my next learning challenge

Hi everyone!
I was thinking of recovering the gold from my ceramic cpu box for the next learning experience. The picture is the family sitting around the porch with my cpu collection.I think the other twin cut off some of the collection at the bottom so he could get his brother in the picture.
Im in the process of breaking up the ceramics, most of the gold plated heat spreaders break up along with the ceramic, so did alot of the small chip in the center.
As I was studying I ran across gold n scrap's video where he dissolves everything in AR and then drops the gold from the dirty solution. I was wondering if I would be better off to heat the material in a dilute nitric bath first to remove as much of the base metals as posible and then run the AR. Or I could run an AP bath before going to the AR.
I still have to do some searching about the presents of tin. Most of the solder or brazing apears to be gold. Afew have a silver colored braze. I'm going to see if AP solution I dropped on some of the silver braze reacts when I get home. A question! If there is a reaction, and I put a small piece of the material with the silver solder in HCl,if there is tin in the solder It should turn purple if I add a drop of my auric chloride solution? Thanks for any advice or links that would be helpfull!
Will weigh it up after I finish breaking them. It's about ten pounds. I post my progress!
excited! artart47

If the heat sink breaks, you do not want to do them directly in A/R. That is a sintered tungsten/ copper heatsink, and needs a good hot bath in 50/50 nitric/water. (example pentium pro) If the heat sink bends, it is a gold plated kovar lid. (example 386/486/pentium) Some do this in VERY hot nitric, or in hot A/R. either works, but be warned, both methods can react very very vigorously and you need a beaker at least 5 x the volume of liquid to prevent foam-over loss. Both methods fume prodigiously.

Hey! Thanks Glondor!
That info could be is a lifesaver. I'll pick out as much of the heatsink material as I can to do seperate or do it in smaller batches in large beakers.
artart47

Hey art,

I don't know if you have read through this post http://goldrefiningforum.com/phpBB3/viewtopic.php?f=52&t=12845 but it has a wealth of information on ceramics.

cnbarr!
Thanks for the link. I've run accross it before but I'm glad you brought it to my attention again. per-haps it has all I'll need.
artart47

Check out that evil grin.

ive seen some of your work. im sure you will do good no matter how you go about it.

Hi all!
palladium;
yah! I can't help but wonder what was going through his little head right there? I hope it wasen't" after dad goes to sleep one of these nights, I'm gonna get his gold"
Geo;
Thanks! that truly means alot comming from you!

I've been pondering the idea of like a small, sealed AR stockpot. after my ceramic cpu pieces are processed I could pulverize them and leave the powder in there and forget about it, same with the fiber cpu bodies. I already dump alot of stuff in a plastic barrel that receives my spent AP solutions. That idea will be contingent upon what I find out about the shelf life of dilute AR if it's sealed.

glondor said:

If the heat sink breaks, you do not want to do them directly in A/R. That is a sintered tungsten/ copper heatsink

Click to expand...

Actually, the opposite is true.
W bearly reacts with AR, the only difference is that it will later precipitate (when cold) a small amount of yellow WO3 that is easly filtered out.

But anyways, leacing first the silver brazing with nitric is an exellent step both from the silver recovery and the following AR point of view.
Personally, i do not bother to leach out ALL of the base metals, as Kovar reacts very slowly with nitric (even when hot). Leach just enough for the pins and heat spreadrs to detach from the ceramic. wash well with D. water and move on to AR to dissolve Kovar and gold with AR.

As for Gold plated Kovar lids (those that do not break), i just place them in cold dilute nitric and let it soak for a week or two.
The gold plating will fall off the base metal and you could easly pick out the the kovar body with tweezers and process the foils alone.

I only run my lids for 48 hours in cold nitric and the foils simply flake off with swirling and rinsing.

Here's my most recent batch after soaking:




after collecting the foils in a pyrocream dish:



and in a 4 liter beaker before refining:



I've actually been putting together a slideshow of the process for everyone to learn.

Steve

samuel-a said:

glondor said:

If the heat sink breaks, you do not want to do them directly in A/R. That is a sintered tungsten/ copper heatsink

Click to expand...

Actually, the opposite is true.
W bearly reacts with AR, the only difference is that it will later precipitate (when cold) a small amount of yellow WO3 that is easly filtered out.

Click to expand...

Glondor is 100% correct here, putting the tungsten topped cpus directly in AR is a bad decision for several reasons:

1) The yellow powder (oxidized tungsten) requires lots of rinsing to remove the gold solution from it's structure,
2) The yellow powder's slight acid solubility allows it to make it through several stages of filtration,
3) Soaking in nitric acid first allows the tungsten plates easily to be collected in tact without breaking them up,
4) The yellow powder will give false positives to stannous chloride as a cornflower blue color,
5) In effect, if you do not remove the tungsten heat spreaders first, you are putting unnecessary garbage into your AR reaction (GIGO).
6) The yellow powder tends to stick to buckets and beakers leaving 'ring around the beaker' if it is not removed before AR treatment.
7) Unnecessarily making the yellow powder by going straight to AR with gold topped ceramic cpus adds another waste stream (the yellow powder) to your processes.

Steve

lazersteve said:

1) The yellow powder (oxidized tungsten) requires lots of rinsing to remove the gold solution from it's structure,
2) The yellow powder's slight acid solubility allows it to make it through several stages of filtration,
3) Soaking in nitric acid first allows the tungsten plates easily to be collected in tact without breaking them up,
4) The yellow powder will give false positives to stannous chloride as a cornflower blue color,
5) In effect, if you do not remove the tungsten heat spreaders first, you are putting unnecessary garbage into your AR reaction (GIGO).
6) The yellow powder tends to stick to buckets and beakers leaving 'ring around the beaker' if it is not removed before AR treatment.
7) Unnecessarily making the yellow powder by going straight to AR with gold topped ceramic cpus adds another waste stream (the yellow powder) to your processes.

Click to expand...

For me, All of the above is negligible.
Either way could achieve same degree of success after having some experience. And you know that.
Anyho, the purpose of my post was fulfilled, now he knows about another alternative rather than just one 'correct' way.

I guess it all depends on how many gold topped cpus (ones with tungsten heat spreaders) are in your scrap. For me I run 20+ pound batches of solely tungsten topped cpus at a time so separating is a must.

Here's a partial list of 'gold topped' cpus that have the tungsten tops:

Cyrix/IBM/Via 6x86



Pentium 66/60/90



Pentium Pro



Orion



DEC/Alpha



and numerous other miscellaneous ceramic cpus across the ages of electronic history. The above mentioned ones are the most common.

As a rule of thumb:

If the top side of the cpu is plated with gold that is not a kovar lid, it has an integrated tungsten alloy heat spreader.

I separate each common type and run them separately as each has it own unique preparations and cleaning requirements before processing to achieve the best results. One or two of these cpus in the mix is no big deal, but when you have more than a pound of them, they should be run separately.

Steve

Easiest way to sort kovar from tungsten, use a magnet.

Göran

Hi everybody!
I just want to thank you for your advise. After much thought, and because I'm more interested in experiencing working with some of the things that can be involved like tungsten in your mix, than I am in just doing it efficiently, I decided to try it the way Sam posted. Sam used the phrase, "results with experiece" It was interesting and I have a new appreciation for tungsten!
I broke up a few grams short of eight pounds of ceramic cpu's rather than treat with nitric, I went right to AR. Heatsinks and all. covered with 32% HCl and 10ml. additions of 67%nitric. when reaction began I slowly added heat.
note. NEVER do this indoors! Do any work with nitric acid outside when there is a steady breeze that blows fumes awayfrom you. Or, if you are indoors you MUST have an exhaust hood that will protect you from the fumes. See our safety section. Nitric fumes will kill you!
After about an hour at a simmer addition of a couple ml nitric evolked no reaction, it was allowed to cool, decanted and rinsed with water, The solids were placed in the red tub for further leaching all of the base metals were not totally disolved. there are still parts of the tungsten heat spreaders. They have a pale green film and the pieces of the shattered glass centers of the cpu's still seam to be bright gold. I'll be doing a second leach after a further crushing of the peices and I expect there is additional gold remaining with the base metals.
I started by filtering and expected to but heads with the yellow Tungsten oxide you spoke of and was alittle disappointed. There was alittle of the yellow but alot of grey/white powder. (all of what was filtered out is in the large glass jar)
The AR was now a very dark greenish brown solution. I added ten grams of SMB and over the next day you could see alot of gold powder at the bottom of the filthy solution and metallic gold crystals on the surface. Spreyed them down and then decanted thru like eight coffee filters into a pail.
The gold powder and crysals went to a Harold wash cycle, were refined AR again,dried and is the powder in the photo! Au. 10grams from the first leach! cool!
Next I Put a copper piece into the pail to be sure any remaining micro gold particals that passed filtration any trace of free nitric or dissolved gold would drop.
The solution was then run thru the same stack of filters multiple times untill the filters were packed and a sample of the dirty AR appeared to be unclowded.(filter was beautiful! brown black and the violet color on the edges)
The filter papers were placed in a beaker, covered with HCl and chlorox was added. The resulting gold chloride solution was dropped with SMB (that is the jar in the background of the photo ,SMB was just added when the pic was taken.will post the amount of gold that came from the filter.
This has been a true learning experience. First! It would be a lot easier to follow Lasersteve's advise and remove the heatspreaders first.
I will post more as I continue working on this experiment.
And thanks again for all your advise. artart47

Hi everybody!
Here is the button that came from the first leach. It is almost ten grams. the scale flips between 9 and 10.
I'm still cleaning the powder that came form processing the coffee filters.

Art,
I like reading about your success in your learning challenges, and it puts a smile on my face to see that gold on your scale.

lazersteve said:

I've actually been putting together a slideshow of the process for everyone to learn.

Click to expand...

As promised, I have posted a new slideshow "Processing Ceramic CPU Lids" to my you-tube channel (lazersteve) and my web site (Gold Videos Section) that shows an overview of how I do my ceramic CPU lids.

The slideshow also has instructions on how to enter my Gold Filled Scrap Giveaway.

Drawing for the half pound (227g) of Gold Filled Scrap with an estimated $250 value will be held on September 1st, 2013; and the winner will be posted on my website. I will cover all priority mail shipping charges to the winner, anywhere in the world that I normally ship to.

Depending on the level of participation, I may up the drawing prize to a full pound of Gold Filled Scrap.

If everyone likes this idea, I will start giving away scrap each month and posting a new short slideshow with drawing and contest instructions on a monthly basis.

Keep an eye on my website and this thread for updates and details on the drawing.

Good Luck everyone!

Steve

Update to Half Pound of Gold Filled Scrap Giveaway Drawing:

The gold filled drawing has been active for 10 days now and there are a total of 7 unique names in the hat to win the half pound of gold filled scrap.

Good Luck to those of you who have entered and thank you for participating!

Steve

maybe its my browser or i just looked over it, but i couldnt find a slideshow.