Gold Content of Scrap Items Series: Slotted CPUs

[qst42know]

If only to have NASA's budget. :mrgreen:

I hope you find some to try however it remains to be seen if this elusive solvent could be cost effective.

 

[bagus]

The brown epoxy chips contain only traces of gold per pound. The only feasible way to recover the gold would be grinding and leaching or incineration followed by leaching, but keep them separate form the green ones.

The capacitors are the tiny tan-brown colored rectangles mounted on top of the cpu around the heat spreader.

Steve

so the capacitor is in the brown cpu right? because I can't find it in the green cpu

 

[lazersteve]

The red boxes show the capacitors on the green fiber cpu:

Steve

 

[glondor]

Hey Lazersteve, did you ever quantify the values in the P3's slot card and CPU after the fingers were off?

 

[lazersteve]

Nothing scienctific yet. I have found that it is best to dissolve out the solder from the through holes then separate the epoxy center section from the laminations of the green fiber cpu.

The epoxy section is then crushed and leached or panned for the gold wires.

Incineration of the epoxy central section makes crushing easy as pie. Avoid the toxic vapors that emit from the burning epoxy.

Steve

 

[glondor]

Do you incinerate these your self Steve or do you have a place that does if for you.

 

[lazersteve]

I've incinerated a few small samples as a test to see how the epoxy would react. Nothing on a scale larger than a few pieces.

Steve

 

[Militoy]

We manufacture potted electronic and electromagnetic assemblies, and occasionally need to remove epoxy potting compounds to perform destructive physical analysis (DPA), or repair. I've found most modern cycloaliphatic epoxies to be fairly impervious to MEK - that's even one of the standard solvents used in the resistance-to-solvents test. We soak in a commercial paste-type paint stripper to soften the epoxy into mud - and dig out the epoxy by hand. I believe on a commercial level - crushing / grinding and incineration is likely to be the most economical method.