ch3misc00l
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New method for making sulfuric acid? .
If i bubble SO2 through Manganese Dioxide suspension in a Manganese sulfate solution , that is being electrolysed with graphite/mmo electrodes ,can i
get sulfuric acid? This is my equation:
MnO2 + SO2 = MnSO4
MnSO4 + 2H2O = H2SO4 + MnO2 + H2
MnO2 gets regenerated so the process is repeated.
I'm gonna try this soon as i made a sulfur dioxide generator and i have some good quality MnO2.
[Edited on 13-10-2015 by ch3misc00l]
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ave369
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MnO2 + SO2 = MnSO4
Never heard about this reaction. But if it really works, the method might be workable, and easier to implement than the other electric regenerative
method, NurdRage's electrobromine process. If this truly works, then my congratulations, looks like you've found the holy grail of unlimited sulfuric
acid works!
[Edited on 13-10-2015 by ave369]
Smells like ammonia....
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kecskesajt
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Yes, might work, but you need a membrane cell.And then you need to concentate the H2SO4 by boiling and then distillation.
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AJKOER
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Here is a new experimental path for something a little more interesting than H2SO4, in my opinion.
First saturate a solution with some SO2 and lots of N2O, and then treating the mix in the presence of added O2 to photolysis or pulse radiation from a
microwave. The expected product could include the aqueous HSO5- anion, or H2SO5, assuming it has not otherwised reacted. Some specifics:
SO2 + H2O = H2SO3 = HSO3- + H+
HSO3- + •OH → •SO3- + H2O
•SO3- + O2 → •SO5-
References: see page 143 at https://books.google.com/books?id=vVvrCAAAQBAJ&pg=PA143&... ), as a path to persulfate salts.
Also, see discussion on the sulfite radical on page 6 and the middle of page 7 at https://www.google.com/url?sa=t&source=web&rct=j&... and also http://pubs.acs.org/doi/abs/10.1021/jp011255h .
Now, there are many paths to the hydroxyl radical employed above, but some I have used include the action of either sunlight or pulse radiation on N2O
in the presence of water, for example, as I have documented previously on SM. Another, hydroxyl radicals can be generated from the photolysis of
aqueous nitrate or nitrite per the reactions:
NO3-(aq) + hv → •NO2 + •OH (see http://pubs.acs.org/doi/abs/10.1021/ja073609 )
Or, NO2-(aq) + hv → NO + •OH
Actually, more complex, see, for example, discussion on page 2 at https://www.google.com/url?url=http://scholar.google.com/sch...
[Edited on 14-10-2015 by AJKOER]
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ave369
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I think you also need some alkali in that. If I recall correctly, Caro's acid isn't terribly stable, unlike its salts.
Smells like ammonia....
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MeshPL
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The thing is you need H2O2. While I could buy a pool supply H2O2, I can also buy NaHSO4, which can also be turned into H2SO4.
Your method seems quite interesting. Indeed that MnO2 into MnSO4 was actually used by Nurdrage in one of his older videos. The only thing is, MnO2 is
a H2O2 decomposition catalyst I think.
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ave369
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Definitely an H2O2 decomposition catalyst, and quite a potent one.
Smells like ammonia....
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woelen
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Another method for making H2SO4 is with H2O2 and SO2.
Simply bubble SO2 through H2O2 until the liquid starts smelling of SO2. SO2 reacts quickly with H2O2:
SO2 + H2O2 --> H2SO4
Start with 10 ... 15% H2O2 and bubble in SO2. You'll get 20% or so H2SO4.
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MeshPL
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Actually, if I heat MnSO4 to a few hundred C, what it will decomlose into?
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woelen
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I would expect formation of MnO2 and SO2 and on further strong heating, loss of some oxygen and formation of Mn3O4.
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ave369
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Quote: Originally posted by woelen  | Another method for making H2SO4 is with H2O2 and SO2.
Simply bubble SO2 through H2O2 until the liquid starts smelling of SO2. SO2 reacts quickly with H2O2:
SO2 + H2O2 --> H2SO4
Start with 10 ... 15% H2O2 and bubble in SO2. You'll get 20% or so H2SO4. |
Obviously, the disadvantage of this method is that it processes a rare and prized reagent (H2O2 over 6%) into a cheap and easily bought one (dilute
sulfuric acid). But in a land full of artificial blondes and no cars, this method might be priceless.
[Edited on 15-10-2015 by ave369]
Smells like ammonia....
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blogfast25
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MnO2 + SO2 = MnSO4 works well.
MnSO4 + 2H2O = H2SO4 + MnO2 + H2. Electrolytically? I'd love to see it. Bear also in mind that sulphuric acid attacks MnO2 to form Mn(+3).
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byko3y
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Manganese, iron and other transitional metals can oxidize SO2 with O2 via radicals, there's a lot of publications on this route. For example, oxygen
oxidized Mn2+ to Mn3+ in MnSO4, then the sulfate is converted into MnSO5 (monopersulfate), the monopersulfate oxidizes H2SO3 into H2SO4, regenerating
the MnSO4 catalyst.
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woelen
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| Quote: Originally posted by ave369 | | Obviously, the disadvantage of this method is that it processes a rare and prized reagent (H2O2 over 6%) into a cheap and easily bought one (dilute
sulfuric acid). But in a land full of artificial blondes and no cars, this method might be priceless. |
There are quite a few places where H2SO4 is very hard to obtain, while 10% HCl, Na2SO3 (or NaHSO3), and 6% H2O2 are easy to obtain locally. From 6%
H2O2 you can make 10% H2SO4 and from HCl and (bi)sulfite you can easily make SO2 (simply mix and gently heat and you have a nice stream of SO2, I
tried this myself several times and it works fine). The reaction between SO2 and H2O2 is remarkably smooth and complete. Excess SO2 is easily driven
off by boiling the liquid.
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AJKOER
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| Quote: Originally posted by byko3y | | Manganese, iron and other transitional metals can oxidize SO2 with O2 via radicals, there's a lot of publications on this route. For example, oxygen
oxidized Mn2+ to Mn3+ in MnSO4, then the sulfate is converted into MnSO5 (monopersulfate), the monopersulfate oxidizes H2SO3 into H2SO4, regenerating
the MnSO4 catalyst. |
Here is a reference noting a preference for Cobalt over other transition metals with reaction speed increasing with pH ( source: "Catalytic
Decomposition of Potassium Monopersulfate. Influence of ...", link https://www.google.com/url?sa=t&source=web&rct=j&... ) .
Interestingly, the author notes a non-transitional metals path of simply applying "radiant energy".
I should have noted in my prior comments citing hydroxyl radicals and O2 as inputs to the reaction, that these are, of course, formed in an
electrolysis approach as well.
Once the monopersulfate anion has been formed, the paper cited on the decomposition of potassium monopersulfate in aqueous solution in the presence of
Co(II), gives some guidance on what happens next.
[Edited on 15-10-2015 by AJKOER]
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byko3y
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You are talking about production of sulfate/bisulfate, I'm talking about production of sulfuric acid.
ch3misc00l, "MnSO4 + 2H2O = H2SO4 + MnO2 + H2" - how is it supposed to be performed?
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ch3misc00l
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| Quote: Originally posted by byko3y | You are talking about production of sulfate/bisulfate, I'm talking about production of sulfuric acid.
ch3misc00l, "MnSO4 + 2H2O = H2SO4 + MnO2 + H2" - how is it supposed to be performed? |
First, you start with a MnSO4 solution. Then it is electrolysed. It produces MnO2 and H2SO4. But if you bubble SO2 through the solution the MnO2 will
react to produce more MnSO4. At the end you need to stop bubbling SO2 and then filter it to get the clean H2SO4.
| Quote: Originally posted by kecskesajt | | Yes, might work, but you need a membrane cell.And then you need to concentate the H2SO4 by boiling and then distillation. |
As far i know, pure H2SO4 doesn't react with MnO2 (at least the reaction is not detectable).
Ok. I just tried this method. It works.I distilled the acid and it is enough concentrated that it reacts with sugar. But my setup has a problem: the
sulfur dioxide must be in bubbled in excess to completely react the MnO2 produced , and the amperage must be high (more than 5 amps) to produce MnO2
as fast as possible to react it with the SO2, and prevent loss of the gas. It is a bit tedious to add more sulfur to the SO2 generator when it is
exhausted (every 15 min) and re-light it to keep the reaction going.
If someone has an efficient sulfur dioxide generator and a high amperage power supply, it can be a very good method to produce medium amounts of
sulfuric acid.
[Edited on 17-10-2015 by ch3misc00l]
[Edited on 17-10-2015 by ch3misc00l]
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