Stainless Steel Silver Cell

[Drimacus]

nickvc, may I ask what sort of anode filter paper you use in your stainless steel silver cell, and whether more than one layer is used?

 

[kadriver]

The whole purpose for me was the other values, the slimes very aptly named, and the quality of the silver secondary but some of the crystal produced has been beautiful and I'm trying to keep it at 999 for pure aesthetic reasons at present, maybe I'll find an out for the product at a later stage.

The silver is a by-product of what you are really after? Wow, now that is what I call refining.

Makes my puny output seem almost a waste compared to what you've got going Nick.

I was talking with another member who is experimenting with the idea of using sterling anode bars, like you are doing.

I will direct him to this writing, he should find it very interesting.

I tried using sterling/925 anode bars and I only remember the cell becoming fouled very quickly - but I did not keep working at it, just resolved to making anodes out of cemented silver with the purity of those bars up around 99%.

Here is a fact that I may have completely overlooked;

The silver in the electrolyte is depleted as the cell operates, the copper goes into solution as the silver gets plated out, with the dissolving anode bars replenishing the silver, but at a rate that can not keep up with the silver being depleted - is this statement true?

If it is, then I have completely missed the ball with respect to silver depletion in the cell.

I thought the silver concentration stayed the same as the anode bars dissolved and replanted at the cathode, with the electrolyte acting as the "transfer media" only.

Now things are making a bit more sense to me - the nitric additions (to dissolve some more silver into the electrolyte), accounting for the increase of copper concentration as the cell operates.

I have been running a silver cell for at least a year now. It amazes me how some important information can just fly right over my head.

kadriver

 

[philddreamer]

Nickvc wrote:

The colander works really well and like Phil mentioned I see larger growth near the connection to the bowl so I'll try the double connection.

I would like to point out, that GSP said that when splitting the connectors, the length and clips should be as identical as possible so the current flow is as even. If one wire is shorter than the other, more crystals will deposit at that point.
Phil

Kad wrote:

The silver is a by-product of what you are really after? Wow, now that is what I call refining.

I'm kinda doing the same but with copper, going after the copper and having the gold and PGM's as by product. I belive Palladium is doing the same.

 

[kadriver]

Converting the cell has opened a whole new set of learning curves for me.

Here is the cell interior after running all night.


I also increased the volts to 3.4V and the amps climbed to 1.3A and added some jumper wires to distribute the electrical contact around the bowl more evenly.
I tried to get a better "angle of attack" with the clips, but it kept slipping off the edge of the bowl, so I had to leave it connected as pictured.


I am dissolving another 200 grams of silver crystal to add to the cell to get the silver concentration higher.


kadriver

 

[sena]

Good work kadriver !, could you use some thing transparent (acrylic sheet) so that you could watch silver not lifting the plastic tray.

Thanks
Sena

 

[nickvc]

nickvc, may I ask what sort of anode filter paper you use in your stainless steel silver cell, and whether more than one layer is used?

I'm not using filter papers but a sheet of polypropylene filter material that my chemical supplier gets me, for free... I'd use the muslin that GSP suggests, if its good enough for him need I say more!

 

[nickvc]

Kevin I'm no chemist but the way I viewed it was that copper needs more nitric to hold it in solution than silver does so as the copper builds up the silver slowly depletes so I just add more nitric again just by gut instinct or fresh electrolyte and remove some of the old one. I'm sure there's a scientific way of doing this but as I said I'm no chemist :shock:

 

[kadriver]

Got it Nick. I'll be measuring the copper in solution using a spectrophotometer in the near future - take some of the guess work out of it.

I added some fresh electrolyte to the cell, 205 grams of pure silver dissolved in dilutre nitric acid.

After adding this dose of fresh silver nitrate, the amps climbed to 1.8 amps (plus i adjusted the volts up to 3.6v DC).

kadriver

 

[Palladium]

Here's the guy i get all my stainless from. He has some good deals from time to time.
http://www.ebay.com/sch/513fitworks/m.html?_nkw=&_armrs=1&_from=&_ipg=25&_trksid=p3984.m1439.l2654

 

[mikeinkaty]

Palladium -

Is there an advantage to using a round bottom bowl instead of a flat bottom SS bucket? I have a 1 gallon bucket bought from WalMart for $11. I was thinking of grinding a SS spatula to the same diameter as the bucket to facilitate cleanout. But, I, and my granddaughters, still like to watch the crystals grow so I may keep using my glass containers for a while yet.

Also, with my open top glass container I have been losing H2o from the solution by evaporation. It just dawned on me that that probably was tending to keep the Ag concentration more constant. I have just been adding water to keep the tank full. In the future I think I will keep AgNo3 solution at hand and just add more of that to keep the cell at the same level. Am I correct in thinking that one whould have to process about 800 ozs of 990 silver before the copper concentration reached the cutoff of about 9 oz/gal?

Mike

 

[mikeinkaty]

nickvc, may I ask what sort of anode filter paper you use in your stainless steel silver cell, and whether more than one layer is used?

I'm not using filter papers but a sheet of polypropylene filter material that my chemical supplier gets me, for free... I'd use the muslin that GSP suggests, if its good enough for him need I say more!

I must have bought to coarse of muslin cause I was getting leakage of slime through the pores. I switched to coffee filters and get no leakage at all now. I wrap the bar with the filter and secure it with a short zip tie. On one 8 ozt bar I used 2 filters and that worked fine too.

Mike

 

[Palladium]

Are you sure it's REAL stainless and non magnetic?

 

[mikeinkaty]

Are you sure it's REAL stainless and non magnetic?

It is slightly magnetic to my large magnet that I robbed from a old disk drive. That magnet is so strong that I can hardly pull it off from a cast iron block. The cathode in my cell has the same characteristic and the electrolyte has not fazed it one bit.

Edit - no, the bucket is not magnetic. The serving tray that I got at Goodwill that was used for the cathodes in both my cells is slightly magntic.

Mike

 

[kadriver]

Good work kadriver !, could you use some thing transparent (acrylic sheet) so that you could watch silver not lifting the plastic tray.

Thanks
Sena

I am looking for a larger anode basket and a see-thru cover as you suggested.

Plexiglass might work, put it may become cloudy over time from the exposure to cell operation.

kadriver

 

[Smack]

Poly Carbonate is more durable and also more expensive. Any glass shop would have it or could order it.

 

[mikeinkaty]

Good work kadriver !, could you use some thing transparent (acrylic sheet) so that you could watch silver not lifting the plastic tray.

Thanks
Sena

I am looking for a larger anode basket and a see-thru cover as you suggested.

Plexiglass might work, put it may become cloudy over time from the exposure to cell operation.

kadriver

It just occurred to me that if you use a cover larger than the opening then you could move the position of the anode if crystals started getting to close to it. I have not been using a cover but may start to reduce evaporation. I have been moving the anode around as needed and adjusting the current to keep it constant if moving the anode makes it change. If alligator clips around the rim of the cell interfere with the cover then you could always drill holes just under the rim and put in SS screws to connect to. Thin neoprene washers could be used under the head of the screw to make them water tight. Neoprene is highly chemical resistant.
Mike

 

[kadriver]

Neoprene - I'll make sure and use them when I install the stainless threaded lugs after I shut the cell down.

I am going to eliminate the clips completely (except the clip on the top that goes to the anodes in the basket).

Someone had a good idea to install the cathode connection on the bottom of the bowl, I may experiment with this idea.

Kadriver

 

[Smack]

You could take your bowl to a welding shop and have them Tig a sst bolt to the bottom, then sit the bowl over a hole with the bolt facing down through the hole then make your connection.

 

[mikeinkaty]

Neoprene - I'll make sure and use them when I install the stainless threaded lugs after I shut the cell down.

I am going to eliminate the clips completely (except the clip on the top that goes to the anodes in the basket).

Someone had a good idea to install the cathode connection on the bottom of the bowl, I may experiment with this idea.

Kadriver

I would just set the SS pan on a metal plate and run a wire to the plate. Have to remember to clean it occasionally. But, would horizontal vs vertical make a difference? I've wondered why some people refer to some of these cells as 'horizontal cells'. I've also wondered if lining the top inside of a SS container with saran wrap (or something similar) would keep crystals from growing at the very top of the solution. Would that be a bad thing to have crystals growing at the top??

Mike

 

[amesametrita]

the worst cell design i've ever seen