paulll
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Iodine from tincture
I'm trying to drop Iodine from tincture and not having much luck.
So this evening I charged a beaker with 100ml of tincture of Iodine(2.5%), added 40ml Muriatic (ie, technical grade conc. HCl), which gave off a bit
of vapour and a mild exotherm. Threw in 120ml of 3% H2O2, gave it a swirl and let it be for a few hours.
Zero precipitate.
Going back in my lab book, I did the same thing, with Iodine tincture from a different vendor, H202 from a different vendor, and a different stock of
Muriatic from the same vendor, in a 1:1:1 ratio, on 11 Jan, same result; Zero precipitate.
The glass is clean (pristine on the first try), everything's at room temp.
I'm looking at a 500ml beaker filled with what looks like dilute tincture of Iodine, there might be vague bits of floaty precipitate near the bottom,
but there certainly is not any collectible Iodine at the bottom.
I assume I'm making an obvious fuck-up here, I'd be much obliged if someone would point it out.
Cheers
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Sulaiman
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Is it definitely "iodine tincture" https://en.wikipedia.org/wiki/Tincture_of_iodine
or is it "Povidone-iodine" https://en.wikipedia.org/wiki/Povidone-iodine
If its povidone then I've seen relevant threads here on SM
https://www.google.com/search?q=site%3Asciencemadness.org+po...
not tried myself.
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Triflic Acid
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If you want iodine, try to start with iodide salts, much better. But, no matter which method you choose, if you try to make anhydrous iodine by drying
it with sulfuric acid, make sure that you precool the wet iodine and the acid. Half of my iodine sublimated away because I added rt acid to the iodine
and the temperature jumped. But it did produce some nice purple iodine fumes 
[Edited on 24-6-2021 by Triflic Acid]
There wasn't a fire, we just had an uncontrolled rapid oxidation event at the power plant.
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paulll
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Definitely tincture: Alcohol, water, 25mg/ml Iodine, 19mg/ml KI.
Triflic Acid, I might do that but I'd rather do it with stuff I can buy down the street than with stuff I'd be ordering from Poland and waiting 3
weeks for - and I've little reason to suspect that that wouldn't go just as wrong as the last two runs.
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arkoma
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I2 from KI is a breeze.
"We believe the knowledge and cultural heritage of mankind should be accessible to all people around the world, regardless of their wealth, social
status, nationality, citizenship, etc" z-lib
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Triflic Acid
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I don't see why you need to order from poland, a decent supplements store might sell it as an iodide supplement.
There wasn't a fire, we just had an uncontrolled rapid oxidation event at the power plant.
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paulll
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It's a breeze to get it from tincture, too, but here I am :p
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Keras
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As far as I know, iodine tincture is just iodine dissolved in alcohol. Why don’t you just try to heat it and collect sublimed iodine?
That being said, as the others remarked, it’s not a very efficient way to get iodine.
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Sulaiman
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I think that I'd try bubbling chlorine through the solution,
(e.g. TCCA + HCl)
should be able to get a good yield I think,
if you are comfortable with the chlorine gas.
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MidLifeChemist
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What you are trying works for potassium iodide, not iodine dissolved in alcohol afaik.
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draculic acid69
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Perhaps the alcohol is causing the problem.
Anyways here is a possibly different approach:
Take tincture and add NaOH solution to tincture
forming sodium iodide and iodate or hypoiodite
or whatever it is then evaporate off the alcohol
leaving a basic clear(should be clear after the naoh
bonded with the free iodine) solution of water+iodide salts
which can be acidified and oxidised to free iodine in
a (probably) cleaner and higher yeilding way.
No alcohol should mean better precipitation.
After saying all that I should point out that
If you are going to try this variation U might as well just start with povidone iodine solution and proceed as the following Video shows:
https://m.youtube.com/watch?v=FNf8PSda7iI
Or this one:
https://m.youtube.com/watch?v=VeQ_BDWm7ls
Povidone iodine can be bought cheaper and in larger amounts than the tincture.
[Edited on 28-6-2021 by draculic acid69]
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paulll
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Quote: Originally posted by Sulaiman  | I think that I'd try bubbling chlorine through the solution,
(e.g. TCCA + HCl)
should be able to get a good yield I think,
if you are comfortable with the chlorine gas. |
I still have the solution, I think I'll try this before I waste it.
| Quote: | | If you are going to try this variation U might as well just start with povidone iodine solution |
I had considered that but with povidone being thin on the ground right now (there's an empty spot for it on the shelf at every local pharmacy, has
been for months)I thought I'd have a go at the tincture - which *looked* a shade more straightforward anyway. I think I'll be keeping an eye out for
povidone and going down that route.
Thanks for the feedback, everyone.
[Edited on 28-6-2021 by paulll]
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S.C. Wack
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recovery of iodine from residues
| Quote: Originally posted by draculic acid69 | Perhaps the alcohol is causing the problem.
Anyways here is a possibly different approach:
Take tincture and add NaOH solution to tincture |
Great idea...if one wants to make iodoform.
Sounds like a lot of HCl. And H2O2...but I didn't do the math...it's mentioned as I suspect that chlorine reacts with iodine, and alcohol. This may
interest someone:
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paulll
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Interesting read, S.C., where's that from?
Anyway I blew a couple of moles of Chlorine through it (which was interesting, I'm getting to working outside as much as possible and the mosquitoes
were insane this evening; but there weren't many of them near the apparatus so I gassed myself *again* but this time it was by conscious choice), but
the mixture didn't care one iota. I'm going to waste this one, chalk it up to,"you know there's no such thing as the easy way," and keep an eye out
for povidone while I contemplate buying a bunch of KI. (Triflic: I'm finding chems to be more-and-more sparse on eBay and there's not much for local
vendors so I'm resigning myself to the idea that it's easier if I just use onyxmet as my default supplier of dry chems).
Also, MidLifeChemist, you may have a point; I've read tons about precipitating Iodine this way, haven't seen much about actually *collecting* it this
way, maybe the EtOH is the embuggerance and it's actually not a practicable route at all.
Thanks again for your input, folks.
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unionised
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I'd be tempted to add a reducing agent- steel wool, bisulphite- whatever- until the iodine was all reduced to iodide.
Evaporate off the water and alcohol.
Then dissolve the residue in a small volume of dilute HCl (or dilute H2SO4 or H3PO4) and then add the peroxide slowly.
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