Investigation of the cross-reaction mechanism of C6H5F-HNO2 aqueous solution irradiated at 355 nm by transient absorbance spectrum technique

摘要

The transient absorption spectrum technique was employed to investigate the cross-reaction mechanism of C6H5F-HNO2 aqueous solution irradiated at 355 nm. The characteristic and the kinetic parameters of transient species were also detected. Hydroxyl radical derived from the photolysis of HNO2 was added to monofluorobenzene with a second-order rate constant of (5.83 +/- 0.17)x10(9) L.mol(-1).s(-1) to form an adduct, C6H5F center dot center dot center dot OH, which was able to react with HNO2 as the main reaction pathway with a rate constant of (8.3 +/- 0.1)x10(7) L.mol(-1)-s(-1). The C6F6 center dot center dot center dot OH adduct can also be decayed by elimination of H2O to yield monofluorophenyl radical C6H4F.. By GC-MS technique, the final products were identified to be monofluorophenol, nitro-monofluorobenzene, nitro-monofluorophenol and para-fluorobiphenyl.