jamit
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iodine clock reaction - recovering the iodide/iodate
Just recently i performed the iodine clock reaction. My problem is that, I want to recover the 50g or so amount of potassium iodide which I used for
the clock reaction. I certainly don't want to throw it down the drain as the solution does contain valuable iodine/iodide.
My question is, how can I recover the iodide/iodine since it is mixed with acetic acid, sodium thiosulfate, sodium metabisulfite and potassium iodide
and iodine? Any suggestions?
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bismuthate
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The easiest way that I can think of is to mix it with enough HCl and H2O2 to convert all of the iodine into its elemental form. Then mix it with
enough MgSO4 to absorb all of the water and finally sublimate the iodine.
I can't give you any amounts without more info on how much of each reagent was used though.
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j_sum1
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I have not tried it yet but chemplayer on yt gives a nice isolation of iodine using persulfate. Worth a look.
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PartVIII
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You should probably oxidize it back to iodine using H2O2 and HCl, then lightly boil off as much of the solution as possible. Boiling point of iodine
is ~183C, so you should be good as long as you don't heat it too much.
Then, once the solution is concentrated, extract it with a nonpolar solvent like hexane. Boil off the hexane, and sublimate for purification.
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Volanschemia
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From experience, Iodine will start sublimating well before 183C, just as water evaporates below 100C, but usually more markedly with Iodine.
"The chemists are a strange class of mortals, impelled by an almost insane impulse to seek their pleasures amid smoke and
vapor, soot and flame, poisons and poverty; yet among all these evils I seem to live so sweetly that may I die if I were to change places with the
Persian king" - Johann Joachim Becher, 1635 to 1682.
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j_sum1
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Whatever you do, you want a sublimation step to remove the starch.
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jamit
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Quote: Originally posted by bismuthate  | The easiest way that I can think of is to mix it with enough HCl and H2O2 to convert all of the iodine into its elemental form. Then mix it with
enough MgSO4 to absorb all of the water and finally sublimate the iodine.
I can't give you any amounts without more info on how much of each reagent was used though. |
I'll definitely give the HCl and h2o2 a try to convert everything to iodine... I expect the iodine to drop to the bottom then, i can decant and try to
purify it.
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PHILOU Zrealone
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Transform into I2 and extract it with a halogenated solvent...
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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