A Modern Method for Manufacturing Ferric Oxalate

Oranges

A
Oranges

  • 4
  • 0
  • 89
Charging Station

A
Charging Station

  • 0
  • 0
  • 82
Paintin' growth

D
Paintin' growth

  • 3
  • 0
  • 80
Spain

A
Spain

  • 5
  • 0
  • 76

Recent Classifieds

Forum statistics

Threads
198,117
Messages
2,769,889
Members
99,563
Latest member
WalSto
Recent bookmarks
0

Ian Leake

Subscriber
Joined
Mar 25, 2005
Messages
1,628
Location
Switzerland
Format
Analog
This post is for people interested in making their own ferric oxalate for platinum/palladium printing.

Most people buy their ferric oxalate from one of the specialist photographic retailers. However, I find that the best ferric oxalate is the one I make myself.

I have been working on a better way to make my ferric oxalate. It's much easier and less messy than the traditional process used by Pizzighelli and others. So far I've had very good results, with some of the best blacks I've ever made.

This process is not new to science, but doesn't seem to have made its way into the photographic community. It is based upon US Patent 1899674: “Process for the production of ferric oxalate” filed by Leo Curtin in 1933 and now expired. A more complicated version of the process was published by Dick Stevens in Making Kallitypes (1993). Stevens' process produces sulphuric acid as a by-product, so really is not suitable for small scale production.

In summary, you add oxalic acid then hydrogen peroxide to iron(ii) oxalate in water. It's easy, clean, and makes high quality ferric oxalate.

Full instructions are here on my website: https://www.ianleake.com/pages/a-modern-method-for-manufacturing-ferric-oxalate
 

simongg

Member
Joined
Mar 1, 2023
Messages
2
Location
Canton
Format
4x5 Format
I found another table online that corresponds to the specific gravity and content of iron oxalate. It's different from yours. Which one is correct? thank you.
 

Attachments

  • IMG_0071.jpeg
    IMG_0071.jpeg
    28.4 KB · Views: 14
OP
OP
Ian Leake

Ian Leake

Subscriber
Joined
Mar 25, 2005
Messages
1,628
Location
Switzerland
Format
Analog
I found another table online that corresponds to the specific gravity and content of iron oxalate. It's different from yours. Which one is correct? thank you.

They're both correct, but measure different things. If you base your %wbv calculation on the commercially available dry powder, then you aim for about a 27% solution. If you base it on the actual iron(iii) oxalate content then you aim for about a 20% solution. The bottom line is to aim for a specific gravity of about 1.18 and then be consistent.
 
Photrio.com contains affiliate links to products. We may receive a commission for purchases made through these links.
To read our full affiliate disclosure statement please click Here.

PHOTRIO PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Ilford ADOX Freestyle Photographic Stearman Press Weldon Color Lab Blue Moon Camera & Machine
Top Bottom