Henry's law solubilities and Śetchenow coefficients for biogenic reduced sulfur species obtained from gas‐liquid uptake measurements

Abstract

Biogenically produced reduced sulfur compounds, including dimethylsulfide (DMS, CH 3 SCH 3 ), hydrogen sulfide (H 2 S), carbon disulfide (CS 2 ), methyl mercaptan (CH 3 SH), and carbonyl sulfide (OCS), are a major source of sulfur in the marine atmosphere. This source is estimated to contribute 25–40% of global sulfur emissions. These species and their oxidation products, dimethyl sulfoxide (DMSO), dimethyl sulfone (DMSO 2 ), and methane sulfonic acid (MSA), dominate the production of aerosol and 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 series of aqueous phase uptake studies have been completed for the reduced sulfur species DMS, H 2 S, CS 2 , CH 3 SH, and OCS. Aqueous phase uptake has been studied as a function of temperature (278–298 K), p H (1–14), H 2 O 2 concentration (0–1 M), NaCl concentration (0–5 M), and (NH 4 ) 2 SO 4 concentration (0–4 M). The Henry's law coefficients for CH 3 SH and CS 2 were determined for the first time, as were the Setchenow coefficients for all the species studied.