Silver Electrolytic Cell Volume

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kadriver

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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
 
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
 
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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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
 
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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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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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
 
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
 
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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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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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.
 
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
 
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
 
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
 
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.
 
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
 
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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