Dimethylsulfide (CH3SCH3, DMS) is one of the major natural organic sulfur compounds emitted to the atmosphere [Aneja and Cooper, 1989], and consequently much effort has been directed towards understanding its oxidation mechanisms particularly with the OH radical [Yin et al., 1990; Tyndall and Ravishankara, 1991]. All of the product studies on the reaction of OH with DMS have been carried out at room temperature and no information is currently available on the effects that temperatures such as those prevalent in the Arctic or Antarctic may have on the product distributions. For example, results from field measurements in the remote Southern Hemisphere show a higher yield of methanesulfonic acid (CH3SO3H, MSA) and a lower yield of SO2 from DMS oxidation compared to other world areas [Berresheim et al., 1989, 1990], suggesting a change in the product distribution at low temperatures. The various mechanistic and product studies indicate that the products of the oxidation of DMS will be very much dependent on the atmospheric fate of the initially formed OH-DMS adduct and also the intermediate CH3S radical whose loss will be controlled by reactions with either O2 or trace species such as O3 and NOx. The kinetics and mechanisms of the reactions of CH3S and O2, O3 and NOx are still speculative.
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- Oxidation of Organic Sulfur Compounds
K. H. Becker
R. D. Overath
- Springer Berlin Heidelberg