Role of the alumina surface properties on the ammonia production during the NOx SCR with ethanol over Ag/Al2O3 catalysts

Fabien Can (1) , Aurelien Flura (1) , Xavier Courtois (1) , Sebastien Royer (1) , Gilbert Blanchard (2) , Patrice Marecot (1) , Daniel Duprez (1)

1 Catalyse par les métaux
2 Peugeot SA

The Selective Catalytic Reduction of NOx with ethanol (EtOH-SCR) was studied over Ag/Al2O3 catalysts. A special attention was given to the ammonia emission and its possible relationship with the support acidic properties. For this purpose, five aluminas were selected, three provided by manufacturers and two synthesized in our laboratory by sol-gel or precipitation route. The supports were impregnated with 2 wt.% Ag, and tested in EtOH-SCR. The results showed that the catalytic activity of Ag/Al2O3 greatly depends on the used alumina. An unexpected ammonia production is evidenced, varying between 6 and 27% at 450 degrees C, while NOx are fully converted. A correlation was established between the NH3 yield and the Lewis acid sites (LAS) density measured by pyridine adsorption for each catalyst

Mots clés: Ag/Al2O3; EtOH-SCR; ammonia; NH3 selectivity; alumina surface properties; infrared; LAS

Domaines: Catalyse

Fabien Can, Aurelien Flura, Xavier Courtois, Sebastien Royer, Gilbert Blanchard, et al.. Role of the alumina surface properties on the ammonia production during the NOx SCR with ethanol over Ag/Al2O3 catalysts. Catalysis Today, 2011, 164 (1), pp.474-479. ⟨10.1016/j.cattod.2010.10.036⟩. ⟨hal-00739548⟩