How do I extract gold from all of this?

[JiminyCricket]

I have a lot of gold scrap from old Motorola electronics from the 70s thru the 90s. How do I extract the gold? Or should I just sell it as gold scrap? And who buys this sort of stuff? Also I have drawers and drawers full of vintage capacitors and someone said they contained palladium? Should I extract that too or is it not worth the hassle?

 

[orvi]

From pins I see, quite easily with AR. Capacitors for PGM are bit more difficult.
If you enclose detailed pictures of material, i think some members could be interested. Main route for sell/buy gold scrap is eBay.

 

[vgecas]

At first remove as much non plated material as you can, like cut off non plated transistor caps. Remove pins from plastic. Then cover everything with sulfuric acid (battery acid will do), heat a little bit and start adding nitric acid in small increments as needed until all base metal will be dissolved. At this point you should have relatively clean gold foils left. Process them in AR.

P.S. i have just noticed, that you are a fresh user. please be shure that you know what you do. If you have doubts - take a break, read posts here and only then process, the gold won't run away.

 

[JiminyCricket]

At first remove as much non plated material as you can, like cut off non plated transistor caps. Remove pins from plastic. Then cover everything with sulfuric acid (battery acid will do), heat a little bit and start adding nitric acid in small increments as needed until all base metal will be dissolved. At this point you should have relatively clean gold foils left. Process them in AR.

P.S. i have just noticed, that you are a fresh user. please be shure that you know what you do. If you have doubts - take a break, read posts here and only then process, the gold won't run away.

I dropped a few 1950s military pins into nitric acid that my buddy had to see what it did and it bubbled out the middles of them and left these gold shells. Now what do I do with them? I have like 3000 of these military pins. They came out of a 1950s military phone operator switchboard.

 

[Martijn]

Welcome to the forum.
If this is all you have, i wouldn't bother with going after acids, materials and safety gear for that little bit of gold. Sell it on ebay and check first what people charge for scrap.

If you want to dive into the fascinating world of recovering and refining to learn and expand your knowledge in general, this can be a very rewarding hobby, and with the acquired skills you could start refining scrap jewelry or high end e-waste as an income.

But know this comes with it's dangers.
Metals in solution are toxic. The fumes created are toxic. The chemical waste needs to be kept at a minimum and processed to dispose of safely.

Each typ of component needs a different approach or process.
Before you start anything, study the forum, learn to use the search function and ask here before actually perfoming chemistry.

I would suggest the copper chloride leach to start with, aka AP. Acid Peroxide.

AR, Aqua Regia is a refining process. Not used often to separate base metals from precious metals. Which is recovery, not refining.
For the thicker parts, i would suggest a sulphuric stripping cell.
Be safe.

Martijn.

 

[Martijn]

Can't wait to get that gold right?
Slow down! Take your time.
Gold feaver can be lethal.
Sure, nitric will get the base metals, but will leave you with waste. And is considered too expensive for plated items. Great to test a few pins and leave the gold behind to get an idea of whats there.

So you could use that bit of of gold to test with. Dissolve one in a bit of HCL and bleech.
Save some gold chloride as a reference for your stannous chloride test solution.

But slow down. Take your time to learn.
Take notes, weigh and measure what you have before and after a process, how much you add, how long it takes to dissolve things.
Learn about tin in solder and why we avoid it.
Some catchy but very true refiners one liners:
Trash in, trash out.
And when in doubt, cement it out.

Start your study with dealing with waste:
https://goldrefiningforum.com/phpBB3/viewtopic.php?f=85&t=10539
Have fun!

(Edited for spelling)

 

[cejohnsonsr1]

First step is to separate the gold from everything else. Best and least expensive method is AP. Only drawback is that it takes quite a while for the AP to do its work and it’s a bit more labor intensive getting the gold foils separated from the base metals. The other option is to use distilled water and Nitric acid to dissolve everything except the gold. This process is a lot faster but way more expensive and you need to take serious precautions during the process to avoid poisoning yourself or others. And there’s the matter of waste treatment and disposal. All things considered, if you’re asking the question, you’re not really prepared to be working with Nitric yet. Use the AP method and study the processes until you really understand how and why they work. Hoke’s book is an excellent reference. Sreetips on YouTube has detailed videos on just about every process imaginable. The main thing you should take away from this is that you have to separate the gold from everything else before you can proceed. DONT JUST DUMP IT ALL IN AR. That won’t work. Another thing to be aware of is that this kind of material has far less gold than it looks like. Sreetips has a recent video on this kind of material that will demonstrate both the process and the yield. I highly recommend watching that before you do anything.

 

[JiminyCricket]

First step is to separate the gold from everything else. Best and least expensive method is AP. Only drawback is that it takes quite a while for the AP to do its work and it’s a bit more labor intensive getting the gold foils separated from the base metals. The other option is to use distilled water and Nitric acid to dissolve everything except the gold. This process is a lot faster but way more expensive and you need to take serious precautions during the process to avoid poisoning yourself or others. And there’s the matter of waste treatment and disposal. All things considered, if you’re asking the question, you’re not really prepared to be working with Nitric yet. Use the AP method and study the processes until you really understand how and why they work. Hoke’s book is an excellent reference. Sreetips on YouTube has detailed videos on just about every process imaginable. The main thing you should take away from this is that you have to separate the gold from everything else before you can proceed. DONT JUST DUMP IT ALL IN AR. That won’t work. Another thing to be aware of is that this kind of material has far less gold than it looks like. Sreetips has a recent video on this kind of material that will demonstrate both the process and the yield. I highly recommend watching that before you do anything.

I have a friend who has 4 liters of nitric acid and thats why I'm finally trying to extract all the gold from the gold scrap I've collected. I have like 4 lbs of these old military pins and they seem to be gold filled, not gold plated.
Which is this stuff:


And this is why I'm finally trying to extract the gold now that I found someone with Nitric acid since these seem to be thick enough to retain their shape after putting them in nitric acid. The only downside I noticed is that I have to cut each one in half so that the nitric can eat out the junk inside of them.

But I also have a lot of gold plated computer scrap as well.
Like this stuff:


I also have 2 rooms full of 70s and 80s Motorola electronics with lots of gold pins that I haven't even touched yet and some vintage gold filled watches.

I just don't know what to do with the gold scrap after I put it in nitric acid. Do I melt it? Clean it? Leave it like it is? Send it to a professional?

 

[Martijn]

You dissolve it in Aqua Regia and precipitate the gold to further wash it before you melt it.
In short.

 

[nickvc]

You may well use less acids if you dissolve the pins in AR , it will preferentially dissolve the copper first and if you do the dissolution slowly and carefully you could remove most of the copper leaving the gold. Testing using stannous should confirm if you did dissolve any gold.

 

[Noggin]

To do this recovery you need:
1. Fume hood that vents to the outside, or a place to work outside in open air (but you still need fans to push fumes away from you).
2. PPE - gloves that don't catch fire when exposed to the specific acids you're using, eye protection, respirator, maybe something for your clothes.
3. Hot plate
4. Assorted beakers, stir rods, watch glass, and other things depending on the methods you choose
5. Waste treatment buckets, scrap copper, and the willingness to spend time treating your acidic, toxic waste once you've done the fun stuff
6. Nitric, hydrochloric, and sulfuric acids, and a place to safely store them
7. Oxyacetylene torch and/or lab furnace for melting metal when necessary (alloying and creating bars of the final product)

You will need to be familiar with at least three methods for your particular scrap. Sulfuric cell electric deplating and it's underlying chemistry, recovery of gold by removal of low-value metals, and refining of gold via converting to chloroauric acid (there are multiple ways to do this, including aqua regia).
I would learn deplating first, which will get a lot of those pins out of your way. Start small then when comfortable, scale up. Like you can do 20 pins, and note the result. You'll see the pins are devoid of gold, you see the slimes created. Then do more, and after a few times of running small batches you'll get a feel for when it becomes less efficient to scale further. Process all your pins with the methodology you learned.
When done with the deplating you can look at refining all that gold at once. There's no need to do that right away, but when you do, you'll also do a little at a time, and scale up.
If you don't need a hobby like this, you'll realize it before too long and you won't have screwed up your whole collection that someone else might pay good money for. I used to work for Motorola - hopefully you're not tossing anything too collectible!!

 

[orvi]

This (dissolving mostly BM in AR) is sometimes tricky to perform, but it could be done very well if good material is treated. Also you could in theory not dissolve all metals in the pot and some dissolved gold will reprecipitate on their remains. Decant the solution after few days of cementation, test it with stannous... And the remains transfer to small beaker and dissolve with fresh AR.

From the time and effort point, with like pound mid/high grade i always go straight to AR (less nitric consumed, quick and less NO2 produced because deeper reduction of HNO3).

 

[orvi]

I have a friend who has 4 liters of nitric acid and thats why I'm finally trying to extract all the gold from the gold scrap I've collected. I have like 4 lbs of these old military pins and they seem to be gold filled, not gold plated.
Which is this stuff:

View attachment 47588
And this is why I'm finally trying to extract the gold now that I found someone with Nitric acid since these seem to be thick enough to retain their shape after putting them in nitric acid. The only downside I noticed is that I have to cut each one in half so that the nitric can eat out the junk inside of them.

But I also have a lot of gold plated computer scrap as well.
Like this stuff:

View attachment 47590
I also have 2 rooms full of 70s and 80s Motorola electronics with lots of gold pins that I haven't even touched yet and some vintage gold filled watches.

I just don't know what to do with the gold scrap after I put it in nitric acid. Do I melt it? Clean it? Leave it like it is? Send it to a professional?

Take time. This hobby will pay some bills, but it need some experience to produce good results. Gold will not run away or deteriorate while you find the most suitable method for extracting it.

With pins, i personally like to process them with AR. Whole, no pretreatment, just straight dissolve them in AR and then drop the gold with sulfite. But with bigger batches, it start to be tedious as vast ammounts of liquid are produced. Roughly speaking, for every kilo of scrap like 4-5 liters of soup. You need to deal with it afterwards, responsibly.
If you have enough space to accomodate few plastic buckets for waste treatment, then why not. If done properly, with direct AR treatment, 99,9 % gold could be produced in one sequence.

Guys also suggest you to make research about "sulfuric acid stripping cell". Very effective way of de-plating pins and anything gold plated by means of electrochemistry. Electrolyte is concentrated sulfuric acid tho. It have its own minuses, but as far as I know, no toxic fumes are evolved during the process, which is a good thing (AR dissolving is nasty and far from ideal in terms of toxic gasses emitted). And it is also scalable easily, acid could be regenerated and practically NO BASE METAL WASTE is produced, as the de-plated pins remain untouched after treatment, so no gallons of toxic base metal soup are produced. But working with concentrated sulfuric acid need rigorous exclusion of water and quality protective equipment (gloves and protective glasses/shield are a MUST).

You need to decide if you want to jump into this field (very fascinating, colorful, addictive and dangerous if done in improper way...) or just clean the material and sell it.
There is no need to hurry. Very advisable is to learn basic principles (also theory to some extent), to understand every step of the procedure with its chemistry behind. Many mistakes will be prevented by deeper understanding.

And last note, not only pins contain gold. You say you have whole boards from 70-80´s. Do not toss away anything from them when you attempt to depopulate the components, unless you know for sure its worthless gold is also inside many other parts, transistors, diodes, integrated circuits... Palladium in ceramic capacitors (many shapes, plastic/ceramic/epoxy casings...), silver/gold/palladium in relays. Old optoelectronics like LEDs have thick gold bonding wires often. Also tantalum capacitors could be sold for decent money... And some of them are made from silver... Even some old resistors contain precious metals. Precise potentiometers and trimmers from quality electronics have very thick gold or palladium plated parts inside. And many many more things to consider

Just be safe and think twice about everything in terms of recovery of PMs. If you decide to process your material on your own, think about a method that is well suited for you, and discuss it with somebody experienced. Also before this, search it here on forum, just type the key-words to the search bar and learn. All of this stuff is well documented and done before numerous times.

 

[cejohnsonsr1]

I have a friend who has 4 liters of nitric acid and thats why I'm finally trying to extract all the gold from the gold scrap I've collected. I have like 4 lbs of these old military pins and they seem to be gold filled, not gold plated.
Which is this stuff:

View attachment 47588
And this is why I'm finally trying to extract the gold now that I found someone with Nitric acid since these seem to be thick enough to retain their shape after putting them in nitric acid. The only downside I noticed is that I have to cut each one in half so that the nitric can eat out the junk inside of them.

But I also have a lot of gold plated computer scrap as well.
Like this stuff:

View attachment 47590
I also have 2 rooms full of 70s and 80s Motorola electronics with lots of gold pins that I haven't even touched yet and some vintage gold filled watches.

I just don't know what to do with the gold scrap after I put it in nitric acid. Do I melt it? Clean it? Leave it like it is? Send it to a professional?

This link is to a VERY condensed version of a much longer, more detailed video that explains the process most appropriate for what you’re trying to do. Watch this video and please note the yield, keeping in mind that he’s way beyond just very good at this. Then if you still want to proceed, watch the longer version and really study before you begin. Merry Christmas.

 

[JiminyCricket]

To do this recovery you need:
1. Fume hood that vents to the outside, or a place to work outside in open air (but you still need fans to push fumes away from you).
2. PPE - gloves that don't catch fire when exposed to the specific acids you're using, eye protection, respirator, maybe something for your clothes.
3. Hot plate
4. Assorted beakers, stir rods, watch glass, and other things depending on the methods you choose
5. Waste treatment buckets, scrap copper, and the willingness to spend time treating your acidic, toxic waste once you've done the fun stuff
6. Nitric, hydrochloric, and sulfuric acids, and a place to safely store them
7. Oxyacetylene torch and/or lab furnace for melting metal when necessary (alloying and creating bars of the final product)

You will need to be familiar with at least three methods for your particular scrap. Sulfuric cell electric deplating and it's underlying chemistry, recovery of gold by removal of low-value metals, and refining of gold via converting to chloroauric acid (there are multiple ways to do this, including aqua regia).
I would learn deplating first, which will get a lot of those pins out of your way. Start small then when comfortable, scale up. Like you can do 20 pins, and note the result. You'll see the pins are devoid of gold, you see the slimes created. Then do more, and after a few times of running small batches you'll get a feel for when it becomes less efficient to scale further. Process all your pins with the methodology you learned.
When done with the deplating you can look at refining all that gold at once. There's no need to do that right away, but when you do, you'll also do a little at a time, and scale up.
If you don't need a hobby like this, you'll realize it before too long and you won't have screwed up your whole collection that someone else might pay good money for. I used to work for Motorola - hopefully you're not tossing anything too collectible!!

I have a pageboy and a pageboy 2 by Motorola. Aren't those like the original pagers? I also have some kind of Motorola tester for vacuum tubes I think and a bunch of Motorola police scanners and wires and intercom systems and little desk speakers and lots of little Motorola circuit boards and big Motorola walkie talkies and their charger stations and corded microphone attachment thingies and etc. I don't know if any of it is collectible though.

 

[Noggin]

I have a pageboy and a pageboy 2 by Motorola. Aren't those like the original pagers? I also have some kind of Motorola tester for vacuum tubes I think and a bunch of Motorola police scanners and wires and intercom systems and little desk speakers and lots of little Motorola circuit boards and big Motorola walkie talkies and their charger stations and corded microphone attachment thingies and etc. I don't know if any of it is collectible though.

Check eBay, you might be surprised especially about the tube tester. Individual circuit cards, pins, etc can be your initial targets for scrapping. Omegageek just made a YouTube video talking about the values of some individual IC chips for reuse, collections, and scrap.
If your objective is to learn gold recovery, this doesn’t really matter. But if you want to maximize income, scrapping is usually the last resort.