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cyanureeves
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i will try sometime this weekend, i just dont understand this whole thing sometimes.
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cyanureeves
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<img src="http://i1190.photobucket.com/albums/z444/scarface130/DSCI1329_zpsa322e380.jpg" width="800" />you are very much in the right
m1tanker78.not all the red was copper but in fact nickel as well even though it was no different in color than the copper. a strong magnet did pick up
the nickel powder which was blue and not green.my next step involved using aluminum to drop both the metals but stopping when the solution looked more
green than blue.hoping that copper would precipitate first i removed the aluminum along with the red sponge as it started to just pick up nickel.the
nitrated solution did not precipitate anything with acetylene but in fact just precipitated hydroxides when ammonium hydroxide was introduced.why the
hydrochloric acid solution in which i dissolved the nickels with 5 volts did not even fume when i added ammonium hydroxide is a mystery to me.why the
hydrochloric solution did not fume or drop hydroxides is also something i did not expect.the whole thing just started to make the blue amine complex
then suddenly turned rust red.the acetylene does drop quite a bit of copper enough to let me nickel plate.
<!-- bfesser_edit_tag -->[<a href="u2u.php?action=send&username=bfesser">bfesser</a>: reduced
image size(s)]
[Edited on 26.1.14 by bfesser]
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TheChemiKid
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I am sorry if this has been said before, but the thread is so long it is hard to find anything. I tried method one, but the nickel just would get
attracted to my magnet (It was a 1/2" x 1/2" x 1/2" Neodymium magnet). now I have an annoying powder of metals on my hands. What should I do?
When the police come
\( * O * )/ ̿̿ ̿̿ ̿'̿'̵͇̿̿з=༼ ▀̿̿Ĺ̯̿̿▀̿ ̿ ༽
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cyanureeves
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try anything chemkid but be careful with acetylene because it appears it also bonds with nickel,so does vinegar,sulfuric acid, etc. and it also drops
with aluminum along with copper.you can plate out most of copper with an annode but some will remain in solution.once they are converted to their
carbonates or hydroxides then they are almost impossible to separate.i think it has been suggested that molten sodium hydroxide might separate copper
only like plante1999 did with chromium.good luck but dont give up entirely.
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bismuthate
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Ok so after a while I have come up with a few ways to separate the nickel and copper.
First the nickel should be dissolved in HNO3.
1Then you can add a solution of potassium ferrocyanide. After that just filter the red/brown copper ferrocyanide and you are left with a copper free
solution that you can get nickel from.
2 Add KI or NaI to the solution and again filter to get your nice pretty nickel solution. (On a side note oddly enough the iodine that should nave
apeared does not but remains in solution until and acid is added (this may be because I used realy impure NaI that I made from povidone iodine))
3 Add sodium chromite (which is actually rather easy to make)
4 I have heard about copper borate being made via copper sulfate and sodium tetraborate and have experimented on it but have not tested the method
definitively. I can if anybody has an interest in it.
5 I found that simpley using an excess of nickel and letting it sit for a few days in nitric acid give a rather pure nickel nitrate solution.
If anybody has any interest in these tell me and I can do more research and post a procedure.
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cyanureeves
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you mean add nickel to copper/nickel nitrated solution???
[Edited on 4-21-2014 by cyanureeves]
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bismuthate
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Well I meant that I used a bunch of nickels and added them to not enough nitric acid to react with a 5th the coins.
Althogh be warned if you did this you would need to purify it after.
[Edited on 21-4-2014 by bismuthate]
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m1tanker78
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I think a clever design for electrolysis without having to weld the coins or pieces together is in order. Without yet reading the last few
pages, I got remarkably pure metal powders via electrolysis and a displacement reaction. Problem is I cheated and welded the coins together to form
the anode. I'll bet a small car battery and a couple of graphite rods will make a fine 'welder' in a pinch.... never mind.
I'm thinking along the lines of a titanium wire cage tumbler filled with alloy coins/pieces. Apply gentle current (see upthread for specs) and clean
copper sponge from cathode periodically. After some time, you'll hold quite a bit of copper powder and if desired, you can drop out relatively pure
nickel powder with pure aluminum (again, see upthread).
I do like that people are thinking of and at times trying other ways to make this alloy divorce..
Tank
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jiexiang88
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Forgive me if this was already posted, but I do not have time to go through all 10 pages of this thread
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CrossxD
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is nickel borate soluble in water?
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Fulmen
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I might be onto a workable solution to this. I started by dissolving some cupronickel coins in a HCl/NaNO3-mixture. I then tried precipitation with
NH3, and while a green precipitate formed I was unable to separate this out in any way. Gravity filtering just clogged the paper while it passed right
through when vacuum filtering. No surprise there. So I figured I'd give the acetate route a try, copper acetate should be less soluble than nickel,
giving me at least partial separation.
So I acidified the solution (now containing copper, nickel, chlorides, nitrates and ammonia), but got no crystallisation even with cooling.I figured
it needed to be more concentrated, so I started to boil it down. After reducing it to appr. 1/2 the volume I suddenly got a pale green precipitate
again, accompanied by a strong acetic acid smell. And this time the precipitate was much coarser and easily filtered.
I guess the acetate simply boiled off, increasing the pH to the point where the nickel hydroxide would form again. But the slow hot process seems to
promote crystal growth much better than the direct precipitation did.
We're not banging rocks together here. We know how to put a man back together.
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DraconicAcid
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Quote: Originally posted by Fulmen | I then tried precipitation with NH3, and while a green precipitate formed I was unable to separate this out in any way. Gravity filtering just clogged
the paper while it passed right through when vacuum filtering. No surprise there. |
Nickel hydroxide is awful to try to filter, in my experience. But if you had a high concentration of nickel, you should have gotten Ni(NH3)6Cl2,
which is much less soluble than the copper complex Cu(NH3)4Cl2. That might be a way to separate them.
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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Fulmen
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Metal hydroxides can be a real pain, I've tried copper oxide this way before and it's a complete mess.
My "discovery" seems related to the ammonia/ammonium carbonate leach for copper. In this process an ammonia/ammoniacal carbonate complex is generated,
in the subsequent boil the ammonia is driven off and malachite (Cu2CO3(OH)2) precipitates. And this precipitate is a dense, fine powder rather than
the amorphous gel obtained by direct precipitation.
I'm not completely sure if the precipitate is nickel hydroxide yet, but it's the most likely culprit. I guess I could do a silver nitrate test for
chlorides, any other suggestions?
Update: The separation of copper and nickel seem to be quite good. I can add a fair amount of ammonia to the supernatant liquid (dark green) without
any more precipitation, an excess produces a blue solution indicating a copper amino complex.
[Edited on 3-11-16 by Fulmen]
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m1tanker78
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Fulmen, your precipitate could be copper hydroxychloride rather than nickel hydroxide. There is theoretical as well as experimental evidence for this
a few pages back in this thread.
Chemical CURIOSITY KILLED THE CATalyst.
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Fulmen
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You could be right. I dissolved the precipitate in sulfuric acid, and the result was a blue-green color that doesn't match either copper or nickel. So
it doesn't look good for separation this way.
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CrossxD
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Today I tried to separete them by reduction by reducing sugars.
I made solution of glucose-fructose, than dissolved in that solution sodium carbonate and than citric acid and let it on about pH 9,than I mixed it
with my Cu/Ni solution and heated up.
Brick like red solid precipitated
I hope it will be good for u 2
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Fulmen
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But did you get a precipitate that could be filtered? I tired adding some acid-hydrolyzed sugar, and I did get a brown precipitate but nothing that
allowed for separation.
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symboom
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Extraction the cheapest way
It seems turning to organic chemistry for the solution is the simplest way
Materials:
Nickels
Acetic acid
Hydrogen peroxide
Asprin
Sodium bicarbonate
starting with nickels desolve in vinegar and hydrogen peroxide mixture
Nickel acetate and copper acetate is formed
Prepare sodium aspirnate
From sodium bicarbonate and aspirin excess asprin to prevent nickel from percipitating
Mixing solutions copper is percipitated while sodium acetate is formed
Possibilities
In sol.
Sodium acetate
Acetic acid
Aspirin
Hydrogen peroxide
Nickel acetate/asprinate
Copper aspirinate is insouble filter off
Nickel aspernate is soluble stays in solution
Precipitate nickel carbonate by adding more sodium bicarbonate
[Edited on 6-11-2016 by symboom]
[Edited on 6-11-2016 by symboom]
[Edited on 6-11-2016 by symboom]
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zwt
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Ingenious!
Almost as much as when it was suggested 3 years ago, in this thread.
...and 5 years before that, in another thread.
One wonders why a repeatable procedure, based on this principle and with things like actual measurements, hasn't been posted yet.
Could it be that this doesn't work nearly as well in practice as it does in theory? When I experimented with this some months ago, that's what my
results implied.
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Fulmen
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Getting an insoluble precipitate isn't enough, it also needs to be coarse enough to allow filtration.
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Fulmen
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The ammonia seems to be a fairly selective, it readily complexes the copper without dissolving the nickel. Even with enough ammonia to dissolve filter
paper the green precipitate was unaffected while the supernatant liquid stayed blue. Filtration is a major pain, although boiling the suspension seems
to cause some slight flocculation. It will probably need several days of standing/decanting, but it's worth a shot.
We're not banging rocks together here. We know how to put a man back together.
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Fulmen
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The decanting/washing of the nickel hydroxide is slow work as expected, but at least the strong color of the copper complex gives a good indication of
the progress.
Recovering the copper turns out to be the easiest part. Start by adding enough sodium hydroxide to cause a slight precipitate (not important, just
speeds up the process), then boil the solution. As ammonia is driven off copper hydroxide precipitates out, but in a much coarser product than you
will get with the direct precipitation. It could be possible to do this with the nickel as well, but it seems to require an awful lot of ammonia to
dissolve it.
We're not banging rocks together here. We know how to put a man back together.
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m1tanker78
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Fulmen, what do you mean by 'the ammonia'? Provide some detail of your procedure.
Chemical CURIOSITY KILLED THE CATalyst.
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Fulmen
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I'm just throwing science at the wall to see what sticks :-)
I started by dissolving coppernickel in 30% HCl with NaNO3 added as an oxidant, then precipitated it as an hydroxide with sodium hydroxide. Adding
ammonia (appr 10%) dissolves the copper as the amino complex, even with a decent excess of ammonia no nickel hydroxide seems to dissolve. The solid
nickel hydroxide can then be filtered off (or separated by decanting) and dissolved in the acid of your choice.
The remaining copper can easily be recovered by boiling, this drives off the ammonia reverting the copper to it's hydroxide again. This is an
effective method as it produces a much heavier precipitate than a direct reaction with say sodium hydroxide, allowing for gravity filtering without
instantly clogging the filter.
Sadly I did not get a complete separation this time, after reacting the nickel hydroxide with sulfuric acid I ended up with some copper sulfate as
well. This could easily be seen by the color of the crystals and was confirmed by inserting a steel wire into the liquid. Copper quickly plated out.
Luckily copper sulfate is slightly less soluble in cold water, so by washing it with cold water I was able to get better separation. Now a steel wire
forms a black precipitate, which I assume is nickel.
My mistake was probably that I didn't wash the precipitate with enough ammonia, I was running a bit low and the fine suspension made it time consuming
to do repeated washes. Perhaps stronger ammonia would be more effective, but 10% was all I had.
Suggestions for further investigation: Dissolving both the nickel and copper hydroxide in stronger ammonia. This way one should be able to get a
denser, more filter friendly nickel hydroxide, and the apparent difference in solubility should provide separation.
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m1tanker78
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As I recall, Sedit's procedure (with ammonia) didn't include an intermediate precipitation of the metal salts. He was just adding ammonia directly to
the solution of metals. What you're saying is that adding ammonia to the mixed metal hydroxides selectively complexes the copper, allowing the nickel
hydroxide to be filtered or decanted.
Are you washing the hydroxides prior to adding ammonia? It seems very reasonable to assume that a slight excess of NaOH should be added to the
solution of metals.
How are you testing your products?
Chemical CURIOSITY KILLED THE CATalyst.
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