Dalis
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Magnets
I have collected a few magnets for my element collection. I would like to know who I could figure out what kind of magnet it is. I have a crushed
magnet from a BaneBots motor, 6 hardrive magnets, and a few from headphone speakers. If anyone got any good ideas as to acquisition of other metals,
do let me know.
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diddi
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your magnets will be mixtures of elements and prolly not much use as specimens. the hard drive magnets contain Nd, Fe and B. good luck separating
them. (there are several threads on SM) The other magnets may contain Fe, Ni, Co, Sm depending on the construction method and application (eg high
end speakers often use CoSm). Again, hard to extract the individual elements.
Many metals can be obtained in everyday items, and it really depends on how fussy you are about presentation and purity. eg if you want some lithium,
buy a lithium battery and rip it open. (see SM threads) but beware that it will blacken almost instantly.
if you want tungsten, grab an incandescent light bulb filament...
the bulk of elements you will find are combined and required at least some chemistry to extract, but that is the fun of it all.
Beginning construction of periodic table display
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MrHomeScientist
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I don't know what a BaneBot is, but headphone and hard drive magnets are almost certainly neodymium - it's the only type that meets the requirement of
small size and high strength. As diddi said, this is an alloy: Nd<sub>2</sub>Fe<sub>14</sub>B. As you can see, the majority is
iron. If you want to separate out the components of the alloy, it's a hell of a task (trust me). Getting the boron out is easy (dissolve the magnet in
sulfuric acid and it will be left over as a black powder), but separating out the iron and reducing the Nd back to a metal is the tricky part.
See the thread The trouble with neodymium... for all our efforts towards this goal. Right now I have some clean NdF<sub>3</sub> that I plan on
reacting with lithium metal to free the elemental neodymium, using an inert atmosphere crucible I built. I haven't tested it yet, though, so who
knows. Exciting times ahead though!
A possible way to test what you have is to dissolve a piece of each magnet in sulfuric acid. Neodymium magnets will yield a dark purplish solution.
Several of my magnets I tried yielded a green solution, which I suspect (but am not sure) might be the samarium variety.
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Dalis
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So to remove nickel plating I would have to either crush the magnets or use nitric acid right? Also BaneBots is a motor manufactor.
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blogfast25
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Quote: Originally posted by Dalis  | | So to remove nickel plating I would have to either crush the magnets or use nitric acid right? Also BaneBots is a motor manufactor.
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I demagnetise the magnets first on a hotplate, then crush them somewhat. I don't remove the nickel (it's quite resistant to HCl/H2SO4). Any Ni that
does dissolve will stay with the Fe in later stages of the work-up.
I use 33 % HCl, in excess. H2SO4 didn't work very well for me: Nd sulphate is poorly soluble, even more so when hot. HNO3 is overkill as both Fe and
Nd are electropositive metals.
If you're looking to isolate the Nd, please report your findings in the thread linked to above (RE data are already too scattered over this forum).
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MrHomeScientist
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The way I did it was to heat the magnet with a propane torch for a couple minutes until it demagnetized (see: Curie temperature), snapped it into
several large pieces, and peeled off the Ni as much as possible. Demagnetizing makes it much simpler to work with. Don't worry if you can't get all
the plating off, since it shouldn't dissolve in sulfuric acid anyway*. The more you get off, the more magnet surface is available to react and the
faster it will dissolve. Warning: dissolving an entire hard drive magnet takes several days in my experience. Heating the solution should of course
speed this up a bit.
*Interestingly, though, I have had instances where the nickel mysteriously vanishes by the time the magnet is fully dissolved 
Edit: Dang! Blogfast beat me to it  But yes, see the thread I linked for more
info than you ever wanted to know about this process.
If I ever do finally succeed, I will definitely post a succinct report in the prepublication section.
[Edited on 5-5-2015 by MrHomeScientist]
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Dalis
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| Quote: Originally posted by MrHomeScientist | I don't know what a BaneBot is, but headphone and hard drive magnets are almost certainly neodymium - it's the only type that meets the requirement of
small size and high strength. As diddi said, this is an alloy: Nd<sub>2</sub>Fe<sub>14</sub>B. As you can see, the majority is
iron. If you want to separate out the components of the alloy, it's a hell of a task (trust me). Getting the boron out is easy (dissolve the magnet in
sulfuric acid and it will be left over as a black powder), but separating out the iron and reducing the Nd back to a metal is the tricky part.
See the thread The trouble with neodymium... for all our efforts towards this goal. Right now I have some clean NdF<sub>3</sub> that I plan on
reacting with lithium metal to free the elemental neodymium, using an inert atmosphere crucible I built. I haven't tested it yet, though, so who
knows. Exciting times ahead though!
A possible way to test what you have is to dissolve a piece of each magnet in sulfuric acid. Neodymium magnets will yield a dark purplish solution.
Several of my magnets I tried yielded a green solution, which I suspect (but am not sure) might be the samarium variety. |
Couldn't you just use CaO or chalk instead of lithium? And use a furnace instead of the chamber. Heck is CaO a good reganent for metal seperation? I
have chalk from when I was younger.
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Dalis
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| Quote: Originally posted by MrHomeScientist | The way I did it was to heat the magnet with a propane torch for a couple minutes until it demagnetized (see: Curie temperature), snapped it into
several large pieces, and peeled off the Ni as much as possible. Demagnetizing makes it much simpler to work with. Don't worry if you can't get all
the plating off, since it shouldn't dissolve in sulfuric acid anyway*. The more you get off, the more magnet surface is available to react and the
faster it will dissolve. Warning: dissolving an entire hard drive magnet takes several days in my experience. Heating the solution should of course
speed this up a bit.
*Interestingly, though, I have had instances where the nickel mysteriously vanishes by the time the magnet is fully dissolved
Edit: Dang! Blogfast beat me to it But yes, see the thread I linked for more
info than you ever wanted to know about this process.
If I ever do finally succeed, I will definitely post a succinct report in the prepublication section.
[Edited on 5-5-2015 by MrHomeScientist] |
Nickel carbonile...... It converted to nickel carbonile. As a warning that is VERY toxic. NiCO. I was worried about that. Also couldn't you use a
density column to sperate the Nicklel?
[Edited on 5-5-2015 by Dalis]
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blogfast25
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| Quote: Originally posted by Dalis | [/rquote]
Nickel carbonile...... It converted to nickel carbonile. As a warning that is VERY toxic. NiCO. I was worried about that. Also couldn't you use a
density column to sperate the Nicklel?
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The chances of forming nickel carbonyl (Ni(CO)<sub>4</sub> is as close
to zero as you can possibly get. Where would the CO come from? Even with access to CO nickel carbonyl isn't that easy to prepare.
CaO???? Try to concentrate on getting your magnets to dissolve first.
@MrHS: with reflux at BP (simmering) it's a couple of hours, tops. About 50 % stoichiometric excess of HCl.
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MrHomeScientist
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Geez maybe I need to switch acids...
And then just add potassium sulfate to drop out the double salt (no intermediate steps)? Seems like you'd need more sulfate around for complete
precipitation.
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blogfast25
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| Quote: Originally posted by MrHomeScientist | | And then just add potassium sulfate to drop out the double salt (no intermediate steps)? Seems like you'd need more sulfate around for complete
precipitation. |
You do but it's an inexpensive chemical.
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