Best metal to cement copper?

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Alabama938

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Feb 13, 2021
Messages
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Is it iron for sure, what about tin? If the answer is definitely iron then what is the best version of it… I’ve seen a lot of angle iron mentioned, What about Unseasoned cast-iron? Steel wool is less than 2% carbon from what I can find, can’t seem to locate pure iron wire. Is there a carbon amount to stay below in a steel wire product?
 
Most common steel will cement copper, you can use railroad iron, rebar for concrete, most steel from a computer case, structural steel used in building (angle iron), the A-frame of your truck or car, basically most any steel with high iron content, although if the steel or iron was covered in rust, oils, grease, a pickling scale. or paint that would be more of a problem than any carbon or other metals in the steel, and the surface would need to be cleaned or removed, stainless steels or metals with high nickel or chromium should, of course, should be avoided for their resistants to acids as well as the toxicity of the solutions...

I do not understand the question of tin and iron.
Tin and iron are two completely different metals easy to identify.
If you are thinking food cans that's another subject, they used to be tin coated steel, nowadays they often have other coatings to protect the food products.
 
I was asking about tin because it’s above iron (closer to copper) on the metal reactivity chart. Based on that I assumed that dropping copper on iron would drop some tin as well, especially in a chloride heavy solution.

Probably a non issue if using nitric for base metals because of the metastannic formation, but an HCl path should leave some tin chlorides in solution that would decrease purity of the copper cement right?
 
Well, our intent here is not the refining of the copper, only to remove or to recover copper from the solution, as well as many of the other toxic metal ions from the solution being treated as waste, in a preparation step to make the solution safer for disposal.



Tin would reduce Copper II chloride forming copper I chloride (basically leaving copper in solution and some as a salt of copper chloride) in a mess of toxic metal solution (most likely almost impossible to filter because of the hydrolyzed tin in solution...

Iron can reduce many metals from solution as well as the copper, this is one reason why we use iron to remove the copper and many other toxic metal ions, many of the toxic or dangerous metals are also reduced along with the copper, and removed from the solution, so the solution can go for further waste treatment process...
 
Thanks for the detailed response…

I knew it couldn’t be as simple as just a chart.

I was curious because I thought refining or at least recovering, cleaning, and melting the cement copper could be a fun. I found the 911metalurgist article that delved into the subject, including parameters for electrolysis of the recovered metal for high grade powder. But they made no mention of why tin would be a poor choice for cementing copper
 
How do i clean the copper cement that i obtain by sacrificing iron? I was adviced by someone to use dilute HCL solution and wash the cement copper with it to clean it.By cleaning i mean removing leftover iron in copper cement.Also whats the best way to process this further to sell this copper? Like should i dry this and melt it in copper billets? or get it tested for contents and sell it as it is?
 
You'll almost inevitably waste more time money and effort melting copper than it's worth. Copper isn't an easy metal to melt on a large scale. You'd need an operation set up exclusively to deal with refining and melting copper.

In order to sell sponge it would need to be of very high purity and people that need that type of thing is a niche market making it difficult to sell. They will most likely stick with their current supplier. I remember Harold posting about having 55 gallon drums of copper sponge that no one would buy. Some here will save the sponge for other operations like possibly dropping PMs out of solutions or even for more waste processing. The extremely high surface area of sponge makes some things go very fast. This way you can also keep the copper for use in the processing stream and use it over and over. There are probably other things you can use it for that I'm not familiar with. For the most part I think you'd be better served just tossing it.

ETA: you can certainly collect and melt copper for academic purposes but you probably shouldn't expect to make a profit from it.
 
PURE copper from electrolysis is quite expensive. So if you purify and then not remelt it, it can be profitable. But I do not know how often this is really purchased.
Check:
copper powder | eBay
Brand name copper powder is even far more expensive. But it has to be very pure and should be sieved.
You could use a copper cell, just like the silver cell often described here in this forum, to purify.
Btw: Once I did try to use fine copper powder to precipitate gold. But that was a bad idea, because of the large surface, the tiny copper balls offered to the solution. I ended up with a clump of gold-plated copper and had to do it all again...
So for that purpose it did not serve well.
 
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I was really trying to find out how the get the copper out of either AP leach or copper nitrate from inquarting. A clean ish method to pull out copper, just to see if I could recover it. I’ve since learned that waste management sucks so I spend my effort more wisely
 
Copper 2 chloride is a beast to refine, involving 1000• and then electrolysis (edit: for only 50% yield) and as such is much cheaper and easier to just drop with iron.

Copper 2 Nitrate, on the other hand, can be boiled dry at a much lower temp and leave you with copper 2 oxide (recover the nitric acid). To go further, either hydrogen reduction or (gasp!) carbon reduction. There’s uses for CuO though
 
PH adjustments by adding a base (not recommended) or diluting the solution with water. When you dilute CuCl2 with water it will precipitate solid CuCl. The color of the solution will shift from green to blue. The CuCl is slightly soluble in water at normal ambient temperatures. By this point most base metal has precipitated as oxides or weak chlorides. You can remove the blue solution to another container and replace the solution with fresh water. Tap water is fine. Add any type of bare soft steel. I have begun using rebar as it's general found in scrap or cheap to buy. This prevents premature deterioration of the sacrificial metal. Once the copper is removed from the solution, move the spent solution to another container and neutralize the small amount of acid to a PH near 7 and allow the solution to settle until it is clear. The solution is mostly salt water (sodium chloride for chloride solutions) and can be discarded in the storm drain. It should be no more toxic than the salt applied to the roads to melt ice and snow. During this time the water added to the CuCl should have dissolved enough copper to repeat until all the solids have been converted to elemental copper. It generates a lot of liquid waste and takes more time than a more aggressive approach but it saves on resources and the final products are much cleaner.
 
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