Sciencemadness Discussion Board

Acetone in chloroform

Eisenpanzer432 - 9-2-2018 at 10:38

I made a small amount of chloroform from bleach and acetone, and am trying to test for acetone contamination. I read that Nessler’s reagent reacts with acetone, but I don’t know if a catalyst is required. I observed no rxn between acetone and Nessler’s. The chloroform (stabilized w/ a small amount of methanol) reacted with Nessler's. Chloroform mixed with acetone did not react with Nessler’s can anyone give advice on this?

aga - 9-2-2018 at 10:40

There will still be bleach, water, acetone and salt in there, as well as whatever else was in the original bleach (perfume, surfactant etc).

Best to just distill it to make clean chloroform.

JJay - 9-2-2018 at 10:46

Distillation won't remove acetone easily; shake chloroform with saturated sodium bisulfite solution to remove the acetone and then with dry potassium carbonate to remove traces of water and sulfur dioxide, then distill.

aga - 9-2-2018 at 12:52

Didn't know that. Nice one.

Eisenpanzer432 - 10-2-2018 at 12:23

Thanks JJay. I followed Nile Red’s procedure from youtube for synthesis, but without testing the bleach concentration. I assumed 0.9 times the stated value on the label to make sure there would be an excess of bleach. I still haven’t found the paper again where I read about Nessler’s rxn w/ acetone. It was from the 30s I think.

JJay - 10-2-2018 at 13:00

If you have sodium bisulfite, it's better to use an excess of acetone because bleach is expensive. I once did the same thing, using an excess of bleach, and there was still some acetone in the product.

[Edited on 10-2-2018 by JJay]

Eisenpanzer432 - 16-2-2020 at 22:56

https://www.jbc.org/content/119/2/663.full.pdf
This is what I was trying to reference over a year ago.

UC235 - 17-2-2020 at 07:29

Just wash it with concentrated sulfuric acid if you want to be sure.