Extracting Sodium from Salt

[aj47]

Do any of you know a way in which I could succesfully extract sodium from salt? Obviously displacments out of the question as I cannot get my hands on any highly reactive metals but would electrolysis be succesful. If yes what solvent would be needed as I guess water could not be used due to the formation of NaOH?

 

Realsitically is this possible with my limited apparatus or completely out of the question?

[leidiot]

I searched on google. Most came back with the answer: Melt it down and conduct electrolysis

[aj47]

not sure about melting it, as it has a melting point of 801C which I very much doubt I could get to, or sustain in my house.

 

I think if anything I would need some extremely inert and electrically conductive solvent to dissolve it in but I havn't a clue what or even if any exists.

[RyanJ]

not sure about melting it' date=' as it has a melting point of 801C which I very much doubt I could get to, or sustain in my house.

 

I think if anything I would need some extremely inert and electrically conductive solvent to dissolve it in but I havn't a clue what or even if any exists.[/quote']

 

I suppose you could if you reacted it with potassium... you'd get Sodium precipiteated but it would react with the water instantly.

 

I suppose electrolysis would work but your electric bill for melting the salt could cost a fortune

 

Cheers,

 

Ryan Jones

[aj47]

yea thats what I meant by displacement but I can't really get my hands on any potassium.

I think Ive come to my own conclusion that it would be pretty much impossible with out investing in some highly expensive equiment which I cannot afford on my shop assitant salary.

But any of you know if I could easily buy a few grams on the interenet?

[RyanJ]

yea thats what I meant by displacement but I can't really get my hands on any potassium.

I think Ive come to my own conclusion that it would be pretty much impossible with out investing in some highly expensive equiment which I cannot afford on my shop assitant salary.

But any of you know if I could easily buy a few grams on the interenet?

 

Yup, is quite easy too get hold of.

 

http://www.smart-elements.com/index.php?element=Na&arg=show

 

Or just search around E-bay for a while

 

A good description of how they extract Sodium cna be found here:

http://www.webelements.com/webelements/elements/text/Na/key.html

 

Or here:

 

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

 

Cheers,

 

Ryan Jones

[aj47]

ah interesting, thanks for the links

[RyanJ]

ah interesting, thanks for the links

 

No problem, it seems that due to the reactivity of Sodium compared with most other elements its hard to extract without Electrolysis to do so. infact it seems its cheaper to just but the stuff

 

Cheers,

 

Ryan Jones

[aj47]

Hmm, yea going to buy some anyway but would have been fun to extract it myself, as i'm in a experimenting kinda mood.

 

Ah well.

[bereal511]

Well, if anything, you could just electrolyse the salt in a solution to yield NaOH and Cl2, then boil down the solution to obtain solid NaOH, melt it, then electrolyse that. Its melting point is easier to reach, about 323 degrees Celcius.

[aj47]

good point, but I can't think of any way I could realistically do that in my own house, any suggestions?

[woelen]

Forget about making sodium in your own house. You are asking for deep troubles and accidents. It simply is too dangerous, unless you have some really good equipment and a LOT of experience with experimenting.

 

I myself am doing quite some chemistry experiments at home, but extracting sodium from NaOH and/or NaCl I do not attempt. I appreciate my health and my life too much to spoil it with such an experiment .

[Ilja]

you could extract it by an electrolysis but u will need a special kathode , which is made out of quicksilver , because of the electrochemical series.

[[w00t]]

Wouldnt as soon as you optain the sodium metal it would ignite because of the heat required to melt the NaCl is well above the ignition temp for sodium metal?

[RyanJ]

'']Wouldnt as soon as you optain the sodium metal it would ignite because of the heat required to melt the NaCl is well above the ignition temp for sodium metal?

 

Yup, it would probably ignite, you'd probably have tp have it doen in an inert atmosphere to stop it reacting with the atmospheric compounds... At those temperatures it would react with just baout all the compounds and molecules in the atmosphere....

 

Cheers,

 

Ryan Jones

[YT2095]

you could extract it by an electrolysis but u will need a special kathode , which is made out of quicksilver , because of the electrochemical series.

 

agreed, making sodium amalgam is the only reasonable method for a home chemist.

from there you need to displace the sodium with a more reactive metal such as K, Li, Ca...

having a bottle of Argon gas is also a good idea

[TATER]

would it be possible to dissolve a large quantity of salt into water and then electrolyze it?

[woelen]

Yes, but it won't give you sodium metal.

[TATER]

What would it give you?

[John Cuthber]

Initially, NaOH at the cathode and chlorine at the anode. the NaOH diffuses across and then reacts with the Cl2 to give NaClO.

This can also get oxidised to NaClO3 etc. Of course, all this presumes that your electrodes are inert.

Overall you get quite a mixture, but no sodium.

You can make sodium by electrolysisng molten NaOH but I don't recommend doing that at home and the yield isn't very impressive because the stuff tends to catch fire as soon as you make it.

[woelen]

John, you forget one important thing. H2 is formed at the cathode. For the rest, I agree.

 

Chlorate also can be formed due to disproportionation of hypochlorite. It is the usual mode of operation of a chlorate cell.

[tellerulam]

Why is NaOH not Na formed? When salt is dissolved in water NaOH isn't produced is it? From my understanding Na bonds to the electron lobes on oxygen and the hydrogens stay too.

[woelen]

In fact, it is not really true that NaOH is formed. We are talking about ionic compounds, and it is better to say that hydroxide is formed.

 

At the cathode, electrons are 'pushed' into the liquid, and this causes water molecules to be broken down as follows:

 

2H2O + 2e --> H2 + 2OH(-)

 

You see? The source of the hydroxide is the water.

The sodium ions just do nothing, and this is because electrons can easier be passed to water molecules than to sodium ions. If you were working with molten salt, then there is no water, and then the electrons are passed to sodium ions:

 

Na(+) + e --> Na

 

In molten salt, sodium ions accept electrons easiest. Chloride ions cannot accept another electron.

 

In general, when electrolysing things, electrons are given off at the cathode and are consumed at the anode. Both at the cathode and the anode, you have to look at what is present over there and what of all those different things can easiest accept (or give away) electrons.

 

You have to consider

1) The solvent (if any)

2) The ions

3) The electrode material itself

 

In the case of electrolysis of NaCl in water with copper electrodes, you have available near the cathode:

Cu metal

Na(+) ions

Cl(-) ions

water

 

Of these 4 things, water can accept electrons easiest.

 

At the anode, when using a copper anode, the same four things are present. Now the question is, which compound can easiest give off electrons (the anode absorbs electrons). Now this is the copper metal. So, the copper anode will dissolve and erode.

 

Now suppose we are electrolysing molten sodium hydroxide with copper cathode and platinum anode.

 

At the cathode we have:

 

Na(+)

OH(-)

Cu metal

 

Of these, the Na(+) ions easiest accept electrons. So, sodium metal is formed.

 

At the anode we have

Na(+)

OH(-)

Pt

 

Of these, OH(-) easiest gives off electrons, forming OH. This quickly reacts, giving water and oxygen. So, at the anode you will see oxygen bubbling and also water bubbling (due to the high temperature).

[tellerulam]

Thanks woelen. This one post taught me more about electrolysis than my AP Chemistry teacher managed to teach me in almost one and a half a semester.

[weknowthewor]

using the process of electrolysis, if u use solution of patassium sulphate, sodium gets collected at -ve electrode as clorine reacts with patassium 2 form KCL