My 'hobby shop' silver electrolsys cell

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mikeinkaty

Well-known member
Joined
Nov 30, 2012
Messages
408
The cells I put together (2) worked well for my needs. I could run 8 ozs through them before having to do a clean out. I had 2 Variacs with fan cooled full wave rectification capable of up to 120 volts and 20 amps. However, 3-6 amps and 3-6 volts are all that's needed for this sized cell. A 12V battery charger would work if set at the 6V setting and by putting some resistance in series with it and the cell to limit the current as desired. I had an ampmeter and voltmeter that I used to monitor the cells. At first I used 6 amps but soon changed to 3 amps to get the larger sized crystals. I did not care for the thin wispy crystals even though they were beautiful! At 3 amps and with 8 ozs in the cell it would take about 12-15 hours to finish. I kept the amperage steady and let the voltage go where it may. This produced larger crystals that were easier to work with. Oh yeah, I expect one could do about 80 ounces in this size cell before the electrolyte would need to be changed. Mine were still going fine after about 70 ounces each. This could be less though if higher currents are used.

The jars were purchased at Wal-Mart for $7, each. I used about 3.5 liter of silver nitrate solution in each and would add distilled water occasionally to make up for evaporation. The electrolyte was 8 ozs of 98-99% silver disolved in nitric acid, filtered, and diluted with distilled water to 3.5 liters. Make sure all the nitric acid is used up by the disolve. Throw in more pieces of silver until all reaction has stopped. Follow the rules here in this forum for determining how much water to use and how much acid to start with.

The cathodes were pieces of a thin SS serving tray found at a Goodwill store for $1. The connection was a piece of the same tray, 1/2" wide, and insulated with heat shrink tubing obtained from Radio Shack. They were bradded to the cathode using a short SS screw. The connection was good and never had problems with it. The cathodes were about 3" wide and 7" long and bent to conform to the inside of the jar. Keep the cathode at the bottom of the jar. With the anode at the top of the solution and using low amperage you shouldn't have any problem with crystals growing up and into the bag.

The anodes of course were my 980-990 silver bars. The connection was achieved by drilling a 1/8" hole about 3/8" deep in the bar and 'hammering' in a piece of aluminum wire (heavy hammer and an anvil). I got a 1' piece of aluminum entrance cable at Home Depot. After the wire was in place I would put a 1" piece of heat shrink tubing around the wire down where it connected to the silver bar. The silver bar was then wrapped with a coffee filter which was affixed with a small plastic zip tie around the aluminum wire. The anode was suspended in the cell so the top of the bar was just below the surface. Most of the time the entire bar would be dissolved and the cell current would go to zero. Other times a small stub stub of silver would drop off the amuminum wire stopping the current.

Clean out was done with a large slotted spoon. I used a small SS bowl (goodwill, $1) to collect the crystals and a hotplate for drying.

Hopes this helps someone!

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Learned alot since posting this thread. That voltage shown on the meter on the right is to high. That might cause base metals to plate out. I now try to get the max current I can without going over 1.5 volts. At 3 amps, or lower, I get better crystals to work with. Sometimes I can get 3 amps at 1 volt.

Mike
 
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