Determining the Right Reaction: 2 H_2S + O2

[katchum]

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.

 

[Chestermiller]

I don't see how the OP can say that the dew point of S is 440 C, without knowing the mole fraction and pressure of the gas phase.