# Silver Electrolytic Cell Volume



## kadriver

Lazersteve:

I have alot of silver that I want to process in an electrolytic cell (over a pound of dried, cemented silver powder).

Your DVD "Silver, A to Z" gives specific directions for a 1000 ml cell.

Would it be possible to increase the volume to 2000 ml by just doubling the amount of electrolyte - ie, 200 grams silver powder, 234 ml nitric acid, and then enough distilled water to bring the total volume up to 2000 ml in a 2000 ml container?

By making the cell larger, I could made the anode basket & filter bigger and install more anodes - plus reduce the amount of time harvesting & cleaning the cell.

Also, I am going to use cememnted silver for the electrolyte. First I will boil the cememnted silver in Hydrochloric acid to remove impurities. Then I will dissolve the cememted silver in nitric acid. Then filter to remove gold or platinum that may be present and then proceeed with the cell construction.

I also want to remove any lead or tin that may have made it into my cememnted silver. Is there a process for doing this?

When harvesting the silver crystals from the cell, I plan on filtering the electrolyte. But I will not let the silver crystals make it into the filter.

Instead I will leave the crystals in the container after pouring off the electrolyte into the filter. To remove any electrolye still clinging to the crystals, I will wash the crystals over and over in boiling water, pouring the water off each time, into a filter paper if necessary, but not letting any of the crystals enter the filter paper. Then dry and melt.

Please correct me if I have made any errors to the above process.

Thanks so much for your help.

kadriver


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## lazersteve

kadriver said:


> Would it be possible to increase the volume to 2000 ml by just doubling the amount of electrolyte - ie, 200 grams silver powder, 234 ml nitric acid, and then enough distilled water to bring the total volume up to 2000 ml in a 2000 ml container?



Yes, be sure to maintain a 4" anode to cathode spacing. Also the cathode should be no more than twice the area of the anode



kadriver said:


> Also, I am going to use cememnted silver for the electrolyte. First I will boil the cememnted silver in Hydrochloric acid to remove impurities. Then I will dissolve the cememted silver in nitric acid. Then filter to remove gold or platinum that may be present and then proceeed with the cell construction.



I would not boil the silver in HCl. I would use water instead. Wash with boiling water until a sample of the filtered water no longer turns blue when tested with ammonia hydroxide.



kadriver said:


> I also want to remove any lead or tin that may have made it into my cememnted silver. Is there a process for doing this?



Silver cemented with copper should not have any of these in it as copper will not cement tin or lead out of solution. Refer to the activity series chart on my website or wiki.



kadriver said:


> When harvesting the silver crystals from the cell, I plan on filtering the electrolyte. But I will not let the silver crystals make it into the filter.
> 
> Instead I will leave the crystals in the container after pouring off the electrolyte into the filter. To remove any electrolye still clinging to the crystals, I will wash the crystals over and over in boiling water, pouring the water off each time, into a filter paper if necessary, but not letting any of the crystals enter the filter paper. Then dry and melt.



If you can get a cell resistance of 1 or two ohms and push enough amps through the solution, you should get hard crystals that will be easy to rinse. Optimium voltage is 3-4.4 volts.

Steve


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## kadriver

Thanks!


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## kadriver

I have hit a snag trying to get this silver cell running.

Before I was able to read the post, I went ahead and treated my cemented silver powder by boiling in HCl - what a mistake!

After boiling in hydrochloric acid, I washed many times using hot tap water, and then two final rinses in boiling distilled water.

I noticed that some of silver powder had formed small clumps after all this and I tried to break them up as much as possible.

I knew I was in trouble when I smashed one of the larger lumps, about 1/4 inch, and it broke apart. The inside was a darker color than the rest of the washed silver powder.

I dried the silver powder completely - along with the lumps.

I went ahead and dissolved the 210 grams of powder (with some lumps still in it) in 235 ml nitric acid and 235 ml distilled water. It came out looking real good, completely dissolved, clear with a slight yellowish tint.

Then I went to filter and as soon as the silver nitrate hit the filter paper it got cloudy. The filter paper was moistened with distilled water & I am very careful not to use tap water when working with silver nitrate.

I figured the Hydrochloric Acid was to blame. I did not know what to do, so i decided to start over.

I added Hydrochloric acid to the silver nitrate and precipitated out all the silver chloride until no more would come out.

I washed the silver chloride in plenty of hot water, then added NaOH to turn it into silver Oxide. Then i added sugar and precipitated out the silver metal. Washed & dried and started all over again.

This time I dissolved the precipitated silver in more nitric acid - no problem (except that at first the 35% acid started to turn purple - then it cleared up nice and clear with some silver chloride on the bottom of the container).

I went to filter and got cloudy solution again.

I filtered a couple of times but the cloudiness would not filter out.

I poured the cloudy silver nitrate into two beakers (see photo) and i will allow them to sit to see if this cloudiness will settle out.

IF it does, then i will siphon off the silver nitrate and proceed from there.

Can anyone give me some guidance on what to do next.

I will never put cemented silver in Hydrochloric acid again!

Thank you - kadriver


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## lazersteve

Gently heat the cloudy solutions to 40-50C and the solids should either dissolve (if a nitrate) or settle out (if a chloride) after they are heated for an hour or so.

Steve


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## kadriver

Here is what the solutions looked like after settling for about 4 hours.

The tall beaker was cloudy from top to bottom.

The smaller beaker was beginning to get clear at the top.

Both beakers appear to have some precipitate collecting at their bottoms.


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## kadriver

Here is another shot of the smaller beaker - note the white precipitate at the bottom.

Also:

i heated the tall beaker to 122 degrees F (50 C)

There was no change in cloudiness and no precipitate.

I continued to heat the tall beaker up to 160 degrees F.

The solution got a little clearer, but still remained cloudy.

I plan to let then both settle over night.

If they both settle out completely, then I will siphon off the clear liqiud only and use this in the cell.

OR

I will siphon off the clear liquid and cement out the silver and make anode bars with it.

Then I will use the 999 silver bar i have to make electrolyte for the cell and forget about using cemented silver in the cell.

Any input from the forum is welcome - Thank You

kadriver


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## Harold_V

There's nothing wrong with washing cemented silver with HCl---but as I've said many times before, without incineration, I don't give a damn what anyone says, there are residues that are never removed, and you pay for them with grief. 

If you'd like to start your cell using cemented silver, no problem. Just _*melt it first*_, then dissolve the resulting corn flakes. You likely will still have traces of substances that aren't desirable, however. I had a strict policy of using silver crystals for my electrolyte, although I have no recollection how I got the first batch of crystals. Probably dissolved some of my cement silver! 8) 

Harold


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## kadriver

Harold:

Is the precipitate in these beakers silver chloride? I suspect that it is. Is there a test to determine if it is in fact silver chloride?

Assuming that the precipitate in the photo is silver chloride, will melting the silver (incinerating) effectively remove the silver chloride?

If so can someone breifly explain the chemical process? Will the entrapped silver chloride turn to silver oxide once heated? Is silver oxide soluable in water?

I need to take a basic chemistry class at our local community college.

My plan is to cement out the silver from this cloudy batch of silver nitrate. Then I will melt (incenerate) the silver and make cornflakes. Then I will dissolve the cornflakes in nitric acid and go on from there to build the cell.

As a precaution - learned from Hoke - before dissolving the whole batch in nitric acid, I will dissolve a small amount of the melted & cornflaked silver in a test tube. Then I will add some distilled water a drop at a time and see what happens.

If this test produces cloudy silver nitrate as before, then I will not use this batch of silver for the cell. I will melt it into anode bars. 

Then I will use the 999 silver bar that I have to make silver nitrate crystals and use those crystals for the cell.

I am still learning.

Thanks for your help - I felt lost yesterday, but today I feel I have some new direction.

kadriver


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## kadriver

Harold was right on the money - again.

I cemented all the silver out of the cloudy silver nitrate.

I dried the silver powder.

I melted some of the powder saved some and set it aside - unmelted

I then took a small amount of the unmelted silver powder (cemented from the cloudy silver nitrate) and put it in a test tube (about 1/2 gram).

I took a small amount (about 1/2 gram) of the silver that had been melted (incinerated) and put it in a different test tube.

I then added 2 ml of nitric acid and 2 ml distilled water to each test tube.

The powder dissolved right away when heated (less than 1 minute).

The melted silver shot took quite a bit longer with plenty of heat to dissolve.

Once both were completely dissolved I set both test tubes side-by-side and they both looked identical - clear.

Then I added about 2 more ml of distilled water to each.

After adding the distilled water, the un-incinerated dissolved silver powder turned cloudy (the sample on the left in the photo).

The incinerated silver shot remained clear (the sample on the right in the photo).

The clouds have parted and i am back in business - what a learning experience.

Thanks to Harold for this important tip:

If you treat your cemented silver by boiling it in hydrochloric acid to remove metals such as zinc or copper - be sure to INCINERATE the powder after the HCl bath.

I would still be going around in a circle trying to get the cloudiness out of my silver nitrate. This forum is priceless!

Thanks to all - kadriver


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## kadriver

I finally got the silver cell running - what a sight!

I am convinced I would still be trying to figure out a way to get rid of the chloride in my electrolyte if not for the help of Harold & Lazersteve - Thanks you guys.

As you can see by the pictures - the electrolyte was as clear as could be after i inceinerated the silver that had been treated with hydrochloric acid - what a simple fix.

I followed the DVD instructions as closely as possible and i got perfect results - If you want to refine 999 silver, then get Lazersteves DVD and follow it because it works.

I used a cloth (not paper) filter bag for vacuum cleaners from lowes for the filter bag to hold the slimes from the anode bars. As a test, I cut a small piece of the filter bag & placed it in a test tube with 50/50 nitric acid/distilled water over night to make sure that is would hold up to the acid.

I have a question:

It got late, so i unplugged the cell and walked away - is it ok to leave the cell completely assembled for overnight storage, then just plug it back in tomorrow morning?

Another amazing event for me in the refining of precious metals - watching these crystals grow was facinating.

Thanks to this forum for all your help.

kadriver


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## Oz

That is a fine achievement, congrats. 

However I would not re-start that cell until you have knocked down the silver or harvested it. If your crystaline silver reaches your anode bag it will short the cell and cause a perforation that mixes your contaminates with your refined silver. Then you would be back to square one. 

As a by-the-way, your silver looks thready to me given the mass. What are your cells parameters? 

I cannot reply specifically as to Steve's DVD but am making comments based on the silver cells I run.


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## HAuCl4

8)


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## kadriver

Oz, I will ensure the crystals are pushed down before I restart.

I checked volts and amps:

battery charger set on 12 volts - meter reading on the actual output during cell operation was 8.6 volts.
actual amp reading during operation was 6.8 amps throught the cell.

I used the lower 6 volt setting early on. The crystal growth was slow, and I only had about 4 amps going throught the cell.

As soon as I switched to 12 volts, the amps increased and the crystal growth became rapid to the point where i could watch the crystals grow.

Will the thready look of the crystals be a problem in some area I am not familiar with? Should I reduce the setting from 12 volt to 6 volts? If thready crystals are ok, then I would prefer the 12 volt setting as the crystal growth was much greater.

Thank you for the input - kadriver


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## Barren Realms 007

kadriver said:


> Oz, I will ensure the crystals are pushed down before I restart.
> 
> I checked volts and amps:
> 
> battery charger set on 12 volts - meter reading on the actual output during cell operation was 8.6 volts.
> actual amp reading during operation was 6.8 amps throught the cell.
> 
> I used the lower 6 volt setting early on. The crystal growth was slow, and I only had about 4 amps going throught the cell.
> 
> As soon as I switched to 12 volts, the amps increased and the crystal growth became rapid to the point where i could watch the crystals grow.
> 
> Will the thready look of the crystals be a problem in some area I am not familiar with? Should I reduce the setting from 12 volt to 6 volts? If thready crystals are ok, then I would prefer the 12 volt setting as the crystal growth was much greater.
> 
> Thank you for the input - kadriver



The crystal growth looks good, Mst of the recomdations is for your voltage to be around 3V. I am not shure if the higher voltage will cause problems.

I am interested in your anode bag and what if any slimes are in it. With your solution it looks like you silver was pretty clean.

Thanks


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## lazersteve

I mentioned on the DVD that the thread like crystals are typically due to excessive cell voltage. A trade off of using the lower voltage is the slower crystal growth due to the decreased amperage flow in the cell. To get a higher amperage flow at lower voltages requires more silver in the electrolyte, changing the anode to cathode spacing and or size ratio, or using some added copper in the electrolyte which I also mentioned on the DVD.

By doubling the silver concentration in the electrolyte (e.g: 200 g / liter) you should see an increase in the current flow at lower voltages and hence more dense crystal growth. As a side note silver nitrate has a solubility limit of 2.16 kg/L in water at 20C, this equals 1370.74 g of silver per liter as a theoretical maximum silver concentration in the electrolyte*.

The more dense your crystal growth the easier the cell clean up will be since the tree like crystals tend to hold some of the electrolyte and will require good rinsing as demonstrated on the DVD. Dense crystals are easier to harvest and rinse.

Too much voltage can lead to contamination engrained in the crystals due to the fact that a wider variety of metals will be deposited on the cathode over the wider voltage range. Silver grows in the 3-4 volt range as the voltage increases other metals will be more likely to co-deposit with the silver.

Addition of a small amount of tartaric acid also may aid in growing denser crystals.

Here's a link to some information I found on the net concerning silver cells:

Silver Cell Parameters

The crystals that grew in my cell were very stiff, but still tree like. They rinsed very easily and melted with no red fumes ( nitrogen oxides = NOx). 

In short low voltage at high amperage is most conducive to pure, hard, dense crystal growth.* 

Steve

*= Edits


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## Barren Realms 007

lazersteve said:


> I mentioned on the DVD that the thread like crystals are typically due to excessive cell voltage. A trade off of using the lower voltage is the slower crystal growth due to the decreased amperage flow in the cell. To get a higher amperage flow at lower voltages requires more silver in the electrolyte, changing the anode to cathode spacing, or using some added copper in the electrolyte which I also mentioned on the DVD.
> 
> By doubling the silver concentration in the electrolyte (e.g: 200 g / liter) you should see an increase in the current flow at lower voltages and hence more dense crystal growth.
> 
> The more dense your crystal growth the easier the cell clean up will be since the tree like crystals tend to hold some of the electrolyte and will require good rinsing as demonstrated on the DVD. Dense crystals are easier to harvest and rinse.
> 
> Too much voltage can lead to contamination engrained in the crystals due to the fact that a wider variety of metals will be deposited on the cathode over the wider voltage range. Silver grows in the 3-4 volt range as the voltage increase other metals will be more likely to co-deposit with the silver.
> 
> Addition of a small amount of tartaric acid also may aid in growing denser crystals.
> 
> Here's a link to some information I found on the net concerning silver cells:
> 
> Silver Cell Parameters
> 
> The crystals that grew in my cell were very stiff, but still tree like. They rinsed very easily and melted with no red fumes ( nitrogen oxides = NOx).
> 
> Steve



Thanks that kind of what I thought would happen with the higher voltage.


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## kadriver

I only have two settings on my charger. I lowered the setting to 6 volts with about 4 amps going throught the electrolyte.

The crystals were very different, smaller with less length more like little moss trees.

I will leave the setting on 6 volts and just add some patience. I want to let the anodes dissolve completely before I harvest the crystals.

I used 3 - 2 troy ounce bars, plus one bar on top with a hook welded in place to catch the copper cross member. 4 bars total in the basket.

Only two of the 4 bars is submerged in the electrolyte inside the filter bag.



Barren Realms 007 said:


> The crystal growth looks good, Mst of the recomdations is for your voltage to be around 3V. I am not shure if the higher voltage will cause problems.
> 
> I am interested in your anode bag and what if any slimes are in it. With your solution it looks like you silver was pretty clean.
> 
> Thanks



The silver crystals are just plain beautiful - I can't quit looking at them.

The bag is all I could find that fit the description given in the DVD.

I am not sure of the material content of the bag.

I bought it in the vacuum filter replacement area at Lowes.

It is a synthetic cloth that resists the acid pretty well.

The bag is starting to get black debris collecting plus black specks floating on top of the liquid in the bag.

I will get a photo of the slimes and post it later on.

I am having much fun with this new toy.

Thanks - kadriver


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## metatp

lazersteve said:


> Addition of a small amount of tartaric acid also may aid in growing denser crystals.


 Has anyone tried tartaric acid and want to share their findings?


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## Oz

I have not tried it yet, but I do not have problems in getting nice compact crystal growth. I have also stayed away from it on the premise that it would be just one more potential contaminate. Not that I have read anything that says it would be a problem.


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## 4metals

I have a client who has a cell which has been producing for a year now but he spaced the basket (it's a Thum cell) too far from the cathode (6") and when I was in to see him, coincidentally on a day when he had the cell broken down to change the electrolyte, I pointed out the problem. He has since made the distance 4" and the cell draws less volts but the silver grows faster and more spindly and needed more attendance. 

Tartaric acid additions, small just a few grams, made the crystals denser and bought him more time between scrapings. The crystals were more stout as well, much more dense.


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## shyknee

hi 4 metals did they look like this? i am just wondering if they where thicker


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## stihl88

Can someone explain as to why the Silver crystals don't re-dissolve back in to the solution once they have been electrically precipitated as crystals.
Is it that all of the HNO3 is expected to have been used up in the initial manufacture of the AgNO3 electrolyte? If so i would imagine it would be fairly crucial to get the initial HNO3/H20 to silver ratio fairly correct when making the AgNO3 electrolyte to prevent the repetitive dissolution of the crystals upon their development.

Sorry for the what is likely a simple Question, but I'm quite interested in this Silver refining via crystal method and some simple things need clarifying for me sometimes.

Regards

Stihl


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## kadriver

I am just like Stihl - I was wondering the same thing. Those crystals are very thin and it seems that even a little nitric acid would dissolve them easily.

I would also like to know what is going on inside that cell. I can observe a flow of some sort of wavey pattern dropping down from the bottom of the basket, while I see occasional bubbles rising to the surface.

Can some one describe briefly what is happening inside the cell.

Shyknee, those crystals in the blue glove are unbelievable - how can I get mine to grow like that?

I have included a photo of the inside of the first filter bag I used. I was using cememnted silver bars for anodes - not much in the way of deposits from those bars.

I was going to dissolve a stering silver bowl and cememnt the silver when I realized that all I had to do was melt the bowl and pour a bar for an anode. Of course when i put this melted sterling bar in, the electrlyte began to turn blue green.

There is only about 4 inches from the top of the crystal growth to the bottom of the basket.

Since putting in the impure bar the filter bag has gotten much dirtier with black residue.

The power supply is set on six volts, but only about 4 volts on my meter. The amps are about 4.8 or so. The crystals look real good now and i am happy with the way it is running.

Soon I will have my first 999 pure silver bar.

Thanks - kadriver


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## butcher

Here is how I understand it? 
The external DC current oxidizes the silver anode (with nitrate anion in its vicinity), it gives up its electron, and becomes a cat ion in the electrolyte (silver nitrate solution), this cat ion is in solution, 

at the same time on the other side of the cell near the cathode, the silver nitrate electrolyte around the cathode (silver from solution) is reduced gaining an electron changing this back to the silver metal, this is formed from the electrolyte and not the same silver cat ion that left the anode, depending on conditions the silver electrolyte is a certain concentration of silver cat ions and nitrate anions (nitrate anion which migrate to anode to get another silver cat ion keeping same amount of silver to nitrate concentration to the solution), this will stay the same concentration no matter how much silver dissolves or plates out (temperature or PH may change things some) but silver to nitrate ratio basically stays the same (inert anodes can change this but that is a whole another story).

I am not that smart about this but I believe the original electrolyte mix will determine resistance of cell, PH, metal concentration and will have a big effect on how well or what form the crystals will plate out.

Reading through the forum you will find some much better discussion on silver cells.


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## butcher

From reading the silver cell text that Steve posted, I see the thum cell runs at a suggested 3.0 volts to 4.4 volts and a current of 0.35 to 0.4 amps per square inch of anode area

For discussion lets say 3 volts and 0,35 amps and using one square inch of silver anode area. 
Since Ohms law says: volts divided by amps is equal to resistance.
Then 3 volts divided by 0.35 amps equals 8.57 ohms.
So in this cell the cells resistance is 8.5 Ohms. (Electrolyte and spacing may differ)
Since Ohms law also says: watts = volts x amps.
Then 3 volts x 0.35 amps = 1.05 watts
So the cell is using about one watt (heat work) (again in this perfect cell).

Say I only have a 6-volt power supply (DC battery charger), and want to run my cell on 3 volts.
Two resistors in series, if both are the same size the voltage divides, but the current stays the same through both resistors,
so if I put two resistors, or light bulbs, or silver cells in series the voltage they receive will be half each of the supply, example two silver cells of the above resistance in series on a 6 volt supply battery would get 3 volts each, and if both cell ran at same resistance (unlikely ) the total circuit current would be 0.35 amps, and 2 watts of power used up as heat, problem here the cells resistance is variable, this may work but I want a better way and do not want to maintain two cells,

I could get a resistor from radio shack large ceramic type in a 10 ohm (close to 8.5 ohm of my cell) 10 watts so it can dissipate the heat, and wire it into series with my cell (insert it in to wire going to anode) (plus of voltage supply battery charger to one wire of resistor and jumper from other wire of resistor to my anode silver bar in the cell, now my total circuit will have 18.57 ohms and 0.32 amps, the resistor would get just a little more than three volts my cell just a little less than three volts from my six volt supply, and since the battery charger will actually put out a little more than six volts (about 7.25 volt to charge battery) my cell would be within the 3 to 4.4 volt range,

Ok now but our cells resistance changes and Kadriver said he had read 4 amp draw on his running at 6 volts, this says to me his cell resistance was 1.5 ohms when he done his readings much less than our perfect thum cell here, this is getting close to being a short circuit, (maybe a silver needle fixxin to burn his cloth?), well if our cell shorted out we still have the 10 ohm resistor in circuit, so a most we have is 6V./ 10 ohm = 0.6 amp on resistor, and 0.6amp X 6 volt = 3.6 watts of heat on resistor, our 10 watt resistor can handle that worst case scenario.

But we can use a light bulb instead of a resistor, this will give us an indication of how are cell is running, will limit current from our charger, and divide the voltage from our power supply between the light bulb and the silver cell if we put it in series with the cell as we did the resistor, I would use a 12 volt tail lamp from a vehicle like the #1157 tail light bulb(auto parts or radio shack you can solder wires to it or just get a socket for it) about 2100 milliamp (at 12 volt its hot resistance is about 5.7 ohms, now running cooler on about 3 volts in this circuit that will differ). A shorted cell the lamp will limit current, indicate the short, protect your battery charger.

Again with the light bulb take the positive from your battery charger to one wire of bulb the other wire of bulb to anode silver bar in your cell.
(Different bulbs will give different values their filament resistance varies with type of bulb), you could do experiment with a six volt tail lamp, it would be hard for me to calculate the values as we are running bulbs @different voltages and filaments will heat different, and here your cells resistance is also a variable.

All I can say is Try it you may like it, (and thank OZ for the suggestion).


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## stihl88

Great posts Butcher,

Another option could be to wire in series a Variable Resistor of a high watt value along with an LED and a resettable fuse.
This would be a more sustainable setup with the option to change the voltage with the Variable resistor when or
if required.

I'll be building my own Cell setup over the Christmas break and i might try the setup Ive described here.
I'll be using a PC power supply and can tap into the 3v rail with 18 Amp supply. Now to find a Variable Resistor
than can handle 10 Watt :roll: (May as well leave the trimpot out if using only 3v rail anyway)

I would love to design a dedicated power supply circuit for Cell Refining and make one from scratch, Ive got all the software,
tools and experience but it's probably just as easy to buy a dedicated variable power supply.


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## kadriver

Butcher & Stihl:

Thanks you guys. I am not up on my electrical theory so I had to read what you wrote slowly, but I think I get it.

I have not had a chance to look at the site that Steve suggested yet, but I will.

I like the idea of having a cell rig with a light and circuit protection.

I actually had my cell crystals grow and come in contact with the basket. When I seen it (heard it first) I made a noise I had not heard myself make before.

I did an emergency shut down and thought that I had already ruined my new toy. But the material of that vacuum cleaner bag saved me.

That is why there is silver in the bag in the photo - I changed it out just to be safe - no burn through, and no contaminants got into the electrolyte.

I am really pleased with the performance of that bag material - but i don't know what it is.

I like the idea of having a light bulb as an indicator of short circuit. I assume the bulb would get dimmer as I got closer to a short circuit.

Butcher, thank you for the description of the cat ions and an ions being exchanged. The solution stays the same however. Who thought all this stuff up? My hat is off to them, whoever it was.

Thanks to all.

kadriver


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## Barren Realms 007

Possibly put a dimmer switch in the circuit.


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## shyknee

Shyknee, those crystals in the blue glove are unbelievable - how can I get mine to grow like that?

I used 2 silver cell setups connected in line with a 1.5v @ 300 milliamps plus it took more than 24 hours to grow from a 2" spacing of the anode to cathode ,and i used clean silver for the setup (my electrolyte looked like yours) and saturated the electrolyte with silver first .


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## kadriver

Thanks - am going to try it - those crystals of yours look really dense.


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## stihl88

Barren Realms 007 said:


> Possibly put a dimmer switch in the circuit.



Good idea Barren i forgot about the old dimmers, they can handle the heat!
To try and source a normal trimpot that does the same thing as the dimmer 
you are paying through the nose but a dimmer should be more than fine for
this application. I'll post some pics of my setup when i get around to building it.

*Lazersteve>* If i buy your silver CD can it be downloaded from a host site or do i have to have it mailed to me?


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## lazersteve

stihl88 said:


> *Lazersteve>* If i buy your silver CD can it be downloaded from a host site or do i have to have it mailed to me?



It has to be mailed.

Steve


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## azdave35

i have a silly question that someone might be able to answer: i have a nitric solution that i have cemented all the silver out of...is there any way to cement or drop the copper and lead out of the solution?...i am trying to determine the assay of a silver ore...thanks in advance


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## butcher

when you cemented silver with copper you replaced the silver in solution with copper.
this worked because copper is higher in the electromotice or reactivity series.

you can do this with a metal higher than copper in the series, like Iron.

do some study on metal reactivity series Googling, it will open a new world for you.


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## 4metals

Shyknee,

Those crystals are some of the most dense I've seen, the spindly ones in the beaker look more like what he was generating before tartaric acid. After the tartaric they were chunky like yours but not as large. 

nice work.


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## Oz

Is there a simple way to convert potassium hydrogen tartrate (KC4H5O6) to tartaric acid (C4H6O6)? 

As I am not a chemist, is it necessary to do so in this application? What if anything would the potassium (K) do in a silver/copper nitrate solution? Other typical contaminates?

Sorry for the curve ball.


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## kadriver

I had a problem with the silver cell.

The copper rod used to hang the basket partially dissolved.

Some of this material got in between the basket and the filter and ended up getting into the crystals. There was only a tiny bit, but I am concerned that this contamination has ruined this batch of crystals.

What is this material? Will it burn out when incinerated? Will my silver now be less than 999? Should I disassemble the cell and start over?

If I have to start over, then thats OK. This time I may use a thin pyrex glass rod instead of the copper rod for the cross member support - this will surely eliminate the contamination problem.

Also, the electrolyte is beginnig to turn green/blue. I have included a picture. Silver crystals were still forming.

So far I have gotten about 8 troy ounces of silver from the cell.

Any input would surely be welcomed.

Thanks - kadriver


----------



## lazersteve

I wouldn't worry too much about the copper unless it got in your pure crystals. If it did, then remelt them into a new anode and run it through the cell again. 

You can use any type of rod you like for the support, even a wooden dowel, you'll have to clip the positive lead directly to the hanger hook though if you use a material that is not conductive. I use a large gauge solid copper wire for my rod, but it requires cleaning periodically due to the reaction with the nitrates in the cell.

Steve


----------



## kadriver

Thanks Steve.

What if I treated these contaminated crystals with hydrochloric acid to remove the copper, clean with much boiling water and melt? Could I then presume these crystals are still 999 in purity?

I will then filter the electrolyte, install a new non-reactive support rod and continue to grow crystals.

I think a glass rod support will be the least reactive of any material.

I hooked the lead directly to the hook welded onto the top bar, just like in the silver dvd.

When the time comes, I plan to cement the silver out of the electrolyte instead of going to silver chloride - does anyone see a problem with this?

Thanks - kadriver


----------



## Oz

If you are trying to produce .999+ silver crystal I would keep hydrochloric acid out of the process. You are already casting anodes, just clean out the cell and recast the silver. 

As to cementing your used electrolyte on copper, that is how I handle it. I do everything I can to limit the amount of silver chloride I need to process.


----------



## rbramsey

I am now attempting to refine my silver with a electrolytic cell. I have a couple of questions?

GSP stated that you can run 92.5 silver through the cell but it was harder to do. I can concur. The crystals are very small, and very slow to form. The temperature started at 40 F ( I used 12V to begin with to help raise the temperature of the electrolyte). The results were not good. After letting the cell run for about 30 minutes at 12V ( the electrolyte was warm to the touch, I switched to 6V, and let the cell run for another 2 hours. The current draw was estimated at 2A (needle barely moved on the meter). The volume of crystals was very little. I estimate less than 10ml. Also, there were two distinct colors of crystals. One was bright white (silver) the other was darker with a tint of brown ( copper I presume). I assume this was caused by me running the cell at 12V.

Tonight I adapted a computer PS to run the cell tomorrow. I will use the 3.3V rail. It is rated at 20A. What parameters do I need to watch out for when refining sterling? How the temperature of the electrolyte factor into the cell. How critical is the anode to cathode area ratio? The anode bars I cast are 1-3/8" diameter. The cathode is 1.5 x 2.5. So the ratio is 2.5:1. 

Also, kadiver stated that his crystals didn't dissolve in the electrolyte after leaving them in there over night. Mine dissolved. I guess this means I have too much nitric in the solution. Should there be any free nitric in the electrolyte?

I will setup again tomorrow to run another batch.
Richard


----------



## goldsilverpro

rbramsey said:


> I am now attempting to refine my silver with a electrolytic cell. I have a couple of questions?
> 
> GSP stated that you can run 92.5 silver through the cell but it was harder to do. I can concur. The crystals are very small, and very slow to form. The temperature started at 40 F ( I used 12V to begin with to help raise the temperature of the electrolyte). The results were not good. After letting the cell run for about 30 minutes at 12V ( the electrolyte was warm to the touch, I switched to 6V, and let the cell run for another 2 hours. The current draw was estimated at 2A (needle barely moved on the meter). The volume of crystals was very little. I estimate less than 10ml. Also, there were two distinct colors of crystals. One was bright white (silver) the other was darker with a tint of brown ( copper I presume). I assume this was caused by me running the cell at 12V.
> 
> Tonight I adapted a computer PS to run the cell tomorrow. I will use the 3.3V rail. It is rated at 20A. What parameters do I need to watch out for when refining sterling? How the temperature of the electrolyte factor into the cell. How critical is the anode to cathode area ratio? The anode bars I cast are 1-3/8" diameter. The cathode is 1.5 x 2.5. So the ratio is 2.5:1.
> 
> Also, kadiver stated that his crystals didn't dissolve in the electrolyte after leaving them in there over night. Mine dissolved. I guess this means I have too much nitric in the solution. Should there be any free nitric in the electrolyte?
> 
> I will setup again tomorrow to run another batch.
> Richard



Excess nitric will definitely redissolve crystal and is probably the reason the crystal is forming slowly. As the solution warms, it will dissolve the crystal at a faster rate. To avoid the excess, use a little less nitric than it would take to dissolve all of the silver being used to make up the solution. In other words, there should be a little undissolved silver left over when all the nitric has completely reacted. Theoretically, it takes 1.22 ml of nitric to dissolve 1g of silver and it will take 4.2 ml to dissolve 1g of copper. If you're dissolving sterling to make up the solution, it takes about 1.44ml/gram [(1.22 x .925) + (4.2 x .075)]. In practice, use about 95% of the total nitric you calculate to be required.

When the silver in solution gets too low, it can be increased by adding a known quantity of nitric. This will dissolve about 1g of crystal for each 1.22 ml added.

For your 3.75 sq.in. of cathode area, I would use from .65 to 1.3 amps at 3 to 4 volts. If you go much higher, you will get poor crystal and possibly will deposit some copper.


----------



## elfixx

I have a question for you guys, as you know, the voltage(shown on the rectifier) of a silver cell lower with the electrolyte resistance. I have always ran my cell setting the voltage first to 3v and then let the resistance set, my question is should I keep on running the cell this way or could I set the volatge to 3v once it is running whitout risking contaminating the final product? Perhaps my question isn't nicely formulated, pardon my poor english.

Thank you


----------



## DNIndustry

Been awhile. Thought I would throw My 2 cents in. I'm sure that we all have computer power supplies lying around. I saw on instructables and other places Directions for making your own laboratory power source. 
There are both. 3.3 v & 5 lines. Pending on the units each baby anywhere from 15 up to 50A.
This would give you a much closer setup parameters.


----------



## DNIndustry

I should have read. Already posted.


----------



## metatp

lazersteve said:


> Yes, be sure to maintain a 4" anode to cathode spacing. Also the cathode should be no more than twice the area of the anode



Can you tell me the significance of the cathode to anode area ratio? What happens when the anode is larger than the cathode?

Thanks,
Tom


----------



## kadriver

Hello:

I have been running my silver cell now for a good bit with good results.

The crystals are much easier to work with over cemented silver.

I have cleaned the cell filter bags several times. I usually remove the filter assembly from the cell to another container, then remove undissolved anodes and filter bags (I use double filter bags to ensure no junk gets in my silver).

I wash the slimes into a container, and then treat with dilute nitric acid (50/50 mix of distilled H2O and 70% nitric acid). Then I filter off the residual and add the filtered silver laden liquid to a silver cementing container.

Here is my question: What is this red stuff left over after treating with nitric acid?

I have treated some of the filters that have this red material with aqua regia and got some gold (about .5 grams last time).

I will just continue to save these filters in a plastic bag until I get some info on what this red material is and how to process it.

Thanks to all - kadriver


----------



## goldsilverpro

kadriver,

Looks like a little colloidal gold to me.


----------



## kadriver

Thank you - i will just continue to treat this with AR and get the gold out.

kadriver


----------



## nickvc

I always keep all my filter papers and leave them to dry in a plastic open container and then incinerate them when I have a reasonable amount and recover any pms present. You might find that you have PGMs as well as gold from your silver cell sludges in time especially if your running cemented silver from inquarting,test your AR with stannous before discarding.


----------



## kadriver

I am still new to this business of refining silver.

Somehow I got the impression that I could make up an electrolytic silver cell and then cast anode bars from silver jewelry or sterling flateware and dishes and just throw these bars in the anode basket to refine them.

I found that the cell quickly becomes contaminated with impurities and that weird things start happening in the cell.

For example, I assembled a cell with electrolyte and anodes, but did not connect the electrical leads. I was called away and when I returned about 2 hours later, silver crystals had begun to grow in and around the anode bag and the solution had begun to turn blue!

I was dumbfounded and in my inexperience just decided to hook up the electric leads and go with it.

Big mistake as some i could immediately see some contamination floating around in my electrolyte.

So I disassembled the cell and cleaned everything. Then I put it all back together and got it running fine.

That evening I was leaving the shop so I just turned off the poweer supply to the cell as I have always done.

To my befuddlement, the same problem appeared the next morning - silver crystals had begun to grow in and around the anode bag again.

This time I disassembled the cell and cleaned everthing up before restarting.

I only got about 8 troy ounces from this cell before I took it apart and recovered the silver.

During the last part of operation, a blob of brownish yellow pudding-looking material began to grow on top of one of the crystal formations that had grown to within 2 inches of the anode bag. I have had crystals get this close before, but have never seen this blob form.

As a result of all this, i am now using only cemented silver anode bars in the cell, and i am keeping a close watch to ensure that the crystals do not get too close to the anode basket.

I also remove the anode basket from the cell for overnight storage and reinstall the next morning before startup.

Is it possilbe that there was a weak current going throught the electrolyte even with no power to the cell? 

Any input that would help explain these strange results would be greatly appreciated.

Thank you - kadriver


----------



## lazersteve

It's simply cementation happening from the impurities in your anode. 

Steve


----------



## Goldfinger4

It is quite normal that your electrolyte turns blue, that happens through copper impurities but should not excite you. If your silver concentration is high enough and the current is not too high only silver should crystallize.

When leaving your raw silver in the silver nitrate solution, the copper is dissolved and silver crystallizes on the raw material. 

Ag+ + Cu --> Ag + Cu+

You should inform yourself about electro chemistry: https://secure.wikimedia.org/wikipedia/en/wiki/Electrochemical_series


----------



## kadriver

I removed the battery charger and replaced it with a PC power supply using the 3.3 volt rail. The crystals are nice and beefy and the cell is working perfectly.

I will do some study on electroysis to get familiar with the processes in the cell.

The silver did not look like cemented silver that I am used to seeing. The silver that was forming on the filter bag looked exactly like the silver crystals growing on the cell.

I will just make a practice of removing the anode bag when the cell is not in operation.

Thanks for all your input - kadriver


----------



## ORCB

Hi all,

I see there's discussion of lasersteve's DVD on this thread, so I hope this is the right place to ask some more technical questions about it. I just got the DVD, good vid. 

I'm wondering why the copper ions from the sterling are not reduced at the cathode, so why are only the silver ions reduced? Also, what's the function of the basket, is that somehow selectively trapping the base metals from going into solution? Yet, I know some copper ions get into the solution, if there's copper in your silver, cause in the video, eventually the electrolyte will go blue. 

Thanks!


----------



## ORCB

ORCB said:


> Hi all,
> 
> I see there's discussion of lasersteve's DVD on this thread, so I hope this is the right place to ask some more technical questions about it. I just got the DVD, good vid.
> 
> I'm wondering why the copper ions from the sterling are not reduced at the cathode, so why are only the silver ions reduced? Also, what's the function of the basket, is that somehow selectively trapping the base metals from going into solution? Yet, I know some copper ions get into the solution, if there's copper in your silver, cause in the video, eventually the electrolyte will go blue.
> 
> Thanks!



Sorry to double post. Is it cause the electrolyte is saturated? Even still, I don't see how that would select the oxidized silver ions to replace the reducing ions in the solution over copper ions. Hmmm. Looking forward to answer.


----------



## lazersteve

In the video I start off with cemented silver (98%+ purity) so there I very little copper present. As the electrolyte builds up copper you have to change the electrolyte to prevent the copper from co-depositing.

Keeping the volts around 3 to 4V will also keep the copper out of the crystals.

Lastly, copper tends to want to remain in the solution more so than the silver (think cementation reaction) . The silver is more reactive, therefore it's the first to deposit at the low voltage.

Maybe some of the other members will post their theories why the copper doesn't co-deposit?

The basket is there to catch the insoluble slimes that are in the silver. These slimes are gold and other metals that are not readily soluble in nitric acid. Without the basket you end up with black specks of gold and other metals in your clean silver crystals.

Steve


----------



## metatp

I just tried a new cathode I created made of stainless steel. I tested it first in nitric acid for hours to make sure it didn't start to dissolve. The "arm" of the cathode going up the side of the beaker is about a half inch wide sheet of the same stainless sheet. I coated it with plastic that was a dip coating used for applications like coating pliers handles. This is what happened:

Before I started the cell, I dissolve 100g of cemented silver powder in only enough nitric acid to dissolve the silver (150ml of distilled water).

I used heat to assist in dissolving the silver (I may have left it on the heat a bit too long and the solution was at a slight boil enough after the silver was dissolved.

I let the solution cool and added enough distilled water to fill the cell.

All seemed fine with the solution have a slight blue tint.

When I started the power at 3V and about 1Amp, silver started growing right away and faster than I am used to seeing. They grew like grass more than crystals. It was darker than the normal crystals. This was weird, but it got weirder. silver started plating on the coated "arm" and crystal started growing from there as well. I even a a small area on the glass beaker than looked plated.

Any speculation to why the crystal grow was this way? Cemented silver should have been incinerated? Coating on "arm" not thick enough? Could the silver nitrate be supersaturated since it was boiling for some time after the nitric acid was used up? It is a little perplexing. 

Also, the anodes are cemented silver that was melted into ingots.

I am starting over with my graphite cathode for now.

Thanks,
Tom


----------



## Barren Realms 007

I'v seen that coating be porus. This would allow your crystals to grow thru it.


----------



## 4metals

I've had excellent results using a PVC tape to wrap the cathode connection down to the plate. McMaster Carr sells it.


----------



## metatp

Barren Realms 007 said:


> I'v seen that coating be porus. This would allow your crystals to grow thru it.


They don't appear to be growing through, but growing up the side. I can peel it off and it started from the bottom.


----------



## Barren Realms 007

HTPatch said:


> Barren Realms 007 said:
> 
> 
> 
> I'v seen that coating be porus. This would allow your crystals to grow thru it.
> 
> 
> 
> They don't appear to be growing through, but growing up the side. I can peel it off and it started from the bottom.
Click to expand...


Now that's wild. 8)


----------



## metatp

HTPatch said:


> lazersteve said:
> 
> 
> 
> Yes, be sure to maintain a 4" anode to cathode spacing. Also the cathode should be no more than twice the area of the anode
> 
> 
> 
> 
> Can you tell me the significance of the cathode to anode area ratio? What happens when the anode is larger than the cathode?
> 
> Thanks,
> Tom
Click to expand...

I never received an answer to this question, so I tried it out. It appears that with an anode being larger than the cathode leads to growing silver wool like balls (marble size). I did not get the branch like crystals unless I reduced the gap between the anode and cathode or increased the voltage. The crystals appear to be pure, but may require more rinsing. Has anyone else seen this same results? When I reduced the anode size, I got the typical crystals. Does anyone think that we can make denser crystals as we reduce the anode size?

Thanks,
Tom


----------



## lazersteve

Current flow through the cell is a function of the cell resistance which is function of the electrolyte, cell spacing, and the ratio of the areas of the anode and cathode.

Steve


----------



## Westerngs

Small amounts of tartaric (1g/l) will help make more dense crystal. However, don't overdo it on the tartaric as it will cause anode slimes to migrate out of the filter bag and deposit on the crystal.

It is really not necessary to use tartaric if you keep the Ag concentration of the electrolyte >60 g/l.

Also, if you add CU(NO3)2 to the electrolyte to about 30 g/l, it will help the conductivity and help the Ag plating. If you keep the voltage to under 3 volts you should not co-plate much Cu and your Ag should still be at least 0.9999 pure


----------



## goldsilverpro

Good to see someone agree with the addition of some copper. I also started with about 30g/l copper. I was running 12, 30 gal Thum cells.


----------



## rusty

4metals said:


> I've had excellent results using a PVC tape to wrap the cathode connection down to the plate. McMaster Carr sells it.



Shrink tube available at your local automotive parts store. Comes in pre-cut lengths or rolls.

[youtube]http://www.youtube.com/watch?v=hnWhXVFSN7g[/youtube]


----------



## BrewCity

I could use a bit of assistance with my first silver cell. 

I've recovered silver from approximately 1855g of Sterling (a few small .8 pieces in the lot). Cementation and silver shot creation appears to be right on schedule. I created quite a bit of electrolyte and made a silver cell as seen in kadriver's YouTube videos (outstanding work, Sir). I'm still working to perfect my bar pouring skills, so for now I'm just using a silver round as my anode shoved into the cemented silver shot (anode basket). My stainless steel bowl holds 2.5L and currently has a silver density of 166 g/L. 

The problem is my power supply is running at 3A at about only 2V. If I increase the current, I can reach 3V, but I'm afraid the current would be unexceptably high (and create impure silver perhaps). I understand it should be only about 1A @ 3V. I tried increasing the electrolyte silver density 150g/L to 166 g/L, but it didn't appear to have much effect. Can anyone point me in the right direction to get my silver cell on track?

I appreciate any guidance you all can offer me.


----------



## Palladium

If you just started the cell it will need about 24 hours to acclimate. Push your voltage up to about 4.1 volts and as the cell levels out the volts will drop.


----------



## BrewCity

Thank you! 

Okay, so I have changed out my 3A fuse to a 10A fuse. I drove the power supply up as far as it would go under the present conditions. I am now running 5.02A at 2.4V (I'm giving her all she's got, Captain). After only 10 minutes, I have white, crystalline silver formation along the scratches of the stainless steel bowl. I will continue to monitor closely to see if/how much the amperage and voltage change over time (adjusting voltage upwards as this setup permits). 

Can I just point out how difficult it was to find truely stainless steel bowl? Goodwill, Target, Walmart - all magnetic. I ended up just permanently borrowing our kitchen bowl from 10-15 years ago. I replaced it with one of the magnetic bowls I found in the store. It's a shame that a stainless steel stamp doesn't really mean much anymore.


----------



## Palladium

If the max is 5 amps and your only pulling 2.4 volts then you're in good shape. Amps is what produces the silver, not the volts. Higher voltage leads to co precipitation, but will not produce more silver unless the amps are able to rise with it. You're pegged out now so a higher voltage will do no good.


----------



## FrugalRefiner

BrewCity said:


> Can I just point out how difficult it was to find truely stainless steel bowl? Goodwill, Target, Walmart - all magnetic. I ended up just permanently borrowing our kitchen bowl from 10-15 years ago. I replaced it with one of the magnetic bowls I found in the store. It's a shame that a stainless steel stamp doesn't really mean much anymore.


There are many varieties of stainless steel. Some are always magnetic. Most stainless steel, even the 300 types, becomes magnetic when it is worked, as sheet stainless is during the bowl making process. They were probably all some variety of stainless.

Dave


----------



## BrewCity

Palladium, thank you again for the clarification on Voltage vs. Amperage for silver crystal formation. Everything is progressing quite well, I believe. My now warm (but not hot) silver cell is continuing to hold steady at 5A and 2.4V. The crystals are forming at a pretty good pace and continue to appear very white/brilliant silver.

UPDATE (7 hours): My cell is still operating at 5A, but the voltage has fallen to 1V. The rate of silver growth is still excellent. I haven't setup lights in the shed (or perhaps lab now) yet, so a picture will have to wait until the morning.

UPDATE (17 hours): My voltage dropped to 0.7V while maintaining 5A. I turned off the power supply, opened up the cell and found a crystal had risen from the bottom of the bowl and into the anode basket. It's unclear if it was fully contacting the anode bag. I knocked down the tall crystal(s) at the bottom of the bowl and the anode basket. Everything was closed back up and power restored. My cell is back to 2.4V at 5A. I will be working on adding a plastic ring to raise the anode bag higher as the distance to the bottom is closer than the sides of the bowl. Crystal growth clearly slowed overall, but they are still clean and the electrolyte is beginning to show signs of copper presence.

UPDATE (22 Hours): Voltage dropped to 1.7V at 5A. Inspection after powering down revealed a new, tall silver crystal which had formed below my anode basket. I again knocked it down with my glass rod. I made and added a plastic ring to raise my anode basket by ~0.5 inches, increasing the short distance to the bottom of my bowl. This process also effectively reducing my (exposed) anode size. I added a small amount of water (my silver concentration was greater than necessary anyhow) to raise the electrolyte level back to the starting level. This was the amount lost by reducing the displacement of the now shallower anode. After reassembling my cell, the voltage has now been increased to 3.0V at 5A.

UPDATE (26 Hours): Voltage dropped to 2.8V at 5A. More uniform growth noticeable but a few tall crystals were knocked down preemptively. Post-tree-felling, after turning the cell back on, the voltage popped up to 3V, but fell within 10 minutes was back to 2.8V. The crystals all over the bowl are forming faster than I had anticipated, which will require more frequent monitoring than I realized (minimum 8-10 hour inspection intervals, but more if possible).

UPDATE (41 Hours): Voltage dropped to 2.5V overnight. Crystals grew up into and formed within the anode basket. Powered down the cell and knocked down the tall crystals as well as intermediate crystals from the bottom of the bowl (probably still the closest point to the anode). All knock-downs were moved to the "corner" of the bowl, or rather the furthest point from the anode. This buildup of materials should make a better-shaped hemisphere, allowing for more uniform crystal growth. Reassembled and powered up the cell. The voltage is now 3.5V @ 5A.


----------



## goldsilverpro

BrewCity said:


> I could use a bit of assistance with my first silver cell.
> 
> I've recovered silver from approximately 1855g of Sterling (a few small .8 pieces in the lot). Cementation and silver shot creation appears to be right on schedule. I created quite a bit of electrolyte and made a silver cell as seen in kadriver's YouTube videos (outstanding work, Sir). I'm still working to perfect my bar pouring skills, so for now I'm just using a silver round as my anode shoved into the cemented silver shot (anode basket). My stainless steel bowl holds 2.5L and currently has a silver density of 166 g/L.
> 
> The problem is my power supply is running at 3A at about only 2V. If I increase the current, I can reach 3V, but I'm afraid the current would be unexceptably high (and create impure silver perhaps). I understand it should be only about 1A @ 3V. I tried increasing the electrolyte silver density 150g/L to 166 g/L, but it didn't appear to have much effect. Can anyone point me in the right direction to get my silver cell on track?
> 
> I appreciate any guidance you all can offer me.


I ran my large 30+ gal silver cells at about 240A or, 8A/gal, with no severe overheating. In sunny L.A., I don't think the solution ever got over 110F-115F, which is OK. Your cell is .66 gal and I think you could run 5 or, maybe, 6A without overheating. The voltage ran between 3 and 4 volts.

*HOWEVER:*
The amps required are also related mainly to the anode current density (CD). This is the number of amps per square (inch; foot; cm; dm; m; etc.) of electrode surface area. Per square foot is the handiest for me. In a real production sized silver cell the anode and the effective cathode areas are about the same and, in every book I've read, the anode CD should be somewhere between 25 to 50A/ft2 (for a Thum cell, at least). In my cell, at 240A, and 6ft2 of anode bars, I ran about 40A/ft2. The effective cathode CD was in the same ball park.

At the cathode, you are mainly interested in the characteristics of the crystal deposited. The consensus in the literature is that the crystal should be short and dense, mainly for rinsing purposes and being able to pack more crystal in a crucible.

At the anode, you want to dissolve the bars efficiently. At 100% anode efficiency and 1 amp, you would dissolve 4.025g of pure silver in 1 hour. Don't ever expect 100% efficiency.

The silver cell will work (dissolve anodes and plate out crystal) under almost any conditions: hi/lo Ag, hi/lo Cu, hi/lo A, hi/lo V, hi/lo temperature, etc. However, if you want to dissolve the anodes efficiently and get the most desirable crystal, which is pure, you must operate within the proven ranges. You usually have a little slack, though.

You need to estimate the surface area of the bottom of the silver in the basket. For each square inch, you should be in the range of .17 to .35 amps. At that amperage you will pull 3-4V at an anode/cathode distance of 4.5". If the anode/cathode distance is less, the voltage will be less for the same amperage. The amps are the important thing!


----------



## Sputins

Dear GRF, 

I’ve greatly enjoyed learning about refining Au and Ag from the advice and information provided on this forum. Professionals are found here indeed.
I’ve been successful at creating fairly clean sliver cement, melting it and forming into nice shiny Ag metal shot. I will soon have enough Ag shot to consider having a go at using a silver electrolytic cell. I have built one very similar to the one kadriver (and others) have built and shown. (Nice work btw). However I may have a go with a beaker with a smaller volume to first to test out my anode basket filter material.

So my question is: What are suitable filter materials for this basket. I am having problems finding some Dacron type material as kadriver used. What else would work? (Obviously resistant to HNO3). 

I have found some pillow protector material made of Polypropylene fabric. Sound okay? 

Any other ideas for suitable filter material?

I’m looking forward to creating my own lovely looking pure silver crystals.

Sputins.


----------



## Lou

Just get unbleached fine muslin cloth


----------



## Research135

Vacuum cleaner bags are cheap.

BTW and probably not so off-topic: An state-of-the-art thinking and process for all precious metals seems to be converging in: Do all the valuable metals within 24 hours via chemical methods, and process the wastes (copper, etc) electrolytically over days or whatever.

In other words: Silver and gold cells are relics. Old technology. Like black and white TVs. Don't waste your time.


----------



## Palladium

Silver and gold cells are still very much alive in the precious metals industry. They are nowhere near relics. That's like saying the internal combustion engine is a relic because of electric cars.


----------



## Sputins

Thanks for the replies. I can try the muslin cloth and the polypropylene material while I continue to look for a suitable vacuum cleaner bag. (At local stores they're all paper, or no longer hold much stock because of bag-less vacs). 

I don’t quite understand the Au / Ag cells are relic old technology comment, without saying why and what replaces it. For me the silver cell is a do-able now process. As you might gather I’m a new comer to refining processes (and to the GR Forum), although I do have over 20 years of experience working in an analytical minerals laboratory. 

Picture below shows some feed stock (from cemented silver) for the cell and to prove I’ve actually done something practical. The long slender bar is 1 troy Oz.


----------



## Palladium

Had that statement been clarified to the processing of ultra pure elements I might have agreed with it, but electrolysis is used industry wide even today as a cheap effective way to separate metals. Both have their place, but to say it is a relic is far from the truth.


----------



## Research135

Palladium said:


> Had that statement been clarified to the processing of ultra pure elements I might have agreed with it, but electrolysis is used industry wide even today as a cheap effective way to separate metals. Both have their place, but to say it is a relic is far from the truth.


You heard it here first!. hehe.


----------



## Sputins

I’ve had my first go at the beaker sized 300ml silver cell, with 149mls of water, 149mls of Nitric Acid and 124.4g of silver (from cemented silver). 
So there was a little copper in my silver as seen from the solution colour. Not too much though.
I adapted a PC power supply 3.3volts at 10amp max, with a 4 amp in-line fuse. 
I tried using two layers of the Polypropylene pillow case protector material ($3 each) and it seems to work just fine. 

Let the pictures speak! 




Growing…





Just before the fuse blew due to short circuit...





Next batch… 





My first ever batch of glorious gleaming silver crystals! Only about 80 grams here. 

I’ll keep making crystals until I have enough for the bigger silver cell of about 3Ltr capacity. 
Thanks for all the advice and info found here on the GRF.


----------



## Palladium

Looking good!


----------



## Sputins

Palladium said:


> Looking good!



Thanks! 

As seen I’ve copied the other silver cell designs seen here on the forum:

Below: my new electrolytic silver cell, the stainless steel bowl contains 600g of silver made up to 4 Liters. (150g/L) It’s all housed in a fume cupboard. 




Below: With the cover off showing the silver crystals forming in the stainless steel bowl, this bowl seems great, the surface is so polished that the crystals forming around the brim get too heaver and simply slide off. This is after around 24 hours of running the cell, it consumed all of the silver shot in the anode bag, so I’ll have to add more silver shot. (It consumes it faster than I can produce the shot). 




Below: Close up of the crystals in the bowl. These are not as dense as with the beaker because the electrolyte is less concentrated than with the saturated solution with the beaker. As you guys would know, the camera fails to pick up the full shininess of these crystals. To the eye these look spectacular!




Below: Anode basket and filter. The filter material used is polypropylene pillow case protector material. Probably the basket is too big, I might make a smaller one to fit inside it.


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## Sputins

On a micro-scale this is exactly what's happening: 
https://www.youtube.com/watch?v=fnyBldC4Ra4[youtube][/youtube]

Yeah, its cool photography!


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## saadat68

Hi
From reading the silver cell text that Steve posted, I see: 
Electrolyte 12 to 12.5 grams of silver nitrate per 100 mL of distilled water or
75 to 100 grams per liter of silver

So if I have 1 liter electrolyte I must have maximum 100 gram silver in it. But it contains silver in the basket too ?
In other words I must have for example 50 gram silver in electrolyte and 50 gram in anode basket?

Thanks


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## 4metals

Saadat,

The concentration of silver in the electrolyte is kept as constant as possible, the weight of silver in the anode basket will constantly be digested and pure silver will deposit at the cathode. When the instructions speak of a concentration of silver in grams per liter that is the concentration in the electrolyte solution. The weight of silver in the basket doesn't matter, you need surface area of anodes to dissolve so you keep adding as the anode basket silver goes down. The trick is to analyze the bath for silver because if you are processing sterling silver the copper will climb and the amount of silver in solution tends to drop.


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## saadat68

Thank you!
But I'm sorry I don't understand exactly because of my English
You say if we keep adding silver in anode constantly ( for example cementd silver ) and with this way we keep electrolyte concentration constant 
Is that right?


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## 4metals

Basically it is right but the cement silver needs to be melted into anodes, you cannot use powdered cement silver. 

The silver will drop in concentration as the copper increases. For a small use it for a single lot of silver sized cell (like the ones described here with a stainless pot for the cathode) you usually run out of silver before the copper gets too high. But after copper gets above 60-70 grams per liter it starts to plate out with the silver. 

So if you are going to produce a lot of silver in a production cell, you need to learn to titrate the silver concentration to control the cell. 

Buy and read Goldsilverpro's book, it is worth it he has an entire section on silver cells and the titration. 

GoldSilverPro's eBook For Sale.http://goldrefiningforum.com/phpBB3/viewtopic.php?f=84&t=22327&p=233617#p233617


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## saadat68

Hi
Thanks 
I know how I must titrate silver in electrolyte. Yesterday I read a topic about it that fined from your library (mini cell)

I will buy that book in future 
Thanks


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## saadat68

Hi
From reading the silver cell text that Steve posted, I see: 

*9. pH 2-6 HNO3
*
What is it's mean ?
Is it electrolyte PH range ?

Thanks


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