Oxidation ot sultur compounds. I. The photolysis of CH3SH and (CH3S)2 in the presence of NO

Abstract

Both CH3SH and (CH3S)2, as well as their mixtures, were photolyzed in the presence of NO at 23 ± 1 °C. The photolyses were carried out in a 631 mL quartz vessel with a pinhole bleed to a quadrupole mass spectrometer for continual analysis of products. After the termination of exposure, further product analysis was made by gas chromatography.The identified products of the reaction were CH3SNO, (CH3S)2, H2, and N2. Hydrogen atoms, formed from the photolysis of CH3SH, reacted with both NO and CH3SH:[Formula: see text]with k5/k4 = 626 ± 42 Torr for NO as a chaperone. The CH3S radical adds to NO[Formula: see text]with k−2a/k2b = 83 ± 52 Torr. As the CH3SNO accumulates, CH3S also reacts with CH3SNO[Formula: see text]with [Formula: see text]. At high NO pressures a chain process occurs which is attributed to:[Formula: see text]where ξ is probably 4.0. Termination is most easily represented by[Formula: see text]with k8/k7 = 85.0 ± 7.8 Torr