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Copper dust brightener

We are having copper dust, Which used to turn black. Please provide me some chemical so we can convert the black copper dust into bright & shining copper dust.

Also provide preventive chemical so in future it can not turn black.

Jayesh Trivedi
- India
2007

Your inquiry is a bit vague, Jayesh. We don't know the quantity, the particle size, the alloy, how long it took to get black, where it came from, what contaminants may be on the surface, how long you expect to keep it from blackening, etc.

But a caution is in order anyway. Powder has a huge surface area, so chemical reactions occur much faster than with larger solid surfaces. Chemical reactions involving metal powders can release a great deal of heat and can occur explosively fast!

Generally you need an oxidizing agent like nitric acid or hydrogen peroxide to brighten copper, and benzotriazole ⇦ this on eBay or Amazon [affil links] to keep it bright. But considering the situation you may want to hire a chemist to safely develop a recovery process for you.

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