Help.. lost formula Potassium oxalate

[dpurdy]

Hey people, a few years ago I downloaded a formula for making homemade Potassium oxalate solution. I believe it called for oxalic acid and perhaps potassium carbonate. I made a batch and it was very easy to do and I ended up with a gallon of the developer for my platinum printing. I kept the formula on my computer but now that I need to make another batch I can not find it and I can't find it on line either. Does anyone by chance know how to make it?

I mean make it from scratch, not mix it from powdered potassium oxalate.

 

[dpurdy]

Never mind.. I finally found it... took me a couple hours to track it down.. here it is. I did it before and it works great.
Materials:

• Distilled water – 4 liters (~ 1 gallon)
• Potassium carbonate – 908 grams (2 pounds)
• Oxalic acid – 794 grams (1.75 pounds)
• pH paper (litmus paper) or a pH meter

To make 4 liters:

1. Start with 2.5 liters of distilled water at room temperature.
2. Add 908 grams of potassium carbonate with stirring until dissolved.
3. Weigh out 794 grams of oxalic acid (this fills a 1 liter beaker about 3/4 full).
4. Add oxalic acid about 1/4 cup at a time and stir until bubbling stops, then add another 1/4 cup, repeat until all has been added or until there is no further bubbling.
5. Using pH paper or meter, check the pH. It should be about 7.0 (neutral) at this point.
6. Top off with distilled water to make 4 liters.
7. Add about 60 grams more oxalic acid, check pH again.
8. Add more oxalic acid if necessary until pH is below 6.0.
9. If you find additional oxalic acid will not dissolve, stop.
10. Filter to remove any debris and transfer to storage bottle.

 

[Donald Qualls]

Nice!