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Solubilities of metal precipitated with DTC (dimethyl dithiocarbamate)

I am interested in finding the solubilities of heavy metals in the presence of DTC, particularly trivalent chromium, silver, selenium and tin. I understand that the metal precipitates formed in the presence of DTC are NOT sulfides, so it is reasonable to assume the solubility of the precipitates differs from that of the corresponding metal sulfide salts. Chemical vendors that I am working with have not offered solubility data or stated what can be achieved with DTC and similar organic sulfide chemistries.

Robert D. Edelman- Environmental/Process Engineer
- Bedford, Massachusetts
1995

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Hi, Robert.

DeGussa offers TMT-15, another organic sulfide, and their literature includes a sprinkling of test results.

"Heavy Metal Removal Using Dithiocarbamates" by R.E. Wing and W.E. Rayford (Plating & Surface Finishing, Jan. '82) has some useful data too.

Ironically, Tom Pullizzi and I were involved just this month in a treatability analysis for nickel mixed with a soak cleaner, and we found sulfides and DTC worthless for this particular mix. Low pH chelate-breaking was the only thing that worked.

After the massive fish kill in the White River in Indiana, allegedly caused by grossly excessive DTC use in the plating shop of a car manufacturer, please be very careful with DTC and seek substitutes if possible. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey