adsorption on the C surface, ( Eq. (2)) H2S dissolution in a water film, (Eq. (3)) dissociation of H2S in an adsorbed state in the water film, (Eq. (4a)) surface reaction of adsorbed O2 with the formation of elemental sulfur (Eq. (4b)) or sulfur dioxide, and (Eq. (5)) further oxidation of SO2 to H2SO4 in the presence of water (Adib et al., 2000, 1999a,b).