How to Recover silver from steel wool by yourself

MingMingPhoto · Jul 25, 2023

Hey guys, I'm running a small photo lab

I'm wondering how can we recover the silver we get from the steel wool. Right now we're sending it out, but I don't really trust the company at all.

What would the process be to recover that silver by hand?

Looking for something detailed and step by step

BrianShaw · Jul 25, 2023

I've never done this, but bookmarked this site a while ago; it might give you an idea...

How to Recover Silver from Waste Photographic Solutions

Table of Contents Metallic displacement-type silver recovery units are economical and practical for use by either large- or small-scale photographic processors. Most photographic processors could significantly increase their income by utilizing a unit of this type. The large-scale processor may...

www.911metallurgist.com

mshchem · Jul 25, 2023

You still need to refine the metal. Usually done in big quantities. I have a good friend who owns a coin and bullion shop. When he sends in scrap sterling silver (92% Ag) his usual box holds 40-50 lbs. He has enough that he gets a proper assay of the metal.

These steel wool appliances prevent pollution.

koraks · Jul 25, 2023

MingMingPhoto said:
I don't really trust the company at all.

Are you afraid that they just landfill the waste you bring to them?
If this is about the money you recover from the operation, I wouldn't be too optimistic. If you're going to DIY the refinement process, it'll be hard enough to break even on the cost of energy and materials on such a small scale. If you're getting paid for your silver now, this is also the reason why it's likely not much, if any at all.

mshchem said:
These steel wool appliances prevent pollution.

That's their primary rationale in a low-volume operation.

MingMingPhoto · Jul 26, 2023

koraks said:
Are you afraid that they just landfill the waste you bring to them?
If this is about the money you recover from the operation, I wouldn't be too optimistic. If you're going to DIY the refinement process, it'll be hard enough to break even on the cost of energy and materials on such a small scale. If you're getting paid for your silver now, this is also the reason why it's likely not much, if any at all.

That's their primary rationale in a low-volume operation.

If you're getting paid for your silver now this is also why it isn't much. This sentence doesn't make sense to me - can you explain how if we are making money from sending it out how it shows we wont make money if we do it our selves.

And no it's for money purpsoses not for landfill purpose - I don't see why the people taking our silver would throw it in a landfill + pay us for it

But yeah I know the start up cost would be something but in the long run it'll pay off, so I'm jsut tryna find out to recover silver from the steel wool step by step

koraks · Jul 26, 2023

MingMingPhoto said:
can you explain how if we are making money from sending it out how it shows we wont make money if we do it our selves.

Economies of scale.

Mr Bill · Jul 26, 2023

MingMingPhoto said:
I'm wondering how can we recover the silver we get from the steel wool. Right now we're sending it out, but I don't really trust the company at all.

Well, that trust is part of the issue, especially if you don't already have a pretty good idea of how much silver is, or should be, in the "steel wool" cartridge.

I can't tell you, beyond very generally, how to refine the silver. What I WOULD DO, though, is recommend changing to electrolytic silver recovery, IF this is feasible. This has the huge advantage that you can see, via weight, how much silver you actually have. The electrolytic flake has a very high purity if rinsed with water and dried, so very little question about what a refiner is dealing with. (You are still not gonna get a very good deal on this, given your relatively low volumes - you don't have much negotiating room.)

The main downsides of an electrolytic system are that it takes some skill in operating it, both in handling the fixer that you feed to it as well as operating the electrolytic cell itself. And... you will not be able to get ALL of the silver through this; you'll probably still need to use some sort of "tailing" system. And, a standard electrolytic system will not be able to handle blix (from paper processing), only fixer. There are too many details to list, but for the best recovery efficiency you need to build up a relatively high silver concentration in the fixer (this also means you are losing more silver to the wash water via carryover from the fixer). And you have to pay special attention to finishing up each electrolytic batch as the silver concentration gets low, meaning somewhere around 1/2 gram/liter. All told, you might be able to get around 80% of your silver, more or less, via an electrolytic system. (Higher is possible, but anyone who knows how to do this would not be asking questions on a general purpose photo forum.)

As with many other things this is a question of what compromises you wanna make, and where. If the effort and resources you might put into reducing costs of refining take away from efforts to improve the business then ...?

I do share your reservations about the steel wool cartridges though.

MingMingPhoto · Jul 27, 2023

Mr Bill said:
Well, that trust is part of the issue, especially if you don't already have a pretty good idea of how much silver is, or should be, in the "steel wool" cartridge.

I can't tell you, beyond very generally, how to refine the silver. What I WOULD DO, though, is recommend changing to electrolytic silver recovery, IF this is feasible. This has the huge advantage that you can see, via weight, how much silver you actually have. The electrolytic flake has a very high purity if rinsed with water and dried, so very little question about what a refiner is dealing with. (You are still not gonna get a very good deal on this, given your relatively low volumes - you don't have much negotiating room.)

The main downsides of an electrolytic system are that it takes some skill in operating it, both in handling the fixer that you feed to it as well as operating the electrolytic cell itself. And... you will not be able to get ALL of the silver through this; you'll probably still need to use some sort of "tailing" system. And, a standard electrolytic system will not be able to handle blix (from paper processing), only fixer. There are too many details to list, but for the best recovery efficiency you need to build up a relatively high silver concentration in the fixer (this also means you are losing more silver to the wash water via carryover from the fixer). And you have to pay special attention to finishing up each electrolytic batch as the silver concentration gets low, meaning somewhere around 1/2 gram/liter. All told, you might be able to get around 80% of your silver, more or less, via an electrolytic system. (Higher is possible, but anyone who knows how to do this would not be asking questions on a general purpose photo forum.)

As with many other things this is a question of what compromises you wanna make, and where. If the effort and resources you might put into reducing costs of refining take away from efforts to improve the business then ...?

I do share your reservations about the steel wool cartridges though.

So if I have the steel wool and I check the PH and determine it has a good amount of silver - would I wash off the woll and then melt the Wool at a specific temperature? If so what temperature would that be. How can I seperate the Iron from the silver?

MingMingPhoto · Jul 27, 2023

koraks said:
Economies of scale.

I see, I'll read it later but I still want to do this regardless

Mr Bill · Jul 27, 2023

MingMingPhoto said:
So if I have the steel wool and I check the PH and determine it has a good amount of silver - would I wash off the woll and then melt the Wool at a specific temperature? If so what temperature would that be. How can I seperate the Iron from the silver?

Hi, I don't think I was clear.

I'm NOT saying how to refine your iron/steel wool.

What I am suggesting is future use - that if you do enough processing to make it worthwhile that you obtain an electrolytic silver recovery unit. There IS a learning curve, and it cannot remove ALL the silver - you would still wanna follow up with an iron/steel wool cartridge. BUT... the electrolytic unit COULD get perhaps 70 or 80% of the silver.

Financially the electrolytic flake has high purity so refining costs are much lower than with a wool cartridge. Additionally you can look at, and weigh, the electrolytic flake so you have a very close idea how much is there. If you don't trust your refiner you tell them, here's the weight I measured, and DO NOT refine it if you get a different weight. After they refine it you KNOW that it should have a high purity, so if they report less than 90 or 95% pure you should perhaps look for a better refiner.

eli griggs · Jul 27, 2023

To be clear, tossing in a steel wool into a bucket of fixer starts the process of iron ions and silver ions exchanging places; the iron becomes just rust and, if done in a S. Steel bucket, the silver plates out to the SS bucket's inside, with the help of low power Electrolysis.

The recovered silver residue can then be banged of in large/ small pieces for further refinement.

I used a modified two 'C' cell flashlight to 'clean' copper fouling inside rifle barrels using an weak ammonia solution.

You could also lookup the portable Army darkroom trucks/modules that included a silver recovery incinerator, though how the temp was kept low enough to avoid vaporizing the freed silver, I do no know.

MingMingPhoto · Jul 27, 2023

Mr Bill said:
Hi, I don't think I was clear.

I'm NOT saying how to refine your iron/steel wool.

What I am suggesting is future use - that if you do enough processing to make it worthwhile that you obtain an electrolytic silver recovery unit. There IS a learning curve, and it cannot remove ALL the silver - you would still wanna follow up with an iron/steel wool cartridge. BUT... the electrolytic unit COULD get perhaps 70 or 80% of the silver.

Financially the electrolytic flake has high purity so refining costs are much lower than with a wool cartridge. Additionally you can look at, and weigh, the electrolytic flake so you have a very close idea how much is there. If you don't trust your refiner you tell them, here's the weight I measured, and DO NOT refine it if you get a different weight. After they refine it you KNOW that it should have a high purity, so if they report less than 90 or 95% pure you should perhaps look for a better refiner.

I appreciate you adding that info. I'd really jsut sim-ly like to know how to recover the silver from iron wool. This is all I'm trying to figure out. I'm runnign a small lab and want to give this a try. I appreciate all additional info, but I would like to emphasize that if you DO know HOW TO RECOVER THE SILVER FROM STEEL WOOL please please let me know.

eli griggs said:
To be clear, tossing in a steel wool into a bucket of fixer starts the process of iron ions and silver ions exchanging places; the iron becomes just rust and, if done in a S. Steel bucket, the silver plates out to the SS bucket's inside, with the help of low power Electrolysis.

The recovered silver residue can then be banged of in large/ small pieces for further refinement.

I used a modified two 'C' cell flashlight to 'clean' copper fouling inside rifle barrels using an weak ammonia solution.

You could also lookup the portable Army darkroom trucks/modules that included a silver recovery incinerator, though how the temp was kept low enough to avoid vaporizing the freed silver, I do no know.

I think I understand some of what you're saying. Thank you. I tried googleing the army thing and I think I foiund what you're talking about. But word, I aprpeciate you guys

koraks · Jul 28, 2023

MingMingPhoto said:
I'd really jsut sim-ly like to know how to recover the silver from iron wool.

The message from @Mr Bill boils down to "if you want to recover silver, don't use steel wool, but use electrolysis instead".
Introducing a truckload of iron into the process only complicates matters and results in making silver recovery more energy-intensive, and thus economically less attractive.

Have you tried the obvious step of contacting either FUJIFILM or Kodak about this question? They might be able to help.

MingMingPhoto · Jul 28, 2023

koraks said:
The message from @Mr Bill boils down to "if you want to recover silver, don't use steel wool, but use electrolysis instead".
Introducing a truckload of iron into the process only complicates matters and results in making silver recovery more energy-intensive, and thus economically less attractive.

Have you tried the obvious step of contacting either FUJIFILM or Kodak about this question? They might be able to help.

Ah ok ok I was wondering why everyone kept pushing that so hard.

But no I haven't contacted them, but hoenstly everytime I ask them questions no one really ahs any answers lol - espcially fujifilm. Buzz from Pakor, he's pretty knowledgable though so maybe I should ask him as well

thank you everyone

koraks · Jul 28, 2023

MingMingPhoto said:
espcially fujifilm

Next time I'm in touch with them I can see if I can get any directions from them. But I suspect I already know the answer: in-house recovery only makes sense if you're a high volume lab. They still might be able to give some directions about how to approach the matter from a technical viewpoint.

MingMingPhoto · Jul 28, 2023

koraks said:
Next time I'm in touch with them I can see if I can get any directions from them. But I suspect I already know the answer: in-house recovery only makes sense if you're a high volume lab. They still might be able to give some directions about how to approach the matter from a technical viewpoint.

do you suspect silver expires? I don't see why you can't jsut collect as much silver on the wool, or f elctolisis is so great through those means then process it when we have a huge load

koraks · Jul 28, 2023

MingMingPhoto said:
do you suspect silver expires?

No, I expect that the investments in tooling and operational costs (energy, manpower) will significantly outstrip the returns on silver recovered.

Have you run the numbers on how much silver you're effectively fixing/blixing out on a monthly basis and what the financial yields of a theoretical 100% recovery would be? That would at least give you a ballpark figure of what the maximum sensible cost level would be.

For instance, current Fuji papers have a maximum silver load of around 500mg/m2. Let's assume film will be four times as much (which will be on the optimistic side in all likelihood) at around 2g/m2. A single roll of film will be around 0.05m2. Assume you process 1000 rolls a month. Your theoretical silver recovery would be 50 * 2 = 100g. Let's assume $775/kg market price for a total monthly value of around $77.50.

In reality, you'll likely not be able to sell at market prices since no sane trader would accept your silver without the chance to run a profit on it themselves. So let's (optimistically) assume you can sell at 80% market value. Also, as per @Mr Bill 's suggestions, you may at best realize an 80% recovery rate in an operation of this scale. So those $77.50 are more like 50 bucks a month.

All told, this means that if you ignore any investment (which will be significant!) and you're spending 2 hours/month on the silver recovery chores, you'll still valuate your hours at only $25. Your location says NYC and frankly, that doesn't sound too swell for NYC standards especially if you factor in taxes etc.

Of course, you may decide that your hours aren't worth accounting for, that you might be able to set up a recovery system on a shoestring budget and 'borrowed' hours etc. etc. Such accounting decisions may make the whole thing more attractive - although the ceiling of the total amount of silver and its market value will be very firm, no matter how creative you are with the calculator.

This is just to offer a bit of a business perspective on the thing, using a paper napkin approach to get a feeling for the orders of magnitude. There are other arguments that may play a role for you as well, of course. For instance, perhaps you think it's fun to try and DIY this, in which case you might argue that as a hobby, it doesn't really matter if it makes business sense. But since I gather you're running a commercial operation, you might as well approach the issue from a commercial perspective, too. YMMV.

eli griggs · Jul 28, 2023

Trashed papers, film residues build up over time and if you are lucky enough to be given or buy for super cheap, very old, expired films and papers, your yield, come a distant processing time, should show some benefit.

At the least, use fixers that still have energy left to remove silver from prints/papers and films, trashed, expired, cutoffs, and pour them into a large, outside warm months, evaporation jug, so you end up with some black silver sludge for silver recovery.

Until we start harvesting space born silver and gold, etc, or perhaps bottom of the ocean nodules of the same, silver should no be getting too cheap to harvest from our hobby/works.

IMO.

Don_ih · Jul 29, 2023

I don't see why you wouldn't be able to melt the silver off the steel wool. Buy a propane torch.

foc · Jul 29, 2023

When I had a minilab we used one of these machines

https://www.metafix.co.uk/electrolytic-silver-recovery-mbx

All liquid photographic waste was put through the unit, every night. The machine was approved and licensed by the local EPA so that the wastewater could enter the local sewer system.

I received no money for the recovered silver as the machine was supplied by the agent for a nominal fee. When the cartridge was changed, the agent sent it away and he received any silver recovery money.

It suited me perfectly as basically, it cost me nothing to be EPA compliant. If I was to do it myself, it involved a lot of paperwork, licenses and inspections, effluent samples and lab tests.

The OP may have different local EPA requirements.

MingMingPhoto · Jul 29, 2023

koraks said:
No, I expect that the investments in tooling and operational costs (energy, manpower) will significantly outstrip the returns on silver recovered.

Have you run the numbers on how much silver you're effectively fixing/blixing out on a monthly basis and what the financial yields of a theoretical 100% recovery would be? That would at least give you a ballpark figure of what the maximum sensible cost level would be.

For instance, current Fuji papers have a maximum silver load of around 500mg/m2. Let's assume film will be four times as much (which will be on the optimistic side in all likelihood) at around 2g/m2. A single roll of film will be around 0.05m2. Assume you process 1000 rolls a month. Your theoretical silver recovery would be 50 * 2 = 100g. Let's assume $775/kg market price for a total monthly value of around $77.50.

In reality, you'll likely not be able to sell at market prices since no sane trader would accept your silver without the chance to run a profit on it themselves. So let's (optimistically) assume you can sell at 80% market value. Also, as per @Mr Bill 's suggestions, you may at best realize an 80% recovery rate in an operation of this scale. So those $77.50 are more like 50 bucks a month.

All told, this means that if you ignore any investment (which will be significant!) and you're spending 2 hours/month on the silver recovery chores, you'll still valuate your hours at only $25. Your location says NYC and frankly, that doesn't sound too swell for NYC standards especially if you factor in taxes etc.

Of course, you may decide that your hours aren't worth accounting for, that you might be able to set up a recovery system on a shoestring budget and 'borrowed' hours etc. etc. Such accounting decisions may make the whole thing more attractive - although the ceiling of the total amount of silver and its market value will be very firm, no matter how creative you are with the calculator.

This is just to offer a bit of a business perspective on the thing, using a paper napkin approach to get a feeling for the orders of magnitude. There are other arguments that may play a role for you as well, of course. For instance, perhaps you think it's fun to try and DIY this, in which case you might argue that as a hobby, it doesn't really matter if it makes business sense. But since I gather you're running a commercial operation, you might as well approach the issue from a commercial perspective, too. YMMV.

I see what you're saying, be the reason I'm asking if silver expires is becasue at the end of the day if I store up a butt load of wools from over the years and pick a day one, two, three years own the line and decide today is smelting day it'll totally be worth it. It'll also be worth is casue it'll be fun (in the beginning) and when it stops beign fun we can jsut do it three years down the line instead of every year. I jsut checked and we process about 1000 rolls a month - 95% c41. We use RA chemicals so we fix seperatly from bleach.

The guy whom we currently send our silver to said he was able to recover 400$ of silver from our one year batch of wool. He's only going to pay us 100 for it though, but I asked him If I could buy what he smelted and he said no, so I thought that was pretty strange - sounded like a red flag to me.

Part of this is also just nerding out and learning more about the photographic process. also our lab is half community darkroom so we can all learn together.

Also I feeeeeel like the investment won't be TOO crazy, something under 1000 I'm sure. How much can a torch, a container to put the hot metal, and some misc. tools come up to? The trouble is finding out what I need exactly and how to start that process. I'll prob call some smelters I can find on yourtube who are out of state and see if they'd be willing to explain

but yes! If you do get an answet from fuji please let me/us know!!

eli griggs said:
Trashed papers, film residues build up over time and if you are lucky enough to be given or buy for super cheap, very old, expired films and papers, your yield, come a distant processing time, should show some benefit.

At the least, use fixers that still have energy left to remove silver from prints/papers and films, trashed, expired, cutoffs, and pour them into a large, outside warm months, evaporation jug, so you end up with some black silver sludge for silver recovery.

Until we start harvesting space born silver and gold, etc, or perhaps bottom of the ocean nodules of the same, silver should no be getting too cheap to harvest from our hobby/works.

IMO.

Are you saying that if we jsut let the fixer evaporate we'll be left with metalic silver? I seen something about this, but doens't it matter what kidn of fixer? Not the evaporation part but silver begining to stick to the edges of the container -- or rather the walls of the container

Don_ih said:
I don't see why you wouldn't be able to melt the silver off the steel wool. Buy a propane torch.

Yeah I think this is what I'm expecting to hear. I just wanna be safe and proper. Idk if burnign will make some dangerous gas, etc. Also I heard somewhere iron melts at a way hotter temp so getting the silver should be light work. Just wondering how, how sway

foc said:
When I had a minilab we used one of these machines

https://www.metafix.co.uk/electrolytic-silver-recovery-mbx

All liquid photographic waste was put through the unit, every night. The machine was approved and licensed by the local EPA so that the wastewater could enter the local sewer system.

I received no money for the recovered silver as the machine was supplied by the agent for a nominal fee. When the cartridge was changed, the agent sent it away and he received any silver recovery money.

It suited me perfectly as basically, it cost me nothing to be EPA compliant. If I was to do it myself, it involved a lot of paperwork, licenses and inspections, effluent samples and lab tests.

The OP may have different local EPA requirements.

Thank you for sharing! I hoenstly want to avoid the elctrolisis method - it seems like there's a lot to it. The steel wool method seems more strightforward but thank you regardles for hsaring. If I go with this method I'll look back at this link

koraks · Jul 30, 2023

MingMingPhoto said:
I hoenstly want to avoid the elctrolisis method - it seems like there's a lot to it. The steel wool method seems more strightforward

Simply put, the steel wool method & blow torch will give you crap purity that'll be difficult to sell, the electrolysis method gives good purity. In theory the difference shouldn't be there, but in reality you're going to trap all sorts of crud and dirt in your silver by blowtorching it off of steel wool. Keep in mind the steel wool itself will burn when blowtorched. You'll end up with silver with a crapload of iron oxide trapped in it. It'll be a mess, but by all means give it a try. Even if it's a failure in terms of purity, the silver will still be there.

MingMingPhoto said:
Are you saying that if we jsut let the fixer evaporate we'll be left with metalic silver?

And some other organic compounds. But it'll be easier to separate out the silver in a thermal process this way, essentially burning away all the organics that you'll also be left with.

eli griggs · Jul 30, 2023

MingMingPhoto said:
I see what you're saying, be the reason I'm asking if silver expires is becasue at the end of the day if I store up a butt load of wools from over the years and pick a day one, two, three years own the line and decide today is smelting day it'll totally be worth it. It'll also be worth is casue it'll be fun (in the beginning) and when it stops beign fun we can jsut do it three years down the line instead of every year. I jsut checked and we process about 1000 rolls a month - 95% c41. We use RA chemicals so we fix seperatly from bleach.

The guy whom we currently send our silver to said he was able to recover 400$ of silver from our one year batch of wool. He's only going to pay us 100 for it though, but I asked him If I could buy what he smelted and he said no, so I thought that was pretty strange - sounded like a red flag to me.

Part of this is also just nerding out and learning more about the photographic process. also our lab is half community darkroom so we can all learn together.

Also I feeeeeel like the investment won't be TOO crazy, something under 1000 I'm sure. How much can a torch, a container to put the hot metal, and some misc. tools come up to? The trouble is finding out what I need exactly and how to start that process. I'll prob call some smelters I can find on yourtube who are out of state and see if they'd be willing to explain

but yes! If you do get an answet from fuji please let me/us know!!

Are you saying that if we jsut let the fixer evaporate we'll be left with metalic silver? I seen something about this, but doens't it matter what kidn of fixer? Not the evaporation part but silver begining to stick to the edges of the container -- or rather the walls of the container

Yeah I think this is what I'm expecting to hear. I just wanna be safe and proper. Idk if burnign will make some dangerous gas, etc. Also I heard somewhere iron melts at a way hotter temp so getting the silver should be light work. Just wondering how, how sway

Thank you for sharing! I hoenstly want to avoid the elctrolisis method - it seems like there's a lot to it. The steel wool method seems more strightforward but thank you regardles for hsaring. If I go with this method I'll look back at this link

No, no metallic silver like that in a silver coin or spoon, but the collected sludge which is processed, melted down with heat, into a metallic silver.

BrianShaw · Jul 30, 2023

https://pubs.usgs.gov/of/2004/1251/2004-1251.pdf

https://www.ijltemas.in/DigitalLibrary/Vol.7Issue7/80-87.pdf

https://patentimages.storage.googleapis.com/fb/1b/8e/88f98c7d0a243a/US5244777.pdf

US5958657A - Regeneration of spent fixer solution - Google Patents

A process for regenerating spent fixer solution which includes the steps of adding finely particulate zinc, such as zinc dust, to the solution to cause silver dissolved therein to precipitate and removing the precipitate from the solution hereby producing a regenerated fixer solution.

patents.google.com

BrianShaw · Jul 30, 2023

MingMingPhoto said:
...

The guy whom we currently send our silver to said he was able to recover 400$ of silver from our one year batch of wool. He's only going to pay us 100 for it though, but I asked him If I could buy what he smelted and he said no, so I thought that was pretty strange - sounded like a red flag to me.

Part of this is also just nerding out and learning more about the photographic process. also our lab is half community darkroom so we can all learn together.

,,,

I completely understand how difficult it is to think of the processor keeping 75% of the yield, they hold the knowledge and processes to perform the work. Just the other day I took similar matters into my own hands by replacing a Honda windshield visor myself. The part cost some money but the labor was simply criminal. About $100 to do a 5 minute task. But it took me a couple of hours to google and youtube and fiddle with it to learn the secret that thy know and I didn't. Was it worth it... to me, definitely!

I'm glad that you are in "nerding out" mode; so am I. Earlier inthe thread I posted what looks like a step-by-step process that is not electrolisys. That, however, appears to require a kiln/furnace. None of these processes seem really easy to really go from used fixer to a bar of assayed silver. Post 24 is a few items I found that I thought a fellow nerd might want to read. The diversity of opinion on which process is best/efficient is quite interesting, as are some of the methods described.

How to Recover silver from steel wool by yourself

MingMingPhoto

BrianShaw

How to Recover Silver from Waste Photographic Solutions

mshchem

koraks

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MingMingPhoto

koraks

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Mr Bill

MingMingPhoto

MingMingPhoto

Mr Bill

eli griggs

MingMingPhoto

koraks

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MingMingPhoto

koraks

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MingMingPhoto

koraks

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eli griggs

Don_ih

foc

MingMingPhoto

koraks

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eli griggs

BrianShaw

US5958657A - Regeneration of spent fixer solution - Google Patents

BrianShaw

How to Recover silver from steel wool by yourself

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