Ethanol-selective catalytic reduction of NO by Ag/Al2O3 catalysts: Activity and deactivation by alkali salts

Leonhard Schill, Siva Sankar Reddy Putluru, Casper Funk Jacobsen, Christian Houmann Hansen, Rasmus Fehrmann, Anker Degn Jensen

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Ag/Al2O3 catalysts with and without potassium doping were prepared by incipient wetness impregnation and characterized by N2 physisorption, XRPD, NH3-TPD and SEM. The influence of the Ag content from 1 to 5 wt.% was investigated for the selective catalytic reduction (SCR) of NO with ethanol. The 3 wt.% Ag/Al2O3 catalyst was found to be the most active and CO2 selective over a wide temperature window (300–500 ◦C). Addition of 500 ppm of H2 has a mild promotional effect on the activity while SO2 has a strong negative influence on the SCR activity. Furthermore, the Ag/Al2O3 ethanol-SCR catalyst deactivated significantly by the addition of potassium although it was more resistant than the conventional V2O5 based NH3-SCR catalyst, which deactivated more at lower potassium loading. The higher potassium resistivity of the Ag/Al2O3 catalysts seems to be due to differences in reaction mechanism of Ag/Al2O3 ethanol-SCR catalyst compared to the conventional NH3-SCR catalyst. The still low potassium resistance, in combination with the high sensitivity to SO2, seems not to make these catalysts a real option for biomass fired boilers.
Original languageEnglish
JournalApplied Catalysis B: Environmental
Volume127
Pages (from-to)323-329
ISSN0926-3373
DOIs
Publication statusPublished - 2012

Keywords

  • SCR of NO with ethanol
  • Ag/Al2O3
  • Potassium poisining

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