Sciencemadness Discussion Board

Formaldehyde odor

6dthjd1 - 11-9-2019 at 22:00

Hello

Does formaldehyde have any sort of a fishy odor?

Recently after heating paraformaldehyde from campa chem vigorously with no observable decomposition, I added some sodium hydroxide to water containing some sublimed portions of probable formaldehyde and witnessed a surge in temperature with the dissolution of the sublimate with the emission of a pungent fishy like odor.

Tsjerk - 11-9-2019 at 23:13

Are you sure you have paraformaldehyde and not hexamine?

Herr Haber - 12-9-2019 at 04:10

As Tsjerk, I think you have hexamine.
Paraformaldehyde definitely doesnt smell of fish but hexamine does.

Try burning some. If it burns easily with a blue flame then you have hexamine.

Boffis - 13-9-2019 at 07:12

Which country are you in? Paraformaldehyde is available as a fumigant in the UK from many farm stores and some local chemical suppliers.

unionised - 13-9-2019 at 15:45

Paraformaldehyde is a polymer of formaldehyde.
One of the things they use to catalyse the polymerisation is methylamine.
That certainly smells of fish.

6dthjd1 - 19-9-2019 at 18:51

@ Boffis

I am in the U.S.

@unionised How might methylamine get in there?

What uses might hexamine serve in RV toilet disinfectant? How might the manufacturers of this Campa-Chem product introduce hexamine in there?

draculic acid69 - 19-9-2019 at 23:02

Isn't that RV toilet treatment stuff paraformaldehyde solution and blue dye.why would they use hexamine? does it do what paraformaldehyde does?

Herr Haber - 20-9-2019 at 03:15

I have found 2 different formulations for that Campa Chem product. One right here on SM.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&...
And
https://www.centralstatesbus.com/wp-content/uploads/MSDS/The...

The second one looks more interesting.
You can find the "beginning" of an explanation looking up Bronopol:
https://en.wikipedia.org/wiki/Bronopol

But I suppose you found all that already.

6dthjd1 - 20-9-2019 at 09:48

My package mentions paraformaldehyde but not bronopol. I wonder if bronopol is habitually unlisted.

unionised - 20-9-2019 at 09:52

Quote: Originally posted by 6dthjd1  


@unionised How might methylamine get in there?


The manufacturers of paraformaldehyde add methylamine to formaldehyde to catalyse the polymerisation.
They don't bother to remove (all of) it.

ave369 - 24-9-2019 at 14:41

The smell of formaldehyde is stinging and very distinctive. I believe it is not possible to confuse it with fish or something.

Mabus - 16-10-2019 at 12:05

Yup. For some reason to me it feels like old furniture/bed with a tingling sensation. It feels familiar (I grow up surrounded by cheap communist stuff so I assume there were lots of formaldehyde-based plastics present) yet unique at the same time.