Extracting metals from thermite reactions.

[rthmjohn]

I was planning on obtaining some metal samples by extracting them from exotic thermite reactions (ie. vanadium, chromium, nickel). Unfortunately, there really isn't a simple way to prevent the aluminum oxide from entering the molten metal during the reaction. I was wondering if anyone could help me devise a scheme that would allow for minimal aluminum oxide impurities in the metal.

[RyanJ]

I was planning on obtaining some metal samples by extracting them from exotic thermite reactions (ie. vanadium, chromium, nickel). Unfortunately, there really isn't a simple way to prevent the aluminum oxide from entering the molten metal during the reaction. I was wondering if anyone could help me devise a scheme that would allow for minimal aluminum oxide impurities in the metal.

 

Quite hard too do considering how the reaction is required too work.

 

Can't you just work out a way to removethese impurities later?

 

Cheers,

 

Ryan Jones

[rthmjohn]

Any idea of how I could do that?

[RyanJ]

Any idea of how I could do that?

 

I'm not shure.

 

Aluminium Oxide is soluable in alkaline solutions but iron is soluable in acidic solutions so maybe criushing the remains then placing them in something like Sodium Hydroxide will leave the pure iton precipitated out?

 

Liek I said I'm not shure if the Iron will dissolve or not....

 

I'd say crush the mixture, add it to an alkaline solution and see what the results are, anything left at the bottom should be iron though ther will probably be other impurities that need to be removed!

 

Maybe the chemistry experts can provide some insight?

 

Cheers,

 

Ryan Jones

[YT2095]

you need to find comonalities and dissimilarities between the 2 metals and exploit those, sometimes it even comes down to fractional crystalisation, exploiting solubility differences, or maybe even electrolysis and plating out the needed metal. but there`s hope!, if I can split a eutectic mixture of Tin and Lead, your used thermit should be easy

 

without a Specific example, it could be any one or more of a whole list of methods.

[Pleiades]

I don’t know how pure a sample it would get you but aluminum oxide is less dense than all of those metals, it would float on top of the molten metal, this is usually how they remove the metal oxide slag from ore.

[rakuenso]

out of curiosity, what did you use to ignite your thermite?

[rthmjohn]

Let's see... I plan to use the two flower pot method with some Cr2O3 and Al. The reaction will take place within the suspended stacked flower pots and fall through the holes into a pail of sand. The Chromium metal product will have quite a few impurities aside from alumina. i.e. sand and the MgO from the Mg fuse.

[xeluc]

you need to find comonalities and dissimilarities between the 2 metals and exploit those' date=' sometimes it even comes down to fractional crystalisation, exploiting solubility differences, or maybe even electrolysis and plating out the needed metal. but there`s hope!, if I can split a eutectic mixture of Tin and Lead, your used thermit should be easy

 

without a Specific example, it could be any one or more of a whole list of methods.[/quote']

 

Speaking of your tin Experiement, Now that I have a decent power supply, I really want to recreate your experiement. Out of curiosity, looked at the soldering isle in my local harware store and saw lead-free solder that was 95% Tin and 5% Antimony. I bet this would have been easier for you.

[YT2095]

I`m not sure about "Easier" without doing the maths 1`st, but it would Certainly give a much better yield! )

[Ferdinand]

You use two flower pots. I use one and a masonite drill to make a larger hole. Why two flower pots? Instead of sand I have used a bucket of water. The cooling is very quick and spectacular for my students and me! The product iron is brittle of course and not very magnetic -perhaps due to thermal shock cooling and impurities.

 

My wick has been a top layer of KCLO3 and sucrose mix(carefully grinded) with a drop of conc. H2SO4.....but lately I like the use of magnesium ribbon mix...I would really love to know any hints on how I could improve my thermite reaction in terms of ignition, recovery of iron,....Thanks

[RyanJ]

My wick has been a top layer of KCLO3 and sucrose mix(carefully grinded) with a drop of conc. H2SO4.....but lately I like the use of magnesium ribbon mix...I would really love to know any hints on how I could improve my thermite reaction in terms of ignition' date=' recovery of iron,....Thanks[/quote']

 

Personally I just use a magnesium fuse, it ignites easily enough. I suppose you could put an oxidiser in there too make it ignite easier, maybe a KNO3 and S mix would work?

 

As for collecting the Iron, do you want it molten? If not do it over a large bucket of water or preferably an old barh, it should revover the iron without much contamination - just make shure you are no-where near it when it hits that water!

 

Also, search Google, it may turn up some good references!

 

Cheers,

 

Ryan Jones