Gas-Phase Reactions of Ozone and Olefin in the Presence of Sulfur Dioxide

Chemical kinetics of homogeneous atmospheric oxidation of sulfur dioxide

“…The general mechanism employed in the current study is given in Table IV. Two sets of stoichiometric coefficients are required: one for the propylene systems of Smith and Urone (27) and McNelis (44) and one for the 1-butene system of Wilson and Levy (45,46,55). Since the McNelis system contained no NO*, an explicit propylene mechanism, not presented here, was used in analyzing these experiments.…”

Photochemical aerosol formation. Sulfur dioxide, 1-heptene, and NOx in ambient air

“…Recent studies have indicated that oxidation of S02 by some reactive intermediate of the 0,3-olefin reaction can lead to the formation of aerosol sulfur (8,12,20). Other investigators have proposed the hydroxyl radical (19) or the hydroperoxyl radical (30) as a major contributor to the oxidation of S02 in the atmosphere.…”

“…No measurement of the distribution of sulfur compounds with respect to particle size has been made. Measurements have been reported of the total size distribution, as a function of time, in experiments with S02, propylene, and O3 (12).…”

Mechanism for olefin-ozone reactions

“…Although the calculated rate for Reaction 36 may be too high, it is doubtful that the contribution of the biradical to S02 oxidation is important. Since the product distribution is altered when S02 is added to an olefin-ozone system (13), it is possible that S02 does react with the biradical. However, the observed oxidation rates strongly imply that the S02-biradical rate constant is considerably smaller than 4 X 10°p pm~] min-1; if the reaction rate constant of CH3O9 with S02 is even close to correct, the total S02 oxidation can be accounted for without invoking any reaction with the biradical.…”