cu-ZSM-5/Al-fiber catalysts with higher Si/Al molar ratios have higher NH 3 adsorption capacity. The subsequent NO adsorption results show that the amount of adsorbed bridged nitrates species is in accordance with the enhanced NO x degradation activity. At moderate temperature, Cu-ZSM-5/Al-fiber catalyst shows better NH 3 -SCR performance under higher gas hourly space velocity (GHSV), indicating microstructured Cu-ZSM-5 catalysts are more active at high-throughout conditions due to the enhanced mass transfer. [ABSTRACT FROM AUTHOR]