Reclaiming precious metal from circuit boards, etc.
Q. I work for a semiconductor research group and we do evaporations of precious metals as interconnects. Periodically, we clean out the evaporator and over the years we've collected several pounds of mixed metal. I'd say it's about 80% Au and the rest is Ti, Pt, Pl, Ge, Ni, Cr, W, and maybe a trace of other stuff. All the metals are from 99.9999% pure sources (not that it matters any more).
Anyone know of a place to refine or buy this stuff?Dennis Scott
University of Illinois - Urbana, Illinois
A. Dennis, try
Harry van der Zanden
- Budapest, Hungary
Q. I was a plating chemist for several years and recently have come into a quantity of surplus Gov. computers.... all outdated. Is it worth the effort to try to reclaim precious metals from them? I am not currently set up with a lab.Greg A
- Toccoa, Georgia
Q. I have a set of connectors out of a surplus computer control. They are gold plated with roughly .005 thick plating. I'm trying to find someplace to sell them. Any help would be appreciated.Robert S
- Carlton, Oregon
A. That must be a very very OLD computer, Robert; the thickness you describe is more than 100 times as thick as today's standards :-)
If the gold really is that thick, some say you can scrape it off with a razor blade. Sounds like it's worth trying. Good luck.
But there are stores that buy gold in most cities, and you can find others on the internet googling for names like "cash for gold".
Ted Mooney, P.E. RET
Brick, New Jersey
Q. As do Greg A and Robert S, I am in possession of a large number of old computers. Can anyone tell me if it is worth reclaiming the gold from the circuit boards and connectors and if it is how do I go about it. Thank you for any information you can give me.Carl P
- Damascus, Maryland
A. Carl Probert,
A lot depends on the age of the computer. When gold went to $800 in the early 80's they started using far less gold. The gold occurs in 4 areas.
Silver also occurs in tantalum capacitors and multilayer capacitors.
To refine the boards you must prepare them by removing all non gold material, batteries, steel, aluminum etc, why pay to refine stuff that has no gold.
If you have a truckload, go to Noranda Smelting in Quebec, they are lowest cost. For small amounts materials use Johnson Matthey. they charge $2 per pound, so clean it well.
Do not use any small refiners owned by families or otherwise privately owned. They usually cheat you since you have no recourse. Make sure you get a referee to get your samples. Make sure he knows what it means when you run the furnace too hot. It means gold sublimes from the melt and condenses on the oxide particles and end up in the air filter....you get no money for that. make sure you sample the waste oxide and crap that floats to the top from the furnace....it has gold in it and the refinery send that out and keeps that credit unless you ask for it.
If you have less than a few hundred pounds it is not worth it....just sell it to a broker. BillBill Jackson
- Toronto, Ontario, Canada
Thanks for the helpful info, Bill. But 'usually' is a pretty strong word in that context.
Secrets of Gold Recovery from Electronic Scrap
Recovering Precious Metals
Refining Precious Metal Wastes
Q. I have a 55 gallon drum with remnants of material obtained in the clean up of semi-conductor machines. Does anyone know what the value of this would be? Is it worth my while to pursue this?Scott Miller
- Las Vegas, Nevada
I would like to respond to the people interested in electronics recycling, I have been recycling computers and other gold bearing electronics for 12 years, I started out by sending my material out to be refined, after several years of being cheated and sending material from one place to another I learned how to do it myself, I have now been reclaiming the gold and other precious metals myself for 10 years. It does pay to recycle electronic scrap!
Any questions I will gladly answer.Arnold Hoskins
Q. This is for Arnold Hoskins, I am very interested in removing gold from chips and circuit boards, and then refining it myself, where can I get some more information beside the Shor company,
- Chico, California
I would be interested in your methods. I have done a little with Aqua Regia and the glass/borax finish method, but have not had good luck with electronics scrap. I have monthly access to an average of 3-500 "old" pieces( 8086-486) that have no real value other than possible material reclamation. I would like to secure any good methods you have that work specifically with this type of application.
Thanks,Richard P. Alcorn
- Cordell, Oklahoma
Q. Mr. Arnold Hoskins,
I am also interested in learning more about your methods for electronics recycling. There is not much information available for efficient precious metal reclamation. Any information you provide would be very helpful.
Thanking you in advance,Ed McBride
- Prattville, Alabama
Q. Mr. Arnold Hoskins,
I was very interested reading your posting. I have a availability to several hundred dead boards and I have been cruising all over the net and all I seem to find in regards to this is for extremely large corporations. Any information that you could give me in regards to electronics recycling would be greatly appreciated sir.
- Gilmer, Texas
Q. Anyone could help me how to refine precious metal from PCB? Mr. Arnold Hoskins, in Hamilton, Oh, whose story is same as mine. And I like to learn how to do it myself.Ivan Young, Lee
- Boroung-city, Korea
Mr. Hoskins hasn't been around this page for a while, but maybe someone will help. How much refining experience do you have?
Ted Mooney, P.E. RET
Brick, New Jersey
Q. Would you do me a favor.
As I mentioned on my mail, I am looking for a person who can show me how to refine precious metal from PCB. I like to build up a Burnout burner(=furnace) can handle approx. 2000 lbs a day.
Ball mill for that volume. after burn and grind, electronic refining for Cu, Ag and do Au in this order at last whatever the left over slimes, will do for Pd, Pt. Of course, I understood that it will not be a free.
Please, kindly advise me .
Thanks..Ivan Young, Lee
- Boroung-city, Korea
Q. Dear sir,
I'm running my own small refinery. Wherein I do refine gold using aqua regia process. After reaction in aqua regia , gold is precipitated by SO2 gas or Na-metabisulphide.
I'm getting the gold in powder form. but the problem I'm facing is I'm not getting the desired output. i.e the problem is if I have 10 kgs of 99.5 gold which is to be refined to 99.99 to 99.9 depending on requirement. By this I should get 9.95 kgs. of gold but I get 100-150 gms of gold less. I have checked all the process thoroughly several times . But I haven't found anything that is recoverable. Only the thing where I can check is the spent solution and wash water of gold powder. So I wanna to know about this process of recovering the gold from spent solution and wash water. Expecting your kindly answer as soon as possible.
Thanking you, regards,Suraj Sharma
- Shirpur (Dhule), Maharashtra, India
Chemistry of Gold Extraction
A. Suraj, gold does not simply vanish. Possible solutions: The gold is not really 99.5% pure to start with. Not all the gold dissolved and some is in the residue after filtering. The gold drop was incomplete.Chris Owen
- Houston, Texas
Q. Stripping metals from chloride solutions .
I recover gold from electronics. The only acid I use is aqua regia (HNO3/HCL). After precipitating the gold out of the solution, I have been adding aluminum to facilitate cementation of the remaining metals. The problem is that the Al is still in the acid at the neutralization stage.
Can I, instead of the alchemist-like Al cementing method, use electricity to strip ALL remaining metals from this chloride solution? I would appreciate advice in getting this process going. I have power sources ranging from 6V DC up to 24 V DC. Thank you,William E
electronics gold mining - Midland, Virginia
November 20, 2011
A. To Mr. William E:
I have been involved in recovering precious metals for some time now on a small scale. I am very interested in recovering the valuable materials out of circuit boards on my own without having to be cheated. There seem to be more and more criminals out there who are ready to take advantage of the hard working honest man.
In answer to your question I read somewhere about an electrolysis method that used a chemical bath and rods inserted into the end of the container that would attract the gold particles to it once the waste material had been dissolved. I am sorry I don't still have the link but I am sure that a little google research will turn it up.
I would be very interested in sharing any information we find on the subject that will help us in our goals. Together we may have a good chance.
Please reply and we can succeed together.
- Stanley, North Carolina, USA
Q. I need information and sources of chemicals needed for small to medium scale recovery of gold, silver, palladium and other precious metals, primarily from electronic scrap materials.Gary Boehm
precious metals recovery - Hamilton, Ohio
February 14, 2008
Q. I have a truck load of Circuit Boards with gold, does any body know of a company in CA that can recover the gold for me.Adrian Torres
- Corona, California
February 14, 2008
A. Hi, Adrian.
Crutchfield has a neat little widget at http://www.crutchfield.com/environmental-policy/recycling.html that will help you find recyclers.
See also letter 18889 for more discussion on recovery of components and precious metals from electronic scrap.
But you are asking who can responsibly recycle these circuit boards for you and give you money for them rather than it costing you money, and the answer unfortunately may be nobody :-)
E-waste is a huge environmental threat, and amateur recycling is a wrecking ball that scatters toxins everywhere, so you won't get co-operation from government or environmental groups. They want you to pay for responsible disposal, not to expect to get paid for it. Sorry.
Ted Mooney, P.E. RET
Brick, New Jersey
November 20, 2008
Q. Hi All,
I work for a waste management company that has developed a process for PCB Recycling in 3 steps:
-Surface gold (fingers, connectors...) recovered by cyanide stripping and electrolysis.
-Removing of components from the board.
-Crushing and gravimetric separation of the copper and the resin/fiber glass from the board.
Now I am left with the components that I have to send to a refiner.
I would like to do the refinery of Gold from IC chips in-house.
The process that I have tried is as follow:
- Heating to make the Chips brittle
- Grinding in powder
- Dissolution of most metals (mostly copper) in Nitric Acid. (no additional heat)
- Dissolution of Gold in Aqua Regia (+heating)
- Precipitation of Gold with SMS
I managed to get a small % only of the gold from the original chips.
I am looking for technical advise to improve the recovery rate..
Is the process workable?
What would be the ideal qty of chemicals for a typical IC (20% Cu, 0.1% Au)
Thanks for your help.
November 5, 2009
Q. I would like to have a gold reclaiming process( fingers/ P.C. motherboards) a non-chemist can follow. A simple and safe process please.Eric McGhee
novice - Omaha, Nebraska
Ed. note: See also letter 18889 for more discussion on recovery of components and precious metals from electronic scrap. Also, put the term "gold recovery" into the search engine for many more discussions. Many people seriously question whether a safe process exists.
May 17, 2010
Q. I am interested in stripping boards of their precious metal content using an electrolysis process. I am also a total newcomer to this subject. As I understand it, the electrolyte solution must also contain a salt of the metal that is being stripped, to start the process. As gold may be all over the place and in tiny areas of the board, I'm interested in knowing if there could be a substrate that could be applied to the entire rear of the board, making contact with all of the solder points, and in effect, turning the entire PCB board into a cathode once power is applied to the metallic substrate backer board? Would a copper sheet pressed against the rear of the PCB and affixed with clamps possibly work?Dan Andersen
- Port jefferson Station, New York
April 25, 2011
A. I get the feeling that most people that end up here are looking for quick, easy answers. I have been studying various aspects of E-Scrap precious metal recovery and come to some conclusions. One being that there are no quick, easy answers. Everyone wants to get rich or make a bundle on gold scrap recovery. Unless you can deal in large quantities ...OR...buy scrap gold directly from people such as pawn shops, etc., you're going to spend more on equipment and chemicals than you will yield at .999
Let's say you process 100 computers at a time, chances are whether you do the refining yourself or pay to have it done, it's not going to be cost effective or you will have such low yields by not having the proper processing equipment. Goldmining computer scrap is not going to make you rich ... unless, you process several tons a week of CPU's. Printer boards are only worth the copper, tin and some lead or aluminum. You have to deal in quantities to really make a go at it. With that being said, if you are steadily collecting and acquiring early to mid 90's computer boards and chips and you carefully harvest every component from each board, then you might have something to appreciate a year or few later. So many people are driving up the prices of computer scrap thinking this is going to be the big one...but you end up having less to shine that the coins you paid for it. Make no mistake, if you are paying top dollar for computer scrap, you've already lost your profit. Scrap steel from cases are useful ($0.08/lb), copper from transformers and motors is worth $0.22 per#, Aluminum heat sinks are worth about $0.50-.80 per#, CRT's are revenue negative if you are processing small scale. Platinum, silver, rhodium, palladium...everybody wants to ask someone that knows how to get it and what to look for. Unless you spend some time working in a refinery, chances are you won't get the full scoop...just bits and pieces. Unless you move truckloads at a time to refineries, you won't come out on top. What kind of health risks are you taking breathing sodium cyanide fumes and other noxious deadly gases -- hope I don't live next door to you, neighbor!
Research & Development - Lubbock, Texas
March 24, 2012
Q. This is my first time posting, so hello to all. I've done a lot of reading here as well as on other sites. I've read a lot of comments from people warning others to either be very careful or to not even get involved because of the associated risks. I believe that if these people issuing such warnings didn't give a damn, then they'd not be wasting their time issuing such warnings, and it's nice to know that people do care. With that in mind, I just want everyone to know that I'm not taking any of these associated risks lightly. If I were, I wouldn't be here now. I guess the short statement would be, "I'm only going to do this once I'm 100% sure it's being done right."
I noticed, at the top of the page, on the right, there's a list of products, entitled, "Right now on Ebay". The next to the last on the list is a product I actually bought a few weeks ago. I would be interested in hearing back from anyone out there who is familiar with it. The seller always answers my emails, and in my opinion, is doing his best to stand by his product. The included instructions are a little bit hard to follow, sometimes, I think because English is not his first language. The kit comes with a scrubber that neutralizes the fumes and gasses. I went 1 step further though and bought a fume-hood just in case anything goes wrong with the scrubbing process. I'm slowly accumulating everything needed...waiting on things like pyrex beakers, filtering flasks, stir sticks, Etc...Thanks, in advance, for any enlightenment,
IT Support - Rockland, Massachusetts, USA
Ed. note: Those Ebay ads change hour-by-hour as old items sell out and new ones come on line, Michael, so we don't know which item you bought. It's just as well because we don't print testimonials for a long list of reasons that would bore you ... but they include the fact that we receive countless "plants" by salespeople claiming to be satisfied customers :-).
Sorry, but please try to restrict questions and recommendations to technical approaches, not particular vendors. Thanks.
August 25, 2012
I want to know how we can refine gold from rhodium in gold plated rhodium?
Asia Goldsmith - Esfahan,Iran
September 16, 2012
A. Is there anyone here that could send me detailed instructions on extracting gold chemically? I've watched loads of vids and read some but I can't find anything with details/cautions? Someone has to have the whole thing together.
Thanks a Bullion!
- Innisfil, Ontario, Canada
September 18, 2012
Hi David. There are instructions on ebay (that I'm not vouching for) that claim to tell you what you need to know. We listed 3 books that pretty much have "the whole thing together". Have you located and taken a look at them? We have a dozen threads on the subject just on this site. The thing is, you are learning with everything you look at, and that's good!
But it may be asking too much to expect step-by-step instructions which people of unknown experience and knowledge can follow. Consider: most people had a year of chemistry in high school but some didn't (or don't remember it), other people have several years of chemistry in college and beyond. What should be the chemistry prerequisites for the particular set of instructions you're looking for?
As for general cautions, the first rule in chemically-oriented industries is that you never ever ever work alone... not for one single minute, not for any reason. Are you strictly adhering to the primary rule, or are you throwing out the very first and most important rule before asking for more? :-)
Ted Mooney, P.E. RET
Brick, New Jersey