Mixed smd components

[solarnevo1]

I have 550 gr of mixed smd small capacitors, resistors, etc... Any idea how to recover gold, silver and paladium from this mix? My idea is to wash first whole lot in hcl to didolve tin. Then melt everything with some coper. And after melting process a melted button. Is that good way to go?

 

[canedane]

I have never recover pm from a lot like yours, if it was mine i will find a mesh to take away the solder balls.
Then i will take the most magnetic stuff, after that i will take the less magnetic MLCCs.
Just an idea to make the recovery more simple?
Henrik

 

[patnor1011]

You may also want to take away all those yellow coloured Ta capacitors. Look for the same size and shape in black - they are Ta capacitors too and there is nothing of value in them apart from Ta.
Also you do have some small tiny IC there - those with 3 legs on two sides. They need to be processed like IC.
From the look of it if you take out what I pointed you may reduce your pile by about 1/5th.

 

[Shark]

If the Ta caps were removed, would the rest be a candidate for cupeling, then refining the resulting button?

 

[solarnevo1]

It will be a nightmare to hand pick caps. Maybe mesh but any other idea? Hcl for solder balls should work fine. If I get rid off solder with hcl what would be next step? Is it possible to use copper or silver like collect metal and process a button?

 

[goldenchild]

With all that steel in there the HCL probably won't work like you think it will. And boiling the ceramics will probably turn them into mush. So at the end you'll have a huge mess of ceramic powder and undigested metals. No base metal if you're lucky. If it were mine I would smelt it all. But that comes with it's own problems and also not so easy to do.

 

[solarnevo1]

After some investigation I have another idea. Will try this process. First I will smelt everything in mix with some lead and some silver. After smelting will try cupellation to get rid of base metals. After that process I should have a nudget of silver, gold, and some palladium. Disolve it in hno3 use hcl for silver and try to cement palladium with copper. Residues in AR and dropp the gold. Any suggestions or some other idea?

 

[patnor1011]

Just one. Do not be scared to sort out your material. While it looks like time-consuming it will make your process faster in the end as there is no point having tantalum capacitors in a mix and if you take them out there is 10-15% less of material to process.
Like we used to say here: Garbage in - garbage out.

I sorted about 20 kilograms of such material. Use different size sieve - I used 3 and was left with pretty homogenous material which I then spread on the table and started to pick out one type of stuff. Go by type, size, colour... When I picked out all crap I was left with just capacitors and resistors.

The better you prepare your material the better the process and result will be.