Sciencemadness Discussion Board

peracetic acid solution

eisenhouer - 11-1-2017 at 09:51

I found that sodiumpercarbonate is sometimes used also as
a solid form of hydrogenperoxide. Now I react this with a
80% solution of acetic acid where the per acid forms ( am
i correct ? ). I found that H2O2 and acetic acid forms
peracetic acid. So is it not handy using the sodiumpercarbonate
so one can make a good concentrated solution of per-aceticacid ?
Text

Tsjerk - 11-1-2017 at 10:14

Depends on what you want to do with it

NitratedKittens - 12-1-2017 at 05:05

The main problem is that the acetic acid and the carbonate react to form sodium acetate wich cannot hold hydrogen peroxide.

alking - 12-1-2017 at 16:55

It should still work depending what you want to do with it though, you just need to use more acetic acid to account for it. All I would personally find a use of it for is sterilization/surface disinfecting, but I would not want to use a solution with NaOAc in it since it would leave a residue behind. You could purify it, but then it's easier just to start with H2O2 at that point.

theswitch - 18-1-2017 at 12:08

I think were is the need I do for doing some experimenting
Ive dissolved some sodiumpercarbonate in 115ml water
and stirr for some time,, Cann you distill to purify to end
up with plain hydrogenperoxide solution:P. For the better
part I doing some time thinking where I can use it for :-)

Tsjerk - 18-1-2017 at 23:49

Believe me, you don't want to distill hydrogen peroxide.

PHILOU Zrealone - 19-1-2017 at 09:45

Quote: Originally posted by Tsjerk  
Believe me, you don't want to distill hydrogen peroxide.

At best he will get the Na percarbonate back while water distills off and at worst he loses his percarbonate by overheating and ends up with Na carbonate. ;):P:D:)

Na percarbonate + water (l)
--> agitation --> distillation
--> Na percarbonate (s) or Na carbonate (s) + water/steam (g)

[Edited on 19-1-2017 by PHILOU Zrealone]

pennychem - 23-1-2017 at 08:26

Yeah, but I need some peracid for a baeyer villiger rxn,
i have tryed to add SPC to 80% AcOH and I think that
some per-acetic acid must be formed to oxidize my
substances , will it ? I think that the Sodiumacetate
only forms as some by product and that the major
part is peracetic acid.

PHILOU Zrealone - 23-1-2017 at 17:27

Quote: Originally posted by pennychem  
Yeah, but I need some peracid for a baeyer villiger rxn,
i have tryed to add SPC to 80% AcOH and I think that
some per-acetic acid must be formed to oxidize my
substances , will it ? I think that the Sodiumacetate
only forms as some by product and that the major
part is peracetic acid.

Of course you will get some PA acid if you have an exces of acetic acid.

2 Na2CO3.3 H2O2 --> 2 Na2CO3 + 3 H2O2
But
2 Na2CO3 + 4 HOAc --> 4 NaOAc + 2 CO2 + 2 H2O
So you dillute your reactants a bit because of the neutralization.

To reduce that anoying dilluting effect, it is common to use acetic acid anhydride (Ac2O) directly with the SPC (sodium percarbonate)

pennychem - 23-1-2017 at 18:50

ok , If I get this right, when add to the solution first the hydrogenperoxide
is given off and then when the peroxide has left the carbonate remains
reacts with acetic acid forming sodiumacetate ?

harderm - 23-1-2017 at 22:55

There's also sodium perborate, used in special mouthwashes. Might it be an alternative to the percarbonate? Apropo of nothing in particular, Na percarbonate is an ingredient of my bleaching toothpaste (Arm & Hammer brand).

PHILOU Zrealone - 24-1-2017 at 04:00

Quote: Originally posted by pennychem  
ok , If I get this right, when add to the solution first the hydrogenperoxide
is given off and then when the peroxide has left the carbonate remains
reacts with acetic acid forming sodiumacetate ?

Yes kind of. The H2O2 is held into the crystalline structure of the Na2CO3 just like water of crystallization would be.

In fact the carbonate anion reacts with the protons from the acid and shift the equilibrium H2CO3(aq) <--> H2O(l) + CO2(g) to the right...
You are then left with Na(+), Ac(-) (aqueous acetate) and H2O2.

When adding more HAc it may react with the surrounding H2O2 to afword the peracetic acid.

[Edited on 24-1-2017 by PHILOU Zrealone]