Thermal Decomposition of Methyl Phenyl Ether in Shock Waves: The Kinetics of Phenoxy Radical Reactions

Article abstract of DOI:10.1021/j100275a014

The unimolecular decomposition of methyl phenyl ether (anisole) was studied in incident shock waves covering the temperature range from 1000 to 1580 K and the pressure range from 0.4 to 0.9 atm.The CO formed in the reaction, monitored by resonance absorption using a stabilized CW CO laser, could be satisfactorily accounted for by a four-reaction mechanism: C6H5OCH3->C6H5O+CH3 (1), C6H5O->CO+C5H5 (2), CH3+C6H5O->o- and p-CH3C6H4OH (3), and CH3+CH3->C2H6 (4).Kinetic modelling of observed CO production profiles based on the above mechanism with 70 sets of data led to k1<*>(1.2+/-0.3)*10¹⁶exp(-33100/T) s^-1, k2=10^11.40+/-20exp(-22100+/-450/T) s^-1, and k3=(5.5+/-2.0)*10¹¹ cm³*mol^-1*s^-1.The relatively low A factor and activation energy measured for the phenoxy radical decomposition reaction support the mechanism A involving a tight intermediate.