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Iodine from tincture

Migrated topic.

Grower

Rising Star
With iodine becoming more and more hard to get i thought i should get some before its too late.
So i got this iodine tincture that contained 5% iodine.
The bottle says 5% iodine and 10-30% nonionic surfactant(tensides).

I put some iodine tincture in a beaker and added 30% HCL with stirring.
I then added 3% hydrogen peroxide (H2O2).
No iodine crystals are forming.
Now, i am not a expert chemist but iodine should be precipitating out of the solution.
I have tried with more/less of both HCL and peroxide.

What happens is that after a while 2 layers are formed, one clear/yellow upper layer and one dark, deep red bottom layer.
The top layer probably is water,acid and other stuff and the bottom deep red layer is the iodine in some form.
Can the deep red layer be hydriodic acid?

This is so strange as i have seen this procedure done before and the iodine should be precipitate out and form on the bottom of the beaker.

Can the nonionic tensides interfere with the reaction somehow?
I also wonder if the deep red layer is hydriodic acid?
Anyone here can explain what happens (or at least should happen) chemically?

This method should be working and i have no idea why it isn't.
Anyone can help?

Grower
 
In my research why this isn't working i found the safety data-sheet for the specific iodine tincture.

I translate:

25% Iodine in tensidiodine. CAS-7553-56-2 No idea what they mean by this
(20% free iodine)

<20% Alkohole etoxilate C11. CAS-35398-01-1

<20% Acetetic acid. CAS-54-19-7 (product sheet says 7% acetetic acid)

1-5% Sodium iodide CAS-7681-82-5 (product sheet says 5% Iodine)

As i am not very good with chemistry, this doesn't tell me so much except of cause what it contains.
I still have no clue why the procedure doesn't work.
Maybe i should try find the safety data-sheet of other iodine tinctures that i know do work and compare them to see if the iodine is in some different form or something else that differentiate my tincture and one that works.
I really want to get this to work and also understand exactly what happens chemically.

Grower
 
Can it be that the alcohol content is interfering with the peroxide reaction?

I think i will try heating the deep red solution.
Maybe any alcohol will evaporate and maybe i get iodine vapors.
If so i can put an RBF with ice water on top of the beaker making the iodine deposit there at good purity.

This is just an idea, i am no chemist.
If this is a bad idea maybe someone can enlighten me.
I will use a small amount to try this.
 
So i got some breakthrough now.

When heating the deep red solution in a beaker some water vapor began to steam off.
After a while i could tell something else was evaporating but the fumes was still white as in the steam.
After a while again i could see a purlple tone in the vapors and i then put an ice/water filled round bottom flask ontop of the beaker.
The solution had now got way darker.
The purple vapors got thicker and i then turned off the heat due to the fact that i was inside under the kitchen fan.
I wasn't going to risk iodine vapor around my kitchen.
So this works.

I will preform this another day outside and maybe modify the procedure a bit so that the iodine vapors bubbles up through some ice cold water and deposits there.
This would work right?

The ice/water filled beaker do work but only a smaller amount will be gathered on the bottom of the flask and if i heat a larger amount i think the surface area of the RBF will be too small.

I don't understand why the HCL/H2O2 procedure didn't work but maybe it will if i heat the solution first boiling off some stuff interfering with the reaction.

I post update when i made more experiments.
I find it quite interesting experimenting with this stuff.
 
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