# Need experienced Ag.Refiners&Chemist thoughts



## darinventions (Dec 1, 2015)

Here's what happened...i had precipitated silver with copper as usual..began filtering an rinsing with distilled water an ran out of water in my sprayer...grabbed a jug of distilled water that was right behind me an refilled my spray bottle...well let me rewind to last week i was straightening up my lab an needed a heavy plastic jug..so i grabbed a jug of vinegar an poured the vinegar into a empty 1gal.distilled water jug....well here's how the incident happened..i unknowingly put vinegar in my spray bottle an began to hose it down with vinegar ...i soon realized what i did when i began to smell it...now this batch was almost done so i thought. i cleaned up my bottle an continued rinsing ..poured the solution with vinegar in it back in the cylinder beaker an put my sheet of copper back in it expecting not much to happen ..well it began precipitating quite heavily ..an before this happened it was bearly putting out anything ...can anyone explain what happened


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## butcher (Dec 1, 2015)

What happened chemically I can only guess, but what happened was you put vinegar in a solution where it was not needed, and had this been some other unknown chemical added by mistake you could have made a dangerous reaction, mixing chemicals in the lab can form very dangerous solutions be very careful about making this kind of mistakes in your lab.

Vinegar is not a very strong acid, but still somewhat acidic so it could have given your silver solution some free acid (hydrogen ions), or the organic portion of the vinegar could have given a neucleas for the reaction to begin, a reaction that would most likely have happened in due time anyway.
who knows what happened.


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## Lou (Dec 1, 2015)

You made silver acetate.

Silver acetate can simply be filtered off and melted. It will decompose to pure silver.
Silver acetate is slightly soluble, so continue to allow the silver to cement, it will just take longer.

Lou


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## darinventions (Dec 1, 2015)

Thank you very much Lou...You answered what i was asking..i really didn't need correction on mixing chem's because i keep everything hazardous labeled ..thats just good practice ..an vinegar is harmless ...it just got put by the water while cleaning up the lab....anyway as i said in the thead above the precipitation was almost complete i thought an if that's the case is it possible to extract more silver out of a solution that is thought to be done? An can you by chance explain the chemistry of what is taking place by using this method ?


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## Lou (Dec 2, 2015)

Test with Cl-. No precipitate means it's done and the Ag content below 2 mg/L.


Why everyone cements with copper is beyond me. Sometimes useful, yes, but if a person keeps their solutions concentrated in AgNO3, it's often better to add the stoichiometric requirement or slightly less of muriatic acid (do a titration, look up Volhard, an essential assay for anyone working with silver in quantity), get the AgCl and cement that with Fe/H2SO4.

Lou


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## upcyclist (Dec 2, 2015)

darinventions said:


> i really didn't need correction on mixing chem's because i keep everything hazardous labeled ..thats just good practice ..an vinegar is harmless



The folks around this forum are _very _safety-conscious. You might know better, but until we know you, we don't know that. Even if we know that, people will still make safety comments for the benefit of the other people who come by and only read what is written here. We have people that show up and say things like, "I don't have any nitric acid, but I do have some hydrofluoric acid. Can I use that instead?" :shock: 

As an aside, I'm currently doing PM recovery from old cyanide plating solutions. Before I can process the precipitate, I'm washing it to make sure all the CN- is gone. Vinegar is weak as acids go, but if I had grabbed it instead of water when I was washing NaCN precipitates, or rinsing out my reaction vessel, I might not be typing this now.


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## Lou (Dec 2, 2015)

Better safe than sorry.

Cyanide is a good example of applying that maxim--follow the rules, it works marvelous and is pleasant, don't and you're in trouble--*particularly if you can't smell it and don't know the warning signs.*

I suggest anyone doing CN work to have an antidote kit on hand, same thing if you deal with sulfides.


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## upcyclist (Dec 2, 2015)

Lou said:


> I suggest anyone doing CN work to have an antidote kit on hand, same thing if you deal with sulfides.



Good point. I tried looking for amyl nitrite earlier, but can't seem to find any. I'll be seeing my doc next week, maybe she has a solution. I'm at a pause in my processing anyway.

_Edit/Update_: Doh. It appears to be prescription-only. Guess I'll definitely have to talk to the doc. I can see it now: "Your cholesterol is high--you should consider Lipitor." "Can I have some poppers instead?"


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## Anonymous (Dec 3, 2015)

upcyclist said:


> _Edit/Update_: Doh. It appears to be prescription-only. Guess I'll definitely have to talk to the doc. I can see it now: "Your cholesterol is high--you should consider Lipitor." "Can I have some poppers instead?"



Well actually poppers would do exactly what the Amyl Nitrate does. :shock: :shock:


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## FrugalRefiner (Dec 3, 2015)

I believe he knows that. You may have missed our quirky US sense of humor! :lol: 

Dave


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## Anonymous (Dec 3, 2015)

Aww shucks I was trying to be humorous in reply Dave too. The Brit dryness strikes again old friend 8) 8)


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## FrugalRefiner (Dec 3, 2015)

Doh!!  

Dave


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## upcyclist (Dec 5, 2015)

Hehe, yup, that's why I referenced poppers--they _are _amyl nitrite.

Alas, the amyl nitrite (followed by IV sodium nitrite and sodium thiosulfate) is out of fashion as an antidote for cyanide poisoning, at least in the US. The currently favored tool is hydroxocobalamin, which is also administered via IV. That sucks for me, because I was specifically looking for something I can use while I wait for the ambulance.


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## SapunovDmitry (Feb 23, 2016)

My guess is that he killed some of the nitric (if the process was nitric based and it was in the beginning of the precipitation) with his vinegar and it helped because if there is some excessive nitric it will harm the precipitation process. Vinegar is the organic stuff and WILL be "burned" in nitric if added into the solution.


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