mauricethegangsteroflove
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Mood: The cat is in charge here.
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Formaldehyde synthesis
I would like to try synthesizing some formaldehyde so I can try synthesizing some Bakelite and maybe hexamine. A brief search of this forum found that
potassium peroxymonosulfate, sold as non-chlorine pool shock, is known to oxidize methanol to formaldehyde.
I've got about 100ml of methanol in a flask with a few grams of potassium peroxymonosulfate and intend to try gently heating it and bubbling the gas
that comes off through some water. I'm picturing running a rubber tube down into the bottom of a volumetric cylinder with some cotton in the end to
break up the bubbles, maybe with a funnel as a suckback trap.
Has anyone tried anything like this? I haven't seen anything regarding this method, and would appreciate any advice, comments, or "dear God don't do
that you idiot" warnings you might have.
Also curious what is happening at the chemical level, if anyone has studied the reaction much, so I can try doing some stoichiometry to optimize this.
"I wonder what this stuff tastes like"
-- Last words of Johnny the chemist
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Alkoholvergiftung
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Hexamin could alternativly made with Dichlormethan and alcoholic ammoniasolution in an autoclaven. Temperature over 90C and under 120C. The problem
here is the Hardware but you can buy Dichlormethan as an solvent.
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mauricethegangsteroflove
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I don't have an autoclave but that does sound interesting. I will try it if and when I have the means to do so.
I have been speculating about a few ways to do the process I'm attempting, and I think it might work better to just let the KHSO5/Methanol solution
sit for a few days, then crash out the paraformaldehyde in some water. I can drop that in some distilled water and just heat and stir it, maybe with a
bit of NaOH, and make formaldehyde that way. I think this is probably the best method, and I'm going to try that.
A possible but probably bad alternative (which I will not be trying) to go straight to hexamine might be to just pour some ammonia solution into the
flask where the formaldehyde is forming and to boil that off, but I think there will be excess KHS05 in there and I really don't like the idea of
boiling down a mix of hexamine and a strong oxidizer like that.
"I wonder what this stuff tastes like"
-- Last words of Johnny the chemist
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Alkoholvergiftung
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The only lab methode for Formaldehyd i ve read was oxydation of methanol with mno2 and H2SO4 it forms methylal with an boiling point around 45C that
methylal was than heated with 2 parts concentrated sulfuric acid to form formaldehyd. Why this two steps i dont know.
Alternative for methanol to formaldehyd is the catalityc way. Intersting is the Tollens, Trillat , Cambier and Brochet Lamps every one of them made
indipendent an desinfection lamp, like and ethanol lamp the wick transports the methnol to an platin wirenet and there it got oxydizes to formaldehyd
ive read they could make 5kg formaldehyd per day. Yield was crapy only 25% but if someone use silver instead it might be higher. And if someone can
find drawings of this lamps.
Methylal = C3H3O2 Methylendimethylether. bp. 42C was used for anesthesia
[Edited on 28-3-2026 by Alkoholvergiftung]
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0_Q
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look at the data, catalyst K seems to be most yielding and most selective.
they use around 500°C and the catalyst is fairly easy to make.
but they state in the claims they make this in the absence of oxygen.. so heh
Attachment: formaldehyde from meoh via ZnO cat.pdf (569kB)
This file has been downloaded 3 times
[Edited on 28-3-2026 by 0_Q]
also, wouldnt a reflux with active MnO2 do the trick ? - to some extent
[Edited on 28-3-2026 by 0_Q]
also i would look into photocatalystic methods to avoid mean reaction conditions
[Edited on 28-3-2026 by 0_Q]
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leau
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More articles on formaldehyde are in the attached archive 
Attachment: FormaldehydeDocs.zip (6.4MB)
This file has been downloaded 8 times
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