Copper cementation process and results

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spoke27

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Hello I am in a bit of trouble with a mineral that I have been dealing with for a long time, like the lizard chasing its tail. For some, this is an unnecessary situation, but this is my hobby. I am aware of this is a dangerous hobby. Therefore, I would like to share with you the results I have achieved with Bakır, I would be glad if those who have the idea can share with me here. I think you will contribute to others ..
First of all, I took the mine sample and passed it through a pre-leach process. I used HCL here. I tested it with Tin Chloride at every step of the process. Then I did AR and filtered it. I picked up sulfuric acid and got a white precipitate and filtered it out too.
Then I added a Copper without any Denox wire and then a copper plate. I did not use any heat or air. It took about 3 days for the bubbles to come out and I did this completely in a large plastic canister in a place away from people.
now I am sharing the results here, thank you in advance to anyone who has an idea of what they are or can tell me if there is a mistake I made. I will add Notes on the Pictures Please take them into consideration.
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spoke27

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I wash and will Dry and it will go XRF
TY
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filtred solition you can see top Of beaker like bismute like tin like oil ??
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g_axelsson

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Looks like iron hydroxide, or in other words rust.

If you run out of acid in your sample while cementing on copper the pH will rise and iron hydroxide will start to precipitate. Since you started with aqua regia, just add a bit of HCl to see if the brown precipitate dissolves.

It also explains the "oily" film on the surface, it's a thin layer of rust that is formed at the surface when some of the acid evaporates and the pH rises. You can see it in nature when iron rich groundwater seeps out of the ground. It's the same process that forms bog iron deposits.

Göran
 

g_axelsson

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Quick googling...

https://ei.lehigh.edu/envirosci/enviroissue/amd/links/chem1.html
In the presence of oxygen, ferrous iron oxidizes to ferric iron, and ferric hydroxide forms a yellowish-orange solid (commonly called yellow boy), which precipitates at pH >3.5.

Close enough if the concentration of iron is high.

Göran
 

spoke27

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g_axelsson said:
Quick googling...

https://ei.lehigh.edu/envirosci/enviroissue/amd/links/chem1.html
In the presence of oxygen, ferrous iron oxidizes to ferric iron, and ferric hydroxide forms a yellowish-orange solid (commonly called yellow boy), which precipitates at pH >3.5.

Close enough if the concentration of iron is high.

Göran

Yes That yellow discharge dissolves in HCL. I had bought a bead that did not react to the magnet at all when I melted this mine using copper as a collector metal. Well, when I thought why this happened to me, the only answer that came to my mind was this .. I added hot water to the reaction and heated this hot water in an aluminum container. I thought maybe that's why it could be. The metallic residue on the copper wire is still there. And those that look like whitish salt still remain. I could have waited for the copper to come out or come on Bismut .. But where is the iron and where is the copper? I usually work by dividing the Solutions into two parts. I did not add water to the other part. Let me assign his picture. I think the importance of working clean has been revealed once more.
 

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g_axelsson

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The white deposit on the copper wire could be copper chloride, just as the white precipitate.
Does it dissolve in HCl too, giving a dark brown solution?

Göran
 

spoke27

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g_axelsson said:
The white deposit on the copper wire could be copper chloride, just as the white precipitate.
Does it dissolve in HCl too, giving a dark brown solution?

Göran

Hi Göran White deposit waiting in HCL at few hours s and it is not dissolve..
 

g_axelsson

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Then I don't know what it is. At least it isn't copper chloride.

Göran
 

butcher

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Being a whitish or gray metal crust of elemental metal or a salt of a metal makes me doubt values, unless maybe owe consider of silver, most of the noble metals will cement out as a black color.

this could be a salt of most anything or a metal or combination, the pH adjustment of the solution could produce most anything from solution, you not only had copper replacing metal ions from solution but also metals coming out of solution as insoluble salts oxides or hydroxides, thus the deposit could be most anything, but unlikely of anything of much value.

Just because it will not dissolve in HCl or aqua regia will not tell us much, except it is metal or salt of a metal or combination , such as an insoluble chloride, like mercury silver or lead.. Or a metal resistant to the acids or the oxidizers involved, or one that-oxidizes or passivates into an insoluble crust too hard for the acid to penetrate.

Weigh a small sample in a test tube boil in water does it loose any weight or volume?
how does a a small sample react in in dilute HNO3?

Will a small sample in a test tube of it dissolve in an alkali solution? Strong ammonia solution or sodium hydroxide solution ? Does the deposit have amphoteric metal properties?

How does it react to potassium dichromate or Schwerters solution?

https://www.sciencecompany.com/How-to-Test-Gold-Silver-and-Other-Precious-Metals.aspx
 

spoke27

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Thank you for the answers. The state in the beaker is only HCL in the left tube AR and in the other only the white residue in the HNO3 test tubes has been waiting for 3 days, maybe there may have been some dissolution. It is really difficult to say something by looking at these. As a result, the color I expected was not white, of course, but as you mentioned, different conditions lead to different results. This must be the reason why they call it chemistry. Even though the remains on the copper are white, I saw that when I heated it, it separated as a black residue, I do not know if it has any meaning.
 

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FrugalRefiner

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Without re-reading the whole thread, copper will cement precious metals and mercury. I'm probably wrong, but as I recall, and without doing further research, mercury precipitates can show as black residue. Be careful with it until you're sure.

Dave
 

spoke27

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Ty Dave, Göran And Butcher.. AR was Cold and I Heated it is mostly Dissolved.. But sollition not give me colors with SnCl2.. it is not Mercury
White salt heated in beaker stay..
I must be learn copper cementation.. readed all Kurtak topics
I was't use Air
 

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