Junk_Enginerd
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Fastest way to make Iron (III) chloride without peroxide?
I want to make some magnetite, for ferrofluid and for transformer cores. As some may know, this requires iron (II)- and iron (III) chloride in a
specific ratio for best results.
The iron (II) chloride is easy enough to make. The iron (III) chloride is less so... Hydrogen peroxide is really difficult to acquire for me, so that
one is out. I know (II) chloride will eventually oxidise to (III) chloride with air exposure, but leaving a container like that open to air tends to
murder anything steel nearby, plus I'm not sure how I would tell when it has oxidised completely. If I can't be sure it's fully oxidised, it'll be
impossible to get a good ratio of the chlorides for good quality magnetite formation.
What other options are there? I've got good equipment for electrochemical processes. Is that a good route?
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unionised
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Nitric acid would be traditional if you were doing analytical chemistry, but watch out for the NOx fumes.
Electrochemical oxidation should work fine.
In principle, there should be a distinct drop in current when the Fe(II) is used up.
Bleach and HCl would also work.
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Junk_Enginerd
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Great, thanks! It'd also be great if you could flesh that out a little. I've got slightly too little knowledge to connect the dots myself.
How would the nitric acid approach work? Wouldn't I just set myself up for nitrates instead?
How would I best electrochemically oxidize it? If I have an iron anode and an iron cathode, I assume I would just be moving metal from anode to
cathode and not doing much to the solution... With a platinum anode, that should take care of the oxidizing, right? But how do I stop the iron ions
from just plating out on the cathode?
And bleach seems obvious now that you mention it. But I'd rather avoid adding a bunch of sodium or calcium to the mix since I'm not too confident in
my ability to remove them...
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clearly_not_atara
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If you just start with iron (III) oxide and dissolve it in HCl, the product should be FeCl3. So you should be able to precipitate Fe2O3 from your
hypochlorite solution (if it doesn't spontaneously deposit) and then dissolve that in some clean HCl. Maybe wash it to remove sodium.
[Edited on 04-20-1969 by clearly_not_atara]
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DraconicAcid
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Iron(II) oxidizes easily to iron(III) in basic conditions, because iron(III) hydroxide is far less soluble than iron(II) hydroxide. Add enough
ammonia to an iron(II) chloride solution to precipitate they hydroxide, let it sit exposed to air, then redissolve in hydrochloric acid. If you want
to minimize the amount of ammonium ions present, boil off excess ammonia before acidifying.
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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hodges
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You could always use an aquarium bubbler to bubble air through the FeCl2 to convert to FeCl3. Might not be as fast as using H2O2, but I'm guessing
will not take real long.
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Texium
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Thread Moved
14-9-2023 at 11:54 |
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