Gold Recovery Phone circuit boards mistake

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sporty

New member
Joined
Mar 7, 2014
Messages
4
Hello everyone,

I am quite new to urban mining and already did my first big mistake so I am seeking for advice on how to recover Gold from mobile circuit boards. Since I have easy access to cheap, old cells I bougth 100 pieces to start with.
As you can see in the first picture, I have prepared them nicely with removing everything from the circuit board. I then put it in a bin and pored in Muriatic Acid as well as hydrogen Peroxyde with a ratio of 2:1 (see picture 2&3).

The problem I am having now is that it instead of disolving the cooper below the gold plating the gold gets disolved so the plan of having the gold flakes swim on top of the pot is not really working :lol:

Could somebody please advice me on what I am doing wrong and if I can still recover the disolved gold with the solution made with the acid/peroxide mixture?

Any help would be much appreciated.

Thanks
 

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Hi necromancer,

Thank you for your reply. I have already tried to find something in the search but was not really successful. Would you be able to point me in the right direction? I understand that there are different approaches but for a newbie without experience in chemical processes it is quiet difficult to grasp a solid understanding of the different approaches.
 
your not going to find an exact solution or "recipe"
from my research on the topic:

any gold in AP will cement back out, usually AP will not dissolve gold, I'm guessing you used household peroxide 3%?
this process will take a long time (weeks) use of an air stone/bubbler and heat (wouldn't recommend an external heat source with your plastic tubs) will speed things up a bit. don't expect a big recovery, maybe a gram or two for all that, maybe. it helps to remove all the excess metal bits also. I like HCl bath to remove solder then incinerate, then do nitric, then incinerate then AR or HCl/Cl (although incinerating PCB boards would be nasty) your probably going to have to deal with a bunch of green mask pieces that come off the boards also. good luck.
 
you may also want to cut your boards into smaller bits to let the acids dissolve the base metals faster and to get under the solder mask if you are not going to remove it
 
joubjonn said:
your not going to find an exact solution or "recipe"
from my research on the topic:

any gold in AP will cement back out, usually AP will not dissolve gold, I'm guessing you used household peroxide 3%?
this process will take a long time (weeks) use of an air stone/bubbler and heat (wouldn't recommend an external heat source with your plastic tubs) will speed things up a bit. don't expect a big recovery, maybe a gram or two for all that, maybe. it helps to remove all the excess metal bits also. I like HCl bath to remove solder then incinerate, then do nitric, then incinerate then AR or HCl/Cl (although incinerating PCB boards would be nasty) your probably going to have to deal with a bunch of green mask pieces that come off the boards also. good luck.

i see that this is a double post, not sure how that happened. did you by chance double click the "submit button" ?
not sure if you can delete one of the dual posts?
 
2:1 ratio is pretty high on the peroxide, I think. I only use enough to get the process started. Maybe an ounce or so per quart at most. To high of peroxide content can make gold go into solution the way I understand it. The few cell phone boards I have done, a good part of the gold broke down into tiny powder flakes like brown dust in the bottom of the container. The contents of your tub look pretty clear, how long has it been sitting? AP is not a fast acting solution, it may take days or weeks even, for it to work. You really need to read this very much and often, most basic questions are dealt with pretty good there,

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=33&t=796
 
Since you did NOT depopulate your boards first :shock: You are going to be fighting this whole batch to get any gold back

edit to ad;
Hit the wrong button again :roll:
Any gold that dissolved when you added the peroxide is now plated on every piece of base metal in the mix. so now you are going to have to dissolve every bit of base metal to liberate all the gold that plated out. Then rinse each piece to be sure you have recovered all the gold powder that plated on everything, including stuck to the plastic container.

As a hint. NEVER dissolve gold in plastic containers. You will loose gold every time you do it :shock:
 
Thanks for the further hints.

I have left it in the sun for another day and it looks much better now. The gold is slowly coming of so I will just let it sit there for another couple days before I start to filter the gold out.

Nex time, I will depopulate the boards carefully and use a glass bin.

Thanks
 
Welcome...
Do ua all a big favor and stop what you are doing untill you learn what it is you are doing...

The tid bits the others have generously given thus far is only going to complicate matters in that you will be running into more questions and what do I do next. The whole process and why it's done this certain way needs to be learned well in advanced from start to finish before even thinking of touching acid.

Please stop and learn!

B.S.
 
drlakic said:
As a hint. NEVER dissolve gold in plastic containers. You will loose gold every time you do it

Why is that?

drlakic
If you look at plastic under a microscope you will find the surface is not as smooth as you think. Add that porosity to the fact that plastics generate static charges easily, your gold will stick to the plastic quit well. Getting it off usually grinds it in deeper if it doesn't easily release.
The smaller your gold particles are, the harder it will be to get them out of the plastic container.
Have you ever heated some greasy food in a plastic bowl in the microwave :?:
Notice how you can never get the oily grease ring out of the bowl :?:
Your gold will do the same :shock:
 
This is coming from a beginner that uses the HCL/Peroxide method. You have much to study and re-read if you have already read. (I'm not insulting you btw, just a friendly tip is all). First, any board you plan on removing gold from MUST have the solder/lead/tin removed. Remove anything manually you can from the board i.e. capacitors (they have aluminum), flatpacks, chips, etc. Yes it's labor intensive and a pain in butt but if the gold is what youre after then thats what you need to do. I did the same thing when i started btw. What i had was a mash of gold with all kinds of surface mounted components and junk, Thought i was doing it right(didnt read enough) ;) . Upon precipitating my gold, to my dismay, I had black powder and nothing in mass compared to what I put into solution. Oh yeah I was dismayed. Then i learned more by studying. So here's the tips I'll give you that I have learned and if they are wrong I'm sure someone on the forum will call me out. (which is constructive criticism and I don't mind). I'm all about the learning. When you tried to ride a bike did you fall? Probably, but after a few tries you got it. The same applies here.
1) Scratch the greenstuff on the board(solder mask) See if it glints like gold. It comes off easier than copperclad boards do. a jewelers flat blade screw driver is good for that.
2) Remove any or all components you can by hand or use alternative methods presented here in the forum. Save your chips and pins in separate jars to accumulate over time until you decide to learn those processes. Pins, Chips, Processors, fingers, and boards all have different processes to use for the best yields. Make sure you remove any steel/aluminum/tin components or flashing prior.
3) if "said" board contains gold under the solder mask, look up Removing solder mask. (scratching it off is a waste of time) You will find lye is the answer for that.
4) Once all the components have been removed its time to remove the tin/solder/lead. Use straight Hydrochloric acid and immerse your boards. Your gold plate will appear as if it dissolved off or even black. This is a common reaction at this stage. It rubs/washes off. (I freaked out the first time) about a day or so depending on temp.
5) Remove the boards from the HCL and see if the surface mounted chips come off easily by hand or a toothbrush. Let them (components) stay in the hcl for further processing later. (just dont introduce aluminum or steel in the mix).
*6) Now for the beginning stage of recovery.
7) Make sure all boards are clean of ANY surface mounted items. Place your boards in a Very Clean glass container. Add your HCL and just a bit of Hydrogen Peroxide. When I say a bit i mean just a small amount. a couple splashes to get things started. Your solution will turn an emerald green color over time. This is the copper being taken into solution and this is good! Remember that your HCL/H202 solution will take in some of your gold in the beginning of the process but as copper is absorbed it will precipitate it back out in the form of black powder.
8) if your solution turns brown it lacks oxygen in the solution. A few dashes of peroxide will remedy this...or a bubbler.
9) You will start seeing gold being lifted off and floating...thats a good sign. Just keep your solution Green.
10) Once your boards are barren of gold remove them by spraying them down one by one to remove any gold trapped on or in them. Once your solution is free of the boards you can now allow your solution to settle and pour it off into another container (with a funnel and filter to catch anything floating). This was the easy part. The rest You need to study up on if you havent done so already. just don't go walking into this blind. It's more difficult than you think. Also dont forget to learn about stannous chloride to check your solutions for the presence of Gold and other PM's.

If I have missed something in these processes or have erred in some fashion, please point it out to me. I'm far from perfect but learning
 
Yes, there is alot more to it then what's writen so far. Like cuttin the boards down to remove as much non gold baring material as possible.
As well as alot of other things like reusing the solution, then safely dealing with it when done.

Stop doing and please spend the next month or alot more reading and learning what you want to do. So you do not lose anything of value, like your health!

B.S.
... You've fallen, now get up, brush yourself off and learn how to walk before trying to run...
 
If you look at plastic under a microscope you will find the surface is not as smooth as you think. Add that porosity to the fact that plastics generate static charges easily, your gold will stick to the plastic quit well. Getting it off usually grinds it in deeper if it doesn't easily release.

Thanks for the answer. That was also my only assumption for losing gold in a plastic bowl, but I thought that amount of gold lost in it is so small, that it is irrelevant for any calculations. Anyway, dissolving it again from inner walls of plastic bowl and pouring it into glass bowl should solve the problem. :)
 
Plastic is a different beast. Maybe let orange juice go rancid in a plastic container as an experiment to find out how porous the lining is... There is really no known method for 'getting' the smell out, now convert those odor causing oils to gold salts... once 'in' they're there to stay, it isn't rinse away...
 
niteliteone said:
drlakic said:
As a hint. NEVER dissolve gold in plastic containers. You will loose gold every time you do it

Why is that?

drlakic
If you look at plastic under a microscope you will find the surface is not as smooth as you think. Add that porosity to the fact that plastics generate static charges easily, your gold will stick to the plastic quit well. Getting it off usually grinds it in deeper if it doesn't easily release.
The smaller your gold particles are, the harder it will be to get them out of the plastic container.
Have you ever heated some greasy food in a plastic bowl in the microwave :?:
Notice how you can never get the oily grease ring out of the bowl :?:
Your gold will do the same :shock:

Very well put, and great advise !!!
 
Not only did you NOT depopulate the boards, you didn't remove the solder. All that solder will do is cause troubles down the road. Sit back and start reading to learn from others mistakes. We do not take people by the hand and lead them through these processes any longer. That has been done so many times that the old timers here will not waste their time repeating the same old diatribe ad nauseum. You also didn't tell us what the results of your stannous chloride tests were. Surely you did use stannous chloride.
 

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