We studied the role of elemental sulfur (S8) in activation of water that lead to the oxidation and sulfurization of organic compounds at relatively low temperatures. Pyrolysis experiments were performed with elemental sulfur, 1-octene and water in the pH range of 8-8.5 at temperatures of 100-130°C. The results presented in this study show that elemental S8 in water disproportionates under these conditions to form H2S and SO42-. A variety of sulfurized and oxidized organic compounds formed in parallel during this reaction. Formation of 2-octanone indicates the involvement of hydroxyl radicals in this reaction. This study shows that the action of S8 on organic compounds (OC) in the presence of water is twofold: water is activated to produce hydroxyl radicals that can oxidize organic compounds and sulfur reacts directly with OC via thiyl radical (HS) to produce organosulfur compounds and H2S. The findings of the study improve understanding of the reactivity of carbon, oxygen and sulfur in the geosphere under much milder environmental conditions than previously suggested.
Bibliographical noteFunding Information:
W.S.A and A.A thank the Israeli Science Foundation (Grant 1269/12) for partial support of this study.