Silver conversion methods

[Refinerjohn]

Hello all,
I’m curious to see what the thoughts and experiences with iron or aluminum to convert silver chloride. I’ve seen in a few videos now and have read a few times here and there that using iron/aluminum will leave you with an incomplete conversion, I’ve never used the method myself and I’m interested to hear any opinions on the matter or if anyone has had negative results.

 

[4metals]

As far as using iron, read this thread where using an Iron frying pan for the process is described.

I have never used aluminum and if at all possible I avoid forming the Silver Chloride entirely and use copper to cement the Silver out as a metal. If you have no choice when the Silver Chloride comes from an aqua regia refine, the iron method is effective for smaller lots and the larger lots were treated with caustic and corn syrup.

 

[Shark]

Lou once mentioned that the sulfuric and iron method was better used on large, potentially dirty lots of silver chloride over the lye/sugar method. Since then I have always used the iron and sulfuric method.

 

[Refinerjohn]

Lou once mentioned that the sulfuric and iron method was better used on large, potentially dirty lots of silver chloride over the lye/sugar method. Since then I have always used the iron and sulfuric method.

Makes sense. Thats what I was hoping to hear. I’ve got a bunch of very dirty silver chloride from an old nasty chore of a stock pot and I want to convert it as is so I can efficiently go after everything there.
I was concerned that I wouldn’t get totally conversation and there would be a fair amount of chloride left. After hearing that and reading a bit, I’ve got an 12” cast iron on hand luckily so I’m going to give it a go. Seems to be the best next step without completely cornering myself.

 

[Shark]

Makes sense. Thats what I was hoping to hear. I’ve got a bunch of very dirty silver chloride from an old nasty chore of a stock pot and I want to convert it as is so I can efficiently go after everything there.
I was concerned that I wouldn’t get totally conversation and there would be a fair amount of chloride left. After hearing that and reading a bit, I’ve got an 12” cast iron on hand luckily so I’m going to give it a go. Seems to be the best next step without completely cornering myself.

Just remember that every bit of the chloride must contact the iron enough to get complete conversion to silver. Through stirring is a must.

 

[4metals]

Whenever I ended up with dirty Silver Chloride muds I dissolved the Silver out in ammonia, filtered off any solids and then used Hydrochloric Acid to drop the clean Silver chloride specifically to clean the Silver to 99+ purity with less steps and sell it off. I then converted the well rinsed Silver Chloride to Silver oxide and melted it directly as the oxide. Skip the corn syrup. I never was a fan of the iron pieces method because fishing out the pieces of iron was never easy. The frying pan method erodes the pan to the point where it is so thin you cannot use it anymore. But there were never any missing iron pieces to affect the purity.

 

[Shark]

I have never used ammonia but it sounds like less work. Might need to give it try as I have sterling on hand just waiting for something to be done with it.

 

[4metals]

I have never used ammonia but it sounds like less work. Might need to give it try as I have sterling on hand just waiting for something to be done with it.

The use of ammonia was only to dissolve the Silver Chloride because it was dirty, it was not from a clean source like sterling it was from settling tanks and cementation of wastes. The waste I had needed filtration, and simply filtering it all would give me a dryer version of what had settled out of the cementation process. The ammonia allowed me to easily dissolve the Silver Chloride out of the mix so I could separate the Silver from the other cemented metals.

I do not like using ammonia with Silver and always acidify the solution when I am done. Using hydrochloric to drop the Silver as a chloride accomplished both the dropping of a clean chloride and acidification of the ammonia solution.

I would consider what I used the ammonia for a special case for nasty mixed metal cementation wastes.

 

[anarxi]

I ,always make silver through chloride.
nitric acid is always in excess, then adding hydrochloric acid produces high-quality aqua regia, which dissolves many undesirable metals..
restore it with aluminum + hydrochloric acid.
If I know that there is a lot of tin in the chloride, (after sulfur-nitrogen melange) I restore it further, then wash it with hot water, (by decantation) then sodium hydroxide, then again with hot water and dissolve it again with nitric acid...

 

[Shark]

The use of ammonia was only to dissolve the Silver Chloride because it was dirty, it was not from a clean source like sterling it was from settling tanks and cementation of wastes. The waste I had needed filtration, and simply filtering it all would give me a dryer version of what had settled out of the cementation process. The ammonia allowed me to easily dissolve the Silver Chloride out of the mix so I could separate the Silver from the other cemented metals.

I do not like using ammonia with Silver and always acidify the solution when I am done. Using hydrochloric to drop the Silver as a chloride accomplished both the dropping of a clean chloride and acidification of the ammonia solution.

I would consider what I used the ammonia for a special case for nasty mixed metal cementation wastes.

I have some silver chloride on hand that came from digesting uncleaned gold filled using sulfuric/sodium nitrate and water. It is waste from trying various work around methods for gold filled. I could experiment with a small bit of it. I find it interesting and something I haven’t tried yet.