# Recover Silver From Fixer



## mda20 (Feb 28, 2013)

Hello friends,

Good Day! I would like to know if there is a chemical way to recover silver from concentrated fixer solution. I usually use a electrolysis unit. it is good. But I need to know if I can add some material to the fixer for recovery. 

I searched the forum, but no result.

Regards,
mda20


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## etack (Feb 28, 2013)

Your search function must not be working then. I type in the word "fixer"for these results. http://goldrefiningforum.com/phpBB3/search.php?keywords=fixer&terms=all&author=&sv=0&sc=1&sf=all&sk=t&sd=d&sr=posts&st=0&ch=300&t=0&submit=Search

Eric


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## mda20 (Feb 28, 2013)

Thank you Eric.

This link is useful for me. 
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=49&t=17017&p=172561&hilit=fixer#p172322

But not enough. If I will follow *Westerngs*`s way:



Westerngs said:


> If all you aretrying to accomplish is recover the silver, there is really no need to identify the type fixer you have. That would be close to impossible, as there are thousands of fixer types.
> 
> As for recovering the silver, there are several ways for you to go.
> 
> ...



I need to know how much zinc poweder I have to add?
And what does mean: *It would then require further refining to produce 0.999 silver*?

Regards,
mda20


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## etack (Feb 28, 2013)

You cement with zinc till you get no more reaction then you collect your precipitate and wash with a dilute sulfuric at about 10% to rid any excess zinc. similar to what you do with PMG powders when you cement them with zinc.

Eric


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## mda20 (Feb 28, 2013)

Thank you Eric

I will try your way. let me ask some questions please.

- How much zinc I will start with 5 liter of fixer?
- What you mean by *PMG powders*?
-Is there any risk when dealing with zinc?

Regards,
mda


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## Lino1406 (Feb 28, 2013)

Beware that fixers may get to you AFTER
silver removal. Asses silver presence
by precipitating with NaOH powder,
washing and analyzing. If positive
Do same for the whole lot.

Answer gold riddle No. 2 on
http://www.facebook.com/pages/Gold-electronic-enigma/162208933810735


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## mda20 (Mar 1, 2013)

Thank you *Lino1406* for posting.
I do not understand what you mean. Could you please give more details?


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## mda20 (Mar 4, 2013)

Good Day friends,

I am still wiating for more information. I would like to know if there is a chemical way to recover silver from concentrated fixer solution.

Regars,
mda20


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## Palladium (Mar 4, 2013)

Try sticking a piece of copper in the solution and if the silver cements on it use copper for recovery.


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## mda20 (Mar 4, 2013)

Thank you Palladium. I think this way wil be slow. Isn`t it!


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## jeneje (Mar 4, 2013)

mda20, i don't know what type of fixer you have, where it come from, but i done some photo fixer back when i first join here and i used NaOH (lye) to drop the silver. I don't think there is a fast way to do what you want, I have learned over the past dealing with precious metals of any kind - time seems to slow way down. 

The silver i dropped was in a brown to black mud, i decanted the solution claiming all the powder and washed several times, boiling in distilled water to remove the NaOH (lye). 

A word of *Caution* here is in order, do this outside or in a fume hood, the smell is unpleasent at the least, Also when using NaOH (lye) read the MSDS on lye. lye can effect your health several months down the road and can kill you, *DO NOT BREATH THE FUMES*. Hope this helps some.
Ken


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## mda20 (Mar 4, 2013)

Thank you jeneje



jeneje said:


> i don't know what type of fixer you have, where it come from,



It comes from medical x-ray films.



> i done some photo fixer back when i first join here and i used NaOH (lye) to drop the silver.



Adding NaOH will give black mud from which silver is hard to be recovered. 



> i decanted the solution claiming all the powder and washed several times, boiling in distilled water to remove the NaOH (lye).



How it will be washed if it is dissolved in the solution?

Regards,
mda20


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## jeneje (Mar 4, 2013)

My understanding at the time was the black powder was the silver, ready to melt. I may be wrong about this but that was my understanding at the time. I have never melted it and have somewhere put up. I now use copper to cement out my silver. 

Maybe someone can clarify this - this is a need to know for me also.
Ken

edited lye does not dissolve silver into solution it drops it out of solution.


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## Palladium (Mar 4, 2013)

I this sodium Thio?


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## Juan Manuel Arcos Frank (Mar 4, 2013)

mda20:

First of all,you have to know how many silver is in your fix.Let us see...

You can test your fix using the copper wire method,which is posted in this wonderful Forum.

Once you know how many silver is in 1 litre of fix you can add zinc dust...How many?,well,it depends on your silver concentration,as a rule of thumb add the same quantity of zinc as you have silver,I mean,if you have 6 gr/lt of silver in 5 liters of fix(which leads to 6 gr/lt x 5 lt=30 gr. of silver) then add 30 gr. of zinc dust.A dark mud will be formed which contains silver and zinc,so you need to refine it(by using Karo syrup process or any other refining process) to bring it to 0.999.


Does all above mentioned sound complicated?...Do not worry...you can use my sodium sulphide process to recover your silver,fast and easy and you can also use my process to convert silver sulphide into 0.999 silver.Both processes are posted right here...this why GRF is the best Forum in the world,isn´t it?.

I hope it helps.

Kindest Regards.

Manuel


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## goldsilverpro (Mar 4, 2013)

Manuel, you're back! I, for one, really missed you.


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## nickvc (Mar 5, 2013)

goldsilverpro said:


> Manuel, you're back! I, for one, really missed you.




I'll second that Chris..welcome back Manuel 8)


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## mda20 (Mar 5, 2013)

jeneje said:


> My understanding at the time was the black powder was the silver, ready to melt. I may be wrong about this but that was my understanding at the time. I have never melted it and have somewhere put up. I now use copper to cement out my silver.
> 
> Maybe someone can clarify this - this is a need to know for me also.
> Ken



You can find more details in this forum. Just search for "silver sulphide".


Dear Manuel, thank you for details. 


> you can use my sodium sulphide process to recover your silver,fast and easy and you can also use my process to convert silver sulphide into 0.999 silver.Both processes are posted right here



Does sodium sulphide will give metal silver?



> this why GRF is the best Forum in the world,isn´t it?.



Surly it is. I have been getting more and more from this great forum and from kind members here. Especially, Manuel, GSP and others. Thank you for all.


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## mda20 (Mar 8, 2013)

Dear kind Friends,

Good Day! After a long search I have found out the best way to recover silver from fixer. It is the zinc method. I will try it.


Best Regards,
mda20


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## etack (Mar 8, 2013)

Add zinc powder or shavings (bars are a wast of time and will strain your patients) till you get all the silver down(no more reaction) then rinse silver with hot water till it settle's nice. Next rinse with diluted HCl or sulfuric acids @ 10% this will rid your silver of any excess zinc powder.

Eric


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## mda20 (Mar 8, 2013)

Thank you Eric
I will follow your steps.

Let me ask you please. Have you tried NaOh + Sugar method?


Regards,
mda20


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## etack (Mar 8, 2013)

no but I have gone from AgCl to AgO with NaHO and directly melted it in a furnace and It went great.

Hope it works for you

Eric


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## Juan Manuel Arcos Frank (Mar 12, 2013)

GSP,My Dear Friend:

I am still here,reading all your post and trying to learn from your wisdom.

Have a nice day.

Your friend:

Manuel


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## Juan Manuel Arcos Frank (Mar 12, 2013)

nickvc:

Thanks a lot.

Kindest regards.

Manuel


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## Juan Manuel Arcos Frank (Mar 12, 2013)

mda20:

Sodium sulphide reacts with silver complex in fixer to form silver sulphide,which is a black and insolube mud that precipitates to the bottom of the container.Let settle down it,pour it off and dry it,now you can use my process to convert silver sulphide into metallic silver,if you do it well then you will get 0.999 silver.

Kindest regards.

Manuel


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## nh6886 (Jul 3, 2013)

mda20

Just checking to see how this turned out for you? I was wondering what method you used and of course if you had any glittery pictures to share with us.

Hope you're having fun
John


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## nh6886 (Jul 3, 2013)

Mda20

I had to add if you try the method Manuel mentions above its very rewarding. I know his advice is first to try the zinc method but I have to say my very best results are following his directions on the Ag2S route.


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## mda20 (Jul 9, 2013)

Thank you nh6886 for your post.

Please see my other post on this link:
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=50&t=18622


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## vitalclues (Aug 10, 2013)

I've still not been successful either with Zinc or Sodium sulphide though the sodium sulphide was a bit realistic. Pls can u once more step after step tell me what to really do.
How can I generate my own fixer and bleach?
How do I prepare 10% sulphuric acid solution?
Is sulphuric acid prepared in downing the PH?
What is the best PH for the solution?
Please be patient with my ignorance.
Thanks!
[email protected]


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## Buzz (Nov 2, 2013)

Hi,

Not trying to hijack MDA's thread but looking for some help with fixer solution.

I had a small amount of fixer solution, 1.5L, to which i added 5g of Sodium Sulphide.
I stirred and stirred but no reaction.
I heated the solution to "very warm" and stirred some more.
Still no obvious reaction so put it away until the morning.
Next day there was a creamy white coloured precipitate floating on the top.
Gave it a stir and the solids fell away to the bottom.
I filtered the solution and recovered the solids.
These will not dissolve in Nitric.

Can anyone tell me what i have here and why i did not get the expected black Silver Sulphide please?







Regards
Buzz


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## Juan Manuel Arcos Frank (Nov 2, 2013)

Buzz:

There is something wrong with your fixer...it seems that it does not contain any silver.

Reaction between silver complex in fixer and sodium sulphide takes place immediately.Did you check silver concentration in your fixer?.How many grams per liter do you have in your fixer?

Kindest regards.

Manuel


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## Buzz (Nov 3, 2013)

Hi Manuel,

When i tested the solution with a piece of copper, it took about 20 secs to get a fine coating on it.

I think maybe there is very little Silver in this batch for some reason.
Also, i was experimenting with only 1.5 litres.

Any idea what the cream coloured solids that appeared could be?

Regards
Buzz


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## Juan Manuel Arcos Frank (Nov 7, 2013)

Buzz:

Great Heavens!!!!!!!....you do not have any silver in your fixer.

As a rule of thumb,more than 5 seconds with no reaction means that silver concentration is too low and you should not process that kind of fixer.Come on,Buzz...try to find better fixers.

Kindest regards.

Manuel


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## Buzz (Nov 7, 2013)

I have a confession to make Manuel  

The guy that brought me the fixer......called me a couple of nights ago.
He said "Buzz, whatever you are doing to that fixer...stop right now!!...it's not fixer, it's developer!!" :roll: 

I've never seen fixer before (or developer for that matter) so i had no idea!
Seems someone had labelled up the container wrong.

Anyhow, he brought me some real fixer this afternoon and i dropped in some Sodium Sulphide and it all went to plan, just as you described, including the smell....holy cow! :shock: 

I've left it to settle overnight but i should have some Silver Sludge to play with in the morning.

Thanks for your patience Manuel, on here and via PM

Kind regards
Buzz


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## nh6886 (Nov 9, 2013)

Howdy Buzz

I hope you have as much success as I have enjoyed with this method, and Manuel's advice. I did however want to comment on the smell you mentioned. I know it's covered in lots of places here on he forum and elsewhere but since I didn't see it in this post I thought I would add a word of caution. That smell is H2S. I copied the information below from Wikipedia, although it is easy to find many places, they lay it out well. 
If you use Manuel's copper wire method to estimate the silver in your fix you have a very close starting point to know how much Sodium Sulfide to use. To find the exact amount with a new batch I take a 100 ml sample and add the estimated amount slowly then stir and let settle for a couple of minutes. I then add small amounts of sodium sulfide out of a scale dish that I start with 10 grams in. When the silver is all converted H2S starts to gas off. Along the way H2S will be produced at approximately 2ppm. With the last addition it goes up to about 6 or 8ppm. I reweigh the Sodium Sulfide in the dish and extrapolate the milligrams per liter to completely convert my silver.

If anyone sees corrections to be made please chime in.

An interesting perspective a safety trainer pointed out to me once is that when you're talking about ppm (parts per million) it's hard to visualize so he references the fact that 1ppm is an inch in 15.78 miles!

I do not discourage this method in any way but it needs to be done with full awareness.

All the Best,
John

Safety
Hydrogen sulfide is a highly toxic and flammable gas (flammable range: 4.3–46%). Being heavier than air, it tends to accumulate at the bottom of poorly ventilated spaces. Although very pungent at first, it quickly deadens the sense of smell, so potential victims may be unaware of its presence until it is too late. For safe handling procedures, a hydrogen sulfide material safety data sheet (MSDS) should be consulted.

Toxicity
Hydrogen sulfide is considered a broad-spectrum poison, meaning that it can poison several different systems in the body, although the nervous system is most affected. The toxicity of H2S is comparable with that of hydrogen cyanide or carbon monoxide.[12] It forms a complex bond with iron in the mitochondrial cytochrome enzymes, thus preventing cellular respiration.
Since hydrogen sulfide occurs naturally in the body, the environment and the gut, enzymes exist in the body capable of detoxifying it by oxidation to (harmless) sulfate.[13] Hence, low levels of hydrogen sulfide may be tolerated indefinitely.
At some threshold level, believed to average around 300–350 ppm, the oxidative enzymes become overwhelmed. Many personal safety gas detectors, such as those used by utility, sewage and petrochemical workers, are set to alarm at as low as 5 to 10 ppm and to go into high alarm at 15 ppm.
A diagnostic clue of extreme poisoning by H
2S is the discoloration of copper coins in the pockets of the victim. Treatment involves immediate inhalation of amyl nitrite, injections of sodium nitrite or administration of 4-dimethylaminophenol in combination with inhalation of pure oxygen, administration of bronchodilators to overcome eventual bronchospasm, and in some cases hyperbaric oxygen therapy (HBO).[12] HBO therapy has anecdotal support and remains controversial.[14][15][16]
Exposure to lower concentrations can result in eye irritation, a sore throat and cough, nausea, shortness of breath, and fluid in the lungs (pulmonary edema).[12] These effects are believed to be due to the fact that hydrogen sulfide combines with alkali present in moist surface tissues to form sodium sulfide, a caustic.[17] These symptoms usually go away in a few weeks.
Long-term, low-level exposure may result in fatigue, loss of appetite, headaches, irritability, poor memory, and dizziness. Chronic exposure to low level H
2S (around 2 ppm) has been implicated in increased miscarriage and reproductive health issues among Russian and Finnish wood pulp workers,[18] but the reports have not (as of circa 1995) been replicated.
Short-term, high-level exposure can induce immediate collapse, with a high probability of death. If death does not occur, studies have shown that, in humans, high exposure to hydrogen sulfide can lead to cortical pseudolaminar necrosis and degeneration of the basal ganglia. Cerebral edema have been shown in fatal exposures to hydrogen sulfide.

0.00047 ppm or 0.47 ppb is the odor threshold, the point at which 50% of a human panel can detect the presence of the compound.[19]

0.0047 ppm is the recognition threshold, the concentration at which 50% of humans can detect the characteristic odor of hydrogen sulfide,[19] normally described as resembling "a rotten egg".

OSHA has established a permissible exposure limit (PEL) (8 hour time-weighted average (TWA)) of 10 ppm.[20]

10–20 ppm is the borderline concentration for eye irritation.

20 ppm is the acceptable ceiling concentration established by OSHA.[20]

50 ppm is the acceptable maximum peak above the ceiling concentration for an 8 hour shift, with a maximum duration of 10 minutes.[20]

50–100 ppm leads to eye damage.

At 100–150 ppm the olfactory nerve is paralyzed after a few inhalations, and the sense of smell disappears, often together with awareness of danger.

320–530 ppm leads to pulmonary edema with the possibility of death.[12]

530–1000 ppm causes strong stimulation of the central nervous system and rapid breathing, leading to loss of breathing.

800 ppm is the lethal concentration for 50% of humans for 5 minutes exposure (LC50).

Concentrations over 1000 ppm cause immediate collapse with loss of breathing, even after inhalation of a single breath. 

Cortical pseudolaminar necrosis, degeneration of the basal ganglia and Cerebral edema have also been shown.[12]
Although respiratory paralysis may be immediate, it can also be delayed up to 72 hours.[23]


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## MysticColby (Nov 13, 2013)

why zinc for cementing silver in this case? (why not copper)?


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## butcher (Nov 13, 2013)

Normally zinc is chosen over copper when we want a more reactive metal, and one that will wash out of solution easier.

If we do not have a lot of base metals in solution with our values we may choose zinc over copper.

zinc is higher in the reactivity series of metals than copper, meaning there are many more base metals below it in the series that zinc will cement, as compared to copper, we also use this principle at times to choose to cement with copper so that we are not cementing out a large group of base metals with our values.


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