Sciencemadness Discussion Board

Formaldehyde Soln test.

Vosoryx - 13-1-2020 at 18:16

I am currently working on a long project about various synthesis of Methanal/formaldehyde from methanol. I have various methods to test and try, however all of them are low yielding without putting in work I don't want to do if I don't know they'll work. So what I'm asking is if anyone knows of any chemical tests for the presence of formaldehyde in a solution. At the low concentrations I am working with, doing it by scent is unreliable/innefective/possibly false. Anything you know of let me know.
Yes, I know that it's probably cheaper to buy formalin or paraformaldehyde. I don't care about price of my reaction. I'm doing this for research and fun.

Ozone - 13-1-2020 at 19:52

HPLC, physical: 2,4-dinitrophenylhydrazine in citrate buffer pH 4.5. yellow flocs result, characteristic MP, etc.

VIS: Chromotropic acid in Sulfuric acid.; probably done like this:

Fluorescence: Acetylacetone,

Titration: excess sodium sulfite and titration with sodium hydroxide to phenolphthalein endpoint.

Variation: Interesting, if I could get full-text:

And many others. I'd probably go with the chromotropic acid/sulfuric acid spot-test (if presence is all you need to know).


Vosoryx - 14-1-2020 at 12:15

Wonderful! Thank you so much O3! Much appreciated.

sclarenonz - 14-1-2020 at 12:21

you can build a small reactor put a magnifying glass to increase the sun's heat inside

then get the very red stones strong red color, crush it with potassium or calcium carbonete, throw urea and wait for the water to rise, after rising put to dry in the sun, then put inside the reactor and throw the gas in