How to Extract Gold From Electronics

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Introduction: How to Extract Gold From Electronics

About: Hi. I'm Jacob, a high school student interested in science and math. I like to build many different sorts of contraptions and perform experiments on topics that interest me. I hope my project tutorials he...

In this Instructable, I will show you how to extract gold from computers using products most people have lying around in their homes.

The way I extract the gold is relatively straight-forward and pretty easy, but the chemicals used are very dangerous and should not be performed without proper knowledge and equipment.

This process is not supposed to be lucrative. It is a great science project. So don't try to make money off of this process. You will end up losing money!!

Also, please remember if you like this Instructable, please vote for me. I work very hard and spend a lot of time to make these Instructables. It would truly mean a lot. Thanks and Enjoy!

Step 1: WARNING: Hazardous Chemicals Used

Although this method of gold extraction calls for household chemicals, that doesn't mean they are safe. Please be advised that you must handle these chemicals with care. Goggles, gloves, glass apparatus and a very well ventilated room with a fume hood (and a gas mask/respirator are needed as well) or an outside area is highly recommended.

After this experiment is over, I will show you how to properly dispose of the chemicals. You should know before starting this experiment, you must set up an appointment with a hazardous waste processing facility or H-MRF.

DO NOT POUR DOWN SINK OR TOILET. YOU MUST FOLLOW THE STEPS ABOVE, OR RISK BREAKING LAWS WITH HARSH FINES AND EVEN JAIL TIME IF YOU ARE CAUGHT.

PLEASE BE CAREFUL.

If you have any question regarding the safety of this experiment, please ask me through comments or a PM before performing any of this experiment.

Step 2: Acquire Apparatus, Chemicals, Materials and Safety Equipment

Safety first:

1) Goggles

2) Rubber Gloves

3) Gas Mask/Respirator (not needed if performing outside)

4) A Well Ventilated Area (outside or in a room with a fume hood)

Now for the apparatus:

1) One Glass Beaker (thick plastic cups should suffice, but glass is better). Styrofoam and paper will not work.

2) Coffee Filter

3) Scissors

4) Two Plastic Cups

5) A Large Soda Bottle (for the proper disposal of the chemicals after experiment)

And last but not least, the chemicals:

1) Toilet Bowl Cleaner (must contain hydrochloric acid). If you have lab grade hydrochloric acid, by all means use it. Can be found at Home Depot, most home improvement stores and plumbing supply stores. HAZARDOUS; do not ingest or get in eyes and mucous membranes.

2) Hydrogen Peroxide. Can be found at CVS pharmacy as it is used as an antiseptic. HAZARDOUS; do not ingest or get in eyes and mucous membranes.

3) Water will be used at the end of the extraction process.

Step 3: Prepare Electronics for Gold Extraction

In this step, you will need to take your electronics device and pull out any PCBs from it. On the PCBs, look for gold color.

When you find gold, strip all components off the PCB.

If necessary, break the PCB in order to fit it into beaker.

Step 4: Clean Off PCBs

In this step, you should rinse off your PCBs under water and dry thoroughly.

Step 5: Create Your Etching Solution

In this step, you take the hydrogen peroxide and toilet bowl cleaner and mix equal parts of each with enough total solution to be able to fully submerge PCBs. After the solution has been made, drop the PCBs in and make sure they are fully submerged.

This solution is called an etching solution because the solution made above dissolves the nickel under the gold. as a result, the gold foils are detached from the nickel because it has been dissolved.

If keeping outside, I recommend putting a large cup with holes in it so the fumes can escape and contaminates don't enter the solution.

WARNING: This is the most hazardous part as tiny amounts of chlorine gas are released (depending on he concentrations of the chemicals used. I am using 3% hydrogen peroxide and the toilet bowl cleaner is 9.5% hydrochloric acid.). Make sure you are outside or in a very well ventilated area with the right safety equipment.

Step 6: Wait for It

In this step, all you have to do is wait for the gold foils to come off the PCB. Once you see all the gold foils floating around, wait one more day to make sure all nickel is actually off the gold foils.

This process takes a few days at most.

Step 7: Extract the Gold Foils

In this step, you will need a large soda bottle that will collect all etching solution (even if it is diluted with water, it still must go into the bottle for proper disposal). Then, you should remove the PCB and scrape off any gold still attached to the PCB (you should be wearing gloves if performing this step by hand) and fully submerge it into a cup of water.

Then, add some add some water to the existing solution full of gold (I recommend doubling the amount of solution with water. Also, if you need more capacity to hold the solution, a big plastic cup should do.).

After you thin out the solution and the gold foils have settled to the bottom, pour out a little of the solution (while keeping the gold at the bottom) into a your large soda bottle. Add some more water and repeat many times until the solution is thin enough to go through a coffee filter.

DO NOT POUR DOWN SINK OR TOILET. YOU MUST FOLLOW THE STEPS ABOVE, OR RISK BREAKING LAWS WITH HARSH FINES AND EVEN JAIL TIME IF YOU ARE CAUGHT.

Step 8: Filter Out Gold Foils

In this step, pour your solution containing the gold into the coffee slowly (make sure your coffee filter is over a cup). Be careful not to rip the filter or you will have to start the filtration process over again.

Also, if the water the stripped PCBs are submerged in has gold foils floating around, pour that into the filter, too.

After filtering out all the gold, pour out the excess water into your hazardous waste bottle that will be disposed of properly, and continue to run regular water through the filter to clean the gold.

Make sure all water that is mixed with the etching solution is contained in your bottle that must be disposed of properly in the next step.

DO NOT POUR DOWN SINK OR TOILET. YOU MUST FOLLOW THE STEPS ABOVE, OR RISK BREAKING LAWS WITH HARSH FINES AND EVEN JAIL TIME IF YOU ARE CAUGHT.

Step 9: Remove the Gold Foils Sticking to the Coffee Filter

In this step, turn your coffee filter inside out over a cup and add a little water to the top. This pushes the gold foils off the filter and into the cup.

Then, wait for the gold foils to settle to the bottom and get as much water out. After that, you could wait for the water to evaporate out and you are left with just gold. However, the gold foils tend to stick to the cup, so I keep mine in a glass vial with some water.

Step 10: Dispose of Hazardous Wastes Properly

In this step, package your etching solution in a bottle with a very tight cap (if using chemical concentrations higher than what I've used, package in glass bottle. Otherwise, plastic is fine.). Label the bottle and make sure it clearly says HAZARDOUS, DO NOT DRINK OR OPEN in huge letters all over the bottle. Tape the cap with masking tape so people, if they get ahold of it, don't open it. Also, keep away from anyone else, especially young children, or any other bottles of the same kind.

Also, take PCBs and put them in a plastic bag and put into trash. These are fine to put in the trash if you have followed previous step of soaking them in a cup of water. If not, please soak in water before disposing.

After properly packaging, take to your nearest hazardous waste processing facility or H-MRF. These facilities are only by appointment and sometimes, depending on where you live, charge a fee (around $5 in most places that are government run. I don't know what the fee is for privately run facilities.).

DO NOT POUR DOWN SINK OR TOILET. YOU MUST FOLLOW THE STEPS ABOVE, OR RISK BREAKING LAWS WITH HARSH FINES AND EVEN JAIL TIME IF YOU ARE CAUGHT.

Step 11: Enjoy the Gold

You are now very rich!!!

Thanks so much for taking the time to read this Instructable. Enjoy!!!!

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188 Discussions

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Ludvic

4 years ago

Sorry but in this process you don't extract gold, the only solution can dissolve gold is aqua regia (nitric acid, and hydrogen peroxide)

16 replies

but ,the aqua regia will dissolve the gold too with the solutions

he's not dissolving the gold, he's dissolving the nickel from underneath the gold, nickel which IS dissolved by Hydrochloric or Hydriodic acid. The gold plate is left free of the substrate. Not a viable money-making process at this volume unless you manage to find your chemicals for free-otherwise financially you'd be better off picking grains of gold out of sand at the beach. Still entertaining and educational though!

I am doubtful that the hydrochloric acid content of a toilet cleaner, even boosted with hydrogen peroxide is strong enough to dissolve much nickel, I believe just the copper has dissolved. I would love to check this but I have never seen Lysol for sale here in Oz.

how about pool acid? aka 30% hcl for adjusting the ph in pools... aka (idioticly and archaicly) muriatic acid

a really common and easy source of hydrochloric acid is concrete cleaner. Get it from any hardware. But be warned, at 33% this a lot stronger than toilet cleaner and strong enough to eat your hands off. In Aus it is mainly phosphoric acid used as toilet cleaner.

About a year ago, I was looking at a cross section diagram of a PCB showing the layers of metal. If I remember correctly, touching the PCB was copper, then nickel, then the gold on top. I could be wrong.

However, after the gold was removed, copper was visible and no nickel was visible on the gold. So, either the etching solution dissolved some copper, but not all of it and there was no nickel to begin with. Or, the nickel in between the copper and gold was dissolved.

Thanks for commenting!

I left this sit for a long time but it keeps worrying me that in this world of vanishing chemists this little slip of misinformation from Dr.Bob might just get someone off course.
Some Nickel Oxides dissolve in hydrochloric acid but Nickel metal doesn't, in fact Ni's resistance to HCl is very important to industry: http://www.nickelinstitute.org/~/Media/Files/TechnicalLiterature/ResistanceofNickelandHigh_NickelAlloystoCorrosionbyHydrochloricAcid_HydrogenChlorideandChlorine_279_.pdf
I will leave aside the issue of acid getting through the gold to reach the nickel; but it is important to realize much, perhaps most gold plating is directly on the copper, particularly on older circuit boards.

Merhaba maden altin oksijenle eritilir ken içine neler atilmali

Actually HCl + H2O2 will dissolve gold. The peroxide acts as an oxidiser (HCl is a non-oxidising acid) and the free chlorine will dissolve some gold into solution. The presence of copper which is higher in the reactive series of metals will subsequently drop the gold as a fine dust. You'd be better to use the HCl + H2O2 with copper to create cupric chloride first, then one the free peroxide is used up, use that solution to dissolve the copper without losing any gold.

Aqua Regia is made from nitric acid and hydrochloric acid and is dangerous enough. Mixing nitric acid and hydrogen peroxide is super hazardous DON'T DO IT: http://www.solvaychemicals.us/SiteCollectionDocume...

Aqua Regia is the only acid that will dissolve gold but there are quite a few non-acids that will dissolve gold. The industry uses cyanide and/or mercury to extract trace gold from ore but these are both intensely poisonous and should not be tried at home. Even if you do it safely you have to ultimately dispose of the waste chemicals safely for the environment.

Back in the 70's I extracted the gold, copper and solder from from about a 100Kg of salvaged circuit boards. Even with the thicker gold used in those days I didn't get enough total return to cover the total cost of the processing. As I recall we got more return from the copper and other scrap metals than we did from the gold, still not nearly enough to make a profit.

The 'industry' doesn't use mercury anymore. It's still used in Africa and South America by locals, but any serious company will stay far away from mercury during gold leaching.

Anyway, chlorine gas is indeed nothing to play with, it's a real killer. And as said before, you better go for pure HCl, those toilet cleaners are not as pure and are thus less predictable.

@OP, any idea how pure your gold is? And have you calculated your net profit, because I suspect your chemicals might be too expensive.

I have been involved with the gold Industry for 56 years, and for a good part of that time I was designing gold production technology specifically to reduce the use of mercury and cyanide; both significant environmental concerns in my country. While free mercury use has markedly decreased since the 60's there are still table sluices in common use with mercury amalgamated with copper. The common urban myth is that mercury is totally safe as an amalgam. The issue is made more complicated by various agencies that only recognize gold assays made with an outdated standard method involving mercury. When the industry is totally free of mercury you will hear me cheer!

I don't recall saying anything about chlorine gas???

Chlorine gas comment was not specifically for you, just a general warning.

I don't know of any professional company still using mercury or amalgam alloy (which is indeed equally toxic). As far as I know they all use cyanide, because it's much cheaper as well. But that stuff is certainly not a DIY project. Feel free to share information on companies still using the amalgamation method.

The cupellation part of the fire assay is done with a lead, not sure where mercury is involved, except if it was already present in the ore?

Apparently OP answered this question below, sorry.

(22-23 carat = 90-95% gold)

You are not dissolving the gold. You are dissolving the other substances and will be left with gold. That gold can then be sold.

HELLO very good info but how much gold is the rating from each PC mother board example.?

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TC33

8 months ago

This is the first at home gold refining process that I have ever seen that is easy to understand and straight to the point. I'm going to try it. It's like making coffee or making weed oil , just its making gold. I hope. Excellent tutorial ,

Can i use TOILET Bowl cleaner which contain hydrochloric acid 9g & 5percent nonionic surfactants as insist of 9.5g...