AP Observations and Questions

[burningsuntech]

Process: AP
Ratios: 600ml HCl 31.45% : 400ml H202 3% a ratio of 3:2
Scrap content: Approx 200g Shredded boards from a cell phone, from the displays of 4 laptops, and the gold pins from 3 cpus and a few connectors on the motherboards.

AP went as expected. Got the Emerald green color of the CuCl2. I moved it outdoors because of the chlorine and the ambient temp outside was about 40 deg F. After 2 hours, the reaction stopped so added more CuCl2 to restart. Got a good reaction. I left it go for 4 hours and then checked how well the copper was stripping off the boards. There wasn't much difference. Added another 100ml of CuCl2 and got no reaction. Left it overnight. Checked it again in the AM and the color was darker but there was still a lot of copper to be dissolved. Very little of the gold stripped from the boards.

I decided to switch to Ferric Chloride for faster stripping so I drained the shred from the pot and put it in a clean plastic bowl and added tap water to rinse it before moving it to the FeCl2. This is when the water turned very cloudy white. So I put the cloudy water in another container and let it settle. It now has a beautiful sky blue color with white cloudy puffy looking precipitate on the lower third of the container.

Here is what I believe has happened. Correct me if I'm wrong. The White cloudy solution is the result of high silver content of the boards and the silver reduced the ability of the solution to strip the copper from the boards because it bound itself to the chlorine ions thereby leaving the gold still attached. So what I have here is Silver Chloride? If so then I can convert it to Silver Nitrate and cement it out with copper. If not, what is it then? I have well water here and it is very hard. Could it be a carbonate of silver? Is there such a thing?

This is not the first time this has happened. A previous attempt resulted in a greyish sediment that I filtered from the CuCl2 solution and am holding till I can determine what it is and what to do with it.

I seem to have better luck with Ferric Chloride than with The AP in getting gold off the boards. Anyone else have any suggestions?

Thanks for your input and advance. This site and the guys here are awesome!

 

[butcher]

From the materials you started with Scrap content: Approx 200g Shredded boards from a cell phone, from the displays of 4 laptops, and the gold pins from 3 CPUs and a few connectors on the motherboards.

You could have many metals in solution, and other metals being replaced from solution, in a solution of troublesome metals.

Silver will use up some of the solution as it forms an insoluble silver chloride and would settle to the bottom of the vessel with the insoluble lead chloride, but it would not stop the solutions ability to dissolve more copper into solution.

You cannot convert silver chloride to a silver nitrate easily, as you make it sound, silver chloride is insoluble in nitric acid, so unless you first convert the silver back to silver metal or an oxide of silver, and then dissolve the silver metal in nitric acid, that idea will not work.

White or grayish sediment from copper chloride, or ferric chloride solution can be a mixture of several metal chlorides, copper, silver, lead, iron hydroxides, as well as others metal salts and insoluble substances depending on what metals or other materials were involved and conditions.

You are setting yourself for a lot of problems to deal with, by adding whole shredded circuit boards, which can be a real mess to deal with, the solder added to your solutions is a good trap for values, making losing these values in the process very likely, and recovering all of them very hard to do.

It looks to me like you are going about this all wrong, just setting yourself up for one big mess to deal with.

Garbage in, and you can expect garbage out.

 

[Marcel]

Your white cloud is Cu(I)Cl it was formed as you added the water and there suddently wasn´t enough HCL (or better chlorine) left that could form Cu(II)Cl, because some chlor ions moved to the H2O2.

>shreded mobile phone PCBs in AP ? VERY bad idea... preposter told you why.

 

[FrugalRefiner]

AP went as expected. Got the Emerald green color of the CuCl2. I moved it outdoors because of the chlorine and the ambient temp outside was about 40 deg F.

Burningsuntech,

Others have already mentioned some of the problems they noticed in your process, but I'm just going to comment about this one. NEVER do these processes in your home! That chlorine smell you noticed can kill you and anyone else in your home.

Now I'll admit, you didn't say where you moved it from when you moved it outdoors. Maybe it was your garage, or a shed, or a barn. But the idea of someone dealing with a process they clearly do not understand in any closed space causes me to worry about your safety.

The first rule is to be safe in everything you do. Before you jump into thesse processes be sure you understand the potential hazards and do everything you can to minimize the risks. Read EVERYTHING in the Safety section of the forum, especially the Dealing with Waste topic. No amount of precious metal is worth jeopardizing your health or the health of those around you.

Dave

 

[burningsuntech]

Thanks for the input, guys. And thanks to Dave for the safety concern.

I have put the results of this first batch from the AP process aside to determine what to do with it later. As butcher had surmised, there are too many different metals in the mix and it will be difficult to process.

In the meantime, I have started Using ferric Chloride exclusively to take the gold off the copper. To make sure there were no other metals in the mix, I cherry picked only parts that contained gold and copper. Any boards that had silver on them were excluded. This second batch was made up of only cell phone board parts that had gold, only the pin strips of the memory sticks, only the gold foiled LCD display boards (lots of gold there) and only gold plated pins from cpu's and board connectors. This resulted in 95.11g of shred, pins and the like.

I ran this through a mixture of 200ml of Ferric Chloride and 200ml of distilled water. After 4 hours, I removed it and checked to see that the gold had been released from the copper. I then washed the shred in a separate dish with tap water and got a cloudy brown mixture that took several hours to run through a filter. Then I filtered the remaining flake and rinsed them in tap water with the same result. I set the whole batch aside overnight to allow it to settle.

I decanted the batch, washed it in 200ml of HCL 31.45% and 100ml of Distilled Water and boiled it for a few minutes. The cloudy brown mess disappeared. I cooled the mixture and filtered it with a very good result of 4.87g of gold flake mixed with fine fiber glass from the shredding process.

(Note to self: Forget about shredding and concentrate on just cutting the boards in pieces to eliminate the fiber glass).

From here on out, I think I'm going to concentrate my efforts on the Ferric Chloride process and multiple filtering processes to increase the yield. Also will use AR to dissolve the gold and precipitate it out with SMB to see what kind of results I get.

I'll let you guys know how it all turns out. Thanks for you comments, questions, and inputs. I am new and able to take the input. After all, its how humans learn. As soon as I figure out how to post pics, I'll do so.

 

[jeneje]

Thanks for the input, guys. And thanks to Dave for the safety concern.

I have put the results of this first batch from the AP process aside to determine what to do with it later. As butcher had surmised, there are too many different metals in the mix and it will be difficult to process.

In the meantime, I have started Using ferric Chloride exclusively to take the gold off the copper. To make sure there were no other metals in the mix, I cherry picked only parts that contained gold and copper. Any boards that had silver on them were excluded. This second batch was made up of only cell phone board parts that had gold, only the pin strips of the memory sticks, only the gold foiled LCD display boards (lots of gold there) and only gold plated pins from cpu's and board connectors. This resulted in 95.11g of shred, pins and the like.

I ran this through a mixture of 200ml of Ferric Chloride and 200ml of distilled water. After 4 hours, I removed it and checked to see that the gold had been released from the copper. I then washed the shred in a separate dish with tap water and got a cloudy brown mixture that took several hours to run through a filter. Then I filtered the remaining flake and rinsed them in tap water with the same result. I set the whole batch aside overnight to allow it to settle.

I decanted the batch, washed it in 200ml of HCL 31.45% and 100ml of Distilled Water and boiled it for a few minutes. The cloudy brown mess disappeared. I cooled the mixture and filtered it with a very good result of 4.87g of gold flake mixed with fine fiber glass from the shredding process.

(Note to self: Forget about shredding and concentrate on just cutting the boards in pieces to eliminate the fiber glass).

From here on out, I think I'm going to concentrate my efforts on the Ferric Chloride process and multiple filtering processes to increase the yield. Also will use AR to dissolve the gold and precipitate it out with SMB to see what kind of results I get.

I'll let you guys know how it all turns out. Thanks for you comments, questions, and inputs. I am new and able to take the input. After all, its how humans learn. As soon as I figure out how to post pics, I'll do so.

Here is some information on ferric chioride http://www.hvchemical.com/msds/fech.htmif you have not used it before.
Ken

 

[butcher]

Hot concentrated ferric chloride brine solution can be a leach for base metals, it will gobble up copper, it will also dissolve quite a bit of silver in a hot brine solution close to 90 deg C.
Cooling will precipitate the silver chloride back out, it works better for fine or powdered metals, it will not dissolve gold, and can be used to separate other metals from gold powders as a recovery method,

 

[Geo]

be aware that ferric chloride is the end of the road for this particular solution. you really cant rejuvenate it. once it turns black and stops digesting metal its just toxic waste. thats why we try to limit the iron that goes into the AP solution. copper chloride will only dissolve a finite amount of iron but it will continue to dissolve copper for a very long time as long as it isnt fouled with iron and nickel.

 

[burningsuntech]

butcher
Thanks for the tip. I'll give it a try on the fouled AP batch and see what results I get.

Geo
Thanks also.
Yeah, ferric chloride is only good for a couple of batches and then has to be dealt with.
I know I'm doing something wrong to get the results I have with AP. I'm just not sure what. My next experiment will have to be based on only gold bound copper and not with a mixture of board types and proper formula for AP.

I have found two ratios for the AP formula and am abit confused on that. One sez HCl : H2O2 of 3:2 and another sez HCl : H202 2:1. Which is best?

Any help would be appreciated. Thanks.
Pic added to show FeCl3 batch results.

 

[butcher]

I read a mining patent about a year ago, an article where they were rejuvenating the ferric chloride with by product gases from the process, the gold silver and some base metals were from a cyanide leach cemented with zinc, the gold was separated using the ferric chloride leach, and byproducts of the process (I believe they used the gases from AgCl were used to rejuvenate the ferric chloride), I cannot remember details, it wasn’t something I care to try or do. but I can try and find the patent again.

Normally ferric chloride is not rejuvenated (I am unsure how to or if it can be done effectively.

I have used ferric chloride to dissolve base metals, like copper plated pins and copper from silver contacts, and so on, mainly copper, using it as an aggressive way to dissolve copper and was very surprised how much copper it would collect into the hot solution and hold, my goal was not so much to keep the copper in solution as it was to break the large volume of metal down to copper I chloride, and other metal chlorides, after the brine dissolved as much copper as it would hold, I would move the brine to a cooling jar add a little water and a splash of HCl, let the brine cool and copper chloride precipitate out, the liquid I would return to the hot leach.
After I had a jar full of copper I chloride powders mixed with gold plating foils and powders, I would dissolve the copper I chloride in HCl and a little peroxide leaving the gold foils and silver chloride, the recovered metal would get further processing, the copper II chloride solution was filtered and could be used for the copper II chloride leach ("acid peroxide leach").

 

[butcher]

burningsuntech,

You should study the document on Laser Steve's web site it explains the leach in great detail, while your there you may find the ratio he suggests.

Ratio’s? Sorry I am not sure which would be correct, I do not use ratios I just pour some in, going by colors and what I observe, and how the solutions react.

I begin with HCl and copper, and add a little 3% H2O2, if its light green let it dissolve copper, add air from fish tank air pump, if it gets dark green-brown, I will add some H2O2, if it forms white copper I chloride powders, I will add a little HCl.

 

[kkmonte]

IIRC, Steve recommends 2:1 ratio of HCL to H2O2.

 

[Geo]

the H2O2 is just to jump start the process. after a short time the extra oxygen is used up and all thats left is H2O. you could add some copper chloride from a previous batch and bubble air through it and get the same results. you only add the H2O2 once if your using an air pump. adding peroxide over and over will dissolve some gold. i set aside a gallon of pregnant leach just for that purpose. when i have to start a fresh batch (and this is just my preference that works for me) i add 1 gallon of hcl and 1 quart H2O2. after you do it for awhile and get used to what all it can and will do, you learn what to expect. i still get surprised ever so often.

 

[burningsuntech]

I read a mining patent about a year ago, an article where they were rejuvenating the ferric chloride with by product gases from the process, the gold silver and some base metals were from a cyanide leach cemented with zinc, the gold was separated using the ferric chloride leach, and byproducts of the process (I believe they used the gases from AgCl were used to rejuvenate the ferric chloride), I cannot remember details, it wasn’t something I care to try or do. but I can try and find the patent again.

Normally ferric chloride is not rejuvenated (I am unsure how to or if it can be done effectively.

That would be interesting, butcher. But only if you happen to stumble upon it again. It sounds too complicated for the home operation.

I had a convo with a chemist friend of mine and he suggested using a form of reverse electrolysis? to cement the copper to a graphite electrode and use an iron electrode to replace the lost iron thereby rejuvenating the ferric chloride. He did say, however, that nothing is 100% and that after a few dozen cycles of this process even the remaining liquid would be much worse to dispose of in that it would be too toxic to handle. I would tend to agree. As much as I like the FeCl₃ process, I'm beginning to see the wisdom of the AP process.

Thanks for the answers. The discussion is really interesting and I'm glad you guys are willing. I'll post results of my next run in the AP process and see if the yield is better with just gold bearing copper than with just crushed boards. :mrgreen:

 

[burningsuntech]

IIRC, Steve recommends 2:1 ratio of HCL to H2O2.

Thanks kk. I'l work with that as a start.

 

[burningsuntech]

the H2O2 is just to jump start the process. after a short time the extra oxygen is used up and all thats left is H2O. you could add some copper chloride from a previous batch and bubble air through it and get the same results. you only add the H2O2 once if your using an air pump. adding peroxide over and over will dissolve some gold. i set aside a gallon of pregnant leach just for that purpose. when i have to start a fresh batch (and this is just my preference that works for me) i add 1 gallon of hcl and 1 quart H2O2. after you do it for awhile and get used to what all it can and will do, you learn what to expect. i still get surprised ever so often.

To say you get surprised... I havent had a consistent test yet. lol. And I know why... I'm my own worst enemy in chemistry by changing to many variables at a time. (shame on me ) But I'm re-learning and having a lot of fun.

I'll keep these tips in mind Geo. Much thanks, bud.