Hands Free Silver Chloride Conversion

There is only one thing I hate worse than having to wait overnight for gold to settle completely and that is having to manually stir silver chloride while adding sodium hydroxide (lye) to convert the AgCl to silver oxide for the lye and sugar silver chloride conversion to elemental silver metal.

I made a stirring bar out of 3/8 PVC pipe about 2.5 feet long. I used a nylon bolt from Lowes and three gas powered model airplane propellers, with the ends trimmed to shorten them a bit. I used the nylon bolt with threads that created an interference fit inside the ID of one end of the 3/8 PVC. I glued the propellers and the bolt liberally with "liquid nails" also from Lowes - Ace Hardware has it too.

I allowed the liquid nails to cure for several days before I began using the stir bar. I have used it for many batches of silver chloride - 2 liters of AgCl in a 4 liter beaker is about the max capacity, but a large beaker would allow more capacity. Or a person could just do it in the 5 gallon bucket with no beaker.

It only takes 5 minutes to set it up and less to take it apart. The big advantage is that I can let it run while performing other tasks in my shop - completely hands free.

I made some photos of the apparatus.

I use a small wireless hand drill set on high speed. It is clamped in a ring stand. A one gallon jug of tap water acts as a counter weight. A three inch steel hose clamp is fashioned to hold the trigger of the drill. It can be tightened or loosened with a screwdriver to control the speed of the drill/stir bar.

The 5 gallon bucket lid has a small hole cut into the center, the the 3/8 PVC stir bar fits into this hole and acts as a bearing to steady the stir bar as it operates. A larger hole is cut to allow addition of water and chemicals.

I can shine a flashlight into the large hole and observe the silver chloride as it converts. It is easy to tell when all of it has converted because the solids turn completely black with no traces of white silver chloride at all. I add the lye in small doses then let it stir while doing other things in my shop. A little while later I check the color. If there is still white I add a little more lye and repeat this until all the chloride has converted - it makes this task easy to do, almost enjoyable!

Pretty cool set-up! Looks like you've been taking lessons from No Idea! :lol:

Great setup!

I was going to throw away a couple of drills with broken batteries that I got with some scrap. Now I'm going to keep them. It's easy to add a cable directly to the motor and drive it from the variable power supply for my silver cell.
I can see the same setup for leaching ashes or other powdery materials.

Göran