advice?

[Harvester3]

Hey you all,
Well, I bathed an older LSI processor (the kind with the lugs on top) in a weak nitric solution. It reacted immediately with the gold, making salt in the process. The result is shown in this photo.
So, that's what I wanted, right?
Now, I tried again, but apparently my nitric solution was too strong, or too much heat, as it went brown/black, and appears to have eaten the base metals... Now what? I'll try to post photos of each.
Any help is appreciated. It took a lot for me to just attempt this. I'd be better off just selling scrap (if prices weren't in the tank!)
Thanks again.
Jim

 

[qst42know]

The purpose of the nitric is to remove the base metal. However if the gold is finely divided as in low karat (thinly plated) it will be found as sediment in the nitric and is sometimes easy to miss. Or lose in filtering.

 

[Harvester3]

Thanks,
So, my first attempt which yielded the gold shown above was a fluke?
My present project is apparently doing what it should in that case; dissolving all base metals. In that case, the gold will remain at the bottom of the container? I'm sorry, there's a ton of info on this, and it gets confusing for my middle aged brain :?
Thanks again
Jim

 

[qst42know]

Heavy plating will remain as foils but may not be all that was there. Watch for fine sediment in the solution you poured off as this too may be gold. Fine particles my require settling over night. The remaining foils and sediment will need further processing to be pure.

 

[butcher]

and more gold and base metals inside the processors if you did not pulverize them.
remember you still have some salts of nitric on your gold and if adding HCl it would be enough to make a weak aqua regia and dissolve some of your gold, so if you are going to wash them in muratic acid they will need incenerated first, to rid the nitrates.

 

[Harvester3]

OK, slowly please.
First, the first reaction I got, which is shown in the paper filter above, isn't what is supposed to happen with Sulphuric acid and potassium nitrate (didn't have any sodium nitrate) bath, right? It's supposed to dissolve all base metals, which apparently has happened in my second attempt.
So, if all is dissolved in solution, possibly including gold fines, how should I proceed?
The solution is dark brown/blue. I know that doesn't sound good. I'm doing small, single items to determine the value of each, so no big loss, but it sure would be cool if the process was a more simpler one. I know, if it was easy...
Hey, thanks you all. Let me know if I can ever be of service.
Hope all had a Happy Thanksgiving.
Jim

 

[qst42know]

I would rinse with hot water to try to get rid of the crystal salts in the filter.

I would also add water to your original solution, allow it to settle for a while and pour off the top solution saving the solids on the bottom.

Working with such small amounts will add some difficulty. Small losses to filtering and transferring will be magnified.

On small batches I usually work in one container pouring off the base metal solution. And perform a few water rinses in the same container.

The solids and the last of the solution is dissolved together in AR or HCL+bleach, filter or pour only the solution into new container and dropped with SMB. The rinses are HCL, Water, Water, Amonnia, Water, Water.

Then repeat the AR or HCL bleach and SMB drop, and the rinse steps.

 

[butcher]

I use sodium nitrate (not to sure if potassium would effect differently).

now you made a nitric acid solution, which disolves most but not all base metals. if there are no chlorides involved it will not dissolve your gold,but your gold can be very very fine also.

doing single processors to me would be harder than a batch an there is probably more chances of losses.

apparantly you chose nitric to rid your base metals (acid peroxide will work to), so the base metals that nitric can disolve did, but metals and acids make salts of metals.

the salts you see can be salts of acids and metals

so from here I would wash in hot water.let settle decant.

if I was using aqua regia I could dissolve my gold in it without incenerating(rid nitrate) it would disolve my gold and what small amount of metals left from nitric treatment.

but if I wanted to wash in Hcl, to rid the gold of base metals that HCl will attack, that the nitric would not, I would have to incenerate first (cook off nitrates), or if I wanted to dissolve my gold in HCl/bleach, the nitrates need to be removed. (otherwise it would form weak aqua regia and some of my gold would wash away too).

either aqua regia or HCl/ bleach work to disolve the gold.

to me aqua regia is faster but seems to be more problemsto precipitate from , if you do not get rid of the nitric or have too much base metals,

acid bleach alot slower but works very well and seems to me easier to precipitate from, but of coarse the oxides still need eliminated.

 

[Harvester3]

Thanks for the quick response.
So, couple of things;
What's "decant"?
Since my home made nitric acid now carries both base metals and gold, what is the best next step from here? I remember from my gold mill days, it's best to remove as much base material as possible before commencing the concentration process, but it's late for this batch.
Wash in hot water. Does that dissolve the salts?
I have to keep referring to my notes to keep from confusing the different materials such as Aqua Regia, etc.
When I started fooling with this scrap electronics recovery I really thought I could maybe just concentrate with various screens/separators, etc and melt the cons down, hoping the goodies would naturally be on bottom of the lump.
Again, thanks for everyone's patience and guidance. I really used to be a much quicker study.
Possibly too many shots to the head [:~)
Jim

 

[bmgold]

If you haven't done it yet, go to the books section on this forum and download the gold refining forum handbook and also Hoke's book. They are both free and well worth the time to download. Hoke's book is a little hard to understand until you read it and study the processes then it starts to make sense. If you read it enough you will realize just why so many people recomend it.

Also, use the search feature on this site and use the "and" feature to limit the amount of results it brings up.

Check any post by Lazersteve and go to his website. You have to sign in but the username and password are on the first page you come to. His site has lots of videos that show the processes and how to do them. It helps a lot to see something done instead of just reading about it.

Stick with it and do some reading and you will figure it out.

 

[butcher]

ok nitric alone will dissolve the most of base metals making them a liquid, not your gold.as long as no chlorides(like HCl) involved with the nitric.

wash will disolve the salts of base metals.
decant means to pour off liquid but not disturb the solid at bottom, this can be done by pouring carefully, but i prefer to use a suction bulb, or you can also cypher it off. the liquid now contains base metal nitrates, the powder will be mostly gold.
this gold will need futher processing to make it more pure.

if melting gold and base metals even a small amount they only mix in melt,you are right we are eliminating base metals to concentrate, and then trying to eliminate almost every bit of them to make that gold pure as we can.
unless your goal is just to recover it and sell it to a refiner and pay him to do what you can easily do your self with a few more steps.

when doing a single chip it is such a small amount, you probably will have higher loss of gold than a larger batch, just like mining were you can only recover 98% with 2% loss in process, a ton is easier than a hand full and probably less loss due to what may be stuck to jar as extremely fine powder or lost in filters or left in acid or washes etc.
this small of a batch I would not filter it, as your losses would be higher with fine gold sticking to it, I would use suction bulb to remove liquid from powder fairly close to the powder then an eye dropper type tool to get most all of it, giving plenty of time for any fine powders to settle.
what type of refining process do you plan to use?
and hokes book is good advice,
this does kind of seem a little overwhelming but it does get a little easier, but like most other things I dont think anyone will ever learn everything about it,
but if I dont learn something new everyday I might as well be brain dead.

 

[Harvester3]

Ok, what have I done now?
I started a new nitric bath with 2 of the "nubs" which you see on some LSI, etc processors from Silicon Graphics units. Not sure why I did this, but I had a stainless steel strap which I put in the solution for a minute, and noticed material was attracted to it, so left it in overnight.
Now, I removed the strap, and the plated (?) material just slid off the stainless. The solution is green, the nubs are half as large as they were at first.
What happened here, and was it good?
I'm working through Hoage, etc, as well as viewing Steve's fine tutorials several times. Lots of stuff!
Thanks again to you all.
Jim

 

[butcher]

what you have done now is ,you observed the principles of chemistry and electroplating and how a battery works.these same type of principles we use to recover gold.

 

[Harvester3]

Hey Butcher,
Great! ??
But tell me what plated on the SS. Base? Gold? It's still working on a few nubs, and making brown stuff...
Thanks Butcher

 

[butcher]

your solution is green, probably copper, nickel ect and of coarse gold, maybe other metals.
there is what they call electromotive series, activity series, there is an order to them they determine what plates to what and what dissolves in solution to precipitate another metal etcetera. read this and try and find more information on it also look at electroplating and battery theory.
www.chem.vt.edu/RVGS/ACT/notes/activity_series.html

you probably have a combination of several metals plating out of solution as you have also them going into solution dissolving, also some metals will plate out then another one will plate to that powder, not really refining anything thats at least how I see it. You are just removing the metals from your processor and adding them to the stainless steel any metal below chromium on the chart will try to plate to it, probably build up and fall off , some of the acid may dissolve away some of iron out of stainless pitting it enough for some of you values and metalsto stick (bond)to the stainless.
someone else can probably explain this better.

 

[butcher]

Harverster if you are serious about recovering gold try and follow the proceedures, at least till you get an reasonable understanding of what happens, some thing we may do without knowing can make explosives and be pretty dangerous to us and others, expierimenting is great but we need understanding first, the above expieriment is just complicating your process, with metals from the stainless steel, nitric will dissolve some of it, and you are making more posibilitys of loosing values.
How would you like to process your material? read some on it and we will help you.
you will learn these principles and get your gold.

 

[Harvester3]

Thanks Butcher and everyone. The stainless steel thing was really just a fluke which raised curiosity when I saw the plating process take place so quickly.
I am getting the hang of it slowly.
It's hard to stay on it and keep the bills paid at the same time... If gold prices would normalize it seems possible to even make some money on this sort of project.
Again, thanks much you all.
Best,
Jim

 

[butcher]

I cant say theres much money in processing electronic scrap, but it is a great hobby and education, and hopfully well break even

 

[Harvester3]

So, after several viewings of Steve's videos, and reading through the text suggested here, I've got some gold.
Have a look.
The first photo shows some fine powder filtered from the wash. Is this the brown powder that's gold, or ???
Any thoughts are greatly appreciated.
Jim

 

[lazersteve]

Harvester,

I'm not for sure of the order of your photos, but the second one is obviously your gold foils. The first one looks like the residue commonly found when filtering the AP after the foils have been removed. It also resembles the residue found after filtering the dissolved foils from the HCl-Cl solution.

In either case for the first photo of what appears to be gray powder, is likely a by product of the process and not your product. The gold powder should be light tan to coffee brown after adding SMB to the filtered HCl-Cl liquid.

Can you please clarify the order of the photos as well as the exact steps you used to produce the results pictured?

Steve