# What to do with Acid Peroxide after removing the gold foils



## lazersteve (Nov 8, 2009)

All,

Recently I have had many questions about dissolved gold in spent AP solutions. I have also had many questions about what to do with old AP solutions. For this reason I have decided to summarize information that I have posted in the past into this single post.

Here is what I've stated in the past about left over AP solutions:

The black powder must be removed / filtered out before adding any iron to the mix. Once iron is added the copper will precipitate and the solution is no longer usable.

To get gold out keep dissolving copper based items (fingers, some non-magnetic types of cpus and pins) until the color of the solution turns nearly black. Once the AP solution is black there will be no gold dissolved in the solution. At this point let it settle 24 hours and filter out the fine black powder (gold + contamination) Refine this material with HCl-Cl to get your gold back.

After the gold has gone into solution don't expect to see gold flakes any longer, only black powder as the copper saturates the solution. Gray or off white powder in the bottom of the bucket is a sign of copper I chloride saturation.

After you remove the black powder from the solution and confirm saturation with a few drops of tap water (a white cloud forming indicates copper I saturation), you should decide how much of the saturated solution you want to save for recycling in the next batch. A final test with stannous will confirm no gold is present. 

Pour off the solution you don't need into a separate bucket and add in a large surface area piece of steel (zinc plated is fine) to push the copper out of the solution. Scrape the copper off of the steel plate periodically to expose more bare metal to the solution. 

Here's a photo of me harvesting copper from one of my spent AP buckets today:








Once all the copper is out, remove the steel plate.

The solution is now a greenish rusty brown. 

Here's another photo:






Add lime ($4.50 for forty pounds at WalMart) dissolved in water until it turns clear and test pH 7 to litmus paper. The solution foams vigorously as the lime water is added. The neutralized salt water can now be disposed of without worries. The red brown iron compounds in the sediment can be dried out and sent to the local dump or melted with carbon to form crude iron.

Clean up the copper with several dilute (5%) HCl rinses and finally with two or three water rinses. Let the copper powder dry under a heated vacuum or with forced heat (direct sun works fine) to prevent green copper carbonates or brown/black copper oxides from forming on it's surface from air exposure. Store powder in an air tight container.

Here's what properly washed and dried copper powder looks like:






The remaining solution (the part you did not add the steel to) should have air bubbled through it until it turns emerald green again. If it's color doesn't lighten after 24 hours of bubbling add a cup of ~32% HCl and 1/2 cup of 3% peroxide. It is now ready for reuse on your next batch of fingers.

You should study the copper chloride document on my website in the documents section.

All of the above information is already posted on the forum in various older posts.

Steve


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## markqf1 (Nov 10, 2009)

Thanks Steve,
Here is a company that claims that they will buy the copper powder.

www.calchemmetals.com

Mark


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## markqf1 (Nov 11, 2009)

Steve,
Would that copper powder be suitable to use for cementation of pm's from solution?

Mark


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## lazersteve (Nov 11, 2009)

markqf1 said:


> Steve,
> Would that copper powder be suitable to use for cementation of pm's from solution?
> 
> Mark



Never tried it, I suspect it may be. I don't really like the idea of cementing PGMs with copper since it's harder to rinse out than zinc. 

I'm saving all of my copper so I can melt it into bars for silver recovery.

Steve


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## butcher (Nov 11, 2009)

What I have noticed you can precipitate the metals out of solution with fine copper, but there are many problems, in a concentrated solution the metals lower in series than copper (values) will plate to the copper powder in solution and may stay suspended in this salty mixture not precipitating (colloidial solution), they can also be contaminated with other metals that the Iron or metal that was used also precipitated, this can complicate a solution, making it even more of a problem, also if the copper does make a good precipitation it will be contaminated powders and doing washing proceedures to try and dissolve the copper without disolving the metals you want to keep is a hard juggling act, reprocessing is the about only option. even with problems noted I will sometimes use the powdered copper, but do not recommend it.

using bus bars or solid copper is much better, and in some instances if there is silver on it a plus. as the solid metal will just dissolve enough metal in solution to replace, and precipitate the values below it in series, you will need an acidic solution but not much oxidizers as too much just adds more copper to solution.

as steve wisely noted many times zink is better easier to clean up as it is so much higher in series. other times Iron will be a better choice. depends on the situation.


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## glorycloud (Nov 13, 2009)

Where is a good place to find a copper bus bar? Any suggestions? 8)


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## lazersteve (Nov 13, 2009)

From a scrap yard or ebay if you are willing o pay for it. You can also pour your own if you are set up for it.

Steve


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## butcher (Nov 14, 2009)

Copper buss bars easily can be found in old circuit breaker panels, they are the bars that supply power input to the breakers, also large breakers or other electrical equiptment has buss copper, or large copper grounding buss bars, you will find some silver plated, electrical copper is usually really pure, being electro-refined, copper pipe has more impurity's, but if clean not too bad, since using copper to replace values from solution is usually done in replacing silver or palladium from nitric, or when displacing values from a chloride solution already green containing copper and other base metals, using copper pipe is fine if clean, can take a new piece of say 6 inch copper pipe , use hacksaw dremel etcetera and cut it long ways unroll and flatten it out, a hole drilled for wire to hang it in your buckett...

If your solutions of gold chloride, and such are fairly clean of base metals, a ferrous sulfate, or one of the sulfite's,or SO2 gas,etc., would be better to use to precipitate your gold, if contaminated, rerefining again will be best, save using copper for more of a recovery from contaminated gold solutions, or to get that metal missed in your stock pot.


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## glorycloud (Nov 15, 2009)

Perzactly what I was looking for! Thank you kind sir! 8)


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## Chumbawamba (Dec 28, 2009)

You should be able to get copper bus bars from your local hardware or electrical supply store, no?


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## butcher (Dec 28, 2009)

ask an electrician, trade him something, he likes tools, ask him to also save you the silver coated bus bars he would just sell them to the scrap yard as copper, give him just a little more than the scrap yard and you will both be happy.


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## PreciousMexpert (Dec 28, 2009)

Can this copper oxide be sold to people who work with ceramics for pigments


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## Anonymous (Jan 20, 2010)

lazersteve said:


> All,
> 
> Recently I have had many questions about dissolved gold in spent AP solutions. I have also had many questions about what to do with old AP solutions. For this reason I have decided to summarize information that I have posted in the past into this single post.
> 
> ...



Steve, 

Really, thanks for taking the time to lay this out. I'm new to this hobby and my biggest concern has been generating waste and this will help a lot. This forum has so much info now it's hard to sort it all out and do a narrow search. I've already spent countless hours crawling over this forum, watching your videos, researching some basic chemistry, and of course reading Hoke's book. 

I'm working on a batch of cell phones now and things are going great. A first test (24 hour soak) with AP yielded a nice emerald green solution with lots of gold flakes floating around. I have a lot more boards to clean off then in they go. Hoping to get between 5 and 8 ounces out of it all, but time will tell. I'm also being very careful to pay attention to traces of gold left in each phase along the way (particulate or solution). Will post my results on the board here when I'm done. 

Thanks again.

Brian
Manassas, VA


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## rfd298 (Jan 27, 2010)

bmagnanimous said:


> Hoping to get between 5 and 8 ounces out of it all, but time will tell.



Brian,

How many tons of boards do you have if you are expecting 5-8 oz? Just curious.
Best of Luck!


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## Chumbawamba (Sep 8, 2010)

rfd298 said:


> bmagnanimous said:
> 
> 
> > Hoping to get between 5 and 8 ounces out of it all, but time will tell.
> ...



Perhaps they fell over on him :shock:


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## texan (Sep 9, 2010)

The majority of PM's in cell phones is hidden in the integrated circuits. The gold on the boards and the sometimes many gold plated components are just the low hanging fruit.

Texan


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