Any PM in these yellow, I think capacitors?

[Slochteren]

Are there any PM's in these? I tried burning them and grinded them, and boiled them in Hcl, that made a mess. I have over 3 kilo of them and before collecting more I would like to know if there is any recoverable value in them. They come from boards late 1980.

Thanks Paul

 

[eaglekeeper]

There's a possibility the little yellow square components contain a MLCC. Carefully snip one of them open from the sides to break away the plastic. I think the small orange ones with the red strip is Tantalum capacitor.... I'm not sure about the longer orangish ones if they contain PM's or not.

 

[Slochteren]

They contain mlcc's non magnetic, also should contain Palladium and silver. I never processed palladium and not sure I want to. Anyone who wants to refine them for me?

 

[eaglekeeper]

They contain mlcc's non magnetic, also should contain Palladium and silver. I never processed palladium and not sure I want to. Anyone who wants to refine them for me?

I've never processed then either, I've just been collecting them for years. I have a picture that shows some other components that contain an MLCC, but I have to find it.

 

[RichardSukhoi]

They contain mlcc's non magnetic, also should contain Palladium and silver. I never processed palladium and not sure I want to. Anyone who wants to refine them for me?

Fine wire wound or etched thin line resistive temperature transducers (often 100 ohms at room temperature) are typically platinum. The amount of metal on the vapour film ones is trivial but the wire wound ones can have reasonable amounts. The thicker wire devices that carry more current when in use are typically encapsulated in bososilicate glass and the wire is ribbon shaped. The flat rectangular ones using a wire are typically wrapped over a ceramic (aluminide) wafer, or a fiberglass and resin board. I am sure people here would have a proper method for each. A guess by me would be HF acid for the borosilicate glass pack, pyrolysis followed by mechanical for ceramic, and ozone ashing for fiberglass and resin (leaving fiberglass and platinum).

 

[orvi]

DO NOT LEACH THEM IN ACID!

This will create unbelievable mess of partially dissolved ceramics and metals in solution, nearly impossible to filter and wasteful in terms of chemicals. Not to mention you will put PGMs in solution, which require some extra caution since they are potent allergens and sensitizers.

If you want to process them, get rid of the plastic (by incineration or some mechanical treatment), then etch the solder in plain HCl, dry the caps thoroughly and smelt them.

I created a thread in the past where I disclose whole process in detail. In this case of more modern ones, use boric acid as flux, not silica.

https://goldrefiningforum.com/threa...cs-disclosed-process.31895/page-2#post-340495