exaeta
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Aluminum Purification
I've been trying to produce aluminum salts, but they end up with a yellow color. Looking for some suggestions for purification.
I have tried producing aluminum sulfate from aluminum foil and copper sulfate, and this produces a solution which when boiled, turns sticky before
solidifying due to the removal of water. This solution ends up with a yellow color. Aluminum foil plus hcl also dries to a yellow looking salt.
I tried using potassium hydroxide to remove any iron, but no luck... everything, including the aluminum, stayed in solution. I'm guessing this is a
potassium aluminate? It has a blue-green color, not what I was expecting. I thought it might be iron(ii), so I added hydrogen peroxide, and it turns
it orange for a moment, but it didn't seem to precipitate anything. There may have been a small amount of iron filtered of, as there is a slight green
stain on the filter paper, but I don't know how to get the aluminum back out after this point, since I wasn't expecting it to complex.
Anyone have any tips for dealing with impurities in aluminum foil, what they might be?
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macckone
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Composition depends on alloy.
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Sulaiman
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I thought that the aluminium used to make foil is an alloy,
but after reading the above I did a little research ...
it seems that modern aluminium cooking foil is almost pure aluminium,
but with a lubricant applied to the surface to aid in the rolling process !
Other sources state that there may be chromium, copper, iron, magnesium, manganese, silicon, titanium and zinc in sub-1% quantities.
So, maybe cleaning the surface with a suitable solvent
(I don't know which solvent, I'd try isopropyl achohol,acetone or detergent and water, maybe a rinse with dilute hydrogen peroxide)
before use would eliminate the yellow impurity ?
[Edited on 14-10-2019 by Sulaiman]
CAUTION : Hobby Chemist, not Professional or even Amateur
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draculic acid69
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When I looked into this a few years ago I kept seeing iron and silicon as part of the composition of Al foil.
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morganbw
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I think that Aluminum foil is intended to be pure.
The other things in it are impurities.
There are many Al alloys but the Al foil is not meant to be one.
If you are trying to make some Al salts you will be dealing with a small part of Al oxides as well.
[Edited on 10/15/2019 by morganbw]
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rockyit98
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use aluminium wires that use in electrical wiring ,its 99.9 pure .because alloying aluminium with other elements tend to lower it's conductivity
(higher resistance) electrical cables are very pure.
in the making of such high purity by
2Al{alloy} + AlCl3{gas} → 3AlCl{gas}
3AlCl{gas}-------->2Al{pure} + AlCl3{gas}
https://en.wikipedia.org/wiki/Aluminium_monochloride
"A mind is a terrible thing to lose"-Meisner
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draculic acid69
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Copper wire and h2so4 equals coppersulfate + an impurity from either the metal or the acid in my experience and when stripping wires a few hrs ago the
silvery non copper cable wires were hit with a blowtorch for a few seconds and then scratched and they turned a coppery color.but unless heated with
the flame no amount of scratching would reveal the copper color.they were obviously an alloy of something.point is just bcoz it's supposed to be pure
metal doesn't mean it is.cost cutting in shitty Chinese products and all.
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