A kinetic study of oxygen adsorption/desorption and NO oxidation over Pt/Al2O3 catalysts
Journal article, 1999

Laboratory tests and kinetic modeling were carried out in order to provide kinetic input data to a systematic investigation of the mechanism of nitrogen oxides (NO,) storage in catalysts used for lean-burn engines. In particular, we present a kinetic model of the NO oxidation to NO2 over a Pt/Al2O3 model catalyst for the temperature range 250-450 degrees C. Since the oxygen behavior at atmospheric pressure is critical for such a model, we have also studied the adsorption/desorption of oxygen by temperature-programmed desorption (TPD) experiments. The experiments show that oxygen starts to desorb at about 300 degrees C. Furthermore, the NO oxidation was studied in a temperature ramp with NO and oxygen in the gas feed. The data from this experiment and the above-determined values for the oxygen adsorption/desorption were used to construct a kinetic model for the NO oxidation. Finally, the model was validated with some transient experiments with either NO or NO2 and different oxygen concentrations in the gas feed. We found a good agreement between these experiments and the model.

REDUCTION

LEAN-BURN CONDITIONS

ADSORPTION

DISPERSION

HIGH COVERAGES

SURFACE

PT(111)

ATOMIC OXYGEN

DESORPTION

ALUMINA

Author

Louise Olsson

Competence Centre for Catalysis (KCK)

Department of Chemical Reaction Engineering

Björn Westerberg

Department of Chemical Reaction Engineering

Competence Centre for Catalysis (KCK)

Hans Persson

Competence Centre for Catalysis (KCK)

Chalmers, Applied Physics

Erik Fridell

Competence Centre for Catalysis (KCK)

Chalmers, Applied Physics, Chemical Physics

Magnus Skoglundh

Department of Applied Surface Chemistry

Competence Centre for Catalysis (KCK)

Bengt Andersson

Department of Chemical Reaction Engineering

Competence Centre for Catalysis (KCK)

Journal of Physical Chemistry B Materials

1089-5647 (ISSN)

Vol. 103 47 10433-10439

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Transport

Energy

Materials Science

Subject Categories

Chemical Engineering

DOI

10.1021/jp9918757

More information

Created

10/7/2017