Sulfurization of bleach fix in roller transport

[schlger]

The bleach in my roller transport machine percipitated to sulfur, that covered all surfaces. On accessible surfaces and rolls I can wipe it away but hidden rolls and the pump system is not accessible from outside. Is there a possibility to resolve it by chemicals.

Thanks
Gerhard

 

[Rudeofus]

If it is sulfur, you can try remove it with a mixture of 100 g/l Sodium Sulfite and 10-30 g/l of something alkaline (Sodium Carbonate, Sodium Hydroxide, whatever you can get easily). It will take a while (read: one or two weeks), during which all sulfur contaminated parts have to stay immersed in this soup.

 

[schlger]

It worked! I mixed up a solution of 100 gs sodium sulfite per liter H2O with 20 gs sodium hydroxide and some EDTA 4Na, circulated it in the machine and later also with the inserted roller transport rack, let it rest over night, washed it with water, neuralized it with diluted acetic acid, washed again and the sulfur deposits disappeared. Thank you very much.

 

[Rudeofus]

Interesting link, Cruzingoose! In schlger's case, it seems, elemental Sulfur was the culprit, and this cleans up nicely in sufite+alkali. Silver Sulfide must be pretty hard to clean up, since it is one of the most insoluble compounds out there.

 

[Rudeofus]

I am not surprised to read that neither alkali nor acid would do anything to Sulfur and/or Silver Sulfide. It is, however, possible to convert Sulfur into soluble Thiosulfate by immersing it in sulfite+alkali, and the Kodak document you linked to suggests a way to oxidize Silver Sulfide into something (Silver Sulfate?) which allows the Silver to get fixed away.