| Title: | Photochemical Production of Sulfate and Methanesulfonic Acid from Dissolved Organic Sulfur |
| Author(s): | Ossola R; Tolu J; Clerc B; Erickson PR; Winkel LHE; McNeill K; |
| Address: | "Institute of Biogeochemistry and Pollutant Dynamics (IBP), Department of Environmental System Science , ETH Zurich , 8092 Zurich , Switzerland. Eawag Swiss Federal Institute of Aquatic Science and Technology , 8600 Dubendorf , Switzerland" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
| Abstract: | "Photodegradation processes play an important role in releasing elements tied up in biologically refractory forms in the environment, and are increasingly being recognized as important contributors to biogeochemical cycles. While complete photo-oxidation of dissolved organic carbon (to CO(2)) and dissolved organic phosphorous (to PO(4)(3-)) has been documented, the analogous photoproduction of sulfate from dissolved organic sulfur (DOS) has not yet been reported. Recent high-resolution mass spectrometry studies showed a selective loss of organic sulfur during photodegradation of dissolved organic matter, which was hypothesized to result in the production of sulfate. Here, we provide evidence of ubiquitous production of sulfate, methanesulfonic acid (MSA), and methanesulfinic acid (MSIA) during photodegradation of DOM samples from a wide range of natural terrestrial environments. We show that photochemical production of sulfate is generally more efficient than the production of MSA and MSIA, as well as volatile S-containing compounds such as CS(2) and COS. We also identify possible molecular precursors for sulfate and MSA, and we demonstrate that a wide range of relevant classes of DOS compounds (in terms of S oxidation state and molecular structure) can liberate sulfate upon photosensitized degradation. This work suggests that photochemistry may play a more significant role in the aquatic and atmospheric fate of DOS than currently believed" |
| Keywords: | Mesylates Photochemical Processes Sulfates *Sulfur *Sulfur Oxides; |
| Notes: | "MedlineOssola, Rachele Tolu, Julie Clerc, Baptiste Erickson, Paul R Winkel, Lenny H E McNeill, Kristopher eng 2019/10/11 Environ Sci Technol. 2019 Nov 19; 53(22):13191-13200. doi: 10.1021/acs.est.9b04721. Epub 2019 Nov 5" |
