Sciencemadness Discussion Board

How to make 30% hydrogen peroxide?

Booze - 21-3-2017 at 08:35

Hello. I am interested in creating 30% hydrogen peroxide for some copper chloride synthesis I plan on making, or for other stuff as well.

But how would I go about turning my 3% peroxide to 30%? Could I distill the mixture until the temperature goes above the boiling point of water, or even simpler, boil it in open air until 300 mL goes down to 30?

I don't think I can freeze dry it, because its melting point is almost the same as waters.

Thanks.

XeonTheMGPony - 21-3-2017 at 08:52

easiest method is go to a hippy shop (Natural/health food store) most sell 30 to 35% peroxide for some reason with those types it is usually "magic" Here it costs 15bucks for a 1L bottle at 35% Less if I reuse the bottle!

Second method (Painful slow) is 3% and dehydrate it by warming to 70 apx degrees and let evaporate can go up to 90c if I recall but I like to keep it cool as possible.

Freezing it method can work for the first stage, freeze it, then support it upside down over a container then slowly let it warm then stop once it is to what ever temp all the h2o2 would be all melted, then evaporate the collected mass down further?

[Edited on 21-3-2017 by XeonTheMGPony]

[Edited on 21-3-2017 by XeonTheMGPony]

JJay - 21-3-2017 at 08:53

You can actually evaporate off the water if you are very careful to exclude contaminants.

https://www.youtube.com/watch?v=xvYeefmbmZI

I've been thinking about trying to concentrate some 30% to 50%.

Metacelsus - 21-3-2017 at 09:30

If you're just trying to make copper chloride, you don't need 30% hydrogen peroxide (although I don't know about the "other stuff" you mentioned).

Boiling will decompose the peroxide. Use mild heat, and blow air over the solution to speed evaporation.

Booze - 21-3-2017 at 09:36

I know, I have made it before with both 3 and 30 hydrogen peroxide. But the 30 percent goes much faster then 3 percent. I could also use it for the easy elephant toothpaste and make super foam.

Amos - 21-3-2017 at 12:50

If you have a beauty store in town you can go to (SallyBeauty in the US is everywhere and almost always carries it), they have "clear developer" for hair dying and bleaching; the 40-volume kind is about 12% H2O2, maybe $4-5 per liter.

[Edited on 3-21-2017 by Amos]

Melgar - 21-3-2017 at 15:46

I got a gallon of 30% H2O2 from a local beauty supply place for $8.99. It looked like it'd been sitting on the shelf for a while, and there was only one gallon left. It does seem a bit weaker than regular 30%, but for the price I can't complain.

AJKOER - 21-3-2017 at 16:22

A path I have as of yet not fully explored, would be to start by preparing a metal peroxide, like CaO2 or MgO2 from lots of cheap dilute H2O2 acting on Ca(OH)2 or Mg(OH)2.

Unfortunately, my experience with the latter salts is that there are always, while in cold solutions, bubbling releasing oxygen.

If one could rapidly remove water to form the dry or near dry salts, that could be a starting point to add an acid source thereby creating a higher strength H2O2. For example, with H2SO4:

CaO2 + H2SO4 ---> CaSO4 (s) + H2O2

One might think that the acid gas CO2 would work here, but unfortunately, CO2/HCO3- establishes an equilibrium reaction with H2O2, effectively losing some hydrogen peroxide, as CO2 can further react, I suspect, with formed H2CO4 thereby permanently removing it (those not believing, add Na2CO3 to acidic H2O2 and treat with a given excess quantity of NaOCl, liberating O2 collected over water dissolving any CO2. Repeat absence the Na2CO3/CO2 and observe more O2 evolution!).

Interestingly, rather than a lot of boiling, this path is cool:cool:

[Edited on 22-3-2017 by AJKOER]

A Halogenated Substance - 21-3-2017 at 16:30

In relation to AJKOER's post above, there is a post on Chemsynth as a guideline for this:

H2O2 from BaO2: http://www.prepchem.com/synthesis-of-hydrogen-peroxide/

Additionally, here's another guide on producing such peroxides, though it also lists how to produce relatively water free peroxide from barium nitrate as well:

http://www.prepchem.com/synthesis-of-barium-peroxide/

Edit: Removed some unnecessary space making the post large

[Edited on 3-22-2017 by A Halogenated Substance]

Liamatpm - 22-3-2017 at 09:43

You could definitely distill the Hydrogen Peroxide but you don't want to heat it up to much and you want the container to be extremely clean. Because if not the hydrogen peroxide will just break down in to H2O and a oxygen molecule.

Booze - 22-3-2017 at 09:58

Quote: Originally posted by Liamatpm  
You could definitely distill the Hydrogen Peroxide but you don't want to heat it up to much and you want the container to be extremely clean. Because if not the hydrogen peroxide will just break down in to H2O and a oxygen molecule.


What temperature does h2o2 decompose at? My hotplate is really crappy and unpredictable, and I can't use my bunsen burner won't be acceptable to use for obvious reasons.

Geocachmaster - 22-3-2017 at 12:12

You should not attempt to distill hydrogen peroxide under normal conditions because it decomposes at its boiling point. H2O2 should only be distilled under reduced pressure so there is no decomposition, which can happen explosively fast according to Wikipedia (which I don't doubt). I would recommend that you not try under reduced pressure either, because any contaminants will cause rapid decomposition of the hot concentrated peroxide.

The best method for you would be evaporation. Fill a (very) clean beaker which is the least scratched possible with diluted hydrogen peroxide. Heat gently to keep in the 65-75 C range and let it evaporate until the desired volume is reached (for example a 10x smaller volume if starting with 3% and going to 30%). Zhmapper, aka old Doug's Lab, aka Praxichys, has a good video on this: https://youtu.be/xvYeefmbmZI

I bought 1L 29% H2O2 for $15, meant for plants I think. Although more expensive, it's not too bad a deal IMHO if the effort of evaporating is not worth it.

Liamatpm - 22-3-2017 at 16:03

I would like to add something but Geocachmaster said all that you need to know. Just remember: don't get to the boiling point.

PirateDocBrown - 22-3-2017 at 16:59

Pool and spa supply stores sell ~30% H2O2, often by the gallon.

bluamine - 22-3-2017 at 22:19

I have the same problem, actually I have only access to 3% peroxide solution.
Anyway, if you want to concentrate the solution you can just freeze it instead of boiling it
Guys, I have two ideas may work well if we use them together: UV light & an ozone generator! What do you think about it?


[Edited on 23-3-2017 by bluamine]

symboom - 15-6-2017 at 19:29

I think I figured out a method that might work to form ectreamly concentrated hydrogen peroxide so many people know that urea forms an adduct with hydrogen peroxide
And urea citrate is supposedly insoluble and not destructive to hydrogen peroxide

Urea/peroxide adduct
Add citric acid form
Hydrogen peroxide and urea citrate percipitate

Acually what you are describing is my first procedure hydrogen peroxide has the water distilled under reduced pressure I at it to get to around 80 to 90 percent which past 72 I read some where that hydrogen peroxide vapors are explosive it makes me think of chlorine dioxide except that is light sensitive I also kinda want to see what that looks like or how that behaves the vapor would have to touch a catalysis.

Not my use for it but an interesting observation that would be.

No base is needed just urea hydrogen peroxide and citric acid
The citric acid is to remove the urea

Urea peroxide and citric acid is a solid and water is added to leach out the peroxide and drive to precipitation reaction of urea citrate

Not sure if this could work in absolute ethanol without reacting
Ethanol has a lower boiling point the pure hydrogen peroxide

This is my theory now where did I put my citric acid.



[Edited on 16-6-2017 by symboom]

alking - 16-6-2017 at 07:29

The easiest, fastest, and probably most practical way for the average member here would be to concentrate it under reduced pressure. You should have little if any decomposition that way and you can do so at RT, or below, with any decent vacuum source. I'm not sure if there's a risk of explosion after a certain concentration though, I wouldn't go past 50% w/o verifying that, but you likely don't want to anyway.

How do you plan to go from a H2O2 urea citrate adduct to a pure 30% solution though? Yeah, you've concentrated the H2O2 by removing the water, but you now need to add water back, basify, then remove the base/urea/cirate to obtain the desired product. There are numerous ways, but they don't seem anymore practical to me than simply boiling down the 3% from the start and you're likely then going to have some hydroxide or salt contaminant left in the final solution, albeit minor.