I have a rather uneasy question: Is the reaction the following? 2 H_2S + O2 = S_2 + 2 H_2O or 2 H_2S + O2 = 2S + 2 H_2O The dewpoint of S = 440 °C, but on my sketch I see the catalytic reactors are processed at 520 K = 250 °C which would mean that sulphur would become liquid again at that temperature, damaging the catalysts. So I think the first reaction is the right one. But: everywhere on the internet they speak of S and not S_2. Does someone know for sure which is the right reaction? And what's the dew point of S_2? I can't find it anywhere on the internet.