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ybk

Sodium hydroxide

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Hey...

 

i'm new to these forums so be nice :)

 

I have a question, and whoever can answer WILL get a cookie... ;)

 

anywayz, how can you get the sodium out of the sodium hydroxide?

All i need from the solution is the sodium....

 

if you can answer me on that one, it'd be greatly appreciated :)

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What you have to do is get yourself a dry box. A dry box is a completely sealed box with which all of the air inside can be purged out and replaced with another gas. Take a good amount of the dry sodium hydroxide and put it inside the dry box. Close all the doors and pump the air out of the drybox. When the vaccuum is made, start backfilling with argon gas. This way you'll have a very nice argon atmosphere in there. Now take the sodium hydroxide in this dry box and melt it by heating it up. (You should have the heating apparatus already in there). Make sure the sodium hydroxide is completely molten.

 

With the NaOH in a liquid form, you can now do electrolysis. :D Take a voltage source and put the positive and negative electrodes into the molten NaOH. (Make sure the electrodes won't melt and that they won't react with the INCREDIBLY caustic molten NaOH). With the electrodes in there, turn on your voltage source. You will soon see molten sodium metal form at one electrode, and water vapor and oxygen forming at the other electrode. YOU MUST keep the oxygen and water vapor away from your molten sodium. If you don't, a small explosion will occur as the molten sodium reacts with the oxygen and water. So you should probably isolate that positive electrode (Where the oxygen and water will form) and have a dessicant material there to absorb the water and a way to outlet the oxygen out of the box.

 

Once you have this setup going for quite a while, you'll be able to obtain a bunch of sodium metal. Then you just need to let everything cool off so that it will solidify and find a way to store your metal.

 

Now seriously speaking, it's not that easy to do. I assume that you want the sodium metal because you want to throw it into some water. Now why do you want to throw it into some water? Because it will react rapidly, correct? So if it reacts rapidly with water, do you think you'd be able to get sodium metal out of an aqueous solution of a sodium salt? ;)

 

The only way to generate sodium metal is to electrolyze a molten sodium salt. If you don't do it in an inert atmosphere devoid of water and oxygen, the liquid metal that forms will quickly react and you won't be able to make quantities much larger than a gram or so total. (If everything works out alright).

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anywayz' date=' how can you get the sodium out of the sodium hydroxide?

All i need from the solution is the sodium....

[/quote']

Solution! :eek:

You cannot.

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As jdurg already explained to you, making sodium metal at a small/home scale is incredibly difficult. Forget about it. The average hobbyist will NOT be able to make sodium metal at home. Attempting to do so probably will result in severe injury and fire if you do not know exactly what you are doing.

 

Obtaining sodium is not easy at all for the general public and there are good reasons for that ;).

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As jdurg already explained to you' date=' making sodium metal at a small/home scale is incredibly difficult. Forget about it. The average hobbyist will NOT be able to make sodium metal at home. Attempting to do so probably will result in severe injury and fire if you do not know exactly what you are doing.

 

Obtaining sodium is not easy at all for the general public and there are good reasons for that ;).[/quote']

 

The damn metal is so active and hygroscopic that it will literally suck oxygen from the surrounding alternating with water vapour until it ends up being NaOH in solution and the heat liberated can start a fire easily if it came in contact with any inflammable material. We used to handle it very carefully in Pyrex and submerged in inert oil to prevent contact with air. I heard that the major consumer industry is that of double laminated glass sections with semi-vacuum (law pressure) in the middle to insulate sound and heat.

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very often it comes in 12.5 and 25g alu canisters to be thrown into furnaces for some sort of metal purification process, that`s where I got all mine from :)

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The only way to generate sodium metal is to electrolyze a molten sodium salt. If you don't do it in an inert atmosphere devoid of water and oxygen' date=' the liquid metal that forms will quickly react and you won't be able to make quantities much larger than a gram or so total. (If everything works out alright).[/quote']

 

ahhh... can that be done in a normal lab?

 

or will i just blow myself up... :D:eek:

 

hehe, hands cookie to *closes eyes* *random pick* jdurg!!

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It can be done in a typical lab, but only with the right equipment and a lot of materials (As explained in my lengthy post). The amount of time and effort required to do the electrolysis is simply not worth it when you can just go and buy some sodium metal dirt cheap from a supplier. It is possible to generate small quantities of sodium metal without the use of a dry box, but you'd still have to use a LOT of heat to keep the NaOH molten and working with molten NaOH is a very dangerous thing to do. Also, because of the heat the sodium that is made will be in the form of little liquid droplets of highly reactive metal. If any of that water vapor that is formed at the positive electrode comes in contact with the molten sodium metal, you're going to wind up with an explosion that sends liquid Na and liquid NaOH all over the area. If that gets on you, you're not going to be happy. Besides, even if you were able to make the sodium without an explosion happening, the stuff you get will be HEAVILY oxidized and you're not going to be happy with the product. It's cheaper, easier, and safer to just go out and buy some.

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I`m still surprised that no one used the NaOH Hg electolysis to make the amalgam and just displace it with Lithium.

 

so simple an 8 year old could do it!

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Generally speaking, if someone is looking to make sodium metal, they don't have lithium metal hanging around. (And the stuff you pull from a battery is too heavily corroded to be of any use). :D

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the stuff from batterys doersnt have to be corroded at all. i extracted alot of lithium from e2 lithium batteries by energizer. if the batterys are new, u can take it out pretty easily and in very pure form and in pretty large amounts. theres a secret method to doing it tho....

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Well akcapr Its not good to keep secrets do enlighten us?

 

~Scott

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okay (wen i get to doing this again ill put it on my site), anyways, you take a AA lithium battery. And you cut off the bottom cap of the battery. you then take a flame (blowtorch would be best) and strongly heat the back side of the battery away from the openeing. you hav to be careful not to touch the lithium with the flame since it will ignite. ok, so you heat it, then the lithum will melt and ooze out. take some pliers and squeeze the battery like a toothpaste stick- the molten lithium will pour out and then you can collect it (you could drip it directly into oil probly). wen in the molten state its very pure, the rate of oxidation after that depends on how fast you put it in oil or watver.

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cool method.

 

When i did it i cut the whole battery in half and pulled the Li out.

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well, in my childhood i tryied that with the only porpuse of making it explode into water.

 

after some 3 years, i stopped that and started using nitroglicerin.

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i would smile upon one who could make sodium at their home ive been trying to do it for a while. its very hard and fairly dangerous ive been trying to a use lithium displacement reaction i read soemwhere to isolate the sodium..... if anyones got any info on this id love it. by the way if you do end up isolateing sodium... can i haeva sample?

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LOL secret method... u cut open the bateries and unravel the strip of lithium and the black stuff of which i forgot the name and dunk it in oil... i used mineral spirits for the oil but diseal fuel works. use lithium photo batteries... just find one that says "lithiun pile" on it somewhere thats the kind you want

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The thing is, it's not all that economically viable to try and get the lithium in that manner. Those batteries are not exactly inexpensive and in order to get a good deal of lithium you have to spend a decent amount of money. When making small amounts of ANY of the alkali metals, it's really not cost effective. (And by small amounts I mean less than 1 kg quantities. Chemical manufacturers are able to do it because they make massive quantities and the price per gram for them is dirt cheap due to the bulk quantities).

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o yah i get all my batteries for free just use dead ones. they still have all their lithium. compared to a new one and battery stores will happily give you a few hundred for free. they are the ones that have to dump it. reduces the load

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I`m still surprised that no one used the NaOH Hg electolysis to make the amalgam and just displace it with Lithium.

 

so simple an 8 year old could do it!

 

Can you describe the procedure please, thanks that will be allot of help! ;)

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here`s some data on the Amalgam : http://en.wikipedia.org/wiki/Sodium_amalgam and one of the ways it`s made.

 

from there you can use either potassium or Lithium metal to displace the Sodium metal :)

 

it`s a realy powerful reducer in fact: "This is a major modern use of mercury, and one for which there are few alternatives. Aluminium was first isolated by Hans Oersted in Denmark in 1825, who used potassium amalgam to displace it from aluminium oxide."

(taken from: http://www.du.edu/~jcalvert/phys/mercury.htm).

 

hope that helps :)

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