The action of NaCN

[Geld Konig]

Hi,
If I have a NiAg alloy the solution of 0,2% of NaCN take the silver of alloy or not? Or it depend of the composition of the alloy?
I have several resistor from NCR computer assembled in 1961 till 1963. Can I use NaCN 0,2% to take silver or is better use HNO3 50 % ?

 

[goldsilverpro]

If I have a NiAg alloy the solution of 0,2% of NaCN take the silver of alloy or not? Or it depend of the composition of the alloy?

You can try it, but I doubt if the weak CN will touch the alloy at all, even if the nickel is fairly low. Plain CN doesn't work well on most Au or Ag alloys. There are some CN nickel strippers used in the plating industry, that would probably dissolve both, but they require very high CN concentrations (120-180 g/l) plus the addition of NaOH and a lot of a nitroaromatic compound such as m-NBSS.

 

[Lino1406]

behave same with cyanide

 

[leavemealone]

Is there a reason NaNo3 is not being used? Can you not find nitric in brazil?If you can, dissolve it all,and precipitate the Ag with table salt,and wash.
Johnny

 

[Lino1406]

from AgNO3 sulution can be made
with NaOH solution, as Ag2O
which gives Ag on melting

 

[leavemealone]

HUH?!?!?! With sodium Hydroxide?! I think you may have worded that incorrectly.

 

[Oz]

Lino is correct, be careful though, it is not for the timid.

Nice to see you again leavemealone.

 

[leavemealone]

Lino is correct, be careful though, it is not for the timid.

I apologize,I guess I need to reread it.

Nice to see you again leavemealone.

Thanks oz,its good to be back.I have a lot of pics to post,but I need to take some time to resize them.
Talk to you soon.
Johnny

 

[Oz]

No need to apologize, you were politely questioning the procedure. I do not believe it has been covered here before and it does have drawbacks.

First and foremost, it is something that needs to be done with great care as you are mixing a strong base with a strong acid. Secondly, I would be concerned as to what contaminates you may have in your silver nitrate that may also readily form oxides. For these reasons I would not recommend it except in limited circumstances by someone with the proper lab equipment and experience. It is better in most cases to make silver chloride and have as your primary contaminate concern being lead chloride, as the 2 chlorides are not difficult to separate. Once you have a clean silver chloride you can then make your silver oxide with NaOH.