High-temperature reactions of triplet methylene and ketene with radicals

Journal Article · Thu May 08 04:00:00 EDT 1986 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100401a046· OSTI ID:5816902

Frank, P; Bhaskaran, K A; Just, T

The reactions of CH/sub 2/ and ketene with CH/sub 2/ and H have been investigated at elevated temperatures in the postshock region behind reflected shocks. Atomic (ARAS) and molecular resonance absorption spectrometry was used to record simultaneously H-atom and CO-molecule concentration profiles. The thermal decomposition of very low initial concentrations of ketene (2-50 ppm CH/sub 2/CO/Ar) served as a source for methylene. The experiments were conducted in the temperature range of 1650-2800 K at total densities of 5 x 10/sup -6/ to 1.3 x 10/sup -5/ mol cm/sup -3/. For temperatures above 2000 K the following rate coefficients (k in cm/sup 3/ mol/sup -1/ s/sup -1/) were deduced: CH/sub 2/ + CH/sub 2/ = C/sub 2/H/sub 2/ + 2H, k = (10 +/- 2) x 10/sup 13/; CH/sub 2/ + H = CH + H/sub 2/, k = (8 +/- 2) x 10/sup 12/. For temperatures between 1650 and 1850 K a value of (1.8 +/- 0.6) x 10/sup 13/ is deduced for the reaction of ketene with H atoms. 30 references, 9 figures, 1 table.

• Research Organization: DFVLR Institut fuer Physikalische Chemie der Verbrennung, Stuttgart, West Germany
• OSTI ID: 5816902
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 90:10; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
ABSORPTION
ABSORPTION SPECTROSCOPY
ACETYLENE
ALKYNES
ARRHENIUS EQUATION
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DATA
DECOMPOSITION
ELEMENTS
EQUATIONS
EXPERIMENTAL DATA
HYDROCARBONS
HYDROGEN
INFORMATION
KETENES
KINETICS
METHYLENE RADICALS
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PYROLYSIS
RADICALS
REACTION KINETICS
RESONANCE ABSORPTION
SHOCK TUBES
SHOCK WAVES
SPECTROSCOPY
THERMOCHEMICAL PROCESSES
THERMODYNAMICS
VERY HIGH TEMPERATURE