RE: EDTA TETRASODIUM

Ryuji,

> I have a question about using EDTA Tetrasodium vs. EDTA Disodium to clear
> palladium and kallitype prints.
>
> Specifically, the tetra when in solution creates a base solution. Can I
> acidify the solution with say sodium metabisulfite and expect it to work
> effectively as a clearing solution?

>>
As long as you keep the fixed molarity of EDTA and sulfite/bisulfite,
and also fix the solution pH, you can arrive at the same solution by
mixing (1) disodium EDTA and sodium sulfite, or (2) tetrasodium EDTA
and sodium metabisulfite. In reality, I think you can use the same
molarity of EDTA and adjust the amount of metabisulfite to reach the
target pH.

>>

Thanks for the info. After posting my question to the list I found a recent
post by Clay Harmon on photo.net that answered my my question:

To use EDTA - tetra sodium in place of di-sodium for clearing the following
recipe may be used:

1 tablespoon sodium sulfite
1/2 teaspoon sodium metabisulfite
1 tablespoon EDTA tetra sodium

Add to water in the order listed above to make 1 liter.

Don Bryant
  
Received on Sun Apr 2 19:46:38 2006