Hydrogen peroxide concentration by freezing

[BetaTest]

Hi everyone!

 

I'm trying to make an at home tooth whitening gel that needs a final concentration of 6% hydrogen peroxide, when means I need a stock of 12%(1:2 dilution). My local drug store only sells 3% hydrogen peroxide. Now I know that I can buy 30-35% online very easily but the problem for me is it costs a lot. So I was reading another topic on this forum about people getting h2o2 to like 90% (not sure why) but they mentioned that you can get h2o2 to 62% by freezing. My question is how can I get 12-20% by freezing? I don't want it to get all the way up to 60% and I'm also not clear on the method (just place it in the freezer and take out the ice cubes?). Also after I'm done with the freezing concentration, how do I estimate the final concentration?

 

thanks to everyone who read this, any advice would be appreciated!

[Fabrizzio2010]

I'm also trying to get mine to atleast 20% for more potency. I'm not sure how though, I don't want to get it up 90% because that just seems too strong. I'm making oxygen for a special experiment at home. Do you know where I can get Manganese Dioxide in quantity? I'm sick of cutting these batteries open.

[Marat]

You can buy 20% potency over-the-counter in a lot of European pharmacies. Not sure where you live, though.

[Techman588]

I have never heard of concentrating H2)2 by freezing. The only method I have even heard mentioned is by distilation and that takes some special equipment to do and do safe. Reasons to have hydrogen peroxide in concentrations of 75% to 90% include use as a propellant in rocket engines, some use a solid fuel and oxidize it with high percentage strength H2o2, another rocket motor is where H202 is decomposed rapidly (read explosively) in a chamber on Silver mesh screens into high pressure steam then directed through a nozzel to get thrust. An example of the first was a land speed record car with the miss Budwiser title they used HDPE as the fuel, they set a record dont know if its still held or not, the second type has been used in the Bell Rocket belt famous in several films. If you need a source of H2O2 of less than 30% strength its available in most areas over the counter in of all places BEauty Supply outlets (Amazing what folks will put on thier hair aint it?) as 20,30 and 40 Volume strength CLEAR Developer, be aware the cream type developer wont work. Some Supply outlets are for "pros" only if you find this just get a hairdresser to get it for you, stuff is cheap a quart bottle is less than 5 bucks and there is no hassle with shipping when you pick it up. Hope this is helpful. Be carefull the 20 volume is strong enough to slightly burn your skin!!

[Enthalpy]

Guys, peroxide is dangerous.

 

At 20% concentration it's bad for your skin. At 70% concentration it's a brutal explosive, quite unpredictable, and it lights most materials like gloves and clothes.

 

Do NOT concentrate it by distillation, as you're likely to let it detonate.

 

People telling "90% by freezing" didn't try by themselves. There is a eutectic that prevents reaching this concentration.

[Suxamethonium]

They want 6% which isn't inherently explosive or irritating. Usually this is readily available as per the 3%, you may need to 'shop around' to find a specific company/branch that stocks it however. Personally, if you are using it for your teeth I would find a brand suited for oral use (e.g. Hydrogen peroxide 6% BP) probably from the chemist

 

If you must use 12%, I think there is a version that is 15% BP. Not sure how readily available it is- but it can easily be diluted to required concentrations.

Edited July 20, 2012 by Suxamethonium

[Zebramama]

Hit Sally Beauty.  They sell to the public, and have up to 40 volume CLEAR developer readily available to the public.  It's about $4-5 for 32 oz. From 10 volume(3%) to 40volume(12%) in sizes starting at 2 oz up to gallon sized jugs.  They also sell a cream version of each 9f the developer strengths, but you don't want that. It's got extra conditioners and thickeners in it to facilitate blending with bleach powders or tube gel hair colorants.  The things we women will subject ourselves to for the sake of beauty, huh? 😜