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Interests in the gas phase oxidation reactions of organic sulfur compounds such as thiols, sulfides, and disulfides have become increasingly important due to their potential role in the formation of tropospheric and stratospheric sulfur containing aerosols. The rate constants for the reaction of OH with CH3SH and C2H5SH have been determined under pseudo‐first‐order conditions, using the discharge flow‐resonance fluorescence technique. The measured room temperature rate constants are (2.56±0.44)×10−11 and (3.67±0.18)×10−11 cm3 molecule−1 s−1 for CH3SH and C2H5SH, respectively. The CH3SH results are compared to those of previous studies, employing different experimental techniques.

Interests in the gas‐phase oxidation of organic sulfur compounds have become increasingly evident due to the important roles that these compounds may play in combustion processes, atmospheric chemistry, and photochemical air pollution. The rate constants for the reaction of O(3P) with thiophene (C4H4S) have been determined for the first time under pseudo‐first‐order reaction conditions, using the discharge flow–resonance fluorescence technique. The measured rate constants over a temperature reange 262–448 K are well represented by the Arrhenius expression k = (3.34±0.34)×10−11exp[−(1130±60)/RT] cm3 molecule−1 s−1. However, a discontinuity in the Arrhenius plot is noted around 262 K. The results are discussed in terms of different reaction pathways and compared with other compounds having similar molecular structures and various reactivities.

Rate constants for the oxidation reactions of organic sulfur compounds have become increasingly important due to their potential role in the formation of tropospheric and stratospheric sulfate aerosols. The present study deals with the reaction of the ground state oxygen atom with dimethyl sulfide. A discharge fast flow–resonance fluorescence technique was used to follow the decay of O(3P) atoms in the presence of excess CH3SCH3 under pseudo‐first‐order conditions. Kinetic data, obtained over the temperature range 272 to 472 K, are well represented by the Arrhenius expression, kbi= (1.28±0.12) ×10−11 exp[(803±60)/RT] cm3 molecule−1 sec−1. The results are compared to those of previous studies which employed different experimental techniques.

Rate constants for the oxidation reactions of organic sulfur compounds have become increasingly important due to the potential role of these compounds in the formation of tropospheric and stratospheric sulfate aerosols. The present study deals with the reaction of the ground state oxygen atom with dimethyl disulfide (DMDS). The discharge fast flow–resonance fluorescence technique was used to monitor the decay of O(3P) concentration in the presence of excess CH3SSCH3 under pseudo‐first‐order conditions. Over a temperature range from 270 to 329 K, and a pressure range from 0.52 to 2.60 Torr, no variation of the rate constant with temperature and pressure was observed. The results are best represented by the temperature and pressure independent value of (2.12±0.22)×10−10 cm3 molecule−1 s−1, which is about one‐half the theoretical collision frequency. The zero activation energy for this reaction is discussed in terms of the temperature dependence of other sulfur compound–oxygen atom reactions reported in the ...

Interests in the gas phase oxidation of heterocyclic organic compounds containing oxygen, nitrogen, or sulfur have become increasingly evident due to the important roles that these compounds may play in combustion processes, atmospheric chemistry, and photochemical air pollution. The rate constants for the reactions of OH with furan (C4H4O) and thiophene (C4H4S) have been determined for the first time under pseudo‐first‐order conditions, using the discharge flow‐resonance fluorescence technique. The measured room temperature rate constants are (2.31±0.40)×10−13, (1.05±0.08)×10−10, and (4.77±0.63)×10−11 cm3/molecule−1 s−1 for ethane, furan, and thiophene, respectively. The results are discussed in terms of structural differences and probable reaction pathways.