Oxidation of H2S at atmospheric pressure has been studied under different reaction atmospheres, varying the air excess ratio (lambda) from reducing (lambda = 0.32) to oxidizing conditions (lambda = 19.46). The experiments have been carried out in a tubular flow reactor, in the 700-1400 K temperature range. The concentrations of H2S, SO2 and H-2 have been determined and the experimental results have been simulated with a detailed chemical mechanism compiled in the present work. The experimental results obtained indicate that H2S consumption is shifted to lower temperatures as the stoichiometry increases, starting at 925 K for reducing conditions and at 700 K for the most oxidizing ones. The model reproduces well, in general, the experimental data from the present work, and those from the literature at high pressures. Supported by theoretical calculations, the isomerization of HSOO to HSO2 has been determined as an alternative and possible pathway to the final product SO2, from the key SH + O-2 reaction. (C) 2018 The Combustion Institute. Published by Elsevier Inc. All rights reserved.
