CH3CH2SCH3 + OH radicals: temperature-dependent rate coefficient and product identification under atmospheric pressure of air

OKSDATH MANSILLA, GABRIELA

JOURNAL OF PHYSICAL ORGANIC CHEMISTRY

JOHN WILEY & SONS LTD

Año: 2010 p. 925 - 925

0894-3230

span>Relative rate coefficients have been determined for the gas-phase reaction of hydroxylradicals with ethyl methyl sulfide using isobutene as reference compound. Theexperiments were performed in a 1080 L quartz glass photoreactor over the temperaturerange 286-313 K at a total pressure of (760 ± 10) Torr synthetic air using in situ FTIRabsorption spectroscopy to monitor the concentration-time behaviors of reactants andproducts. Hydroxyl radicals (OH) were produced by the 254 nm photolysis of hydrogenperoxide (H2O2).The kinetic data obtained was used to derive the following Arrhenius expression validin the temperature range 286-313 K (in units of cm3 molecule-1 s-1):k = (3.03 ± 0.6) x 10-15 exp [(2457 ± 65)/T]The rate coefficient displays a negative temperature dependence and low preexponentialfactor which supports the existence of an addition mechanism for the reaction involvingreversible OH-adduct formation. Th