Out of sodium hydroxide!

Gold Refining Forum

Help Support Gold Refining Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Rreyes097

Well-known member
Supporting Member
Joined
Mar 30, 2016
Messages
661
Location
Northern California
So I've got a little bit of silver chloride but I'm all out of sodium hydroxide. Does anyone know of another way to get my silver chloride to silver oxide or metal silver. Because I don't want to buy a whole another bottle of sorry I'm hydroxide for a gram or two of silver probably eventually get it but I don't want to get it right now anybody's tips would be much appreciated thank you!
 
If you have only 1 g or 2 of silver chloride, you better use light to convert it to silver.
Silver chloride slowly change color to grey...it change itself to silver...but it's very slow.
 
Just buy that kilo of lye and you will be fine. Unclogg the drains in your home, clean wife´s baking oven, treat your waste solutions... So many applications for sodium hydroxide :D
Agitation of AgCl with aluminium or iron in dilute acid slowly convert the chloride to metallic silver.
If it is only a small quantity, you can also dissolve it in concentrated ammonia and precipitate it using borohydride or other suitable reducing agent. Just don´t store dissolved silver-NH3 solution - become explosive over time, forming silver nitride.
 
Wow thanks for all the input guys. But I found drain cleaner that had sodium hydroxide as well as potassium nitrate and it seemed to do the trick we'll see any thing you guys see wrong with that yet? I'm not making a bomb am i?
 
or use baking soda. First heat up the baking soda until it stops offgassing. You can tell it is done when the powder quits boiling. You now have sodium carbonate and can melt the silver chloride with the sodium carbonate and obtain silver metal.
 
Put sodium bicarbonate in a flat pan. Place in kitchen oven for an hour@ 400 F. Remove and let cool. Place in air tight container for use later on. Pretty close to sodium carbonate for practical purposes. Hard to tell in field if all CO2 is removed.Any body out there know a good field test or reaction indication when reduced to pure carbonate?
 
A guide to the temperature/reaction rate would be useful if anybody knows.

I took some data a few months ago on converting sodium bicarbonate to sodium carbonate with heat:
At 0 hours, net mass 100 grams (0% converted)
At 1 hour, net mass 80 grams (54% converted)
At 2 hours, net mass 67 grams (90% converted)
At 3 hours, net mass 63.4 grams (99% converted)
This was baked at about 300F on an open electric hotplate in a shallow aluminum foil dish, sodium bicarbonate powder layer 1-2cm deep, sample surface temperature 105-110C, loosely covered to keep heat in but let CO2 and H2O out. The powder looks identical to me before and after conversion to sodium carbonate, just label your containers. Deeper layers of powder don't convert well, with the CO2 and H2O driven off the bottom layers cementing the top layers together. Eventually it all heats up and converts, but it takes a while. Higher temperatures would probably convert faster, although the CO2 and H2O from flame might slow down the conversion (which is why I used electric).

An open dish of sodium carbonate very slowly converts back to sodium bicarbonate, with a half-life in air of several weeks in my tests (dry cool winter indoor temperatures).

If you're dumping it in a melting dish as a flux, the flame for melting will probably rapidly do the work of converting sodium bicarbonate to sodium carbonate anyway!
 
Last edited:
Gravimetric technique is very good for this.
Just calculate how much water and CO2 should escape, and bake in the oven - conveniently as you describe. Do not enclose the space, as significant gas volume will be emitted.
 
I took some data a few months ago on converting sodium bicarbonate to sodium carbonate with heat:
At 0 hours, net mass 100 grams (0% converted)
At 1 hour, net mass 80 grams (54% converted)
At 2 hours, net mass 67 grams (90% converted)
At 3 hours, net mass 63.4 grams (99% converted)
This was baked at about 300F on an open electric hotplate in a shallow aluminum foil dish, sodium bicarbonate powder layer 1-2cm deep, sample surface temperature 105-110C, loosely covered to keep heat in but let CO2 and H2O out. The powder looks identical to me before and after conversion to sodium carbonate, just label your containers. Deeper layers of powder don't convert well, with the CO2 and H2O driven off the bottom layers cementing the top layers together. Eventually it all heats up and converts, but it takes a while. Higher temperatures would probably convert faster, although the CO2 and H2O from flame might slow down the conversion (which is why I used electric).

An open dish of sodium carbonate very slowly converts back to sodium bicarbonate, with a half-life in air of several weeks in my tests (dry cool winter indoor temperatures).

If you're dumping it in a melting dish as a flux, the flame for melting will probably rapidly do the work of converting sodium bicarbonate to sodium carbonate anyway!
Thanks for the info O.
 
Back
Top