Acid Peroxide Process Information Thread Q & A's

The purpose of this thread is to begin to consolidate the vast amount of questions and answers related to the Acid Peroxide (aka AP) recovery process.

First and foremost, the name for the process, Acid Peroxide is a misnomer as the active ingredient is actually copper II chloride (CuCl2), so it should have been called the Copper II Chloride Etching process. Once the copper II chloride (C2C :idea: ) is formed it is reusable indefinitely if you take care not to foul the solution. Once formed all you need is air, HCl, and water to keep things going forever using the same solution. Your only problem will be the ever increasing volume of the C2C solution and it's proper disposal.

Secondly, C2C should be used primarily to remove copper from gold bearing scrap before attempting to digest the gold. If the plated scrap is magnetic (kovar or iron/steel) then AP (C2C) is not the process to use.

The last key note is that if you use too much hydrogen peroxide (3%) to initally generate your copper II chloride you may dissolve some of your gold into solution. If you think more is better and add too much too quickly or use too high of a concentration of hydrogen peroxide you will dissolve gold. The peroxide is a catalyst for the reaction, not the active ingredient. If you do this then simply keep using your AP as directed without adding any peroxide until it becomes saturated with copper and the gold will cement out on it's own. There is no need to add any other precipitants to the solution and doing so will foul the solution.

If you haven't read the Copper II Chloride etchant document on my website in the documents section now is the time to do so. You'll be light years ahead of the game as to what to look for and what the various colors of the solution indicate. You'll also have all the chemistry information you could want on the topic.

Now to the consolidation of previous Q&A's on the topic:

• Learning AP: AP Acquaintance Test Setup
• AP Common Facts: Acid Peroxide Notes
• AP Q&A: Acid Peroxide Help
  • AP Cleaning Foils: Gray Powder in Foils
• AP Waste: Dealing with Excess AP
• Summary of AP Clean up

If you are a visual learner then you can watch the Acid Peroxide videos for free on my website or you can buy the full length DVD: Processing Finger Boards with Acid Peroxide at my web store, it's the first item on the list.

This post is a work in progress and will be updated as I have free time to consolidate the information scattered across the forum.

Steve

Hello, Steve,
I am wondering if 32% muriatic is good enough to try this method?
I have five or so pounds of board pins (mixed with solder from removal)
if i try to get the gold from these pins, will there be any problems with the solder?
I did clean much of the loose solder out of the pile....2-3 lbs.
These are the results of 100 motherboards give or take.....
Nitric acid is severely restircted in canada, im looking for a way that excudes it from the process......
Will it be ok to simply keep adding pins and keep the pot hot till they are all stripped?
What quatitiy of combined liquid would dissolve this pile of pins?
Will it strip fingers too?
(i have about 5 lbs of them too.....)
What if i keep the pot boiling after taking out the pins and simply add the finger pile?
Will all the gold precipitate out into the black powder?
One more question,
how to mix the two chemicals....?
slowly add the preoxide when cold? then heat to strip?

32% HCl is fine.

Pins with solder will be slow going in AP, but as long as they are copper base, they will strip.

I use the sulfuric stripping cell for larger batches of pins.

Steve

Steve, is there any additional video included in your processing fingers dvd other then whats on your website? Also do you have a downloadable option in an iso format for purchase?

Moo,

Sorry no downloadable content.

What other information do you seek on video?

Several of my other DVDs cover various generic refining and lab techniques applicable to all sorts of scrap.

Despite the fact that I title and sell my DVDs by specific scrap types, many of the techniques demonstrated on the various DVDs apply to a broad spectrum of recovery and refining scrap processes. The primary focus of the DVD's is the titled subject matter, but I place many gems of information among the videos.

Steve

is the ap method usefull with gold filled jewellery? that usually has copper, brass, tin, lead, or silver in its core? or is this method only usefull with cpu chips and fingers?

Gold Filled is best processed using 50/50 nitric acid followed by AR on the resulting foils after filtering.

I sell a DVD on my webstore (link below) demonstrating the entire process for gold filled scrap.

Steve

Well yer gonna laugh i think....
I get muriatic acid from the recyclers...they give it to me for free....
The trouble may be that it doesnt store well???
Some of it is clear and fumes, and other stuff is yellowish and doesnt fume.
so much...
Anyways, i put 25 telephones into Acid with peroxide and boied for hours...2-3
The resuts were that the gold is gone from the boards but i get no yellow flakes out of the acid either....
I smashed the cell phones flat with a hammer breaking all the chips and stuff off of them before boiing.
They were flattened pretty good too....
The stuff i broke off i will treat for gold later(and other stuff too if possible)
The remaining acid must have the gold in some kind of solution as i have filtered it well and theres nowt much oin the fiters either..
I have another batch that did this too which i saved all the acids separately.....
So far i got fingers off successfully in onme batch,but notning much oin the last three using fresh acid every time too.....
How do ou precipitate the gold out?
thNKS PALLY

Processing whole boards (even if crushed first) with Acid Peroxide is frowned upon. You will likely have to cement the values (if shown to be present with a positive stannous test) on solid copper buss bar to recover the values and start from scratch with the cemented values.

Steve

Hi Steve...
I didnt know about the frowned upon part....hope im not screwing up too badly here....will desist that method for beaten phone boards.........
On the other hand, i do have some 500 of them to process right now...and would like to get the gold silver and etc pout of them....this was a test....
One reslult was the boiled boards lost their surface coatings to some extent.
Two boards were actually gold plated on both sides completely, and lost the varnish...after which they lost their gold when i replaced then after scraping....
For the whole mess of phones, plus the left overs of the last unsuccessful batch(i got nothing out of that one)
I have a small amount of grey powder drying in the acid filter.....hardly a flake of gold....
And also i got the residue from the bath which is in three roughly) parts...
Black grainy remains of squashed chips....coarsest grains...
A spakly residue thats about middle wieght, and a white reside like very fine white sand, but very very smaall particles....
These are separated by tapping the bottom of my gold pan in which i panned out the varnish residues....

I take it theres two to three kilos of silver in a (cell phone /ton....)my term....so where would the silver go also?
Is it the white small particles in the pan....
(bearing in mind i am talking about a very small amount of material in a small finnishing gold pan 6 in bottom)
I have to date cooked off about four pounds of solder and pins, netting nothing, also a couple of batches of memory and cold cpu board with the fingers left on....
(But the chips cut off..i have these separated.)
25 cell phones
Thoe only gold recovered so far is the fingers i cooked first batch.
so i have a gllon + of Hydrochloric acid which i filtered out and kept in separate batches.....
can i just mix it all up and chuck a copper bar in to suck up the gold ?
if so will i also get the palladium silver and or platinium with it ?
and finally Can this off colour acid stuff be reused for more batches?
or how do i purify it or neutralise it?
I must appologise, i guess i just jumped in with both feet....i do that...
I have wrecked 200 computers and have 100 cpus waiting for nitric acid from supplier....
The steel goes to scrap
The copper also
aluminium heat sinks are valuable also...
cell phones i get for 50 cents each from a source for fifty or so a week average...
I pick up at five computer stores and three second hand stores every friday....it sort of snowballed from the watches.......
The junk gets fixed or scrapped....
i have saved some remarkable junk from time to time...
i pods lap tops, stereos, toasters...you name it...
I give aa lot of it away for the fun of it too....
also i prospect and pan gold that way....
Oh the watches?
I bought a whole tub of watches at a swap meet....thinking of blowing the plating off
But i fixed w wholebunch and now i supply three second hand stores....
they are my donations...
But i still get tubs of these things....five to date...
so have a huge stock of watches to blow the gold off of...
I realise its not all pure gold , but will refine it electrically later maybe...
You probly think i am nuts but this is just what retirement worked out for this ole logger...
though i still have a skidder(666) in the yard, im getting too old to log and the forest is worked to death here....
Anyways any info wouldbe a help...im having fun however.... :lol:
thats enough for now...i guess....any answers would be great....
i appreciate your help in this thng...i am poorly educated in chemistry math and stuff...but capable of causing great eceological damage if left to my own ignorant designs....
Why by the way do you not cook boards?
It even took the gold plating off the two entirely goldplated boards after i scraped off the varnish bubbles....(grean icky flakeystuff)
thanks for any help in advance...
pally

Study the forum before you proceed with any processing until you understand what to do, and what not to do. That is the best advice for you at this point. It isn't as easy as giving you an answer. You must understand the fundamentals. Hoke's book will teach you the fundamentals, make sure you read that until you understand it. The forum will teach you some more modern processes.

Jim

It sounds like you have wasted quite a bit of material so far with nothing to show for it. Do what jimdoc suggested and read Hokes book and study the forum . you need to know and understand what you are doing or you will continue to have disappointing results.

Not too dissapointed so far....
I have an eightth of an ounce of finger flakes....
And who knows what all ive cemented out of my acid onto copper....still doing that...
Plus i have been doing a bit of experimenting with HCL....
It seems to take the silver plate off of spoons and such fairly well....(i just have copper left showing, and some blackish residue in the acid pickling juice...(i just have to figure how to get it out....
And so i did some golden pate spoons in another HCL bath...it lost its plate in 24 hrs...so i have that acid with some gold in it to get out too....though i can see gold floating in small pieces in it...so will filter first.....
The copper ingots with gold on em will be plated onto a pure gold piece to get a solid chuink of straight gold.
At least thats the course for now...
besides reaading up a bit morethat is....
must find out what happens when you try to get the silver out of the acid....i assume its silver chloride and im thinkin itl make chorine gas maybe...so its up in the air right npow...
maybe itl precipitate out with the aaddition of some other chemical...
anyways it sure fun doing this stuff.....

Pally,

Hoke's book if you are serious.
Dealing with waste in the safety section, also reading this section may keep you out of the hospital.

my apologies. I started with the usual 3:1 ratio of HCl to hydrogen peroxide. I let it sit for 2 days while in between those days I added a little more peroxide to get a better reaction. I drained the ap from the board components that the gold came from and now I can see pieces of the board I processed finely mixed in with the gold flakes. How can I remove the pieces of the board, or when im smelting the gold down could I remove the waste from the mixture? This is my first time and Im just trying this out on a few cell phones but just wanted to get the kinks out before I try on my 5 1996 and earlier computer brains.

You can dissolve the gold with HCl/Cl and then filter. This will allow the gold to pass through and the debris will be trapped in the filter.

Guys, this whole AP process seems to be a huge waste of time and materials. Currently I'm stripping gold foil from cpus using straight Nitric acid and it works fine each and everytime. Whenever I introduce HCL and peroxide or Cl it blows up (not literally) into a green nasty solution with cemented everything in the sludge.

Please tell if I am crazy but is this AP process here not the best way to go? Not slamming anyone or trying to be rude.....its frustrating. I have a good chem background but I believe I am not good enough as some on here to use the AP process. Just looking for validation.

Thanks all and gold be with you.

Nitric costs a lot more, and is harder for people to find in some areas.


Jim

Jim,

But it is the best way to go correct? Or at least the most likely not foul the reaction? I understand it is a bit more costly but it seems to be dog gone effective.

I believe Hoke recommends this as the first step to cleaning dirty scrap.

Thanks, Robert

The first step should be to remove as many base metals as you can, without the precious metals going into solution with the base metals. Nitric will put palladium and silver with your base metals. It depends on what you are working with I suppose.

Jim