Promoting effects of Na and Fe impurities on the catalytic activity of CaO in the reduction of NO by CO and H-2
Journal article, 1998

The heterogeneous reduction of NO by H-2 and CO over different CaO materials is investigated. The dependence of the specific NO reduction rate on the impurity content is demonstrated for both reducing species. The roles of two specific impurities, i.e., Na and Fe, as well as their combined effect are investigated. The apparent activation energies for the NO + CO and NO + Hz reactions are determined for three different calcium oxides. Values between 26 and 28 kcal/mol are obtained. The influence of impurity content is found in the preexponential factor of the Arrhenius equation. A reaction mechanism based on a rate-determining surface-oxygen-abstraction step is suggested. This mechanistic understanding is explored to compare the activities of other alkaline-earth oxides. Particularly, a linear correlation between the apparent activation energy and the lattice parameter is observed.

Author

Filip Acke

Itai Panas

Chalmers, Department of Environmental Inorganic Chemistry

Journal of Physical Chemistry B Materials

1089-5647 (ISSN)

Vol. 102 26 5127-5134

Subject Categories

Physical Chemistry

More information

Created

10/7/2017