holybull95 - 12-9-2006 at 10:48
I need to turn a small amount of silver nitrate powder in something that can be thrown away without hurting the environment. I was told by someone
that making it into a solution with water, adding an equal molar quantity of KI and drying it back into a powder should do the trick. Is this true? Is
there a bertter way?
Thanks,
Gary
Polverone - 12-9-2006 at 10:58
What about using a sodium ascorbate solution from Vitamin C and baking soda? You should actually be able to recover the silver metal as a dark powder
that way. Or you can just throw it away without recovery. The KI will immobilize the silver ions too.
garage chemist - 12-9-2006 at 11:25
You can simply heat the silver nitrate to the melting point of silver metal. The AgNO3 will decompose, and after cooling you will have a pellet of
pure silver.
Eclectic - 12-9-2006 at 14:03
Dissolve it in water and mix it with salt water if it's just a small amount. Silver chloride will precipitate and can be collected to recover the
silver. A small amount should be ok to flush down the
toilet.
neutrino - 12-9-2006 at 14:21
Why sodium ascorbate? Just plain ascorbic acid (Vit C) will reduce soluble silver ions to the metal almost immediately.
12AX7 - 12-9-2006 at 14:51
Sodium ions keep a handle on the nitrate ions.
Tim
The_Davster - 12-9-2006 at 19:06
Just toss some copper wire in. Get a nice tree of silver which can be recovered, and the copper nitrate solution resulting is fine to discard.
Copper sulfate is used for removal of roots from drainage lines after all.
[Edited on 13-9-2006 by rogue chemist]
woelen - 12-9-2006 at 22:37
The best way to get rid of the stuff is to make someone else happy with it 
.
I'm quite sure there are members over here in your country who would be glad to receive some silver nitrate and are willing to pay the postage.
Tacho - 13-9-2006 at 03:50
Silver is not toxic and doesn't hurt the environment. But to discard it's salts is plain stupid. They are expensive.
1- Rogue chemist sugestion is the best. Quick and dirty.
2- Add a solution of table salt to a solution of AgNO3 and you have a white silver chloride precipitate. Mix this precipitate with a strong solution
of lie (NaOH, let's say 30%) and table sugar (sacarose). Heat while stirring and silver powder will precipitate. Wash the silver powder. This works
great.
3- The ascorbate/vitamin C idea also works, but vitamin C is not as cheap.
Powdered silver can be:
1-stored;
2-mixed with ethyl acetate (or acetone) and polystirene plastic (just a bit) to make conductive paint.
3-mixed with water and some organic binder to make "silver clay". I never tried this one though. Check the link:
http://en.wikipedia.org/wiki/Precious_Metal_Clay
Silver chloride powder, mixed with some table salt and a binder like kaolin can be used to plate copper. Just rub strongly the humid (almost dry)
paste on the clean copper surface and it takes a silver covering. You must rub strongly to obtain a shiny, resistant silver coating. I use this when I
need my printed circuits to make good, oxidation free, contact.
[Edited on 13-9-2006 by Tacho]