# Method for Recovering Silver From Silver Plated Scrap - VIDEO



## kadriver (Jan 9, 2019)

We found a silver plated dish 10.5 inche diameter that had a thick coating of silver plate.

I made a video and dissolved the entire plate using 900ml of concentrated nitric acid.

Then I filtered and precipitated the silver chloride and converted to pure silver metal with lye and sugar.

I ended up with a 4.6% yield of pure silver, 15.2 grams from the 324.5 gram silver plated plate.

Here is a link to the video:

https://youtu.be/ilu3yOrHH6s

This is my first attempt with silver plate and I decided to do it based on the results of the tests on the silver plated item. It seemed like much more silver plate than I am used to seeing.

Is this typical for the amount of silver that can be expected from this type of silver plated scrap?

Thank you,
kadriver


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## nickvc (Jan 9, 2019)

When the silver price was much higher there were several people I know of who were refining silver plated material, they were using a very hot mixture of sulphuric and nitric I believe as it is more selective but the problem of course were the fumes, they were downright dangerous it was something I decided that really wasn’t for me despite the decent returns available, personally I think dissolving all the base metals to recover the silver will be a losing proposition for most silver plated material, I fear no one has yet found a way to make recovery a profitable enterprise.


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## goldsilverpro (Jan 9, 2019)

nickvc said:


> When the silver price was much higher there were several people I know of who were refining silver plated material, they were using a very hot mixture of sulphuric and nitric I believe as it is more selective but the problem of course were the fumes, they were downright dangerous it was something I decided that really wasn’t for me despite the decent returns available, personally I think dissolving all the base metals to recover the silver will be a losing proposition for most silver plated material, I fear no one has yet found a way to make recovery a profitable enterprise.


I agree with Nick. Very high yield.I think you hit a 1 out of a 1000 piece


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## anachronism (Jan 9, 2019)

Agreed with Nick and Chris. That's one seriously lucky piece to get that much silver. Now everyone on Youtube will think it all yields like that.

Dissolving the whole piece is great for the video (I like the setup by the way) however it's not practical for volume. 

Jon


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## archeonist (Jan 9, 2019)

The only way I can think of is mechanically removing the silver plate. The experiment that I am going to do is sand blasting silverplate items. You'll end up with a mixture of dust that contains sand and metal particles wich are easy to seperate. I think this method would be fairly quick and low in costs as you don't need a lot of nitric. Still haven't got time to work this out but soon I will.


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## speed (Jan 9, 2019)

Electrolysis in salt water is a good method no? Never done it but have seen people doing it. Silver comes off and settles to bottom of the electrolyte.

I've been collecting together a batch to have a go myself. I just buy it at brass scrap price usually so can't really loose. Yield per weight isn't really a good way of doing it as it's surface area that actually matters ofcourse. Not easy to quantify but good to bare that in mind when buying.


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## archeonist (Jan 9, 2019)

speed said:


> Electrolysis in salt water is a good method no? Never done it but have seen people doing it. Silver comes off and settles to bottom of the electrolyte.
> 
> I've been collecting together a batch to have a go myself. I just buy it at brass scrap price usually so can't really loose. Yield per weight isn't really a good way of doing it as it's surface area that actually matters ofcourse. Not easy to quantify but good to bare that in mind when buying.



No it is not a good method, it is very time consuming.


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## speed (Jan 10, 2019)

Why?


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## ION 47 (Jan 11, 2019)

speed said:


> Why?



Electrolysis in a solution of sodium sulfite is absolutely safe for health, the silver is deposited as a porridge at the cathode of stainless steel. Аnd brass or copper base remains intact. I tried to shoot silver with silver-plated coaxial radio frequency cable and plates from radio equipment. It's good. I don't know any other safe way.


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## goldsilverpro (Jan 11, 2019)

archeonist said:


> The only way I can think of is mechanically removing the silver plate. The experiment that I am going to do is sand blasting silverplate items. You'll end up with a mixture of dust that contains sand and metal particles wich are easy to seperate. I think this method would be fairly quick and low in costs as you don't need a lot of nitric. Still haven't got time to work this out but soon I will.


Instead of sandblasting, try shot peening. It stretches the plate laterally, breaks the plating bond, and the plating falls off. I once experimented with various base metal/plating combinations and everything worked. I'm thinking I tried both glass bead and steel shot and they both worked.


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## archeonist (Jan 11, 2019)

Why it is time consuming is because it just takes a lot of time doing this piece bij piece. Let's say if you'ld run a spoon for instance, you first do one half and wait, then you do the other half and wait till all the sliver has come off. That takes a lot of time to do this piece by piece. Silver is just not worth it unless you are doing it for fun. I think sand blasting will do the job pretty quick. Later this year I will make an attempt on this.


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## ION 47 (Jan 12, 2019)

I will continue to defend my point of view. I believe that abrasive removal of silver is not a very good method, because with the help of silver you will inevitably remove part of the base (copper, brass), and later they will have to get rid of. The method I propose does not dissolve the base metal. You don't need to spend a lot of time. You only need to immerse the silver plated item into solution (Na2SO3. 50 g / l + H2O), turn on the power, set the voltage to 1.5 V + _ 0.5 V, and after a while to collect silver from the cathode. http://www.findpatent.ru/patent/246/2467082.html, https://www.youtube.com/watch?v=KExnYmnmElo


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## Owltech (Jan 12, 2019)

ION 47 said:


> I will continue to defend my point of view. I believe that abrasive removal of silver is not a very good method, because with the help of silver you will inevitably remove part of the base (copper, brass), and later they will have to get rid of. The method I propose does not dissolve the base metal. You don't need to spend a lot of time. You only need to immerse the silver plated item into solution (Na2SO3. 50 g / l + H2O), turn on the power, set the voltage to 1.5 V + _ 0.5 V, and after a while to collect silver from the cathode. http://www.findpatent.ru/patent/246/2467082.html, https://www.youtube.com/watch?v=KExnYmnmElo



Tried the method from your video and it works. I had to make the sulphite from SMB and NaOH, but it worked (@ 3v).


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## kurtak (Jan 13, 2019)

First off I need to say I have never tried to recover silver from silver plated items "other then" silver plated buss bars in which case the silver plating is recovered when using the bus bars to cement silver from silver nitrate solutions - the bus bars are first tested with a drop of HCl to make sure the plating is in fact silver plating & not tin plating

The reason I have never tried to mess with recovering silver plating from items other then bus bars is (1) when I lived in Wisconsin there was a company that would buy my silver plated for 20 - 25 cents a pound over what scrap yards paid for bass (if the plating was on brass) or 20 - 25 cents a pound (over) for number 1 copper (if the plating was on copper) --- &/or (2) as Hokes says in her book - " the silver - if worth while" - & I just don't see chasing silver plating as being worth while out side of "maybe" one exception (which will be at the end of this post)



archeonist said:


> The only way I can think of is mechanically removing the silver plate. The experiment that I am going to do is sand blasting silverplate items. You'll end up with a mixture of dust that contains sand and metal particles wich are easy to seperate. I think this method would be fairly quick and low in costs as you don't need a lot of nitric. Still haven't got time to work this out but soon I will.



Per the under lined - how do you intend to recover the silver from sand ?



> Electrolysis in a solution of sodium sulfite is absolutely safe for health, the silver is deposited as a porridge at the cathode of stainless steel. Аnd brass or copper base remains intact. I tried to shoot silver with silver-plated coaxial radio frequency cable and plates from radio equipment. It's good. I don't know any other safe way.



You don't need "any" chemicals for an electrolytic cell - just "tap" water - it doesn't get any safer then that

:arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=50&t=16591

The problem being that you still can't run it in any "volume" that would make the recovery "worth while" in my opinion

On the other hand - IF (big IF) I where ever to chase after the recovery of silver plating it would be cyanide leaching & that is because you could actually set up to run it in volume 


Cyanide will leach/dissolve silver plating just as it does gold plating


The silver can then be recovered from the solution by cementing with zinc powder (it takes about 1/2 oz of zinc to recover 1 ozt silver) or recovered with activated carbon - or with an electrolytic winning cell - & if it where me I would use the winning cell & that's because after winning the silver back from the leach the leach can be reused again (to a point & with some adjustment made to the starting leach) & when the leach reaches a point of not reusing it - it (the cyanide) can be destroyed for safe disposal by reversing the polarity of the cell & running it through the cell


For more details read what Deano & Jon have posted here on the forum about cyanide leach for gold plating - recovering the gold with the winning cell & then destroying the cyanide (in the same cell) when the leach is spent


The process is &/or will work the same with silver plating


The one thing I am not sure of is that there "may" be a time difference in the leaching of silver compared to that of gold - silver "might" take a little more time --- maybe Deano or Jon could chime in on that (or for that mater other members like 4metals, GSP, Lou, etc.)

What I do know - is that if I where ever to chase after the recovery of silver plating - cyanide leaching would be the "only" way I would try - & that is because it is about the only way I can see to do it in any kind of volume - which from what I can see - volume is the only way to chase silver plating & have it be "worth while"

Kurt


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## archeonist (Jan 13, 2019)

Silver can be separated from sand by extraction with nitric.


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## nickvc (Jan 14, 2019)

Kurt the one problem with using cyanide is that to make it selective for only silver I believe like with gold you have to run it very weak to avoid to much base metals been dissolved, so to run volumes you would need huge volumes of solutions, the other problem would be the mixed base metals underneath the silver plating which will make balancing the leach to be selective even more difficult, perhaps GSP has the best idea and peening the silver plate off may be the way for small operators.


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## nickvc (Jan 14, 2019)

archeonist said:


> Silver can be separated from sand by extraction with nitric.



You could end up with huge volumes of waste doing this simply because to filter the silver solution from the sand will require a lot of rinses with distilled water to avoid converting the silver to chlorides and thus trapping it in the sand.


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## speed (Jan 14, 2019)

I don't see why on a 'medium scale' electro-deplating wouldnt be viable.. you would have to have a plating 'tumbler' ofcourse as connecting each item up to a busbar individually would be more time than its worth but if you could just chuck a few kg of cutlery or shredded plate items into a basket at a time and just let it tumble until its done it seems like very little effot other than the inital investment. Its maybe not something for a large scale refiner but for a hobbyist looking to make a few $ in thier spare time I think it could be a good project. I know the material is out there and essentially pretty worthless other than its scrap value. 

Correct me if I'm wrong but a solution of tap water and plain old sodium chloride salt would be a sutible electrolyte. Does it need to be sodium sulfite?


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## kurtak (Jan 14, 2019)

Nick --- thanks for the reply - I got up later then usual this morning so don't have time to reply before going to work & yes I would like to hear from some of the other pros on this



> Silver can be separated from sand by extraction with nitric.





> You could end up with huge volumes of waste doing this simply because to filter the silver solution from the sand will require a lot of rinses with distilled water to avoid converting the silver to chlorides and thus trapping it in the sand.



Filtering is not the only problem I see here - again I don't have time to post this morning



> Correct me if I'm wrong but a solution of tap water and plain old sodium chloride salt would be a sutible electrolyte. Does it need to be sodium sulfite?



speed --- did you read the link I provided --- you don't need to add anything to the water - it works with just plain "tap water" 


Kurt


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## Shark (Jan 14, 2019)

Running plated items in the H2O cell isn't that big of a problem, and works fairly well on smaller items such as flatware. When using a smallish cell, (mine is about 2 gallons), you may need to stop and let it settle occasionally to avoid problems but that won't occur very often. Before we moved, all I needed was just plain tap (city) water. At our new place the city water will work, but it is much better water quality (spring water) and is very slow to get started in the cell. I have added 2 teaspoons of table salt to get it started, but prefer to use just the water, as I often have the time, which is very minimal, to get started. I can do 20 to 30 pieces a day, and it would work better with a larger volume, taller cell. The recovered material is voluminous and the taller cell would give me more time to run material between clean outs. I only get this stuff occasionally, and at times it will be whole sets of flatware, so this method works pretty good for me. I have tried sulfamic acid in a cell, and was not happy with the results so far. It eats a lot base metals and needs constant watching to avoid much of the base metals. Both cells would leave small amounts of silver behind and the sulfamic ate most base metals quick once it got started on them. I would love to try GSP's idea of shot peening, I used a big peening machine years ago to clean aluminum and think based on that experience it would would work rather well.


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## ION 47 (Jan 14, 2019)

speed said:


> I don't see why on a 'medium scale' electro-deplating wouldnt be viable.. you would have to have a plating 'tumbler' ofcourse as connecting each item up to a busbar individually would be more time than its worth but if you could just chuck a few kg of cutlery or shredded plate items into a basket at a time and just let it tumble until its done it seems like very little effot other than the inital investment. Its maybe not something for a large scale refiner but for a hobbyist looking to make a few $ in thier spare time I think it could be a good project. I know the material is out there and essentially pretty worthless other than its scrap value.
> 
> Correct me if I'm wrong but a solution of tap water and plain old sodium chloride salt would be a sutible electrolyte. Does it need to be sodium sulfite?



Here is a process with sodium sulfite, takes little time, for 8 hours in a 50 gram Ag cell.the Basket is made of titanium mesh, the cathode is titanium plate. (Thank you, President Gorbachev, military missiles are not being built in Russia now, and we can make electrolysis cells out of titanium with our own hands).


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## ION 47 (Jan 14, 2019)

The basket can be made of chemically resistant stainless steel.


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## ION 47 (Jan 14, 2019)

Photos are not mine, but I worked, and guarantee success! silver in dry sediment is obtained 90-95%


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## Shark (Jan 14, 2019)

ION 47 said:


> Photos are not mine, but I worked, and guarantee success! silver in dry sediment is obtained 90-95%



Looks good, ION, any information on making the electrolyte?


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## ION 47 (Jan 14, 2019)

Shark said:


> ION 47 said:
> 
> 
> > Photos are not mine, but I worked, and guarantee success! silver in dry sediment is obtained 90-95%
> ...



Link to the patent: http://www.findpatent.ru/patent/246/2467082.html there is a description of the process. Electrolyte: 50-80 g of sodium sulfite per 1 liter of distilled water. The voltage on the cell is 1-3 Volts, the Amperes drop as the Ag is removed from the base.
"...A method for electrochemical extraction of silver from silver-containing conductive waste comprising anodic dissolution of silver in an aqueous solution of the complexing agent in potentiostatic mode with an anode from the feedstock and an insoluble cathode, characterized in that as a complexing agent using sodium sulfite with a concentration of 12-370 g / l, anodic dissolution is carried out at 18-50°C at an anode potential of 0.40÷0.74 V relative to the normal hydrogen electrode, the process is carried out in a closed volume in a non-aggressive slightly alkaline medium

http://www.findpatent.ru/patent/246/2467082.html
FindPatent.ru -patent search, 2012-2019"


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## kurtak (Jan 16, 2019)

nickvc said:


> archeonist said:
> 
> 
> > Silver can be separated from sand by extraction with nitric.
> ...



Filtering the silver nitrate out of the sand is not the only problem (which is going to take "A LOT" of distilled water - like 2 if not 3 or 4 times the water of the starting leach solution) 

The other problem is going to be making up the leach to be effective & at the same time not wasting nitric - in other words figuring out how much metal the sand is loaded with in order to determine the amount of nitric needed to leach the metal without wasting nitric


Sand blasting is not only going to take off the silver plating - but base metal as well - it takes "about" 4 times more acid to dissolve base metal then it takes to dissolve silver 


So how do you determine (1) how much metal is loaded in the sand - then (2) what is the ratio of silver/base metal in order to (3) determine nitric need to leach out "all" the metal - without wasting nitric


Keep in mind - that as the nitric dissolves metal it becomes less effective in dissolving the metal - to the point it will near stop dissolving metal (before the acid is used up) without heat

How are you going to heat the leach in a "bunch" of sand

With heat - you are going to have to use "extra" nitric just to make sure all the metal is leached

Without heat - your going to have to use even more acid so the acid can even work at dissolving the metal

Bottom line - your going to have to "waste" nitric to insure you get all the metal leached out

And then you still need to get "all" the silver (& base metal) nitrate washed/filtered out - "after" the sand blasting process

maybe I am wrong - but seems like a loooong way around for little return

Kurt


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## ION 47 (Jan 16, 2019)

kurtak said:


> nickvc said:
> 
> 
> > archeonist said:
> ...



You can take up peskostruy, or file, or chisel, they cut Ag. :lol: But to mechanically remove only Ag, without affecting the basics, you need to be blind, since blind people have a more developed sense of touch, and they feel the difference in the units of micron with their fingers. I don't think we should discuss this medieval technology  .


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## snoman701 (Jan 16, 2019)

Ya'll crazy.

When you sand blast you generate dust. This dust is partially the breakdown of the media, but also the media that's being removed. 

The reality of this is that you are going to have a fine, difficult to filter SiO2 particle and a particle of silver and a particle of copper and zinc and nickel...and all over, some lead, probably cadmium and lead as well.

It's all going to end up in your shopvac.

That material can then be directly melted and collected in a cone.

Yes, your coarse sand will still have silver too...so just melt it when you are done.


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## snoman701 (Jan 16, 2019)

I would add...given how much silver plate weighs in comparison to it's surface area...I think you'll have a hard time doing this profitably with an air compressor. 

I know what it cost just to run the compressor /dry and filter the air / and pay for a guy to blast. 

It's an expensive process.


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## geedigity (Jan 18, 2019)

Try a CO2 blaster. No waste. You need good ventilation, however and dry ice tends to be expensive not to mention the equipment. So, probably not economical.


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## Elektrikis (Jan 22, 2019)

https://www.youtube.com/watch?v=udTfxnh90Os

96% Sulfuric acid and nitric acid very good silver stripping.


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## ION 47 (Jan 23, 2019)

Elektrikis said:


> https://www.youtube.com/watch?v=udTfxnh90Os
> 
> 96% Sulfuric acid and nitric acid very good silver stripping.



The method works. There are several difficulties: 1. You can ruin the pants, 2. Protect your respiratory system, 3. Careful, hands, face, 4. The filter only through a Mineral filter, 5. It is necessary to restore the silver sulfate to the metal, it is an additional hemorrhoids.


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## rickzeien (Feb 4, 2019)

archeonist said:


> The only way I can think of is mechanically removing the silver plate. The experiment that I am going to do is sand blasting silverplate items. You'll end up with a mixture of dust that contains sand and metal particles wich are easy to seperate. I think this method would be fairly quick and low in costs as you don't need a lot of nitric. Still haven't got time to work this out but soon I will.


I use to clean injection molds for plastic with dry ice. The nice part about dry ice is the blast media (rice sized particles of dry ice) simply sublimates leaving nothing but the particles as residual. In this case silver and a small amount of substrate. 

Not sure if it would work with silver and perhaps gold plated items. Might be worth a try. 

Sent from my LG-H872 using Tapatalk


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## goldenchild (Feb 6, 2019)

kad,

In the video you estimated that the silver was probably 99% fine. It was most likely at least three nines. You must take into account that any copper in the water will be burned off during the melt since it's not a slow burn. Similar to how you can create crystals from concentrated solutions (gold, silver, copper etc) with a slow controlled boil but if you do it to quickly you can suffer massive loses. Since the amount of copper is already miniscule there is almost none left after the melt. I used this method and consistently achieved 4 nines. The key is to get the water crystal clear before adding the lye and sugar. 

Also, if you ever use this method again simple stirring will get all of the material converted. The exothermic reaction will boil the lye and sugar throughout the material. Just make sure whatever you stir with is glass.

Here is me using this method what seems like ages ago 8) 

https://www.youtube.com/watch?v=xM-YsiFnJ1I&t=2s


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## Shark (Feb 6, 2019)

goldenchild said:


> kad,
> 
> In the video you estimated that the silver was probably 99% fine. It was most likely at least three nines. You must take into account that any copper in the water will be burned off during the melt since it's not a slow burn. Similar to how you can create crystals from concentrated solutions (gold, silver, copper etc) with a slow controlled boil but if you do it to quickly you can suffer massive loses. Since the amount of copper is already miniscule there is almost none left after the melt. I used this method and consistently achieved 4 nines. The key is to get the water crystal clear before adding the lye and sugar.
> 
> ...



Trying to view the video I get this message:



> Video unavailable
> This video contains content from WMG, who has blocked it in your country on copyright grounds.


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## goldenchild (Feb 6, 2019)

Shark said:


> Trying to view the video I get this message:
> 
> 
> 
> ...


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## Owltech (Feb 7, 2019)

Yeah the first video I've ever seen on silver chloride conversion using lye and sugar! 10x!


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## ION 47 (Feb 8, 2019)

Shark said:


> goldenchild said:
> 
> 
> > kad,
> ...



Try here: https://www.youtube.com/watch?v=e0HNDxWi2IM


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