YT2095
International Hazard
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an alternative Magnetite route.
rather than using the commonly known FeCl3 method, I`m going for an alternative route.
you need only 2 readily available chems for this, Iron Sulphate (FeSO4) that you can get from almost Any gardening store as Moss killer for lawns,
it`s also pretty easy to make if you wanted to.
and simple Washing Soda (Na2CO3), if for some bizzare reason you can get this then use baking soda that`s been heated to a high heat for a while, this
will convert it to washing soda also.
here:
washing soda on the left, iron sulphate on the right, I recrystalised the iron sulphate myself from Moss killer.
dissolve an equal weight of each in water, now I know that a mole of iron sulphate is a little heavier than a mole of the soda by about 10 grams, but
we want the carbonate in excess and also to keep the method simple.
mix both solutions whilst stirring well, it will Instantly make a horrible gray/green "Mud" and thicken up a little too, this is normal, keep mixing.
when it`s all mixed feel free to add more water and mix really well, leave it to stand now and you`ll see the "Mud" start to settle to the bottom
leaving a murky liquid on the top, pour this liquid off carefully so as not to lose any "mud".
keep doing this at least 4 times, making sure you wash out as much of the soluble sodium sulphate as you can.
now you need to filter this "mud", a plain coffee filter is ideal for this, it`ll catch all the Iron Carbonate (Mud) that you`v made and get rid of
what should be just water by now.
keeping it in the filter paper put it somewhere to dry out, on a sheet of plastic out in the sun is fine.
when it`s dry it will crumble very easily and look just like Rust powder.
you Now have to heat this up very hot to decompose the carbonate, I used a crucible and bunsen burner:
the carbonate is on the left, in the crucible is now the impure Magnetite!
you`ll notice during heating that the Brown rusty carbonate will go Black during heating, this is normal, keep heating and keep the lid ON during
this, don`t allow too much or any Air to get in, if you do you`ll end up with an impure product.
let it cool naturally now (do try to make sure it`s cool before touching it!) it`ll take on a deep red to black color as shown (it`s a bit more red as
I took the lid off to watch so I could give you more data).
congrats, you`v just made a load of Magnetite
a simple test with a magnet:
a little bit on the RED side, but I`ll provide a further pic of the pure Black stuff.
yes, you`ll notice the magnet is in a plastic bag, how else would I get it off the magnet if the powder decided to cover it!
here`s what it Should look like when you`re not tempted to take the lid off during the reaction:
as you can see the stuff even sticks to the spatula that isn`t even Magnetic, at least it Shouldn`t be.
how it should look with the lid on, and an idea of the heat used:
but don`t worry if you don`t have a crucible, here`s another method that works just as well!
you can use the lid off another tin can for a cover, but Do burn off all the plastic and paint coating 1`st.
and for Completeness here are All the iron compounds featured and mentioned in this thread:
it gives a nice idea of Color.
my hypothesis as to Why it works:
since Fe2O3 is a a 70:30 ratio of iron to oxygen and Fe3O4 is a 72.3:27.6 ratio.
the the Fe3O4 is favoured in a reducing atmosphere, whereas the Fe2O3 would be in a Less reducing (or more Oxidising) atmosphere.
which would bear out my latter experiment of mixing all the oxides on that paper with carbon dust and reheating to leave a very magnetic black powder.
I predict that heating this again with the lid OFF will result in a Red powder of Fe2O3.
in fact my results do show this, in the 1`st batch I made where I took the lid off to observe and ended up with a redish powder, but had the Black
powder when I didn`t take the lid off to peek, And the black powder is Intensely magnet sensitive whereas the redish attempt (peeking) is only
marginal.
Also I can safely factor in that my Propane bunsen isn`t anywhere near hot enough to effect either Fe2O3 or Fe3O4 directly with heat alone, but needs
the chemical reduction/oxidation to make them change.
Also on a NASA site I read that iron carbonate will form magnetite on thermal decomp or high power mechanical shock (like an explosion or the likes).
Other than that, I really have no Exact idea of how or Why it works.
But after doing a little more research it seems that my Hypothesis is correct, you can quite easily reduce Fe2O3 to Fe3O4 using H2 and/or other
organic substances at temps ranging 270c - 600c.
furthermore you can reverse this by Oxidation at similar temps.
scroll down to figure 3.15 in this doc: http://books.google.co.uk/books?id=extQfrcDveYC&pg=PT120...
and to test this, I have that pure Fe2O3 here that isn`t at all magnetic (not even with a NIB magnet) and have mixed that with a little powdered
carbon and heated that in a closed crucible.
result: Jet black highly magnetic Powder, as predicted.
Edit: I`v since learned that what I assumed was FeCO3 is in all probablility, likely to be Fe(OH)CO3.
and not the pure carbonate as I thought.
[Edited on 16-6-2008 by YT2095]
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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chemoleo
Biochemicus Energeticus
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Registered: 23-7-2003
Location: England Germany
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Very nice, YT.
It's kind of obvious now that you say it, but never thought of it - you are starting from Fe2+ , so with a lack of oxygen you'll get FeO and Fe3O4...
?
from wiki: 'Iron(II) oxide (FeO) or ferrous oxide is also known as wüstite in its mineral form. As a powder this black oxide can cause explosions as
it readily ignites.'
I guess you didn't observe this...!?!
Would be interesting to see what happens with total exclusion of air. Would CO form as well, next to CO2? Perhaps it might be interesting to feed the
gas output into and ammonical solution of CuCl (proof for CO). Or better, this might be a good method for making CO.... if magnetite forms even in the
total absence of O2.
Btw - did you ensure that no Na2SO4 is present? I bet there'll be a fair bit left in your precipitate, and resultant oxide...
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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YT2095
International Hazard
Posts: 1091
Registered: 31-5-2003
Location: Just left of Europe and down a bit.
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nope, there were no explosions or sparkles seen at all in the 1`st trial when I kept taking the lid off to look inside, as for total air exclusion,
the best I got with such a simple set-up was to tamp down the carbonate into the crucible really hard so it resembles something you find in a makeup
kit like eyeshadow and put a layer of carbon powder on top of that, replace the lid and then heat.
when it`s done the carbon powder just blows off quite easily, leaving a compact black magnetic material, and there are shiny bits in there too, almost
crystaline.
as for the Na2SO4 I did wash my ppt 5 times over a 12 hour period with 4x the volume of water as ppt per wash.
I made sure it was stirred well for each wash and then allowed to settle.
I suppose you could always use a little barium chloride to test for sulphates in the wash water just to make 100% sure.
although I washed the Magnetite products after making them to remove any carbon powder that may still be unreacted, I expect that would also remove
some sodium salts if any remained.
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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