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Author: Subject: Extracting Sodium from Sodium Chlorate
Theoretic
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shocked.gif posted on 31-10-2003 at 06:43


"That Reaction is incorrect

That last reaction does not happen."
What, 2K+2KOH=>2K2O+H2 doesn't happen? :o What the hell? It happens with NaOH when it's electrolysed (that's why the reaction's yield is 15%) , why the hell not with KOH?
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PrimoPyro
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[*] posted on 31-10-2003 at 12:21
It does


All alkalai metals react with their hydroxides to liberate hydrogen.
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Marvin
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[*] posted on 1-11-2003 at 13:49


Anyone who gets a yeild of 15% sodium by electrolysis of molten NaOH is doing something very wrong.

At 5C over the melting point yeilds are over 80% sodium produced based on current. A small amount (I think about 7%) of carbonate also helps.

The reaction between the metal and the hydroxide does happen and can be made to work preperativly at higher temperatures. Observation of this is complicated however, becuase the alkali metals are also soluable in their molten hydroxides to a certain extent.

Electrolysis of NaNO3 also works, but there are a few problems, firstly its an oxidising agent, and sodium is a reducing agent so reactions happen during its formation, secondly the cell generates the highly toxic NO2 gas. I'm not sure how long the electrolysis has to progress before sodium can be collected from it, maybe until a large portion of the nitrate around the cathode has been reduced. Casutic soda is spectacular enough, I think this is best left alone.

[Edited on 1-11-2003 by Marvin]
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PrimoPyro
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[*] posted on 1-11-2003 at 16:11
O2 Liberated


Na2O might not conpletely solvate in Molten Na, but I would bet that it's ionic structure is exposed enough so that in a molten NaOH solution, Na2(+2) and O(-2) can be seperated, liberating O2 at the anode.



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PrimoPyro
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[*] posted on 1-11-2003 at 16:42
Another Process


http://l2.espacenet.com/espacenet/viewer?PN=US6221310&CY...

Found from http://www.ewire.com/display.cfm/Wire_ID/1490

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Marvin
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[*] posted on 2-11-2003 at 17:29


Ross, electrolysis of molten NaCl is not feasable outside an industrial setting. For a start the cells have to be big, or its not possible to lag them well enough to keep the salt molten electrically. Also Sodium at the melting point of salt has a large vapour pressure (about a third of an atmosphere IIRC) so a mistake can be spectacular in a very bad way.
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[*] posted on 29-1-2004 at 15:46
vacum electrolysis


i just read of it on a chem site but it should work.
take an elenmeyer vacum container.
tap the top with a double holed cork.
tight fit two electic poles going all the way till the bottom without touching.
turn on the vacum.
heat the elenmeyr until the sodium chloride that is putted in the bottom melts.
molten sodium chloride conducts electricity.
when the salt is molten turn on the electrycity.
voila. the chlorine gas comes out of the sodium and gets sucked but the vacum.
since there is no oxygen to...the sodium wont oxydise.
once u have the sodium just pot it in a pure hydrocarbon liqid such as pure white gasoline.
so it wont oxidise.
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