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Author: Subject: unconventional sodium
Cyrus
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[*] posted on 16-6-2004 at 09:42


Quote:
Originally posted by Tacho
There is no way the sodium will deposit nicely in the steel wool. The high temperature makes it vaporize. Even the condensed sodium is quite dirty. I couldn’t even melt it into a single blob.


Ok, I was exaggerating about my expectations for nice shiny globs of sodium- dirty stuff is fine for now. And yes, the Na will be a vapor when it is produced- but some should deposit on the steel wool if it is cold enough, clean or not.

Edit, why won't the sodium be pure- if its done in an inert gas, assume, and the only products are MgO, H2, H2O and Na, what is the impurity? NaOH? MgO? NaH? NaOH can be removed, but I don't know about the others-could the sodium be distilled to purify, even if it won't melt?

Also, I tried magnesium turnings and sodium hydroxide under molten candle wax today, I heated the candle wax till boiling, there was vigorous bubbling of hydrogen, the Mg turned black, the wax caught fire- when the torch was placed straight at it, the flames billowed about 1m high.:D:D:D. When placed under water, nothing happened. (the reactants were covered in solidified wax) If a decent way of extracting the Na from the wax and the MgO/ Mg(OH)2 is found , this might be a simple and promising method.

Halfway throught the reaction, I discovered that a prill of NaOH had located themselves on my arm, and were busy making Cyrus-soap... :mad: I was most annoyed because I had to stop watching the reaction and wash myself.


[Edited on 18-6-2004 by Cyrus]

[Edited on 18-6-2004 by Cyrus]




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[*] posted on 22-6-2004 at 14:31
A hair raising experience


Today, I tried to make sodium. Once again.

I used the copper test tube setup previously described, but I used lots of teflon tape to keep the joints secure, and the outlet of the setup went diagonaly into a food-can with about 2 cm of mineral spirits in the bottom.

I used 1g of NaOH and 0.6 g of Mg, this mixture was placed into the bottom of the test tube. I was doing this quick and dirty, so I didn't even bother using a clamp to hold the setup in place, I just held the food can with my left hand, and held the torch in my right. Bad move.

Upon heating, some bubbles peacefully drifted out of the copper setup for a minute or two. I began thinking, either this reaction is very slow, or it takes a while to get started. Then

Whumphh!

I remember
-1- a very bright flash and a loud noise
-2-a large wave of heat
-3-a hot and sticky sensation
-4-the apparatus decomposing into several flaming objects,
-5-my goggles dislocating themselves from my head somehow

At this point I decided it would be best to leave the area, and then I noticed that the wave of heat was COMING FROM MY HEAD! :mad::mad::mad:

I ran into my garage looking for a bucket filled with ice-cold water (there are no buckets of water in my garage, ever) while beating down the flames on my head with my hands.

Finally, I put the flames out.

Aftermath
-the still flaming apparati were burning holes in the grass
-the propane burner was still on, only heating concrete, though
-mineral spirits were all over me, the concrete, and my goggles
-the goggles were on fire
-All hope of sodium was lost (the most important) :D
-Oh yes, and the last 0.5 cm of almost every hair on my head had turned white and crinkled, including my eyebrows and lashes, which were behind the safety goggles!:o One of my ears was burnt.
My hair sticking up in fused masses at every angle, I truly looked the mad scientist.:D

I smelled like burnt hair and mineral spirits. Pleasant.

Things I have learned
-BromicAcid has good reason to use those beefy iron pipes-which I will use from now on.

-Do NOT stand within 3m of such reaction.

-Teflon tape will not hold very well when using magnesium- it works with Al.

-Water is very good to have at hand.

All in all, a very exiting day. I think I'll take a little siesta from reactions for a day or two though. :)

Nevertheless, SODIUM SHALL BE MINE!




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[*] posted on 22-6-2004 at 19:01


Jeeze, atleast you were using small amounts.

Have you ever tried this before with magnesium as your reducing agent with out a coating like you had in your previous post? It was mentioned in this thread that it can be explosive
By chemoleo:
Quote:
instead of Al I used 200 mesh magnesium (so no grains/filings like BromicAcid once did). As soon as I put the propane torch onto the mix (from below, so the mix never contacted the open flame),it ignited, making a massive flash of light, and spewing molten white glowing bits everywhere!!


And in one of my quotes:
Quote:
"The hydroxides or carbonates of the alkalimetals -- excepting cesium -- are reduced by heating a mixture of one mol. of the carbonate with three gram -- atoms of magnesium.... The reacton with lithium proceeds with explosive violence.... with potassium and rubidium the reaction proceeds quickly.."


So where you expecting this? Magnesium oxide can be added to help moderate the reaction.

Best of luck with future experiments, and those 'big beefy pipes' really do make you feel safer ;)

[Edited on 6/23/2004 by BromicAcid]




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[*] posted on 22-6-2004 at 20:12


No, I was not being cautious enough.

But I was using large Mg turnings, not fine powder, (as Tacho advised IIRC) and about 2 g total materials, so I just expected the reaction to go "nice and quickly",
not explode like a small bomb.:( I was not expecting anything like what happened, of course.

Now that I have done it, it is not a reaction I would say proceeded "nice and quickly"
:D

Don't worry about my health, the ear is doing ok, and all of the crisped hair seems to have fallen off, thankfully.

Bromic acid, with your large steel pipes, to prevent suckback, instead of using a one way valve, why not make the level of water such that whenever it gets sucked back, the water level lowers enough to let air through. This has probably been said somewhere before, but oh well.

Be warned, I have just caught the phosphorus bug.
:D

[Edited on 23-6-2004 by Cyrus]

[Edited on 23-6-2004 by Cyrus]




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[*] posted on 23-6-2004 at 04:39


I’m very sorry about what happened to you Cyrus! I hope you are OK. You were very wise to test the reaction with little reactants!

Thank you for describing what happened, thus helping other people NOT to do the same mistakes.

I’ll start a list of things that should be remembered:

Stay many meters away from any thermite reaction;

Never do thermites in closed tubes or pipes, even it it has a small vent. Any unexpected explosion should have space to release its energy without shards or shrapnel;

Test the reaction first with little reactants;

Magnesium in thermites is not a good idea;


Anybody?
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[*] posted on 23-6-2004 at 11:36


Let me add to this:

Heat your reaction REMOTELY, not with the burner in one hand, and the setup in the other!!!!

NEVER EVER use flammable liquids together with an open flame!!! Particularly in the combination burner/flame/thermite/mineral spirits!!! (unbelievable really - I got hurt badly with much less stupidity!)


By the sound of it, you really have to get your act together, or next time you will get injured badly. Trust me I am speaking from experience. Recklessness punishes you faster and harder than you can blink your eye.
It's not a cool story anymore once you lie in hospital with 2nd/3rd degree burns, and a few shards in your abdomen.




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[*] posted on 23-6-2004 at 15:39


Thanks for the good advice - the act is now together, for all such future reactions I'll use some clamps, thick iron pipes, a "blast shield" made out of spare sheetrock, and more common sense. And I'll be farther away.

I'm glad this happened because it was a good warning.

Tacho, the apparatus was not a closed tube, it had an opening, but my description may have been confusing.

Chemoleo, what did you do to yourself:(, and also, if I want to make/distill sodium, I think flammable liquids must be used to bubble the vapors through, any suggestions?




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[*] posted on 23-6-2004 at 16:19


To be honest, I don't think you have much chance of condensing Na vapours in those oils. I played around a little with potassium in inert oils, and the metal tends to separate into thousands of tiny globules rather than condensing into a coherent one. With K/Na - vapours.... I'd rather think you will get an emulsion... if that. Sodium gas... sounds good in theory... but again, I doubt very much it occurs for real, with the thermite reaction. Remember I tried it, several ways. Distillation in an inert atmosphere is the only way I can see this to work (with massive heat, well above the boiling point of Na), if that. Even then, I do think most of the thermite products are aluminates/aluminium hydrides, despite stoichiometric equations. As I said above once, I tried heating the thermite product in petroleum, for several hours, to release the Na (which should melt) but it didn't work at all.
If I was you I wouldnt pursue it because I'd doubt it would work, and I'd be too worried about saftey (open flame and mineral spirits).

I think it's very interesting what Tacho mentioned about reaction with alcohols (i.e. ethanol) - he described evolution of gas (H2?), where the product still reacted violently with water.
May I ask whether it was absolute alcohol??

If yes, it sounds like a very decent method for preparing alcoholates, I wish I had tried it.

Does anyone have some experience in purifying/playing with alcoholates?

For instance, Tacho, once you react your thermite product with alcohol, what did you do with it? Did you try to react it with something, to confirm you had truly some NaOC2H5??? Please elaborate!

PS On the note of my past incidents... I will elaborate on taht one day... in the 'most serious injury' thread. Never found the guts to do so so far :P but dont worry I am not disfigured or anything... you cant see it.... although it's left me with a healthy permanent scar of being cautious. And you, Cyrus, sound just like me when I was 16... and I paid a dear price for that. Be warned, seriously!! I didnt get such a warning (I didnt know of the internet then), while you DO! Be careful, man! no more thermites with Bunsens igniting it by hand! I mean it! A tiny bit of neglect can cause you more harm than you can imagine.

[Edited on 24-6-2004 by chemoleo]




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[*] posted on 23-6-2004 at 17:20


Interesting, chemoleo, it’s the second time you say you doubt the thermite. Since I claimed to have obtained sodium by it (dirty small nuggets), you put me in a awkward position! Well, who cares! Here is my methoxide experience:

I reacted the condensates that I say are sodium and the residues of the reaction (NaOH+ NaCl+NaCO3+Al, the NaCl makes all the difference, I BET you never done it using NaCl and NaCO3 as I described) with anhydrous methanol, they bubbled and fizzled( I just poured the methanol in the ss cup that held the thermite and added the condensed powdery sodium into it).

After it settled, I poured the methanol in another flask and added water to the ss cup (to wash it). Hell broke loose: bubbling, fizzing and boiling out of the flask.

Then I boiled away most of the methanol and added IPA, to precipitate some NaOH. Some white powder really precipitated. The decanted IPA was very, very alkaline (correct if I am wrong, but IPA dissolves very little NaOH). The reaction I tried that used methoxide failed, but I believe it was not the methoxide fault. I think I got that part right.

I'll be glad to repeat the methoxide thing it in a smaller scale if anyone wants to test an specific theory! Some decent theory please.

[Edited on 24-6-2004 by Tacho]
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[*] posted on 23-6-2004 at 18:44


No no,
this is not about doubting you or anyone, it's about finding out what you tried!
Regarding the Na nuggets - I have doubts simply because I didnt get any. So I am trying to find out why that is so.
I am very intrigued by you methoxide experiment, nonetheless. Can anyone imagine a simpler DIY method for preparing it??
I wish there was some way to discern methoxides/alcoholates from other products (that is, I can't think of any that would behave similarly...)




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[*] posted on 24-6-2004 at 03:14


Did you try it using NaCl as I said? Well, try another run and react ALL the products of the reaction with methanol.

There is a catch here, you have to wait until it cools, on the other hand, they absorb water from the atmosphere quickly, so keep the condensing bowl on top until all is below the bp of methanol. This also helps prevent the products (which I say contain lots of elemental sodium) from catching fire when exposed to fresh oxygen. Yes, it happened.

Edit:
Cyrus, I also doubt that you will distill sodium that way. If any is produced, it will stick to the walls along with by-products.

Why don't you try the can & water bowl procedure to know the reaction a bit better?

Know what? I'll try to make this thing work with al foil, just to see if someone else can obtain my results, I'm feeling a bit lonely here.
Well, soon...



[Edited on 24-6-2004 by Tacho]
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[*] posted on 24-6-2004 at 13:49


Tacho, as soon as my concrete blast chamber (It actually will have some concrete fiberboards) is finished, I'll attempt to duplicate your reaction with Mg, not Al, using the lower and upper bowls.

As for Na distilling, I think it sounds improbable too, but isn't that how the "ancients" made Na a couple hundred years ago? As in NaOH or Na2CO3 and Fe powder, in a charcoal furnace, the product vaporized and was condensed in a flask of some organic liquid, I forget which.




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[*] posted on 24-6-2004 at 14:05


The product was actually condensed in liquid lead. From there it was distilled yet again under an inert atmosphere. This is the old carbonate process that Du Pont used.



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[*] posted on 24-6-2004 at 14:28


I just remembered, I think it was naptha.

BromicAcid, you may be right, I cannot check, I am missing encyclopedia #16, where I saw the process.




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[*] posted on 24-6-2004 at 17:08


Cyrus, did you take a look at the papers about production of sodium that Bromic Acid made available some time ago?

There is a link somewhere in this thread. If you can't find it, PM me.

That is a must-read.




Edit: BTW, I tried to make some Al power using Al foil, a NaCl slurry and a blender. The result was disapointing. It was not a powder, more like crumpled flakes. IT DID NOT WORK in the thermite with NaCl and NaOH.

Edit2: Also, I did a small run of the thermite (1 spoon of NaCl, 1 of NaOH, 1of Al ), but this time, since I have recently bough a bag of ativated carbon powder, I added half a spoon of it to the mix, to see what happens.

I have the impression that the deposited sodium was less powdery, and I scraped some soft metal from a "drop" formed in the condenser. Maybe the improvement was just an impression, maybe it was because I used no carbonate, but if you have carbon powder available, may worth a try.

I keep having this metal that melts under the xilene in many about 2mm blobs, mixed with the powder (residue), but just won't aglutinate to one big blob. It's not an amalgam, because when it fizzes and disappears in water (no flames for small bits), it leaves no residue.

Guess I have to try paraffin as a solvent. Any other ideas?



[Edited on 25-6-2004 by Tacho]

[Edited on 25-6-2004 by Tacho]
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[*] posted on 25-6-2004 at 08:39


I started reading them, my computer is more than slightly slow though, (Win 95!)
I didn't get very far, but I will try again!

Tacho, melting the Na/impurities under an inert atmosphere might help. (if this is in a centrifuge it might help too) Then putting it in one of the perforated ladles described elsewhere will remove the NaOH, perhaps other impurities too. Maybe you could mount the ladle onto the centifuge. :P

Molten sodium filtering! That ought to work, but Na has a lot of surface tension, so it would have to be under pressure to drive the Na through the filter. Or under a vacuum to pull it through.

Sorry if I am rambling.




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[*] posted on 25-6-2004 at 13:16


Do not use teflon when working with alkali metals. The only thing teflon reacts with is with alkali metals and then it acts as an oxidizer. And a rather powerful one...



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[*] posted on 25-6-2004 at 14:37


To add to what vulture said, when PTFE and alkali metals combine free fluorine can be evolved in significant quantites.



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[*] posted on 25-6-2004 at 15:10
SODIUM!


Doesn't teflon react with molten alkali hydroxides also?

Edit: Just made some sodium, using an upper ice-cold bowl and the lower bowl to do the reaction in. I didn't measure anything out, just added NaOH and Mg till it looked right. I mixed these together a little in the lower bowl, and set this in my reaction chamber.

I was being ridiculously safe on this
one.;)

Then after heating for a minute or two, there were bright orange flames, which lasted about 10 seconds. I heated for another minute, just to make sure the reaction was done, and let it sit for 3 minutes. On the bottom of the lower bowl, there was a very thin white covering/paste, which when I scraped it into xylene, caught on fire in the air, some of it falling to the ground in burning spheres, some catching the xylene on fire. DON'T WORRY, I was prepared. I covered the can, the fire went out. Now xylene ought not to eat sodium, but the mixture started fizzing and frothing-this is from residual moisture I assume, could it be water from the fire itself? So that was all wasted. :mad: Will vegitable oil work?

Upon opening the lower bowl, there were about 6 different globs that glowed bright yellow. A couple minutes later, the globs had turned a dull pale green. The whole mass of reactants had hardened into a cylinder at the bottom of the lower bowl by now. This was lifted out, several sections looked metallic. Anyways, there were several extremely small balls of sodium that fell out from somewhere,
they fizzled in water. Ahh.

Sorry Tacho, I did not try the reaction with NaCl, Na2CO3 and NaOH. That will have to wait until tomorrow.

[Edited on 26-6-2004 by Cyrus]

[Edited on 26-6-2004 by Cyrus]




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[*] posted on 26-6-2004 at 08:00
Great Work! Congratulations!


Keep beeing careful!

I have never used Mg, but I can confirm 2 things:

1) Xylene DOES fizz a bit when you put sodium in it, probably due to residual water (maybe that's why they use sodium to dry organic solvents... duh!).

2) the little balls of sodium do NOT catch fire when tossed on water, they just dance on the surface, fizzing, until they disapear.

Also: Silicone oil is not good to keep sodium. It reacts. At least mine did.

I find the yellow and green colors quite surprising! I can't explain that.

Edit: I'm having a feeling that molten paraffin may be the best way to separate sodium. Keeping sodium in solid paraffin also sounds good.

[Edited on 26-6-2004 by Tacho]

[Edited on 26-6-2004 by Tacho]
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[*] posted on 27-6-2004 at 15:27


Later I put about 0.3 cc of the residue from the lower bowl into a test tube, and added about 2 ml of H2O. Wham, instantaneously, the test tube heated up, and a jet of orange flame shot out. Ahh, must be lots of Na, or is there? Earlier Tacho said that fire and H2 was not a definite indication of Na. What else could it be?
MgO? nope
Na2O? I don't think so. Na2O + H2O
->2NaOH.
The links by Polverone to Murspratt sp? on the first page of this topic suggest that other oxides of sodium may be formed-it mentions a dirty green NaO3 IIRC. That is what I believe the green residues are.

Filtering under paraffin might work, (murspratt? suggests dropping the liquid Na through course linen to remove impurities) but Na would be a pain to store that way. Just imagine all the hassle to get a piece out and seal up the jar again.

[Edited on 27-6-2004 by Cyrus]




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[*] posted on 28-6-2004 at 03:02


Quote:
Originally posted by Cyrus
(snip)What else could it be?
(snip)


I'm pretty sure you got sodium. Didn't you see little metalic balls that react with water? Well, I think that's it. Squeeze them, sodium is soft.
Would magnesium little balls react with cold anhydrous alcohol? Maybe that's another test.

The Al-NaOH thermite without NaCl yields a grey mass that reacts with water but has no sodium (doesn't react with dry alcohols). Many people have mentioned hydrides.

Quote:

(snip)
Filtering under paraffin might work, (murspratt? suggests dropping the liquid Na through course linen to remove impurities) but Na would be a pain to store that way. Just imagine all the hassle to get a piece out and seal up the jar again.

[Edited on 27-6-2004 by Cyrus]


On the other hand, liquid solvents keep absorbing moisture from air, like xylene, I think paraffin in a test tube would do a better job in keeping it. Just melt it using a flame before use.

[Edited on 28-6-2004 by Tacho]
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[*] posted on 29-6-2004 at 13:44


Yes, I got some sodium, but I was wondering what the other stuff was. Sorry for the dumb question I forgot all about hydrides.:(

I am planning to make a charcoal furnace, so then NaCO3 + 2C -> 3CO + Na. The Na vapors will bubble into molten paraffin.




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[*] posted on 29-6-2004 at 21:23
Castner


This is a patent from Castner.
He uses tar as the carbon source,mixed with iron oxide,which is then calcined in the absence of O2.
The reduction is told to take place @ red heat temps.
50%+ yeild from Naoh.

US342897
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[*] posted on 30-6-2004 at 03:47


Quote:
Originally posted by Cyrus
(snip)Na vapors will bubble into molten paraffin.


Sorry, but I doubt it. Sodium boiling point is 892ºC. It will condensate long before it reaches the paraffin. Or it will do terrible things to the poor paraffin when it gets there at this temperature.

[Edited on 30-6-2004 by Tacho]
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