hydride_shift
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FeOCl and drying Fe(III)Cl3
My intention is to synthesise anhydrous Iron (III) Chloride from iron.
20g steel wool was disolved in 150mL 32% swimming pool hydrochloric acid with about 100ml of water.
Traces of hydrogen sulfide could be smelt as the metal dispeared into a foaming green solution.
Fe + 2HCl -> Fe(ii)Cl2 + H2
The solution was filtered removing solid carbon and unreacted metal.
200ml of 3% hydrogen peroxide was dumped into the solution which instantly turned the solution from a bright green to dark brown.
2Fe(ii)Cl2 + H2O2 +2HCl -> 2FeCl3(aq) +2H2O
Now this is when i made the mistake off trying to boil off the liquid.
Purplish brown crystals appeared as an acrid HCl stench became apparent.
2FeCl3 + 2H2O -> FeOCl + 2HCl
Identity of the chocolate coloured powder is confirmed to be FeOCl by decomposition. A yellow solid evolved on the sides of the test tube as the solid
in the test tube became back.
6FeOCl -Δ-> 2Fe(iii)Cl3 + Fe2O3
Anyone had experience preparing the anhydrous Fe(III)Cl3?
I was considering simply saturating the solution with NaCl and hoping for it to crash out, but other sources say thionyl chloride is necessary:
Pray, Alfred R.; Richard F. Heitmiller, Stanley Strycker (1990). "Anhydrous Metal Chlorides". Inorganic Syntheses 28: 321–323
Also anyone know any uses for FeOCl?
Tempted to scale up a dry distillation but it seems fairly wasteful and messy.
Any input would be appreciated
inb4
https://www.sciencemadness.org/whisper/viewthread.php?tid=40...
https://www.sciencemadness.org/whisper/viewthread.php?tid=27...
[Edited on 16-3-2014 by hydride_shift]
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HgDinis25
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I've prepared Ferric Chloride several times and I've always boiled the solution. I seriously dought that you can make the oxychloride by simply
hydrolisis of ferric chloride.
Nurdrage has a video covering the production of your desired product:
https://www.youtube.com/watch?v=43Xsh9J7S-g
Wiki states the following: FeOCl is prepared by heating iron(III) oxide with ferric chloride at 370 °C over the course of several days. http://en.wikipedia.org/wiki/Iron_oxychloride
This procedures is much more difficult than a simple hydrolisis...
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BromicAcid
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Question is, are you trying to just isolate ferric chloride or more specifically anhydrous ferric chloride? It sounds like you want the latter, but
you will not be able to get quality anhydrous ferric chloride from aqueous solution. You can get the hexahydrate but on dehydration you begin to lose
your hydrogen chloride and leave yourself with a series of basic chlorides and finally oxychloride and oxides. It is too strong a Lewis acid to
isolate in this manner (same as aluminum chloride and more arguably cupric chloride and zinc chloride).
You are right to be concerned, check out "A course on Inorganic Preparations" in the library, it is an excellent text on simple inorganic salts to
practice on. Things like ferrous chloride are covered in great detail though the text only goes into detail on isolating ferric nitrate when dealing
with salts of the +3 type. Still, even for that the text recommends never heating to boiling and being very careful with the drying (prolonged drying
can lead to decomp of that material as well).
If you are still interested in the anhydrous material, Brauer's text in the library has a prep for the anhydrous material but it's as simple as
reacting chlorine with iron directly.
Personally I have always wondered to what degree the hydrolysis occurs. If it might be possible with careful drying to isolate some small portion of
anhydrous material, would be simple enough to check as the anhydrous ferric chloride should be soluble but I really do think that if you beat on it
and dry it to make it anhydrous you'll probably just destroy your product.
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DraconicAcid
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You may not get a stoichiometric FeOCl that way, but you will not get anhydrous FeCl3, either. A non-stoichiometric mix of oxy/hydroxy
chlorides, most likely.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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blogfast25
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Indeed. But I've obtained FeCl3.6H2O by slowly boiling in a solution of FeCl3 in strong HCl. As long as there's enough acid present hydrolysis doesn't
occur. A bright yellow crystalline material is obtained. It's hard to get it to crystallise because it's so damn soluble.
Anh. FeCl3 is Fe filings/powder + chlorine gas but I wouldn't as Bromic does, call that 'simple'.
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BromicAcid
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Deceptively simple 
Simple in <b>theory</b>, does that sound better?
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blogfast25
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BA:
Somfink like that...
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