Thiosulphate Dropped--Testing for PM?

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"I guess the polarization of gold is too much to grasp for some. It's their insistence that gold must be reduced to a metallic in all cases. Their insistence that gold salts cannot be anionic and react like sulfur. Such stubbornness cannot be changed by reason and I don't intend to try anymore. I don't care if this thread is locked or not. I visit the forum to teach those that need my help, not to argue. Dr. Poe"


Dr. Poe I am learning and wish to understand.
But when you state something that is contrary to all of the other (known creditable) sources of information I have studied, it makes me question whether there is something I have yet to understand, or if your information is accurate, I personally do not come here to argue, I come here to learn, and I feel an attachment to the forum and feel protective over it, as it is a great source of knowledge for man, revealing secrets held since the beginning of man, when man has dealt with these metals and science many have tried to corrupt the true knowledge of its chemistry (practically changing it into magic), this forum has debunked much of this magic and revealed the true science behind the mystery, and this I hope is your mission too. Sadly I know there are men who for some reason wish to distort or corrupt knowledge, and work to create chaos (like I said I sincerely hope that is not the case here).

I am not opposed to learning something new, and admit I will never understand much of it, if it is possible for gold to plate out as salts, that notion does sound feasible (in this case it is not gold reduced but a salt that is reduced, for something to be reduced something else has to be oxidized). Please help me to understand the chemistry behind this, what is the chemistry involved, is the gold reduced as a gold metal, gold sulfate salt, gold sulfide salt (or some other salt), and what is oxidized, also what in this solution is chemically or electrically keeping the anions, and Cations from separating (elemental gold separating from the thiosulfate), or if they do separate, differently than gold metal and an thiosulfate or sulfate or sulfide how they do separate.

If I make a statement here on the forum and someone questions it I have be willing to back up that statement with facts.

Yes I have questioned your information as sometimes it has been very strange to me, different from much of what I have studied, and I know you are more educated than I am, but also I guess I just do not believe everything somebody writes, no matter what education level or paper they have, I have to find data to back that written statement or understand it better for myself, so hopefully you will show me.

Dr. Poe, I also know that for us to question you in this matter and they fashion has the effect to anger you, but also you have to understand how much this forum means to many of us here, and how important it is to us to keep the facts straight, I feel we are all rooting for you to just be misunderstood, and are hoping you can show us that our concerns are invalid;

So please help us to understand the chemistry of how gold plates out on the anode.

My mind is subject to change by reason, yes I am stubborn about what I know or believe in, so you do have your work cut out to educate me otherwise.
 
butcher said:
"I guess the polarization of gold is too much to grasp for some. It's their insistence that gold must be reduced to a metallic in all cases. Their insistence that gold salts cannot be anionic and react like sulfur. Such stubbornness cannot be changed by reason and I don't intend to try anymore. I don't care if this thread is locked or not. I visit the forum to teach those that need my help, not to argue. Dr. Poe"


Dr. Poe I am learning and wish to understand.
But when you state something that is contrary to all of the other (known creditable) sources of information I have studied, it makes me question whether there is something I have yet to understand, or if your information is accurate, I personally do not come here to argue, I come here to learn, and I feel an attachment to the forum and feel protective over it, as it is a great source of knowledge for man, revealing secrets held since the beginning of man, when man has dealt with these metals and science many have tried to corrupt the true knowledge of its chemistry (practically changing it into magic), this forum has debunked much of this magic and revealed the true science behind the mystery, and this I hope is your mission too. Sadly I know there are men who for some reason wish to distort or corrupt knowledge, and work to create chaos (like I said I sincerely hope that is not the case here).

I am not opposed to learning something new, and admit I will never understand much of it, if it is possible for gold to plate out as salts, that notion does sound feasible (in this case it is not gold reduced but a salt that is reduced, for something to be reduced something else has to be oxidized). Please help me to understand the chemistry behind this, what is the chemistry involved, is the gold reduced as a gold metal, gold sulfate salt, gold sulfide salt (or some other salt), and what is oxidized, also what in this solution is chemically or electrically keeping the anions, and Cations from separating (elemental gold separating from the thiosulfate), or if they do separate, differently than gold metal and an thiosulfate or sulfate or sulfide how they do separate.

If I make a statement here on the forum and someone questions it I have be willing to back up that statement with facts.

Yes I have questioned your information as sometimes it has been very strange to me, different from much of what I have studied, and I know you are more educated than I am, but also I guess I just do not believe everything somebody writes, no matter what education level or paper they have, I have to find data to back that written statement or understand it better for myself, so hopefully you will show me.

Dr. Poe, I also know that for us to question you in this matter and they fashion has the effect to anger you, but also you have to understand how much this forum means to many of us here, and how important it is to us to keep the facts straight, I feel we are all rooting for you to just be misunderstood, and are hoping you can show us that our concerns are invalid;

So please help us to understand the chemistry of how gold plates out on the anode.

My mind is subject to change by reason, yes I am stubborn about what I know or believe in, so you do have your work cut out to educate me otherwise.

Very well, I will try again:
I've stated several times that complex gold salts have a negative charge and therefore plate onto the positive

electrode. I've also stated that simple gold salts will plate onto the negative electrode. What if the two were mixed?
In the case of gold chloride (Au2Cl6 and acid gold chloride (HAuCl4), the difference starts with the addition of

hydrochloric acid. For normal plating, only a small amount of hydrochloric acid is added for conductivity. The salt

is mostly Au2Cl6 which hydrolyzes to Au+ and Cl- . The gold having a positive charge is plated upon the cathode

(negative electrode). The chlorine having a negative charge is released upon or attacks the anode. The small

percentage of acid gold chloride migrates to the positive electrode where it decomposes and then redissolves into

gold chloride (Au2Cl6) . A continuous circle is maintained until all the gold is plated upon the cathode.
However, if the ratio of molecules of HCl and of Au2Cl6 is equal, HAuCl4 is the only product and totally plates on

the anode. The hydrolysis of the salt is H+ AuCl4- . Hydrogen is released at the cathode and chlorine is

released at the anode where gold is decomposed. Part of the gold redissolves into the chlorine where it mixes with

excess HCl available and returns to the anode again to decomposes into gold and chlorine.
So to clarify; Where HCl is low, plating occurs on the cathode. Where HCl is high, plating occurs on the anode.
In the case of alkali complexes of gold: Hydrolysis is Na+ Au(S2O3)- where hydrogen and sodium is plated or

released on the cathode and the complex negative gold anion is decomposed by the anode.
In commerce, the plating of gold chloride, if a mistake is made and too much HCl is added to the solution, only

hydrogen is evolved at the cathode and chlorine at the anode until enough hydrogen escapes the solution then the

monovalent gold chloride (AuCl) is formed at the anode, mixes with HCl forming HAuCl+ which hydrolyzes to H+Au+

and Cl-, the gold migrates to the cathode where it deposits. In most all alkali complexes of gold, the gold is within

a negative anion and hydrolyzes to alkali+ and gold anion- where gold is deposited upon the anode.
In all alkali complexes of gold, the gold reacts as an acid, attacking the anode. If it were not an acid, how could

it form stable salts with alkali? A simple rule is to expect simple compounds of gold to build up on the cathode.
Complex gold salts give up gold to the anode. Dr. Poe
 
Very well, I will try again:
I've stated several times that complex gold salts have a negative charge and therefore plate onto the positive

As I understand it these dissolved salts are basically neutralized compounds (although they can be somewhat acidic (free acid in solution)) and these salts composed of (gold) positive metal Cation (gold atom missing electrons), and a negative Anion (chloride) (chlorine atom with excess electrons), (forming a complex salt neutral in solution),

which in an electrolytic cell these salts can be split, by forcing electrons through the cell, and creating a positive electrode (anode), and a negative electrode (cathode),

the positive gold ion is attracted to the cathode and is reduced(gains it’s electron back) to form metal and plate out at cathode,

chloride is attracted to the anode, and oxidized (looses electron)to form chlorine (depending on current and other cell conditions such as electrolyte would depend on how much of this chlorine is released as gas and how much is left in solution to attack and dissolve anode, as long as the anode is not inert to the chlorine), (if free acid in solution and again depending on current and cell condition’s the positive hydrogen can form gas at the cathode or stay in solution), (and chlorine can form a gas and either remain in solution or gas off).

I have heard where salts can be formed or separated in electrolysis, but I have never heard of them plating out as metal salts (Anion/Cation) on the anode, or cathode for that matter

(Anion and Cation plating to one electrode?? This statement baffles me),


electrode. I've also stated that simple gold salts will plate onto the negative electrode. What if the two were mixed?

As I understand it when gold plates out to cathode it is no longer a salt as it has gained an electron and becomes a metal, no longer bonded to the anion chloride (chlorine).

In the case of gold chloride (Au2Cl6 and acid gold chloride (HAuCl4), the difference starts with the addition of

hydrochloric acid. For normal plating, only a small amount of hydrochloric acid is added for conductivity. The salt

is mostly Au2Cl6 which hydrolyzes to Au+ and Cl- . The gold having a positive charge is plated upon the cathode

(negative electrode). The chlorine having a negative charge is released upon or attacks the anode. The small

percentage of acid gold chloride migrates to the positive electrode where it decomposes and then redissolves into

gold chloride (Au2Cl6) . A continuous circle is maintained until all the gold is plated upon the cathode.
However, if the ratio of molecules of HCl and of Au2Cl6 is equal, HAuCl4 is the only product and totally plates on

the anode. The hydrolysis of the salt is H+ AuCl4- . Hydrogen is released at the cathode and chlorine is

Here the above statement’s is very confusing to me. How much HCL was in solution would make no difference which plate the gold would be reduced at and how the Cations and Anions would split, the current of the cell can have some effect on gases evolved.

In your statement above “(H+ AuCl4-)”, I do not see it this way, yes Hydrogen is positive, but gold in this is also positive, the chlorine is the only Anion that is negative, the way you state this you make it seem as though the Cation gold becomes an Anion when combined with chlorine, I do not know if that is what your stating but I beg to differ.


released at the anode where gold is decomposed. Part of the gold redissolves into the chlorine where it mixes with

excess HCl available and returns to the anode again to decomposes into gold and chlorine.
So to clarify; Where HCl is low, plating occurs on the cathode. Where HCl is high, plating occurs on the anode.
In the case of alkali complexes of gold: Hydrolysis is Na+ Au(S2O3)- where hydrogen and sodium is plated or

Here again you show gold with a negative charge? Yes it is a salt in solution but the gold is still missing an electron and the thiosulfate has an excess electron which makes this salt bond, as far as I know if we gave the gold back an electron through electrolysis it would plate out deposit or whatever you wish to call it at the cathode.

released on the cathode and the complex negative gold anion is decomposed by the anode.
In commerce, the plating of gold chloride, if a mistake is made and too much HCl is added to the solution, only

Gold is a Cation not an anion, how did it change polarity?

hydrogen is evolved at the cathode and chlorine at the anode until enough hydrogen escapes the solution then the

monovalent gold chloride (AuCl) is formed at the anode, mixes with HCl forming HAuCl+ which hydrolyzes to H+Au+

and Cl-, the gold migrates to the cathode where it deposits.

In most all alkali complexes of gold, the gold is within

a negative anion and hydrolyzes to alkali+ and gold anion- where gold is deposited upon the anode.
In all alkali complexes of gold, the gold reacts as an acid, attacking the anode. If it were not an acid, how could

it form stable salts with alkali? A simple rule is to expect simple compounds of gold to build up on the cathode.
Complex gold salts give up gold to the anode. Dr. Poe



.The alkali has excess electrons, which gold can take an electron from, to from the stable complex as an alkali solution of gold.

I do not see this as gold acting as an acid, but if that is how you explain it I am fine with that.

Dr. Poe, I do agree with much of what you stated, I can see you do have a very good understanding of most of the chemistry and principles involved,

(But some of it also seems to wander off of the normal principles or at least how I have learned them).

But I still cannot see where (especially in an acid solution of electrolysis where these salts would plate out.

The statements surrounding H+ AuCl-, seem like your saying that only the hydrogen is missing an electron and the AuCl as a salt has excess electrons,

When in my mind the Hydrogen is missing its electron, the gold is missing an electron, and only chlorine has the excess of electrons to make the complex HAuCl3.


Ferrell stated they observed gold at the anode, and I have no doubt that it could be true, but I also have to wonder which pole they are describing, or if these are in fact salts of gold plating out or if it is elemental gold.

And I am even more confused by some of the descriptions above most of which is exactly like I have learned it, but some parts of the description seem to change the polarity of these atoms as they become salt complexes, Dr. Poe I still either think one of us does not understand this fully (I can admit I do have a limited understanding), but from what I do understand, it also seems to me by your description above you do not have a complete understanding either, or one of us needs to help the other to come to the same understanding on this subject,

I guess I need more help understanding how this salt complex can have a polarity as a whole and plate to the anode,

(How can the (Cation) oxidized atom of gold missing electrons become and (Anion).

When I see the complex as dividing and the atoms each being oxidized or reduced at their respective poles, (gold atom gaining electron at cathode and plating out there), (and chlorine being oxidized and loosing electrons at anode), (and if elemental gold was the anode its atom would give up an electron to the chlorine and dissolve into solution as a complex of gold chloride).


Dr. Poe I like your discription it is very well done, but can you clarify some of this confusion for me.


Thanks again for being willing to do this.
 
Dr.Poe please understand the forum is the only place on the Internet where complete and honest instructions as to how to refine and recover precious metals are laid out in simple terms. You as many other members, use a screen name which reveals little as to who you are or your actual identity, so your going to be questioned. The members that contribute to the debates and the moderators regard this forum with huge pride and no one is beyond been called to either explain or give full disclosure about a process or method outlined on here. The chemistry and physics behind this is way over my head but I live in hope that it will be of use to some of the members in their search for ways to recover and refine gold.
Perhaps one way to prove this method is for a member to submit samples to someone like Butcher,who understands a lot more than me and is well respected, for a controlled test to prove the theory which to many of us seems beyond understanding.
Dr.Poe if what you have posted is correct please don't take offence, we all want to learn but we need to prove the method so that what is written on the forum remains valid and correct and has the backing of all involved.
 
[Here the above statement’s is very confusing to me. How much HCL was in solution would make no difference which plate the gold would be reduced at and how the Cations and Anions would split, the current of the cell can have some effect on gases evolved.] Gold isn't corroded by chlorine except in the presence of water, HCl or at high temperatures. In fact Au+3 is reduced by chlorine, a reversible reaction in HCl or water unless the chlorine is removed from the reaction. Once reduced, the gold becomes a colloidal particle with a negative static charge attracting it to a positive charged anode. Au2Cl6 and HAuCl4 are two different compounds and hydrolyze differently.

[In your statement above “(H+ AuCl4-)”, I do not see it this way, yes Hydrogen is positive, but gold in this is also positive, the chlorine is the only Anion that is negative, the way you state this you make it seem as though the Cation gold becomes an Anion when combined with chlorine, I do not know if that is what your stating but I beg to differ.]
The negative charge or Cl4 is -4 which is one electron more than the gold's +3 needs leaving the compound with a negative charge or -1. Gold is not the anion, but the compound of gold with four chlorines is the anion. At the anode, gold steals chlorine's electrons which in turn chlorine steals electrons from the solution. Over all, leaving the gold with a charge of zero.
A static charge on the surface draws the gold metallic particle to the anode where it also is neutralized.
Change the H+ to Na+ and change the AuCl4- to Au(S2O3)- and the same reasons happen in alkaline solutions.
Drop a wafer (1/2 a zinc penny) into a solution of HAuCl4 and the gold doesn't plate onto the copper, but instead corrodes the zinc depositing gold and turning the zinc black to the naked eye. Were you correct the gold would plate onto the copper.
The copper being the cathode to the zinc's anode. But this doesn't happen. The gold clings to the zinc.
Do the same experiment with Au2Cl6 and the gold plates to the copper.
I have a question. If someone has never plated gold from a sodium thiosulfate solution should they confess to being an expert on the subject? No, I am not referring to you. Dr. Poe ( real name and title) PHD Geochemical Research
 
nickvc said:
Dr.Poe please understand the forum is the only place on the Internet where complete and honest instructions as to how to refine and recover precious metals are laid out in simple terms. You as many other members, use a screen name which reveals little as to who you are or your actual identity, so your going to be questioned. The members that contribute to the debates and the moderators regard this forum with huge pride and no one is beyond been called to either explain or give full disclosure about a process or method outlined on here. The chemistry and physics behind this is way over my head but I live in hope that it will be of use to some of the members in their search for ways to recover and refine gold.
Perhaps one way to prove this method is for a member to submit samples to someone like Butcher,who understands a lot more than me and is well respected, for a controlled test to prove the theory which to many of us seems beyond understanding.
Dr.Poe if what you have posted is correct please don't take offence, we all want to learn but we need to prove the method so that what is written on the forum remains valid and correct and has the backing of all involved.
A man had never made a map, yet disputed the map makers with decades of experience. Travel west to find the far East?
How ridiculous did this Christopher Columbus sound to all but one queen. Mrs. Ferrell proved my points. Does someone question her integrity? Does someone need proof? Let them extract gold with an alkali thiosulfate and use two titanium plates. Then tell us, Which electrode plated the copper and the silver. Which electrode plated the gold?
For me, the copper and the silver plated on the cathode, but the gold always plated to the anode. Dr. Poe
 
First Dr. Poe, I really appreciate your discussion on this.

{Gold isn't corroded by chlorine except in the presence of water, HCl or at high temperatures.}

I was under the impression gold or platinum group metals were attacked by chlorine gas alone, I also understood it was at high temperatures that this reaction occurs, or under the conditions of acids when mixed with the chlorine in solution. Gold powders will dissolve in chlorine gas >180 deg C.

In the electrochemical cell, I was under the impression it was an external power supply that was one of the causes for the reactions that would not normally occur without the power supply’s force in moving these electrons and through the cell, although these electrons are actually moving through these chemical reactions not only by the force of the external power source but also by the atomic charge on these atoms in solution, Electrons and ions transfering electrons in solution, and also by the charge of the elemental atoms in the electrodes (being forced to a polarity by the external source).

So where an anode may not normally be attacked or corroded by a solution (or chlorine in solution), it is this external power source that is the driving force behind this domino theory.

Lets take a gold chloride solution for example, and a pure gold anode, a pure gold cathode, no free acid or oxidizer, no external power source, hooked up to our anode or our cathode, gold chloride solution in equilibrium, no more gold dissolving at either electrode, we would have no electron movement through this cell from atom to atom.
But if we hooked up a battery, or a power supply to our two gold electrodes, now making one gold electrode (electron poor), (the cells anode).
Making the other gold electrode (electron rich), (the cells cathode).
Now we are starting this domino reaction through our cell.
Gold (Cation) in solution around the cathode will plate out as metal onto the cathode (the cathode’s excess electrons giving the gold an electron reducing the gold to metal, (gold was a Cation missing an electron, and forming a complex salt in solution with the anion chloride’s).
Now this salt complex has been broken as well as its bond, this leaves a freed chloride’s in solution as these chloride’s move’s to the vicinity of the gold (electron poor) anode, the chloride’s are oxidized (loss of atom) to chlorine gases, (these free chlorine gas atom’s can now join with a gold atom from the anode and become a salt complex with the chlorines to again form gold chloride in solution.


I was also under the impression that it was this external power source that was the driving force behind the flow of these electrons through the electrochemical cell, and also the driving force for the chlorine generated in this cell to dissolve the pure gold at the anode.


{In fact Au+3 is reduced by chlorine, a reversible reaction in HCl or water unless the chlorine is removed from the reaction. Once reduced, the gold becomes a colloidal particle with a negative static charge attracting it to a positive charged anode. Au2Cl6 and HAuCl4 are two different compounds and hydrolyze differently.}

Dr. Poe I really do not know how to respond to this statement, Au+3 gold (III) chloride, would not normally be in solution or salt alone,(as I see it it is already bonded with chlorides or another halide) here the gold is missing three electrons, and I assume if we are discussing a chloride solution it would be a gold chloride salt in solution, AuCl3 (dilute gold dissolved in aqua regia, one gold atom bonded with three chlorine atoms), HAuCl4 (highly acidic solution of gold dissolved in aqua regia, one gold atom bonded with four chlorine atoms), or Au2Cl6 (a dehydrated salt of gold from heating aqua regia, two gold atoms bonded with six chlorine atoms).
How would the gold salt in this solution be reduced (gain electrons from chlorine) unless the acidity changed, or from some other reaction or outside force caused the original gold complex changed valence, or to transfer electrons, and if we are talking about in electrolytic solutions, unless we change the water or acid content.



[In your statement above “(H+ AuCl4-)”, I do not see it this way, yes Hydrogen is positive, but gold in this is also positive, the chlorine is the only Anion that is negative, the way you state this you make it seem as though the Cation gold becomes an Anion when combined with chlorine, I do not know if that is what your stating but I beg to differ.]

{The negative charge or Cl4 is -4 which is one electron more than the gold's +3 needs leaving the compound with a negative charge or -1. Gold is not the anion, but the compound of gold with four chlorines is the anion.}

I really do not understand the math here, if we are speaking of gold (III) chloride, HAuCl4, yes I see this one gold atom bonded with four chlorine atoms in this acidic solution, the one gold atoms bonded by sharing an electron with these chlorines, but I also see this one gold atom (Cation) bonded to the four chlorine (Anions), and I also see how they could easily divide, or separate in an electrolytic cell, Dr. Poe I do have to admit you make me scratch my head, and are making me want to read more books to see if I am missing something here, but honestly I do not see this compound as an Anion (having a negative charge) (or having one excess electron), (but I also never seen these atoms in person and cannot picture them in my head).

{At the anode, gold steals chlorine's electrons which in turn chlorine steals electrons from the solution. Over all, leaving the gold with a charge of zero.
A static charge on the surface draws the gold metallic particle to the anode where it also is neutralized.}

The way I learned this the chloride at the anode is oxidized to chlorine gas and the gold atom of the anode (electron poor gold anode) creates a gold complex in solution (sharing electrons) to become a neutral salt in solution, (the hydrogen being a positive Cation is reduced at the cathode as gas or kept in solution depending on cells conditions).

{Change the H+ to Na+ and change the AuCl4- to Au(S2O3)- and the same reasons happen in alkaline solutions.
Drop a wafer (1/2 a zinc penny) into a solution of HAuCl4 and the gold doesn't plate onto the copper, but instead corrodes the zinc depositing gold and turning the zinc black to the naked eye. Were you correct the gold would plate onto the copper.
The copper being the cathode to the zinc's anode. But this doesn't happen. The gold clings to the zinc.}

In my mind depending on how much of this acidic solution and how much penny was involved, the acidic solution would attack the zinc (being very reactive inside the penny with a vigorous reaction this zinc would begin to replace gold from solution (cementing the gold), making a zinc chloride solution, and if gold was totally cemented form solution it would not attack the copper, but if the zinc was used up and there was still gold in solution then the copper would begin to replace gold from solution also. Basically until the metal lower in the reactivity series had replace all of the gold in solution.
But in this highly acidic gold solution I can also see it dissolving the copper plated zinc penny (zinc reacting faster of course), and depending on how much solution we are talking about end up with a zinc chloride solution with gold and copper metal powders in the bottom of this vessel.

Also if you are saying the gold is reduced first by the higher of the two metals (zinc and copper in the reactivity series I agree.



{Do the same experiment with Au2Cl6 and the gold plates to the copper.}

Well that is slightly over my head, as I always thought Au2Cl6 was a salt of evaporated gold chloride solution, and as reactive as zinc is I believe if this copper zinc penny was left in the (more neutral, but still acidic powders) the I would have to say I believe gold would still be reduced to metal by zinc first then by gold, but I am just speculating as I do not have any experience with Au2CL6.

{I have a question. If someone has never plated gold from a sodium thiosulfate solution should they confess to being an expert on the subject? No, I am not referring to you. Dr. Poe ( real name and title) PHD Geochemical Research}

Dr. Poe thank you again for this discussion and I must say it is tiring out my brain as I Have spent all night on this discussion when I should have been in bed 8 hours ago, and have to go to work here in a few more hours, you have brought up several things that I will study, and like I said before there is no doubt you are more educated than I am, and I do hope we can continue to share these Idea’s, As your statements here still leave me with some unanswered questions on this subject.

Also I have stated from the beginning, that I have had no experience in plating gold from, or even leaching gold from a thiosulfate solution, I have never confessed to being an expert in anything, much less gold refining or recovery, electrolysis or any other subject for that matter, although I have tried to learn as much as I can about this subject of these metals, since becoming a backyard refiner.

Well I have to clean up for work, I also would like to discuss these Ideas further when I have more time, and I will study some more on these thoughts when I have time.

(Real name, and title)
Butcher, unprofessional back yard refiner.
 
butcher said:
First Dr. Poe, I really appreciate your discussion on this.

{Gold isn't corroded by chlorine except in the presence of water, HCl or at high temperatures.}

I was under the impression gold or platinum group metals were attacked by chlorine gas alone, I also understood it was at high temperatures that this reaction occurs, or under the conditions of acids when mixed with the chlorine in solution. Gold powders will dissolve in chlorine gas >180 deg C.

In the electrochemical cell, I was under the impression it was an external power supply that was one of the causes for the reactions that would not normally occur without the power supply’s force in moving these electrons and through the cell, although these electrons are actually moving through these chemical reactions not only by the force of the external power source but also by the atomic charge on these atoms in solution, Electrons and ions transfering electrons in solution, and also by the charge of the elemental atoms in the electrodes (being forced to a polarity by the external source).

So where an anode may not normally be attacked or corroded by a solution (or chlorine in solution), it is this external power source that is the driving force behind this domino theory.

Lets take a gold chloride solution for example, and a pure gold anode, a pure gold cathode, no free acid or oxidizer, no external power source, hooked up to our anode or our cathode, gold chloride solution in equilibrium, no more gold dissolving at either electrode, we would have no electron movement through this cell from atom to atom.
But if we hooked up a battery, or a power supply to our two gold electrodes, now making one gold electrode (electron poor), (the cells anode).
Making the other gold electrode (electron rich), (the cells cathode).
Now we are starting this domino reaction through our cell.
Gold (Cation) in solution around the cathode will plate out as metal onto the cathode (the cathode’s excess electrons giving the gold an electron reducing the gold to metal, (gold was a Cation missing an electron, and forming a complex salt in solution with the anion chloride’s).
Now this salt complex has been broken as well as its bond, this leaves a freed chloride’s in solution as these chloride’s move’s to the vicinity of the gold (electron poor) anode, the chloride’s are oxidized (loss of atom) to chlorine gases, (these free chlorine gas atom’s can now join with a gold atom from the anode and become a salt complex with the chlorines to again form gold chloride in solution.


I was also under the impression that it was this external power source that was the driving force behind the flow of these electrons through the electrochemical cell, and also the driving force for the chlorine generated in this cell to dissolve the pure gold at the anode.


{In fact Au+3 is reduced by chlorine, a reversible reaction in HCl or water unless the chlorine is removed from the reaction. Once reduced, the gold becomes a colloidal particle with a negative static charge attracting it to a positive charged anode. Au2Cl6 and HAuCl4 are two different compounds and hydrolyze differently.}

Dr. Poe I really do not know how to respond to this statement, Au+3 gold (III) chloride, would not normally be in solution or salt alone,(as I see it it is already bonded with chlorides or another halide) here the gold is missing three electrons, and I assume if we are discussing a chloride solution it would be a gold chloride salt in solution, AuCl3 (dilute gold dissolved in aqua regia, one gold atom bonded with three chlorine atoms), HAuCl4 (highly acidic solution of gold dissolved in aqua regia, one gold atom bonded with four chlorine atoms), or Au2Cl6 (a dehydrated salt of gold from heating aqua regia, two gold atoms bonded with six chlorine atoms).
How would the gold salt in this solution be reduced (gain electrons from chlorine) unless the acidity changed, or from some other reaction or outside force caused the original gold complex changed valence, or to transfer electrons, and if we are talking about in electrolytic solutions, unless we change the water or acid content.



[In your statement above “(H+ AuCl4-)”, I do not see it this way, yes Hydrogen is positive, but gold in this is also positive, the chlorine is the only Anion that is negative, the way you state this you make it seem as though the Cation gold becomes an Anion when combined with chlorine, I do not know if that is what your stating but I beg to differ.]

{The negative charge or Cl4 is -4 which is one electron more than the gold's +3 needs leaving the compound with a negative charge or -1. Gold is not the anion, but the compound of gold with four chlorines is the anion.}

I really do not understand the math here, if we are speaking of gold (III) chloride, HAuCl4, yes I see this one gold atom bonded with four chlorine atoms in this acidic solution, the one gold atoms bonded by sharing an electron with these chlorines, but I also see this one gold atom (Cation) bonded to the four chlorine (Anions), and I also see how they could easily divide, or separate in an electrolytic cell, Dr. Poe I do have to admit you make me scratch my head, and are making me want to read more books to see if I am missing something here, but honestly I do not see this compound as an Anion (having a negative charge) (or having one excess electron), (but I also never seen these atoms in person and cannot picture them in my head).

{At the anode, gold steals chlorine's electrons which in turn chlorine steals electrons from the solution. Over all, leaving the gold with a charge of zero.
A static charge on the surface draws the gold metallic particle to the anode where it also is neutralized.}

The way I learned this the chloride at the anode is oxidized to chlorine gas and the gold atom of the anode (electron poor gold anode) creates a gold complex in solution (sharing electrons) to become a neutral salt in solution, (the hydrogen being a positive Cation is reduced at the cathode as gas or kept in solution depending on cells conditions).

{Change the H+ to Na+ and change the AuCl4- to Au(S2O3)- and the same reasons happen in alkaline solutions.
Drop a wafer (1/2 a zinc penny) into a solution of HAuCl4 and the gold doesn't plate onto the copper, but instead corrodes the zinc depositing gold and turning the zinc black to the naked eye. Were you correct the gold would plate onto the copper.
The copper being the cathode to the zinc's anode. But this doesn't happen. The gold clings to the zinc.}

In my mind depending on how much of this acidic solution and how much penny was involved, the acidic solution would attack the zinc (being very reactive inside the penny with a vigorous reaction this zinc would begin to replace gold from solution (cementing the gold), making a zinc chloride solution, and if gold was totally cemented form solution it would not attack the copper, but if the zinc was used up and there was still gold in solution then the copper would begin to replace gold from solution also. Basically until the metal lower in the reactivity series had replace all of the gold in solution.
But in this highly acidic gold solution I can also see it dissolving the copper plated zinc penny (zinc reacting faster of course), and depending on how much solution we are talking about end up with a zinc chloride solution with gold and copper metal powders in the bottom of this vessel.

Also if you are saying the gold is reduced first by the higher of the two metals (zinc and copper in the reactivity series I agree.



{Do the same experiment with Au2Cl6 and the gold plates to the copper.}

Well that is slightly over my head, as I always thought Au2Cl6 was a salt of evaporated gold chloride solution, and as reactive as zinc is I believe if this copper zinc penny was left in the (more neutral, but still acidic powders) the I would have to say I believe gold would still be reduced to metal by zinc first then by gold, but I am just speculating as I do not have any experience with Au2CL6.

{I have a question. If someone has never plated gold from a sodium thiosulfate solution should they confess to being an expert on the subject? No, I am not referring to you. Dr. Poe ( real name and title) PHD Geochemical Research}

Dr. Poe thank you again for this discussion and I must say it is tiring out my brain as I Have spent all night on this discussion when I should have been in bed 8 hours ago, and have to go to work here in a few more hours, you have brought up several things that I will study, and like I said before there is no doubt you are more educated than I am, and I do hope we can continue to share these Idea’s, As your statements here still leave me with some unanswered questions on this subject.

Also I have stated from the beginning, that I have had no experience in plating gold from, or even leaching gold from a thiosulfate solution, I have never confessed to being an expert in anything, much less gold refining or recovery, electrolysis or any other subject for that matter, although I have tried to learn as much as I can about this subject of these metals, since becoming a backyard refiner.

Well I have to clean up for work, I also would like to discuss these Ideas further when I have more time, and I will study some more on these thoughts when I have time.

(Real name, and title)
Butcher, unprofessional back yard refiner.
In physics, math and chemistry, radicals cancel each other out and so are most often written with the canceled radicals omited. This takes away some of the knowledge presented to short cut to the end products. For instance the addition of sulfuric acid to sodium chloride solutions is often written omitting the intermediate formation of sodium bi-sulfate.
I also was not referring to you as one that's not ever plated gold from sodium thiosulfate solutions. I was referring to a phantom member of a name simular to Great Silly Poser. Gold acid doesn't get it's name from addition of acid, but because it actually becomes an acid. Dr. Poe
 
Hello friends:
It is a privilege to participate in a forum of this type and learn about different ideas about topics that we meet.
It would be very interesting to see a contribution to practical data and photos on the theme proposed by the Dr.Poe.
 
As far as I'm concerned, butcher really, really, really gets this.


I didn't read through the whole thread, just butcher's query and Dr. Poe's response, now that I see some more of the same crap being perpetrated elsewhere.

I'm not going to spend the time it would take to thoroughly go through this. Suffice it to say, we can have a high level "gold by wohwill cell" thread and make it fairly detailed. Might be worthwhile so we don't have people thinking that you can use chlorine gas to reduce your gold with like it's some practical thing. I just think of all the times I used nice dry chlorine gas (or bromine and iodine) to make AuCl3 (or Au2Cl6) for making into various adducts or sale. Great oxidizer for gold. Works well in solution with HCl since gold takes oxidizing AND complexing conditions to dissolve (cyanide needs air or peroxide, chloride needs free chlorine or nitroysl chloride etc.).
 
Finally Lou mentions the since more than 100 years well known Wohlwill-electrolysis, which shows clearly, that pure, refined gold always, without exception, is deposited at the cathode. The cathode is the electrode connected to the negative current-lead, constantly delivering the electrons necessary, to reduce [AuCl4](-)-anions to metallic gold, Au(0), which deposits on the cathode, and "liberating" 4 Cl(-)-anions going into solution, keeping the high free chloride concentration (i.e. the concentration of Cl(-)-anions not bound to an Au(III)-center) needed, to bring about dissolution of the gold-anode, Au(0), at a more or less constant high level. The anode (the metallic gold, to be purified) is the electrode, connected to the positive current lead, delivering, expressed in Dr. Poe's terminology, the holes necessary (i.e. picking up electrons from whatever it is in solution), to bring about oxidation of Au(0) to Au(III), regenerating AuCl4(-)-anions, which are again reduced at the cathode. Thus the current (electrons) flows from the negative pole of the rectifier to the cathode, then through the (gold)-solution, transported by anions (mainly chloride), being oxidized at the anode. In this simple overall-scheme of the Wohlwill-electrolysis one can not make the difference, if first at the anode elemental chlorine is generated, which oxidizes Au(0), or, if Au(0), nearest to the anode surface looses directly three electrons through the current flowing, being directly oxidized to Au(III), which immediately is stabilized in solution as [AuCl4](-) through the abundantly present chloride-ions. This simple scheme also explains, why Wohlwill-refining functions only under certain well defined conditions, namely a very high concentration of free chloride-ions (free HCl) and a high concentration of dissolved gold (as HAuCl4). If these conditions are not fulfilled, only impure gold is deposited at the cathode (i.e. different dissolved substances are deposited also) and/or the gold-anodes don't dissolve, and gaseous chlorine is evolved.

freechemist
 
Hi, Ferrell,

It's been quite a long time since I posted something on your topic, which presently is in an elusive discussion about a lot of different things, exempt your ore and it's leaching by a thiosulfate solution. I have read a lot of posts about the subject, and most evident to me is the lack of systematic procedure in all of your experiments. Please excuse me, if I am wrong, but to me it seems, that even today you still don't know exactly what you are dealing with. To me a systematic approach means, that I have to know, for every single experiment:

1.) Exact quantity and exact individual precious metal content of every individual ore-sample to be examined.

2.) What goes in (x g Au, y g Ag,etc.) has to come out. Thus, for every leach-experiment it is very useful to analyze the leach-solution for it's PM-content from time to time, until a constant, no more changing PM-concentration (if there ever are any PMs) is reached. This also helps to find best leaching conditions.

3.) The same holds true for the recovering of the dissolved values.

4.) Before experiments you have to do some calculations. At least you should know the minimal needed quantities of thiosulfate to extract the total PMs contained in the ore-samples quantitatively. The stoichiometric composition of the complex anions to be extracted are most probably [Au(S2O3)2(3-)] and [Ag(S2O3)2(3-)]. Be aware, that always an excess of thiosulfate has to be present, to avoid formation of insoluble sulfides.

5.) You always have to do "blank-experiments" for comparison, especially in recovering. That means, you have to treat a sample of freshly prepared, non-loaded leach-solution the same way, as you intend to treat the loaden leach-solution, and observe what happens in a very detailed manner. Or, on the other side, if you don't find any PMs in your leach, you have to add exactly measured amounts of PMs to your ore-samples, ideally in form of metal or compounds like they should be present in your ore before leaching, in order to find out if your leaching procedure is really functioning.

You see, what you intend to do IMHO is much too complex for you and overstrains your capabilities and competences by far. Thus, the only thing I can recommend you is to enter into relationship with trustful professional recoverers/refiners and sell your ore for the best available price.

In my first post from december, 18 I supposed as a blank experiment, to add some iron(II)sulfate solution to a sample of freshly prepared, non-loaded leach-solution, being quite sure, that you will observe the same phenomena as in the assumed "loaded leach". Much later you posted some nice pictures of electrolysis-experiments, where I am quite convinced too, that you would have observed the same or similar phenomena, using samples of freshly prepared, non-loaded leach-solution.

Good luck and regards,

freechemist
 
I found these publications detailing the leaching with thiosulphate.
Murdoch University site are unprotected and can be downloaded.
http://researchrepository.murdoch.edu.au/422/2/02Whole.pdf
http://researchrepository.murdoch.edu.au/672/2/02Whole.pdf
 
renatomerino said:
I found these publications detailing the leaching with thiosulphate.
Murdoch University site are unprotected and can be downloaded.
http://researchrepository.murdoch.edu.au/422/2/02Whole.pdf
http://researchrepository.murdoch.edu.au/672/2/02Whole.pdf


Thank you for the link renatomerino.
 
Hello all , how are tricks?
I hope all is well!

" I was referring to a phantom member of a name simular to Great Silly Poser. "

Dr. Poe , please excuse my ignorance , but as a *noobie* on this forum myself , I am as yet still unfamiliar with the names of many of the active contributing members.
Just so I am current , could you please elaborate to whom you are reffering in the above comment?
I don't mean to be rude , it's just that I find many of your posts cryptic at the best of times and trying to decipher pseudo names only complicates things further for me.
Many thanks in advance ,
Chris
 
kuma said:
Hello all , how are tricks?
I hope all is well!

" I was referring to a phantom member of a name simular to Great Silly Poser. "

Dr. Poe , please excuse my ignorance , but as a *noobie* on this forum myself , I am as yet still unfamiliar with the names of many of the active contributing members.
Just so I am current , could you please elaborate to whom you are reffering in the above comment?
I don't mean to be rude , it's just that I find many of your posts cryptic at the best of times and trying to decipher pseudo names only complicates things further for me.
Many thanks in advance ,
Chris

He means me. Note the same GSP initials. Dr.Poe has complained about people insulting him. Maybe he should worry about the log in his own eye before worrying about the spec in someone else's.
 
This is an interesting thesis that I recommend.
The site is open and you can download.
https://circle.ubc.ca/bitstream/handle/2429/14499/ubc_2003-0505.pdf?sequence=1
 
Thanks to GSP, Lou, freechemist, and those others who make a genuine contribution to the advancement of the goals of this site.
I have disconnected from anything involving parties who I feel I am not able to understand.
I think often of Harold's signature line and apply what I understand to be its meaning.
I do these things because I wish to be more like kadriver.
 
Hi Everybody!

Great respect and thanks to everybody here on this site! I think that the results shown in the photos say alot. I was also perplexed about the gold depositing semi-reduced at the positive electrode. But it's an interesting discovery, one must admit. I think it's not all that hard to try. Proof is always in the pudding!
I am very interested in seeing the developing results in this process. Soon I will be going off to an African country to work dissolving and refining gold for my friends in a Russian company. They were not at all pleased with their own experiments with mercury and want a more effecive and safe technology. It looks like blue/grey clay, so I'm afraid of preg robbing. Looks like this thiosulfate process is the way to go for me.
Thank you very much for all that you have already shared in this thread, Mrs. Ferrell and Dr. Poe!

Best Regards,
Paul
 

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