Hydrazine preparation: anhydrous processes

[meselfs]

Well... this is my first new thread, please be patient with this enthusiastic little n00b :o .

I've been interested in hydrazine for a long time. Please, don't tell me "astrolite is for kewls" or "it causes cancer", I've read up thoroughly about this and I understand the pro's and con's.

Now, every preparation method I've read includes the reaction of either ammonia or urea with a hyochlorite. I've never tried this method, and probably never will for many reasons, but most important of all is that you gotta seperate the hydrazine from water, and because using jello just sounds like a Mickey-Mouse operation to me. Also a waste of chlorine, and very little end hydrazine for the liters of fluid you deal with.

The only other method I found was this:

H2NCl + H3N --> H4N2 + HCl

I haven't toyed with this either, because the result is hydrazine chloride. To get pure hydrazine, you'll need to mix it with a hydroxide, which means more water, which means (getting monotonous?) a nerve killing distillation.
Also, how do you make chloramine without making nitrogen trichloride?



But today, I was searching info about hydrazine, and this came up:

http://www.booksmatter.com/b0471415537.htm

It'a 2000+ page exclusively about hydrazine. The price is 425$, I found used books cheaper, but still way out of what I'd pay.
But anyway, that link lists the table of contents, and this little bit is VERY interesting:


Preparation of Hydrazine from Ammonia
Preparation of Hydrazine by Photolysis of Ammonia
Preparation of Hydrazine by γ-Radiolysis of Ammonia
Preparation of Hydrazine by Glow Discharge in Ammonia
Preparation of Hydrazine in an Electric Arc Plasma and Other Hot Flames
Preparation of Hydrazine by Electrolysis of Ammonia
Preparation of Hydrazine from Ammonia by Chemonuclear Processes
Preparation of Hydrazine by Chemical Oxidation of Ammonia
Preparation of Hydrazine from Urea
Preparation of Hydrazine from Compounds with A Nitrogen-Nitrogen Bond
Preparation of Hydrazine from Semicarbazide
Preparation from Nitramide
Preparation of Hydrazine from Nitrosamine Derivatives and Nitroso Compounds
Preparation of Hydrazine from Nitrogen Oxides
Preparation of Hydrazine from Azo and Diazo Compounds
Preparation of Hydrazine from Inorganic Nitrides and Azides


Of particular interest to me are:
Photolysis of Ammonia
Glow Discharge in Ammonia
Electrolysis of Ammonia
Nitrogen Oxides


I've searched about all of these, and here are my schittey findings:

Photolysis of Ammonia

http://newjournal.kcsnet.or.kr/main/j_search/j_bkcs_archives_view2.htm?code=B960909&qpage=j_bkcs&spage=j_bkcs_01

(make sure you download the pdf)

Basically, it says that aqueos ammonia exposed to UV but sealed from oxygen will turn into hydrazine.

It's aqueos, but still interesting... it'd be incredible if you could just leave ammonia outside in glass with a relief valve (for the hydrogen) and end up with hydrazine solution a month later.


Glow Discharge in Ammonia

I read up a bit on glow discharge. It seems to be something like a low temperature plasma caused by 2000 V in low pressure (around 150 torr).
These are conditions which I can attain, but this is of concern:

http://www-2.cs.cmu.edu/afs/cs.cmu.edu/user/mnr/st/std091

It makes it sound like it's a difficult process. This isn't suprising: since hydrazine is used a monopropellant, I can't imagine how it would survive a 2000v spark... also that text states it must be highly turbulent flow, I imagine that the whole setup would be complicated to make.

Also, just as in NOx fixation, you probably won't get near 100% yield, meaning you'd have to recycle the ammonia, making things even more complicated.

Electrolysis of Ammonia

This I'm very, very interested in. I must've spent 2 hrs googling earlier today... found nothing, except that electrolysis of ammonia yields hydrogen and nitrogen, which apparently is an idea for fuel cell hydrogen source (sounds severly backward to me: using electricity to make a chemical to make electricity).
I'm kinda poor with electrochemistry, does anybody have any info on this? I'm guessing that at a certain voltage you get hydrogen plus nitrogen, but at another voltage you'd get hydrogen plus hydrazine. Anybody have a clue to what the voltages might be? Can they be calculated?
Also, what's the smartest electolyte (pure ammonia wouldn't conduct)? A bit of water, maybe? Some salt that can in the end be removed with some sort of voodoo?
Would this work for some good old 30% ammonia solution? But then you got the water problem...

Nitrogen Oxides

This is intersting to me mostly because I can probably make nitrogen tetroxide very cheaply (I'm working on it with confidence, might post about this if I can refine it). It almost definitely would produce water, but that's an OK compromise if the process is simple.

I found absolutely no info about this.


Well, that's all. I've called every freaking library and bookstore within a 200 km radius asking if they had that book, all came negative.

Does anyone have any info to contribute? Or by any chance access to that book?

I might experiment in a month or so, if I find anything I'll post.

[Marvin]

There is a fair amount of general information in this thread on wet processes,

http://www.roguesci.org/theforum/showthread.php?t=943

As for use of gelatine being a mikey-mouse process, its purpose is fairly simple. Lock up any copper ions in solution to prevent a very fast side reaction that produces nitrogen instead. Tap water for example contains enough copper ions to make the reaction fail almost completely. Glue or EDTA will work, but less well. NH2Cl + NH3 is part of the standard Rashig synthesis I would have doubts about feasabilty outside of aq solution.

If you want hydrazine for astrolite, I suggest you forget it. Astrolite is only feasable if you can just buy the stuff. If you want it for something else small amounts are possible but one hell of a chore and you may have no choice but to go via a wet method and several distillations.

The urea process has a major advantage over ammonia - you dont need a massive excess to get decent yeilds. Several methods are around including a good one by Mr Anonymous together with slightly over emphatic directions and this may be the best option. Urea, bleach and sulphuric acid are cheap, the yeilds are reasonable and we know this works. From the hydrazine sulphate produced the steps are very well documented and silvering glassware might not protect it completely. I also think this is one of the compounds that can explode on contact with ground glass joints (Detail needs cheking but watch out anyway anyone trying this). you will also lose product every step of the process.

"but most important of all is that you gotta seperate the hydrazine from water"

The vast majority of the water is removed by the formation of the hydrazine sulphate salt. Reaction of this with a strong base gets you strong hydrazine hydrate or better (meaning mixture of the hydrate and anhydrous) which can be distilled off, from there its 1 more distillation also with silver or silver coated equipment. If you can make the hydrate or even a weak solution in water, it is possible to make hydrazinium borate from which the anhydrous hydrazine can just be distilled off directly after dehydration. Somewhere also there is mentioned an entraining method for dehydrating hydrazine hydrate to anhydrous. Possibly megalomanias website, but discussed here also with some corrections.

Glow discharge I would think would be a major feat of engineering. What might work instead, and I'd put my money on for an easy route to (very) small amounts is a silent discharge in the same equipment we'd use to make ozone.

Electrolysis is new to me, but I'd bet sizable money the electrolyte is sodium amide in anhydrous ammonia, and that the primary hydrazine forming reaction is NH2- => NH2. + e at the anode followed by 2NH2. => N2H4.

If you are willing and able to handle liquid ammonia, making a hydrazine salt is not so far from anhydrous ammonia, as ammonolysis will turn it into hydrazine and an ammonium salt (which ppts), decanting and a fairly easy distillation of the ammonia gets you anhydrous hydrazine.

There is an alternative method to one step anhydrous hydrazine based on an old patent, but it has 2 major disadvantages.
1, The byproduces are ungodly toxic,
2, it doesnt actually seem to work.
Depending on how desperate you are you may want to look this up and try it at considerable risk to your helth if you succeed.

After some very heavy research on this whole hydrazine topic during the last 10 years Ive found no easy answers, very few sneaky shortcuts and substatially inorganic processes dont seem to have changed in the past 50 years.

[kurtz]

Photodecomposition of NH3:
JCS 1160-1169, 1932
JACS 55, 1754-1766, 1933
JACS 54, 1806-1820, 1932
JACS 56, 318-323, 1934
JACS 49, 2438-2456, 1927
JACS 58, 2462-2467, 1936
J Phys Chem 42, 783-788, 1938
Nature, 142, 1080, 1938
JACS 59, 827-830, 1937
JACS 51, 2059-2082, 1929

They obtained a 57% yield (based on decomposed ammonia) in the JCS article.
Unfortunately only .1% of the NH3 reacts. So 1 ton NH3 = 1 lb. hydrazine. Hydrazine is also photosensitive.

Electron Bombardment:
Proc. Roy. Soc. 130A, 346-366, 1931

Electrolysis:
Nature 125, 709, 1930
Trans Faraday Soc 31, 792-797, 1935
Nature 119, 235-236, 1927
Trans Faraday Soc 39, 234-237, 1943

Only traces of hydrazine can be obtained through electrolysis of aq. ammonia, at least with the (1915) ref that I was able to find.

As for NxOx, perhaps the involvment of these is to form intermediates, rather than being a reactant itself?

And you said nitramide was useless! Probably not as useless as the above. It seems that research did not continue for long. No one in industry, anywhere, uses such processes. Of all the Bizzaro ways to make hydrazine, you seem to have picked the least practical ones.:) So you'll really be needing those refs.

[Microtek]

For sodium azide production I use a method which gives hydrazine in alcohol ( from hydrazine sulfate ) with little or no water:

- 1 mol dry HS is placed in a flask along with a suitable amount of anhydrous isopropanol.
- 1 mol of NaOH pellets are added and the contents are triturated with a glass rod until they begin to react, forming a slurry of hydrazine hydrate and NaHSO4. This doesn't mix with the iPrOH, but forms a sticky goo on the glass.
- Another 1 mol NaOH is added which converts the NaHSO4 to Na2SO4 ( and forms a mol of water ) which separates cleanly as a white powder.
I would think that the Na2SO4 is a good enough dessicant to dry out the solution which can then be decanted.
- Another extraction or two with dry iPrOH recovers most of the hydrazine.

This alcoholic solution of hydrazine works well for producing sodium azide with isopropyl nitrite.

[meselfs]

As for use of gelatine being a mikey-mouse process, its purpose is fairly simple. Lock up any copper ions in solution to prevent a very fast side reaction that produces nitrogen instead. Tap water for example contains enough copper ions to make the reaction fail almost completely. Glue or EDTA will work, but less well. NH2Cl + NH3 is part of the standard Rashig synthesis I would have doubts about feasabilty outside of aq solution.

Would that mean they have chelating properties as well? That would make alot more sense...

If you want hydrazine for astrolite, I suggest you forget it. Astrolite is only feasable if you can just buy the stuff. If you want it for something else small amounts are possible but one hell of a chore and you may have no choice but to go via a wet method and several distillations.

Not exactly astrolite. I want to see if I can make azides with it (maybe even hydrazine azide?), and see what'd happen if I mix it with some certain oxidizers I have in mind...

Reaction of this with a strong base gets you strong hydrazine hydrate or better

That's exactly why I don't want a wet process: hydrazine free of water is tough to make. For many reactions the hydrate is fine, but if the hydrazine is used directly it's a bad idea thanks to it's negative heat of formation. Pure hydrazine is much better.

Glow discharge I would think would be a major feat of engineering. What might work instead, and I'd put my money on for an easy route to (very) small amounts is a silent discharge in the same equipment we'd use to make ozone.

I don't think an ozonater would work since ozone's formation is more endothermic and since ozone is less sensitive in some ways.

Electrolysis is new to me, but I'd bet sizable money the electrolyte is sodium amide in anhydrous ammonia, and that the primary hydrazine forming reaction is NH2- => NH2. + e at the anode followed by 2NH2. => N2H4.

If you are willing and able to handle liquid ammonia, making a hydrazine salt is not so far from anhydrous ammonia, as ammonolysis will turn it into hydrazine and an ammonium salt (which ppts), decanting and a fairly easy distillation of the ammonia gets you anhydrous hydrazine.

I don't think anhydrous ammonia is too much trouble, I was planning on making some later on for different needs. The fact that none of the reactants contain oxygen is very attractive to me :)... I also think this method has hope because you say you've been at it for 10 years but haven't toyed with electrolysis much.

Only traces of hydrazine can be obtained through electrolysis of aq. ammonia, at least with the (1915) ref that I was able to find.

Well, I won't even try that then. But I'm still most interested in dry ammonia electrolysis.

And you said nitramide was useless! Probably not as useless as the above.

I didn't say it was useless... but nitramide is hard to make and hard to work with. I haven't found any easy synthesis', if you have one, can you state it?

Of all the Bizzaro ways to make hydrazine, you seem to have picked the least practical ones.

I personally think that's likely, but there's a slight chance that we might come up with something anyway...

No one in industry, anywhere, uses such processes.

Did you know that you can make sulfuric acid by boiling sulfur with nitric acid, and then collect NO2 vapor to recycle the nitric acid? That's easy, right? So why doesn't the industry use it? Because it's very easy for them to pass sulfur dioxide and oxygen through near molten catalysts.
The industry uses the method most practical for them, and the professional chemists use methods that yield very pure products with minimum hazard. Us home improvisationist-chemists are left in the middle to fend for ourselves, and often we'll use something that seems like a miracle to use but severly impractical for everyone else.

[Rosco Bodine]

The value of hydrazine for our purposes is limited to the usefulness
of hydrazine as a precursor in the synthesis of several different types
of primary explosives . Such a need is satisfied by the use of
hydrazine sulfate directly in some reactions . Other reactions require
the hydrazine hydrate freebase which may be obtained from the hydrazine sulfate
by reaction of the solid with solid sodium hydroxide , and the absolute minimum
of added water to form a thick slurry of sodium sulfate crystals in hydrazine hydrate ,
which is taken up in successive portions of methanol . Proper technique and glassware
is needed for reactions involving the freebase hydrazine since it is destroyed
fairly rapidly by exposure to oxygen of the air .

For lab scale synthesis of hydrazine sulfate , the reaction of urea and
sodium hypochlorite is the best method . There is an extensive detailed
description at the Hive . That process is superior to any other published
method for lab scale synthesis of hydrazine from common materials .

The reaction of a slight excess of isopropyl nitrite with a cold methanol solution
of hydrazine hydrate and slight excess of sodium hydroxide , in a slightly pressurized
reaction flask produces a solid precipitate of pure sodium azide crystals in pretty good yield .
A pressure relieved , sealed glass and teflon reaction flask and addition funnel ,
with magnetic stirrer and an ice water bath is needed for performing the synthesis .

Regarding isopropyl nitrite ,

The isopropyl nitrite needed for the synthesis of sodium azide may be prepared
in advance and kept cold in the freezer , stored in a glass bottle having a teflon gasketed
threaded closure . The isopropyl nitrite may be made at salted ice bath temperature ,
by fairly rapid addition of a freezing cold mixed solution of aqueous 31.45% HCl and
a slight excess of theory of 70% isopropanol , to a well stirred freezing cold aqueous solution
of sodium nitrite in slight excess of theory which has been dumped onto twice its volume
of ice cubes in a flask which is cooled by a salted ice bath . The HCl in isopropanol should
be introduced through a small bore teflon tube extending downward to near the bottom
of the stirred mixture of ice cubes and sodium nitrite solution , or else it will decompose
the isopropyl nitrite which rises to the surface as it forms , if the acid mixture drops onto the
surface and contacts the free ester . It is very important for this reason to introduce the HCl in
isopropanol , near the bottom of the flask to avoid the decomposition of the product .
When all the HCl isopropanol has been added , the stirring is stopped and the isopropyl nitrite
top layer along with some of the lower layer of byproduct salt water is quickly decanted into a
prechilled separatory funnel , and the lower layer drawn off and discarded . The oily ,
bright yellow isopropyl nitrite layer is drained into a prechilled glass bottle having a
teflon gasketed closure , sealed only moderately tight to allow for a bit of overpressure relief
if needed , and stored in a freezer . The storage bottle and cap should be preweighed
so that the added weight of the isopropyl nitrite product can be determined , and it will be known
what molar amount is available for use of this precursor in further reactions . The isopropyl nitrite
fumes freely in the air , producing nitrous fumes from decomposition , as well as fumes from
the intact ester which has a volatility similar to ether . These fumes are highly toxic and physiologically active ,
as is the liquid ester itself so due caution should be observed to avoid inhalation or skin contact .

[meselfs]

Well... thanks for the info but I've searched this forum already and the internet in general, and I'm well aware of those methodes.

Concerning the azide, that's a very nice procedure. I'd read about it here and there on this forum but not in such detail. Thanks :D.


Concerning electrolysis, I found this (from a chemistry book genuisly titled 'Chemistry'):

N2(g) + 5H+(aq) + 4e- <——> N2H5+(aq)
E0 (V) = -0.23

Obviously the part about (aq) has been ruled out, but could this bit of info be useful otherwise? Like I said, I suck at electrochemistry...

[Pb1]

I just had a thought on the NH3 + NH2Cl method. NH2Cl is one of the intermediate chems involved in the synthesis of NCl3, which doesn't react to form NHCl2 and NCl3 at a certain pH. Is there any chance of synthesizing it by passing Cl2 into an ammonia solution at a carefully-controlled pH?

[Rosco Bodine]

There is really no need for producing hydrazine in anhydrous condition
for use in syntheses where hydrazine is used as a precursor for explosives .

Hydrazine hydrate and its methanol solution with sodium hydroxide does
not attack the unground surfaces of borosilicate glass , and only very slightly
clouds the surface of ground joints , which may be protected from such
slight attack by a film of Halocarbon grease or even Dow Corning High Vacuum
Silicone grease . There is no explosion hazard for the ground joints in
contact with hydrazine hydrate vapors , as is a concern for diazomethane .

Rocket propellants and some pharmaceutical syntheses are places where
the anhydrous hydrazine may be needed , and the expense and hazard
justified . With regards to astrolite , well there are cheaper and safer and
more powerful explosives which don't require hydrazine in any form .

Electrochemical methods are generally less desirable than direct chemical methods
for small scale production .

[meselfs]

Hmnn... ok I'll put electrolysis on hold (sorry, but I'm doomed to try it one day).

What about the ordeal with nitrogen oxides? Anyone have a clue how'd they work? It makes no sense to me since NOx + hydrazine = hypergolic propellant.

Edit:
Concerning the glass, Merck says:

For hydrazine: Can be stored for years if sealed in glass and kept in a cool, dark place.
For hydrazine hydrate: Strong base, very corrosive, attacks glass...


I don't plan to make astrolite ever but I'd prefer anhydrous because you can do more with it I guess.

[Rosco Bodine]

Those Merck references or their quoting are exactly backwards .

Unless there is some truly exceptional specific requirement for the
anhydrous form of hydrazine , the pursuit of making and storing it
is not justified because of the costs , difficulties , and the hazards .

[Marvin]

Now why doesnt it surprise me Rosco would rave about the Urea process :D

I agree with him completely though, if you want azides anhydrous hydrazine is not a logical intermediate. Ive read it doesnt attack glass much, but the hydrate does, so I'd follow Merck on that one.

I'm not sure if I missed kurtz's post acceidentally, but it might be becuase it took a while for a mod to authorize it. Either way I'd sure like to see any scanned versions of those references.

"Of all the Bizzaro ways to make hydrazine, you seem to have picked the least practical ones."

This made me laugh. Why is it with hydrazine the wierd and low yeilding ones are the most attractive looking yet the ones that are long, dull, well tested and OTC trivial we avoid like plauge victims.

I'm working on a a simpler way to sodium azide from OTCs that bypasses hydrazine entirley. More information when apropriate. For the time being going with a basic alcoholic extraction of a hydrazine salt sounds like a good process. There are some tricks with magnesium metal, producing the alkoxide that can remove water completely if needed for other experiments.

[Rosco Bodine]

The urea process was simply the method which appeared to be
most promising for a lab scale approach to producing usable yields
with economy , easily available precursors , and minimal equipment ,
while still being a relatively clean and safe process . I did look at
alternative methods , but the urea method became the clear preference
after all the factors were considered . The urea method works so
well that the synthesis should be confirmed and a technical writer
should do a proper writeup and have it added to the four volume Wiley
Organic Syntheses as an improvement over the older method , whenever
they next update their publication .

Azides were the principal reason for my interest in devising a good method
for lab scale production of hydrazine . And the first order of business
there was to devise a method for producing pure sodium azide directly
without any need for distillation of hydrazine . The freebasing and
methanol extraction of the hydrazine hydrate , followed by reaction in
the cold with isopropyl nitrite , satisfied the goal of producing pure
sodium azide in good yield by the most direct approach found to work .

The alternative Hodgkinson patent process looks to be so simple that
I tried to replicate that reported work , but even after literally two dozen
experiments using the same or slightly varying conditions from those
reported by Hodgkinson , there was ZERO success in producing azides
by Hodgkinsons method , which I quite frankly believe to be fraudulent .
I even tried some significant variations applying my own ideas of how
to troubleshoot and modify the reaction conditions to achieve the desired
results , but nothing I tried worked , even when extremely close control
of pH , temperature , reaction concentrations and mixing parameters were
applied , negative results became the predictable outcome .

On paper and in theory the reactions work beautifully , but in the
reaction vessels , everything else but what you expect should happen
was the rule for "Hodgkinson type" hydrazine sulfate / sodium nitrite
reaction scenarios . Anyone who can make such a reaction produce
azides , should declare how the matter is accomplished , and take a
bow for discovering and sharing the secret . This puzzle has already
stumped and thoroughly humiliated both Rosco and Philou , so Marvin
you are invited and welcome to solve this enigma of molecule crafting ,
and please teach us what we want to know :D

[kurtz]

May I get a little off the anhydrous part of the original post and more towards the alternative syntheses part?

Marvin, you may want to see scans of those articles, but I doubt that the Administration would want even a pittance of their bandwidth used for them. I read every one of them, and all seem impractical. Hydrazine or its salts were not actually isolated in any of them, determinations were spectral and sometimes chemical.

One article that did have isolation of the pure sulfate, JACS 55, 1968-1974 (1933), used NH3/.05mm tungsten filaments to produce 380 mg./kWh. These filaments were heated to 3000C.

It would be interesting to see if the Preparation of...'s in that book actually presented full experimental details. Something like what follows at the end of this post, for example of what I'm looking for. Especially of the older methods - I'd love to know exactly what's in all those old German and French articles that use hyponitrous acid/Na bisulfite/Zn/acetic acid, nitramide/Zn/H+, nitrourea, nitroguanidine, diazo- aldehyde ammonia or hexamine/Zn, Fe, Al, or Mg, and the original ethyl diazoacetate/NaOH/H+ route. All of these articles (at least 24) sit in the library mocking my 1 year of high school German. I've no idea just how practical these methods are if one happens to have these precursors.

I was able to find an English article, JCS 69, 1610-1620 (1896) that deals with the Na/Hg reduction of K nitrosulfate (NO, KOH, K2SO3). That's what they call it, I think its KSO3N(NO)OK. And I think that the Germans got this to work with alkaline Zn instead of the amalgam. Something similar in choice of reductants, acetone/NO/NaOH in EtOH. This may work with alkaline aluminum. Also found JACS 54, 1530-1538 (1932) which used methyl isopropyl ketone and ethyl nitrite, which I will paraphrase even though this is, um, off the anhydrous hydrazine process topic:

125 g methyl isopropyl ketone and 6.7 ml conc. HCl was kept at 45-55C as the theoretical amount (1.45 moles) of gaseous ethyl nitrite (OS X, 22) was added over 2 hrs. The product was put in the freezer and then cooled more with a freezing mixture. The crystals were washed with ether giving nearly pure bis- methyl nitrosoisopropyl ketone in 24% yield, 40g.

17.25 g (.15 mole) of this (finely ground) was slowly added to a stirred solution of 84.5 g SnCl2·2H2O (.375 mole) in 123 ml conc HCl. The temp was kept below 25C during addition, but was allowed to warm and stir until the reaction became homogenous, 5 hours. 190 ml H2O was added and methyl isopropyl ketone was distilled off. The Sn was precipitated with H2S. What liquid remained was evaporated nearly to dryness, and EtOH was added precipitating the hydrazine dihydrochloride. This was washed with ether giving a 40% yield of nearly pure N2H4·2HCl.

As impractical as this or the other methods above may be compared to urea or aq. ammonia, these are far better than the old methods in my earlier post. I wonder if any improvements have been made to the anhydrous processes, but not enough to buy the book.

meselfs- Of course you're right, you said not especially useful, not useless - I apologize. I will make up for it by looking up the Inorg Syn ref for it. However, there was no need for the industry lecture, I was simply stating an FYI fact.

OK - Inorganic Syntheses 1, 68-74 (Nitramide) does not fit meselfs request for an "easy" synthesis of nitramide, for most people here. It starts with urethane, H2SO4, ethyl nitrate, Et2O, and NH4OH to give ammonium nitrourethane (47-55% yield). This yields K nitrocarbamate on treatment with KOH/MeOH (65-80% yield). Finally, this is added to dilute H2SO4 to give nitramide (75-85%yield). I left a lot out, the authors give much detail and say that such detail is necessary. I don't think that anyone here wants nitramide that badly. For hydrazine, it hardly seems worth the trouble.

[Marvin]

meselfs,

"Would that mean they have chelating properties as well? "
Yes, that exactly.

"I don't think anhydrous ammonia is too much trouble, "
I do, its not meerly the low temperature, dry ice isnt that hard to find, its what happens if you run out....

Aq ammonia produces wet ammonia, which you can breathe in and it can cause short term diaphram paralysis. Ive had this (from an unlucky lungful following a spillage of 880) and its somewhat scarey, but I read that dry ammonia is much much worse. Pulmonary edaema territory.

N2(g) + 5H+(aq) + 4e- <——> N2H5+(aq)

This is only valid for the destruction of hydrazine, it doesnt imply you can make it.

"I don't think an ozonater would work since ozone's formation is more endothermic and since ozone is less sensitive in some ways."

Maybe I can convince you. Ozoniser is basically a very low density glow discharge, broken molecules, but without any thermal problems. Ozone forms by oxygen being broken up into O. radicals, I'm thinking hydrazine would form from NH2. radicals. Its possible that radical density is a critical factor though.

kurtz,

For me this thread is a patchwork and the intention it seems was only to make azides anyway. If the mods object it can always be merged with the existing hydrazine thread. If those articles are in easy reach I'd still like to see them, you could upload to the forum FTP, if they arnt dont bother the effort is better spent on things that will produce decent yeilds. Having spent so long in libraries looking up weird methods I have a slant in that direction. I recall one method that involved nitrosating hexamine and then reducing.

I'm fairly sure the nitrourea method will involve reduction to semicarbazide and Ive been wondering about the production of azides this way. What with the reduction it doesnt seem easier than the urea/hyperchlorite method but I'm still after a process for the final azide step. If hydrazine can by obtained fro semicarbazide thats also useful. There is a nitrourea to semicarbazide prep in detail on SM, goes via acetone semicarbazide though so it looks a little messy.

http://www.sciencemadness.org/talk/viewthread.php?tid=253

The Tungstun wire method is a possible OTC method, you can buy 2 mil wire at magic shops as one of the grades of 'invisible wire'. By my math that would be pretty close to 0.05mm. If its possible to freeze out anhydrous hydrazine it could be useful. I wonder how much ammonia it turns into N2 and H2 in the process. I'm also quite surprised actually the wire wasnt destroyed rather rapidly. Hot ammonia is really unfriendly to most metals. I read a really dull article on it once purely because it was next to a fantastic article in the same journal and I was bored.

Ok, I'm done with this post because its late and my first attempt was eaten by a power cut. Some days things are just uphill both ways.

[meselfs]

I do, its not meerly the low temperature, dry ice isnt that hard to find, its what happens if you run out....


No problem if you store it under pressure. A coke bottle will work surpisingly well.
Those bottles have a design pressure of around 200 psi. If propane at room temprature makes around 50 psi, then ammonia shouldn't be too difficult; and I've worked with propane before, it's not a great challenge.

I tried making some a few days ago via distillation under pressure, but the pressure caused the ammonia to dissolve in large amounts into the reaction jar. I tried to put as little water as possible but that happened anyway. To solve this I'll probably have to get my hands on either dry ice or a pump...
Maybe I can convince you. Ozoniser is basically a very low density glow discharge, broken molecules, but without any thermal problems. Ozone forms by oxygen being broken up into O. radicals, I'm thinking hydrazine would form from NH2. radicals. Its possible that radical density is a critical factor though.

Hmnn... I just might be convinced.

I recall one method that involved nitrosating hexamine and then reducing.

An explosive called CTMTNA is bassically RDX except nitroso instead of nitro. It's very easy to make but generally has 40% yield. Reduction would probably be aqueos so I imagine that this is impractical, since the yield would be better with the good old urea methode.

I just had a thought on the NH3 + NH2Cl method. NH2Cl is one of the intermediate chems involved in the synthesis of NCl3, which doesn't react to form NHCl2 and NCl3 at a certain pH. Is there any chance of synthesizing it by passing Cl2 into an ammonia solution at a carefully-controlled pH?

Sorry for missing this...
I read somewhere that the reaction must be dry, although the reaction between ammonia and chloramine must be in the jello solution.

It would be interesting to see if the Preparation of...'s in that book actually presented full experimental details. Something like what follows at the end of this post, for example of what I'm looking for.

It'd better... the whole book is over 2000 pages long.

However, there was no need for the industry lecture

Sorry :D

[meselfs]

I read "Comprehensive Inorganic Chemistry" at a newfound library. Some items of interest:

Urea -----Ni, 60-7 C-----> CO + Hydrazine

Now that seems exceedingly ideal. What's the catch? If it takes weeks to proceed, that's fine by me... I heard that factories never use slow processes so maybe that's why it's never used (I'm such a stupid optimist).


Also:
NO2 + NH3 ----> HNO2 + NH2

I've read that NH2 readily dimerizes into hydrazine.
This method isn't very attractive to me, since I'm pretty sure the HNO2 will cause a mess, to say the least.


But the first method... any thoughts? That 60 - 70 C is way below the melting point, so how would the urea contact the Ni? Aq soln, maybe (heaven forbid!)?

[meselfs]

I read "Comprehensive Inorganic Chemistry" at a newfound library. Some items of interest:

Urea -----Ni, 60-7 C-----> CO + Hydrazine

Now that seems exceedingly ideal. What's the catch? If it takes weeks to proceed, that's fine by me... I heard that factories never use slow processes so maybe that's why it's never used (I'm such a stupid optimist).


Also:
NO2 + NH3 ----> HNO2 + NH2

I've read that NH2 readily dimerizes into hydrazine.
This method isn't very attractive to me, since I'm pretty sure the HNO2 will cause a mess, to say the least.


But the first method... any thoughts? That 60 - 70 C is way below the melting point, so how would the urea contact the Ni? Aq soln, maybe (heaven forbid!)?

[meselfs]

I read "Comprehensive Inorganic Chemistry" at a newfound library. Some items of interest:

Urea -----Ni, 60-7 C-----> CO + Hydrazine

Now that seems exceedingly ideal. What's the catch? If it takes weeks to proceed, that's fine by me... I heard that factories never use slow processes so maybe that's why it's never used (I'm such a stupid optimist).


Also:
NO2 + NH3 ----> HNO2 + NH2

I've read that NH2 readily dimerizes into hydrazine.
This method isn't very attractive to me, since I'm pretty sure the HNO2 will cause a mess, to say the least.


But the first method... any thoughts? That 60 - 70 C is way below the melting point, so how would the urea contact the Ni? Aq soln, maybe (heaven forbid!)?

[megalomania]

The procedure is not exactly new since it has been around for 50 years... Ullmann's does not mention it, so that should tell you right there it is not "economicially" viable. I happen to have a patent in my collection, let's see... Ahh yes, US patent 2,717,201 the Production of Hydrazine details this very procedure.

The jist of the reaction is that you mix powdered urea with powdered nickel at around 70 C and stir. The hydrazine along with carbon monoxide are emmitted and should be collected. The reaction can also use iron as a catalyst, although the temperature should be nearer the melting point of urea then, around 130 C. In fact at around 60-70 C there may be very little hydrazine given off. You can end up with a slurry of hydrazine and unreacted urea with nickel.

Sounds too good to be true... Naturally this procedure is probably dangerous and nickel carbonyl (the byproduct of this reaction) is rather toxic. Merck also says it explodes at 60 C, but I would hope it is diluted enough in the reaction for it to just decompose as it is formed.

[megalomania]

The procedure is not exactly new since it has been around for 50 years... Ullmann's does not mention it, so that should tell you right there it is not "economicially" viable. I happen to have a patent in my collection, let's see... Ahh yes, US patent 2,717,201 the Production of Hydrazine details this very procedure.

The jist of the reaction is that you mix powdered urea with powdered nickel at around 70 C and stir. The hydrazine along with carbon monoxide are emmitted and should be collected. The reaction can also use iron as a catalyst, although the temperature should be nearer the melting point of urea then, around 130 C. In fact at around 60-70 C there may be very little hydrazine given off. You can end up with a slurry of hydrazine and unreacted urea with nickel.

Sounds too good to be true... Naturally this procedure is probably dangerous and nickel carbonyl (the byproduct of this reaction) is rather toxic. Merck also says it explodes at 60 C, but I would hope it is diluted enough in the reaction for it to just decompose as it is formed.

[megalomania]

The procedure is not exactly new since it has been around for 50 years... Ullmann's does not mention it, so that should tell you right there it is not "economicially" viable. I happen to have a patent in my collection, let's see... Ahh yes, US patent 2,717,201 the Production of Hydrazine details this very procedure.

The jist of the reaction is that you mix powdered urea with powdered nickel at around 70 C and stir. The hydrazine along with carbon monoxide are emmitted and should be collected. The reaction can also use iron as a catalyst, although the temperature should be nearer the melting point of urea then, around 130 C. In fact at around 60-70 C there may be very little hydrazine given off. You can end up with a slurry of hydrazine and unreacted urea with nickel.

Sounds too good to be true... Naturally this procedure is probably dangerous and nickel carbonyl (the byproduct of this reaction) is rather toxic. Merck also says it explodes at 60 C, but I would hope it is diluted enough in the reaction for it to just decompose as it is formed.

[cutefix]

The procedure is not exactly new since it has been around for 50 years... Ullmann's does not mention it, so that should tell you right there it is not "economicially" viable. I happen to have a patent in my collection, let's see... Ahh yes, US patent 2,717,201 the Production of Hydrazine details this very procedure.

The jist of the reaction is that you mix powdered urea with powdered nickel at around 70 C and stir. The hydrazine along with carbon monoxide are emmitted and should be collected. The reaction can also use iron as a catalyst, although the temperature should be nearer the melting point of urea then, around 130 C. In fact at around 60-70 C there may be very little hydrazine given off. You can end up with a slurry of hydrazine and unreacted urea with nickel.

Sounds too good to be true... Naturally this procedure is probably dangerous and nickel carbonyl (the byproduct of this reaction) i.

The main concern there with such form of vapor phase synthesis...is it had many toxic products emanated.
I was wondering who among the forum members would give it a try? :cool:
Besides Semicarbazide is one by product which can be converted to hydrochloride and then will become the base ingredient for the synthesis of nitrotriazolone, a powerful but insenstive high explosive which is likely to replace TATB.
Meanwhile the standard form of hydrazine synthesis was proposed by german chemist Freidrich Raschig in the US patent 910858 titled : Synthesis of hydrazine. It is simple and can be made with OtC ingredient but unfortunately will end in hydrazine suflate which is difficult to extract the anhydrous hydrazine :(

[cutefix]

The procedure is not exactly new since it has been around for 50 years... Ullmann's does not mention it, so that should tell you right there it is not "economicially" viable. I happen to have a patent in my collection, let's see... Ahh yes, US patent 2,717,201 the Production of Hydrazine details this very procedure.

The jist of the reaction is that you mix powdered urea with powdered nickel at around 70 C and stir. The hydrazine along with carbon monoxide are emmitted and should be collected. The reaction can also use iron as a catalyst, although the temperature should be nearer the melting point of urea then, around 130 C. In fact at around 60-70 C there may be very little hydrazine given off. You can end up with a slurry of hydrazine and unreacted urea with nickel.

Sounds too good to be true... Naturally this procedure is probably dangerous and nickel carbonyl (the byproduct of this reaction) i.

The main concern there with such form of vapor phase synthesis...is it had many toxic products emanated.
I was wondering who among the forum members would give it a try? :cool:
Besides Semicarbazide is one by product which can be converted to hydrochloride and then will become the base ingredient for the synthesis of nitrotriazolone, a powerful but insenstive high explosive which is likely to replace TATB.
Meanwhile the standard form of hydrazine synthesis was proposed by german chemist Freidrich Raschig in the US patent 910858 titled : Synthesis of hydrazine. It is simple and can be made with OtC ingredient but unfortunately will end in hydrazine suflate which is difficult to extract the anhydrous hydrazine :(

[cutefix]

The procedure is not exactly new since it has been around for 50 years... Ullmann's does not mention it, so that should tell you right there it is not "economicially" viable. I happen to have a patent in my collection, let's see... Ahh yes, US patent 2,717,201 the Production of Hydrazine details this very procedure.

The jist of the reaction is that you mix powdered urea with powdered nickel at around 70 C and stir. The hydrazine along with carbon monoxide are emmitted and should be collected. The reaction can also use iron as a catalyst, although the temperature should be nearer the melting point of urea then, around 130 C. In fact at around 60-70 C there may be very little hydrazine given off. You can end up with a slurry of hydrazine and unreacted urea with nickel.

Sounds too good to be true... Naturally this procedure is probably dangerous and nickel carbonyl (the byproduct of this reaction) i.

The main concern there with such form of vapor phase synthesis...is it had many toxic products emanated.
I was wondering who among the forum members would give it a try? :cool:
Besides Semicarbazide is one by product which can be converted to hydrochloride and then will become the base ingredient for the synthesis of nitrotriazolone, a powerful but insenstive high explosive which is likely to replace TATB.
Meanwhile the standard form of hydrazine synthesis was proposed by german chemist Freidrich Raschig in the US patent 910858 titled : Synthesis of hydrazine. It is simple and can be made with OtC ingredient but unfortunately will end in hydrazine suflate which is difficult to extract the anhydrous hydrazine :(

[meselfs]

I'd love to know why Kellog needs hydrazine (they own the patent) :-S

The carbonyl should decompose as soon as it forms, even in the absence of oxygen. I don't think there's an explosion risk.

I got an idea: what if this is done in boiling methanol? Urea will dissolve in it (1:6 at STP), and the methonal boils at an ideal temperature: 65 C. Hot methanol shouldn't react with hydrazine...
...right?

Just reflux the mix a few hours, I don't see a problem, except the possibility that the reaction is incomplete, as mega hinted. Still, I think a liquid medium is a good idea, and methanol is fine choice.

[meselfs]

I'd love to know why Kellog needs hydrazine (they own the patent) :-S

The carbonyl should decompose as soon as it forms, even in the absence of oxygen. I don't think there's an explosion risk.

I got an idea: what if this is done in boiling methanol? Urea will dissolve in it (1:6 at STP), and the methonal boils at an ideal temperature: 65 C. Hot methanol shouldn't react with hydrazine...
...right?

Just reflux the mix a few hours, I don't see a problem, except the possibility that the reaction is incomplete, as mega hinted. Still, I think a liquid medium is a good idea, and methanol is fine choice.

[meselfs]

I'd love to know why Kellog needs hydrazine (they own the patent) :-S

The carbonyl should decompose as soon as it forms, even in the absence of oxygen. I don't think there's an explosion risk.

I got an idea: what if this is done in boiling methanol? Urea will dissolve in it (1:6 at STP), and the methonal boils at an ideal temperature: 65 C. Hot methanol shouldn't react with hydrazine...
...right?

Just reflux the mix a few hours, I don't see a problem, except the possibility that the reaction is incomplete, as mega hinted. Still, I think a liquid medium is a good idea, and methanol is fine choice.

[Marvin]

This came up a year or so ago at science madness, it was tried by BromicAcid and produced no distillate at all well beyond the temperature mentioned in the patent. He used nickel powder produced by thermal decomposition of the oxalate too, which should have been the most active. Its a little disturbing to think how many patents simply arn't true. Maybe important details are missing or maybe its based on the expectation of certain reactions of hydrazine and metal carbonyls going backwards under the same conditions they go forwards.

I cant find the reference where hydrazine and a metal carbonyl go to urea and I wonder if I'm mistaken on that, but I can find one where iron carbonyl and hydrazine go to 'a complex mixture of semicarbazide, iron carbonyl and hydrazine'.

The relavent thread is currently located,
http://67.15.145.24/~sciencem/talk/viewthread.php?tid=1128

Interesting idea to try boiling methanol but it could react with the urea producing ammonia and a urethane.

[Marvin]

This came up a year or so ago at science madness, it was tried by BromicAcid and produced no distillate at all well beyond the temperature mentioned in the patent. He used nickel powder produced by thermal decomposition of the oxalate too, which should have been the most active. Its a little disturbing to think how many patents simply arn't true. Maybe important details are missing or maybe its based on the expectation of certain reactions of hydrazine and metal carbonyls going backwards under the same conditions they go forwards.

I cant find the reference where hydrazine and a metal carbonyl go to urea and I wonder if I'm mistaken on that, but I can find one where iron carbonyl and hydrazine go to 'a complex mixture of semicarbazide, iron carbonyl and hydrazine'.

The relavent thread is currently located,
http://67.15.145.24/~sciencem/talk/viewthread.php?tid=1128

Interesting idea to try boiling methanol but it could react with the urea producing ammonia and a urethane.

[Marvin]

This came up a year or so ago at science madness, it was tried by BromicAcid and produced no distillate at all well beyond the temperature mentioned in the patent. He used nickel powder produced by thermal decomposition of the oxalate too, which should have been the most active. Its a little disturbing to think how many patents simply arn't true. Maybe important details are missing or maybe its based on the expectation of certain reactions of hydrazine and metal carbonyls going backwards under the same conditions they go forwards.

I cant find the reference where hydrazine and a metal carbonyl go to urea and I wonder if I'm mistaken on that, but I can find one where iron carbonyl and hydrazine go to 'a complex mixture of semicarbazide, iron carbonyl and hydrazine'.

The relavent thread is currently located,
http://67.15.145.24/~sciencem/talk/viewthread.php?tid=1128

Interesting idea to try boiling methanol but it could react with the urea producing ammonia and a urethane.

[meselfs]

Thanks alot, Marvin. Methanol seems to fit all of the points needed in that thread.

Here's how I'd do it:

Mix urea and methanol, 10 g or so methanol to 1 g urea (beyond STP saturation). Put this in a beaker, not a flask. Add some chunks of nickel, free of copper. Put all this in a convinient location.
Setup another beaker with boiling water, have this placed not too close to the first beaker, since hydrazine's flash point is near 50 C.
Setup a steel pipe, going first into the boiling water, then into the methanol beaker. In the methanol beaker, the pipe should have lots of tiny holes in it, as to aerate the mix.
Pass air dessicated with CaCl2 through the pipe.

If that fails, I'd then try:
Make or obtain a refulxing setup, reflux the appropriate mix for a while with air entering the mix through a steel tube.

In any case:
If the nickel doesn't dissolve, simply spoon it out & boil off the methanol. If it does, you'll probably have to do a nerve wrecking distillation.


Some things to note:

Methanol boils around 65 C and dissolves urea in 6:1.

Do not add H2S (suggested in that thread)!!! It's a fact that urea can be made by combination of ammonia and CO in methanol in the presence of sulfur...

Metal ions aren't a huge problem, in the Raschig method they are problematic only because the nascent chlorine/oxygen will attack the hydrazine, catalyzed by the ions. Since in this process doesn't rely on oxygen/chlorine attacking anything, the metal ions shouldn't matter. So, don't add any chelate.

If there's a reaction between the steel pipe and hot soln, use PTFE.

Merck says that methanol and hydrazine are miscible, which must indicate that they don't react. I really hope this is still true when the methanol boils.




My question, and this may sound really, really silly to some of you veterans: will the hot air (~65 C) react with the hydrazine? The point is for it to react with the carbonyl. Such reaction is basically guarunteed.


If several hours of unattended refulxing produce > 20% yeild, I think this'd be well worth it.

[meselfs]

Thanks alot, Marvin. Methanol seems to fit all of the points needed in that thread.

Here's how I'd do it:

Mix urea and methanol, 10 g or so methanol to 1 g urea (beyond STP saturation). Put this in a beaker, not a flask. Add some chunks of nickel, free of copper. Put all this in a convinient location.
Setup another beaker with boiling water, have this placed not too close to the first beaker, since hydrazine's flash point is near 50 C.
Setup a steel pipe, going first into the boiling water, then into the methanol beaker. In the methanol beaker, the pipe should have lots of tiny holes in it, as to aerate the mix.
Pass air dessicated with CaCl2 through the pipe.

If that fails, I'd then try:
Make or obtain a refulxing setup, reflux the appropriate mix for a while with air entering the mix through a steel tube.

In any case:
If the nickel doesn't dissolve, simply spoon it out & boil off the methanol. If it does, you'll probably have to do a nerve wrecking distillation.


Some things to note:

Methanol boils around 65 C and dissolves urea in 6:1.

Do not add H2S (suggested in that thread)!!! It's a fact that urea can be made by combination of ammonia and CO in methanol in the presence of sulfur...

Metal ions aren't a huge problem, in the Raschig method they are problematic only because the nascent chlorine/oxygen will attack the hydrazine, catalyzed by the ions. Since in this process doesn't rely on oxygen/chlorine attacking anything, the metal ions shouldn't matter. So, don't add any chelate.

If there's a reaction between the steel pipe and hot soln, use PTFE.

Merck says that methanol and hydrazine are miscible, which must indicate that they don't react. I really hope this is still true when the methanol boils.




My question, and this may sound really, really silly to some of you veterans: will the hot air (~65 C) react with the hydrazine? The point is for it to react with the carbonyl. Such reaction is basically guarunteed.


If several hours of unattended refulxing produce > 20% yeild, I think this'd be well worth it.

[meselfs]

Thanks alot, Marvin. Methanol seems to fit all of the points needed in that thread.

Here's how I'd do it:

Mix urea and methanol, 10 g or so methanol to 1 g urea (beyond STP saturation). Put this in a beaker, not a flask. Add some chunks of nickel, free of copper. Put all this in a convinient location.
Setup another beaker with boiling water, have this placed not too close to the first beaker, since hydrazine's flash point is near 50 C.
Setup a steel pipe, going first into the boiling water, then into the methanol beaker. In the methanol beaker, the pipe should have lots of tiny holes in it, as to aerate the mix.
Pass air dessicated with CaCl2 through the pipe.

If that fails, I'd then try:
Make or obtain a refulxing setup, reflux the appropriate mix for a while with air entering the mix through a steel tube.

In any case:
If the nickel doesn't dissolve, simply spoon it out & boil off the methanol. If it does, you'll probably have to do a nerve wrecking distillation.


Some things to note:

Methanol boils around 65 C and dissolves urea in 6:1.

Do not add H2S (suggested in that thread)!!! It's a fact that urea can be made by combination of ammonia and CO in methanol in the presence of sulfur...

Metal ions aren't a huge problem, in the Raschig method they are problematic only because the nascent chlorine/oxygen will attack the hydrazine, catalyzed by the ions. Since in this process doesn't rely on oxygen/chlorine attacking anything, the metal ions shouldn't matter. So, don't add any chelate.

If there's a reaction between the steel pipe and hot soln, use PTFE.

Merck says that methanol and hydrazine are miscible, which must indicate that they don't react. I really hope this is still true when the methanol boils.




My question, and this may sound really, really silly to some of you veterans: will the hot air (~65 C) react with the hydrazine? The point is for it to react with the carbonyl. Such reaction is basically guarunteed.


If several hours of unattended refulxing produce > 20% yeild, I think this'd be well worth it.

[Rosco Bodine]

My question, and this may sound really, really silly to some of you veterans: will the hot air (~65 C) react with the hydrazine?

Hydrazine is a highly air sensitive , oxygen sensitive material , and it is destroyed
rapidly by exposure to air , or even to dissolved air or dissolved oxygen in water
or other liquids . Hydrazine is an effective " getter " for oxygen and it is for that reason that hydrazine is added to the boiler water in steam heating systems .
A certain level of hydrazine in the water used in a closed loop system will prevent
corrosion of the pipes and the boiler , by reacting with and removing any
dissolved oxygen .

[Rosco Bodine]

My question, and this may sound really, really silly to some of you veterans: will the hot air (~65 C) react with the hydrazine?

Hydrazine is a highly air sensitive , oxygen sensitive material , and it is destroyed
rapidly by exposure to air , or even to dissolved air or dissolved oxygen in water
or other liquids . Hydrazine is an effective " getter " for oxygen and it is for that reason that hydrazine is added to the boiler water in steam heating systems .
A certain level of hydrazine in the water used in a closed loop system will prevent
corrosion of the pipes and the boiler , by reacting with and removing any
dissolved oxygen .

[Rosco Bodine]

My question, and this may sound really, really silly to some of you veterans: will the hot air (~65 C) react with the hydrazine?

Hydrazine is a highly air sensitive , oxygen sensitive material , and it is destroyed
rapidly by exposure to air , or even to dissolved air or dissolved oxygen in water
or other liquids . Hydrazine is an effective " getter " for oxygen and it is for that reason that hydrazine is added to the boiler water in steam heating systems .
A certain level of hydrazine in the water used in a closed loop system will prevent
corrosion of the pipes and the boiler , by reacting with and removing any
dissolved oxygen .