Question #82a89

1 Answer
Jun 20, 2016

I think you need to research the contact process.

Explanation:

AFAIK, elemental sulfur is oxidized stepwise to give #SO_3#:

#S(s) +O_2(g)rarrSO_2(g)#

#2SO_2(g) + O_2(g) rarr 2SO_3(g)#

The sulfur trioxide could be directly treated with water to give #H_2SO_4#. I have seen a couple of plants, and it is an incredibly dirty and smelly process. Of course, both oxidations are catalyzed; I think supported #V_2O_5# is the catalyst of choice.

One thing the reaction has got going for it, is that both oxidations are exothermic. Sulfur trioxide may be directly converted to sulfuric acid:

#SO_3(g) + H_2O(g) rarr H_2SO_4(aq)#

But this opens another can of worms. Usually sulfuric acid is reacted directly with sulfur trioxide to give oleum, #H_2S_2O_7#, which is the feedstock for #H_2SO_4#.