Rate coefficients for the gas-phase reaction of OH radicals with dimethyl sulfide: temperature and O2 partial pressure dependence.
Rate coefficients for the gas-phase reaction of hydroxyl (OH) radicals with dimethyl sulfide (CH(3)SCH(3), DMS) have been determined using a relative rate technique. The experiments were performed under different conditions of temperature (250-299 K) and O(2) partial pressure (approximately 0 Torr O(2)-380 Torr O(2)), at a total pressure of 760 Torr bath gas (N(2) + O(2)), in a 336 l reaction chamber, using long path in situ Fourier transform (FTIR) absorption spectroscopy to monitor the disappearance rates of DMS and the reference compounds (ethene, propene and 2-methylpropene). OH was produced by the photolysis of H(2)O(2). The following Arrhenius expressions adequately describe the rate coefficients as a function of temperature (units are cm(3) molecule(-1) s(-1)): k = (1.56 +/- 0.20) x 10(-12) exp[(369 +/- 27)/T], for approximately 0 Torr O(2); (1.31 +/- 0.08) x 10(-14) exp[(1910 +/- 69)/T], for 155 Torr O(2); (5.18 +/- 0.71) x 10(-14) exp[(1587 +/- 24)/T], for 380 Torr O(2). The results are compared with previous investigations.
Bergische Universität Wuppertal, Physikalische Chemie/FB C, Gauss Strasse 20, D-42097 Wuppertal, Germany.
Mihaela
M
Albu
Ian
I
Barnes
Karl H
KH
Becker
Iulia
I
Patroescu-Klotz
Raluca
R
Mocanu
Thorsten
T
Benter
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D005740:Gases / Q000737:chemistry; D017665:Hydroxyl Radical / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D010313:Partial Pressure; D013440:Sulfides / Q000737:chemistry*; D013696:Temperature
D005740:Gases; D013440:Sulfides; D017665:Hydroxyl Radical; C004784:dimethyl sulfide; D010100:Oxygen