giant monolithic capacitors on motherboards.

[pimpneightez]

Anybody know if there are any PM's in these? This is from an apple g5. It has giant capacitors on each side and was built circa 2004.

 

[patnor1011]

Easy to find out. Crush 2-3, put in nitric heat for a while and test for silver and for Pd. I would say that Ag will be there for sure.

 

[pimpneightez]

That sounds like a plan! definatly has some mass to it thanks alot. Feels like some silver

 

[Marcel]

There are usually only 2 metals beeing used for those capacitors as electrodes, palladium an nickel. Since nickel can be magnetized, use a neodyme magnet and see if they get attracted. If not there should be Pd in them. These capacitors are not small but not giant :lol:
These are the standard sizes:

(MLCC) SMD-Ta-Chips1) SMD-R-Chip

Type metric L W in mm

0201 0603 0,6 0,3 X – X
0402 1005 1,0 0,5 X – X
0603 1608 1,6 0,8 X – X
0805 2012 2,0 1,2 X R X
1020 2550 2,5 5,0 – – X
1206 3216 3,2 1,6 X A X
1210 3225 3,2 2,5 X – X
1218 3146 3,1 4,6 – – X
1225 3164 3,1 6,4 – – X
1411 3528 3,5 2,8 – B -
1808 4520 4,5 2,0 X – –
1812 4532 4,5 3,2 X – –
2010 5025 5,0 2,5 – – X
2220 5750 5,7 5,0 X – –
2312 6032 6,0 3,2 – C –
2512 6330 6,3 3,0 – – X
2917 7343 7,3 4,3 – D –
2924 7361 7,3 6,1 X – -


@Partnor: How would you test for silver?

 

[Geo]

a drop of hcl in the solution will produce i white cloud if silver is present.

 

[pimpneightez]

They are magnetic I guess that's not good. should I still keep them? they are kinda cool and make pretty designs in the glass jar.

 

[samuel-a]

They are magnetic I guess that's not good. should I still keep them? they are kinda cool and make pretty designs in the glass jar.

Do not rule out anything just by testing with a magnet.
I have processed lots of magnetic MLCC's that yielded Ag, Pd and Pt.

Do the test Pat had suggested.

 

[patnor1011]

Do NOT throw them away. As far as I know all of them contain nickel and silver. If I only find thread with pictures and msds....
Some of them contain palladium.

Crush few, boil in HNO3 for a while and test with dmg for Pd and HCl for Ag.

 

[pimpneightez]

sounds good. I can't test until next week. I'll keep you all posted.

 

[Marcel]

Never throw them away, of course. As it has been said nothing can be ruled out.
But you can say that those that are affected by a magnet contain a lot of nickel. I have noticed that those are mostly the capacitors in low-cost elecronic circuits in notebooks and PCs.
It would make sense for them to be nickel-based. Maybe someone will make a comparative recovery one day and we will see how big the difference is. The nickel may also be part of the terminals.
If you collect MLCCs dont forget the chip capacitor networks or arrays !
They look like this:

The are often found close to interface connectors on the boardside where they replace multiple single MLCCs. But internally they are just the same.
not to be confused with chip resistor arrays (see below):

which may also contain Pt, but thats a different story.



@partnor: A very good source ofinformation on MLCCs in english: http://www.johansondielectrics.com/...training/jdi_training-mlcc-basics_2008-01.pdf

 

[pimpneightez]

Nice! I opened a photo copier and took out a board that has some nice gold plate on one side and on the other it's full of those chip resistor arrays. same exact one pictured in your post. There are about 100 on each board and I pulled two boards out. They are real small but have to be taken off anyway to reclaim the gold plate on the back. I'll take a picture later and post it when I get home from work.

 

[pimpneightez]

So I tested the capacitors and found silver-negative nickle-positive and palladium-unknown(I had no way to test for palladium)

 

[patnor1011]

Stannous or DMG both are good tests for Pd.

 

[pimpneightez]

I didn't have any Stannous and I used the dmg to determine there was nickle (I got a rose colored solution). I think it was DMG anyway. I used and old flow chart for testing nickle alloy. There were about 5 steps involving decanting, precipitating,nitric,hcl and a base to get the PH right. Is testing palladium easier than that? Can you just put the DMG straight into the nitric after the capicitor is digested? what color should I expect orange?

 

[patnor1011]

Check my post in my signature, there are pictures on how I tested for Pd with DMG.

 

[xALmoN]

so there is a high chance of all these monolithic caps having silver in them?

maybe i should look out for them too, i like silver more than gold. because they look prettier to me.

 

[galenrog]

I want to thank Marcel for the illustration posted from Johanson Dielectrics. Although my assumption is that higher end electronics are likely to use PME rather than BME, plus older systems, nothing can be left to chance. Because there are multiple layers on the electrodes for monolithic capacitors, a simple test with stannous or DMG may not tell the whole story. Looks like I may have to incinerate a batch, digest all metals, then test for and recover metals one at a time. I'll look into it once i have a KG or two so I can test different methods for recovery.

 

[g_axelsson]

... Looks like I may have to pyrolize a batch, digest all metals...

It is not pyrolyze, it's called incinerate to oxidate off all carbon and carbon compounds. As a bonus we also evaporate any acids in the material.
http://en.wikipedia.org/wiki/Incineration

Pyrolyze is to heat without oxygen and converts carbon compounds to pure carbon and gases.
http://en.wikipedia.org/wiki/Pyrolysis

Please, let us use the proper terminology here.

/Göran

 

[galenrog]

Thank you for the clarification. While familiar with enough mining terminology to be understood by other small scale miners, I do get terms confused in the area of refining and processing to that end. Edit has been done.

 

[voeckel]

Reviving an old thread for those who deal with MLCCs.
Adding some information regarding coding of MLCCs and their PMs. Might be helpful as reference in case you have full codings at hand. :idea: