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Polverone
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Even better, heat and prod/stir it under xylene, toluene, kerosene, etc. Sodium has a nice low MP so this should be feasible and easier than working
with inert gas.
Congratulations Al Koholic, and thank you Tacho. Given how easily NaOH attacks aluminum, I wonder if a more common, cheaper form of the metal might
work (like foil, filings, or turnings).
Orgy: your electrolytic cell may work marvelously, but does it glow with heat and belch burning hydrogen? Does it?! I thought not. Tacho's method
gets more Mad Science Points for that reason. However, you may recapture the glory if you show us pictures of an operating Castner cell  .
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Tacho
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Thank you all,
Congratulations for those who could figure out the equations!
News:
1 - The gray residue does NOT react with anhydrous acetone, anhydrous IPA, anhydrous methanol nor 99,5% ethanol. After 12 hours , there was a bit of
white haze in the alcohols, the acetone has evaporated (duh).
2 - I could not make zinc powder react.
3 - About electrolisys of molten NaOH (I mixed a bit of NaCO3 too) using porous ceramic: bad news, it takes an incredible short time for the molten
NaOH to dissolve the ceramic and, worse , the residue in the ss reactor is very dificult to clean because, if you think about it - I didn't- you
are kind of making... glass.
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Saerynide
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This sounds like something to try over xmas break
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Theoretic
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I'm a bit dazed... The thread wasn't too interesting when it
was solely electrolytic, but the chemicalmethods surely livened it up!  I
don't believe my eyes!
Just one problem I see with the Na2CO3/NaNO3 + Al method... I think it would rather react to produce CO/N2 and NaAlO2...
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Marvin
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Polverone, Neuron reminded me the patent number a few months ago when I couldnt find it, its US4725311 I think. It deserved more attention than it
got.
Magnesium and sodium hydroxide being heated together without a solvent, themite style will also work but this is very exothermic and can prevent a
reasonable yeild.
Sodium hydroxide + aluminium will yeild a small amount of sodium. Mostly you get sodium aluminates and metaaluminates.
Magnesium does not form 'magnesates' which is why it doesnt have the same problem.
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vulture
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Won't the NaOH decompose into Na2O before the reaction starts, driving off H2O vapor?
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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Theoretic
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No, NaOH doesn't do that. Not at the temperatures available to a home chemist, anyway. Even sodium carbonate requires 1000 C to decompose.
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KABOOOM(pyrojustforfun)
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Theoretic:
<blockquote>quote:<hr>Just one problem I see with the Na2CO3/NaNO3 + Al method... I think it would rather react to produce CO/N2 and
NaAlO2...<hr></blockquote>CO reacts with Al
3CO + 2Al <s> ></s> 3C + Al<sub>2</sub>O<sub>3</sub>
<font face=symbol>D</font>H<sub>c</sub>=-1251 kJ
excess Al must be used with those methodes. even though I included sublimation energy for Na the reaction is still vety exothermic for NaNO3 methode.
the hardest part is to get a single piece steel retort <!--
[Edited on 10-12-2003 by KABOOOM(pyrojustforfun)]
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chemoleo
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Sodium nitrides
just wondered, how easily is sodium nitride produced (if at all) , analogous to Magnesium Nitride Mg3N2?
Surely this will interfere with the desired reactions if a N2 atmosphere (devoid of O2) is employed....adding an other impurity to the already
mentioned NaAlO2, NaAlH4 etc...
I guess the smell would tell upon dissolution in water, due to the formation of ammonia....
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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Hermes_Trismegistus
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Thanx Marvin for that sweet patent, I am not sure about the solvent he used for the actual example, but it seems that if the kerosene he suggested
worked I think you're in the money.
__________
the Castner Tiegel cell shows definite promise but I am dismayed both by the copious use of Nickel (200 bucks for the cheapest, thinnest 200 grade
sheet I could find, and that was only 12 inch by 12 inch)
It also puzzled me with the Condensed material at the bottom of the chamber and the wooden gasket?
I wondered if my babbling fish is really beginning to babble?
_____________
and Still !!! the thought of a down's cell gets my motor running...
I think I may be getting closer to the prize (ingots of sodium the size of a cpu tower)
I have ALWAYS wanted to throw one into a lake!!!
I just found out that Beer keg's are actually high grade stainless!
http://metals.about.com/gi/dynamic/offsite.htm?site=http://w...
Arguing on the internet is like running in the special olympics; even if you win: you\'re still retarded.
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vulture
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| Quote: | Originally posted by KABOOOM(pyrojustforfun)
<font face=symbol>D</font>H°<sub>f</sub> for NaNO<sub>3</sub> and
Al<sub>2</sub>O<sub>3</sub> are -424.8 & -1669.8 KJ
NaNO<sub>3</sub> <s> ></s> Na(s) + 0.5 N<sub>2</sub> + 1.5
O<sub>2</sub> - 424.8 KJ (in thermodynamic you can use any theorical equation)
1.5 O<sub>2</sub> + 2 Al <s> ></s> Al<sub>2</sub>O<sub>3</sub> +
1669.8 KJ
Na(s) <s> ></s> Na(g) <font
face=symbol>D</font>H<sub>subl</sub>= +108 KJ
1669.8-424.8-108=1137 so
<font color=green>NaNO<sub>3</sub> + 2 Al <s> ></s> Na(g) + 0.5
N<sub>2</sub> + Al<sub>2</sub>O<sub>3</sub> + 1137 KJ</font> 
Na<sub>2</sub>CO<sub>3</sub> <font face=symbol>D</font>H°<sub>f</sub>= -1130.9 KJ/mol
1669.8-1130.9-108=430.9
<font color=green>Na<sub>2</sub>CO<sub>3</sub> + 2 Al <s> ></s> 2Na(g) + C +
Al<sub>2</sub>O<sub>3</sub> + 430.9 KJ</font>
NaOH <font face=symbol>D</font>H°<sub>f</sub>= -426.7 KJ/mol
((1/3)*1669.8)-426.7-108=21.9
<font color=green>NaOH + 2/3 Al <s> ></s> Na(g) + 1/3
Al<sub>2</sub>O<sub>3</sub> + 0.5H<sub>2</sub> + 21.9 KJ</font> |
That's not correct IMHO. You need to substract the formation enthalpy of the reagents from the formation enthalpy of the reaction products.
Example:
A + B ---> C + D
DHf = HfC + HfD - HfA - HfB
So you should leave the minus sign infront of all the enthalpies. Recalculation shows exothermic values.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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BromicAcid
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I really like the Castner Cell and all, but with all the talk about chemical reduction to acheive sodium metal I decided to give it a whirl. Well,
kind of.... "The hydroxides or carbonates of the alkali metals -- 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.." [Inorganic and Theoretical Chemistry] So I chose potassium hydroxide and magnesium turnings to start...
1 Shows the reactants prior to any disturbance, 5 g of Magnesium turnings and 11 g of potassium hydroxide in prill form.
2 Shows the reaction in progress, I ran it in a soup can because I had all the reagents on hand and it was cold and I didn't
plan and it was easy to find. The top was closed but hydrogen evolution quickly gave a dull thud and poped it off and flames started rising above it.
The reaction started almost immediately as the bottom was heated with a bunsen burner. Some smoke and characteristic violet emmision of light.
3 Flames died down and I took a picture, you can't see it well but there were little potassium globules, when you blew on them
they would burst into flames, I closed the top and let it cool, being that it was 15 F outside it did not take long.
4 After it cooled down I moved the lid off, it caught on fire again when the air hit it. The top of the mass is greenish and molten
looking but quite solid on probing, I can break it up and potassium is visible in the matrix.
5 I slammed the container down on the picnic table to dump out the contents. It immediately burst into flames giving the
characteristic violet spectrum of potassium and continued burning for over a minute leaving a white ash that reacted with water releasing gas
(probably oxygen, potassium forms appreciable peroxide and superoxide when exposed to air).
6 On reaction with water of the solid left over with potassium in matrix it released hydrogen, caught fire, precipitated magneisum
hydroxide, you can see it at the bottom of the beaker.
So, it was pretty interesting. I chose magnesium over aluminum because it does not form compounds with aluminum as stated before: "With aluminum
metal in place of magnesium some alkali aluminate is formed, and the yeild is reduced considerably."
For example the carbonate:
3Na2CO3 + 2Al ---> Al2O3 + 6Na + (3CO2)
which competes with
3Na2CO3 + 2Al ---> 2Na3AlO3 + C + (CO2 + CO)
So that explains my preference for magnesium over aluminum and before I explained why I picked potassium hydroxide over sodium hydroxide although you
could probably use them interchangeably. Supposedly the mixture does not get hot enough to volitize the potassium, I can not vouch for this but if
this is the case the reaction vessel can be made from 2 inch wide pipe maybe 5 inches long with an end cap and a reducing piece to put it down to say
3/4 in. diameter and then you can put a 45 deg. piece in place and make a metal retort. Heat the reaction mixture and continue to do so after
reaction and distill over the sodium metal. Supposedly the sodium vapor is cooled in molten lead then distilled from that later, a bit impractical
but what the hey.
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Alkali
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Congratulations for your experiment, it's really interesting!!
Just one suggestion for you to try it once again: Why not covering the mixture (magnessium turnings + KOH) with sand so you could preserve the
metallic Potassium formed in a better way so you could then add mineral oil and pass potassium pieces on a separate container with mineral oil!!??
I have plenty of Sodium metal at home (more than 1 Kg of it) and 1 Kg Strontium Chloride. I'm planning to obtain Strontium metal reducing the
chloride with my sodium by adding it inside an inverted container over the fused strontium chloride so the strontium metal does not oxidise once
it's being formed. What do you think? Would be a really interesting experiment to perform, don't you agree?
[Edited on 13-12-2003 by Alkali]
[Edited on 13-12-2003 by Alkali]
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unionised
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unconventional sodium
Sand will react with Mg or with KOH or with K.
Perhaps something innert would be better. MgO for example.
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Tacho
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Congratulations BromicAcid! I’m stunned! Potassium using Mg, that’s great!
My experiments, in the other hand are not so impressive. In fact, they are very disappointing.
I tried the NaOH/Al thermite on a larger scale to confirm metallic sodium deposition.
I took pictures of the setup, but I still don’t know how to post them here. I could not use the FTP to this server (?). Any easy way? Whats that
attachment button for? Whats the insert picture button for? Sorry, but I'm sure I am missing something obvious here.
I used a lager stainless steel cup and dish (dish more like a bowl)
..|..................| bowl
..|_________|
........|.....|
........|_._| cup
(aargh!, dots everywhere, I can't get even ascII drawings right here)
I used about four spoons of NaOH and four of Al powder. I covered the cup with the bowl and put ice/water in it (the bowl). The reaction started very
soon after the blowtorch was set (about 2 min.) and lasted for about one minute, yellow/orange flames coming out. By the way, there was a loud
“pop” before the reaction began, it was the hydrogen inside burning, anyone trying this reaction in larger scale should remember that
hydrogen. After the reaction was over, I quickly poured the water and dipped the dish bottom in xylene to prevent oxidation and then scraped the
deposits to the xylene. Here things began to go wrong. The deposit was brittle and not metallic. I tranfered the deposit to a pyrex tube and tried to
melt the sodium. Funny things happen here: The xylene boils and stirs everything inside, making a sedimentation of molten sodium (if there was any)
impossible, besides, the few droplets of water that went into the xylene (ice in the dish=condensation) go to the bottom, happily reacting with
anything they find.
I got no metallic sodium, only the gray cement-like residue.
It is a fact that, soon after the reaction is over, the deposits on the walls of the cans, pans, whatever, react with water to produce yellow/orange
flames but, sadly, this is not the idiot-proof method of producing sodium I though it would be.
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Organikum
resurrected
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Bromic
congratulations!
Dont forget the license fee for the soup-can.
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BromicAcid
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My number one reason to post the pictures.... they looked neat. To get this reaction to work right I would use a 5 inch long 3 inch diameter pipe
threaded at both ends with end caps. I would drill a hole about 1/8 inch or so in diameter on one and and leave the other.
These pipes are exceedingly thick and resillant to pressure. The hole serves as an exit for the hydrogen gas but I would buy a piece of pipe exactly
the size and force it in, I would pack the smaller pipe full of steel wool to try and condense out sodium vapor and allow more cooling surface.
Immediately upon initiation of the reaction I would attempt to light the exit gasses so they would burn off as the reactoin proceeded, being under
hydrogen pressure some of the sodium would convert to the hydride. Experimentation or additional calculations would have to be done to make sure the
hole for the exit gas was wide enough to pervent an excessive hydrogen pressure on sodium, one atm of hydrogen = no reaction usualy, several and we
might have a problem. But if you're really hyped up about putting some inert substance over top of the reaction mixture give magnesium oxide a
shot.
Anyways, when the reaction started to die down you could put a weight over the exit area exactly like a pressure cooker and that would keep an inert
atmosphere inside. Wait to cool, then remove endcap and put contents into xylene, heat to mp of sodim with stirring, breaking up the chunks with a
stirring rod then hopefully with it's low density it will rise to the top of the reaction byproducts and seperation will be feasable.
But mainly I just did this to see what it would look like, if anyone wants to continue this further I would highly recomend the use of magnesium in
place of aluminum for the reduction. Local scrap yards will sell magnesium to an individual for $.70 a pound then just sand it to a shiny finish,
take a large drill bit to it and collect the shavings, very very little atmospheric oxidation.
Personally any further work I do will be on the Castner Cell although I am looking foreward to seeing if anyone can perfect this method as well.
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KABOOOM(pyrojustforfun)
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vulture: I put the realized energy into right side of the equation . eg 1137 KJ is realized from the nitrate flash mix which means <font
face=symbol>D</font>H = -1137 kJ
anyway I shall do the calculation for Mg
HBr! I love that purplish flame
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Theoretic
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I think that aluminates are actually intermediates in the process, since first aluminium mreacts with the hydroxide forming oxide and aluminate, which
react to produce a different aluminate. Then the sodium ions can finally be reduced to sodium.
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chemoleo
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Reduction of Aluminates
with reference to Marvin's statement:
/ Aluminium and sodium hydroxide is supposed to go mainly to Na3AlO3, a mixture that was formerly used to defrost oil wells and which produces no
sodium directly, formation of sodium is a side reaction with the coproduction of sodium metaaluminate. Magnesium seems the only feasable metalic
reducing agent which limits most peoples ability to use this.
I agree that side products *might* be the formation of aluminates. However, what I dont understand is why an excess of Al would not reduce that, too.
After all, why is this reaction
Al(ONa)3 (or Na3AlO3) + Al --> Al2O3 + 3 Na
not possible???
Those sodium aluminium oxides could only persist (under conditions of free Al and heat) when the reduction of the Na+ to Na would require more energy
than the oxidation of an additional Al produces!
Now is that the case?
[Edited on 15-12-2003 by chemoleo]
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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vulture
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Bless the great Ur of Al2O3 which makes this all possible...
Look up Born-Haber proces.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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KABOOOM(pyrojustforfun)
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MgO <font face=symbol>D</font>H°<sub>f</sub>= -601.8 kJ/mol
NaNO<sub>3</sub> + 3Mg <s> ></s> 3MgO + Na(g) + 0.5N<sub>2</sub> <font
face=symbol>D</font>H=424.8+108-(3*601.8)=-1272.6 kJ
Na<sub>2</sub>CO<sub>3</sub> + 3Mg <s> ></s> 3MgO + 2Na + C <font
face=symbol>D</font>H=1130.9+108-(3*601.8)=-566.5 kJ
NaOH + Mg <s> ></s> MgO + Na + 0.5H<sub>2</sub> <font
face=symbol>D</font>H=426.7+108-601.8=-67.1 kJ
I don't know the heat capacity of the products at different temperatures. if I had the data I could calculate their T
Marvin: lol I forgot "his" Os
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Saerynide
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| Quote: |
MgO DH°f= -601.8 kJ/mol
NaNO3 + 3Mg > 3MgO + Na(g) + 0.5N2 DH=424.8+108-(3*601.8)=-1272.6 kJ
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Holy hell!! Thats A LOT of heat I think I now understand the power of
nitrates...
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KABOOOM(pyrojustforfun)
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that was what I wanted to point out. more Mg is consumed than the other methods but its being so hot is very useful, as the chemical ways of
preparation of Na are best down at the highest T possible. it should propel gaseous Na! which can be distilled all without use of an outside heat
source (it would be kinda hard if one has to distill the impure Na he's already made)
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BromicAcid
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Here is an idea that Ive been rolling around regarding the recovery of sodium product from a chemical reduction. Apparatus, two 5 inch pieces of 2 in
wide pipe, threaded on both ends, one end of each pipe sealed with an endcap. They are hooked together by a step down sizer going from 2 to 3/4 inch
diameter with a 1 in 3/4 in pipe connecting the two together. In one of the large pipes, a hole is drilled approx. 1/4 inch diameter near the endcap
and a small length of pipe is run about 4 inches up.
Fill pipe A without hole with enough reaction mixture to stay safely below the hole connnecting it to the pipe on the other side when on its side.
Pack pipe B with steel wool fairly full being sure to put a plug of it in the opening of the little pipe on the inside put apparatus together being
sure that smaller pipe is sticking up and trying not to get any of the reactiong mixture into pipe B.
So start the reaction by applying heat. Sodium metal is reduced and with additional heat applied vaporized. Hydrogen pressure prevents excessive
reaction. Sodium metal condenses out on the steel wool in the second pipe and hydrogen gas comes out of the smaller pipe where it would be ignited.
Additional heat would be supplied to the pipe where the reaction would be taking place after initial reaction subsided to facilitate additional
recovery. Cover top of smaller pipe to prevent atmosphere from entering and wait to cool.
Finally after it is cool unscrew pipe and quickly dump steel wool into Xylene. Carefully heat with stirring and pull out the steel wool from the
molten sodium. Allow to cool and store ingot under xylene or kerosene.
Of course this all rests on sodium not alloying with the steel. Now I'm
planing on not posting here till I fish my castner cell, my downs cell, and perfecting my chemical reduction and comparing them this summer, so
don't draw me back!
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