deplating silver from silverplated items

[watcher6880]

Where can you buy sodium persulfate? I checked refiningchemicals.com and couldn't find any. Also would the average Joe be able to get this without complicated channels like purchasing nitric acid?

 

[butcher]

Look for supplies in etching circuit boards.
http://www.circuitspecialists.com/4101-1kg.html

http://www.ebay.co.uk/sch/i.html?_nkw=persulphate&_sacat=0&LH_PrefLoc=2&_dmpt=UK_BOI_Medical_Lab_Equipment_Lab_Supplies_ET&_odkw=persulphate&_osacat=0&_trksid=p3286.c0.m270.l1313

 

[watcher6880]

Just wondering step for step how this process works... I have been checking out the pics but seem to be getting confusion from them. The sodium persulfate comes in crystal form if I am correct(?) What needs to be added to this to make the solution? Sorry I am not very knowledgable of the reverse electroplating process as I am familiar with the AR and Silver Nitrate process.

 

[watcher6880]

Anyone?

 

[lazersteve]

I've used the sodium persulfate etch to dissolve the copper out of some finger boards.

It tells the proper mix with water right on the side of the jug.

It turns out it's slow for etching copper and expensive to boot, so now I have a gallon jug of the crystals and no use for them.

I've never tried using it as the electrolyte in a silver stripping cell.

Steve

 

[Geo]

can you substitute dilute sulfuric acid to make the copper sulfate electrolyte?

 

[watcher6880]

I wondered that Geo.

 

[Goldfinger4]

Yes you can use simple battery acid. The electrolysis will dilute copper and silver.
The conductivity of the electrolyte will rise until it is saturated with copper and silver ions.
Sodium persulfate is used to etch circuit boards (without electrolysis).

 

[Pally]

Hello from Canada............
I have a jar of suphuric acid (started out as two gallons) and have been blowing the plated gold off of items i picked up here and there......
I also have a great mess of silver plated items to strip......
Do you think that mere copper sulphate salts desolved in distilled water is sufficient for electrolyte?
Or would you reccomend the persuphate?
If you have any idea how to get the gold out of my solution id like to hear it too....thanks

 

[nickvc]

Pally sulphuric acid can't dissolve gold on it's own, if you use concentrated sulphuric and build a striiping cell then you can dissolve it but only for a short period of time as perasulphuric acid forms by the anode but converts back to sulphuric as it moves away dropping the gold as a black powder.
If you have a sludge in the bottom of your container it's your gold.

 

[Harold_V]

What Nick said. Be advised, because the gold that is recovered is very finely divided, it won't be colored like you expect. The black sludge you see is the gold, albeit not really pure. You must wash, dissolve, filter and precipitate the gold, then wash properly before you can consider it pure, and even then it may require a second refining. All depends on your objective.

Harold

 

[Pally]

Lots of gold flakes and micro particles can be seen floating in the acid....
These i filtered out and all the bottom sludge i have soaking in the empty glass cell jar......
I plan to settle it out anf pour off the water as much as possible, then dry the rest up.
when it turns into dry material could mercury pick up the gold out of it?PS.

Ps i am going to start deplating the silver items as suggested with battery acid...the same stuff i blew the gold off with....
I plan to use it because it is already blue with copper contamination .....
Should i mix 50/50 with distilled water? or should suphuric battery solution be ued full strength?
(i have new electrolyte from the dodge dealers...)
if using new electrolyte should i run some copper plate then try the silver after the acid goes blue green?

 

[Harold_V]

when it turns into dry material could mercury pick up the gold out of it?PS.

Why on earth would you want to use mercury? That makes NO sense at all. It also makes no sense drying the material, unless you intend to incinerate. What purpose would that fulfill?
If you don't understand what you've been told, please do yourself a favor and stop processing. Read the forum and Hoke's book, until you understand what you should be doing, and why. You'll be glad you did when the light comes on.

Harold

PS--
Mercury has NO PLACE in refining.

None!

There isn't one reason why you should need mercury.

Please read the forum on the sulfuric stripping cell. One does NOT use battery acid, for it is too dilute. It can be used after evaporation, however. It's all on the forum.

 

[tek4g63]

Has anyone else tried this using the diluted sulfuric acid? I have about 10lbs of 4X plated silver ware that I would really like to try this with. I was hoping that someone much smarter than myself had mastered this process.

Thank you for any and all input.

Thad

 

[Tankman]

Can this method be used on larger industrial type silver plated pins?

 

[etack]

You mean like these? these came from 3phase connectors and had two long gold pins in them 8) .

if they are all cooper use them to cement your silver. If you look for silver plate when your out only buy silver over copper so you can get the silver back that way. the other silver plate you can throw into old Ap and have it work on it that way. There is no cheap what to strip silver or it would be bought more frequently as silver bearing scrap.

Eric

 

[Tankman]

You mean like these? these came from 3phase connectors and had two long gold pins in them 8) .



Yes, very similar to those. They are pins from Compaq/HP bus bars and are copper underneath. Thank you for the advice on using them for cementing silver. 8)

 

[solar_plasma]

Just for the completeness, CuSO4 instead of copper dissolved in sodium persulfate works. Where the CuSO4 comes from doesn't matter.

Is there anybody who was able to optimize the process? I am running it since some days, after some testing, now with about 8V at 10A. I get about 20g silver per day of active process from 24 pieces with about 100g silver plating on about 1 kg of material. This seems to be a bit slow to me.

 

[butcher]

solar_plasma,
I tried an experiment like what you are doing, trying to remove the silver from plated silver spoons and forks, I tried a couple of different electrolytes, copper sulfate seemed to work the best and was the safest, (I also had plenty of copper sulfate from other processes), I did not use or have a membrane bag (so your results may or may not prove different than mine), I could remove the silver along with some copper and other base metals from the plated articles using this method, which gave me a mixture of silver and copper as the results, with these fluffy powders I had to use other acid treatments to dissolve the copper from the silver, to reclaim the silver, the only benefit I seen was I was able to remove the silver plate without dissolving all of the metals in the spoons and forks, but in the end I cannot say I made any progress, as the amount of silver recovered for all of the time trouble and acids and other chemicals I used, probably cost me more than anything I gained in silver, so basically unless I learn something different about this process I do not think I would try it again, I am interested in seeing how you do with your experiment, and seeing if your results are different than mine were, of if you can make it work better than I could.

 

[solar_plasma]

I did not use or have a membrane bag

With membrane I had a bad conductivity, so I dropped it again for this first experiment. BUT with membrane the copper crystals got very heavy and would not fall apart, when removing the cathode. Quite interesting. I use my experiences with this first sample to find out how I will construct my next cell. I am very optimistic.

Small contaminations of the silver with coppertraces can obviosly be treated by the dissolved AgSO4. I just remove the electrodes for a night and let the silver cement on the copper traces.

I think you are right, this cell is nothing to earn money with, not if you count the hours spent maintaining it