Sciencemadness Discussion Board - Ammonium Ferric Oxalate

Ammonium Ferric Oxalate

dann2 - 21-12-2007 at 12:51

Hello,

Can anyone suggest how I might obtain Ammonium Ferric Oxalate from some of the more 'mundane availables'?

Cheers,

Dann2

12AX7 - 21-12-2007 at 13:14

Dissolve ferric oxide in oxalic acid. Neutralize ammonia with oxalic acid. Mix solutions, then grow crystals.

Tim

dann2 - 21-12-2007 at 13:32

Hello,

Thanks Tim, can get Ferric from heating Ferrous Sulphate.
You can purchase Oxalic acid from decorating shop, forget what they use it for.
Have Ammonia.

Attempting to make Magnetite anode with Ti substrate BTW.
Cheers,
Dann2

not_important - 21-12-2007 at 13:52

The Encyclopædic Dictionary of Photography
By Walter E. Woodbury
Published 1896
The Scovill & Adams company

FERRIC AMMONIUM OXALATE (Formula Fe2(NH4)2(C2O4.. Synonyms, ammonia oxalate of iron).—Occurs in green very soluble crystals which should be kept in the dark as when exposed to light they become more or less oxidized, which fact is made use of in the " blue " or cyanotype and the platinotype processes. It can be prepared by dissolving 3 ounces of oxalic acid in 8 ounces of water, raise to 100 degs. C., and saturated with moist ferric hydrate, avoiding excess. Filter the solution thus obtained and neutralize with ammonia, filter and evaporate to dryness at 100 degs. C.

Xenoid - 21-12-2007 at 14:53

@ Dann2

Ferric oxide is usually available from pottery suppliers and is also used extensively for colouring concrete. Most companies that do "fancy" concrete work, such as imprinting and colouring should have it.

You may find the oxalates fizz up a bit when heated. I've experimented with plain tartrates for Sb and they almost foam, and would leave a very uneven coating!

dann2 - 21-12-2007 at 16:23

Hello,

I am working along the lines of here:
http://www.geocities.com/CapeCanaveral/Campus/5361/chlorate/...
I have already tried this with a coating of Fe on Ti and heated at about 1000C for about 3 hours with steam.
The Ti sagged!!
I obtained three bend 'anodes'. The were completely passivated whit a bright yellow Ti oxide where there was no Iron. Where there was Iron it had turned to Magnetite (I guess it was magnetite) with a layer of the Ti oxide underneath.
Temp. far too high. Will try at lower temp., with FAO if I get around to making it.

Dann3

[Edited on 22-12-2007 by dann2]

dann2 - 26-1-2008 at 16:09

Hi,

Quote:

Originally posted by not_important
The Encyclopædic Dictionary of Photography
By Walter E. Woodbury
Published 1896
The Scovill & Adams company

FERRIC AMMONIUM OXALATE (Formula Fe2(NH4)2(C2O4.. Synonyms, ammonia oxalate of iron).—Occurs in green very ..............

Is this formula quoted correctly. I fing on the web that it is:
(NH4)3Fe(C2O4)3:3H2O

Also what is Ferric Hydrate?
Can't seem to find a compound as such. Is it a hydrated Ferric Oxide as per this:
http://www.springerlink.com/content/n2r7515232686537/

TIA,

Dann2

[Edited on 27-1-2008 by dann2]

chemoleo - 26-1-2008 at 19:02

Not sure 12AX how that would work with Fe2O3, it is not exactly well soluble in anything...

You could start from Fe(OH)3 instead.

At LS, see http://www.lambdasyn.org/synfiles/kaliumtrioxalatoferrat.htm , bottom procedure using FeCl3.

This is for the potassium salt but I'm sure this could be employed with ammonium oxalate too.

I.e. 5.3 g (19.61 mmol) iron(III)-chloride-Hexahydrate in 8 ml H2O is added to a warm solution of 12 g (65.13 mmol) potassium oxalate-Monohydrat in 20 ml H2O. The solution is cooled to 0 °C and kept at this temp for crystallisation for a while. The crystals are redissolved in 15 ml warm water and recrystallised. Yield 6.4 g, 66% of theory.

[Edited on 27-1-2008 by chemoleo]

dann2 - 17-2-2008 at 11:06

Hello,

The Fe2O3 would not dissolve in the Oxalic acid when cold. I decided to reflux to see and most of it dissolved. I then added twice the stioci amount of Oxalic and all Fe2O3 dissolved. Perhaps if I refluxed longer with the stioci amound to Oxalic it would have all dissolved without adding a second amount of Oxalic. I refluxed initally for about 12 hours.

I am going to try to make the FAO using Ferric Chloride, Oxalic and Ammonia (second time round!). I already tried and it seems to be OK but I made a mistake and added far too much Ferric Chloride.

Dann2

not_important - 17-2-2008 at 23:37

Quote:

This is for the potassium salt but I'm sure this could be employed with ammonium oxalate too.

Check the respective solubilities, the ammonium salt may be sufficiently more soluble to reduce the yields. Data I have shows NH4 at 5 to 10 times more soluble than the potassium salt.

[Edited on 18-2-2008 by not_important]

woelen - 18-2-2008 at 00:19

The potassium salt is much easier to prepare, because of its much lower solubility. The ammonium salt can easily be obtained from multiple arts and photography sellers and hardly is worth the effort to make yourself. I have 100 gram of the salt:

This stuff can be purchased (it is not expensive) from http://www.artcraftchemicals.com and it is not a hazmat chemical. It can be shipped worldwide at low cost. I have my material also from this seller. I indeed use it for cyanotype-like processes and experiments. It works better dan citrate-based chemicals.

Edit(woelen): Made link to picture working again.

[Edited on 30-7-16 by woelen]

Nitrous2000 - 16-1-2016 at 18:46

Quote: Originally posted by dann2

Hi,

Quote:

I believe ferric hydrate is also known as ferric hydroxide.