# recover silver from old fixer sludge



## ockeller (Jan 17, 2011)

I have access to approx 15 gal of old, concentrated (approximately 100-150gal originally) fixer that have been sitting around evaporating for years. Some is black liquid with a gray sediment (about .5" deep) in the bottom of 5 gal jugs. Some have the sediment below a yellow/orange "cloud" with clear liquid on top. What is the best way to recover the silver? Plate?

There is also a lump (appox 1 lb) of fused material that came from the bottom of 1 of the jugs that completely dried out. Owner tried melting but the fumes convinced him he didn't want to do it. What is the best way to process this "lump"?

Thanks!


----------



## luigi2004 (Jan 19, 2011)

Hi !!!!
First, excuse me for my bad english
With the lump (silver sulphide), make a fine powder and then mix it with iron filings (20% in weight) Melt it and then pour it in a V shaped iron cast.(to avoid accidents you have to heat it up before pouring the silver)
When it cools, broke the dark glass with a hammer and you will find in the bottom a coarse lump of silver.
With clear liquid on the jugs, analyze it for Ag with a drop of Sodium sulphide.
The gray sediment is also silver sulphide.
Or you can search in this forum for silver sulphide – look for Manuel Arcos Frank, who gots different metods for the silver recovery from the silver sulphide
Good Luck
Luis


----------



## Juan Manuel Arcos Frank (Jan 20, 2011)

Wonderful method,Luis!!!!!!!!!!....

Kindest regards

Manuel


----------



## ockeller (Jan 21, 2011)

THANKS! I'll give it a shot and post my results. If silver in the liquid, what's the best way to recover - boil it out and recover the silver sulfide?


----------



## luigi2004 (Jan 21, 2011)

Hi Manuel:
Thank you so much for your post.
It is most gratifying for me to have a recognition from whom I name Mr Silver Sulphide.
With my best regards and respect for your knowledge
Luis


----------



## luigi2004 (Jan 21, 2011)

Hi Ockeller:
Since you are dealing with silver sulphide I think that you must precipitate the remaining silver with sodium sulphide so you don't need to mess with the desilvering machine.
Personally I don't think that there is any silver remaining in the fixer due to the long time that it have been sitting around.
You do not need to boil the fixer
If you do not have the sodium sulphide “burn” the fixer with two graphite rods from an old 1,5 volts battery .
Put both rods in the fixer spaced 4 inches between them.
Apply with a 110 / 6 volts transformer with a rectifier bridge until not more black precipitate falls in the bottom of the container where you are doing the electrolysis. 
Then wash and dry the silver sulphide and mix it with the gray sediment that you previously have dried.
Broke the dried silver sulphide until it is reduced to a fine powder and then mix it very thoroughly with the iron filings (as more fine are the iron filings, less sulphur odor will surge from the crucible when you melt it)
The yield is approximately 20/25% in weight
Any question, don't hesitate to post it.
Be very careful when you pour the melting silver ; use a protection for your eyes 
Again good luck
Luis


----------



## nickvc (Jan 22, 2011)

Luigi if English isn't your first language may I say I can follow and understand your posts better than some members who's only language is English.
Well done I think your going to be a valuable member of the forum. 8)


----------



## luigi2004 (Jan 23, 2011)

Thank you so much Nick vc for your kind post.
I try to be the most didactical or explanatory or eloquent (If those are the right words) in a way to be grateful with all the people who are part of this wonderful forum.
But I make mistakes or omissions as you will see.
I forgot in my first post two steps :
The first one is when you mix the silver sulphide with iron filings add roughly the same weight in soda solvay in order to make the reaction smooth and to protect the crucible.
The second one is when you heat up the iron cast (until it takes a dark red color)
you have to pour over the iron cast some old oil car.
As soon you pour the oil over the cast, it will ignite forming a carbon layer over the cast that will make more easier to get out the glass from the cast.
I put the cast upside down with the pliers and beat it in the back with the the hammer until the glass fells.
Thank you again and a hug for all of you
Luis


----------



## Juan Manuel Arcos Frank (Jan 24, 2011)

Luis:

Thank you for your kind post,one day I will understand all silver´s sulphide secrtets,I hope.

BTW I forgot to say that sludge could be treated with AR or "Chlorox process",both turn it to silver chloride then you can melt silver chloride with sodium carbonate.

Luis,where do you live?

Regards.

Manuel


----------



## luigi2004 (Jan 24, 2011)

Hi Manuel:
I live in Buenos Aires , Argentina. 
I am a radiographer and I take the silver recovery as a second work (Cash and no taxes).
May I ask you a question regarding your method of the sodium hyposulfite + SO4Cu?
When I read “Precious metal recovering gives me money,women take it away from me" it reminds me of a saying here in Argentina : “Beware of the fast women and the slow horses”
Luis


----------



## Juan Manuel Arcos Frank (Jan 26, 2011)

Che Luis:

Great Heavens!!!!!,Argentina...Buenos Aires...churrasco(a kind of beefsteak),chimichurri(a kind of sauce),mate(a traditional Argentine beverage),alfajores(a kind ok sweet cake) and the beauty of Argentine women that is recognized worldwide!!!!!!.

About ammoniun/sodium thiosulphate(that you have called "sodium hyposulfite")+ copper sulfate is refered as a complex salt that dissolves silver sulfide and you can prepare it very easy...just add a pinch of CuSO4 to common 1 liter of X Ray fixer and you can dissolve silver sulfide.I am an honest thief,this process is not mine,it belongs to a nice gentleman named Mr. Russell who invented it 150 years ago.

Luis,behave yourself.

Regards.

Manuel


----------



## luigi2004 (Jan 28, 2011)

Hi Manuel:
God bless Mr Russell
Whe you say a pinch, could it be 5% in weight ? 
Have you been in Bariloche ?
Did you test the dulce de leche? (A kind of milk syrup)
Muchos saludos
Luis


----------



## Juan Manuel Arcos Frank (Jan 29, 2011)

Luis:

Yes,Sir,5% is OK.

Someday I will go to Argentina when my lawyers and pension debts let me go.I like dulce de leche but I prefer alfajores.

Kindest regards.

Manuel


----------



## ockeller (Feb 25, 2011)

I apologize for the long delay in responding. Been very busy with the day job and have been doing a lot of reading on the forum before I started! Just want to be safe...!!!!

I would like to thank you all for the wonderful help (and great forum, too!). Gave it a whirl per your suggestions over the last couple of days and VIOLA, silver! Not as much as I thought, but, hey, what a great feeling when the glass floated to the top of the mold and broke off with a hammer. Dissolved in nitric and cemented with copper. Gray mud when melted turn that wonderful silver color! By the way, silver sulfide dropped out of the old fixer with sodium sulfide and did yield approx 22% by weight silver.

Think I will go the next step and try & build an electolytic cell...Time for some more research on the site.

Thanks again, mi amigos!


----------

