# Cloudy electrolyte



## MrCrusher (Nov 24, 2016)

Hi everyone.

I wanted to say thank you for the words of wisdom on my previous silver post.

I have now set up a silver cell and have a question.

When I dissolved my silver for my electrolyte the solution was much cleaner then I had expected. Once filtered to put into the cell it was crystal clear. As soon as the distilled water was added to it to get the volume up to the desired level in the cell the solution got cloudy. I now cannot see through it.

Could the cloudiness be due to temperature? It is fairly cool here in my lab ( hard to heat with the fume hood running) the solution is ~ 50 deg F That is an estimate as I do not have a thermometer to go that low.

If it is due to being too cool should I warm it up for a better growth of the crystals? Or is temperature not important for this process? I have searched the forum and have not found any mention of the temperature of a silver cell. 

Thanx
Mr_Crusher


----------



## kurtak (Nov 24, 2016)

Hmmm - are "sure" you used distilled water & not "purified" water

if it was purified water & not actually distilled it likely had chlorides in it & so formed silver chloride when you added it

I have had that happen because of not paying attention when buying my distilled water - grabbed a jug or two of purified (instead of distilled) because they are setting next to each other on the store shelf 

Kurt


----------



## MrCrusher (Nov 24, 2016)

Kurt,

I just double checked and all the jugs I have here are labeled Distilled. In fact to save on any mix-up's I have removed any other water from my lab it is so cheap its not worth a mistake.

However what you say makes sense. Humm if it was actually mis labled from he supplier what will this do to my cell. ( I am sure its not good )

Thanx
Mr_Crusher


----------



## MrCrusher (Nov 24, 2016)

Kurt,

I just checked it by lifting the cover. It has been going now for ~ 2.5 hours and while I can only see and inch or so into it the whole bowl is covered in crystals.

please don't tell me they will be contaminated  

Thanx
Mr_Crusher


----------



## FrugalRefiner (Nov 24, 2016)

I would shut down the cell and filter the electrolyte until it's crystal clear again. Clean up the bowl and start fresh. You can rerun any crystals that have already formed. Better to restart now than to run it for days and end up with a less pure result.

Dave


----------



## MrCrusher (Nov 24, 2016)

Dave,

While expecting a reply like this, I was hoping someone would say the chlorides would not cause an issue.

(Assuming that is what it is ) I guess you already know that filtering will remove those? If the solution will not filter clear I guess I will need to reprocess all the silver in the solution and start again?

and BTW Happy Thanksgiving everyone.

Mr_Crusher


----------



## goldsilverpro (Nov 24, 2016)

MrCrusher said:


> Kurt,
> 
> I just checked it by lifting the cover. It has been going now for ~ 2.5 hours and while I can only see and inch or so into it the whole bowl is covered in crystals.
> 
> ...


Are you using a stainless bowl? Do you mean metallic silver crystals or non-metallic silver nitrate crystals? What type of silver did you use to make up the solution? How much silver/liter? What type of silver are you using as the anode?

-50F is quite cool, although the internal resistance should raise the solution temp. Did you check the temperature after running for 2.5 hours? In the literature, it says the operating temp is between 80-120F, although it doesn't say it has to be in that range. I have never run the solution at -50F. My guess is that it would still work, but maybe not as efficiently.


----------



## FrugalRefiner (Nov 24, 2016)

If it is silver chloride, the chlorine would volatilize when you melt, but it might take a bit of silver with it. But if it's something else, who knows?

If it's very fine it may not filter out well on the first pass through the filter. Just pour the filtrate back through the same filter again until it becomes clear. As the larger particles clog the pores of the filter paper, the remaining pores become smaller and smaller and should eventually do the job. An alternative would be to allow the electrolyte to sit undisturbed until the precipitate settles, then syphon or decant off the clear solution.

Dave


----------



## goldsilverpro (Nov 24, 2016)

If it is silver chloride from chlorides in the water (or in the nitric), I wouldn't worry about it.


----------



## MrCrusher (Nov 24, 2016)

the details as asked.

first it is a Stainless steel bowl
the solution was made from silver I processed
I used 400 grams to make the solution when the solution was finished I added about 5 grams to make sure I used up all the nitric.
After being on heat at about 160 deg F for 12 hours there was still a very small amount of silver in the solution. This I would think meant I had used up my free nitric.

Then the solution was filtered and added to the stainless steel pot. I then added the distilled water which is when the solution got cloudy.

When looking into the pot now it is silver metal crystals.

Also it is About 50 deg F not -50F ( I use the tilde for saying about I will stop doing that )

I melted my processed silver for the anode . I am using the same basic set-up as Sreetips video.

Thanx
Mr_Crusher


----------



## goldsilverpro (Nov 24, 2016)

Sounds fine. I think you did a good job. 

A tiny amount of silver chloride looks like a lot. I have had it in cells before due to nitric cross-contaminated with a little HCl - my worker wrongly used the same drum pump for HCl and HNO3 - contaminated the whole drum of nitric.

A couple more questions.
What is the solution volume? How much current are you using? 

Is your silver crystal stringy and/or fluffy or is it short and dense? If stringy and/or fluffy, I would advise dissolving and adding about 5-10 g/l of copper. Copper house wire is quite pure. It takes about 4.15ml of 67% nitric plus 4.15ml distilled water to dissolve a gram of copper. A short, dense crystal filters and rinses much better and, also, you have to harvest a little less often in order to prevent shorting of the crystal to the anode.

NOTE: Since you're using stainless, I would certainly check out Palladium's videos.

http://goldrefiningforum.com/phpBB3/search.php?keywords=stainless+silver+cell&terms=all&author=palladium&sc=1&sf=all&sr=posts&sk=t&sd=d&st=0&ch=300&t=0&submit=Search

I use the tilde for "about" or "approximately" also, but it is quite small in this particular type style.


----------



## MrCrusher (Nov 24, 2016)

The crystal is dense and clinging to the bowl nicely here is a picture of the voltages and the bowl.






The volume is about 4 liters. Before I started I checked to see how much total I needed to fill the bowl.
It was around 3850ml that is how I came up with the 400 grams of silver for my starting solution. As I have seen it mentioned to use anywhere between 75 and 150 grams per liter of solution depending on who is giving the information.

For me to logically process that information and make my own judgment I thought the process replaces the contaminate with the silver in the solution and leaves the contaminate in the solution. To me logically that would mean the exact concentration of the solution is not critical which would explain to me why it varies from one person to another.

If I am off base here please enlighten me.

Thanx
Mr_Crusher


----------



## goldsilverpro (Nov 25, 2016)

You seem to be doing everything right. The volts are falling between 3 and 4, which is right on. At 1.8A, you'll produce about 7g of silver crystal per hour. 

You can raise the amps a bit, but I would not exceed 4V. When running large 30 gallon Thum cells, I used about 8A per gallon (~4 liters) of solution and about 3.5V. However, in a Thum cell, the anode area is quite large, about 60% of the cathode area. In the bowl setup, the anode area is quite small, probably less than 10% of the cathode area. This will provide more resistance (relatively) and will give a higher voltage per amp.


----------



## Palladium (Nov 25, 2016)

Looks good to me to. Did you wash the bowl just before using it and what was your source for the silver that you made the solution from ( cemented silver or crystals).


----------



## MrCrusher (Nov 25, 2016)

Thank you all for the feedback.

Yes I washed the bowl before the start as I do with my beakers I use Bon Ami and wash twice. I myself have also found NEVER touch the inside. Once washed ( I have to do that in the kitchen no running water in my lab) I take them to my lab and rinse the insides with Distilled water if I notice any water beading I take them back in a wash again. Once rinsed with distilled water I place in covered draining rack upside down to dry. Or most times I put them into use immediately.

The exact source of my starting silver was some I processed. I used cementing to copper but I found for me at least to be much more problematic then using salt then rinse then use Lye and sugar method. I have also found that process to rinse easier. I guess to each their own. 

an update on the cell. The cloudiness is gone now here is a picture.



now for me at least the question is . . . If it was a chloride causing the cloudiness has it settled or been used up in my crystal's?

Thoughts?

Thanx
Mr_Crusher


----------



## goldsilverpro (Nov 25, 2016)

Probably settled, although I guess some could be occluded in the crystal.


----------



## MrCrusher (Nov 28, 2016)

Thanx for the advice one last question.

Do you normally run the cell until it shorts out, and blows the safety fuse or
when it is getting full?

My solution is still crystal clear no color at all.

Thanx
Mr_Crusher


----------



## FrugalRefiner (Nov 28, 2016)

Don't let it short out! If it does, it will probably burn a hole through the anode bag and allow some of the slimes (contaminants) to mix in with your newly refined crystals. Shut it down when it starts to get full, harvest the crystals, and restart it.

Dave


----------



## MrCrusher (Nov 28, 2016)

Dave

Thanx for the quick reply.
I am shutting it down sure don't want to risk that.

Thanx
Mr_Crusher


----------



## g_axelsson (Nov 28, 2016)

Dave beat me to it... but I've already written it.  

You don't want the cell to short out, that might burn a hole in the anode bag and let out some of the anode slime, contaminate your silver crystals.
If your feed stock is very clean you can run longer than if you run dirty silver. As I understand it, the limiting factors are usually too much copper or lack of silver in the electrolyte. You should also look out for palladium, easily spotted as the electrolyte turns greenish and easily tested and removed with DMG.

A lot of links at the bottom of http://goldrefiningwiki.com/mediawiki/index.php/Silver_cell

Göran


----------



## MrCrusher (Dec 4, 2016)

Thanx again everyone for the advice.

I now have another question.

After a full cleanup and filtering of my solution I am ready to restart the cell however, how can I tell the concentration of my electrolyte? After reading many other silver post it looks like amperage is effected by the solution concentration? If so can the electrolyte be too concentrated? 

As a side note my first cleanout produced 24.4 ozt I also got a few very large crystals the biggest one weighs .6 grams is there a way to make more larger ones like that? I have looked around and found a thread on it, but it did not seam to come to a resolution on the topic.

Thanx guys your support is invaluable for us noobs.

Mr_Crusher


----------



## Topher_osAUrus (Dec 4, 2016)

I haven't yet done any silver cell runs, I am still in the learning phase... But, this book -Electrolytic Separation: Recovery & Refining of Metals -theoretical and practical by G. Gore..... He goes into the crystal structures formed in different concentrations of silver nitrate solution (amongst a great many other detailed things)

I have attached a couple pictures for reference... Hope it helps


----------



## goldsilverpro (Dec 10, 2016)

MrCrusher said:


> Thanx again everyone for the advice.
> 
> I now have another question.
> 
> ...


Keep in mind you don't need extreme accuracy in the following methods of determining the silver content of the solution.

You can get a ball-park idea of the silver concentration by keeping records of the following and doing the calculations. However, this method assumes good efficiency at both of the electrodes and a proper setup. For example, if the mesh of the anode bag is too tight, the silver in the solution can be depleted very rapidly.
(1) How much Ag was in the solution to start with.
(2) How much copper has dissolved into the solution. Copper is the most common metal associated with silver scrap. For sterling silver, assume the copper content is 10 percent. For Ag that has been cemented with copper and melted into anodes, I would assume the copper content will be between .5 and 2.0 percent (usually around 1 percent). For each gram of copper dissolved, the Ag content of the silver in solution will be reduced by 3.4 grams.

For more accuracy, there are several titration methods. 
(1) The Ag can be analyzed by the Volhard titration method. Search the forum for this method.
(2) Here's one I just thought up and have not seen in print (although, due to it's simplicity, someone has surely thought of it). Precipitate the silver as silver chloride, in a small known quantity of solution sample with an excess of standardized HCl (also of a known quantity), **remove the AgCl by filtration, and then back-titrate the excess HCl with standardized NaOH solution and one of several available indicators. I've never used this method but, once you're set up for this, I think it would be super simple and reasonably accurate. 
(3) Guy-Lussac method. Never cared much for this method - too slow and tedious for me. The U.S. Mint used it and it is quite accurate.

** I don't know if this filtration step is necessary. I included it because of the possible reaction of the NaOH with the AgCl.
However, since this all takes place on the acid side, the NaOH probably reacts preferentially with the HCl. I would use an indicator that changed colors at a pH of around 4.

Fire assay would work.

For a gravimetric method, you could precipitate the silver, as the chloride, with salt solution or HCl, then collect the AgCl, rinse it well, dry it, and weigh it.

If you have an AA or know a lab with an AA, that is a quick and easy way to analyze the silver.

There are other methods in the literature.


----------



## MrCrusher (Dec 19, 2016)

Thank you for the reply.

Due to my limited knowledge I evaluated what you said and did the following;

I wanted to lower the volume I had of electrolyte. I had 4000ml and did not want to try and decant into the bowl with the 5000ml beaker that was so full. So I removed 1000ml because it would make my calculations very simple. I knew I started with 100 grams per 1000ml. I then turned that back into silver powder using the salt and lye, sugar. I ended up with 87.3 grams of silver after rinsing and drying.

My question now is, I recovered 24.4 ozt of silver from my cell so I used up about 50.8 grams from my electrolyte. Is that a normal amount to consume from the electrolyte?

I want to run the cell to do much more (about 80 ozt ) I was going to increase the concentration of my electrolyte for this run to 150 grams per 1000ml. If I use the same ratio of silver from my electrolyte I should have about 435 grams left in the electrolyte when finished.

While I admit I did not use any exact process you recommended I felt what I did was logical.

If I did something very wrong please enlighten me. And if you see something wrong with my calculations any insight would be appreciated.

Thanx
Mr_Crusher


----------



## FrugalRefiner (Dec 19, 2016)

The relationship between your starting silver concentration / amount of silver processed / ending silver concentration is directly related to the contaminants in your feedstock.

The main contaminant is usually copper (assuming you're processing sterling, coin, etc.). Each gram of copper that goes into solution will displace 3.4 grams of silver. The purer your feedstock, the less silver displaced.

If you run pure silver through a cell, the ending concentration of the electrolyte will be about the same as the beginning concentration (allowing for evaporation, side reactions, etc.) If you run sterling silver, for every 100 grams of sterling you run, the silver concentration of your electrolyte will drop 25.5 grams (100 grams * 7.5% copper content * 3.4 grams silver displaced for each gram of copper dissolved).

Dave


----------



## Palladium (Dec 19, 2016)

[youtube]http://www.youtube.com/watch?v=CC9LO5WnuvU[/youtube]


----------



## geedigity (Dec 20, 2016)

Thank you for the video. You did a good job of explaining how to determine the life expectancy of the silver cell solution in very simple terms.


----------



## MrCrusher (Dec 20, 2016)

Dave,

I understood those factors however maybe what I was asking is much more specific to the overall setup.

Goldsilverpro said this;

You can get a ball-park idea of the silver concentration by keeping records of the following and doing the calculations. However, this method assumes good efficiency at both of the electrodes and a proper setup. For example, if the mesh of the anode bag is too tight, the silver in the solution can be depleted very rapidly.

The colored part is what I am getting confused about here is why.

All of my feedstock is very clean It was all processed with the salt, lye. sugar method after dissolving in the nitric. I have seen it stated that process itself should make .999 silver. When I make my shot with it my melt dish stays very clean and I don't have anything floating on the molten silver.

Considering I know I have clean feedstock I thought the usage of silver from the solution was high. another reason I think this is because after it was done the 24toz the solution has no color to it at all. ( which from what I have seen most contaminants would add some color to it )

Maybe what I am asking is will the efficiency improve is the anode and cathode size are more equal?
Am I just being too picky?

Palladium,

Thank you for all of your You tube videos, I think I have watched them all at least 2 times some more. They are a bit long winded but VERY informative.

the one you posted the link to here I have watched many times I get the principles, However the way I understand it from that video is a transfer of contaminants into solution and silver out. I would think if I put 50 grams of contaminants into the solution it should have some color to it, but it is crystal clear.

Hopefully I have explained my confusion better thanx all

Mr_Crusher


----------



## FrugalRefiner (Dec 20, 2016)

MrCrusher said:


> Dave,
> 
> I understood those factors however maybe what I was asking is much more specific to the overall setup.
> 
> ...


To operate properly, there has to be a continuous flow of silver ions from your anode to the cathode. If the fabric of the anode bag is a very loose weave (like burlap) some of the undissolved material (the slimes) will pass through the fabric's pores and contaminate the crystals. On the other hand, if the fabric is a very tightly woven fabric, it can inhibit the passage of silver ions. Even though they dissolve from the anode, they can't pass through the bag fast enough to travel to the cathode at the same rate they're being deposited. You end up with a high concentration of silver ions inside the anode bag, and a low concentration outside the bag at the cathode. So the cell loses efficiency.



> All of my feedstock is very clean It was all processed with the salt, lye. sugar method after dissolving in the nitric. I have seen it stated that process itself should make .999 silver. When I make my shot with it my melt dish stays very clean and I don't have anything floating on the molten silver.
> 
> Considering I know I have clean feedstock I thought the usage of silver from the solution was high. another reason I think this is because after it was done the 24toz the solution has no color to it at all. ( which from what I have seen most contaminants would add some color to it )
> 
> ...


Have you checked your slimes yet? You may find some silver there. As the anodes dissolve, tiny bits of silver become detached and fall into the slimes. Once they detach from the anode, there is no electrical force acting upon them to cause them to dissolve, and the nitric level is so low they can remain undissolved.

Dave


----------



## MrCrusher (Dec 21, 2016)

Dave,

Thank you very much. I am a mechanical person and never thought of it like that, I think that was just the way to express it to me for my understanding.

Thanx
Mr_crusher


----------



## FrugalRefiner (Dec 21, 2016)

From one mechanical person to another.  

Glad it helped.

Dave


----------

