searcher1x
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Lou said:
Lou, not sure what to say. You certainly threw a bunch of stuff at me that I had never heard before! Guess I have more research to do then I realized. Thanks!
Pins, Pins, Pins, What Am I Missing?
- Thread starter searcher1x
- Start date
Help Support Gold Refining Forum:
Lou, not sure what to say. You certainly threw a bunch of stuff at me that I had never heard before! Guess I have more research to do then I realized. Thanks!
Geo
Well-known member
Unless the piece is large or bulky, the stripping cell is a slow go and you must be with it continuously. Since hydrochloric acid is the cheapest component for me, I process all of my loose pins in AP. If the pins are bronze, it does create some tin oxide that can be a pain if you are not accustom to it. The iron based pins do not hinder the dissolution just being iron based. It is a matter of aesthetics to me. Copper(II) chloride will dissolve almost all base metal that is more reactive than gold. Free oxygen is needed to drive the reaction. If left undisturbed, the oxygen is absorbed directly from the air which is very slow. Adding an oxygen source will keep the solution oxygenated and drive the reaction. AP (copper(II) chloride is a set it and forget it type of process. I am finishing a batch of 28 pounds of whole memory sticks in AP. Not recommended for the beginner. I also use an oxygen concentrator so the dissolution of the base metal freeing the foils and chips takes only a few days.
searcher1x
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Barren Realms 007 said:
Thanks for that link. I'm the type of person that once I decide too learn something new I read and research everything I can get my hands on. I only wish I had recognized this forum for the valuable resource it is sooner than I did.
Barren Realms 007 said:
Great Tip! I will do just that!
Barren Realms 007 said:
Thanks for those links, you saved me a lot of time. I like the crock pot idea, beats the heck out of what I'm using now: hot plate, coffee pots and an assortment of bottles and glass ware. I can see that the bottles are dangerous. I've lost 2 in 3 days, they just don't stand up to hot H2SO4. Sooner or later I'm going to either loose a run of gold or end up injured because one of them busts and hot H2SO4 goes everywhere. That's not something I find appealing!
Right now I'm working outside to as a precaution. Several years back I built the wife a green house, went all out with heaters for the winter and fluorescent fixtures in case she wanted grow lights for nights or cloudy days. The first few years she loved it, even had some tomato plants the were close to 2 years old and produced tomato's non-stop the entire 2 years. But as seems to be the case with most things in life, after a few years the thrill wore off and now it sees very little usage.
Been thinking about building a fume hood and working in there through the winter. My background is HVAC, plumbing & controls and I already have all of the necessary parts (fans, plastics for the enclosure and exhaust duct). I know the fumes will work on the fan and eventually render it useless. To compensate for the fumes and extend the life of the fan I was figuring to install a wet filter system to somewhat scrub the fumes before they made it too the fan. I know it will not save the fan but it should extend its life for a few months, maybe even longer.
Any thoughts or suggestions?
maynman1751
Well-known member
What materials are the greenhouse built from? If it's a metal frame, especially aluminum, the fumes from the acids will attack the metal. Even fluorescent light fixtures will be destroyed. Fume control is very important. Ask me how I know!!!! :shock: :roll:
searcher1x
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maynman1751 said:What materials are the greenhouse built from? If it's a metal frame, especially aluminum, the fumes from the acids will attack the metal. Even fluorescent light fixtures will be destroyed. Fume control is very important. Ask me how I know!!!! :shock: :roll:
No metal, basically it's a stick frame with clear Corrugated Polycarbonate panels for the roof and side wall exterior covering, The first 4' from the ground up have a wood panelling on the inside & outside with 4" of insulation. From that point up its Corrugated Polycarbonate on a hinged frame that flip out during really hot months for circulation. Also there's a fan to force circulation when needed. Gets maximum amount of sunshine both summer & winter.
Only thing I did not install was running water, that would have involved trenching and tapping supply in house and extending a line to the structure. Currently we have a lot of 1 gal bottles that we hose fill and store in it. Electricity was no problem, I have a work shop and couple of other buildings very close by so I tapped into their breaker box and pulled a separate circuit for the greenhouse. I really wish I had installed running water now, but it is what it is.
Thanks for your input, I had not considered how the fumes would affect the lights. I'll make sure to include a front panel that slides up and down so I can isolate the hood when I'm not standing in front of it working. That should help contain fumes to some degree.
Any other thoughts, comments or suggestions are welcome.
searcher1x
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maynman1751 said:If it's a metal frame, especially aluminum, the fumes from the acids will attack the metal. Even fluorescent light fixtures will be destroyed. Fume control is very important. Ask me how I know!!!! :shock: :roll:
Maynam1751, I was thinking about the lights and fume control. As long as I keep a negative pressure in the hood and a positive pressure in the greenhouse, fumes shouldn't be a problem. Only way they could possible back into the greenhouse is if the pressure in the hood was equal too or more than the greenhouse, like if the hood fan is turned off. A strong wind outside could force a pressure fluctuation in the hood and back the fumes up but I can control that with a backdraft damper Thanks for mentioning that possibility, if you hadn't got me thinking along that line I would probable not have included a backdraft damper.
searcher1x
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Barren Realms 007 said:
Barren, I was rereading this and it finally sunk in what you said. Correct me if I'm wrong, but I was noticing how some, actually a lot of the pins almost looked like they were a color similar to gold after spending weeks in the solution, which didn't make sense to me. Was this what you were talking about when you said "if you have kovar pins in your mix because the copper will cement out of solution onto your kovar pins"?
It's obvious I picked the worst possible material I could pick for my first attempt at reclaiming. The amount of work and chemicals I have wasted is crazy! And what do I have too show for it, a pot full dirty pins and wore out AP, oopps, I mean copper chloride solution
from all of the magnetic metal in it. The problem is now I'm so pissed :evil: off at the darn pins that I'm more determined than ever to finish them regardless how long it takes or how much it costs! Oh yeah, I got the bubbler running and it does appear to be helping but I'll tell you more once I pull the pins and take a look.Raven turmoil
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i would like to make 1 suggestion, take a small amount of hcl mix with some 95%tin solder, keep in a small bottle. kinda like a test type solution, use it religiously, you can find out more by reading Hoke or the Forum, Hind site is 20/20.
searcher1x,
Your posts are so wordy I am having a hard time following them ( I probably get tired of reading to find your points).
Many members may say the same of my posts.
Reading the forum and study is how to find answers to your questions.
Copper II chloride CuCl2 will dissolve copper.
HCl acid will not attack copper.
HCl will dissolve copper oxide.
So we need to form copper oxide or oxidize the copper.
Oxidize means to loose electrons, the copper metal here gives up electrons, in doing so becomes copper ions, in this case of copper oxide.
We need oxygen to form copper oxide, copper metal being one of the more unreactive metals does not oxidize easily in air, but will easily oxidize if air or oxygen is in the acid.
We can use H2O2 in the acid to start the process, and bubble in air to continue the process.
CuO + 2HCl --> CuCl2 + H2O
We have to get the copper to oxidize, or form CuO.
the reaction of the HCl and copper oxide gives us copper II chloride and water.
The hydrochloric acid acid is reduced to chloride Ions (water forms from the hydrogen of the acid and the oxygen from the copper oxide).
Reduced means to gain electrons.
Now we have a dissolved salt of copper cations and chloride anions.
CuCl2 will dissolve copper.
Or stated another way, will oxidize copper, the copper is oxidized the copper II chloride is reduced in the reaction:
CuCl2 + Cu --> 2CuCl
The copper dissolved by the copper II chloride, the copper is oxidized (gave up electrons to form copper ions) the copper II chloride is reduced (gained electrons to form copper I chloride).
Now we have a solution of copper I chloride.
Copper I chloride will not dissolve copper.
CuCl + Cu --> no reaction
But we can rejuvenate the copper I chloride to form copper II chloride (which will dissolve more copper).
CuCl + HCl --> CuCl2 + H2
So starting with copper metal, hydrochloric acid, and hydrogen peroxide to get some copper II chloride:
Cu + 2HCl + H2O2 --> CuO + 2HCl + H2O (then) --> CuCl2 + 2H2O
Air bubbled in and small additions of HCl (when needed) will keep this reaction going to dissolve copper metal into solution.
One metal (more reactive) will cement or displace a metal from solution which is lower in the "reactivity series of metals" (study this), iron is more reactive than copper, so iron metal will displace copper from solution, in this reaction the iron is oxidized the copper is reduced, the iron gives up electrons to the copper ions, the copper ions gaining electrons are reduced to copper atoms, these copper atoms join to form a copper powder that plates out and or falls to the bottom of the reaction vessel, the iron atoms loosing electrons form iron ions in this case we form a salt of iron chloride.
CuCl2 + Fe --> FeCl2
OH now we do not have copper chloride we now have an iron chloride, Iron I chloride (ferrous chloride), will not dissolve more copper.
Bummer
Not all is lost, with chemistry and an education of it, we can proceed to use this solution to dissolve more iron and even to dissolve more copper, we just need to make the ferrous chloride into ferric chloride (another etch for copper) ferric chloride (FeCl3) will oxidize copper or iron.
Studying the forum you will find this tidbit of information, from one of my previous posts:
Reusing old copper chloride solution to attack copper or Iron chloride solution to dissolve copper, this will work for gold or silver, the silver will form chloride so some of the silver makes silver chloride, some of the thicker pieces of silver are left protected by the chloride crust.
With any recovery methods the more of the base metal you can remove mechanically (like cutting the silver contacts off of the large copper bus bar), the less base metal you will have to dissolve.
Collection of some older posts I made on this subject:
Old used Copper II chloride solution (reusing the waste), or making and using the ferric chloride leach...
Ferrous chloride FeCl2 can be made dissolving Iron in HCl and water approximate equal volumes of water and acid, (steel wool or transformer laminates).
Fe (s) + 2HCl (aq) + H2O (l) --> FeCl2 (aq) + H2 (g)
Ferrous chloride FeCl2 with excess HCl will oxidize with air to form Ferric chloride, but the reaction can take a very long time.
FeCl2 (aq) + 1/4 O2 (g) + HCl (aq) --> FeCl3 (aq) + 1/2 H2O
Now from the ferrous chloride FeCl2, we can make ferric chloride FeCl3, with about equal volume of 3% Hydrogen peroxide H2O2. Heat is generated in the reaction of oxidation of the iron chloride.
FeCl2 (aq) + H2O2 (aq) + HCl (aq) --> FeCl3 + H2O + H + O
Ferric chloride (FeCl3) can etch copper (Cu) or iron (Fe), oxidizing the copper or iron into solution and reducing the ferric chloride (FeCl3) back to ferrous chloride (FeCl2).
2FeCl3 (aq) + Fe (s) --> 3FeCl2 (aq)
Etching copper a two step process.
FeCl3 (aq) + Cu (s) --> FeCl2 (aq) + CuCl
Then
FeCl3 (aq) + CuCl --> FeCl2 (aq) + CuCl2 (aq)
Now we have discussed the normal leach for copper used to etch copper.
Let add some things to this discussions where we can continue to use this solution.
(This discussion also applies to the old used copper II chloride leach we can no longer use because it has been contaminated with iron or Kovar.)
We can heat this solution (ferrous chloride and cupric chloride (FeCl2 + CuCl2) with more copper, (this copper could be copper we need to dissolve from other metals like silver or gold plating like pins or pieces of copper with silver contact points...), the solution when heated being still acidic eats at the copper with a vengeance, especially as it gets concentrated, heating it to a fairly thick dark brown solution.
FeCl2 + CuCl2 + Cu (s) --> FeCl2 (aq) + 2 CuCl (aq)
Here we have both ferrous chloride and cuprous chloride dissolved in solution.
This leaves us with ferrous chloride and cuprous chloride in solution, If we decant a portion of this solution into a jar and let it cool, Most of the CuCl will settle out as a dark powder (along with any gold flakes, silver chloride, lead chloride if involve...).
Now once cooled and settled we can we can decant the mostly ferrous chloride back to the main solution (we will discuss it more later).
The copper I chloride (cuprous chloride) (CuCl), can be rinsed with Hot boiling water (this will dissolve some salts of the iron and copper chlorides, and lead (this rinse water decanted hot can also be returned to the main solution.
This leaves us with white powders of copper I chloride, silver chloride and gold flakes, now we can save these powders for reuse later.
Or dissolve the CuCl in HCl.
CuCl + HCl --> CuCl2 + H
So now after we let the silver chloride and gold foils settle, we can decant the CuCl2 solution, Which is clean enough to use as a new batch of copper II chloride leach (CuCl2) (miss-named acid peroxide leach, or AP on the forum).
Now back to or FeCl2 ferrous chloride solution if you reread this post from the beginning you can see where the ferrous chloride solution (FeCl2) can be oxidized back to the ferric chloride FeCl3 to leach more copper or iron...
____
Now we can get some other iron products, or byproducts, from these iron solutions with the methods above, iron solutions can hydrolyze and with oxygen can form some insoluble iron oxides or hydroxides in solution, or precipitate from solution. Strong heat can accelerate this. One of these can be a red Iron powder (red rouge powder) (a form of rust), that will not dissolve in acids (even aqua regia)...
4 FeCl2 + 4 H2O + O2 <-- --> 2 Fe2O3 + HCl
Or
heated too strongly
FeCl2 +H2O +1/4 O2 --> 1/2 FeCl2 + 2HCl
6 HCl + Fe2O3 + Fe --> 3 FeCl3 + 3H2O
6 FeCl2 +3/2 O2 + H2O --> 2 FeO.OH + 12 HCl
Then
4 FeCl3 + 8H2O --> FeO.OH +12 HCl
FeCl3 + 3H2O --> Fe(OH)3 + HCl
These iron oxides or hydroxides normally do not cause a problem with the gold recovery processes, the red iron powders do not dissolve easily and even gold can be dissolved from the red powder...
viewtopic.php?f=37&t=19816&p=203499&hilit=ferric+chloride#p203499
Here is another place you can use that waste solution, you have been waiting to deal with.
You can use the old waste solution, that old jug of copper chloride that has become more of an Iron chloride (from seeing to much iron in its use)
FeCL3 ferric chloride can etch copper in a two-step process:
FeCl3 + Cu --> FeCl2 + CuCl
Then
FeCl3 + CuCl --> CuCl2 + FeCl2
Silver normally will not dissolve in an acidic Chloride solution, as it oxidizes easily and forms a crust of silver chloride AgCl, which coats the silver protecting it from further oxidation.
But we can put some silver into a solution if we have a very High chloride content:
Silver chloride AgCl is fairly insoluble in water but if we heated it strongly in salt water NaCl (concentrating the solution) we can put some of the silver into the salt solution as silver dichloride soluble in the concentrated brine solution, upon dilution we would again get the insoluble white silver chloride {AgCl2 + H2O --> AgCl + Cl- + H2O} this is the similar to how we get a little silver in our aqua regia solutions.
AgCl + Cl- --> AgCl2
Ferric chloride heated with silver will etch the silver, this iron III chloride solution is aggressive when heated and concentrated, it etches silver plate slowly but effectively, and with plated silver it become very aggressive to the copper under the silver, the concentrated ferric chloride will hold some silver as AgCl2 and precipitate the rest as AgCl, it will also hold a lot of copper into solution as CuCl2 and CuCl, by dilution we can precipitate the CuCl and the little AgCl.
Ag + FeCl3 --> AgCl + FeCl2
Thin plated silver converts to silver chloride fairly easily, thicker pieces of silver can become coated with a protective crust of silver chloride, with this used Iron/ copper chloride solution being heated and concentrated strongly with agitation the silver crust on the silver can become broken loose by the mechanical agitation of the solution (process of the heat and stirring), this can expose fresh silver as the crust is removed converting more silver to AgCl as the fresh silver is exposed, in this many the thicker silver can be converted to silver chloride fairly effectively is one wishes to, it just takes a little longer in the process.
The CuCl white powders can be stored wet, and re acidified in HCl to make an etching solution of copper II Chloride later, leaving the little bit of silver as white powder
4CuCl + 4HCl + O2 --> 4CuCl2 + 2H2O
For the little bit of silver on buss bars or contact arms (silver contact removed) you can dissolve the silver with copper, the heavy bar will still have a lot of copper metal left you could sell as copper metal (you will dissolve a good portion of the copper weight though), for thin silver plate it will dissolve all of the copper.
Ferric chloride will also dissolve iron into solution if needed.
Do not expect to get much silver from buss bars, or from plated silver.
When your done with your waste solution, treat it and dispose of it properly, for those who have not studied how see dealing with waste in our safety section
viewtopic.php?f=60&t=11890&hilit=ferric+chloride
Kovar, An iron compound with about 54% Fe, 29% nickel, 17% cobalt, and traces of silicone, carbon, and manganese, usually used where they need strength or a springy metal.
Beryllium copper is another alloy used, where they need a spring metal or where strength or stress may prove a problem for the softer copper metal, where non sparking may be needed, or a non ferrous metal is needed, beryllium copper can have about 0.5% to 3% beryllium, and many time cobalt and nickel are part of the alloy.
Kovar with all of that iron is much more magnetic than beryllium copper, or the copper pins with a tiny bit of the weakly magnetic nickel plating under the layer of gold.
A strong magnet may attract the nickel, where a weaker magnet would not, and where the weaker magnet would only attract the iron in the Kovar.
If the copper is hard and springy, I would suspect beryllium, pure copper is fairly soft (will cut easy with a knife), and bends easily
In electronic scrap you will find these metals used where they are needed to better perform a function, or are needed to insure reliability, pins that may bend easy may use the stronger Kovar, contact may use beryllium to insure good contact, or for its springy nature, or to strengthen the pins from being bent out of shape by plugging in or unplugging connections…
This is a hard subject to explain but I will try.
Reuse of old copper II chloride leach that has become loaded with iron, and can actually become an iron chloride or and iron/copper chloride solution.
First lets look at what happens when we use our (AP) copper II chloride to dissolve Iron, we convert the copper II chloride CuCl2 (cupric chloride), to FeCl2 (ferrous chloride) and copper metal powders.
CuCl2 + Fe --> FeCl2 +Cu
Our solution during this reaction may actually have several copper and iron chloride salts involved before the above reaction is driven to completion.
Now once we end up with iron II Chloride FeCl2 (ferrous chloride) we normally think of our (AP) or copper II chloride as spent or waste, because FeCl2 is just about useless to attack copper.
But we can use this old spent leach solution to dissolve base metals, and actually we can reuse it to dissolve a heck of a lot more copper (not as FeCl2 but we can get FeCl3 from this solution).
Lets look at some iron chemistry to set up this discussion.
If we dissolve Iron (Fe) in HCl we can make ferrous chloride.
Fe + 2HCl --> FeCl2 + H2
This FeCl2 ferrous chloride will not readily attack copper.
But if let the acidic FeCl2 (ferrous chloride) set exposed in air for a long period of time it will absorb oxygen and oxidize to ferric chloride FeCL3.
4FeCl2 + O2 + HCl --> 4FeCl3 + 2H2O
we can speed this oxidation of ferrous chloride (FeCl2) to FeCl3 (ferric chloride) by adding about equal volumes of 3% H2O2 solution.
2FeCl2 + H2O2 (3%) + 2HCl --> 2FeCl3 + 2H2O
I have also found just strongly heating the solution also help it to absorb oxygen especially when the solution is concentrated.
Now Ferric chloride FeCl3 is a great etch for copper metals, hot concentrated solutions heated to a thicker solution, help to convert silver to silver chloride the heavy brine solution helps to remove the silver chloride crust that forms, gold is not attacked but plated gold will flake off as copper underneath is attacked.
Ferric chloride is used to etch copper circuit boards, just the same way the copper II chloride leach we call acid peroxide is used, the main reason to use CuCl2 cupric chloride leach over the ferric chloride leach to dissolve copper is the ease of which we can rejuvenate the cupric leach for reuse, in a copper cycle.
we can also rejuvenate the Iron chloride leach, but it is not as easy to get the copper back out of the leach.
I have stumbled on a way to use the ferric chloride leach (our old spent copper chloride leaches), by reusing my waste solution to dissolve base metals.
And actually make a copper II chloride leach from the copper I chloride powders in the process.
First we need to look at the two-step process of using ferric chloride FeCl3 to etch copper.
FeCl3 + Cu --> FeCl2 + CuCl
then
FeCl3 + CuCl --> FeCl2 + CuCl2
notice in the first part of reaction we can form CuCl, and later in the reaction the CuCl is oxidized to CuCl2, as the FeCl3 is reduced to FeCl2.
And in the second part of the reaction we end up with both iron and copper chlorides in solution as FeCl2 and CuCl2.
If we stop this above reaction in the middle we can separate most of the CuCl and let the concentrated solution cool and settle to powders of CuCl, AgCl and Au foils.
Returning most of the FeCl2 to the main reaction to help dissolve more copper as it picks up air (or we can add a little H2O2 to convert the FeCl2 back to FeCl3...
This is what I tried to explain in the post above.
Where I said:
I reuse this solution to dissolve copper and base metals.
Actually it become more of an iron chloride, if strongly heated you will be amazed at how much copper you can dissolve with this old used (AP leach), the iron chloride will dissolve pounds of copper in a corning dish on a hot plate when the solution get thick brown, decant a portion of the leach into a cooling jar there most of the copper will settle out as copper I chloride (a brown powder, unless diluted with water which will turn it white as acids are diluted) after settling you can return iron chloride liquid back to the corning dish to dissolve more copper,
The copper I chloride powder washed with a little water will give a white powder of copper I chloride this rinse liquid you can add back to the heated corning dish above to dissolve more copper.
This leaves you with the white copper I chloride powders, with some HCl add this dissolves and becomes copper II chloride, which can be used, as you know to dissolve copper, and if you had silver or gold on the copper you were dissolving above, you will be left with gold foils or silver chloride powders after adding the HCl.
So here we get our CuCl back to make a new CuCl2 leach solution (acid peroxide leach), we concentrate our old iron chloride solution (to treat for waste) giving us less waste to deal with.
And dissolve pounds of copper from things like contact points with chunks of copper that were cut from the relay or motor contactors, or gold foils from copper brass or iron pins...
Reusing a solution that was once considered a waste solution, to do more work dissolving pounds of copper, collecting a useful copper I chloride we can make into a fresh copper II chloride leach, and collect silver and gold, while reducing the left over waste solution to deal with.
viewtopic.php?f=60&t=19838&hilit=ferric+chloride
Make your post simpler And I may tend to read them more often. instead of just scanning over them.
Your posts are so wordy I am having a hard time following them ( I probably get tired of reading to find your points).
Many members may say the same of my posts.
Reading the forum and study is how to find answers to your questions.
Copper II chloride CuCl2 will dissolve copper.
HCl acid will not attack copper.
HCl will dissolve copper oxide.
So we need to form copper oxide or oxidize the copper.
Oxidize means to loose electrons, the copper metal here gives up electrons, in doing so becomes copper ions, in this case of copper oxide.
We need oxygen to form copper oxide, copper metal being one of the more unreactive metals does not oxidize easily in air, but will easily oxidize if air or oxygen is in the acid.
We can use H2O2 in the acid to start the process, and bubble in air to continue the process.
CuO + 2HCl --> CuCl2 + H2O
We have to get the copper to oxidize, or form CuO.
the reaction of the HCl and copper oxide gives us copper II chloride and water.
The hydrochloric acid acid is reduced to chloride Ions (water forms from the hydrogen of the acid and the oxygen from the copper oxide).
Reduced means to gain electrons.
Now we have a dissolved salt of copper cations and chloride anions.
CuCl2 will dissolve copper.
Or stated another way, will oxidize copper, the copper is oxidized the copper II chloride is reduced in the reaction:
CuCl2 + Cu --> 2CuCl
The copper dissolved by the copper II chloride, the copper is oxidized (gave up electrons to form copper ions) the copper II chloride is reduced (gained electrons to form copper I chloride).
Now we have a solution of copper I chloride.
Copper I chloride will not dissolve copper.
CuCl + Cu --> no reaction
But we can rejuvenate the copper I chloride to form copper II chloride (which will dissolve more copper).
CuCl + HCl --> CuCl2 + H2
So starting with copper metal, hydrochloric acid, and hydrogen peroxide to get some copper II chloride:
Cu + 2HCl + H2O2 --> CuO + 2HCl + H2O (then) --> CuCl2 + 2H2O
Air bubbled in and small additions of HCl (when needed) will keep this reaction going to dissolve copper metal into solution.
One metal (more reactive) will cement or displace a metal from solution which is lower in the "reactivity series of metals" (study this), iron is more reactive than copper, so iron metal will displace copper from solution, in this reaction the iron is oxidized the copper is reduced, the iron gives up electrons to the copper ions, the copper ions gaining electrons are reduced to copper atoms, these copper atoms join to form a copper powder that plates out and or falls to the bottom of the reaction vessel, the iron atoms loosing electrons form iron ions in this case we form a salt of iron chloride.
CuCl2 + Fe --> FeCl2
OH now we do not have copper chloride we now have an iron chloride, Iron I chloride (ferrous chloride), will not dissolve more copper.
Bummer
Not all is lost, with chemistry and an education of it, we can proceed to use this solution to dissolve more iron and even to dissolve more copper, we just need to make the ferrous chloride into ferric chloride (another etch for copper) ferric chloride (FeCl3) will oxidize copper or iron.
Studying the forum you will find this tidbit of information, from one of my previous posts:
Reusing old copper chloride solution to attack copper or Iron chloride solution to dissolve copper, this will work for gold or silver, the silver will form chloride so some of the silver makes silver chloride, some of the thicker pieces of silver are left protected by the chloride crust.
With any recovery methods the more of the base metal you can remove mechanically (like cutting the silver contacts off of the large copper bus bar), the less base metal you will have to dissolve.
Collection of some older posts I made on this subject:
Old used Copper II chloride solution (reusing the waste), or making and using the ferric chloride leach...
Ferrous chloride FeCl2 can be made dissolving Iron in HCl and water approximate equal volumes of water and acid, (steel wool or transformer laminates).
Fe (s) + 2HCl (aq) + H2O (l) --> FeCl2 (aq) + H2 (g)
Ferrous chloride FeCl2 with excess HCl will oxidize with air to form Ferric chloride, but the reaction can take a very long time.
FeCl2 (aq) + 1/4 O2 (g) + HCl (aq) --> FeCl3 (aq) + 1/2 H2O
Now from the ferrous chloride FeCl2, we can make ferric chloride FeCl3, with about equal volume of 3% Hydrogen peroxide H2O2. Heat is generated in the reaction of oxidation of the iron chloride.
FeCl2 (aq) + H2O2 (aq) + HCl (aq) --> FeCl3 + H2O + H + O
Ferric chloride (FeCl3) can etch copper (Cu) or iron (Fe), oxidizing the copper or iron into solution and reducing the ferric chloride (FeCl3) back to ferrous chloride (FeCl2).
2FeCl3 (aq) + Fe (s) --> 3FeCl2 (aq)
Etching copper a two step process.
FeCl3 (aq) + Cu (s) --> FeCl2 (aq) + CuCl
Then
FeCl3 (aq) + CuCl --> FeCl2 (aq) + CuCl2 (aq)
Now we have discussed the normal leach for copper used to etch copper.
Let add some things to this discussions where we can continue to use this solution.
(This discussion also applies to the old used copper II chloride leach we can no longer use because it has been contaminated with iron or Kovar.)
We can heat this solution (ferrous chloride and cupric chloride (FeCl2 + CuCl2) with more copper, (this copper could be copper we need to dissolve from other metals like silver or gold plating like pins or pieces of copper with silver contact points...), the solution when heated being still acidic eats at the copper with a vengeance, especially as it gets concentrated, heating it to a fairly thick dark brown solution.
FeCl2 + CuCl2 + Cu (s) --> FeCl2 (aq) + 2 CuCl (aq)
Here we have both ferrous chloride and cuprous chloride dissolved in solution.
This leaves us with ferrous chloride and cuprous chloride in solution, If we decant a portion of this solution into a jar and let it cool, Most of the CuCl will settle out as a dark powder (along with any gold flakes, silver chloride, lead chloride if involve...).
Now once cooled and settled we can we can decant the mostly ferrous chloride back to the main solution (we will discuss it more later).
The copper I chloride (cuprous chloride) (CuCl), can be rinsed with Hot boiling water (this will dissolve some salts of the iron and copper chlorides, and lead (this rinse water decanted hot can also be returned to the main solution.
This leaves us with white powders of copper I chloride, silver chloride and gold flakes, now we can save these powders for reuse later.
Or dissolve the CuCl in HCl.
CuCl + HCl --> CuCl2 + H
So now after we let the silver chloride and gold foils settle, we can decant the CuCl2 solution, Which is clean enough to use as a new batch of copper II chloride leach (CuCl2) (miss-named acid peroxide leach, or AP on the forum).
Now back to or FeCl2 ferrous chloride solution if you reread this post from the beginning you can see where the ferrous chloride solution (FeCl2) can be oxidized back to the ferric chloride FeCl3 to leach more copper or iron...
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Now we can get some other iron products, or byproducts, from these iron solutions with the methods above, iron solutions can hydrolyze and with oxygen can form some insoluble iron oxides or hydroxides in solution, or precipitate from solution. Strong heat can accelerate this. One of these can be a red Iron powder (red rouge powder) (a form of rust), that will not dissolve in acids (even aqua regia)...
4 FeCl2 + 4 H2O + O2 <-- --> 2 Fe2O3 + HCl
Or
heated too strongly
FeCl2 +H2O +1/4 O2 --> 1/2 FeCl2 + 2HCl
6 HCl + Fe2O3 + Fe --> 3 FeCl3 + 3H2O
6 FeCl2 +3/2 O2 + H2O --> 2 FeO.OH + 12 HCl
Then
4 FeCl3 + 8H2O --> FeO.OH +12 HCl
FeCl3 + 3H2O --> Fe(OH)3 + HCl
These iron oxides or hydroxides normally do not cause a problem with the gold recovery processes, the red iron powders do not dissolve easily and even gold can be dissolved from the red powder...
viewtopic.php?f=37&t=19816&p=203499&hilit=ferric+chloride#p203499
Here is another place you can use that waste solution, you have been waiting to deal with.
You can use the old waste solution, that old jug of copper chloride that has become more of an Iron chloride (from seeing to much iron in its use)
FeCL3 ferric chloride can etch copper in a two-step process:
FeCl3 + Cu --> FeCl2 + CuCl
Then
FeCl3 + CuCl --> CuCl2 + FeCl2
Silver normally will not dissolve in an acidic Chloride solution, as it oxidizes easily and forms a crust of silver chloride AgCl, which coats the silver protecting it from further oxidation.
But we can put some silver into a solution if we have a very High chloride content:
Silver chloride AgCl is fairly insoluble in water but if we heated it strongly in salt water NaCl (concentrating the solution) we can put some of the silver into the salt solution as silver dichloride soluble in the concentrated brine solution, upon dilution we would again get the insoluble white silver chloride {AgCl2 + H2O --> AgCl + Cl- + H2O} this is the similar to how we get a little silver in our aqua regia solutions.
AgCl + Cl- --> AgCl2
Ferric chloride heated with silver will etch the silver, this iron III chloride solution is aggressive when heated and concentrated, it etches silver plate slowly but effectively, and with plated silver it become very aggressive to the copper under the silver, the concentrated ferric chloride will hold some silver as AgCl2 and precipitate the rest as AgCl, it will also hold a lot of copper into solution as CuCl2 and CuCl, by dilution we can precipitate the CuCl and the little AgCl.
Ag + FeCl3 --> AgCl + FeCl2
Thin plated silver converts to silver chloride fairly easily, thicker pieces of silver can become coated with a protective crust of silver chloride, with this used Iron/ copper chloride solution being heated and concentrated strongly with agitation the silver crust on the silver can become broken loose by the mechanical agitation of the solution (process of the heat and stirring), this can expose fresh silver as the crust is removed converting more silver to AgCl as the fresh silver is exposed, in this many the thicker silver can be converted to silver chloride fairly effectively is one wishes to, it just takes a little longer in the process.
The CuCl white powders can be stored wet, and re acidified in HCl to make an etching solution of copper II Chloride later, leaving the little bit of silver as white powder
4CuCl + 4HCl + O2 --> 4CuCl2 + 2H2O
For the little bit of silver on buss bars or contact arms (silver contact removed) you can dissolve the silver with copper, the heavy bar will still have a lot of copper metal left you could sell as copper metal (you will dissolve a good portion of the copper weight though), for thin silver plate it will dissolve all of the copper.
Ferric chloride will also dissolve iron into solution if needed.
Do not expect to get much silver from buss bars, or from plated silver.
When your done with your waste solution, treat it and dispose of it properly, for those who have not studied how see dealing with waste in our safety section
viewtopic.php?f=60&t=11890&hilit=ferric+chloride
Kovar, An iron compound with about 54% Fe, 29% nickel, 17% cobalt, and traces of silicone, carbon, and manganese, usually used where they need strength or a springy metal.
Beryllium copper is another alloy used, where they need a spring metal or where strength or stress may prove a problem for the softer copper metal, where non sparking may be needed, or a non ferrous metal is needed, beryllium copper can have about 0.5% to 3% beryllium, and many time cobalt and nickel are part of the alloy.
Kovar with all of that iron is much more magnetic than beryllium copper, or the copper pins with a tiny bit of the weakly magnetic nickel plating under the layer of gold.
A strong magnet may attract the nickel, where a weaker magnet would not, and where the weaker magnet would only attract the iron in the Kovar.
If the copper is hard and springy, I would suspect beryllium, pure copper is fairly soft (will cut easy with a knife), and bends easily
In electronic scrap you will find these metals used where they are needed to better perform a function, or are needed to insure reliability, pins that may bend easy may use the stronger Kovar, contact may use beryllium to insure good contact, or for its springy nature, or to strengthen the pins from being bent out of shape by plugging in or unplugging connections…
This is a hard subject to explain but I will try.
Reuse of old copper II chloride leach that has become loaded with iron, and can actually become an iron chloride or and iron/copper chloride solution.
First lets look at what happens when we use our (AP) copper II chloride to dissolve Iron, we convert the copper II chloride CuCl2 (cupric chloride), to FeCl2 (ferrous chloride) and copper metal powders.
CuCl2 + Fe --> FeCl2 +Cu
Our solution during this reaction may actually have several copper and iron chloride salts involved before the above reaction is driven to completion.
Now once we end up with iron II Chloride FeCl2 (ferrous chloride) we normally think of our (AP) or copper II chloride as spent or waste, because FeCl2 is just about useless to attack copper.
But we can use this old spent leach solution to dissolve base metals, and actually we can reuse it to dissolve a heck of a lot more copper (not as FeCl2 but we can get FeCl3 from this solution).
Lets look at some iron chemistry to set up this discussion.
If we dissolve Iron (Fe) in HCl we can make ferrous chloride.
Fe + 2HCl --> FeCl2 + H2
This FeCl2 ferrous chloride will not readily attack copper.
But if let the acidic FeCl2 (ferrous chloride) set exposed in air for a long period of time it will absorb oxygen and oxidize to ferric chloride FeCL3.
4FeCl2 + O2 + HCl --> 4FeCl3 + 2H2O
we can speed this oxidation of ferrous chloride (FeCl2) to FeCl3 (ferric chloride) by adding about equal volumes of 3% H2O2 solution.
2FeCl2 + H2O2 (3%) + 2HCl --> 2FeCl3 + 2H2O
I have also found just strongly heating the solution also help it to absorb oxygen especially when the solution is concentrated.
Now Ferric chloride FeCl3 is a great etch for copper metals, hot concentrated solutions heated to a thicker solution, help to convert silver to silver chloride the heavy brine solution helps to remove the silver chloride crust that forms, gold is not attacked but plated gold will flake off as copper underneath is attacked.
Ferric chloride is used to etch copper circuit boards, just the same way the copper II chloride leach we call acid peroxide is used, the main reason to use CuCl2 cupric chloride leach over the ferric chloride leach to dissolve copper is the ease of which we can rejuvenate the cupric leach for reuse, in a copper cycle.
we can also rejuvenate the Iron chloride leach, but it is not as easy to get the copper back out of the leach.
I have stumbled on a way to use the ferric chloride leach (our old spent copper chloride leaches), by reusing my waste solution to dissolve base metals.
And actually make a copper II chloride leach from the copper I chloride powders in the process.
First we need to look at the two-step process of using ferric chloride FeCl3 to etch copper.
FeCl3 + Cu --> FeCl2 + CuCl
then
FeCl3 + CuCl --> FeCl2 + CuCl2
notice in the first part of reaction we can form CuCl, and later in the reaction the CuCl is oxidized to CuCl2, as the FeCl3 is reduced to FeCl2.
And in the second part of the reaction we end up with both iron and copper chlorides in solution as FeCl2 and CuCl2.
If we stop this above reaction in the middle we can separate most of the CuCl and let the concentrated solution cool and settle to powders of CuCl, AgCl and Au foils.
Returning most of the FeCl2 to the main reaction to help dissolve more copper as it picks up air (or we can add a little H2O2 to convert the FeCl2 back to FeCl3...
This is what I tried to explain in the post above.
Where I said:
I reuse this solution to dissolve copper and base metals.
Actually it become more of an iron chloride, if strongly heated you will be amazed at how much copper you can dissolve with this old used (AP leach), the iron chloride will dissolve pounds of copper in a corning dish on a hot plate when the solution get thick brown, decant a portion of the leach into a cooling jar there most of the copper will settle out as copper I chloride (a brown powder, unless diluted with water which will turn it white as acids are diluted) after settling you can return iron chloride liquid back to the corning dish to dissolve more copper,
The copper I chloride powder washed with a little water will give a white powder of copper I chloride this rinse liquid you can add back to the heated corning dish above to dissolve more copper.
This leaves you with the white copper I chloride powders, with some HCl add this dissolves and becomes copper II chloride, which can be used, as you know to dissolve copper, and if you had silver or gold on the copper you were dissolving above, you will be left with gold foils or silver chloride powders after adding the HCl.
So here we get our CuCl back to make a new CuCl2 leach solution (acid peroxide leach), we concentrate our old iron chloride solution (to treat for waste) giving us less waste to deal with.
And dissolve pounds of copper from things like contact points with chunks of copper that were cut from the relay or motor contactors, or gold foils from copper brass or iron pins...
Reusing a solution that was once considered a waste solution, to do more work dissolving pounds of copper, collecting a useful copper I chloride we can make into a fresh copper II chloride leach, and collect silver and gold, while reducing the left over waste solution to deal with.
viewtopic.php?f=60&t=19838&hilit=ferric+chloride
Make your post simpler And I may tend to read them more often. instead of just scanning over them.
