----- Original Message ----- From: "Joseph McAllister"
Subject: Re: Used fixer?
Doesn't the steel have to have a current applied to it to attract the silver deposits? When I was working in a lab that used a lot of fixer, we had rotating stainless steel drums in wooden tubs with a voltage applied. Don't know the details, but we shipped over 350 pounds of silver a month that we had to break off the drums with hard rubber no- bouce hammers.
Thats the old school way. Applying DC current to crack the silver out of solution. I used machines like that back in the 80s as well. The way it's done now is with steel (more likely iron) wool in a tank and uses a simple catalytic reaction similar to what happens in a water softener. The silver bearing solution is pumped through the recovery tanks (I've even used gravity feed systems for this) and the iron is sacrificed to recover the silver. Over time it makes a hell of a mess of the drains, and I realy don't know if the iron heavy tailings are any more environmentally friendly than saturated fixer.
William Robb
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