Reactions of vinyl radicals at high temperatures: pyrolysis of vinyl bromide and vinyl iodide and the reaction H + C/sub 2/D/sub 2/. -->. D + C/sub 2/HD

Journal Article · Thu Nov 03 04:00:00 EST 1988 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100333a028· OSTI ID:6181470

Rao, V S; Skinner, G B

Five sets of experiments were carried out to determine the rate constant for dissociation of C/sub 2/H/sub 3/ at high temperatures. In all cases the measurements involved absorption of H or D Lyman-..cap alpha.. radiation in argon-diluted gas mixtures reacting behind shock waves. For pyrolysis of vinyl bromide at 0.5-atm total pressure was found for C/sub 2/H/sub 3/ + Ar ..-->.. C/sub 2/H/sub 2/ + H + Ar, k = 7.0 x 10/sup 13/ exp(-28 kcal/RT) mol/sup -1/ cm/sup 3/ s/sup -1/ at 1380-1750 K. For the same reaction initiated from vinyl iodide at 0.5-atm total pressure and 1060-1370 K, they found k = 3.5 x 10/sup 14/ exp(-33 kcal/RT) mol/sup -1/ cm/sup 3/ s/sup -1/. In three sets of experiments in which H atoms reacted with C/sub 2/D/sub 2/ to produce D atoms, they obtained values of kinfinity for the reaction H + C/sub 2/H/sub 2/ ..-->.. C/sub 2/H/sub 3/ of 8 x 10/sup 11/, 1.2 x 10/sup 12/, and 3.4 x 10/sup 12/ mol/sup -1/ cm/sup 3/s/sup -1/ in the temperature range 1200-1900 K, with no clearly visible temperature dependence. All of the experimental values lie 3-10 times lower than those deduced from earlier work at high temperatures or based on ab initio calculations for the vinyl radical.

• Research Organization: Wright State Univ., Dayton, OH (USA)
• DOE Contract Number: AC02-76ER02944
• OSTI ID: 6181470
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 92:22; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400800 -- Combustion
Pyrolysis
& High-Temperature Chemistry
ALKYL RADICALS
BROMINATED ALIPHATIC HYDROCARBONS
CHEMICAL REACTIONS
DATA
DECOMPOSITION
DEUTERIUM COMPOUNDS
DISSOCIATION
EXPERIMENTAL DATA
HALOGENATED ALIPHATIC HYDROCARBONS
HYDROGEN COMPOUNDS
INFORMATION
IODINATED ALIPHATIC HYDROCARBONS
NUMERICAL DATA
ORGANIC BROMINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
PYROLYSIS
RADICALS
THERMOCHEMICAL PROCESSES
VINYL RADICALS