Effect of CH_3OOH on the atmospheric concentration of OH radicals

Peroxides play an i mportant role in atmosphericchemistry,because they are not only amongthe prin-ciple oxidants in the chemical conversion of O3andSO2,but also act as an atmospheric sink and tempo-rary reservoir for i mportant oxidizing radicals such asOH, HO2and RO21 ,2]. With the development ofmeasurement techniques , several organic peroxideswere identified in the atmosphere in addition to hy-drogen peroxide (H2O2)3—5]. And among these or-ganic peroxides , methyl hydroperoxide ( MH…

Effect of CH3OOH on the atmospheric concentration of OH radicals

Methyl hydroperoxide (CH3OOH, MHP) is known to be a significant sink and reservoir of HOx and ROx radicals in the atmosphere. In order to investigate the impact of MHP on the concentration of atmospheric OH radicals, two key gas-phase reactions of MHP, i.e. the reactions with OH radicals and with UV photolysis, have been simulated at temperature of 293 ± 2 K and total pressure of 1.01 × 105 Pa, using the long path Fourier transform infrared (LP-FTIR) spectrometry. OH radicals are generated by the photolysis of O3 in the presence of water vapor. Combined with the relative rate method, the reaction rate constant of MHP with OH radicals is determore, from detailed analysis of the UV photolysis of MHP, the yield of OH radicals is obtained to be 0.91 ± 0.04. Based on the MHP atmospheric lifetime and the yield of OH radicals, it is concluded that MHP plays an essential role in the redistribution of OH radicals in the troposphere.