guy
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Hydrogen reducing copper ions
Hydrogen can be used to reduce hot copper(II) oxide to pure copper and water. If this is possible, can hydrogen reduce heated copper(II) sulfate to
copper and sulfuric acid?
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woelen
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I do not believe this will happen. I expect that at the high temperatures involved, not only the copper (II) is reduced, but also the SO3, which is
part of the sulfate ion.
CuSO4 + 2H2 --> Cu + 2H2O + SO2
I also expect some side reactions, leading to formation of S, H2S and possibly also some SO3/H2SO4, but I believe that the equation describes the main
reaction best.
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unionised
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Copper is capable of reducing sulphuric acid.
Hydrogen is a better reducing agent than copper.
Hydrogen can reduce sulphuric acid.
Of course, that's a different matter from saying it will reduce it.
It may be possible (perhaps using a Pt catalyst) to get this reaction to work without reducing the acid.
ie H2 +CuSO4 --> 2Cu +H2SO4.
I always hated electrochemistry but if anyone out there is good at it they might want to look at a cell with a Cu electrode and an H2 (Pt) electrode
in a solution of CuSO4/ H2SO4. I think it would work (ie generate power and produce acid from CuSO4)
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12AX7
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Without a doubt, that'll work, at least until it gets too concentrated and the equilibrium starts dissolving copper (resulting in SO2 then). Cooling
should help that.
For that matter, could Pt + H2 reduce SO4 in solution?
Problem with making concentrated acid is 1. you need to filter it, 2. you need SOME water, somehow, to get it started in the first place. If you
don't mind boiling down acid I suppose you could wash the precipitate 'til your heart's content and get out all the acid.
Tim
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mantis
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Pt(or Pd)+H2 should be better, because in this case the hydrogen is atomic.
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guy
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So, only Pt or Pd, expensive metals will work? So Im guessing the function of this catalyst is to weaken the bonds of hydrogen. Will any others
work?
Does anyone know of any sources that talk about how catalyst work and how to choose catalysts?
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mantis
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It will also work under pressure, without Pt or Pd.
But I think you need only some dust of these metalls, maybe 0,1-0,5g. Palladium is not so expensive and can save more H2.
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guy
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Which is better, electrolysis with Pt or bubbling H2 with a Pt catalyst? I can't think of a design that will make the Pt come into contact with H2
well.
I'm thinking a wide sheet of Pt submerged under CuSO4(aq) and bubble the H2 under the sheet. How fast will the the reaction usually take place
because I wouldnt want the H2 bubbling away? And can this proceed at room temp? Thanks
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