Copper and silver cell

[Jimbriese]

Hey guys I am working on setting up a copper and silver cells. Starting off small and have got the size containers and everything needed gathered up.
Started to make the electrolyte for getting my copper cell going. I had some heavy silver plated copper that I decided would work well for this as it would give me the cement silver to use for the silver cell next. The total weight was 3269 grams. I then start dissolving them with nitric acid removing and replacing to get most of the silver off the copper. Then dropped in the cleanest copper to finish using up the nitric acid and cement out the silver. At this time the reaction was going great but was out of time so left it to finish and left for work.
Got home and all looked good bright blue with cement silver. So I weighed what was left at this point and I had 174g of copper in solution and cement silver. Need between 4-6 liters for the copper cell and then some extra for top offs I decided I was a little short so added the copper bar back and the rest of my nitric acid I had on hand. Got everything going great stir bar mixing and left it on low heat as it was a little cool where it’s at. Went to bed woke up and my solution went from the bright deep blue to a dark green color. And no more reaction. At this point I have removed from heat and pulled out the remaining copper and stir bar to let settle.
My question is about the color I believe it’s due to being to concentrated and needs some water added. Would it be better to add the water before or after removing the silver for the best results on the silver.

 

[Jimbriese]

Update I FFFFed up and had a brain fart. I had moved my AP with bubbler going into my fume hood due to some stray cats knocking stuff over in my outdoor covered area. I didn’t even think about it being in there. So the first part of this was done at same height and went good but second part when I added heat and stirring it raised my beaker so the bottom was about the same height as the top of the AP. And now I have a mess as I’m not sure what I have at the moment. Going to start researching and see what I can find. Any help would be appreciated. So far I have vacuumed filtered the solution and removed a very light grayish solid that is paste like when I transferred to a smaller beaker to start rinsing and added a little water the picture is less than 5 minutes of settling after a good stir. The other picture is a small sample of the filtered solution and of the solids before rinsing.

 

[Yggdrasil]

Update I FFFFed up and had a brain fart. I had moved my AP with bubbler going into my fume hood due to some stray cats knocking stuff over in my outdoor covered area. I didn’t even think about it being in there. So the first part of this was done at same height and went good but second part when I added heat and stirring it raised my beaker so the bottom was about the same height as the top of the AP. And now I have a mess as I’m not sure what I have at the moment. Going to start researching and see what I can find. Any help would be appreciated. So far I have vacuumed filtered the solution and removed a very light grayish solid that is paste like when I transferred to a smaller beaker to start rinsing and added a little water the picture is less than 5 minutes of settling after a good stir. The other picture is a small sample of the filtered solution and of the solids before rinsing. View attachment 66895View attachment 66896View attachment 66897View attachment 66898

I don't quite understand what you describes with you beakers.
Anyway AP and Nitric, I'd suspect Metastannic acid.

 

[nickvc]

I believe the electrolyte for a copper cell is copper sulphate so I’m unsure why you dissolved your copper in nitric.

 

[Jimbriese]

I don't quite understand what you describes with you beakers.
Anyway AP and Nitric, I'd suspect Metastannic acid.

So this is how it was the two beaker against the wall are some magnetic gold plated pins and some transistor and ic chips that have gold plating on the legs and ground pads I’m using some excess AP to consume the base metals. Nothing was done with them except the bubbler was running.
The silver/copper nitrate was on the hot plate/stirrer on low heat with a small cone from stirring to finish using up the nitric and cement out all the silver. I’m guessing the vortex cone from stirring pulled some of the fumes from the AP into the nitric? There was no mixing of the two solutions and the pipe above the AP is the exhaust for the fumes hood. And all are covered only sizable opening is the pour spouts. They were about 12 inches apart as seen in the attached pic

 

[Jimbriese]

I believe the electrolyte for a copper cell is copper sulphate so I’m unsure why you dissolved your copper in nitric.

Take the copper nitrate add sulfuric acid to make copper sulfate and nitric acid. Then distill off the nitric. Your left with copper sulfate for the copper cell and diluted nitric acid

 

[Jimbriese]

I don't quite understand what you describes with you beakers.
Anyway AP and Nitric, I'd suspect Metastannic acid.

If there was tin on the copper with the silver to cause metastannic acid. Would I still be able to convert the copper nitrate to copper sulfate and nitric acid? It’s already filtered once and came out clear of debris. Used a 410 filter paper under a coffee filter. The coffee filter catches the bulk and the 410 stops the fines. And there wasn’t much for fines in the filter paper most was trapped in coffee filter

 

[Yggdrasil]

If there was tin on the copper with the silver to cause metastannic acid. Would I still be able to convert the copper nitrate to copper sulfate and nitric acid? It’s already filtered once and came out clear of debris. Used a 410 filter paper under a coffee filter. The coffee filter catches the bulk and the 410 stops the fines. And there wasn’t much for fines in the filter paper most was trapped in coffee filter

Well it will convert.
But you still have the Metastannic to deal with.
Let it settle fore some days and then carefully siphon off the clear liquid.
Do this a few times until you deem it good enough.
Let the rest go to the waste treatment.

 

[Jimbriese]

Well it will convert.
But you still have the Metastannic to deal with.
Let it settle fore some days and then carefully siphon off the clear liquid.
Do this a few times until you deem it good enough.
Let the rest go to the waste treatment.

Sorry not sure what you’re saying. Are you saying to convert to copper sulfate then settle and collect the clear liquid.
If so that would make the clear liquid the dilute nitric ?

 

[Yggdrasil]

Sorry not sure what you’re saying. Are you saying to convert to copper sulfate then settle and collect the clear liquid.
If so that would make the clear liquid the dilute nitric ?

It do not matter much, but I would clean it first, then convert to Sulfate.

 

[Jimbriese]

So still not sure what caused the copper nitrate to be the original dark green but this is the results of converting to copper sulfate. Nice crystal clear blue solution ready to distill off the nitric acid.

Here is what was filtered out this is what I thought was the silver plating. I transferred it to the graduated cylinder then capped and shook up good and let settle. It’s about 52ml worth the very top 2ml is very fine almost white the rest appears to be a light grayish tan color. What would you guys suggest doing with the solids to try and figure out what it is. And is it possible this is just cement silver that was finely broken up from the stirring during the cementing out?

 

[Yggdrasil]

So still not sure what caused the copper nitrate to be the original dark green but this is the results of converting to copper sulfate. Nice crystal clear blue solution ready to distill off the nitric acid.
View attachment 66901
Here is what was filtered out this is what I thought was the silver plating. I transferred it to the graduated cylinder then capped and shook up good and let settle. It’s about 52ml worth the very top 2ml is very fine almost white the rest appears to be a light grayish tan color. What would you guys suggest doing with the solids to try and figure out what it is. And is it possible this is just cement silver that was finely broken up from the stirring during the cementing out?

View attachment 66902

Has it darkened?
What happens if you add a bit of Salt?

 

[Jimbriese]

Has it darkened?
What happens if you add a bit of Salt?

I did a sample in a test tube added some saturated salt water and nothing precipitated. I added the sulfuric acid about 12 hours before the picture was taken and it is same color as when first completed. I first added 200 ml of sulfuric tested and showed it needed more added a total of 300ml sulfuric before test showed there was enough.

 

[Yggdrasil]

I did a sample in a test tube added some saturated salt water and nothing precipitated. I added the sulfuric acid about 12 hours before the picture was taken and it is same color as when first completed. I first added 200 ml of sulfuric tested and showed it needed more added a total of 300ml sulfuric before test showed there was enough.

Good, then we can rule out Silver.
Most likely Metastannic then.

 

[Jimbriese]

So I think I figured it out just found the third center pivot that has been untouched and it appears there is two coatings on those pieces the outside no contact area appear to be some type of galvanized coating and the inside where it contacts the switch blade is silver

 

[4metals]

I think your original feedstock can be much more than simply copper over plated with Silver. The addition of unknown metals is what I think is gumming up the process. You are not making copper sulfate by dissolving electroplated copper in sulfuric acid. This would be the preferred method. There is a video in our video section by NurdRage on distilling the nitric and recovering the copper metal. Is this the process you used or was your process a shortcut of some sort?

 

[Jimbriese]

Good, then we can rule out Silver.
Most likely Metastannic then.

So I guess the silver mixed with the metastannic made it filter better then the first time I ran into metastannic acid it took 3 days to filter 2 L this took less than an hour for 2.4L and came out crystal clear in one pass thru the filter

 

[anarxi]

So still not sure what caused the copper nitrate to be the original dark green but this is the results of converting to copper sulfate. Nice crystal clear blue solution ready to distill off the nitric acid.
View attachment 66901
Here is what was filtered out this is what I thought was the silver plating. I transferred it to the graduated cylinder then capped and shook up good and let settle. It’s about 52ml worth the very top 2ml is very fine almost white the rest appears to be a light grayish tan color. What would you guys suggest doing with the solids to try and figure out what it is. And is it possible this is just cement silver that was finely broken up from the stirring during the cementing out?

View attachment 66902

most likely the base was bronze.
its color is very similar to copper.
Even the experienced eye of a metal collector will not always see the difference.

Bronze contains tin.
your sediment is a mixture of tin, silver and salts.
in metastanoic acid.
if you dissolved everything, did you pour salt water into the blue solution?
silver in it.

but there is very little of it.
if the parts were massive, coated with silver, then there will be no more than 0.5% of the total mass.

 

[anarxi]

So I guess the silver mixed with the metastannic made it filter better then the first time I ran into metastannic acid it took 3 days to filter 2 L this took less than an hour for 2.4L and came out crystal clear in one pass thru the filter

So I guess the silver mixed with the metastannic made it filter better then the first time I ran into metastannic acid it took 3 days to filter 2 L this took less than an hour for 2.4L and came out crystal clear in one pass thru the filter

I make silver through chloride.
I filter very roughly, add salt water,
it dilutes the solution.
I've been waiting for an hour.
then I drain the water along with metastanic acid and work only with chloride.