Sciencemadness Discussion Board

preciptate iodine from solution

Joauml - 31-8-2009 at 13:09

Recently I bought a iodine solution (probably iodine in ethanol) and found only one method to preciptate the iodine: by reacting it with NaOH and then react the products with HCl + H2O2(or even just with HCl), but, if possible, I want some way to preciptate the I2 without the use off chemicals like NaOH or HCl + H2O2. If someone knows a better method for preciptate the iodine, please post her :D


[Edited on 31-8-2009 by Joauml]

kclo4 - 31-8-2009 at 13:18

It is likely a solution of Iodine and potassium iodide. KI greatly increases the solubility of I2.

When it is all said and done, the best way is going to be to use chemicals to precipitate the iodine, but you *might* be able to evaporate some of the solution, but the KI that I think is present is really going to make it difficult to get a decent yield. Plus if you do use chemicals you can get the KI's iodine as well, so you'll end up with more iodine.

Joauml - 31-8-2009 at 13:35

I'm not so sure tha it have KI as I can't preciptate it with HCl + H2O2, what in theory would oxidize the iodide to iodine and cause to the iodine to precipitate and, I'm ok to use chemicals to preciptate it, I just don't want to use NaOH or H2O2 as I don't want to waste them

Before anyone ask, I don't want to make NI3... lol


I bubled chlorine trough the solution and something yellow preciptated, ICl3? Wasn't it just stable in a chlorine atmosfere?


sorry for my bad english =\

[Edited on 31-8-2009 by Joauml]

watson.fawkes - 31-8-2009 at 17:33

Quote: Originally posted by Joauml  
I'm ok to use chemicals to preciptate it, I just don't want to use NaOH or H2O2 as I don't want to waste them
I would recommend focusing on the cost of getting your precipitate. NaOH and H2O2 are two of the cheapest reagents around, at least in the US. Please, if you would, do a trial computation of getting your iodine with these two reagents, if only to have a baseline for comparison.