Sciencemadness Discussion Board

Getting the sulfur smell out of glassware and reagent bottles

SuperOxide - 10-11-2020 at 08:53

A while back I was recrystallizing sulfur using xylenes, and I didn't want to dispose of the xylene solution containing the residual because I could use that for the next time I need to recrystallize sulfur. I kept it in a Pyrex 500mL GL45 capped bottle. However, I now needed that reagent bottle for something else, so I xfered the xylene/sulfur solution to a diff bottle, but now that damn smell of sulfur won't seem to go away.

I rinsed it with some xylene, then washed it with hot water and soap, and let the whole thing soak even. I removed the clear plastic ring thing from the lip thinking maybe the smell was from sulfur particles trapped in that and re-washed everything, let it air-dry for 4 days... but that damn smell won't go away :mad:

Anyone have any tips for getting the smell of sulfur out? This seems like a rather petty thing to have to ask for help on, so I apologize for that. Usually the chemicals I work with (as a noob) aren't this difficult to clean up.

Thanks in advance for any advice.

macckone - 10-11-2020 at 09:48

Use a strong oxidant after triple rinsing with acetone (removes other organics) then water (removes the acetone), so 6 rinses.
Bleach is probably the best bet, use it straight and fully submerge and soak the vessel.

Sulfur is not that soluble even in hot xylene, toluene is better.
An oxidant will convert sulfur and any sulfides or mercaptans (which really smell and probably what you are dealing with) to sulfuric acid and carbon dioxide.
You need to use a triple treatment method, possibly even four or five to reduce it below the odor threshold which is 2 PPB or less for mercaptans.
In bleach the sulfuric acid will be converted to sodium sulfate.

A side note xylene will react with the sulfur releasing hydrogen sulfide and forming all kinds of nasty side products.
The same will happen with toluene but at a much slower rate.
From a purification perspective, the side products are left in the xylene or toluene so they aren't important.
From a storage standpoint they can lead to the problem you currently have.


SuperOxide - 10-11-2020 at 11:43

Quote: Originally posted by macckone  
Use a strong oxidant after triple rinsing with acetone (removes other organics) then water (removes the acetone), so 6 rinses.
Bleach is probably the best bet, use it straight and fully submerge and soak the vessel.

Sulfur is not that soluble even in hot xylene, toluene is better.
An oxidant will convert sulfur and any sulfides or mercaptans (which really smell and probably what you are dealing with) to sulfuric acid and carbon dioxide.
You need to use a triple treatment method, possibly even four or five to reduce it below the odor threshold which is 2 PPB or less for mercaptans.
In bleach the sulfuric acid will be converted to sodium sulfate.

Thank you! I will give that a go.
Quote: Originally posted by macckone  
A side note xylene will react with the sulfur releasing hydrogen sulfide and forming all kinds of nasty side products.
The same will happen with toluene but at a much slower rate.
From a purification perspective, the side products are left in the xylene or toluene so they aren't important.
From a storage standpoint they can lead to the problem you currently have.

Interesting - So perhaps I shouldn't keep the xylene/sulfur mixture if I don't plan on using it within a reasonable timeframe? Good to know. I'll get rid of it (I don't plan on using it for a while anyways).

symboom - 11-11-2020 at 07:48

I read somewhere that acetic acid can dissolve sulfur

I'll see if I can find the link

I'd say hydrogen peroxide or bleach is very good at removing sulfur smell

[Edited on 11-11-2020 by symboom]

Fyndium - 11-11-2020 at 09:52

I recrystallized a sulfur compound from toluene once and when I recovered the toluene by redistillation, the foul stench never went away.

Dr.Bob - 11-11-2020 at 12:55

Household bleach works well on most sulfur smells. You should be able to stir the toluene with it and then separate it and recover most. And wash your glassware in it. I don;t think hydrogen peroxide is a strong enough oxidant, but it might work in some cases.

Fyndium - 11-11-2020 at 13:20

That's interesting and clever, actually. Toluene's practical insolubility makes washing it trivial with any water-based stuff and if it removed the absolute stench, it allows much more comfortable reuse of it. It's a good recrystallizing solvent, but some sulfur compounds just reek the hell out of any person. Hell, my fume hood actually still has occasional hints of that synthesis even it's almost 2 months.

I'm always vary of distilling stuff that's made with strong oxidizers, nitrates, peroxides or chlorites because of fear of explosion hazard. Even when I never ever distill anything to dryness, for very few singular exceptions.

macckone - 11-11-2020 at 21:23

Yes, toluene and xylene need a phase transfer catalyst to be oxidized by hypochlorite.
A lot of mercaptans have substantial solubility in water.
And mercaptans are oxidized by hypochlorite.
Interestingly toluene can be converted to benzaldehyde with hypochlorite and a phase transfer catalyst.
No clue why it doesn't proceed to benzoic acid but it apparently gives a high yield.

pneumatician - 10-1-2021 at 14:17

Put water full, rest some days, remove and repeat, 3 or 4 times and the smell is removed.

SuperOxide - 10-1-2021 at 15:18

Quote: Originally posted by pneumatician  
Put water full, rest some days, remove and repeat, 3 or 4 times and the smell is removed.

I actually did try that, and I could still smell it a bit. The bleach worked a charm, I just didn't try that before because I didn't have any on hand and most places I went at for a while were out due to pandemic (though I did try that COMET powder stuff, which says it has bleach, and it didn't work as well as I expected).
I went out and got some regular ol bleach as suggested, and stores had restocked :D (it was a little while since I went looking for some).

pneumatician - 10-1-2021 at 15:32

with bleach maybe you change sulfur by bleach smell :)

SuperOxide - 11-1-2021 at 10:10

Quote: Originally posted by pneumatician  
with bleach maybe you change sulfur by bleach smell :)

Which is fine... since that kinda goes away on its own, lol.

macckone - 11-1-2021 at 10:45

Sulfur is readily oxidizable. Adding bleach converts it to sodium sulfate if you use enough
The mercaptans are the real issue, they wreak. But they are also readily oxidized by bleach.
Oxidizing lower mercaptans in a basic solution (aka bleach) converts them to sodium sulfate and sodium acetate and such.
All of which have much less smell than mercaptans.
If toluene is the primary thing that was converted to mercaptan (benzyl thiol) then you wind up with sodium benzoate.

TriiodideFrog - 12-1-2021 at 04:56

You can pour some carbon disulfide into the bottle and let it soak inside.