Catalytic reactions of NO over 0--7 mol% Ba/MgO catalysts. 1: The direct decomposition of NO

Journal Article · Mon Nov 15 04:00:00 EST 1999 · Journal of Catalysis

DOI:https://doi.org/10.1006/jcat.1999.2648· OSTI ID:20003847

Xie, S; Rosynek, M P; Lunsford, J H

A series of catalysts composed of barium oxide supported on magnesium oxide with Ba loadings up to 7 mol% has been studied for NO and N{sub 2}O decomposition. Nitrous oxide is an intermediate in the decomposition of nitric oxide; however, the rate of N{sub 2}O decomposition is much greater than that of NO decomposition so that the selectivity for N{sub 2} formation approaches 100% at T {gt} 700 C. Over 4 mol% Ba/MgO catalyst, the rate of N{sub 2} formation at 800 C was 0.22 {micro}mo/g s for a gas stream containing 1% NO in He. When the inhibiting effect of O{sub 2} is properly accounted for, the reaction order with respect to NO is two. This order is consistent with a mechanism in which gas-phase NO reacts with a surface NO{sub x} species that is probably present in an ionic form, considering the temperatures at which the reaction occurs. In situ Raman spectroscopy has demonstrated the presence of nitrate and nitrite ions on the surface, but the exact nature of the surface intermediate is not known.

• Research Organization: Texas A and M Univ., College Station, TX (US)
• OSTI ID: 20003847
• Journal Information: Journal of Catalysis, Journal Name: Journal of Catalysis Journal Issue: 1 Vol. 188; ISSN 0021-9517; ISSN JCTLA5
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
BARIUM OXIDES
CATALYTIC EFFECTS
CHEMICAL REACTION KINETICS
DECOMPOSITION
MAGNESIUM OXIDES
NITRIC OXIDE
NITROUS OXIDE