Recycle your used Acid Peroxide.

[lysdexic]

Thank you GSP, then I am on the right path with the different forms of CuCl (CuCl and CuCl₂) and the number of electrons gained or lost.

The oxygen, a powerful oxidizer, oxidizes the Cu⁺¹ ion to Cu⁺². The Cl ion in both cases is Cl^-1. Therefore, to be in balance, they would be CuCl and CuCl₂, respectively.

In other words, it would take one Cl^-1 to combine with one Cu⁺¹, but two Cl^-1 to combine with one Cu⁺². The total electrical charge in each case must equal zero.

Does that mean that the oxygen that reacts with the CuCl (entering the solution) as it' is bubbled through the solution accepts an electron from a Cu⁺¹ creating a Cu⁺² ion and an O^-1? or rather it accepts one electron from each of 2 Cu⁺¹ making it O^-2...
2HCl + 2CuCl + O --> 2CuCl₂ + H₂O
which balances the equation
I think part of what I am missing is 2H⁺¹ + O^-2 --> H₂O I have H₂O stuck in my head as a polar covalent bond and I guess I'm missing a bunch of the "ions and bonding information", so maybe I can focus on looking into that and see if "the light goes on".

GSP, I do appreciate you taking the time to help me with all of my random questions. I do understand the value of a person's time and I am very grateful you consider my questions worthy of your time.

 

[goldsilverpro]

https://en.wikipedia.org/wiki/Redox

 

[lysdexic]

Thank you again GSP. It looks like there is a (again) a lot more reading to do. Each answer brings questions which bring answers which... Right now I have tabs open on a number of things that the wiki page on Redox led to (Redox rang a bell but there wasn't a light that went on until your nudge). The first thing that jumped out at me was:

"Though sufficient for many purposes, these descriptions are not precisely correct. Oxidation and reduction properly refer to a change in oxidation state — the actual transfer of electrons may never occur. Thus, oxidation is better defined as an increase in oxidation state, and reduction as a decrease in oxidation state. In practice, the transfer of electrons will always cause a change in oxidation state, but there are many reactions that are classed as "redox" even though no electron transfer occurs (such as those involving covalent bonds)."

To be honest the thought of H being an ion made me feel a bit queasy. Another area I opened to start learning is electrochemistry. I wouldn't call it a hypothesis, but I'm thinking the the product of using an inert anode and reducing Cu from a CuCl solution is going to yield Cu and Cl (in simplistic theoretical terms). After a bit of study there's plenty here to read.

Again, thank you!

Doug

 

[lysdexic]

I am a NOOB! I am NOT a chemist or experienced refiner. What I'm writing is purely speculation in my attempt at understanding this process. There is plenty of factual information on this site... search for it! If you want to follow along and see if someone "grades my homework" fine, maybe we'll learn something. My "homework" however is not to be taken as fact.

Okay... after some further reading I'm thinking Firewalker's Fe electrodes (at least partially) produced a single displacement reaction.
ClCu_x + Fe = FeCl_x + Cu
If the reaction was run to completion it would be a FeCl solution (in the real world nothing is ever as pure as it is on paper) and if the reaction was only partial it would be a contaminated FeCl or CuCl solution (how far the reaction is carried out would determine which one was predominant).

Lazersteve in his experiment with a closed loop CuCl etching/electro rejuvenation tried a saturated CuCl solution and evolved enough Cl gas that he shut the reaction down. I've also read (off site I believe) that Cl gas (edit: removed faulty subscript) is somewhat soluble. I've read that in electrowinng (in this case copper from CuCl solution) the reaction (not sure of the correct term) intensity(?) is determined (in part anyway) by concentration and currant flow through the solution.

My theoretical conclusion is that should I pursue reclaiming of Cu from escrap that using Firewalker's process mentioned here, Cu could be recovered from solution in a more solid state (verses simply dropping as a powder with iron) which would reduce the tendency for the Cu to be oxidized/vaporized when being melted. This could be done with spent solutions as a Cu recovery/waste treatment step but not to rejuvenate CuCl solutions. Electrowinning Cu could possibly rejuvenate CuCl to a degree but fresh HCl would still be required (with oxygen from H₂O₂ or bubbled air) to keep the CuCl etching solution viable. The electrolyte from electrowinning could be recycled along with "fresher" CuCl leach (solution that was retired from recovering gold) and used to recover Cu from valueless circuit boards.

I'm not looking for a way to get rich. I'm just looking for a complete as possible method of recycling escrap as a hobby. I want the shiny gold and the silver but I want as little waste as possible and as many useful by products as possible. Copper is probably the most plentiful metal component of escrap and therefore the first part of the recovery/waste stream that got my attention (well fumes and hazardous chemicals are actually first along with doing everything safely).

As a useful byproduct of this investigation I have begun to gain an understanding of the chemistry involved in the processes discussed here. It looks like a win no matter where it leads.

Doug

 

[butcher]

Doug, it is always a win, when we educate ourselves.

 

[lysdexic]

Thanks butcher... agreed.

Do you mind me asking if you noticed anything amiss with my conclusions?

Doug

 

[johnny309]

As a matter of fact....I try to get cooper out from AP using electricity and the result were good(minus the fact that the cathode,stainless steel is wearing out ).
The cooper came very pure......but........: you need to dilute your solution of used AP because of ...more concentrated is the solution ,more amps will required .
I have put aside "some" ...gallons....to do some experiments.........because....it is another metal involved......Ni. But...the remaining solution will be combined with H2SO4....and the Sn...is still in the mix(which is an " extra")

 

[butcher]

Doug, it looks like you are learning and are getting the general Idea, there is some mistakes, but that comes with the learning process. you covered such a wide area, it would be hard for me to comment on all of it.

Electrons of the atoms are transfered, or shared, when elements combined to form compounds, they can form several different types of chemical bonds.

Ionic bonds one atom gives up and electron and the other atom takes this electron the electron is tranfered from one atoms outer shell (of the valence electrons) to the other atoms outer shell in the chemical reaction.

In covalent bonds the elecron is shared between the two atoms, there is also double covalent bonds, triple covalent bonds, polar and non polar covalent bonding...

The electrons are lost gained or shared, but it is all about the tranfer of these electrons, energy is consumed or released during these chemical reactions, these give us a way to kind of explain what is happening, and also predict what may happen in the chemical reactions.

As far as electrolysis it is in a way, using an external power source, we can separate these bonds, forcing electron movement where it may not naturally occur, separate anions and cations, force oxidation and reduction...

We can also use the electro chemical reaction (movement of electrons) to move electrons through chains of other atoms, like the reaction of two disimilar metals in an acid or base solution (battery), the electro chemical reaction of electrons moving oxidation and reduction, we can force movement of electrons through a chain of copper atoms (wire), producing energy in this wire (heat or light)...

Here I am jumping all over the place, it is simpler for me to stick to one simple point at a time, I can get lost easily if I start thinking about more than one thing at a time. I think my small brain starts running around in circles in my head.

 

[lysdexic]

Johnny309, It's good to know that electrolysis does work to reclaim Cu. Is the Ni in your solution from the stainless steel anode? I'm just beginning and I already hate Sn. I need it to make testing solution but I'm not going to try and reclaim Tin for that. My plans right now are to use an inert anode (mentioned by flexyman) to reclaim Cu from solutions I plan on reusing and Fe (steel) anode and cathode for solutions that are being retired into the waste stream. I'm not going that route because I think it's the best way, it's just the best way to get the results I'm looking for. Copper simply dropped with Fe is a fine powder that is troublesome to melt. From what I've seen and read copper from electrolysis is in a form better suited for melting. ...thank you.

Butcher, I did chuckle

Here I am jumping all over the place, it is simpler for me to stick to one simple point at a time, I can get lost easily if I start thinking about more than one thing at a time. I think my small brain starts running around in circles in my head.

It seems we have something in common, as you mentioned I kind of covered a wide area. I find everything is connected and when I start looking for one answer it leads to more questions and so on. I started here wanting to know if the HCl was recovered as I've read nitric can be in some cases. A simple no would have got me nowhere. I believe that I'm incapable of linear thought. I kind of envy those you can just read Hoke and follow her directions. I need to be able to understand what's happening when I follow those instructions or I get confused.

As for the small brain comment, with all do respect, that's bull...., the only small brains I've seen here were those who made a few scary posts and then were gone. Probably off to hurt themselves, others and or the environment. It seems to me that being smart isn't some simple measurement, everything is a trade off. I've heard people claim they aren't very smart but their common sense and wisdom leaves me in awe. Everyone has strengths and weaknesses, smart people know this and learn to use it to their advantage. Stupid people think they know more than they do and refuse to listen and learn. ...sorry, /end rant

I do remember some about all the things you mentioned (ions, bonding etc). I took High School level Chemistry (Physics, Electronics and 4 years of math), but that was almost 40 years ago and it's very foggy. I do know and understand that anything you (and all members) give is a gift and I'm extremely grateful. I would prefer to be a contributor rather than a consumer, that's not the case at the moment. All of you owe me nothing, I owe all of you everything... maybe if I work hard I can one day give something back.

Thanks again (to all of you)

Doug

 

[butcher]

As far as recycling or rejuvenating HCl from a copper chloride solution would be very difficult from a simple electrolytic cell setup.

To setup for this discussion I will use some formulas.

Copper being a fairly un-reactive metal, will not dissolve in a non oxidizing acid like HCl, being placed below hydrogen in the reactivity series of metal.

Cu + HCl --> No Reaction.

Copper metal need to be oxidized (an electron removed) to dissolve in HCl, and to form chloride of copper compound dissolved into solution.

Air, oxygen in water, H2O2 hydrogen peroxide or some other oxidizing agent to oxidize the copper to copper oxide, so the copper oxide can react with the HCl to form copper chlorides dissolved in this water solution.

CuO(s) + 2H⁺ -->Cu²⁺(aq) + H₂O(l)
CuO + 2HCl --> CuCl₂ + H₂O
Cu + 2HCl + H₂O₂ --> CuCl₂ + 2H₂O

Notice in the reactions above the hydrogen from the acid, the oxygen from the air, H2O2, or from the oxygen of the copper oxide form water in solution.

2H⁺ + O ^2- --> H₂O (aq)

HCl, hydrochloric acid, hydrogen and chlorine gas in a chemical redox reaction forms the acid.
H₂⁺ + Cl₂^- --> 2HCl

Basically the Hydrogen is what makes an acid an acid, and this hydrogen or acid is used up in the reaction, to make the more stable water (although we can have some excess acid in solution depending on our solutions), the hydrogen that forms the chloride acid (hydrochloric acid, HCl) is used, reacting with oxygen or oxides to form water.

When we dissolve the metals in acid or oxidizers we are transferring electrons, like from copper atoms we oxidize (remove an electron from the copper metal atom), The copper is now an ion (Cation), the oxidizer or acid is reduced (gain of electron) to an ion (anion), in this case the Cation Hydrogen (from the acid) and the anion from the oxide or oxygen form the compound of water, the copper forms an Cation with the anion of chloride (reduced acid HCl) to form the compound of copper chloride in this solution of water, the chloric of the acid being reduced to chlorides with the copper as copper chloride salt dissolved in water.

Now when we use electrolysis we can separate the compounds in solution, the compounds of copper chloride can be separated into the anions and Cations in the cell, the Cu⁺ Cation moves to the cathode compartment, or side of the cell can gain an electron (from our external power source or battery) and plate out as copper metal, this ion being reduced back to metal, as the copper ion gets back the missing electron.
And the chloride anion moves towards the anode where it loses an electron, being oxidized back to elemental chlorine and leaves the solution as gas or can stay in solution (depending on conditions) note it would be harder to keep this solution in the liquid under the conditions most simple cells are run under.

What about the Hydrogen from our original acid that made water? well we can also split this water compound of water in our electrolytic cell , forming hydrogen gas at the anode, and hydroxide at the cathode...
but getting the hydrogen and chlorine gases to form back to HCl acid would not easily work in a simple cell, the conditions these gases form at in the cell may not be under the same conditions of cell operation, capturing of these gases to remake our HCl acid would not be an easy task...

It would take a lot more explanation to give more of an explanation as to why this would not work easily to re-make HCl acid, besides HCl is so common and cheap it would not be worth the trouble, it would be easier to make HCl from sulfuric acid and salt than to try and get it out of copper chloride with electrolysis, at least on a small scale in a homemade electrolytic cell.

Although copper metal is a fairly un-reactive metal, it will oxidize easily with air or oxygen at high heat like when trying to melt it, forming copper oxides which would form a slag of copper oxides, instead of reducing the copper to metal in the melt, for melting copper we need to remove oxygen from the copper and the melting environment, to do this we can use chemistry in our melt, using a reducing flame to heat the environment, use a charcoal fire limiting oxygen in the melt, and or using a carbon source in our flux like flour, charcoal, sugar, sodium carbonate..., to remove oxides or oxygen from the copper and its environment in the chemistry of the melt.

There are other times where we may wish to oxidize the copper in a melt, using an oxygen rich environment or a flux like a nitrate to oxidize the copper into an oxide so it will report into the slag.

Melting metals is a chemical reaction where metals can be oxidized or reduced (again transfer of electrons), (just like other chemical reactions we perform with metals), depending on the metal, and how it reacts with oxygen or other chemicals in the melt, we can change the chemical properties of our melt to get a desired chemical reaction, in the melting environment or with flux or both.

I do not know how well I explained this, or if it will help any with your questions or not.

A few mistake corrected Thanks Dave

 

[lysdexic]

Butcher, you explained very well. Some I already "kind of" understood some I did not and you connected some dots for me. Thank you. I really didn't expect you to take the time to give me a chemistry lesson but I sure do appreciate it.

I have no intentions of making heroic efforts to reform HCl. I'll just accept there is no perpetual motion. If I use electrolysis to reduce Cu to metal, then Cl will also be released from solution. I would end up with Cu (solid) Cl (gas) and Water (Plus whatever CuCl_x that wasn't decomposed). Basically Copper, a dilute CuCl solution and Cl gas is what I'd end up with.

Although copper metal is a fairly un-reactive metal, it will oxidize easily with air or oxygen at high heat like when trying to melt it, forming copper oxides which would form a slag of copper oxides, instead of reducing the copper to metal in the melt, for melting copper we need to remove oxygen from the copper and the melting environment, to do this we can use chemistry in our melt, using a reducing flame to heat the environment, use a charcoal fire limiting oxygen in the melt, and or using a carbon source in our flux like flour, charcoal, sugar, sodium carbonate..., to remove oxides or oxygen from the copper and its environment in the chemistry of the melt.

There are other times where we may wish to oxidize the copper in a melt, using an oxygen rich environment or a flux like a nitrate to oxidize the copper into an oxide so it will report into the slag.

Melting metals is a chemical reaction where metals can be oxidized or reduced (again transfer of electrons), (just like other chemical reactions we perform with metals), depending on the metal, and how it reacts with oxygen or other chemicals in the melt, we can change the chemical properties of our melt to get a desired chemical reaction, in the melting environment or with flux or both.

This caught me totally off guard. I have always seen melting metal as a simple change of state. It should have dawned on me long ago. When iron ore is smelted it is a chemical reaction converting FeO into Fe + O ...wow I can be dense. Fluxing, why, when and what never made sense to me, I just knew it worked, so it should be done. Even here hearing about using nitrates to oxidize an undesirable metal it didn't sink in. Anyway... Copper has a tendency to oxidize whether a larger piece or a fine powder? (I've only melted aluminum and zinc alloy ...well a little silver and long ago lead) I've never melted Copper yet ...well once I read that certain Aluminum/Copper alloys were were so brittle they broke like glass, so I melted a couple ounces of aluminum then added close to the same weight of copper and poured it on some sand when it had all melted. After it cooled I picked up the flat "puddle" and dropped it on the concrete... it shattered like glass (sorry for the side track). The scrap yard people told me heavier copper wire is worth more than fine wire because of loss when melting the finer wire. Is there less loss with solid copper than with powder?

There's about 2 acres of charcoal growing in my back yard, and we heat solely with wood, so charcoal would be my fuel of choice for the more heat demanding melts. A covered crucible and a carbon based flux (charcoal) perhaps?

Still much to learn for me... thanks again

Doug

 

[butcher]

Fine powder reacts easier, more surface area, kind of similar to when we oxidize a metal with acids to dissolve it, the fine powder is much more reactive in the chemical treatment.

 

[johnny309]

Ni in AP is the barrier metal between gold plating and the copper circuit...

 

[lazersteve]

The water soluble starting CuCl2 is dissolved into the fresh solution as it forms. As more copper is dissolved into the solution by the etch the two chlorine atoms are spread across two copper atoms becoming 2CuCl which ultimately saturates the solution as the process repeats and CuCl eventually precipitates as as solid. Adding more HCl dissolves the CuCl as it is soluble in concentrated HCl. If an oxidizer (O2, electrons, etc.) is present, the CuCl2 regenerates and the solution becomes useful again.

The overall reaction is mainly dependent upon the solubility of the active ingredient, CuCl2 and the free HCl in the solution.

1) There should be no sediment forming (insoluble CuCl, tested by adding a few drops of water: Whitish sediment when water added = saturated with CuCl).
2) There should be free HCl in the solution (to keep the CuCl dissolved).
3) There should be a source of oxygen supplied over the course of the reaction (to keep the converting the CuCl back to CuCl2).


Of course, this an overly simplified explanation of the reaction, but it does describe the key points to keeping your solution fresh and ready to consume more copper.

Steve

 

[g_axelsson]

Melting metals is a chemical reaction where metals can be oxidized or reduced (again transfer of electrons), (just like other chemical reactions we perform with metals), depending on the metal, and how it reacts with oxygen or other chemicals in the melt, we can change the chemical properties of our melt to get a desired chemical reaction, in the melting environment or with flux or both.

The colored part of the above statement is totally wrong! Melting is a phase transition between a solid and liquid state. The chemical composition is unchanged.

H₂O -> H₂O

... which side is ice and which is water?

In a melt, just as in a solid or a solution chemical reactions can take place, but melting in it self is NOT a chemical reaction.

Göran, the physicist.

 

[butcher]

You are correct.
Actually that is true, if we are just talking about the pure metal being melted, and there is nothing for the metal to react chemically with in this melting process.

But in melting many metals this is normally not the case; there is something that will react chemically in the melt.


I understand that simply melting metal is not a chemical reaction.
Melting the metal can cause a chemical reaction with the metal and other components involved in the melt.

Would I be more politically correct if I said something like Melting of metals there is a chemical reaction that can take place,
where
Melting metals is a chemical reaction where metals can be oxidized or reduced (again transfer of electrons), (just like other chemical reactions we perform with metals), depending on the metal, and how it reacts with oxygen or other chemicals in the melt, we can change the chemical properties of our melt to get a desired chemical reaction, in the melting environment or with flux or both.

I may not know the best way to say some things.

 

[jason_recliner]

I find everything is connected and when I start looking for one answer it leads to more questions and so on. I started here wanting to know if the HCl was recovered as I've read nitric can be in some cases. A simple no would have got me nowhere. I believe that I'm incapable of linear thought. I kind of envy those you can just read Hoke and follow her directions. I need to be able to understand what's happening when I follow those instructions or I get confused.

Tell me about it, Doug! What was to be a "basic process" before starting, now has more little branches than a box hedge. So much here to read; it's all interconnected. Fortunately it's also all fascinating when one is in it for love not money. And my edumacation advances just by reading yours...

 

[lazersteve]

As a simplified acquaintance experiment for learning acid peroxide this is a great post:

Mason Jar AP

Practice the above technique on small batches so that you know what colors and procedure to use before you scale up. Scale up slowly and make note of the changes in your feed stock and how it affects the reaction. A lot of what you will learn from these small reactions carries into the scaled up reactions and helps you to better understand how to deal with pitfalls, when to add more reagents, and how to best harvest your foils.

Steve

 

[johnny309]

The AP method is good for fingers....for other types of gold bearing items...try other methods
The amount of copper to dissolve is ok for fingers in AP...because copper is only 30-40 um thick...but for pins(giving the fact that is a very slow reaction....and ...as I encountered Ag-Pd barrier,instead of the classic Ni...a lot of of work to recover the "extra materials")

P.S: The "GOOD" part of AP....is....for the one's that start now in ....recovering precious gold....is a way to teach them to be patient....(I'll bet that on the first and second try in using AP ....they lose 40% of their gold do to the hurry,filtration....).
After that they learn.

 

[lysdexic]

But in melting many metals this is normally not the case; there is something that will react chemically in the melt.

Many many years ago my first experiment in introductory physics we melted moth ball crystals (naphthalene) and then let the liquid cool and solidify. We had to record temperatures and such... as the rest of the class was cleaning up and getting ready to go to their next class my naphthalene was still liquid and well below the supposed "freezing" temperature. When I got my instructor's attention I got a private lesson in super cooling and then he told me to just tap the test tube, which I did and the liquid immediately became solid.

In my first year of electronics our project was to build an AM radio (superheterodyne receiver with 3 intermediate amplifier stages). Once mine was togather and hooked up to an antenna and an audio amplifier I tuned my IF amps (we didn't use any test equipment just trial and error) until I got audio output then tweaked them until I couldn't improve the sound quality any further. When I was about to call the Instructor over I bumped my radio and heard the "bump" from the speaker... so I tapped on the radio and it sounded the same as when you tap on a live microphone. Puzzled I called my Instructor over and showed him. He shook his head and laughed and said it's microphonic he started to explain but it was beyond the scope of the class he realized this so he just said it's a fluke and he's only ever seen it once before.

Both of those experiences gave me a chance to grow but there was I much bigger lesson I gained from those two experiences. Murphy's Law, anything that can go wrong, will go wrong.

In our case here, pure copper in a vacuum raised to the required melting temperature would be a simple state change from solid to liquid. Water or naphthalene change from solid to liquid at more moderate temperatures and water (not sure about naphthalene) is fairly nonreactive with air and whatever contaminants that would likely be present. As you and I both know we don't melt metals in real life in a vacuum or a clean room even. As you mentioned, copper readily oxidizes near it's melting temperature, traces of chlorides, nitrates, etc could be present and cause a reaction (I watched gold powder turn into a purple stain and a yellow stain on a melting dish while a larger portion went to "balloon heaven"). Fluxes are added to cause desirable chemical reactions. (random thought: alloys are just mixtures in the sense that they are not chemically combined).

You may not have said it correctly and I might have responded in like manor but I understood. How about:

When we melt metals chemical reactions will take place to a lessor or greater degree and we need to take steps to minimize or encourage those reactions as suits our needs or goals.