Recycling precipitated silver in old fixer?

[Rob Tucher]

Philippe, it may be frustrating to ask a question and not get a specific answer but a forum is give and take and it by nature goes where it goes. The answer to your question is pretty complicated but some of it is inside these responses. You can gather silver through a number of means. Electrolytic machines are available and collect silver plate on either the anode or cathode, I forget which, and then you scrape it off. I got one on Ebay.

The precipitate type of collector can get expensive and involved and is usually meant for large users of chemistry, but basically is the steel wool replacement type. If you don't run a huge amount of chemistry through these then the steel wool corrodes and crumbles before you can collect and it's a waste. There are small steel wool pour-through types of buckets for low volume (just gravity feed rather than pump).

The problem with all the types is that the refining end of it is the complicated part. I'm not sure how you could. It takes baking to dry sludge, then firing at high temperatures to separate, and then a few more steps. I visited a refiner and he walked me through the plant and it is a big, costly operation just to get down to the basics.

Look up silver refining and silver recovery and explore the potential with them. They may tell you it isn't possible or have some hints. The guy I sell my stuff to is very helpful and open.

Jake, you're very right. Ignorance of the law has never been a defense. And it IS NOT limited to commercial only, Phil. The guy I was talking about was not a pro and did nothing commercial. Heavy metals are heavy metals no matter what the source and unless you live in a very lax area you're taking a big chance assuming you won't get caught.

[Philippe Gauthier]

Thanks Rob, you're a champ. You don't hve all the answers, but at least these are useful starting points. I had no idea this whole thing was so complicated - and the US law so difficult to comply with because there is little technology available.

[Wayne]

and the US law so difficult to comply with because there is little technology available.

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Not hard at all, you simply dispose of used fixer at a hazardous waste facility if you cant de-silver it. In my area disposal is free for non-commercial users.

[John_6081]

I am a professional in this field. I have been recovering silver for the labs for 23 years now.
should you need a help contact me at allaboutelectric@peoplepc.com

[Richard Ide]

Hi Phillippe

Silver recovered from fixer will have impurities in it. I would buy silver nitrate ready to use. Generally, photographic chemicals are very pure so as not to introduce contaminants which might have an adverse effect upon a process. Iron is one metal which must be avoided completely.
When I was recovering silver a few years ago, I was paid for about 85% of the weight I collected. I remember when the Ontario Ministry of the Environment made it necessary to register as a hazardous waste generator. If I recall, (please check) personal use at home by photographers was unregulated because of the very small quantities involved. If selling recovered silver, one would probably run in to problems not being licenced and not profitable unless you had at least a couple of hundred ounces. I recover silver at home from spent fixer just to keep it out of the environment. Nitric acid can be nasty stuff so I would avoid trying to do it myself.

Richard

[N Dhananjay]

Porters camera (www.porters.com) sells a silver recovery unit that is small and reasonably priced. Cheers, DJ

[n aveed b utt]

hello, Sir

I want to know How I can meaure the exact quantity of silver in waste chemical

did u have any method or equipment pls tell me,

I know only copper test,

Thanks,

[Richard Ide]

Kodak supplied fixer test strips in a booklet. You would tear a strip off and immerse the end in the fixer. The colour would change as the concentration of silver increased. There was a colour chart printed on the back of the book. You matched the colour of your strip to the chart and the concentration in ounces per gallon or grams per litre was given for that particular concentration