My New Silver Refinery - Thum Cell

[Alentia]

The next day I proceeded to filter liqued through coffee filters. This is a
very slow process, having to change filters 6 or 7 times. In my filters I thought I would have a lot more sludge, which I was told held all the silver. This material doesn't have any silver if I understand correctly now.
In the container I have a nice blue liqued. I added copper tubing to the solution and watched it start bubbling. This totally consumed the copper tubing I had added.Now I have poured that liqued through coffee filters. I saved all the filters with the sludge. I am going to burn of all paper
and sludge and hope that I have some silver.

Glen,

1. You are correct on first one, the sludge after Nitric processing most likely does not have any silver. (Unless you had not enough Nitric, as per below you had excess). In some cases if you have cobalt or any other metals more reactive than silver they may digest all Nitric and drop silver as cement, in this case that mud will have lots of silver. Please see below about H2SO4 use.
2. If your copper pipe dissolved in the solution, you have to feed more until it does not dissolve and there should be almost no bubbling (what you have is too much nitric in your solution)
3. Cemented silver should not look like sludge, but like a cement. You still have silver in the solution, do not proceed to "table salt" until your solution digest enough copper it is saturated with it and can not "eat" more of it.

I have recently processed prospectors silver ore. I would recommend to treat it with Sulfiric Acid before or in the middle of the process. Sulfiric acid will digest all the "other crap" if you use at the beginning. It will convert any nitrates developed back into nitric if you use it in the middle of the process. Wash well before and after changing acids.

Do not breath "brown fumes", even releasing them into atmosphere in Alaska is not so good idea. NOx is deadly.

 

[Platdigger]

Alentia,

I understand your post except for this line:

"do not proceed to "table salt" until your solution digest enough copper it is saturated with it and can not "eat" more of it."

Why keep adding copper when a small test could be made with salt or hcl to confirm if indeed there is any silver in solution?

 

[solar_plasma]

"do not proceed to "table salt" until your solution digest enough copper it is saturated with it and can not "eat" more of it."

Once I have precipitated silver from hot 4M HNO3/H2O2 1:1 with 2M HCl - no prob

I prefere HCl, because no unnecessary new ions are added and it's very precise, since it reacts that fast, so the last drop will not force further precipitate, only a chlorine-yellow tint occurs around the drop. Most in here know that, but I am just glad, when it happens, that I can take the chance to give a correct answer :lol: ....hey, there was something, I know about 8)

 

[Alentia]

Alentia,

I understand your post except for this line:

"do not proceed to "table salt" until your solution digest enough copper it is saturated with it and can not "eat" more of it."

Why keep adding copper when a small test could be made with salt or hcl to confirm if indeed there is any silver in solution?

If the idea to measure exactly how much silver is per weight, introducing AgCl into the solution will not help.

If the idea to see if there is any silver in the solution, NaCl can be used.

If all of the copper pipe was digested, it does mean either:

1. Nitric was in excess, but silver is present (no need for NaCl, keep digesting copper until silver starts to cement on the pipe)
2. No Nitric soluble metals are in the solution (NaCl test may help here)

 

[solar_plasma]

Alentia

If the idea to measure exactly how much silver is per weight, introducing AgCl into the solution will not help.

:shock:

Okay, so you mean AgCl-method is not quantitative or too complicated? But when you want to measure quantitative, cementing on copper won't be either, if you don't know if there are other dissolved metals than Ag with a lower electronegativity than Cu AND cementing will never give pure Ag. It's therfore we refine cementet stuff further. I don't know anything about ores, maybe this fact is negligible? If so, cementing may be easier.

Though I would prefere AgCl: neutralize if you want, drop, filter, wash with hot water, dry, weigh, and just to be sure: dissolve again, filter, dry, weigh, weight 1 minus weight 2
multiplicate with factor 0,7526251526251526

quantitative: yes (AgCl 1,88 mg/l)
complexity: a 14 year old child can do that (well I could, when I was 14)

...would be done within 1 hour

Dropping AgCl is the way to go, especially, if you want to measure exactly.

Please correct me, if I am wrong. Don't get me wrong, nonetheless I appreciate your skills! I know you are a thousand times more erxperienced than I am.

 

[g_axelsson]

I'm with Solar here. There is no need of extra copper in the solution unless you want to cement the silver on the copper.

Another way to do it is to use HCl to drop the silver as a precipitate and reuse the leach. If done correctly you could add just enough HCL to turn most of the silver into AgCl. The nitrate would turn back to nitric acid again and can be reused as a leach. The important thing here is that you should add just enough to precipitate MOST of the silver but not all. As long as you have a bit silver nitrate left there can be no free chlorides in solution. If you add too much HCL and use it for leaching the ore then it will turn the silver into silver chloride in the ore and you wouldn't get it out. But don't dispair if you have added too much HCL, just add a bit of silver nitrate dissolved in water until there is no more precipitate. Now all the free chlorine is gone.

Eventually the other metals leached from the ore will exhaust the acid and you will need to make more.

The silver chloride can be turned back into metal again via the sodium hydroxide / syrup method or other methods. It's all here on the forum.

But to economically extract silver with nitric acid from ore you have to have an extremely rich ore, highly concentrated ore or extremely cheap nitric. The NOx gases are also a problem, could be counteracted by adding hydrogen peroxide.

Welcome to the forum, Glen! 8)

Göran

 

[Alentia]

It might be a matter of personal preference.

I do not like dealing with AgCl due to the following reasons:

1. Too bulky by volume vs cemented silver
2. Requires extra steps
3. Almost impossible to get rid of Copper Nitrate with washes
4. Takes too long to settle after each wash

I am usually dealing with around 3-5kg of silver per batch, all of the above will introduce extra days for me. Washing Silver Cement with H2SO4 as I have described in another thread solves cement impurities issues.

 

[FrugalRefiner]

Though I would prefere AgCl: neutralize if you want, drop, filter, wash with hot water, dry, weigh, and just to be sure: dissolve again, filter, dry, weigh, weight 1 minus weight 2
multiplicate with factor 0,7526251526251526

I wouldn't advise members to dry their AgCl. When it dries it forms a crystaline structure that makes the conversion process more difficult and can result in loss of values. It can still be accomplished, but the crystal structure needs to be broken down to ensure complete conversion to metalic silver. It is better to keep your AgCl wet until it is converted.

After it has been converted to metallic silver, it can be dried and weighed (or melted and weighed) for a quantitative result.

Dave

 

[solar_plasma]

frugalrefiner

I wouldn't advise members to dry their AgCl. When it dries it forms a crystaline structure that makes the conversion process more difficult and can result in loss of values

Yes, convert it to AgOH and calcitate it, would be a way. But I thought the main goal was a quantitative test on silver, therefor drying and weighing without too many steps between. The loss you will have und calcination and melting, so from this point its not quantiative anymore.

 

[solar_plasma]

Alentia

1. Too bulky by volume vs cemented silver
2. Requires extra steps
3. Almost impossible to get rid of Copper Nitrate with washes
4. Takes too long to settle after each wash

I am usually dealing with around 3-5kg of silver per batch, all of the above will introduce extra days for me. Washing Silver Cement with H2SO4 as I have described in another thread solves cement impurities issues.

I was talking about a sample for testing, gramms not tons. For recovering ofcourse you take the easiest way, when ppm not matter.
With a vacuum pump this is done in minutes with samples up to 100g. It would be a nightmare to do this with 5kg silver, I guess.

Hey you guys are professional, I would expect, that you have better and more specialized lab inventory than I at school.

Washing Silver Cement with H2SO4 as I have described in another thread solves cement impurities issues.

For revovery and refining ingenious, but not quantitative analysis.

 

[FrugalRefiner]

Yes, convert it to AgOH and calcitate it, would be a way. But I thought the main goal was a quantitative test on silver, therefor drying and weighing without too many steps between. The loss you will have und calcination and melting, so from this point its not quantiative anymore.

I guess it's a matter of your point of view. From a theoretical point of view, any loss suffered during melting would affect the quantitative result. But from a real world point of view, you're going to melt it eventually, so any loss in melting reflects the true amount of silver you may be able to recover.

If I have a sample of material and I just create AgCl, dry, and weigh, I know what might be recoverable. But if I follow the process through to completion I know what can be recovered. There might be contamination in the AgCl. There might be some loss of values during conversion to metallic silver. There might be loss during the final washing and melting. So I might be dissappointed that what I calculated based on the weight of the AgCl is higher than the button I end up with after melting.

You are right that from a scientific perspective minimizing the steps involved in the analysis eliminates possible losses along the way. But what matters to me is the weight of the button or ingot I can hold in my hand after I've completed the process. It's just a different point of view.

Dave

 

[Glen Billeter]

Thank you to all:

I certainly see that I have a lot more studing to do or hire someone who knows what they are doing. lol

I was confused a little. I have 2 bottle of silver nitrate. I added more copper pipe to solution and it coninued to bubble. So I am assuming that the Nitric
was still present in the solution. I've let that sit for an extra day. Now I see
lots of white foamy stuff on top and some brownish sludge on the bottom.
This is out of 2 -5 gal buckets of ore. Test on this material have shown that there is between 50 - 200 ozs of Ag per ton of material. I don't need absolute results, just some stong indicators that , yes indeed, there is silver present. We also have about 10-15 grams of gold per ton. We have
approximately 70,000,000 yards of this material.

What I'm really not sure of is the best way to drop out the silver. I diluted
with a little distilled water. I wasn't sure if I added a little salt to solution
to drop silver or is there something else I need to do also. I was going to filter out silver and then burn off.

Thanks to anyone who can help.

Glen Billeter

 

[skippy]

Thank you to all:
Test on this material have shown that there is between 50 - 200 ozs of Ag per ton of material. I don't need absolute results, just some stong indicators that , yes indeed, there is silver present. We also have about 10-15 grams of gold per ton. We have
approximately 70,000,000 yards of this material.

Is that 70 million cubic yards? If the tests are representative of the whole 70 million yards, then you have many billions of dollars of metals and, yes, you should probably consider hiring serious professionals to help you. I am not a professional, but maybe you need a flunkie? :lol:

 

[Alentia]

Thank you to all:

I certainly see that I have a lot more studing to do or hire someone who knows what they are doing. lol

I was confused a little. I have 2 bottle of silver nitrate. I added more copper pipe to solution and it coninued to bubble. So I am assuming that the Nitric
was still present in the solution. I've let that sit for an extra day. Now I see
lots of white foamy stuff on top and some brownish sludge on the bottom.
This is out of 2 -5 gal buckets of ore. Test on this material have shown that there is between 50 - 200 ozs of Ag per ton of material. I don't need absolute results, just some stong indicators that , yes indeed, there is silver present. We also have about 10-15 grams of gold per ton. We have
approximately 70,000,000 yards of this material.

What I'm really not sure of is the best way to drop out the silver. I diluted
with a little distilled water. I wasn't sure if I added a little salt to solution
to drop silver or is there something else I need to do also. I was going to filter out silver and then burn off.

Thanks to anyone who can help.

Glen Billeter

Use salt only as indicator that there is still silver in the solution. As you would be normally proceeding by using copper cementation, do not even look at NaCl(salt) as your option for those quantities of ore.

Do not waste distilled water, you do not need it at this stage for silver.

The brown stuff you see at the bottom is your silver cement. Keep dissolving copper until reaction stops. Most likely you have other organic and inorganic matter in the bucket.

I would recommend following:

1. Let this batch run its course
2. Start new batch
3. Use about 1gl of ore, 1gl or water and 1/2gl of Sulfiric Acid - let it sit for 24 hours stirring once every 2-3 hours
4. Discard solution by decanting (let is settle on the angle - you can put it into another open bucket at 45 degrees)
5. Wash with regular water 3-4 times, settle and decant. no need to filter
6 Add another gallon of water to the ore
7. Add nitric to exactly as per estimated silver content. If you think you have 500gr of silver in 1gl of ore, add exactly 500ml of Nitric
8. Let it work its way through for about 24 hours, stirring occasionally
9. Let it settle and decant
10. Repeat step 5
11. Drop copper pipe into the decanted solution, you should have about 5gl of the solution based on all decanting sufficiently diluted with water
12. Add 1/2 of water to the remaining ore and about 200ml of H2SO4, let it settle for 24 hours
13. Repeat step 5 into new backet. Test with salt, it no silver present discard.
14. You may repeat step 7 with 1/5 of nitric used first time to see if there is still any silver left keep this one for at least 48 hours for full reaction.

When I mean discard it is worth while to treat solution with NaOH to pH 10 before discarding otherwise you may introduce some acid diluted metals, which should not get into close by rivers. Dissolved metals are poison to wild life and humans.

 

[Platdigger]

Sounds like a good ore to try thiosulfate on myself.
Sodium thiosulfate will take up silver without any additional chemicals.

 

[Alentia]

Sounds like a good ore to try thiosulfate on myself.
Sodium thiosulfate will take up silver without any additional chemicals.

Platdigger,

Can you please expand and explain?

 

[ilikesilver]

Thank you to all:

I certainly see that I have a lot more studing to do or hire someone who knows what they are doing. lol

I was confused a little. I have 2 bottle of silver nitrate. I added more copper pipe to solution and it coninued to bubble. So I am assuming that the Nitric
was still present in the solution. I've let that sit for an extra day. Now I see
lots of white foamy stuff on top and some brownish sludge on the bottom.
This is out of 2 -5 gal buckets of ore. Test on this material have shown that there is between 50 - 200 ozs of Ag per ton of material. I don't need absolute results, just some stong indicators that , yes indeed, there is silver present. We also have about 10-15 grams of gold per ton. We have
approximately 70,000,000 yards of this material.

What I'm really not sure of is the best way to drop out the silver. I diluted
with a little distilled water. I wasn't sure if I added a little salt to solution
to drop silver or is there something else I need to do also. I was going to filter out silver and then burn off.

Thanks to anyone who can help.

Glen Billeter

Just wanted to say, what a honor to have you on board!! thanks for joining, cant wait for the new season to start up, love the show. tim

 

[Glen Billeter]

Thanks everybody.
This has been quite an experience for me. I haven't had
to deal much with chemicals. In 1984 when I first started mining for gold,
I was in the jungles of Colombia, SA . As a rockie mining and in my excitement finding so much gold I wasn't very safe or smart. We used mercury for all our recovery and clean up. I didn't know it at the time, but after 6-7 years had gone buy, I become very sick and half crazy. A Doc. in Seattle who specialized in mercury, discovered that I had serviour mercury poisioning. It's taken almost 20 years but I finally am free of mercury. Now I feel a 100 times better, but my wife thinks I'm still a crazy gold miner. LOL. I use all safety gear now.

I want to learn as much as I can in a short time. I very much appreciate your
time, expertise, advice and friendship. I DO NOT plan on doing this full time for the mine. We will hire someone or sell the concentrates. The value is "through the roof". All I need is the simplist way to test ore in the field and come up with a value.
I'm starting to see some other operations , on Gold Rush and other places, that it looks like they are throwing away thousands of $ in gold and silver.
I want to show this and be able to prove quickly.

After using nitric and adding copper until all the bobbling was gone, I have been filtering off. Very slow process. It looked like a lot of sludge on the bottom, but it didn't show up in my filters. (That I could see anyway). I will burn that when I have a good curcible in a couple of days.
I was wondering after pouring off the liquid If I could add salt with HCL and zinc to see if there is any silver left. I don't know if this is a good idea.
Will I get the same reaction now that I have added copper or will that make a difference. Leaving the copper in doesn't seam to make a difference now.

I have some stainless pans and I was thinking about making one of those
Thum Cells to use on all the liquid left.

I think you are correct about the contaminats in the material. I will remove
the garbage on the next test with sulfuric acid. Then add the nitric and then the copper. Is there a good way to clean up all the liquid I have so I can drop the silver or is it a lost cause.
Also, should I heat the new material before starting and if so how hot should I get it. Should I repeat the heating in between steps after rinsing material.

Sorry about being long winded. I'm having way to much fun.!!!! 8)
Thanks for your response.

 

[4metals]

If all you want to do is get paid fairly for the value of the ore then why aren't you simply fire assaying the ore? Good sampling and sample prep and you know what you have. Anyone who is considering buying the ore to process will certainly be having it fire assayed first. (If he's not, send him to me, I have a bridge to sell him!)

If your buyer will be evaluating by fire assay, wouldn't you want the same benefit on your side of the transaction?

 

[Alentia]

Also, should I heat the new material before starting and if so how hot should I get it. Should I repeat the heating in between steps after rinsing material.

Heating ore will help to get rid of any organic matter, so you do not waste your acids. Otherwise, H2SO4 will take care of it. Drying and heating ore between acids will help, but not much, I would not waste any time.

Is there a good way to clean up all the liquid I have so I can drop the silver or is it a lost cause

If you referring to "current" batch you are processing and you had mention no effect on copper anymore. Whatever sediment you have at the bottom should be silver.