# Silver nitrate mixed with NaOH



## hrushi (Feb 23, 2009)

In my refining unit i have a scrubber underneath it i have an NaOH tank for nullifying NO2 fumes which come out from reactor. In that some AgNO3 is being added due to powerful blower.

Now i dont know how to recover silver from it. The solution contains NaOH+H20+AgNO3.


Hrushi


----------



## peter i (Feb 23, 2009)

It has probably precipitated as silver oxide.

Decant, wash and dry, then heat to decompose to metallic silver.






http://en.wikipedia.org/wiki/Silver_oxide


----------



## goldsilverpro (Feb 23, 2009)

Looks like I'm a day late and a dollar short on this reply.

I would assume that the silver would be in the form of solid dark brown silver oxide. If so, just filter it out or let it settle, siphon, rinse, settle, siphon, rinse...... The silver oxide will start decomposing to silver metal at 320F and it will go fast at 500F.

In my references, it don't say that silver oxide is dissolved by excess NaOH. I seem to have heard that someone say that it did, however. If, on the rare chance it does, I would dilute or neutralize the NaOH a little with dilute H2SO4 - keep it definitely alkaline, though. The Ag2O should precipitate at some point. Experiment with small samples.


----------



## Lou (Feb 23, 2009)

It does dissolve in a gross excess of base.


----------

