A shock tube study of reactions of C atoms and CH with NO including product channel measurements

Journal Article · Thu Apr 18 04:00:00 EDT 1991 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100161a042· OSTI ID:5636411

Dean, A J; Hanson, R K; Bowman, C T ^[1]

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1. Stanford Univ., CA (United States)

The reactions of C atoms and CH with NO, which are believed to be initial steps in the NO reburning reaction mechanism, were studied at high temperature behind reflected shock waves. C atoms were formed by pyrolysis or photolysis of dilute mixtures of C{sub 3}O{sub 2} in argon or by pyrolysis of dilute mixtures of CH{sub 4} in argon. CH was formed from the pyrolysis of dilute mixtures of CH{sub 4} or C{sub 2}H{sub 6} (<30 ppm) in argon. C atoms were detected by use of atomic resonance absorption (ARAS) at 156.1 nm. CH was detected by CW, narrow-line-width laser absorption at 431.131 nm. In the presence of excess NO, C atoms formed by pyrolysis or photolysis rapidly were removed by C({sup 3}P) + NO {yields} products (1). A first-order kinetic analysis led to a rate coefficient K{sub 1} = 4.8 {times} 10{sup 13} ({plus minus}45%) cm{sup 3} mol{sup {minus}1}s{sup {minus}1} over the temperature range 1550-4050 K and pressure range 0.5-1 atm. In order to determine the rate coefficient of CH(X{sup 2}{Pi}) + NO {yields} products (2), a perturbation technique was employed. In this technique, the CH concentration profile resulting from pyrolysis of CH{sub 4} or C{sub 2}H{sub 6} diluted in argon was perturbed by the addition of NO. A detailed analysis of the CH profiles led to the rate coefficient k{sub 2} = 1.0 {times} 10{sup 14} ({plus minus}50%) cm{sup 3} mol{sup {minus}1}s{sup {minus}1} over the temperature range 2570-3790 K and pressure range 0.6-1.1 atm.

• OSTI ID: 5636411
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 95:8; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical &amp; Physicochemical Properties
54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring &amp; Transport-- (1990-)
ABSORPTION SPECTROSCOPY
ALKANES
BRANCHING RATIO
CARBON
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DATA
DECOMPOSITION
ELEMENTS
ENERGY LEVELS
EXPERIMENTAL DATA
HYDROCARBONS
INFORMATION
KINETICS
LOW PRESSURE
MATHEMATICAL MODELS
MEDIUM PRESSURE
NITRIC OXIDE
NITROGEN COMPOUNDS
NITROGEN OXIDES
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PRESSURE DEPENDENCE
PYROLYSIS
REACTION KINETICS
SAMPLE PREPARATION
SHOCK TUBES
SHOCK WAVES
SPECTROSCOPY
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE
TEMPERATURE RANGE 1000-4000 K
TEMPERATURE RANGE OVER 4000 K
THEORETICAL DATA
THERMOCHEMICAL PROCESSES