Hydrogen Sulphide and Steam Reaction?

You'd have to burn the hydrogen sulphide to get water and sulfur dioxide, and go from there--if I remember right, lead chamber process.

Al

No. The only commercial process (the DuPont Process) I am aware of involved burning molten sulfur to SO2, scrubbing the moisture out with fuming sulfuric acid,, then furthur oxidizing to SO3 using a catalyst, and then absorbing the SO3 in 93% sufluric acid to make 103% (fuming H2SO4) .

It is far better to convert the H2S to Sulfur in a conventional Claus process plant, then burn the sulfur. You can generate HP and LP steam in the Claus plant and HP steam in the Acid plant. Burning H2S directly significantly increases size and operating cost

You could look at a thiobacillus bioreactor, that converts H2S to H2SO4, though they concentrations are diluted to around pH 2 at best. You would then need to celan the H2SO4 and remove excess water. Thiobacillus is responsible for acid mine waste forming from sulfide minerals. I however, think this would not be cost effective given the much slow production and the large space requirements relative to current chemnical processes.

No, there isn't. H₂S and H₂O are in intimate contact in volcanic processes that occur naturally, and there isn't a reaction between them.

To make H₂SO₄ one needs to make SO₃ first, which requires O₂ and something to initiate a combustion reaction. SO₃ dissolved in liquid H₂O makes H₂SO₄.

Actually, combustion gives you SO2, you then have to combust the SO2 further in the presence of a catalyst to get SO3, which you absorb into concentrated sulfuric acid.

Also H2S occurs in many other natural water in reduced conditions, e.g. swamps, deep groundwaters, etc., and minerals, pyrrite, etc.. It will acidify the water if the oxygen content increases, due to biological reaction. This is one of the common chemiphilic reactions thermophiles living around underwater volcanic vents use for energy.

Alternately, microbes generate SO3 from H2S in surface redox conditions in the presence of water, this is why sewer pipes corrode so badly in the roof.

Thanks people.

Just to give a bit more background. The question arose because of an application for mechanical seals on pumps. When pumping hot hydrocarbons (greater than 175ºC for instance) it is customary to use a low pressure steam 'quench' at the atmospheric side, assuming a single seal is used. The primary purpose of this quench is to prevent coking of any slight seal leakage on coming in contact with atmosphere. If the pumped hydrocarbon contains hydrogen sulphide then I have seen the statement, that 'the mixture of steam and H2S could form Sulphuric Acid and cause corrosion'.

Leaving aside the question of whether a single seal should be used on this sort of duty, I have always doubted the above statement and your replies seem to confirm this.

A water quench is also sometimes applied on duties containing H2S and a similar statement regarding H2S reaction has been made. Again I doubted this.

Thanks for the replies.