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Neutralize silver coated item taken out from cyanide solution

Hello,

Can we dip silver plated item in calcium hypochlorite or sodium hypochlorite, in order to neutralize them
I will be using KAg(CN)2 solution for plating.

Thank you

Vikrant A. Chaudhari
student - Mumbai, India
2007

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No! You must carefully rinse the parts in water until there is no sign of cyanide. Then, when you absolutely are sure there is no entrapped cyanide, you can dip the part into a very dilute (maybe 1 percent) sulfuric acid under good ventilation.

The rinsewater can be treated with sodium hypochlorite to destroy the cyanide, again with good ventilation. However, cyanide is a terribly dangerous solution for a student to be using and the fact is you should not be asking these questions because you should not be attempting these procedures until you have received hands-on training from an experienced party. The cyanide solution is poisonous of itself, but it will also release deadly poisonous hydrogen cyanide gas if acidified.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007