NaBH4 patents-PolytheneSam

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Polythene Sam
(Master Searcher)
01-07-02 19:54
No 253798

Re:NaBH4 patents

I got the idea of looking through US class 423 subclasses 286, 287 and 288 to see if there were any methods of making NaBH4 that could be applied to a home brew method. I think the first patent in the list has a lot of potential. Some of them discuss the use of borohydrides as a source of H2 for motor fuels, etc.

3734842 electrolytic synthesis of NaBH4 from NaBO2
2942935 MgB2 --> borohydrides
3077376 borax to borohydrides
2898184 apparatus with three neck flask, Wood's metal bath
3253884 borohydride H2 source
3379511 NaBH4
3458531 IR spectra
3637516 cyanoborohydride
3993732 recycling LiBH4

5294423 The invention relates to a process for the preparation of an alkali metal borohydride. According to this process, a mixture of an
alkali metal hydride, boric anhydride and a hydrogenation catalyst such as Raney nickel is raised to a temperature of
250.degree. to 300.degree. C. under a hydrogen atmosphere.

6251349 Method of fabrication of complex alkali metal hydrides

I never heard of using a Wood's metal heating bath before (US 2898184). Imagine a smoke free high temperature bath at last, or would any of those heavy metals get into the air?

http://www.geocities.com/dritte123/PSPF.html

foxy2
(Distinctive Doe)
01-07-02 19:57
No 253801

Re: NaBH4 patents

Nice Patent Work Sam

There is a synth floating around Rhodiums Site that uses a Woods Metal Bath.

I hate my government, does this mean I'm a terrorist??

PloytheneSam
(Master Searcher)
01-07-02 20:17
No 253805

Re: NaBH4 patents

Yeah, we shouldn't assume things, ie. that NaBH4 can't be made at home.
http://www.geocities.com/dritte123/PSPF.html

PrimoPyro
(Hive Prodigy)
01-07-02 20:22
No 253809

Re: NaBH4 patents


I'm reading the first one now, Sam. Great find! This seems easy!

Electrolysis of alkalaine sodium metaborate solution gives the borohydride.

NaBO2 + 2H2O --NaOH/e---> NaBH4 + 2O2

Cool!

   PrimoPyro
Vivent Longtemps la Ruche!

PolytheneSam
(Master Searcher)
01-07-02 20:35
No 253814

Re: NaBH4 patents

A lot of processes use diborane. Not too easy to get or make. I had the thought of an electrolytic process at the back of my mind I think because of thinking about metal hydride batteries and the possibility of making hydrides in an electrolytic cell. That might be something else to look for in the patent literature or library. I wonder if lithium aluminum hydride could be made electrolytically. The electrolyte would probably have to be free of water.
http://www.geocities.com/dritte123/PSPF.html

PrimoPyro
(Hive Prodigy)
01-07-02 22:21
No 253850

Re:Electrolytic NaBH4 Production

The first patent in that list is by FAR the best procedure there, and the best procedure I've seen.

It's very straight forward. A container is bisected with a cationic exchange resin membrane, and a catholyte of aqueous NaBO2 (sodium metaborate) and an anolyte of aqueous NaOH are introduced, and an electrical current is applied.

The anolyte sodium ions, Na+ are attracted to the cathode, and pass through the membrane. This gives a high concentration of sodium ions in the catholyte. In the anolyte compartment, the hydroxide ions are oxidized to hydroxyl radicals, which decompose into water and oxygen.

In the catholyte compartment, the sodium ions are reduced to atomic sodium, which reacts with the water present to regenerate sodium hydroxide, and to evolve hydrogen. The hydrogen reduces the metaborate ions, BO2- to borohydride ions, BH4- These ions are attracted toward the cathode compartment, along with the hydroxide ions, but cannot pass through the cationically selective membrane, and are thus able to be isolated.

The anode reactions are:

1. 8NaOH ___> 2O2 + 4H2O + 8Na+ + 8e-
   (a) 8NaOH ___> 8Na+ + 8OH-
   (b) 8OH- ___> 2O2 + 4H2O + 8e+

The cathode reaction is:

NaBO2 + 8Na+ + 6H2O + 8e- ___> NaBH4 + 8NaOH

The reaction proceeds in normal aqueous medium, with concentrations as low as 0.1M solution; preferred concentrations are 1-5M solutions.

The current used ranges from 1.23V to 12V, preferred voltage being ~4V-6V.

Amperage can be as low as 0.1A/in.2, and up to ~4.0A/in.2, with a preference of ~1.0A/in.2
(Once again, units were copied from the patent, and are not my doing.)

The electrodes can be any conducting material, although it states that catalytic electrodes have been employed as well, i.e. Nickel boride, platinum, palladium, etc.

Temperature range is any convenient temperature up to ~80?C. Anything above this is not recommended, as borohydride ion degradation due to hydrolysis increases with temperature.

It is recommended that the starting catholyte solution be alkaline, (although acidic and neutral solutions will work,) and that an alkalaline solution be maintained, as it helps stabilize the borohydride ion, and minimizes decomposition due to hydrolysis.

Solutions of ~20-80% borohydride have been produced efficiently with this invention. It can operate at both higher and lower efficiencies to obtain higher and lower concentrations, but such operation is often wasteful of raw materials.

Patent US2731408 is cited as a specific example for the production of a suitable ionically selective membrane. Other cationic membranes will function as well, as long as they are not reactant with the reagents or products of this reaction.

Sounds pretty cool to me.

   PrimoPyro
Vivent Longtemps la Ruche!

PrimoPyro
(Hive Prodigy)
01-08-02 01:30
No 253910




Re:What other things can one reduce like this?

What about nitromethane? MeNO2 is soluble in water at 95g/L. Two different ideas here, but first a question: Can NaBH4 reduce Nitromethane to Methylamine? If so, then =

1.Instead of a straight sodium metaborate/water catholyte, use a sodium metaborate/nitromethane/water catholyte.

The produced borohydride ion reduces the nitro group to an amine, thus producing methylamine freebase.

2.Even better, Don't use NaBO2 at all. Use a nitromethane/water catholyte, and the "nacent hydrogen" as they call it, that reduces the borate ion to the borohydride ion, will reduce the nitromethane to methylamine.

Will either of these work? Especially --2!

Shit can you imagine how easy it would be to reduce nitromethane if that worked! You could use any ionic sodium compound: NaCl (only with a membrane to prevent Cl2 coming in contact with the amide), NaOH, Na2CO3, NaOOCCH3 (ethane and carbon dioxide emitted from anode, bee careful) and most wouldnt even require any membrane at all.

2Na+ + CO3-2 + 2H2O ___> 2Na+ + 2OH- + CO2 + 0.5O2 + H2

2OH- - 2e- ___> H2O + 0.5O2

It's a very simple, efficient cycle to produce hydrogen (and sodium hydroxide OTC), but will the hydrogen reduce the solvated nitromethane?

I would bee happy happy if it would.
But won't bee sad if it won't.

   PrimoPyro
Vivent Longtemps la Ruche!

halfapint
(Ubiquitous Precursor Medal Winner)
01-08-02 02:45
No 253934


Re: What other things can one reduce like this?

I've got a kind of liking for the second patent, myself. Magnesium diboride isn't as hard to come by as you might think. Goldschmidt found it as a by-product when he made elemental boron by reduction of boric acid or boric anhydride with magnesium. i.e., I could show you some in 10 minutes, but the last 9 minutes 58 seconds of that would bee waiting for that stuff to cool. (Anybody recall the red P thread Post 224224 (halfapint: "Re: Red P from Phosphoric acid?", Chemistry Discourse) that had the aluminothermy "Goldschmidt" approach in it?) Happens this MgB2 is useful in other ways too. With a Lewis acid, it gives diborane; heard it rumored that was hard to come by. If that happens in THF, it gives diborane/THF, a useful complex.

Last January, it was found to bee the highest temperature metallic superconductor.
Scientific American: Science and The Citizen: New Trick from Old Dog: June 2001

Magnesium boride overturned theorists' expectations and promises technological applications... the higher operating temperature [39K] would allow cooling of the superconductor by refrigeration instead of by expensive liquid helium.

Drop some in some lye water (or alcohol) and it gives you sodium borohydride. I should have known. To tweak the "thermite-type" reduction toward MgB2 instead of producing mostly boron, I'd try running it in a heat-retaining insulated crucible, to keep it hot longer than 10 minutes. Edit: Well, no, that wouldn't help, if the Mg was all oxidized away! Have to use excess Mg... [and then I had some more rambling that mostly shows Half-a-Pint needs to get to sleep.]
turning science fact into <<science fiction>>

Rhodium
(Chief Bee)
01-08-02 03:47
No 253949

Re: What other things can one reduce like this?

Now we just want someone to perform at least one of the preparations and then write an illustrated document about it.

PolytheneSam
(Master Searcher)
01-08-02 20:39
No 254213

Re: NaBH4 patents

Here's some boride patents. The first one is on an aluminothermic process.

3016288 aluminothermic process
1858413 calcium boride
2893841 MgB4
3253886 interesting apparatus
3379647 borides and carbides
3392059 Ni and NaBH4
4604368 AlB2

4038290 olefins to epoxides using a boride catalyst
http://www.geocities.com/dritte123/PSPF.html

PrimoPyro
(Hive Prodigy)
01-08-02 21:48
No 254249

Re: NaBH4 patents

Will NaBH4 reduce nitro compounds to amines?
Will NaBH4 reduce the phosphate ion to atomic phosphorus?
Vivent Longtemps la Ruche!

Chromic
(Hive Addict)
01-08-02 23:09
No 254272

Re: NaBH4 patents

NaBH4, by itself, does not usually reduce NO2->NH2. If other ions are present, NaBH4 could reduce NO2. (maybe Cu(I) - I don't know which specific transition element salts would do it...) NaBH4 would certainly not reduce PO4(3-) to P... it is not a strong reducing agent, it's often used because it's quite chemoselective compared to LaAlH4, etc.

Rhodium
(Chief Bee)
01-09-02 03:11
No 254341

Re: NaBH4 patents

Ni2+, Co2+, Cu2+ will activate NaBH4 enough to reduce NO2 to NH2, as will probably I2 and conc. H2SO4.

PrimoPyro
(Hive Prodigy)
01-09-02 08:46
No 254400

Re: NaBH4 patents

So CuCl2 would be a smart choice, having both the Cu+2 ion and the reducing I- ions?

I'm trying to find a way to reduce nitromethane in using NaBH4 generated in situ.

1.The NaBO2 is reduced by the H2 produced from electrolytic Na + H2O --> NaOH + H, yielding the borohydride.
2.The borohydride reduces the nitromethane to methylamine, regenerating water (some of it, not all) and thus oxidizing the borohydride, presumably to the borate ion BO2 again.

Makes me wonder two things:

1.Is the copper salt a catalyst or a reactant? I mean is it consumed or a true catalyst?
2.Could you omit the borohydride completely and just use the Na+ + e- + H2O ___> NaOH + H, to reduce the nitromethane?

PrimoPyro
Vivent Longtemps la Ruche!

Rhodium
(Chief Bee)
01-09-02 12:43
No 254444

Re: NaBH4 patents

Cuprous ions are reduced by iodide to CuI...

2 Cu2+(aq) + 2 I-(aq) __> 2CuI(s)

Chromic
(Hive Addict)
01-09-02 21:34
No 254616

Re: NaBH4 patents

Yeah, the activators of NaBH4 are catalysts. NaBH4 is a stoichiometric reducing reagent. Other things like Pd/C and Pt/C will reduce imines and MeNO2, and they are catalysts... the stoichiometric reagent in that case is (of course) hydrogen gas... isn't there a better reagent to use than NaBH4? Why not hydrogenate MeNO2, add ketone, and hydrogenate again?

PrimoPyro
(Hive Prodigy)
01-09-02 21:40
No 254622

Re: NaBH4 patents

Because this procedure is so forgiving of reaction conditions. I don't have a pressure vessel and a hydrogen tank. Nor do I have the extremely expensive PdCl2

PrimoPyro

Just curious about a new possibility.
Vivent Longtemps la Ruche!

halfapint
(Ubiquitous Precursor Medal Winner)
01-10-02 00:50
No 254695

Re: NaBH4 patents

NaBH4 makes a good partner with catalysts, like Urushibara nickel which doesn't use precious metal. A dissolving metal reduction in acid is cheap as it gets: Zn/HCl, Fe/HCl.
turning science fact into <<science fiction>>

UTFSE
(Hive Bee)
01-11-02 17:48
No 255453




Re: NaBH4 patents

Does this fit?

Thurston, Jack T. Preparation of boron from borax.
J. Chem. Educ. 1929 v6 p550.

OTEECEE & meeeee!!!!

UTFSE
(Hive Bee)
01-12-02 15:49
No 255697

Re: NaBH4 patents

I read and digested (HA) 3734842 and it is the bomb.

Thank you oh bees. and particular Poly Ethylene Sam ---you are de man. All hail the research department prince -
Dr/Mr/Ms Sam!!!

you don't have to have borate or diborane and it is possible to continuously produce (feedthru) both NaBH and KBH.
Probably other alkali metal borohydrides as well.

Sodium metaborate is piece of cake.
GB326378
Just boric acid and sodium hydroxide.
aka roach powder (teeheehee) and baking soda.
OTEECEE & meeeee!!!!

foxy2
(Distinctive Doe)
01-14-02 11:31
No 256286

Re: NaBH4 patents

sodium hydroxide is not aka baking soda
I hate my government, does this mean I'm a terrorist??

UTFSE
(Hive Bee)
01-14-02 20:31
No 256501

Re: NaBH4 patents

yeah that's right I crossed up two methods of making sodium metaborate