Stock Pot Copper Won't Cement

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Joined
Jan 16, 2015
Messages
41
Location
Los Angeles County
I have two stock pots, a 3 gallon and a 5 gallon, and both have the same waste solutions from doing the same refining processes of the same source materials, yet only the 3 gallon cements out copper, the 5 gallon yields nothing.

stock pots 1.JPG

Both pots have a lot of copper, not only from the gold plated pins and connectors I had processed but also from the scrap copper I had added to see if I could get any gold out of the solutions which I may have missed. The point is, I know there's a lot of copper in the 5 gallon pot, so it's not a question of nothing cementing out because there isn't anything there in the first place.

This next image of my 3 gallon pot shows the copper cemented out on my rock hammer, notice that the hammer is practically eaten all the way through the handle part. When I first added the hammer, the reaction was immediate, thick amounts of copper cemented out, enough so that after a day I knocked off a 1/4" thick layer of it.

stock pots 2.JPG

The next image of the 5 gallon pot just shows that no copper cements, the "mexico" on the rebar was submerged for days and it's still void of copper.

stock pots 3.JPG

There's only one difference that I can think of between the two pots, the 3 gallon is older, it had been sitting out in the sun evaporating and concentrating for a month before I added the iron, it went from about 2-1/2 gallons down to its present volume of about 1 gallon. It's deceptive but there's not more than 3" of solution in the bucket.

Maybe the solution in the 5 gallon pot is too dilute, could the answer be as simple as that, or is there another explanation? Any suggestions as to what I can try?
 
Maybe the rebar has a co as ting to resist corrosion?

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Switch the rebar to the smaller bucket and the hammer to the larger. See if the problem moves, then it is some corrosion inhibitor on the rebar that is the problem.

Sometime when I have a hard time to get the cementing going I just add a dab of HCl to the solution to create a more pristine surface for the copper to attack ... or I just add some other iron to it. I prefer to start with steel from inside old computer casings, no paint, just the gray phosfate surface treatment. When most of the copper is out I switch to thicker iron so I get a relatively clean copper powder without a lot of small iron pieces.

Göran
 
g_axelsson said:
Switch the rebar to the smaller bucket and the hammer to the larger. See if the problem moves, then it is some corrosion inhibitor on the rebar that is the problem.

Sometime when I have a hard time to get the cementing going I just add a dab of HCl to the solution to create a more pristine surface for the copper to attack ... or I just add some other iron to it. I prefer to start with steel from inside old computer casings, no paint, just the gray phosfate surface treatment. When most of the copper is out I switch to thicker iron so I get a relatively clean copper powder without a lot of small iron pieces.

Göran

Once I saw that the rebar did nothing, the first thing I did was to try the hammer since I knew it worked, same result though, nothing.

I also tried a steel chisel, you can see it sticking out of the solution behind the rebar, and also tried an old cast iron block plan, again though, nothing.

One other thing I tried which is similar to what you're suggesting, I took 20ml of the solution in a beaker and added 20ml of fresh hydrochloric, to this I dangled an old rusted 1/2-13 nut. Still got no copper to cement, the only thing I did was to clean the rust off the nut and shine it up a little.
 
g_axelsson said:
Switch the rebar to the smaller bucket and the hammer to the larger. See if the problem moves, then it is some corrosion inhibitor on the rebar that is the problem.

Sound advice there.
 
PH should be about 2.5

4Metals wrote an excellent post on the subject.

https://r.tapatalk.com/shareLink?url=http%3A%2F%2Fwww%2Egoldrefiningforum%2Ecom%2FphpBB3%2Fviewtopic%2Ephp%3Ft%3D1300&share_tid=1300&share_fid=1462545&share_type=t

Sent from my SM-G950U using Tapatalk

 
rickzeien said:
PH should be about 2.5

4Metals wrote an excellent post on the subject.

https://r.tapatalk.com/shareLink?url=http%3A%2F%2Fwww%2Egoldrefiningforum%2Ecom%2FphpBB3%2Fviewtopic%2Ephp%3Ft%3D1300&share_tid=1300&share_fid=1462545&share_type=t

Sent from my SM-G950U using Tapatalk

This is excellent, this is what I'll do, thanks.
 
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