Conversion of AgCl via NaOH and Karo Question

[samuel-a]

Thanks Lou, seems like i had to factor in the H2 generation as well.
If that's the case, this might work for me.

You're getting borohydride for that cheap? I'll be glad to buy some of it--Dow has been ripping me off!


I don't think it'll cost that much.

Yes, that is the price i can get it for. But there is a catch, as it means i need to join in a "pool purchase" (if you will), where the material is imported in bulk by several entities and the minimum buy-in is for 100Kg.
Don't know what in the world i'll do with so much material...

 

[Lou]

If it's lab grade, probably about $200/kg.

 

[samuel-a]

If it's lab grade, probably about $200/kg.

I suppose it might.
Though i was referring to reagent grade material.

 

[au-artifax]

I think this mystery will probably continue at least unless we learn more about the complicated organic chemistry.

I believe samuel-a is correct on the reaction of silver chloride forming an silver oxide in solution as an intermediate reaction, and here in our formula with karo syrup we see we also have excess sodium hydroxide (1 mole excess) (after Ag2O forms) for the sugar to react with the excess sodium hydroxide in solution to react with the silver I oxide that was formed.

2AgCl + 2NaOH --> Ag2O + 2NaCl +H2O


In our formula for silver chloride reduction using sodium hydroxide and glucose (karo syrup):
2AgCl +3NaOH + C6H12O6 --> 2Ag + NaC6H11O7 +2NaCl + H2O

In looking at the glucose reduction we see the glucose gives up an H in its chain and gains an O in its place.
I assume with the reaction of that extra mole of NaOH and the Ag2O.

I could not draw the chain here, but if you look at the pictures here (wiki link below),for glucose, then for sodium gluconate we see this.
We Know the silver gives up it chloride, and sodium ends up with it as salt water, we also assume the glucose sugar forms sodium gluconate in solution.

http://en.wikipedia.org/wiki/Glucose
http://en.wikipedia.org/wiki/Sodium_gluconate

 

[ashapura refinery]

Hello Everybody

I have gone through the posts on this topic and I tried the procedures mentioned here.

The steps I did for the silver refining:

1. Mixed Salt (With Iodine), sugar and caustic soda together
2. added the above mentioned mixture to the Silver Nitrate Solution - the metal started settling down
3. filtered the solution
4. washed the solution with HCL

The outcome looks something like this -

Does this look correct or is there something wrong in this? And since I have used salt with iodine - will it create problems?

 

[4metals]

You seem to have combined all of the steps into one. It doesn't work like that.

First add salt or hydrochloric acid to your silver nitrate, non iodide salt will prevent the formation of silver iodide.

Filter the silver chloride from the solution and rinse it well.

Now slurry the silver chloride to make it a thin paste and add the sodium hydroxide to the slurry. You will see the solution turn dark. Mix it well to eliminate any small white specs which are unreacted silver chloride. You now have silver oxide.

Then you add your corn syrup to reduce the silver oxide to metallic silver.

The down side to this method is it takes a lot of rinse water to get the purity high.

 

[ashapura refinery]

You seem to have combined all of the steps into one. It doesn't work like that.

First add salt or hydrochloric acid to your silver nitrate, non iodide salt will prevent the formation of silver iodide.

Filter the silver chloride from the solution and rinse it well.

Now slurry the silver chloride to make it a thin paste and add the sodium hydroxide to the slurry. You will see the solution turn dark. Mix it well to eliminate any small white specs which are unreacted silver chloride. You now have silver oxide.

Then you add your corn syrup to reduce the silver oxide to metallic silver.

The down side to this method is it takes a lot of rinse water to get the purity high.

Thank you for the reply. I will re-try the method as per the instructions.
Can you explain further what is the difference between corn syrup and sugar syrup? And sugar syrup is made by mixing sugar in water - right?
And right now I am not able to get corn syrup so can I go ahead with Sugar?

 

[Palladium]

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=37&t=14618#p147119

 

[ashapura refinery]

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=37&t=14618#p147119

Thank you for the reference.