Has anyone ever tried to extract sodium from sodium carbonate(wash soda)? I believe it can be done if the carbonate is molten, and then voltage is passed thought it. The sodium should gather on 1 of the electrodes. Questions are:1 How much voltage to apply? 2: Would stainless steel react with the sodium?

melt NaCl 800 C celsius, put 2 Elektoden in the bath and 100Ampere current, at one you get CL2 ( collect the clorgas) the other liquid Na

The fact of the matter is this is not a trivial procedure to do on an improvised scale. The procedure Gammaray outlined is indeed correct, minus just about all the details. You will have to have a molten sodium salt, but I would not advise sodium carbonate. Molten sodium chloride with added calcium chloride will lower the melting point of the mixture making it more energy efficient. The trick is to protect the sodium metal from the liberated chlorine gas as well as from atmospheric oxygen and moisture. The sodium is very reactive at these temperatures.

Industrially sodium metal is made from a device called a Downs cell (look it up). A central carbon anode immersed in the liquid sodium chloride liberates chlorine gas that passes up and out of the cell. The cathode is an iron screen around the perimeter of the cell that keeps the liquid sodium metal away from the chlorine.

I have tried this once to limited effect by melting a small amount of salt in my furnace, followed by running some current through the molten mass with a battery charger. The sodium produced almost immediately started burning, and it melted my copper wires.

I have tried this once to limited effect by melting a small amount of salt in my furnace, followed by running some current through the molten mass with a battery charger. The sodium produced almost immediately started burning, and it melted my copper wires.

I remember some folks in SM tried this improvised method and attained quite a success by using a loop shaped electrode wire to scoop out the formed sodium in small portions into oil or something like that.

However, as you mention it's a very reactive metal and even humidity in air shall make the reaction a hell.

Instead of Sodium Chloride you may use Sodium Nitrate with a melting point of 307º C.
I tryed... but with 6 V and 1 A :S... but I get some sparks :D, hehehe

Cindor, do you have a source which states that sodium nitrate can be electrolysed to sodium?

I would think that it would release NOx gasses (NO2, NO) or oxygen which would cause it to form an oxide Na2O and/or a nitrite NaNO2.

If it is possible its still a great risk, as "Sodium Nitrate decomposes explosively when heated > 538C (1000F)." source: http://www.skylighter.com/msds/SODIUM%20NITRATE%20MSDS.htm

The best and safest way to produce sodium metal is to make what I call a SodaBomb. It looks like a pipe bomb but is used to produce Na instead.

A steel pipe that is threaded on both ends, ~2in. dia x ~12in. long with matching end caps is needed. It is essential to remove whatever coating there is (most likely zinc) so that only the iron contacts the molten Na.

The top cap needs to have steel or other suitable tubing welded to a hole in the cap, it needs to be ~12in. long so the heat wont affect the vacuum tubing. Next a hole is drilled for the graphite anode which needs to be long enough to reach well into the molten NaCl sol. Then attach a wire to the steel tube as the Steel tubing itself will be the cathode.

Now the Bottom cap is attached and the apparatus is filled to within 1" from the top with NaCl and a suitable heat source applied. When the NaCl is thouroghly liquid carefully attach the top cap and apply vacuum to the reaction vessel (an aspirator is best). then apply the correct DC current (you need to work this out for yourself).

When the reaction is done let the vessel cool down with vacuum stil applied and when cool submerge the entire vessel in a nonreactive fluid, (i.e. mineral oil, kerosene etc.) Then you can remove the end caps and cut the Na out or if possible heat the oil sol. slightly to melt out the Na metal.

All this is from memory if I remember anything else I'll reply

At 307º C there's no decomposition, Soum Nitrate is decomposed at 380ºC... far away from 538ºC.

And like I said before I tryed, but with a low A - V... anywhay I get some sparks.

What about the method that that I read about in an old chemistry book (1925),on making reduced metalic pottasium,mix pottasium carbonate with charcoal heat to avery high temperature the potasium is reduced and distills over and is collected under oil,as it is a gas at that temperature.I know it does not seem right that carbon would reduce pottasium but that is what it says

Cindor, by putting the explosive decomposition point "> 538C" I was saying that it would be dangerous if the temp accidentally reached that high.

DMSOnMyVeins, your method would seem to work but wouldn’t the vacuum also pull out quite a bit of sodium vapour before the reaction was complete?

Maybe have a spiralling condensing tube kept at above 100ºC so the condensed liquid sodium would run back into your SodaBomb and still remove the chlorine.

After time you would probably get salt build up from the reaction of sodium and chlorine, or would this react in the pipe before it could get that far sending a sodium chloride vapour out the exhaust?

DMSOnMyVeins:
It looks like the entire vessel is the cathode, if the steel tubing is welded to the top cap.

What do you use to insulate the graphite anode from the vessel, presuming the whole thing is at or near 800 degrees C?

Apart from cost of electrolyte, how about using NaOH instead of NaCl? Its melting point is substantially lower, and we don't have to worry about chlorine gas.

I've performed an experiment similar to the one described above by megalomania, though I used NaOH, an iron crucible (anode), and a steel wire with a loop (cathode). Periodically lifting the cathode, with its small blob of molten Na, then dunking it into a jar of mineral oil, I was able to get a few mg of Na. Not enough to be useful - it was more of a "proof of concept" experiment on a boring day.

The top cap needs to have steel or other suitable tubing welded to a hole in the cap, it needs to be ~12in. long so the heat wont affect the vacuum tubing. Next a hole is drilled for the graphite anode which needs to be long enough to reach well into the molten NaCl sol. Then attach a wire to the steel tube as the Steel tubing itself will be the cathode.


Without insulation between the graphit electrode and pipe, the DC power, IMO, shall short. How do you insulate graphite anode from the steel pipe? Can you elaborate on this? Regards.

When designing a similar setup for magnesium metal production I settled on using a plaster or concrete cap to separate the electrode. An extra large hole is drilled out of the pipe cap and a piece of cardboard with a hole in the center is glued to the bottom of the cap. The electrode fits into the center hole, and the cement is filled in around it and allowed to dry. The cardboard should be removed unless you are unconcerned with it burning away.

It may not be necessary for a vacuum source, at least such is the case for magnesium, so sodium might be different. The chlorine gas produces a positive pressure, and it can be directed out through a water trap. The water trap is a closed jar of water that the exit gas is bubbled into. There should also be an empty overflow jar before the water trap to prevent any water from being sucked back into the heated container (potential disaster avoided there). The purpose of the trap is to exclude air. This is similar to excluding air from fermentation of sugar to get alcohol.

The one good reason I see to using vacuum is to keep the quantity of chlorine gas to a bare minimum thus avoiding a competing reaction with sodium metal and chlorine gas reforming salt. I would still recommend using a trap in this circumstance, perhaps an oil based one to condense any fumes of sodium that pass over, but more importantly to keep sodium vapors out of your vacuum equipment. Even if you use an aspirator the possibility of a leak exists, and you do not want water entering an 800 degree environment, or any sealed container at any temperature above waters boiling point.

The only problem with using molten sodium hydroxide is that it will play hell with your steel container. The corrosion will be excessive, but at least such pipes are cheap enough if manufacture is not on your agenda.

The only problem with using molten sodium hydroxide is that it will play hell with your steel container. The corrosion will be excessive, but at least such pipes are cheap enough if manufacture is not on your agenda.

Would molten sodium hydroxide corrode stainless steel, I imagine that the corrosion would be excessively less than on normal steel pipes.

Take a look at this. It looks like this sodium was produced in a "sodabomb" and this ebay seller is trying to sell this stuff.

http://cgi.ebay.com/Sodium-metal-6lb-ingots-salt-lab-chemicals_W0QQitemZ170035576790QQihZ007QQcategoryZ 104233QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

If NaOH is heated a little more than ts melting temerature sodium formed by electrolysis will dissolve in NaOH and I belive it is impossible to sepearte them (perhaps it could be done by distilling of the sodium if it's boiling point is lower than the boiling point of NaOH).

That ebay item is a classical ingot as bought from a sodium manufacturer, and it is not made with your "soda bomb" thing. If it would be, it would have look different.