holybull95
Harmless
Posts: 1
Registered: 12-9-2006
Member Is Offline
Mood: No Mood
|
|
How to render silver nitrate harmless?
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
Now celebrating 21 years of madness
Posts: 3186
Registered: 19-5-2002
Location: The Sunny Pacific Northwest
Member Is Offline
Mood: Waiting for spring
|
|
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.
PGP Key and corresponding e-mail address
|
|
garage chemist
chemical wizard
Posts: 1803
Registered: 16-8-2004
Location: Germany
Member Is Offline
Mood: No Mood
|
|
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
National Hazard
Posts: 899
Registered: 14-11-2004
Member Is Offline
Mood: Obsessive
|
|
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
International Hazard
Posts: 1583
Registered: 20-8-2004
Location: USA
Member Is Offline
Mood: oscillating
|
|
Why sodium ascorbate? Just plain ascorbic acid (Vit C) will reduce soluble silver ions to the metal almost immediately.
|
|
12AX7
Post Harlot
Posts: 4803
Registered: 8-3-2005
Location: oscillating
Member Is Offline
Mood: informative
|
|
Sodium ions keep a handle on the nitrate ions.
Tim
|
|
The_Davster
A pnictogen
Posts: 2861
Registered: 18-11-2003
Member Is Offline
Mood: .
|
|
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
Super Administrator
Posts: 8014
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
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
National Hazard
Posts: 582
Registered: 5-12-2003
Member Is Offline
Mood: No Mood
|
|
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]
|
|