# Dropping silver from sufuric stripping cell.



## qst42know (May 14, 2009)

I know this topic has been discussed at length in several other threads with mixed results. One member had some success stripping silver plate when the solution cooled the sediment recovered and treating the silver with salt.

However I ran across this process. The Gutzkow process beginning on pg. 409

http://books.google.com/books?id=WRsNAAAAYAAJ&pg=PA409&lpg=PA409&dq=Gutzkow+process&source=bl&ots=KDEwwzhj-E&sig=8O9eWd4NXSaznyYhh0g4JRISPDA&hl=en&ei=mV0LSu_oO52xmAf-rZDzCw&sa=X&oi=book_result&ct=result&resnum=1#PPA409,M1

The Gutzkow process is for parting gold and silver dore by boiling in sulfuric. 

But can it be adapted.

After reading the process is it chemically possible to drop the silver from the sulfuric with ferrous sulfate leaving the sulfuric acid to be reused?

Does the Gutzkow process work because of the temperature change in a saturated solution?

I have read this process several times but I'm not sure I understand how it works or if it will work adding ferrous sulfate to the electricaly stripped silver solution.


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## qst42know (May 20, 2009)

As near as I can figure this process relies on the silver being soluble in concentrated sulfuric but much less so in dilute sulfuric acid. The silver sulfate dropped when they introduce the steam.

As a question to those more fluent in chemistry than I, does the ferric sulfate produced from boiling in the iron vessel reduce the silver sulfate to metallic silver? or does this process really just burn the sulfur off in the melt?

I realize this is an old primitive method but is there something more to this?


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## beaks (May 20, 2009)

look here (pretty good vids)
http://www.goldrecovery.us/


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## Lou (May 21, 2009)

This method capitalizes on 1.) the high temperature that concentrated sulfuric can be maintained at, 2.) its oxidizing properties when hot, 3.) stabilizing and solubilizing effects when hot and concentrated, with regards to Ag2SO4. 


Ferrous sulfate is indeed the reducing agent, but it's at high temperature that this works (very slow at room temp.).


EDIT: ferrous sulfate was used in the old process, the improved process as cited in the book does a hot reduction using charcoal and a mixture of Ag/Ag2SO4.


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## qst42know (May 21, 2009)

Thank you, Lou. 

Your insights into this process make it a much easier read.

This seems like a very dangerous occupation for $2-$2 1/2 per day. Kind of makes you appreciate the origins of labor unions.


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## Lou (May 21, 2009)

I'd certainly hate to fall into a vat of nearly boiling sulfuric acid.

Couple that with the fact that sulfuric acid mist is a known human carcinogen.


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