The influence of surface acidity on NO2 reduction by propane under lean conditions
Journal article, 2004

This investigation focuses on the influence of surface acidity on the continuous catalytic reduction of NOx by propane under lean conditions. The acidity was varied by studying noble metal free alumina, silica and co-precipitated aluminium-silicates with varying alumina-silica ratio. The catalysts were characterised by isopropylamine temperature programmed desorption (TPD), with respect to NOx reduction (NO2 and propane) and by Fourier Transform Infrared (FTIR) spectroscopy. The isopropylamine TPD was used to determine the sample acidity. The amount of Bronsted acid sites increased with increasing amount of alumina. The sample activity for NOx reduction with propane was found to correlate with the Bronsted-site density. Furthermore, no N2O was formed during the activity studies. The FTIR measurements implied formation of isocyanate species on the surface of the catalyst sample when NO/NO2, propane and oxygen were present in the gas phase. FTIR data also reveal an increasing amount of adsorbates on the surface with increasing amount of alumina in the sample. Moreover, with propane present, NO-species were consumed to a higher extent over samples containing a larger amount of alumina. Our results suggest a connection between the Bronsted-site density and the NOx reduction with propane under lean conditions.

aluminum-silicate

surface acidity

lean NOx reduction

propane

FTIR

Author

Hanna Härelind Ingelsten

Competence Centre for Catalysis (KCK)

Chalmers, Department of Chemistry and Bioscience

Åsa Hildesson

Chalmers, Applied Physics, Chemical Physics

Competence Centre for Catalysis (KCK)

Erik Fridell

Competence Centre for Catalysis (KCK)

Chalmers, Applied Physics, Chemical Physics

Magnus Skoglundh

Competence Centre for Catalysis (KCK)

Chalmers, Department of Materials and Surface Chemistry, Applied Surface Chemistry

Journal of Molecular Catalysis A: Chemical

1381-1169 (ISSN)

Vol. 209 1-2 199-207

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Transport

Energy

Materials Science

Subject Categories

Physical Sciences

Chemical Engineering

DOI

10.1016/j.molcata.2003.08.016

More information

Latest update

11/5/2018