Non-Chemical KNO3 cell

[Anonymous]

I melted gold bearing scrap, fingers, foils, and contact points into a slug.
I am processing it in a jar with KNO3, Small amount of NaCl, and power supplied by a old phone charger. 5 v at .35 amp.

Appears to be workng well, I can see silver cloride in the bottom, copper nitrate in solution and brownish powder settling to the bottom.

This is only a test run to work out the kinks of seperating the fine gold from the AgCl any suggestions would be appreciated.

I am trying to develope a process were acids are only needed as the finish stage.

 

[Anonymous]

I would like to cast the anode as a sponge, does anyone know how to
sponge up the cast billet?

 

[Noxx]

James, why do you add any NaCl ? It can make some of your gold to go in solution.

My advice would be to make the electrolysis in Nitric acid solution or Ammonium Chloride solution.

Both will get you powdered gold at the bottom and silver in solution for further recovery.

 

[lazersteve]

Jim,

Alloying the gold to 25% with silver then treating with nitric acid will leave a spongy gold moss behind. It won't be solid, but it will form a sponge like mass. I have occasionally seen karat gold jewelry form a tan colored porous structure when treated with dilute nitric acid over a long period of time.

Steve

[Edit]Changed wording for clarity[/edit]

 

[Anonymous]

James, why do you add any NaCl ? It can make some of your gold to go in solution.

My advice would be to make the electrolysis in Nitric acid solution or Ammonium Chloride solution.

Both will get you powdered gold at the bottom and silver in solution for further recovery.

Slug is mostly copper, some silver and some gold. I did not add salt until it was running for a while. I did this to get the silver out of solution so it would be in a form that would be insoluble also so it would not plate out at the cathode.

I figured any gold that went into solution would be replaced by copper from the anode and by the KOH formed at the cathode.

I am keeping copper mostly in the solution, silver in the bottom with gold.
My belief, hopefully not wrong, that the silver chloride will not be affected by the acids to dissolve the gold, letting me only use acid when I am to the refining stage.

Jim

 

[gLyze]

Jim,

Alloying the gold with 25% silver then treating with nitric acid will leave a spongy gold moss behind. It won't be solid, but it will form a sponge like mass. I have occasionally seen karat gold jewelry form a tan colored porus structure when treated with dilute nitirc acid over a long period of time.

Steve

What do you mean by alloying the gold with 25% silver?
Do you refer to the inquartation methode?
Doesnt that leave gold in form of powder on the bottom if input into Nitric acid?

kr

gLyze

 

[AKDan]

Think opposite of inquartation which is 75% silver and 25% gold. Steve is saying to swap the two amounts and having 25% silver and 75% gold, which will leave the gold semi intact rather than as a powder.

 

[lazersteve]

Sorry for the misunderstanding, I meant alloy to 25% (6 kt).

Reverse inquarting (25% silver 75% gold) will allow AR to be used directly, but requires pure gold to bring up the karat. The gold produce from this reaction will also be of questionable quality and need refining a second time after proper washing and incineration.

Steve