I found a post recently that informed me of a $35 silver recovery unit from Porter's Camera. I bought one, and it works great--now I just pour the remaining liquid down the drain. I have heard in the past that you can put your selenium toner into silver recovery units. Does anyone know anything about that? Will it make the toner safer to dispose of?

-- Ed Buffaloe (edbuffaloe@unblinkingeye.com), February 07, 2000

Answers

I have to do some more research, but I would think that the selenium is mostly gone when the toner stops working. Does the selenium replace some of the silver to give the toning/protection? If so, the spent toner is already low on selenium, but may be high on silver.

-- Terry Carraway (TCarraway@compuserve.com), February 08, 2000.

Terry generally knows more chemistry than I do, but I think that exhausted toner means there is practically no selenium left, and I also think that the toner works by depositing selenium on the silver, rather than replacing it.

If this is correct, then you won't get any silver from the used toner, nor will you make it any safer.

-- Alan Gibson (Alan@snibgo.com), February 08, 2000.

Alan,

At least we agree that the selenium is mostly gone when the toner is exhausted.

In that case, it wouldn't hurt to toss the toner into the silver recovery process, it might not just do anything.

-- Terry Carraway (TCarraway@compuserve.com), February 09, 2000.

Terry, I phrased my reply badly, I didn't mean that I disagreed, rather that I would bow to your superior knowledge.

Yes, I suspect Ed won't recover any silver or selenium, but I can't see that it would do any harm. Well, unless the toner is still active, and puts selenium in the mix, which the silver recovery people might object to.

-- Alan Gibson (Alan@snibgo.com), February 09, 2000.

Ed, Here's something to try: Being also concerned about the impact of introducing a potentially dangerous substance into the environment,I decided simply not to and have been using the same solution of Selenium toner now for almost 2 years without disposing. I simply "replenish" by adding a few ounces of toner concentrate from the bottle when the toning becomes too slow. Carry over diminishes the volume slowly as well and every now and then I add water to make it up. So far, it has worked well with absolutely no side effects and I don't have to toss the environmentally suspect toner. I test the finished prints for residual hypo and silver and all pass the tests. I'd love to hear your thoughts on this. Regards, ;^D)

-- Doremus Scudder (ScudderLandreth@compuserve.com), March 01, 2000.