It is possible to separate silver from tin by melting/smelting ?

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razvanflorin

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Hello !! i have a question.. It is possible to separate silver from tin (3.5% silver 96.5% tin) by melting or smelting ? if yes, please give me more details about the process :D
 
Leadless soldering flux - better to leave it for what it was designed for than losing money on separation (and then mixing it again since what will you do with all that tin?)
 
This is another application for the use of silver which economics make unviable, that reason also includes many plated items and it’s use in double and triple glazing glass, it always amazes me when silver has so many industrial uses for which there seems no other metal or material substitute that it’s price is so low making its recovery untenable.
 
razvanflorin said:
Hello !! i have a question.. It is possible to separate silver from tin (3.5% silver 96.5% tin) by melting or smelting ? if yes, please give me more details about the process :D

How much do you have?
 
When i melting old tin cups and candle light Sn for scrap bars the upper side contain mutch more Sn.
The bottom have a higher lead %, i guess it is because the higher gravity.
Perhaps if you melt it in a long pipe the silver % will be high enough in the bottom of the pipe to collect it for recovering?
 
Just keep searching for the word solder.

https://archive.org/stream/preciousmetalsre00unit/preciousmetalsre00unit_djvu.txt
 
Thanks for reminding me that I've got a good amount of it...I'll have to play with it now.

https://www.911metallurgist.com/blog/wp-content/uploads/2015/02/Recovering-Gold-From-Scrap-Electronic-Solders.pdf
 
The tin is worth more than the silver. Any refining method that doesn't recover both tin and silver incures a major loss.

Two tons per week is a decent amount to work with. I would research electrolysis of the tin, leaving silver as a byproduct in the anode mud. It can then be refined in a second step.

Göran
 
g_axelsson said:
The tin is worth more than the silver. Any refining method that doesn't recover both tin and silver incures a major loss.

Two tons per week is a decent amount to work with. I would research electrolysis of the tin, leaving silver as a byproduct in the anode mud. It can then be refined in a second step.

Göran
Not with silver in it it’s not.

Tin loses its value quickly once you add anything to it. Too hard to separate.

Electrolysis of tin is done in a salt bath at 450-559 deg c.


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snoman701 said:
g_axelsson said:
The tin is worth more than the silver. Any refining method that doesn't recover both tin and silver incures a major loss.

Two tons per week is a decent amount to work with. I would research electrolysis of the tin, leaving silver as a byproduct in the anode mud. It can then be refined in a second step.

Göran
Not with silver in it it’s not.

Tin loses its value quickly once you add anything to it. Too hard to separate.

Electrolysis of tin is done in a salt bath at 450-559 deg c.


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What I meant to say was that when separated in it's fractions and refined, the tin fraction holds the largest value.

You can also use electrolysis of tin with HCl bath in smaller scale. Here is an article about refining lead free solder.
http://www.qip-journal.eu/index.php/ams/article/download/161/120 (DOI 10.12776/ams.v19i3.161)
Alkaline baths can also be used but you need higher temperature to run it. (Around 80 °C)

An article about a tin refinery using electrolytic refining, producing 400 tons of tin per month.
Mackey, T. S. (1969). The Electrolytic Tin Refining Plant at Texas City, Texas. JOM, 21(6), 32–43. doi:10.1007/bf03378890
(Use the sci-hub site for access to the article)

Göran
 
Does anyone know of any hobbyist that is capable of refining roughly 60 kilos of electro-mechanical components with a silver contents within which have came from bombardier works in Doncaster which made the famous trains The Flying Scotsman and Mallard etc. Which was demolished a few years ago. Also, I have 50 kilos of various electrical contacts which came from various components from different sources from the 70’s and 80’s. I’m willing to give a reasonable percentage but these electrical contacts need to be further tested for gold/palladium etc. If we can both come to some satisfactory understanding regarding the silver and the electrical contacts I would be happy to go ahead with the process.
 
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These are the electrical contacts
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I could be wrong, but the first group of pictures look like silver plated copper I've worked with. It's easy to test them. Take a file and file a deep notch into a few of them and see if they're copper under the silver.

Dave
 
Excellent way to depopulate boards, I'm using a weak solution of hcl and well water, if your using the cell to clear the boards from chips let the boards soak in the electrolyte to get a good saturation of tin ions in the electrolyte before switching on the power supply.

As the tin ions are depleted from the electrolyte new ions are added from the solder on the boards when your electrolyte starts turning green this is an indication that the tin ions have neared depletion and your liquor is taking on chlorine.

Your boards can be stacked and do not have to make an electrical contact with the power supply, the boards are just used as a donor for the tin ion.

Those small surface mounted chips will be the first to come free.

Switch your power supply off for half an hour to allow more tin ions to enter the liquor, maybe remove boards that have completed to process then adding some fresh ones.

The chlorine will strip the gold from fingers etc. not sure if it is being precipitated into the cell slime's or going into the electrolyte.

Silver from the solder is left as cell slime's, a divided cell with a membrane would make harvesting easier. You may even get lucky and recover a bit of gold from the solder.

The large carbon rod is from a very old 1.5 volt dry cell from which I also harvested the manganese dioxide, stainless steel sheet if from a hard drive. And the power supply is from an old PC, I'm operating the cell at 12 volts DC.

For some off reason the silver component likes to gather around the positive electrode.

Work under a fume hood or outdoors.

wwavw.png
 
So far I've harvested about one pound of tin and recovered 4.4 grams of cell slime's. Time to build a larger cell.

cellslim.png

tinhravest.png
 
I have to agree with Jon on that.
A new test project on the horizon I think.
Thanks a lot for sharing.
 
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