Comparative study of ZSM‐5 supported transition metal (Cu, Mn, Co, and Fe) nanocatalysts in the selective catalytic reduction of NO with NH3

Abstract

H‐ZSM‐5 was modified with transition metals (including Fe, Cu, Mn, and Co) by homogeneous deposition precipitation (HDP) method and tested as catalyst for the selective reduction of NO with ammonia (NH3‐SCR). The selectivity to N2 was higher than 95% in all the nanocatalysts and the NO conversion over nanocatalysts decreased in the following sequence Cu‐ZSM‐5 > Mn‐ZSM‐5 > Co‐ZSM‐5 > Fe‐ZSM‐5 at 200‐300°C. The Cu‐ZSM‐5 catalyst showed the highest catalytic activity, 95% of NO conversion at 300°C, among the catalysts investigated. The nature of the active sites was characterized by BET, TEM, H2‐TPR, and NH3‐TPD. Characterization results revealed that acidity and the redox properties of the catalysts play an important role in achieving high activity for NH3‐SCR reaction. The highest catalytic activity of Cu/ZSM‐5 can be correlated to easy reducibility of Cu species and strong acidic sites created by the Cu species. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 1049–1055, 2017