Reaction of acetaldehyde and acetyl radical with atomic and molecular oxygen

Journal Article · Thu Jul 27 00:00:00 EDT 1989 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100352a032· OSTI ID:6985877

Miyoshi, Akira; Matsui, Hiroyuki ^[1]; Washida, Nobuaki ^[2]

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1. Univ. of Tokyo (Japan)
2. National Institute for Environmental Studies, Ibaraki (Japan)

The reaction of acetaldehyde with atomic oxygen, O({sup 3}P), was studied by the discharge-flow-photoionization mass spectrometry method at room temperature (295 {plus minus} 4K) for the conditions of excess atomic oxygen. The rate constant for reaction 1, CH{sub 3}CHO + O {yields} CH{sub 3}CO + OH, was (3.9 {plus minus} 0.3) {times} 10{sup {minus}13} cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. Branching fractions for the subsequent reactions 2a, CH{sub 3}CO + O {yields} CH{sub 2}CO + OH, and 2b, CH{sub 3}CO + O {yields} CH{sub 3} + CO{sub 2}, were determined to be 22 {plus minus} 5% and 76 {plus minus} 24%, respectively. The experiments in the presence of molecular oxygen show that the ratio of rate constants for reaction 3, CH{sub 3}CO + O{sub 2} + M {yields} CH{sub 3} CO{sub 3} + M, to reaction 2 is (6.3 {plus minus} 0.5) {times} 10{sup {minus}3} (total pressure 3.6 Torr (He)). From the rate constant for reaction 3 obtained by McDade et al., the rate constant for reaction 2 was calculated: k{sub 2} = (3.2 {plus minus} 0.7) {times} 10{sup {minus}10} cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. When the concentration of molecular oxygen increased, the yields of both CH{sub 3} and CH{sub 2}CO decreased. From this decrease, the branching fractions for reactions 4a, CH{sub 3}CO{sub 3} + O {yields} CH{sub 2}CO + OH + O{sub 2}, and 4b, CH{sub 3}CO{sub 3} + O {yields} CH{sub 3} + CO{sub 2} + O{sub 2}, were determined: <10% and 27 {plus minus} 25%, respectively. A discussion of the other products from CH{sub 3}CO{sub 3} + O is presented.

• OSTI ID: 6985877
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 93:15; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400000* -- Chemistry
400800 -- Combustion
Pyrolysis
&amp; High-Temperature Chemistry
54 ENVIRONMENTAL SCIENCES
540110
ACETALDEHYDE
ACETYL RADICALS
ACYL RADICALS
ALDEHYDES
ATMOSPHERIC CHEMISTRY
CHEMICAL REACTIONS
CHEMISTRY
COMBUSTION PRODUCTS
DATA
DATA ANALYSIS
ELEMENTS
EXPERIMENTAL DATA
INFORMATION
MEASURING INSTRUMENTS
MEASURING METHODS
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
OXYGEN
RADICALS