Non-Chemical processing ceramic cpu's commercially in Manila....

[Harold_V]

Thanks for the clarification on cupellation, Chris.

Aside from having done a little with a torch, I never got involved. I did no assaying in my years in the refining business. I relied on the expertise of local assay labs, all of which are now defunct.

Harold

 

[Redders]

Ok Mike, hereunder is the complete procedure for recovering Au from processors as I have observed:



STEP ONE

1) break the processors (cpus) into smaller pieces (not too small) with a hammer. Make sure you can collect even the tiny pieces .

2) The minimum ideal quantity is about 10 kgs of processors; once all broken up, put in a clean container, separating the “gold plated lids” from the other broken pieces;

3) use a crucible (in the Philippines, made of clay, oblong shape, approx 30 cm x 40 cm), sit it on a bed of sand, heat it up, using fire from two separate tubes, one dispensing kerosene and

the other tube dispensing air from a compressor. Once lit, the resulting fire can be controlled by the amount of air coming out of the tube; the fire should be from the

top of the crucible;

4) put powdered “borax” (handful will suffice) into the crucible; then put about 3 kgs of processors, then add 10 kgs of lead (for easy handling, the lead are either pellet size or washer size.

It doesn’t really matter what shape or size because in the heat, the lead will melt quickly;

5) mix every now and then for about 30 minutes to 1 hour, observing if the metal pins or legs underneath the processors have melted;

6) remove the “ceramics” from the crucible using a metal bar hook-shaped. Fish the ceramics slowly so the molten metal stays in the crucible;

7) add another 3 kgs of processors, and repeat the process, until all the processors are done;

8) the above procedures are done while the heat is constantly on;

9) when the last of the processors’ ceramics are removed, as well as any slag on top are removed, keep mixing while maintaining the fire;

10) let the mixture settle (while the heat is still on) for about 5 to 10 minutes;

11) using metal tongs, slowly tip the crucible, allowing a tiny amount of molten metal, out. Additionally, to continue the flow out of the crucible, use the metal bar, tap lightly into the liquid metal, allowing it to flow out of the crucible.

12) Turn off the fire (kerosene), but not the air. The result is a gust of smoke containing lead gas. After about 3 minutes, light the fire again. Max heat the molten metal. At this stage, the center of the molten metal will have a different color from the surrounding liquid. The center will have a light yellowish color with black streaks occasionally emanating from the center. The surrounding liquid metal will have a brownish dark color; the center is where most of the gold is, the surrounding area is mostly lead;

13) Keep repeating the process of slowly letting a little amount of molten metal out of the crucible while rotating it counter-clockwise. Turn the fire off and on to let lead gas out;

14) Eventually, you are left with the center. At this stage, turn off the air and kerosene supply.

15) Let the molten metal cool and solidify. At this stage, you may have around 200 to 300 grams of solid metal (“nugget”), depending on when you stopped the thinning process



STEP TWO

1) using a smaller crucible, say 10 cm x 15 cm, heat it up, add a handful of borax;

2) at this stage, you will need SILVER three times the weight of the “nugget”; add the gold plated lids as well, melt together in the crucible;

3) max heat till thoroughly mixed;

4) prepare a small drum, filled with water, just below the edge. Let another guy stir the water with a paddle in a round like motion;

5) pour the molten metal (nugget and silver) into the drum of H2O; the super heated crucible is picked up with metal tongs;

6) the result is “popcorn” metal, containing, gold, silver and other metal remnants;



STEP THREE

1) Using a stainless steel bowl, put the “popcorn” metal over a gas stove. Using a plastic cup with handle, pour nitric acid into the bowl with the popcorn. The reaction will be instantaneous,

lots of toxic smoke. The process will have to be repeated several times. The intention is to remove the silver and other metals eventually leaving the gold which appears as brownish mud or ovaltine like

material. Mike, I am not going into details here now as I am sure the other guys know what follows.



I’ll talk to you soon,



Best regards,

Roly

 

[goldsilverpro]

This was a long drawn out post, that said nothing, that I decided to summarize.

All in all, this seems to be a shallow crucible about 12" X 16". When 10kg of lead and 3kg of parts are put into it, they would only be about 1" deep

 

[lazersteve]

This process can best be likened to large scale cupellation. The lead is being oxidized to litharge which gathers the base metals in the borax. The molten lead gathers the gold and the air re-oxidizes the lead back to litharge which in turn oxidizes more base metals to be removed by the borax.

The resulting 'nugget' is bound to contain considerable amounts of impurities. This explains the need to cornflake and inquart the resulting nugget with silver.

My only question is why doesn't the lead stay alloyed with the gold? In cupellation the lead oxide* is absorbed by the cupel. Does the clay crucible absorb the lead oxide *?

It would seem a lot cheaper/easier just to dissolve the copper with your nitirc or AP and skip the cornflaking and inquartion. Especially when you consider the toxicity of lead and it's vapors. Then process the resulting gold powder/foils as usual. You'll also save the cost of the lead, the kerosene, the power for the compressor, borax, silver, and the environment.

Steve

*Corrected lead to lead oxide Thx GSP.

 

[goldsilverpro]

Steve,

In cupellation, the lead doesn't go into the cupel. The furnace door is cracked open a bit to allow a little air in. The air oxidizes the surface of the lead. The lead is rounded up in a convex meniscus. The lead oxide (litharge) formed slides down off the meniscus and is absorbed by the cupel. Any base metals are oxidized and also absorbed. The cupel absorbs oxides but not metals.

The borax is removed in step 9

Lead oxide is yellow. He says the center turns yellow following the air.

 

[lazersteve]

So where does the lead go here? Up in smoke and into the flux?

Steve

 

[goldsilverpro]

Are you thinking the crucible is a big cupel? Interesting. Cupels can be made mainly with Portland Cement, which is pretty strong.

Silver used to be removed from lead in a big 5' diameter cupel furnace. Except, the lead oxide was removed from the surface by skimming, I believe.

 

[lazersteve]

Not the same container material just a similar process on a larger scale.

I still don't understand why the gold doesn't alloy with the lead.

Steve

 

[Harold_V]

That's as close as this entire concept has come to making any sense. It's a far cry from the original statement of gold accumulating in the center of lead, which is poured off, leaving the gold behind.

Assuming that's what's happening, didn't I make mention that lead is usually removed via cupellation when it's used as a collector? I get the idea that the person relaying the information isn't privy to what's really going on.

Harold

 

[goldsilverpro]

The gold has to alloy with the lead, unless something like zinc is added. That would be the simplest way to get it out of the lead. If I were to do this idiocy, that's the way I would do it. The zinc doesn't alloy with the lead, at all, and silver has a 3000 times more affinity in zinc than in lead. The Wiki article says gold works the same way.

I still think zinc could be the hidden ingredient.

 

[Platdigger]

Hey guys,
I may have an idea why this works. With the exception of the first lead that is poured off, this could be the deal.

When they shut off the kerosine for 3 minutes at a time, obviously lead is oxidized. Especialy since the air is left on. Much of the lead oxide going up in smoke.

Now, when the fire is relit, if this is a reducing flame, oxidized lead is rereduced.

Now, without stirring this newly reduced lead shouldn't have much gold in it besause when it was oxidized the gold stayed with, (if you will) the formerly reduced molten lead. Or, the lead that was not oxidized.

OK, this newly reduced lead should be on the outside, at least at first.

Now, if this newly reduced lead was being carefully poured
off.............yea?........

......therefore more and more gold is concentrated to the center as this process is continued.
Think?
Randy

 

[Platdigger]

In other words, it is the inertness of the gold, not being oxidized with the lead when the kerosene is shut off......that makes this process work.
Randy

 

[goldsilverpro]

Maybe, Randy.

Most of the primitive refining processes that I've seen are based on old mining methods.

I just read about an old method of separating silver from lead called the Pattinson Process. It was the state of the art in the mining industry from 1833 to 1850, when it was supplanted by the Parkes Process (the zinc process that I've talked about). This was based on the fact that pure lead had a higher melting point than a lead/silver alloy. The lead/silver was vigorously stirred as the temperature was reduced. A little below the lead melting point, fairly pure lead, containing little silver, crystallized out. The liquid phase contained most of the silver.

According to T.K. Rose and, in looking at the phase diagram, it also worked for gold.

Are the pins on these processors made of copper? The lead-copper phase diagram sure looks a lot different. With any amount of copper in the lead-copper alloy, the melting point is higher than pure lead.

Unfortunately, I couldn't find a ternary phase diagram of a lead-gold-copper melt system. This might be the answer.

If the pins are Kovar (Fe, Co, Ni), that would really make it complicated

It could be a combo of cupellation (from Steve), Randy's idea, the phase diagrams, or whatever. Who knows. My brain hurts.

Since no once else has posted on this for awhile, I assume we give up. So, Roly, it's time for you to give us the complete technical details of why and how it works.

Another thought.

We all agree that, when the air is blown on the surface, lead oxide is produced. Lead oxide has a melting point of 1630 F and it's color is yellow. If anyone can figure out why the gold would be combined with the lead oxide, that may be the answer. Maybe, with all that copper (or Fe, Co, Ni) in the lead (possibly the brown color), at the high temperature, the gold is forced out of the lead and combines with the molten lead oxide (Randy). My brain hurts even worse.

 

[Platdigger]

Molten lead oxide? I thought lead had to be reduced to be molten. As with any metal.
Randy

 

[goldsilverpro]

Lead oxide, as a chemical, will melt at 1630 F. It doesn't have to be reduced to lead metal first.

 

[Rhodium]

:mrgreen:

 

[qst42know]

This method is more or less a scorification process. It is described by Fulton beginning on page 123. It is also very simillar to the Perkins Excess litharge assay method. described on page 116.

http://books.google.com/books?id=AJANAAAAYAAJ&pg=PA193&lpg=PA193&dq=fulton+fire+assay&source=bl&ots=c4KBsC_rH4&sig=mN2C4OqAc4HnZHJ_zgkHX7S6AYc&hl=en&ei=7F7NSqP-Bomm8Aap0-juAw&sa=X&oi=book_result&ct=result&resnum=1#v=onepage&q=assay%20of%20impure%20ore&f=false


I have used this primitive technique several times (before I knew better) on these chips. The surplus lead oxide can be poured off, it is very fluid while hot but glass like when cooled. Ceramic pieces do want to float but will often get stuck to the bottom and sides. As a primary collector of gold it does work though not very efficiently. Most of these tiny buttons started from a scorification.

As far as the chemistry involved I can't explain it, but in another chapter in the same book they describe the formation of borates of various oxides formed being important to the process.

 

[T3sl4]

FYI, if you have just lead and gold, the eutectic will be moderately rich with Au, while the Pb crystallizes out at a fairly high temperature (my graph shows the eutectic at 488K, while lead melts at 600K). If the lead is cooled slowly, possibly directionally, then solid, fairly pure lead (99.9%?) can be seperated from the rest. Especially if zone refining is employed (remelting a zone from end to end, repeatedly, in the same direction).

What little eutectic is present would indeed solidify in the center (if just cooling in a crucible).

This method is plausible if the lead is reused, so that the concentration of gold in solution remains fairly constant as gold-bearing lead is removed and more gold added.

Tim

 

[qst42know]

This should only be seen as a very crude means of collecting the gold values together. The beads shown were cupeled to remove the great excess of metallic lead. Before cupeling it only looked like a ball of lead covered in slag. None recovered from scorifying alone ever resembled gold at all. At no point in the process did it ever appear to be separate metals.

Refining? not really. A very coarse recovery? yes.

A eutectic may theoretically exist on a chart, but if you could reach that point control and sustain it for a period of time what would you do then? Motion alone can change a crystallization point.