testimento
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Sodium hydride and borohydride
I found the old topic concerning the NaBH4:
http://www.sciencemadness.org/talk/viewthread.php?tid=3151
I've been looking for a decent route for NaBH4 and have found only limited data. Few sources cite that it could be made from reaction between NaH and
borax or borosilicate glass at 250-350C.
Although the problem arises from the NaH production. From there it should be trivial to react it with borax or borosilicate glass. The sources cite
that one should flush molten sodium with hydrogen gas. I have also found other suggestions.
There is a reaction between magnesium and sodium hydroxide, which is supposed to release sodium metal, magnesium oxide and hydrogen, but one source
cited that it actually produced sodium hydride.
Another source cited that one should be able to produce NaBH4 directly by mixing sodium hydroxide and borax or borosilicate glass and heating them up.
Also my own idea, from carbothermic reduction arised a question, should NaOH + C be forming CO and NaH upon heating to melting point or upwards?
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bfesser
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You mention all these 'sources', yet I see no citations in your post. Either provide links to the references, or stop wasting our time.
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Zyklon-A
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| Quote: |
There is a reaction between magnesium and sodium hydroxide, which is supposed to release sodium metal, magnesium oxide and hydrogen, but one source
cited that it actually produced sodium hydride. |
I don't know what conditions are required to make NaH, (if that would work at all), but the normal reaction produces sodium, not sodium hydride.
NaOH + C--> CO + NaH wont work either, I suggest just making sodium, then 'burn' it in hydrogen, to make sodium hydride.
[Edited on 1-2-2014 by Zyklonb]
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Theoretic
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| Quote: |
NaOH + C--> CO + NaH wont work either, I suggest just making sodium, then 'burn' it in hydrogen, to make sodium hydride.
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with the reaction of NaOH and C you produce Na and H2, so depending on the way you cool the off-vapors from the reactor, you will form NaH
directly. It might be possible to have reducible boron material (borax etc) reduced in situ together with the NaOH, and form NaBH4 directly
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Zyklon-A
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with the reaction of NaOH and C you produce Na and H2, so depending on the way you cool the off-vapors from the reactor, you will form NaH directly
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Yes, but yields will surly not be 100%, so your product will still have to be reacted with H2 if purity is desired.
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testimento
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If it was possible to circumvent the need for electrolysis of liquid NaOH by carbothermic reduction, I'd prefer it because I dont have proper cell for
this at the moment and don't need it neither. Hydrogenization with external source is way more easier even for crude product.
How the NaBH4 could be separated most easily? Solubility data compared to the residual? Separation by melting one of the impurities?
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Zyklon-A
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You should read about making sodium in the unconventional sodium thread. A lot of your questions are answered there, as well as many new methods that may be useful to know.
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testimento
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I performed a test today with 1mol NaOH and 1mol C and heated them up with propane burner and got solid mass which whizzled a little when water
applied, but reaction was far from sodium+water.
The purification of sodium hydride from carbon residues will be PITA, so I'll probably just pack up the cell and make some sodium by electrolysis.
Have got the equipment around anyways. 
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Zyklon-A
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Have you tried NaOH+MG or Al? I'm sure that will work better.
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testimento
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Yes, I tested it a long time ago for other purposes and it certainly generated some Na or NaH, but currently I've run out of both fine metals and will
do no more testing until I get my ball mill ready. I cannot buy any of these substances in my country. Even purifying baking soda would be classified
as preparative terrorism or something like that. 
[Edited on 3-2-2014 by testimento]
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Zyklon-A
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Where do you live? How could they charge you for that? How can NaHCO3 be used to make a bomb? Anyway, I will either make or buy some
NaOH this week, so I'll try to make some sodium as well, I don't want it to make sodium borohydride, more like sodium for an element collection but
that's beside the point.
[Edited on 3-2-2014 by Zyklonb]
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Cou
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Just react sodium with hydrogen gas, the same way you would make NaCl by heating sodium in a flask filled with chlorine?
http://www.sciencedirect.com/science/article/pii/S0378775305...
[Edited on 5-4-2016 by Cou]
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chemrox
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You haven't tried any relevant searches. Otherwise you would have found at least three detailed procedure.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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