No silver chloride when adding salt to nitrate solution

[liquidauction]

Hello again!

So I've read Hokes book and am following the "cheap gold" process for refining.

Taking 20g cheap gold scrap and mixing with 40ml water/40ml nitric
about 12 hours later most of the time I have a good digested solution.

Add water and decant my green/blue liquid into a large bowl

Take my foils/dust/and sludge to another receptacle to go through a sulfuric bath.

For all intents and purposes I have 2 main byproducts at this point. According to what I've read the blue/green liquid should be mostly silver nitrate. The characteristics are below:

has a white and gray sediment at the bottom

I need to get rid of some of my solution because I have so much I don't have any more room. I wanted to separate the silver as silver chloride per Hokes book. I diluted some table salt into a sample and while it turned it green there weren't ANY chloride clouds that formed. I kept adding until I saw some reaction and it turned very bright green

Does anyone know what might have happened? How to fix?

Thank you!

 

[philddreamer]

You would be better off cementing with copper; but if you want Ag/Cl, add a drop of HCl to make sure you have silver in the solution. If it's positive add a few more drops of HCl, then try salt again.

I had a similar experience once. I had over 8 T 0z. of silver & when I added the salt I had no precipitation. I added a drop of HCl & had a positive reaction. After adding some HCl, I tried salt & all went well. Why I didn't have a precipitate when I first added salt, I don't know.
Since, I cement my silver with clean copper. Is faster & easier.

Take care!

Phil

 

[liquidauction]

You would be better off cementing with copper; but if you want Ag/Cl, add a drop of HCl to make sure you have silver in the solution. If it's positive add a few more drops of HCl, then try salt again.

I had a similar experience once. I had over 8 T 0z. of silver & when I added the salt I had no precipitation. I added a drop of HCl & had a positive reaction. After adding some HCl, I tried salt & all went well. Why I didn't have a precipitate when I first added salt, I don't know.
Since, I cement my silver with clean copper. Is faster & easier.

Take care!

Phil

Can I precipitate with copper after having added salt? I only did this to a sample but for the sake of having 15 different things going on a once it would help. Also, why does Hoke suggest the silver chloride method instead of just cementing with copper. I assumed it was for purity sake.

 

[philddreamer]

Decant your solution, so you separate the ag/cl. Then cement with copper.
Cemented silver, if rinsed properly, can be 99% pure. For .999, run the silver thru a silver cell. There's plenty of information available on the mater.

I really don't know why she recommends it; other members can explain this.

It won't hurt to try converting the ag/cl, thus gaining some expirience with the process.

What was the source of the silver?

Phil

 

[liquidauction]

Decant your solution, so you separate the ag/cl. Then cement with copper.
Cemented silver, if rinsed properly, can be 99% pure. For .999, run the silver thru a silver cell. There's plenty of information available on the mater.

I really don't know why she recommends it; other members can explain this.

It won't hurt to try converting the ag/cl, thus gaining some expirience with the process.

What was the source of the silver?

Phil

The source was rolled gold pocket watches.

I've always used copper to precipitate silver from silver nitrate but since I'm reading Hokes book I'm "going by the book" for consistancy sake. BUT... like you said it seems easier and more economical to use copper....I'll wait for someone to weigh in on that one.

Thank you so much for your advise!

 

[Lobby]

Silver chloride is a mess. It's hard to filter. Just generally a pain for the home refiner.

Cement with copper instead. Much simpler.

But make sure you dispose of the copper nitrate solution appropriately. That means: don't dispose of it until you treat it:

- cement the copper with iron bars

- decant the iron containing solution and add lime to neutralize (precipitate the iron hydroxide). Stir well.

- You'll end up with clear water that's safe to dispose of, and iron hydroxide that's generally benign.


Perhaps others will chime in...

 

[Geo]

copper nitrate is as useful in some processes as any other chemical.i have several gallons stored and marked to identify. of coarse you cant keep it all but good clean chemicals should be saved when you can. if its just copper nitrate, the nitric acid can be reclaimed by evaporating and condensing. this process can yield good quality nitric acid that can be concentrated. if this is an option for you, do not mix your copper nitrate with the stock pot or otherwise neutralize the solution.