refiner123
Member
- Joined
- May 13, 2020
- Messages
- 16
Hi
I bought a set of lab equipment from a bankrupt company. The lot had many useful pieces for newbie home refiner. (beakers, erlenmeyers, magnetic stirrer, buchner funnels, vacuum flasks, vacuum pump, etc)
When collecting the stuff I had bought, I found two thick walled large (~20 liter) plastic containers labeled silver oxide. I thought that those would be great for waste liquid storage so I picked them up rather than throwing to trash.
The containers did not contain any leftover liquid, but at least one of them contains large clumps of white powder.
The primary reagents used in this lab seemed to be hydrochloric acid, sodium hydroxide and sodium thiosulfate.
My guess is that the white powder could be silver chloride. (somebody rinsed silver oxide container with HCl?)
Both of the containers have black coating on their inside.
I am wondering whether there would be any reasonable way to recover the silver oxide layer from the containers before using them as waste liquid containers. Even though the layer is completely black, it is probably very thin.
I have thought out couple of options:
1) dilute nitric acid.
Nitric will dissolve silver oxide to silver nitrate. The challenge is how to rinse all the container walls without
using large amount of acid. Nitric acid is expensive and expected amount of recovered silver is very small.
I can reuse some amount of leftover nitric acid to refine silver recovered via electrolysis.
Nitric rinse creates NOx gas and due to the size of these containers it might be hard to do this rinse safely.
Nitric won't dissolve any silver chloride clumps from the bottom of containers.
I probably won't be able to get all of the assumed silver chloride out of the containers before the acid rinse.
Nitric acid rinse could contain both: silver nitrate and silver chloride. Need to either separate them by filtering and process separately or convert all to chloride.
2) sulfuric acid
According to many sources, sulfuric acid reacts with silver oxide to create silver sulfate.
Ag2O + H2SO4 -> Ag2SO4 + H2O
This reaction won't create toxic NOx fumes.
Dilute sulfuric acid is available with more reasonable cost as battery acid.
Can somebody enlighten me whether this reaction works with dilute sulfuric acid or does it require concentrated sulfuric acid?
Metallic silver requires concentrated sulfuric acid, but this should be oxide.
Silver sulfate is slightly soluble in warm water.
Would it be possible to recover the silver using small amount of battery acid diluted with warm water?
Silver sulfate can be converted to silver chloride with NaCl or HCl and processed with the assumed silver chloride.
I don't expect to recover pure silver with this method, but I could combine the recovered metallic silver to the silver recovered via electrolysis, which I will refine with nitric acid in the future.
Sulfuric won't dissolve assumed silver chloride clumps either, but if those end up in the same rinse water with silver sulfate, the remaining process is anyway the same.
3) hydrochloric acid
HCl will react with silver oxide to create silver chloride, but it is insoluble to water just like silver oxide.
--> does not help getting it off the walls of containers.
Which of these other forum members would other forum members consider?
(or can somebody hint of another method?)
Or would you just forget the silver oxide and try to get the assumed silver cholride out?
I bought a set of lab equipment from a bankrupt company. The lot had many useful pieces for newbie home refiner. (beakers, erlenmeyers, magnetic stirrer, buchner funnels, vacuum flasks, vacuum pump, etc)
When collecting the stuff I had bought, I found two thick walled large (~20 liter) plastic containers labeled silver oxide. I thought that those would be great for waste liquid storage so I picked them up rather than throwing to trash.
The containers did not contain any leftover liquid, but at least one of them contains large clumps of white powder.
The primary reagents used in this lab seemed to be hydrochloric acid, sodium hydroxide and sodium thiosulfate.
My guess is that the white powder could be silver chloride. (somebody rinsed silver oxide container with HCl?)
Both of the containers have black coating on their inside.
I am wondering whether there would be any reasonable way to recover the silver oxide layer from the containers before using them as waste liquid containers. Even though the layer is completely black, it is probably very thin.
I have thought out couple of options:
1) dilute nitric acid.
Nitric will dissolve silver oxide to silver nitrate. The challenge is how to rinse all the container walls without
using large amount of acid. Nitric acid is expensive and expected amount of recovered silver is very small.
I can reuse some amount of leftover nitric acid to refine silver recovered via electrolysis.
Nitric rinse creates NOx gas and due to the size of these containers it might be hard to do this rinse safely.
Nitric won't dissolve any silver chloride clumps from the bottom of containers.
I probably won't be able to get all of the assumed silver chloride out of the containers before the acid rinse.
Nitric acid rinse could contain both: silver nitrate and silver chloride. Need to either separate them by filtering and process separately or convert all to chloride.
2) sulfuric acid
According to many sources, sulfuric acid reacts with silver oxide to create silver sulfate.
Ag2O + H2SO4 -> Ag2SO4 + H2O
This reaction won't create toxic NOx fumes.
Dilute sulfuric acid is available with more reasonable cost as battery acid.
Can somebody enlighten me whether this reaction works with dilute sulfuric acid or does it require concentrated sulfuric acid?
Metallic silver requires concentrated sulfuric acid, but this should be oxide.
Silver sulfate is slightly soluble in warm water.
Would it be possible to recover the silver using small amount of battery acid diluted with warm water?
Silver sulfate can be converted to silver chloride with NaCl or HCl and processed with the assumed silver chloride.
I don't expect to recover pure silver with this method, but I could combine the recovered metallic silver to the silver recovered via electrolysis, which I will refine with nitric acid in the future.
Sulfuric won't dissolve assumed silver chloride clumps either, but if those end up in the same rinse water with silver sulfate, the remaining process is anyway the same.
3) hydrochloric acid
HCl will react with silver oxide to create silver chloride, but it is insoluble to water just like silver oxide.
--> does not help getting it off the walls of containers.
Which of these other forum members would other forum members consider?
(or can somebody hint of another method?)
Or would you just forget the silver oxide and try to get the assumed silver cholride out?