Mechanistic Study of the Influence of the Surface Acidity on Lean NO2 Reduction by Propane in HZSM-5
Journal article, 2005

This study focuses on the mechanism of lean NO x reduction by propane, over acidic zeolites (HZSM-5), and the influence of surface acidity. In situ FTIR measurements of ammonia adsorption indicate a higher number of Brønsted acid sites for a sample with a low SiO 2 /Al 2 O 3 ratio. The activity for NO x reduction and the selectivity for N 2 formation correlate well with the Brønsted acidity. Step-response experiments with NO 2 and propane show the formation of surface-bound NO + , isocyanate, unsaturated hydrocarbons, and amine species. Formation of the latter two seems to be closely related to the Brønsted acidity. In the NO 2 reaction with propane, the NO + species seem to play a vital role, probably reacting with carbenium ions (from propane cracking) to form isocyanates, which may be hydrolysed to amine species. Step-response experiments with isopropylamine and NO 2 indicate a fast reaction, where the amine and NO + species react over Brønsted acid sites. Hence, amine species are possible reaction intermediates in the lean reduction of NO 2 by saturated hydrocarbons, such as propane, over HZSM-5. © 2005 Elsevier Inc. All rights reserved.

no/c3h6/o-2 reaction

group metal-catalysts

oxygen excess

selective catalytic-reduction

in-situ ftir

steady-state

burn conditions

fe/zsm-5 catalysts

nitric-oxide

sulfur-dioxide

Author

Hanna Härelind Ingelsten

Competence Centre for Catalysis (KCK)

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Dongmei Zhao

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Competence Centre for Catalysis (KCK)

Anders Palmqvist

Competence Centre for Catalysis (KCK)

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Magnus Skoglundh

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Competence Centre for Catalysis (KCK)

Journal of Catalysis

0021-9517 (ISSN) 1090-2694 (eISSN)

Vol. 232 1 68-79

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Transport

Energy

Materials Science

Subject Categories

Physical Chemistry

Chemical Engineering

Chemical Sciences

DOI

10.1016/j.jcat.2005.02.022

More information

Latest update

11/5/2018