Kinetics and Mechanism of the Reaction of OH with C6H6 over 790-1410 K

Article abstract of DOI:10.1021/j100262a026

The AeroChem high temperature photochemistry (HTP) techniqur was used to study reaction OH + C6H6 <*> products (1).Direct measuremnts of qverall rate coefficient k₁(T) for this reaction were obtained over the temperature range 790-1410 K.The upper temperature of this work exceeds, by some 400 K, the upper temperature of any 100)/T> reported kinetic study on this reaction.The data are fitted by the expression k₁(T)=(3,5+/-0.3) X 10^-11 exp<-(2300+/-100)/T> cm³s^-1. mechanistic studies near 1300 K showed that the reaction 1 is dominated by the abstraction channel, OH + C6H6<*>C6H5 + H2O (1a).The effecty of the reverse reaction, C6H5 + H2O<*>OH + C6H6 (-1a), was also observed at suitably chosen experimental conditions, and its rate coefficient, k_-1a was measured.The value of k_-1a, (10+/-0.3) X 10 ^-14 cm³s^-1, was found to agree with estimates obtained from the measured forward rate coefficient, k_1a, and available thermochemical data.The 1300 K work also showed that a nonabstraction channel recently proposed by ther workers on the basis of theoretical calculations, OH + C6H6<*>C6H5OH + H (1b), does not contribute significantly (<20percent) to the overall reaction rate.