seilgu
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Recovering an old bottle of FeCl2
There's a 500g bottle of FeCl2 that turned brown and yellow.
I'm looking for ways to turn it back to green FeCl2 crystals/solution without significant costs.
https://chemistry.stackexchange.com/questions/75762/why-woul...
According to this it's probably hydrated rust which is not solvable in water. I could add some HCl but I don't want to waste a lot of HCl on this
cheap material. (If the chlorine is already in there why should I add more?)
If I just pour it all out and add water, can I expect the HCl remaining in the bottle to dissolve the iron oxides, then upon heating to drive out the
water to give back FeCl2 ?
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vano
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I do not know how much you need this compound. But I was not wasting hydrochloric acid. It is also a question of how clean the product will be. With
acid you can make a chloride solution at any time. If you can take a photo to understand what the situation is.
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Bedlasky
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Small amount of HCl and iron nails do the trick. Iron will reduce any Fe(III) to Fe(II).
[Edited on 15-2-2021 by Bedlasky]
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ChemTalk
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Quote: Originally posted by Bedlasky | Small amount of HCl and iron nails do the trick. Iron will reduce any Fe(III) to Fe(II).
[Edited on 15-2-2021 by Bedlasky] |
Came here to say the same thing. Steel wool will work too.
I purchased some FeSO4 once, and it turned light brown before it even arrived at my door.
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unionised
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I can't see why a simple recrystallisation wouldn't work.
The solubility curve isn't very good but it's easy to get round that.
Filtering the hot solution will strip out most of the Fe(III).
Adding a little HCl will probably help clean things up.
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seilgu
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Quote: Originally posted by Bedlasky | Small amount of HCl and iron nails do the trick. Iron will reduce any Fe(III) to Fe(II).
[Edited on 15-2-2021 by Bedlasky] |
I added a lot of HCl and a long nail but it seems to take forever. Also, do I have to use a lot of HCl for converting 500g of it?
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Boffis
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I use ferrous chloride as a reducing agent for aromatic nitro compounds but I have given up trying to prepare and store it in advance. I now prepare
it as require by the method Bedlasky described. I have used up all of my old ferrous chloride and now use ferric chloride hexahydrate + HCl + soft
iron nails.
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ChemTalk
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You should need very little HCl. Also the nail must be iron, and the outside of the nail should be iron, not rust / iron oxide. Personally I would try
steel wool as it would have more surface area.
I find it very hard to keep Iron (II) around, I think the air in my area has a lot of oxygen in it, lol.
Quote: Originally posted by seilgu | Quote: Originally posted by Bedlasky | Small amount of HCl and iron nails do the trick. Iron will reduce any Fe(III) to Fe(II).
[Edited on 15-2-2021 by Bedlasky] |
I added a lot of HCl and a long nail but it seems to take forever. Also, do I have to use a lot of HCl for converting 500g of it?
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