rocketman
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hydrogen peroxide.
Into 35% hydrogen peroxide, I poured in a bunch of Molecular Sieves For Water Removal in hopes of concentrating the peroxide. A fizzing began and a
white foam formed on the surface. Does anyone know what that white foam could be?
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Vomaturge
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If you're working with hydrogen peroxide, I'm sure you know that a bunch of different compounds can cause decomposition into oxygen and water or
steam. I suspect these particular. molecular sieves are one of them.
Why does the oxygen stay as a foam instead of escaping to the atmosphere? Perhaps the hydrogen peroxide has an impurity that helps it form bubbles, or
the molecular sieves are being broken down by bubbles forming internally, and releasing a sudsy compound into the former hydrogen peroxide.
I now have a YouTube channel. So far just electronics and basic High Voltage experimentation, but I'll hopefully have some chemistry videos soon. |
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itsallgoodjames
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Generally for concentrating hydrogen peroxide above 35%, vacuum distillation is used. This is quite dangerous though, as high test peroxide tends to
act similar to liquid oxygen, but at room temperature.
Nuclear physics is neat. It's a shame it's so regulated...
Now that I think about it, that's probably a good thing. Still annoying though.
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SWIM
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Some really old sources suggest drying in vacuum over concentrated sulfuric acid.
They claim you can get pure peroxide this way, but these are some mighty old sources, like 19th century formularies.(Maybe Dick's? Or the
Techno-chemical receipt book?)
They're also vague about how long this takes, and how hard a vacuum they use.
EDIT: Just noticed your name, and I'm guessing you'll probably want more volume and at a faster than this route would likely supply.
[Edited on 16-1-2021 by SWIM]
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Fyndium
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Mol sieves can act as a decomposing catalyst as per their porous structure and their consistent materials. It might be easier to state which stuff
does NOT react with H2O2.
"Decomposition is catalysed by various compounds, including most transition metals and their compounds (e.g. manganese dioxide (MnO2), silver, and
platinum).[34] Certain metal ions, such as Fe2+
or Ti3+
, can cause the decomposition to take a different path, with free radicals such as the hydroxyl radical (HO·) and hydroperoxyl (HOO·) being formed.
Non-metallic catalysts include potassium iodide, which reacts particularly rapidly and forms the basis of the elephant toothpaste demonstration."
What mechanism induces the explosive hazard of vacuum distilling H2O2? The stuff is used in 98%+ concentration as a rocket fuel and other
applications, and it is stated that the more concentrated it is, the more stable it is, due to water acting as an impurity. Apparently, this refers as
well to any impurity whatsoever, and more concentrated stuff of course reacts more intensely.
Certain it is that vacuum distillation can be carried out in a controllable manner that does not include explosions, as it is carried out in routine
in the industry. How, is the question. I would absolutely study this route, if I needed HTP.
It is apparent that many reactions can be carried out with peroxide compounds like percarbonate, perborate, persulfate, which are either otc cheap or
readily made from them, so it is always good to check out if it is needed for a specific purpose.
Not sure, actually, if H2O2 could be vacuum distilled off of a concentrated solution of sodium percarbonate as it is a mere adduct and leaves behind
sodium carbonate. It can be readily used to produce other of those, at least perborate.
[Edited on 16-1-2021 by Fyndium]
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symboom
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Here is some compiled information of hydrogen peroxide
Reaction and concentrating the peroxide.
I've had hydrogen peroxide decompose with silica gel and from activated carbon I think it has to do with neucleation sites of the material. I was
hoping I could make a solidified form of hydrogen peroxide.
http://www.sciencemadness.org/talk/viewthread.php?tid=156627
[Edited on 16-1-2021 by symboom]
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SWIM
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Great list of resources and information Symboom.
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