SO₂ Uptake on Oleic Acid: A New Formation Pathway of Organosulfur Compounds in the Atmosphere

Abstract

SSCI-VIDE+CARE+JSH:MPI:YDU:RCI:LTI:SRS:CGOInternational audienceOrganosulfates are tracers for secondary organic aerosol (SOA) formation. We propose a new mechanism of organosulfur product formationin the atmosphere, in which sulfur dioxide (SO2) reacts directly withalkenes. The experiments were conducted at the gas-liquid interface witha coated-wall flow tube reactor. It was shown, for the first time, thatSO2 reacts efficiently with the unsaturated bond in oleic acid underatmospheric conditions (without ozone), leading to the formation of C-9and C-18 organosulfur products. The associated uptake coefficients werein excess of 10(-6), decreasing with initial SO2 concentration andincreasing with humidity. These results might explain a fraction oforganosulfur products detected in atmospheric particles. This work tendsto elucidate the role of organosulfates' interfacial chemistry as apotentially unrecognized pathway for their contribution to SOAformation; however, it remains to be determined how significant thispathway is to the overall organosulfate abundances measured in ambientaerosol

Novel pathway of SO<sub>2</sub> oxidation in the atmosphere: reactions with monoterpene ozonolysis intermediates and secondary organic aerosol

“…However, it was highlighted that in polluted areas, dissolved NO 2 and heterogeneous reactions on the surface of mineral dust could also contribute significantly to atmospheric SO 2 oxidation Xue et al, 2016). More recently, Shang et al (2016) and Passananti et al (2016) proposed that, without assistance of other oxidants, gaseous SO 2 can also be directly taken up by unsaturated fatty acid or long-chain alkenes through a [2 + 2] cycloaddition mechanism under atmospheric conditions with observation of organic sulfur compounds as direct formation products.…”

Organosulfates in atmospheric aerosol: synthesis and quantitative analysis of PM<sub>2.5</sub> from Xi'an, northwestern China

“…Chamber studies have found that the oxidation of biogenic volatile organic compounds (BVOCs) including isoprene, monoterpenes and sesquiterpenes can form organosulfates on acidified sulfate particles (e.g., Surratt et al, 2008;Iinuma et al, 2007;Chan et al, 2011;Zhang et al, 2012). A very recent study revealed a previously unrecognized pathway for organosulfate formation through the heterogeneous reaction of SO 2 with the unsaturated bond in oleic acid (Shang et al, 2016). A number of biogenic organosulfates have been observed in ambient aerosol, in particular, isoprene-derived organosulfates (e.g., Kristensen et al, 2011;He et al, 2014;Liao et al, 2015;Budisulistiorini et al, 2015).…”

Organosulfate Formation through the Heterogeneous Reaction of Sulfur Dioxide with Unsaturated Fatty Acids and Long‐Chain Alkenes

“…Therefore,k nowledge of the chemistry of SO 2 is essential for the understanding of some major atmospheric processes,s uch as particle formation. [3] It was shown that ah eterogeneous reaction between SO 2 and oleic acid (OA; an unsaturated fatty acid) takes place and leads efficiently to the formation of organosulfur products.H erein, we demonstrate that this reaction proceeds on various unsaturated compounds,and may therefore have ageneral environmental impact. Despite having similar electronic structures,SO 2 and O 3 react differently with alkenes.The well-known [3+ +2] cycloaddition of O 3 to alkenes is not favored for SO 2 ,w hile the [2+ +2] cycloaddition of SO 2 to the C = Cb ond is more favorable compared to the analogous reaction with O 3 .…”

“…[3] Theu ptake coefficients of SO 2 (g SO 2 )o nO A were measured for exposure of OA films to SO 2 in dry synthetic air,n itrogen, synthetic air with added O 3 ,s ynthetic air with 30 %relative humidity (RH), and in dry synthetic air under UV/Vis irradiation. [3] Theu ptake coefficients of SO 2 (g SO 2 )o nO A were measured for exposure of OA films to SO 2 in dry synthetic air,n itrogen, synthetic air with added O 3 ,s ynthetic air with 30 %relative humidity (RH), and in dry synthetic air under UV/Vis irradiation.…”