plante1999 - 17-1-2011 at 18:20
so i want to know at wath temperature iron nitrate decompose and if it is possible to decompose it to magnetite.
it is for making anode.
thanks!
[Edited on 18-1-2011 by plante1999]
bbartlog - 18-1-2011 at 08:14
Thermal decomposition normally results in a powder, unless the remaining end product is liquid in which case I guess you can get a fused mass. Dunno
what your plan is to make an anode by such processes, though I imagine it's possible; deposit on something granular and make a fluidized bed anode or
something.
Further, in order to get magnetite you need a mixture of oxidation states (+2 and +3), and I believe ferrous nitrate will tend to self-oxidize when
heated, along the general lines of
Fe(NO3)2 -> FeO(NO3) + NO2
So by the time you decompose all the nitrates you would end up with substantially all the iron in the +3 oxidation state, i.e. a bunch of Fe2O3, even
if you started with an appropriate mix of ferrous and ferric nitrate.
It's possible to prepare ferrites this way (CuO + Fe2O3 for example) but I doubt magnetite per se.
blogfast25 - 18-1-2011 at 08:21
A simple procedure for making magnetite as a suspension can be found here. I can vouch that it works:
http://www.sci-spot.com/Chemistry/liqimag.htm
But I’m not sure how you would turn the magnetite precipitate into a solid electrode. Beware of the Curie point: the temperature above which a
permanent magnet becomes… permanently demagnetised…
Magnetite's CP is 585C, so fairly high, perhaps gentle drying (after washing) at 110C, followed by mixing with small amounts of a polymeric binder
(silicone rubber, epoxy resins...) and moulding at 300 - 400C could yield a solid electrode.
What's the end-purpose of the magnetite anode?
[Edited on 18-1-2011 by blogfast25]
hissingnoise - 18-1-2011 at 08:50
ISTR that perchlorates were prepared using magnetite anodes . . .
http://pyrobin.com/files/the%20preparation%20and%20behaviour...