Some recent measurements of H₂S oxidation rates and their implications to atmospheric chemistry

Abstract

The general belief that significant fractions of atmospheric sulfur are donated naturally from the earth's surface in the form of hydrogen sulfide and/or its organic homologs implies that atmospheric breakdown of these materials must be a rather fast process. It has been expected that oxidation of these materials by atmospheric ozone should contribute significantly in accomplishing this breakdown; and experimental measurements have been published which do, indeed, indicate rapid ozone oxidation rates, corresponding to lifetimes of the order of hours under typical tropospheric conditions. This paper discusses some later experimental measurements on H2S ozone reaction rates which disagree with former determinations, predicting typical H2S lifetimes of the order of months—much too long for this reaction to be a significant mechanism of atmospheric removal. The results also indicate the H2S ozone reaction should be expected to proceed homogeneously in the atmosphere, with catalytic effects being of little or no importance. The reaction proceeds thermally; light in the visible region does not affect its rate appreciably. These measurements indicate that some mechanism(s) other than ozonation must be responsible for atmospheric breakdown of reduced sulfur compounds. Final portions of the paper examine some possibilities for these mechanisms.

Chemical stability of Li4PS4I solid electrolyte against hydrolysis

“…The detection of the H2S gas stabilized at the maximum peak for a certain time and subsequently decreased in both cases. It is believed that the H2S gas could undergo certain reaction in air 31 , which would prevent the further detection of the H2S gas generation.…”

Development of a relationship between olfactory response and major odorants from organic wastes

“…This was expected, because sulphides are chemically active and can stick to surfaces as well as oxidise. 27 OC increased with both H 2 S and acetic acid concentrations but was negatively correlated with the concentration of FMP.…”

Impact of gaseous sulfur and aerosols produced by power plants on the CCN budget. Progress report, September 1, 1978-August 31, 1979

“…Globally, 1.33 x 10-149 of sulfur results from the conversion of H2S (Hales et al, 1974) or SO2 into sulfates each year (Friend, 1973). This is equivalent to the annual production of 4.2 x 10 moles of sulfate.…”