Can we get a concensus of opinion as to the reaction between
the cyanide, peroxide, and water as to what you have remaining
after the bombing?
I’m not a chemist, remember, so I’m just repeating what I’ve
been told. The peroxide oxidizes the cyanide to cyanate, and in
the process the gold cyanide complexes formed when there was
still free cyanide dissolving gold are converted back to metalic
gold (why the formerly clear solution is brown after the pop).
Whether there remains any free cyanide depends on the amount of
peroxide used, and how long it is allowed to sit together after
the main reaction. I’ve always assumed that some unreacted
cyanide would likely remain. Safer to treat it that way.
At the jewelry company I work for, we collect the remains
and send them to the refiner with the other suitable material,
although I have also worked at companies where it went in the
Unless you do only very little, it’s usually worth retaining for
refining. Evaporate the waste down to a sludge to save space.
I know that there are some serious EPA fines if you get caught
doing this, and as a personal opinion, I don't think that
anything this potentially dangerous should be disposed of in
such a cavilier manner.
Agreed. Cavalier is the wrong way to treat this stuff. And the
EPA doesn’t make exceptions based on quantity I’d guess, though
they’ll not likely catch the folks doing one small batch every
month or two.
Nevertheless, it’s appropriate to note that cyanide does indeed
occure naturally in nature, and in SMALL highly diluted amounts,
does little if any harm. The problem comes when every jeweler is
a building full of them has the same attitude with their own
twice weekly bombing process. With all the folks in the complex
doing the same thing, the sewage system is no longer getting
just an occasional trace of the stuff. It’s getting pounds of
cyanide per week. And THAT is not trivial or harmless.
I hear of a non-cyanide bombing coming from Italy, but Shimon
can't find out anything in Vicenza- it would be great if it
works as well as the cyanide process, huh?
Yeah. but don’t hold your breath. They said the same for the
thiurea based non cyanide electrostrip solutions that PM and
others sell. They do work, but they sure are harder to get to
work well, in my experience. Plus, the sulphur smell is harder
(at least for me) to tolerate than the alkaline one from
bombing. And to date, I’ve not heard of a non cyanide bombing
process. let us know on the list, will you, if you hear more on