# Some problems in my first experience ( Dissolve silver in nitric acid )



## saadat68 (May 27, 2017)

Hi
I had some problems in my first experience today.

1- I added slowly 1 liter nitric acid + 1 liter distilled water in some silver oxide batteries but after 2 minute acid fall out from erlenmeyer. 
http://uupload.ir/files/oefs_bjklljhg.jpg

2- I see large volume of sludge in my solution. It covers my solution. Is this sludge normal ? ( I added some used filter papers to my solutions. Do they produce sludge?) 

3- And major problem is NOx fumes. In videos in YouTube reactions complete in 20 or 30 minute. In my case I must add 2 liter acid to my batteries and I add 1 liter* but after 8 hours I still see NOx fumes * :shock: :shock: :shock: 
Why ? 
I add just 1 liter acid and some water and heat it. What is the problem ?


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## Topher_osAUrus (May 27, 2017)

Did you wash the batteries with water first?
They have a basic electrolyte.

Did you add the entire litre of nitric? Small additions are much MUCH better..


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## Palladium (May 27, 2017)

Use a stainless 5 gallon pot. From the looks of it you had some iron cases mixed in with the powder. Did you screen it first to remove the metal case fragments? When you have iron like that and you don't add enough nitric acid in increments to keep the solution on the acid side, less than ph 7, iron will start to come out of solution and cause this mess. Once you start keep adding acid and don't stop until you are finished with the reaction. 

Like Chris pointed out you also need at least two good washes to remove the zinc and the base which makes up the powder ( Potassium - Sodium hydroxide ).


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## Palladium (May 27, 2017)

Flasks and beakers are no good for this job if your going to do any volumes worth doing with batteries. Especially a flask since they form a restriction the further toward the top of the flask you get. It's like a volcano or a fire hose nozzle used to restrict liquid and boost pressure. You need room for the solution to expand. Your vessel needs at lest 3 times - 5 times the volume of your solution you plan to use. If you plan on using 1 gallon of solution, nitric and water, then you need a 3-5 gallon vessel.


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## saadat68 (May 27, 2017)

Palladium said:


> Flasks and beakers are no good for this job if your going to do any volumes worth doing with batteries. Especially a flask since they form a restriction the further toward the top of the flask you get. It's like a volcano or a fire hose nozzle used to restrict liquid and boost pressure. You need room for the solution to expand. Your vessel needs at lest 3 times - 5 times the volume of your solution you plan to use. If you plan on using 1 gallon of solution, nitric and water, then you need a 3-5 gallon vessel.


Thanks Topher_osAUrus and palladium 
I washed them but not good! because it was my first experience 

1- I don't remove the metal case fragments because I think silver oxides stick to them and I must separate them after acid leaching. Is it right ? How remove them? after milling with water?


2- If I use a pot for example 5 gallon pot, does it solve problem number 3

Thanks


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## Palladium (May 27, 2017)

I will get you some numbers from my notes when i get to my files in a little while at the shop. 
When you have washed them right to remove the base and when they are screened to remove metal fragments it takes very little nitric to dissolve a lot of powder believe it or not. If you don't do these steps it will take a wholeeee lot more nitric than needed. It's a very efficient process when done right. 

After you wash the batteries in a 5 gallon container with hot water pour the wash water with the powder through a screen to catch any metal fragments. This will eliminate the dusty screening part to remove the fragments. You can use something a simple as fiberglass window screen stretched over a 5 gallon bucket to catch them. Once you have it screened and the silver powder and water is in a bucket let it settle for about 12-24 hours. Draw the excess water off the powder leaving very little water. You can use a hose to siphon it off. Rinse the 5 gallon bucket into your stainless 5 gallon pot and this is your starting solution with water already added.


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## Palladium (May 27, 2017)

saadat68 said:


> 2- If I use a pot for example 5 gallon pot, does it solve problem number 3
> 
> Thanks



No it will not solve the nox problem, But........ Removing the base and the metal fragments as well as the base ( Potassium ) will cut done on the amount of nitric used and by doing this you will cut down the nox by a factor of 2x -3x times.


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## saadat68 (May 27, 2017)

Palladium said:


> saadat68 said:
> 
> 
> > 2- If I use a pot for example 5 gallon pot, does it solve problem number 3
> ...


Ok got it
Thanks 
And last question
After washing and screening how much acid do I need?
I know I must add 1 liter for 250 gram batteries but how much acid need for this way ? Because after screening they are just wet powder ( with excess of weight for water) and without cases


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## Palladium (May 27, 2017)

Are you going to be cementing this from solution with copper or are you going to be precipitating it from solution by using salt to make silver chloride?

Are you doing this in batches and then paying the customer on yield from that particular batch or are you buying the batteries for yourself and then processing them for yourself?


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## saadat68 (May 27, 2017)

I want to cement with copper because I had read cementation is better
I want to refine them and produce silver ingot and then sell


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## Palladium (May 27, 2017)

When done right it will take about 1.5 ml per gram of materials.
672 ml per lb of dry, washed, and screened materials.

Since you are going to cement with copper you don't want excess nitric in solution. The best way to accomplish this is to not digest all the materials. Batteries is not one of those things where you can really say X amount of nitric per X amount of materials. You can get close, but it's still just a guess. For this the best thing is your experience and your eyes! 

Add all of your materials except about a 1/2 lb to your pot with water. Add heat while adding acid in small amounts of around 500 ml and watching for the red gas. Wait about 15 minutes between additions while seeing how much red gas is coming off. Powders are fine and will go into solution real quick! When you add 500 ml and notice that the solution doesn't increase in bubbling or the red gas is not as thick as before stop adding nitric and add the 1/2 lb of materials you didn't add in the beginning. By adding this last amount of materials you will consume the last bit of remaining nitric making it a whole lot easier if you are cementing with copper. Heat for another hour on high and then turn off to cool. When you go to filter the solution you will notice materials left in the pot that didn't dissolve. Leave the materials in the pot while washing any solution out with water. The next batch you do will be added to the pot and the process starts over.


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## saadat68 (May 28, 2017)

Thanks
So I need just 310 ml acid instead of 2.5 liter for 600 gram batteries that refined yesterday WOW :shock: 
Today I thinked about other ways like participate silver chloride with sodium chloride 
Maybe this way is better choice for batteries, We don't need distilled water in this way as we must wash batteries very much 
But I read in an article recovery of silver in sodium chloride isn't high 
What do you think ? Cement with copper is best for batteries ?


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## kernels (May 28, 2017)

Cement with copper is the simplest way to recover silver metal from solution. But if you have a lot of excess Nitric acid, it will consume a lot of copper.

I haven't read the whole thread, so don't know if someone has already explicitly said this . . . start with smaller experiments until you know what you are doing and what to expect, pouring a liter of Nitric acid into a flask onto some material is . . . :shock: work with 50g of material until you have your process figured out.


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## Palladium (May 28, 2017)

saadat68 said:


> Thanks
> So I need just 310 ml acid instead of 2.5 liter for 600 gram batteries that refined yesterday WOW :shock:
> Today I thinked about other ways like participate silver chloride with sodium chloride
> Maybe this way is better choice for batteries, We don't need distilled water in this way as we must wash batteries very much
> ...



Are you talking about whole batteries or just the powder from the batteries?
If you had 600 grams of powder it would require 900 ml of 67-69 % nitric acid.
600 grams X 1.5 ml = 900 ml

Silver chloride on a small scale is easy, but on a larger scale is rather difficult if your not set up for it in your lab. It requires a conversion process that will add a lot of waste to your stream.
I would stick with copper cementing and set up a simple silver sell because it is more forgiving if your not experienced with the chloride conversion or don't have the right equipment. Unless your water is ridiculously high in chlorine you can use city tap water. The small amount of chlorides produced is very little silver loss and won't interfere with either process. Now for a silver cell you want distilled water!


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## saadat68 (May 29, 2017)

I had 600 gram batteries and used 2400 ml 57% nitric acid
If I washed and screened them I had max 210 gram (0.46 lb ) dry powder that need just 309 ml acid  

Can I wash them with tap water or use tap water for leaching and cementation and then remove chlorine with silver cell and then melt silvers 
Or Do I must use distilled water in all of process 

I must search in forum about this but now I must go to workshop


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## saadat68 (May 29, 2017)

I don't want loss silver or make problems in melting. My problem is just washing batteries. 
What happen if I wash them with tap water and let to dry and then leach with acid and distilled water ( then go for cement and melting ) ?
In this way do I lost any silver or produce silver chloride ? If yes how much?


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## Palladium (May 29, 2017)

Are you trying to produce silver to sell to consumers ( general public ) or are you trying to produce a clean product to sell to a refinery?


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## saadat68 (May 30, 2017)

Hi
Sell to consumers


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## saadat68 (May 31, 2017)

Hi
Can I use coffee filter instead of filter paper for filtering Silver Nitrate solution? 
I have sheet filter paper and I don't know what is it's size and brand. After 3 days I filter just half of 3 liter solution!!!


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## Topher_osAUrus (May 31, 2017)

Sounds like you should have let it settle and siphoned off the clear solution, only filtering the last bit.
Sometimes thats just the best way to go about it.


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## saadat68 (Jun 1, 2017)

Topher_osAUrus said:


> Sounds like you should have let it settle and siphoned off the clear solution, only filtering the last bit.
> Sometimes thats just the best way to go about it.


In first experience I don't wash good and don't screen and also I add filter papers and napkins!!!
So I have much residue. I don't Know what are in residue really but I hope They are not silver oxide :? 

As palladium said I must don't digest all of my powder so in this way I have considerable residue too. Yesterday I searched in forum and found that decanting is best way but after decanting I must filter to catch any silver powders 
A coffee filter can catch all of powders ? like whatman size 4 
Buying a coffee filter is easier and cheaper


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## saadat68 (Jun 28, 2017)

After filtering silver nitrate solution several times with filter paper sheet and coffee filter I see some residue in solution!!! 
What's wrong ? I am really confuse and don't want loss my silver.
What are these residue that excess nitric acid can't dissolve them?

My silver nitrate solution is brown and residue is bright brown
http://uupload.ir/files/ijko_vjjmmbkkh.jpg


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## Lino1406 (Jun 28, 2017)

Tap water in the mid east can have 250mg of chloride salts per liter. What converts to silver chloride. To check, just collect some precipitate and add concentrated caustic. If you get nice black, it is silver.


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## saadat68 (Jun 29, 2017)

Thanks Lino 
I add caustic and they convert to black powder immediately. In some steps I used water from well ( My workshop is in the park ) and I thought because it doesn't have Chlorine it is OK I forget it may contain salt. It was my mistake. 



Palladium said:


> After you wash the batteries in a 5 gallon container with hot water pour the wash water with the powder through a screen to catch any metal fragments.



Hi Palladium 
Do I must wash batteries with distilled water? Can I use tap water in this step? It is very cheaper 
Thanks


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## Palladium (Jun 29, 2017)

Tap water is fine.


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## saadat68 (Sep 23, 2017)

I did what Palladium said but after one day some of gray cements turn to brown :shock: 
Is it normal?
I had excess nitric acid but I don't think I did another mistake 

http://uupload.ir/files/028k_img_20170923_182554.jpg

http://uupload.ir/files/ajxg_img_20170923_212956.jpg


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## g_axelsson (Sep 23, 2017)

That doesn't look like silver cement to me. How did you cement it? On copper?

I think a lot of your problems comes from the fact that you have zero experience working with silver. Starting with button cell batteries only adds a lot of unknown variables into the mix.

To be frank, you have worked on this project for at least four months now and anyone the least experienced in silver chemistry would know that taking some of your "silver cement", add it in a test tube and a few ml of nitric acid would dissolve it if it was indeed silver cement. Add some HCl or table salt and it would form silver chloride. That test would take less time than it takes for me to write this post.

I suggest that you buy some sterling silver scrap or some scrap silver coins and learn the different reactions of silver. Do the tests that Hoke recommends for silver. You should also test three different methods to recover your silver. Sugar + lye, sulfuric + iron and cementing. This is something you can do in less than a day and it will show you how silver reacts.

Here are the Hoke acquaintance experiments.
http://goldrefiningwiki.com/mediawiki/index.php/Hoke_acquaintance_experiments

Göran


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## saadat68 (Sep 23, 2017)

@g_axelsson

Thanks but I just dissolve powders after washing and added a copper bar to it in first hour cement was gray but after one day it turns to brown (not all of them)  
Why add nitric acid to it when I had a transparent solution before cementing ?
And now I have silver cement without solution. Why add hcl to it? (I don't have silver nitrate)

I really don't have time to learning more. I must melt my silver this week and start my business and earn some money!


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## jimdoc (Sep 23, 2017)

saadat68 said:


> @g_axelsson
> 
> Thanks but I just dissolve powders after washing and added a copper bar to it in first hour cement was gray but after one day it turns to brown (not all of them)
> I really don't have time to learning more. I must melt my silver this week and start my business and earn some money!



If you don't have time to learn, you don't have time for business.
At least a successful business.


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## saadat68 (Sep 23, 2017)

jimdoc said:


> saadat68 said:
> 
> 
> > @g_axelsson
> ...


Yes but in future 
Now I must earn money because I rent my workshop and remains 5 month of my contract


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## saadat68 (Sep 23, 2017)

Palladium said:


> Tap water is fine.


Hi Palladium
I need your help again!
http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=50&t=25632#p277475


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## saadat68 (Sep 23, 2017)

3 months ago I tried to digest some powders with sulfuric acid and H2O2 but after I got silvers again with cementation and add cements to my batteries powders 
Is that problem ?

Can I wash it with hcl after drying ?


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## Palladium (Sep 23, 2017)

All i can think of is you diluted your solution during cementation and iron precipitated out. Theirs really nothing else in there that could cause brown! Zinc is below copper and will stay in the solution and the hydroxides, if any were left from your water wash would have been killed off by the acid.


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## saadat68 (Sep 24, 2017)

Thank you
Fortunately brown sludge gone easily with HCl 
This is my silver cement.  

http://uupload.ir/files/c95g_img_20170924_213231.jpg
--------------
I think I added a little water and also added some silver nitrate solution again 
But why? 
Water raise PH of solution and precipitate iron hydroxide. Right ?


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## Topher_osAUrus (Sep 24, 2017)

Pretty dark for cemented silver.
Maybe some silver chloride has contaminated it and darkened by sunlight.

Id melt with a little bit of soda ash. Just in case


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## saadat68 (Sep 25, 2017)

Topher_osAUrus said:


> Pretty dark for cemented silver.
> Maybe some silver chloride has contaminated it and darkened by sunlight.
> 
> Id melt with a little bit of soda ash. Just in case


It was wet and fresh and in my workshop
I thought it is black because it is wet. Today I wash again with a little HCl and tap water. It is a little brighter but not same cements in youtube videos. 
Maybe it is better to dissolve again in nitric acid 

2 image from wet cement after washing today:
In sunlight:
http://uupload.ir/files/dico_img_20170925_144632.jpg

In workshop:
http://uupload.ir/files/6li7_img_20170925_144729_1.jpg


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## Topher_osAUrus (Sep 25, 2017)

Why HCl? Finely divivded silver cement plus HCl = AgCl.
It should only be in small quantities, unless you heated it or had oxidizer in it. But still, just seems counter intuitive to progress


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## saadat68 (Sep 25, 2017)

Because I had iron in my solution
http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=50&t=25632#p277475


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## Topher_osAUrus (Sep 25, 2017)

Iron and silver are immiscible. 
You could have rinsed very well in hot water and tried to effect separation. Then just dried it and melted whatever didnt get washed away. Iron does not alloy with silver.
Or, you could have used dilute sulfuric, which would have dissolved the iron and left the silver alone.


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## saadat68 (Sep 25, 2017)

OK
Thanks Topher
I ruined my second experience too 
It is embarrassing

Today I tried to dissolve them with nitric acid. Most of them didn't dissolve. Residue is purple now and sounds like I make silver chloride. :? 
But why purple ? Yes I know UV *changes *color to purple and I have fluorescent lamps in my lab but I didn't see any white powder. They were black after adding HCl and they were purple after digest in nitric acid
Tomorrow I will try to convert silver chlorides to silver with sugar


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## Palladium (Sep 25, 2017)

You said you had excess nitric in you solution when you went to cement it. The dark color is probably from copper contamination. This was before you tried to wash it with hcl of course! You're getting some good experience as what to do and what to not do though. Hcl will remove the iron, but not the copper. Hcl requires an oxidizer or elevated heat to attack the copper. Like Tropher said, iron and silver don't mix, you should have just melted it and run it in a cell. Sugar alone won't work for conversion. Use a hydroxide and convert it to silver oxide, don't add sugar, wash well with water, then nitric will dissolve it again. One way you could have cleaned it up was to add a small amount of nitric and water to the powder and heat it up. This would dissolve any copper or iron leaving the cemented powder fairly clean. You then take that wash water and put it back into a bucket with the next batch that needs cementing and any silver that was dissolved in the washing step would be recovered in the next batch.


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## saadat68 (Sep 25, 2017)

Thank you Palladium
I will review some topics in forum before start silver chloride convert 
I don't have time for more mistake really

So problem was copper :? 
Tonight I dissolved some powders again. They were a little residue from previous step
I couldn't find the weight of powders because they were wet but I tried add less acid that you school me
You said boil it 2 hour in high temperature and tonight I boiled it 3 hours!!! and still I have excess nitric 
Also I have some undissolved powders that sound like nitric is less than powders. 

Is it normal ? You don't have any fumes after 2 hour? 
I don't want deal with excess nitric and copper again and lost my silver in third experience 

I hope I added much acid that cause take 3 hours


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## saadat68 (Sep 26, 2017)

Last day I had excess nitric acid in my solution and today I add silver oxides to solution for consuming excess nitric and heat it for one hour again. I didn't see any red fume.

*Does settling help to consume nitric acid? *
Why there was nitric in my solution but after settling for one day not?


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## saadat68 (Sep 27, 2017)

I have excess nitric again 
Why? I heated it for 4 hour
I had undissolve battries powder too


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## Topher_osAUrus (Sep 27, 2017)

saadat68 said:


> I have excess nitric again
> Why? I heated it for 4 hour
> I had undissolve battries powder too



You are assuming the solids are soluble in nitric. They must not be (assuming you had plenty of agitation so the material was in contact with fresh acid)

If this is the stuff that had some of it turn to chloride, there is your problem.
You can try and try and try but it will not go into solution. It needs converted first. Either to metal or oxide.


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## saadat68 (Sep 27, 2017)

Thanks 
I converted them with naoh to oxide 
Also I had some battries powders too 
In previous experience I had same problem. Many times I saw water vapors but any red fumes 
I think I must rotate solution more. Maybe powders don't contact to acid


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## upcyclist (Sep 28, 2017)

saadat68 said:


> jimdoc said:
> 
> 
> > saadat68 said:
> ...


I'm go back to this one--you'll have better luck if you perform those familiarization experiments *now*. Right now, you're working blind, then posting the results here and waiting for more help. Also, you're having problems describing what happens because you haven't taken the time to learn. 

You will not magically figure out everything tomorrow and earn some money, then get to that magical "future" when you have time to learn. Learn now. Before you waste more of your time, and spend more time without income.

To put it another way (darn Upcyclist and his analogies), you're saying, "I don't have time to buy and feed chickens! I must have eggs to sell!"


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## saadat68 (Sep 28, 2017)

Thank you
I am in learning for one year
*I accept I need more learn but I have own conditions. 
*Before I post here I search in forum and read some or read my notes and my topics several times or see videos in my computer
I am working in my workshop for 5 to 8 hour for just learning


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## saadat68 (Oct 2, 2017)

Hi, I have a question
Can I use this process for silver oxide batteries ? 
- Crush and wash 
- Mercury distillation 
*- Leach powders with dilute HCl to remove zinc and impurities 
- Melt with some soda ash
- Run to silver cell and melt again*


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## Topher_osAUrus (Oct 2, 2017)

saadat68 said:


> I am working in my workshop for 5 to 8 hour for just learning



You make it sound like learning is a chore. Maybe it's just me, but I love learning new things, and I would do it 18 hours a day if I could. Trying to do that extensive amount of edification has made it so I can refine decently, and if issues arise, I can alleviate them under my own accord.

As far as your recent question. Sure you can try to melt it, but I have a feeling you will be coming back shortly there after asking how to recover silver from solid slag.
Trying to melt impure metal can be a headache. Its best to recover and refine while in a powder form. It goes much faster. Try to master the standard practice before undertaking altered processes.


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## Shark (Oct 2, 2017)

Topher_osAUrus said:


> Try to master the standard practice before undertaking altered processes.



saadat68
I have been following this thread from the start along with the other related threads and I can not figure out why you avoid the tried and proven methods. You say you need to accomplish things quickly and yet you keep looking for new ways to do things before understanding your previous attempts. When I follow a process and something goes wrong I do not try another method. I will try it again and try to identify where my mistake was made. This way I can avoid it next time, and reduce the time it takes me to produce good results. By trying another method I often find that I create new problems that I don't understand and find that I am again wasting time. 

All that wasted time testing new methods are fine so long as you have time. If you need to produce material to sell, don't experiment, follow the proven methods. The the time you save can be used to study other methods, giving you a better understanding of them when you get around to trying them.


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## saadat68 (Oct 3, 2017)

Thank you Shark and Topher
You right I am sorry 
-------------
I tried to convert silver chlorid again now they are completely black and I will digest in nitric tomorrow 
My cement was green. It had copper contamination. I wash them many but it doesn't clear so I wash with dilute nitric. The residue is clear now but not like a water. It is very very little green. My cement is gray  
I wanted to melt cemented silver and sell 99% silver
But now I think it is better to make a silver cell and solve my problems this way (Excess nitric >> copper contamination >> need washing many )


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## Shark (Oct 3, 2017)

If you wash silver cement with nitric acid will that not dissolve some of your silver also?


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## Topher_osAUrus (Oct 3, 2017)

Couple things.

It is incredibly difficult to rinse silver cement. What I do, is stir it really well, and sit the vessel at an angle so the cement will pack up on one side of the beaker or bucket. Then I siphon off as much liquid as humanly possible. Before starting another rinse, I stir the cement up, or tap the vessel on the bottom multiple times (or both) to liberate more liquid trapped in the cement chunks. After that, I add more boiling hot water to it. Repeat and repeat until the rinse water passes the ammonia test (take a small sample of rinse water, add a small amount of ammonia, if it turns blue, it has copper ions in the rinse still)

Doing it this way has cut my washing cycles down exponentially. It should help you a great deal.

Secondly, a silver cell is a must. I know I wouldnt feel comfotable selling silver to clients when its purity is questionable (at best). You may have a 99% batch (if you are patient with the rinses, and lucky), but 97 to 98% is more par for the course. With a silver cell though, your product will consistently be 99%+, unless you let the electrolyte contamination climb too high, and run too high of a voltage. Also, it is much better (easier, cheaper, faster) to just sell silver crystals. Saves you time for melting, gas for melting, and the hassle of someone wanting 500g when you only have a kg bar. With crystals, you can sell $21 and 23 cents if you need to. Its a win win win win win. 

Did I mention the anode slimes keep the PM values in your pocket and not the buyer? Because there is that, too.


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## saadat68 (Oct 5, 2017)

Shark
I saved residue for next batch 

Topher
Thanks 
I will use your advice for next washing. Selling crystals is harder than silver shots here but I will test


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## saadat68 (Oct 9, 2017)

Hi
Now I know why most of users in this forum hate silver chloride
I tried 4 times to convert silver chloride to silver oxide with NaOH but I couldn't
I don't know what is problem. I add NaOH and stir them for 20 min with hand then wash and filter and add nitric acid
When I added nitric I didn't saw any red fumes. I saw just white fumes. What is these fumes ?
It is not important to recovery these silvers because I lost 90 percent of my silvers but I want to know what is the problem. Why I didn't see any red fume in 4 times.
I could recovery 40 gram cemented silver from 400 gram silver!!!!!! I lost 360 gram in 3 experience 

http://uupload.ir/files/gi1i_img_20171009_195308.jpg


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## upcyclist (Oct 12, 2017)

saadat68 said:


> Now I know why most of users in this forum hate silver chloride


I hear that, haha



saadat68 said:


> I tried 4 times to convert silver chloride to silver oxide with NaOH but I couldn't
> I don't know what is problem. I add NaOH and stir them for 20 min with hand then wash and filter and add nitric acid


A little more detail please. From your picture, it appears that at least some of the white silver chloride converted to black silver oxide. Did you rinse the AgCl to clean it up and raise the pH before adding the NaOH? After you added the hydroxide and got at least partial conversion, did you rinse that substance to remove the chlorides? If not, they're still in the mud, and as soon as you added the nitric acid, they converted your dissolving silver immediately to silver chloride again.

My formulas may be a bit off, but to at least show the fact that you need to get rid of the chlorides:

2AgCl + 2NaOH --> Ag2O + 2NaCl + H2O

If you get rid of the chlorides (salt), Ag2O + 2HNO3 -> 2AgNO3 + H2O

If you don't, you get Ag2O + 2HNO3 + 2NaCl --> 2AgNO3 + 2NaCl + H2O --> 2AgCl + 2NaNO3 + H2O


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## Topher_osAUrus (Oct 12, 2017)

In your case saadat, I wouldnt have messed with lye and sugar. I would have went with dilute sulfuric and nails... It will eat up any iron powder mixed in the chloride and the nails convert the silver chloride to silver metal.


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## saadat68 (Oct 13, 2017)

Hi
I think I rinsed well but you right problem is rinse. I did mistake somewhere. I hate rinse and filtration 
I added them to trash 2 days ago!!!
But I still have a little from filter paper and residue. I will try to convert them with iron method just for learning 

Thanks


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## saadat68 (Oct 14, 2017)

I read this post in another topic from Lou


> You speak of silver nitrate--it reduces itself to a black film of silver metal on your eyes, giving you ''black eye''. This is what happens when you get dust of luna salts in your eyes, or even when you melt it.



I can't clean cemented silver. I washed them many with boiling water but still there is a little contamination. Residue is a little green that seems it is copper nitrate.
I decide make a silver cell and get pure silver this way and always melt cemented silvers with a little contamination 

Is it dangerous ? :shock: I will wash them but If cemented silver has some copper nitrate and silver nitrate can it hurt me ?


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## saadat68 (Oct 21, 2017)

Palladium said:


> Tap water is fine.


Hi Palladium. I think just you can help me
In fifth experience I had a good leaching and cementation. I thought I learn leching step but I produce some silver chloride again!!!!
http://uupload.ir/files/serg_img_20171021_173340.jpg

I just used tap water in washing step. My process:
Wash 100 powder with tap water
decant 
Drying (100 gr powder with maybe 0.5 liter tap water )
Go for leaching after 2 days 
These residue don't dissolve in nitric. I test them twice 
http://uupload.ir/files/scpr_img_20171021_204205.jpg
I am really confuse. How these silver chlorides produce? From what?
-----------------------
I really want to go out from this business but I can't also I don't think can find sterling silver for refining


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## Topher_osAUrus (Oct 21, 2017)

Tap water has chlorides in it
Any chlorides plus AgNO3 = AgCl

Whether its during your dissolve, during your wash, or whatever -the chlorides from the tap water will make insoluble chloride.
-That is your delimma.

And, anyone can find sterling or gold. Its everywhere. You just need to find the right person or people to buy from or refine for. But, before working on other peoples material. I highly suggest first becoming proficient in the standard processes.


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## saadat68 (Oct 21, 2017)

Thanks Topher 
I still have a little powder. I will use distill water in washing step :? 

*But when I added powders to nitric they are completely dry!
*
Maybe they are MnO2 :shock: 
Edit: I think all of these days I deal with MnO2 not silver chloride
I don't like refine gold because I must start learning from first 
I will investigate some about silver sterling but I am not optimist


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## Topher_osAUrus (Oct 21, 2017)

saadat68 said:


> Thanks Topher
> I still have a little powder. I will use distill water in washing step :?
> 
> *But when I added powders to nitric they are completely dry!
> ...



I need some clarity.
You dissolved the powders initially, then cemented, then washed with tap water. Made some silver chloride, that you then dried and tried dissolving again?
May I ask why?

There is a couple things you could have done and actually got the silver done and melted by now instead of starting all the way back at step 1.

Palladium has been busy lately, and I dont know if he will even see this. So I can try to help you.
-1; you could have just melted the silver with the little bit of chloride in the mix, just using soda ash flux in addition to borax (not the best idea, as the fumes are absolutely terrible, and there will be losses)
-2, dissolve the silver chloride from the silver cement with ammonia hydroxide (immediately acidify the diammine silver chloride complex, never let it sit and dry, it can and will go boom)
-3; a quick wash with sodium hydroxide would have converted the chloride to oxide, which could have been washed, dried, and melted with there being no consequence to the metallic silver cement. (Thats probably the best option Id say)

Tap water can be used to wash your silver cement, but (this is a big but here), your silver must all be cemented out of the nitrate solution. Otherwise, well, its obvious now I'm sure, but -silver chloride- happens.

Since you have dissolved it all again, just filter off the silver chloride. Then cement out the silver and after its all out of solution, start rinsing and washing and cleaning it up. That chloride on the filter is going to be harder to convert now since it has dried. It's undergone a change in the crystal structure and what not, so I would just put it back for later down the road after you have gotten accustomed to the standard reactions.

Personally, I think gold is much easier to refine than silver. Its much more forgiving, at least. So long as you follow common practice, i mean.

Edit to finish -oops-


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## saadat68 (Oct 22, 2017)

Thanks for your helping
No, After crushing I wash batteries with tap water to remove electrolyte (Potassium hydroxide) and some zinc 
Decant and let them to dry and then add nitric >>> filter 
Residue is from this step. They don't dissolve in nitric 

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=50&t=25632#p272761

I still have a little batteries. I will wash them with distilled water and then add nitric if I have residue that don't dissolve in nitric so they are MnO2


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## saadat68 (Oct 22, 2017)

sound like they are MnO2 not silver chloride 
I dissolved a little powder today without washing. Just used distill water. I had residue again. They are black 
I must have 130 to 150 gram cemented silver. After cementation I will weigh cements and if they are 130 gram or more so I didn't loss silver as AgCl 
http://uupload.ir/files/8hmj_img_20171022_193809.jpg


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## Topher_osAUrus (Oct 22, 2017)

Silver chloride turns black in sunlight, but can revert back to white if covered from sunlight for long enough.

Carefully dry your cement until it is just moist powder, then turn up the heat. Bring it to a dull red heat with a torch, but do not melt it (this should be done in a corningware pyroceram dish or stainless pan)
You will see some red NO2 gas coming off (its impossible to rinse 100% of it out) and the silver will lose some volume (shrink a bit). After it cools, then weigh it. It will be a pretty close weight to what you will have after melt (assuming there is no silver chloride and you dont have substantial melt losses)

Again, if you are worried those MnO2 powders having some silver chloride mixed in, there are a couple methods you can use to dissolve the AgCl away from the MnO2. I mentioned one earlier, maybe both, I dont remember, as this thread is epic in length.
Ammonia hydroxide or sodium thiosulfate can each do it.
-personally, I would just keep that black ball of whatever it is moist and worry about it later, focusing on recovering the silver cement.


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## g_axelsson (Oct 22, 2017)

Is there any MnO2 in silver oxide batteries? Nothing I can find would support that.
Then the starting material wasn't sorted well.

I don't have time right now to try to refine my silver oxide batteries. It has to wait until later, so if I'm wrong just let me know.

Göran


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## saadat68 (Oct 22, 2017)

Thanks. Got it
Residues were black from first and don't turn to black also I don't have sunlight in my workshop.
I am not worry about mixing silver chloride in residue. If they are silver chloride I prefer to add them to trash!!! 
I just worry about next process. I want leach my batteries without any problem especially without producing AgCl in sixth experience.

g_axelsson
Is there any MnO2 in silver oxide batteries? No 
http://uupload.ir/files/ilze_untitled_-_2.jpg

I sorted them but yes they had a little alkaline cells 
My residue are high so I am suspicious.


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## g_axelsson (Oct 22, 2017)

I still think you should do some tests with known silver to learn the chemistry or you will never recognize what is happening.

Göran


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## saadat68 (Oct 22, 2017)

If I could get silver sterling here I switch to sterling! 
If this residue be just MnO2 and my cements be minimum 130 gram I think I learn leaching step


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## autumnwillow (Oct 29, 2017)

saadat68 said:


> Hi, I have a question
> Can I use this process for silver oxide batteries ?
> - Crush and wash
> - Mercury distillation
> ...



Method 1:
1 - Crush and wash
2 - Mercury distillation
3 - Digest in nitric (Silver and other base metals will dissolve)
4 - Filter
5 - Add hcl in filtrate (Sliver will precipitate as silver chloride)
6 - Filter
7 - Wash residue until pH is equal to wash water (Pour all in a filter paper to save wash overs)
8 - Put filter paper from step 7 and residue from step 7 in a bucket, add 10% sulfuric and iron nails, mix with pvc pipe until it looks like sand.
9 - Wash until pH is equal to wash water (Pour all in a filter paper to save wash overs)
10 - Dry and melt.

Result from this method should yield 99% silver. Who are your buyers? What is their requirement? If they need 99.99% put in a silver cell.

Method 2:
1 - Crush and wash
2 - Mercury distillation
3 - Digest in nitric (Silver and other base metals will dissolve)
4 - Filter
5 - Cement with copper
6 - Filter
7 - Wash residue until pH is equal to wash water (Pour all in a filter paper to save wash overs)
8 - Dry and melt.

Result from this method should be about 95-99% depending on the form of copper you used. Wires will contaminate it more, a large bus bar is better. Proceed with silver cell if higher purity is required.

There is another method which is shorter but since you have mercury in your lot I suggest not doing it as small contamination of such could be deadly.

Although method 1 takes more time, it is actually cheaper and you don't have to worry about silver chlorides because you are making them anyway. Iron is relatively cheaper compared to copper. Sulfuric acid used here is reusable. Your waste from hcl/nitric can be re-used or treated for disposal.


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## saadat68 (Oct 29, 2017)

> There is another method which is shorter but since you have mercury in your lot I suggest not doing it as small contamination of such could be deadly.


Thanks 
Can you explain other method ? 

-----------
My cements are little. I don't know I lost silvers or silver oxide batteries were fewer than I calculated 
My batteries were 350 gram 
Maybe I had 50 gram MnO2 battries that I could not separate 
300 gram X 30% = 90 gram 
Maybe I have 10 gram silver in filter papers and crusher
So I must have 80 gram silver cement in worst condition 
I get 45 gram!!!! 

I must say I lost. I accept it
--------------
Edit: 
I buy some batteries and want to try again
This is my last try!


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## saadat68 (Nov 26, 2017)

Because you advice me to refine gold or silver sterling I researched some about them 
Gold: Price is on the spot or sometimes high! Also selling gold shots/ingots is very hard and I must get assay and have license...
Silver: Price is 85% of spot but I can not find enough sterling. Competition is very high and sellers prefer sell them to jewelry makers.
So only choice is button cells and maybe electronic scraps. Both of them have toxic metals 
----------------------------------------------
Today I refined one kilo silver oxide batteries. My returns was 22%. It is low but very better than last experiment. Now I must distill Hg. I really afraid do it. I don't like do this in my small workshop!!! Topher said me before about that.
I will try distill Hg and melt it but I want to test chloride method that juan explained before. Maybe I will get better returns and remove Hg with wet method.

Thank you


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## tortuga09 (Jan 15, 2018)

Good evening
Every country has these rules and law on these precious metals
In Iran as in France there are laws
It's up to you to see how worked and what product


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