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Author: Subject: Finally! Povidone iodine extraction (this one works way better than Rhodiums extraction method)
_navarone_
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[*] posted on 16-4-2004 at 19:50
Finally! Povidone iodine extraction (this one works way better than Rhodiums extraction method)


OK guys.
Im happy you accepted to give me another chance and i just wanted to say thanks first.
Well...to thank you guys back i want to share what i learned in my period of absence from this forum.
Something that has been complicating chemists and meth makers life, is the damn extraction of iodine from the most available source. povidone iodine.
The problem is that povidone traps iodine really strongly by a charge bonding.
povidone was designed to trap the iodine and not let it sublimate at room temperature so that people who would like forget to close the lid of the container wouldnt find the solution totally iodine free after a few minutes. Another use of povidone is to increase the solubility of iodine.
As we all know iodine is not that soluble in water but if you notes, in tinctures like betadine there is 10mg of i2 per ml.
Now how is that possible?
sice povidone is very soluble in water, the iodine attracted by it will also dissolve like sugar. So the tincture doesnt need alcohol to dissolve the iodine...it can be dissolved in common water.
now heres a pic. of the povidone iodine molecule:




So here u can see that iodine is not bonded to the povidone but its just held by some kind of charge.
Heat is the solution to free the i2 from the evil povidone.
now i know you are gonna say that there is already a method of povidone iodine extraction on Rhodium.ws.
I read it......and all i can say is that it sucks.
It sais:

1) boil your liquid to absolute dryness
2) put the dry povidone i2 in an erlenmeyer and set up a coldfinger apparatus
3)add heat and the iodine will sublimize from the povidone.

WRONG! WRONG! WRONG!

Ive been studying this extraction for pretty long so i will highlight the errors:

By boiling the tincture you will just let about 40% of the iodine to sublimize away and spread into your house.

The iodine that will sublimize from the dry liquid will be just something like 20%.

Trust me,i tried this method many times.

The sublimation tecnique is right but its not done in the right way.
So after lots of practice...i finally solved the maxi problem.
The equipment ur gonna need is:

1)liebig condenser
2)quickfit erlenmeyer(a big one)
3)hot plate or heat source

In the method that i will describe sonn there will be no need to dry the tincture.
ok heres an image of the setup:




The secret is H20 and a thin layer

the water will help iodine escaping from the povidone since iodine gets trapped immediately when it touches the povidone.
the water will keep a certain distance between the povidone molecules.
the thin layer also helps the sublimation.
I tried this experiment before with the erlemeyer half full and it didnt work that well.

I suggest to put more water than tincure for a better sublimation. But the thin layer must not exeed 1cm.

it is reccomended a big erlenmeyer to extract more tincure at the time.
I first started with a 100ml erlenmeyer and i had to extract 30mg at the time since the diameter of the erlenmeyer was so small.

Once the setup is complete just turn the heat to 300-400c' and u will start to see the iodine sublimating.
After one minute you will see a really pretty purple cloud inside the erlenmeyer and some cristals growing inside the liebig condenser.
Alot of water will come trough but it will condnse and drip back to the container.
boil the mixture until you cant see any purple gas anymore.
For a final check, see the color of your mixture.
Dont look it from the top but from the side.
he mixture should be pale pale yellow.
What does that mean my friend?
finally the iodine said goodbye to the povidone.
:D :D :D

When all the iodine has sublimated, turn off the heating pad and trow away the povidone H20 mixture.(watch out! the erlenmeyer is gonna be hot!)

Dont u even dare putting some more tincture inside the mixture since the povidone concentration will be soo strong and the iodine will never sublimate away.

Pour the mixture off, clean the erlenmeyer and get ready for the next extraction.
You will be able to extract like a little at the time depends on the diameter of the erlenmeyer. bigger is the diameter, more tinc u can add to that 1cm layer.

After a few extractions, ur condenser will be "full" of iodine crystals sublimated on inside walls.

Now all you gotta do is to take it out, and thats a bit tricky but u can build a "pusher".

What i did worked well. You gotta need:

1)a testube cork(rubber)
2) a thin stick longer than the condenser

Calculate the diameter of the iniside walls of the condenser and cut a piece of the testube cork with a diameter slightly bigger than the walls.
Then spike the rubber piece to the long stick.

Thats gonna be perfect to push out the iodine.

Now u understand why a liebig and not an ahlin condenser must be used.
Its a bit tricky pushing the crystals out from an ahlin condenser.

A few more precautions for the pushing out of the iodine.
Put ur condenser upsidedown with a watch glass on the bottom.
push the iodine from the top and slowly since it will pop away easely and not flow down like cream.

Well...shit! this extraction method kiks ass.
From a 1 liter tincture with 10mg i2 for ml...i extracted a bit more than 9 grams.
Thats more than 90% of the total iodine inside the tincture. And then a povidone tincture bottle doesnt cost that much either.

Now i know that a cold finget could be used instead....but the problems are:

The coldfinger will cool down the erlenmeyer and make the iodine sublimize inside the walls of the erlenmeyer.
The coldfinger will be too close to the boiling liquid and there might be a fuck up!

Well finally! the problem is solved!
after many readings of hard work with failed extraction...the method was pretty easy at the end.

I hope this method will be useful to you guys. i cant wait to give this method to The-Hive. Im sure much more people will be happier there than here..lol!:D

peace

from >>-Navarone->

-The End-

[Edited on 18-4-2004 by _navarone_]




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[*] posted on 17-4-2004 at 00:45


Amazing method!!:DWell, i can try this soon enough..



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[*] posted on 17-4-2004 at 08:17


Nice to see you contributing.

Is Iodine made from povidone that cheaper than iodine made from KI?




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[*] posted on 17-4-2004 at 09:10
Dunno!


I dont know.

Where i live, betadine is the only iodine tinc available.

i dont think povidone is that difficult to make in labs.

The advantage of povi I2 is that it can be dissolved in high concentration inside water.

Have u notesed that the liquid is black.
Povidone is a white crystal so the black is the iodine and to make the water that dark it need a lot of iodine.
10mg for ml

Ki and I2 tinctures are dissolved in alcohol.
and i dont think KI is that soluble in alcohol.
Povidone iodine industries dont have to use alcohol for the tincture so that makes the tincture cheaper i think.

oh...wait a second ill go and check.
......

Hmmm i went on an italian Drugstore website:

http://www.farmaplanet.it/farmacoviewadv.asp?Nome=&Minsan=&d...

Well.....even if nobody(or maybe someone) hee speaks italian,u can see
that a 100ml solution of alcohol with I2(iodio) and KI (ioduo di potassio) costs
5.89 euros.

A 125 ml solution of betadine costs
7.90 euros.

Im sure betadine has more iodine than the other alcohol solutions.

Betadine has a 10% of iodine in itself.
The other alcohol solutions ive read about have from 2% to 7%.
So yeah...in proportions of iodine, povidone iodine solutions are cheaper.
And i think the extraction of iodine from povidone is easier then converting KI to I2 and then sublimize it.

I wanna make a correction to the extraction post i just writed down.

The percentage of water should be higher(70%) for an easier extraction.
But remember..the layer must not be higher than 1cm or the iodine will encounter povidone molecules more frequently during its sublimation.

I just got a 4 liter quickfit erlenmeyer and its sufficent to extract 1g at the time :D

The duration of each extraction is 15minutes.
So i guess is totally worth it.

[Edited on 18-4-2004 by _navarone_]




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[*] posted on 18-4-2004 at 00:27


For me i think povidone iodine is going to be cheaper than the process from KI. Sure i can find iodized salt , but they have only little amounts of KI. Though the process of getting I2 from KI is easier; just bubble Cl2 through the solution.



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[*] posted on 18-4-2004 at 08:40
You think so...


Well yeah. to separate iodine from potassium u got to bubble Cl2 trough it.
But then you got to sublimize the iodine solution anyway to get all of it.
So in the KI extraction U need chlorine and heat.
In the povidone one u just need heat.
So thats why i suppose Povidone extraction is less messy.

Of course if you dont have the labware that i posted......you betta extract it from KI.

[Edited on 18-4-2004 by _navarone_]

[Edited on 18-4-2004 by _navarone_]




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[*] posted on 16-4-2008 at 15:29
Costs


I was excited to see that someone put some thought into a feasible extraction method, however if according to your yeilds from starting weights. We would be talking over a hundred dollars just to get close to an oz? Is that right?
Apologize ahead of time if I computed your weights incorrectly but in Vegas 8oz of Povi is running almost $13 for 8 oz to get a litter a min of 3bttls for 9grms. So again times say 3? Is that correct?:o
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[*] posted on 16-4-2008 at 15:30


What has the world come to that there is no cheaper way.....
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[*] posted on 16-4-2008 at 16:11


This is rediculous! 10mg of I2 per mL? That's 10g for every liter! Wow... It would be cheaper to buy KI at $200 a kg!

Why would anyone do this?!




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[*] posted on 16-4-2008 at 16:34


Now that I am going to sound like a total idiot. I am familiar with Pot. Io (KI). What is CI2 according to previous entries it seems to be a nec. element for proper extraction. Can you use io table salts, or is KI something I need to obtain from a Chem Dealer?
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[*] posted on 16-4-2008 at 23:36


Cl2 is diatomic chlorine gas. You can use it to extract I2 from KI but it's overkill. Not to mention the Cl2 contamination you will get.

H2SO4 and 25%-35% H2O2 is the best method in my opinion.

You will have to get KI from a "Chem Dealer". I have an extremely cheap source but I am very protective of it because I know that as soon as LE starts busting meth labs full of KI it will be gone (listed).

No offense but you only have 3 posts (all in the povidone I2 thread) and an obscure username so I don't feel good about divuldging the source to you. But if you are resourceful you will find it...




"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think, free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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[*] posted on 17-4-2008 at 03:35


And there's always ebay...
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[*] posted on 17-4-2008 at 05:16


True, if you don't mind paying out of your ass for miniscule amounts.



"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think, free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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[*] posted on 17-4-2008 at 08:59


It sometimes crops up for a reasonable price - certainly much cheaper and less hassle than Betadine etc.
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[*] posted on 17-4-2008 at 14:46


Unfortunately KI is not an option here, as its in the same class as I2. If the US restricts I2, KI must surely follow - those who can use I2 for illegal purposes, should have no problems with the high school oxidation of I-. Unfortunately the restriction on I in any form is just about the only effective 'precursor control' theyve come up with because theres no high concentration source of this element in everyday life. The restriction on P is much less severe, because its all around. But really I dont see the point in restricting either, once you remove the ephedrine, the illegal use is gone, and they become ordinary chemicals. I wish theyd make chemistry a mandatory subject at school so all these lawyers and politicians would know what they are talking about.
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[*] posted on 17-4-2008 at 19:24


Chemistry was mandatory at my school and still nobody had any clue. Even the ones that made all As in it. As long as you do all the homework and kiss ass that's all it takes.



"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think, free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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[*] posted on 17-4-2008 at 21:28


Pardon my rant but this will be the first and only time that I do this since this is not the forum to do it. But Eph will never become illegal since there is to much money to be made by pharmeceutical companies. And I totally understand the hatred that is shown by legitimate chemists at the tweekers who put this current situation into motion. However I think what the biggest problem is... you have a government who's main concern was to hurt its own people by locking them up for long periods of time and not being concerned with the huge mexican trade that took its place. Where they are producing far larger numbers than any american cook even dreamed of. Yet all they face is possible deportation only to return in a week. The feds are famous for misinformation and promoting fear. They did not affect the fact that meth is still the #1 drug within the US but changed the means of its accesibility. Taking money out of the american cycle and laying it down outside of our borders. Now that is intelligence. It reminds me of the commericals that ran a few years ago about how puchasing this illegal drug from american cooks was funding terrorist yet the only person I knew that was being funded was 7-11's,home depots, and wal-marts :). But can you say that know when most of this money is being diverted to a country which is so based in poverty that it doesnt care who it goes to bed with. I myself am amazed by science, I will never be as smart as some of your contributors that I can admit. But with this intellegence I see sometimes lacking of common sense. I mean that with no offense. I can never justify the actions of many of these people. But isnt the point of science- the desire to understand things, carrying it out through experimentation, and the such. This does happen in many ways legal or otherwise. Its always easier to say that what you do is perfectly ok its the other people that have the sickness. But I think thats just a little bit too judgemental.
Again sorry to be wasting your time, but I just had to get that off my chest being that at one time or another I have been on both sides of this fence.
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[*] posted on 17-4-2008 at 21:46


Who the hell was being judgemental? Because I wouldn't give out a source of a chemical whose regulation is imminent? I don't care what you or other people do in their own home. I just won't contribute to chemicals becoming more regulated no matter who's fault it truly is.

Also, I believe it was heroin that started the "drugs fund terrorism" bullshit because large quantities are made in Afghanistan (now, anyway).

This country IS to blame. But so are careless meth cooks.

I have a feeling this basically useless thread will be locked... maybe...




"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think, free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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[*] posted on 18-4-2008 at 04:45


Sorry to be a killjoy, but in terms of economic feasibility, I'd have to suggest (if KI is not an option and it ain't anymore, least hereabouts), then it might be worthwhile purchasing Kelp - you can buy it by the metric ton, it is not regulated, is available at mild markups from hippy stores and contains appreciable quantities of iodine.

Insofar as separating PVP & I2, I'd pretty much have to suggest that you read up on what happens to PVP when it's solution is mixed with phosphate salts (ie. it salts out pretty rapidly according to the lit) - which might be of some use - given that it would make the isolation & drying of the PVP-I2 rather simple. Once you have the problem nice and dry, it might be worthwhile looking into what organic solvents I2 is soluble in and which ones PVP ain't (and vice versa). Soon as you find one that one is freely soluble in and the other ain't, I suggest you race back here and tell us about it;), I'd suggest maybe pentane/hexane/etc.

The lit also says that PVP is liable to cross-link when exposed to protic acids, which renders it insoluble in water. If you oxidise I2 to iodate it will go yellow, addition of aluminium (like a suitable, ACS reagent grade, pull-tab off a drink can) will see the iodine given off as a gas, ready to condense on any suitable surface, like your eyes, skin, roof, or perhaps even a coldfinger. Or so I was once told by someone I met long ago (they found out by overoxidising KI with OCl till it went sulfur-yellow).:o




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[*] posted on 18-4-2008 at 09:23


I don't think getting iodine out of a np solution will be easy, unfortunately.
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[*] posted on 18-4-2008 at 11:00


LSD25, I thought the only place KI is hard to obtain is in the US and it's still available here. At least on the internet.



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[*] posted on 18-4-2008 at 18:41


Iodine: http://en.wikipedia.org/wiki/Iodine - BP 184.3C

Hexane: http://en.wikipedia.org/wiki/Hexane - BP 69C

Why are they going to be so difficult to separate?

I2 is also highly soluble in diethyl ether (according to Wikipedia, 20.6 g/100 ml at 17 °C, 25.20 g/100 ml at 25 °C), while PVP is insoluble (or less than 1%, or <1g/100mL) - if it is too difficult to strip off hexane, ether (BP 34.6C) should be a breeze (shit, the ether wouldn't even need to be dry prior to the initial extraction step).

As to the extraction of iodine from seawater/kelp, here are some ref's:

Quote:
10.13.2 Extract iodine from kelp
See diagram 13.15.3
Iodine is one of the microelements necessary for the human body. Sea water contains about 0.000005% of iodine that can be absorbed and concentrated by some marine living beings. There are 1000-4000 mg of iodine existing as iodides in kelp of per thousand grams. Burning kelp gathers the iodides in ashes. Decoct the ashes in water, acidify the resultant iodide solution and then evaporate it to dryness. The follow-up oxidation with potassium dichromate produces iodine, which is then separated by sublimation.
K2Cr2O7 + 6KI + 7H2SO4 ---> 4K2SO4 + Cr2(SO4)3 + 3I2 + 7H2O
Weigh and cut 40 g of commercial dried kelp into small pieces and put them in an iron vessel. Burn the kelp chips with an electric heater in a fume cupboard until all the chips are completely turned into ash.
Transfer the ashes to a beaker, add 40 mL of deionized water, heat and boil the suspension, and add more water to make the filtrate 30 mL after filtering. Add drop by drop dilute sulfuric acid (2 mol / L) to the filtrate until its value of pH becomes neutral. Put the neutralized filtrate in an evaporating dish, evaporate it by heating to dryness. The residues are parched and ground and uniformly mixed with 2 g of potassium dichromate. Transfer the mixture to a dry tall beaker. Stand a flask containing cold water on the mouth of the beaker. On heating the beaker to sublimate the produced iodine, iodine vapour condenses on the cooler sides of the flask. Stop heating when there is no violet red iodine vapour appearing any more. Collect the obtained iodine crystals.

From here: http://www.uq.edu.au/_School_Science_Lessons/topic10.html#10...

The apparatus is here: http://www.uq.edu.au/_School_Science_Lessons/13.07.03chd.GIF


I'd sorta suggest you use hypochlorite and hydrochloric acid, rather than the suggested sulfuric and dichromate route - but it is up to you.

Some additional interesting articles:

http://www.rsc.org/ej/AN/1999/a902373i.pdf

http://old.iupac.org/publications/pac/1998/pdf/7008x1567.pdf

http://aaa.nevada.edu/pdffiles/Task%2015%20Year%202%20Renewa...

http://www.atsdr.cdc.gov/toxprofiles/tp158-c7.pdf

http://andrew.ucsd.edu/co2qc/handbook/sop02.pdf

And lastly, A Dictionary of Chemistry, By Andrew Ure, William Nicholson: http://tinyurl.com/3nnyug

The average yield is stated to be between 1-4g/kg kelp, so this ain't going to be a small scale setup.

[Edited on 18-4-2008 by LSD25]




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[*] posted on 18-4-2008 at 21:22


DAMN! You would almost be better off extracting KI from "radiation pills" or solution. Unfortunately they tend to be expensive and I'm sure kelp is cheap. IF you can find a source of 50 kilograms or so (unless you live by the ocean!). I'm not sure how much work would be involved in harvesting that much kelp but it sounds like a lot.

[Edited on 4-18-2008 by MagicJigPipe]




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[*] posted on 19-4-2008 at 01:08


Quote:
Originally posted by LSD25
Iodine: http://en.wikipedia.org/wiki/Iodine - BP 184.3C

Hexane: http://en.wikipedia.org/wiki/Hexane - BP 69C

Why are they going to be so difficult to separate?

I2 is also highly soluble in diethyl ether (according to Wikipedia, 20.6 g/100 ml at 17 °C, 25.20 g/100 ml at 25 °C), while PVP is insoluble (or less than 1%, or <1g/100mL) - if it is too difficult to strip off hexane, ether (BP 34.6C) should be a breeze (shit, the ether wouldn't even need to be dry prior to the initial extraction step).

Iodine and povidone form a complex (kind of like iodine and starch) so you can not just extract iodine, you need to break the complex first. By extraction you would just extract a small amount of free iodine (depending on the complex stability constant and iodine partition constant for the used water/solvent system). You would need too many extractions to extract a useful amount.
However, you can just sublime the iodine out of the iodine-povidone complex since the complex surely decomposes on heating.
Yet, I don't see why would someone want to do that except out of curiosity or if he just needed a tiny amount of iodine. That certainly is not a particularly economic way of getting iodine. Compared to this, even the proposal of getting it out algae sounds reasonable if they truly contain 0.1-0.4% "iodine" by dry weight. Burning them up should give a relatively small amount of ashes and thus highly enriched with iodides.
But since iodides are still available at (my) local chemical supliers and since I curently need no iodine...




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LSD25
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[*] posted on 19-4-2008 at 02:03


Yeah, my thoughts exactly on the extraction of kelp/other seaweeds (apparently this was an actual industrial process, well, back when it was okay to boil down cows hooves and shit) - this crap washes up on beaches and can be collected for fuck all. Take along a drum or take it home, burn it - I'd expect the total solids from the burning of kelp to be no more than about 1-5% of the total, which means that the KI content of the ashes is seriously high. Might be worthwhile looking into the extraction of the KI as is, you'll save a whole lot of time by not needing to go through KI --> I2 --> HI --> KI.

Wouldn't the PVP-I2 complex bear some resemblance to something between NMP.(HBr)3 / NBS / Quat. Halides?




Whhhoooppps, that sure didn't work
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