HENRYS LAW SOLUBILITIES AND SETCHENOW COEFFICIENTS FOR BIOGENIC REDUCED SULFUR SPECIES OBTAINED FROM GAS-LIQUID UPTAKE MEASUREMENTS

Biogenically produced reduced sulfur compounds, including dimethylsulf ide (DMS, CH3SCH3), hydrogen sulfide (H2S), carbon disulfide (CS2), me thyl mercaptan (CH3SH), and carbonyl sulfide (OCS), are a major source of sulfur in the marine atmosphere. This source is estimated to contr ibute 25-40% of global sulfur emissions. These species and their oxida tion products, dimethyl sulfoxide (DMSO), dimethyl sulfone (DMSO(2)), and methane sulfonic acid (MSA), dominate the production of aerosol an d cloud condensation nuclei (CCN) in the clean marine atmosphere, The multiphase chemical processes for these species must be understood in order to study the evolving role of combustion-produced sulfur oxides over the oceans. Using a newly developed bubble column apparatus, a se ries of aqueous phase uptake studies have been completed for the reduc ed sulfur species DMS, H2S, CS2, CH3SH, and OCS. Aqueous phase uptake has been studied as a function of temperature (278-298 K), pH (1-14), H2O2 concentration (0-1 M), NaCl concentration (0-5 M), and (NH4)(2)SO 4 concentration (0-4 M). The Henry's law coefficients for CH3SH and CS 2 were determined for the first time, as were the Setchenow coefficien ts for all, the species studied.