화학공학소재연구정보센터
Fuel, Vol.139, 232-239, 2015
The activity and mechanism study of Fe-Mn-Ce/gamma-Al2O3 catalyst for low temperature selective catalytic reduction of NO with NH3
Fe-Mn-Ce/gamma-Al2O3 granular catalyst was synthesized using the sol-gel method and then developed in the low temperature selective catalytic reduction (SCR) of NO with NH3. It achieved outstanding SCR activity at low temperature and also showed excellent space velocity tolerance and favorable SO2 and H2O resistance. The addition of Fe obviously increased the surface area and pore volume of the catalyst, and it also strengthened the surface acidity of Bronsted and Lewis acid sites, which was beneficial with the increase of SCR activity. The TPD and DRIFT results showed that the number of Lewis acid sites on the catalyst was much more than Bronsted sites, which could facilitate the formation of coordinated NH3 and - NH2 species. NO could be adsorbed in the form of unstable nitrates, which could then react with the adsorbed NH3 species directly. The most possible reaction pathway was proposed as that NH3 was firstly adsorbed on the catalyst after the competitive adsorption, and then the formed coordinated NH3 and - NH2 species reacted with the gas phase NO and generated N-2 and H2O. That is, the SCR reaction route mainly followed the Eley-Rideal mechanism. (C) 2014 Elsevier Ltd. All rights reserved.