False positive or platinum in solution?

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JohnGinto

Member
Joined
Jun 24, 2018
Messages
8
Greetings,
I recently processed some materials (around 250 grams)
I have been accumulating them for months.
They are similar to the MLCC but they are the black ones and the one's with the numbers usually (100) or something rather. I incinerated them with a portable butane torch, then crushed them into fine powder.
I gave the material a bath of nitric to see if there are any silver available. Alas silver was present after adding household cooking salt diluted in warm water. (not a lot of silver perhaps close to half a gram if that).
Next I placed the materials into AR with nitric added in increments. I did a Stannous check and gold was present and was precipitated with SMB again yield is minimal.
After filtering I checked again with a Stannous and to my surprise the test result was not what I was expecting.
I expected NO reaction yet the test gave a very dark brown result but never turning black. When I read Hoke's book she said that platinum gives this result with a Stannous test? Did I misinterpret? Could there be platinum in the solution? DMG is way too expensive and out of reach for my budget. Are there alternative methods for dropping Pt?
Please help....
Cheers,
Johno
 
Brown is usually a false positive.

DMG is used to drop palladium, not platinum.

My advice would be to put a piece of copper in the solution to cement any remaining values out, then treat the waste solution. Agitation/stirring is important when cementing to ensure all the solution comes into contact with the copper.

Dave
 
Just be aware that any PGM solution carries major hazards and they are not to be ignored, my advice cement the solution using copper as advised by frugal and make sure you have decent protection and a decent hood, if not don’t mess with PGMs the risks are huge and irreversible.
 
"The black ones with numbers on" are resistors. Some contains ruthenium or osmium dioxide. Both can form very volatile and toxic tetroxides. The toxic and volatile nature of ruthenium tetroxide is so high that it is delivered in glass ampoules that are opened in a fumehood. If you are exposed to ruthenium tetroxide it attacks the eye by depositing metal on top of your eyes and makes you go blind.

Göran
 
FrugalRefiner said:
DMG is used to drop palladium, not platinum.

I got a bunch of platinum from my DMG-dropped palladium. Lou said that DMG will drop platinum with the palladium, and that this fact is not well known. After dissolving the yellow DMG precipitate, with nothing else in with it, I added saturated ammonium chloride. Not expecting any Pt to form, I was very surprised to see it precipitate much fine grain platinum salt. To see it happen, go to the 5 minute point in this video;

https://www.youtube.com/watch?v=IE23cbEoWAU

kadriver
 
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