ABSTRACT This article reviews the literature on the oxidation of H2S by various oxidants, including oxygen, hydrogen peroxide, iodate, chromate, ferrate, Fe(III) hydroxides and Mn(IV) oxides, in natural waters. The rates of H2S oxidation increased with oxidants in a order of chromate, oxygen, hydrogen peroxide, iodate, Fe(III) hydroxides, Mn(IV) oxides and ferrate. Effect of pH on the rates of oxidation by various oxidants indicated that HS- is a reactive species while H2S is less reactive or, in some cases, non-reactive. The oxidation by oxygen has been a subject of extensive studies and its rates have been measured over a wide range of environmental conditions, such as pH, temperature and salinity. Dissolved and particulate metals have a significant effect on the rates of oxidation and the product formation. The reaction conditions and resulting product formation (S, Sn2-, SO3 2-, S2O3 2-and SO42-) were examined to unravel the reaction pathway.
Buy this Article
|