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chloric1
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Search
I am pretty sure this method was already dscussed. Try searching the forum and I am sure you will find something. I remember writing about mekazine.
I cannot remember the patent number but the ketazines can be produced from ketones, ammonia and hypochlorites. THis should be easier for the home
chemist. You just mix 2 moles of ammonia fir every mole of hypochlorite to form your chloramine(preferably at 0C) and add this solution to a well
stirred mixture of MEK and concentrated ammonia. Gelatine is optional. Ultimately you would use about 10 to 15: 1 ratio for ammonia to hypochlorite.
The ammonia to ketone should be more than a 4:1 ratio.
I will let you know if and when I find the patent.
P.S. the ketazines hydrolysis in water is under 10 atmospheres . When strong acids
are used, it happens at standard pressure and only a little heat is required.
Fellow molecular manipulator
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jester
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has somebody posted a link for hydrazine and its derivatives yet
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stricnine
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Hi there!
Hydrazine was used by the German Luftwaffe to power the Messerschmitt Me 163, an interceptor (II WW!) powered by a hydrazine-hydrogen peroxide rocket
(clearly based upon the fact that it reacts readily with oxygen). The thing reached over 1000Km/h in 1944/45! Perhaps this could start a new thread in
the energetic reactions forum!
Cheers
Stricnine
I am getting old. I used to push it aside with one hand... now I need both!
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verode
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also urea and hypobromite or hypochlorite you get (hoffman) the hydrazine
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Theoretic
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Me 163 used hydrazine hydrate + methanol as fuel.
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Sauron
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The Org.Syn. procedures for hydrazine, hydrazine hydrate, hydrazine suphate, and neat anhydrous hydrazine have stodd the test of time and are
available freely online.
Hydrazine in any form is a nasty beast so I hope you have SCBA or at least a good hood. Where I am one can buy the sulphate and hydrate freely and in
bulk. Generally these are regarded as proven human carcinogens (which are few and far between) just in case you were not aware.
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Rosco Bodine
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| Quote: | Originally posted by Sauron
The Org.Syn. procedures for hydrazine, hydrazine hydrate, hydrazine suphate, and neat anhydrous hydrazine have stodd the test of time and are
available freely online. |
The method described in Wiley for hydrazine sulfate is in every way inferior and primitive compared to the two alternative methods described in this
forum for synthesis from urea .
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Sauron
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I believe the Hoffman is best done with hypohalite freshly prepared in situ because off the shelf solutions always contain appreciate amounts of
chlorate ion.
I tried this rxn a couple of times on pthalimide (trying to obtain anthanilic acid) but all I got was a gray-black gunky mess.
If memory serves doesn't this rxn proceed through the isocyanate?
[Edited on 27-12-2006 by Sauron]
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Rosco Bodine
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Read this whole thread . There are other related threads
and plenty of patent references cited .
I personally developed a lab scale optimized adaptation of the Merck patent process ( GB392845 ) from many experiments , which have been confirmed by
others .
http://sciencemadness.org/talk/viewthread.php?tid=757#pid656...
Going beyond that , the chlorourea method has been described earlier in this thread . The hydrazine sulfate
from both methods has been used to produce sodium azide , and also hydrazoic acid IIRC , via reaction with H2O2 ,
http://sciencemadness.org/talk/viewthread.php?tid=1987&p...
as well as having structure confirmed instrumentally by FTIR spectroscopy by ordenblitz here in this thread .
We probably should accumulate all the hydrazine / azide related experiments into one ScienceMadness " correlative volume " and put it in the Forum
Library as well as send it to Wiley as an addendum / update to their antiquated
and obsolete method .
[Edited on 27-12-2006 by Rosco Bodine]
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S.C. Wack
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Sauron seems to have deleted where he doubted making hydrazine from urea and hypochlorite, which makes my looking up DE164755, US1959503 (the above GB
patent), DE729105, and DE735321 seem pointless.
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Sauron
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I will happily look at those patents.
I deleted a hasty and excessive skepticism about a topic off my patch.
Here, hydrazine hydrate and sulphate are reradily purchaseable in both lab and bulk qty. No one seems overly worried about its toxicity or about
damnfools making astrolite. My main supply jouse has 20 L pails of the hydrate at 50% if I recall. I doubt it is expensive. I rarely have a use for it
as I am not making bootleg Viagra and its former prominence in peptide work is passe.
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Rosco Bodine
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Hydrazine and a few other " essential reagents " have been topics of great interest for the experimenters who
do not wish to purchase such chemicals for whatever reasons , or who simply prefer to make their own reagents from the most basic precursors .
Sometimes this is an academic exercise and revisiting of the work of early researchers experimentation , out of curiosity about
what may have been missed or gone unreported or unrecognized in significance , and also looking for what is very good knowledge but has become "lost
art" in the present texts .
When you want to learn about grandpas practical
synthetic methods ....you have to talk to grandpa , or
read his journals and patents and try to glean from those what may still be very useful information today .
It never hurts either for the younger folks to understand that some *very* smart men lived long long ago . And those ancients figured out a few things
which shouldn't need to be rediscovered in historical obscurity . Yet older work often seems to be rediscovered and reinvented and revalued in some
new way when the technology and materials of the present is applicable in some beneficial way to methods and knowledge of the past . It can be
properly humbling to hear an appropriate "I told you so"
from pages written fifty or a hundred years or more ago  ....written in answer
to a question it was known
in advance that someone was going to sooner or later be asking and find already answered at least in part
This is what puts the " re " in re-search you know ,
often travelling a path travelled before , but having a
different pair of eyes observing the scenery and
seeing if more can be seen by this traveller than
was recognized by the one(s) who went before ,
and perhaps to add another cumulative list of
footnotes to mark the point of what more is known now ,
than what was the assembled knowledge before .
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Sauron
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"If we see far it is merely because we are standing on the shoulders of giants."
A scientist paying homage to those who went before. I forget who it was who said it. It's an immortal line.
And I hate to admit it but I am long since old enough to be a grandpa.
[Edited on 27-12-2006 by Sauron]
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Rosco Bodine
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Greetings to a fellow dinosaur
For I am a grandpa too .....
Just wish I knew when I was young what I know now ,
for life would have been much more fun and profitable
and at a time when I was still young and healthy enough to enjoy it .
By the time you are old enough to know the best of what life is all about .....the best of life is already behind you ,
and this is a cruel irony .
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Sauron
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Ain't it the god-awful truth? Like General Sternwood in "The Big Sleep" I'm a very dull survival of a very gaudy life. Now reduced to enjoying my
vices only by proxy.
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unionised
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According to some source I read this "If we see far it is merely because we are standing on the shoulders of giants." was a dig by Newton at his
contemporary Hooke who was short. but then again, maybe not.
http://en.wikipedia.org/wiki/Robert_Hooke
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joe69cool
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hydrazine precautions.
I recently read that anhydrous hydrazine can be prepared from hydrazine sulfate by treatment with caustic methanol. I'm curious, would it be safe to
distill off the methanol or would that lead to an ugly explosion (I think it would)? I realise its not something to be done in the home lab, but I'm
curious never the less. Thanks, and pardon my ignorance.
[Edited on 3-3-2007 by joe69cool]
\"Why oh why didn\'t I take the blue pill?\"
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BromicAcid
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Not really anhydrous...
N<sub>2</sub>H<sub>4</sub>* H<sub>2</sub>SO<sub>4</sub> + 2NaOH<sub>methanol</sub> --->
N<sub>2</sub>H<sub>4</sub> + Na<sub>2</sub>SO<sub>4</sub> +
<b>2H<sub>2</sub>O</b>
I have done this prep before using potassium hydroxide dissolved in methanol. It goes well. But after filtering off the potassium sulfate and
distilling off the methanol you are still left with hydrated hydrazine in the end.
[Edited on 3/3/2007 by BromicAcid]
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Furch
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Try this and you'll rid the hydrated hydrazine:
2 MeONa + N2H4*H2SO4 -methanol-> N2H4 + 2 MeOH + Na2SO4
Sodium might be a little too expensive for the cause, though...
\"Those who say do not know, those who know do not say.\" -Lao Tzu
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DeAdFX
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Is it possible to use Urea in place of ammonia in the keatazine process? Something tells me that Urea and acetone aren't going to react to form
keatazine in any useful amount.
I was thinking that I could mix urea, acetone, and water and reflux for a few hours. The water would be for the hydrolsis of urea --> 2NH3 + CO2.
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not_important
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Urea doesn't hydrolise that quickly with catalysts. You need to get above 60 C in plain water to see much happening, and it still is fairly slow.
Given the boiling point of acetone the rate of hydrolysis is going to be real slow.
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garage chemist
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I have once again started experimentation concerning the preparation of hydrazine.
I have chosen to further develop the chlorourea process instead of any other processes, which use either materials with very limited shelf-life and
therefore unknown exact concentration (NaOCl over 5%) or have not been found to work on a small scale (ketazine process).
I have found that when chlorinating urea in aqueous solution, the solution turns green and slowly gives off colorless gas when 1 mol chlorine is used
for 1,5 mol urea, and foams like beer when poured or shaken- clearly signs of decomposition. It seems necessary to use not more than 1 mol chlorine
per 2 mol urea, as the solution does not turn green until shortly before all chlorine has been passed in (with 1mol Cl2/1,5mol urea).
I used a 50% aqueous solution of urea for the chlorination.
The chlorourea solution has been introduced into 50% NaOH solution with cooling and very vigorous stirring. A dense white fog is produced, and some
gas.
I have done two batches, each with 0,5mol Cl2/0,75mol urea and one using 1,5mol NaOH and one using 1,125mol NaOH, in order to find out if using less
NaOH affects yield a lot, since saving NaOH also saves a lot of acid in the neutralization.
The alkaline solution obtained by combining the chlorourea solution from 50% urea in water and 50% NaOH solution was slowly heated to boiling until
every green color had vanished.
The resulting solution was so concentrated that a substantial amount of NaCl crystallized out, more of it on cooling (The solubility of NaCl in this
mixed alkaline solution seems to be temperature dependent, unlike solutions of NaCl in water- or the precipitate contains another salt, like sodium
carbonate, which is another byproduct).
This would make it possible to directly distill a dilute hydrazine hydrate solution (its only ca. 250ml of solution for a 0,5 mol Cl2 batch, with
theoretical yield of 65g hydrazine sulfate!) without acidification. This would be an extremely favorable way of isolating the hydrazine, as
neutralization of the distillate with H2SO4 would provide the stable and easily stored sulfate in quantitative yield, as opposed to direct addition of
H2SO4 to the previously neutralized (with HCl) reaction mix, which leaves some of the product in solution due to its considerable solubility even at
0°C.
I have not tried this direct distillation of hydrazine hydrate from the reaction. If the two batches give encouraging yields of the sulfate, this will
be my next experiment.
[Edited on 14-4-2007 by garage chemist]
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garage chemist
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The yields of the chlorourea batches were terrible, totally useless.
First one gave ca. 15g, second one maybe 5g. I abandoned the chlorourea method for me, primarily because the chlorourea is unstable and a huge excess
of urea over chlorine has to be used, among other reasons.
-------------------------------
Today I have prepared the first batch of hydrazine sulfate using 70% Calcium hypochlorite (HTH pool chlorine) as the hypochlorite source.
I used 51,1g HTH, which I reacted with 37,8g Na2CO3, both as solutions, in the way I described in this thread:
http://www.sciencemadness.org/talk/viewthread.php?tid=8504
190ml of 15% NaOCl were obtained, corresponding to 0,45mol of NaOCl, a 90% yield in regard to HTH.
The rest of the synthesis was analogous to Mr. Anonymous' method for hydrazine sulfate, with some changes implemented by me.
I noticed that the solid NaOH dissolved extremely slowly in the 15% NaOCl when it was cold, and only started to dissolve with any noticeable speed as
the temperature went above 10°C. But then the temperature did not rise above 20°C after the portion of NaOH had dissolved, so there was no problem.
I added the NaOH in two portions of 22,5g each (with cooling between additions to 8°C), for a total of 45g NaOH with the 0,45 mol NaOCl.
The Improvement:
The 15% NaOCl was not chilled in the freezer, the fridge with 8°C did perfectly fine. With the NaOH added in two portions, the temperature will not
go above 20°C.
The same goes for the original HS synthesis when 10% NaOCl pool chlorinator is used!
If the NaOCl is chilled in the freezer instead of the fridge, the
NaOCl will simply warm up by itself to 10°C before the NaOH starts to dissolve. So not cooling below 0°C makes the process both easier and faster.
The NaOH stabilizes the NaOCl, so that 20°C can be tolerated for a short period of time if the NaOCl is chilled immediately after again.
After all NaOH had been dissolved, the NaOCl was chilled in the freezer to below 0°C, urea (34,1g) and gelatin (0,56g) were dissolved together in
40ml warm water and the instructions of Mr. Anonymous were followed until the end.
The foam rose to 1000ml from the ca. 250ml of solution.
The reaction became extremely hot by itself after the foam was produced. It subsided again quickly after.
Slowly heated to boiling until colorless, cooled, neutralized with 120ml 31% HCl and precipitated with 34ml conc H2SO4 (previously diluted with its
own volume of water).
The batch is currently cooling. A lot of HS was already precipitating after the H2SO4 had been added, despite the solution still being hot. I heated
until all had been dissolved, and then slowly left it cool in order to produce larger crystals. This works extremely well, as I can already see.
[Edited on 19-5-2007 by garage chemist]
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Rosco Bodine
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some reference tables
Here is a handy reference table for density and concentration of bleach along with some other general information .
Another idea sort of came to me regarding a possible usefulness of TCCA , which might produce calcium cyanurate
as an insoluble byproduct , which might later be useful for
a pyrolytic decomposition to calcium cyanamide . I haven't really written anything down as an equation to see if it
looks like it would work in a scheme for sodium hypochlorite .
There are perhaps a couple of different ways to go about it ,
so that you end up with a salt and sodium hypochlorite (bleach solution) as the supernatant , with a precipitate of
calcium cyanurate as a useful byproduct .
I'm thinking maybe calcium chloride together with sodium hydroxide and TCCA in some sequence or stirred and digested together for a couple of hours .
Or perhaps
hydrated lime and sodium carbonate or bicarbonate plus TCCA might work , with a gradual titration with HCl as it proceeds . I'm not really sure what
are the chances of
something like this working , but it would provide an interesting synthetic route eventually to tetrazoles and friends . So it may be a brainstorm or
a brainfart , depending
on whether it would work out ....but I couldn't help but grin a little when the idea occurred to me , as it would be pretty slick if it did work .
[Edited on 20-5-2007 by Rosco Bodine]
Attachment: bleach.pdf (80kB)
This file has been downloaded 2002 times
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garage chemist
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It worked awesome, I got 34,45g hydrazine sulfate from 51,1g 70% HTH on the first try!
Thats a 59% yield based on the sodium hypochlorite obtained as the intermediate. And that with incorrect stochiometry, as I now found out (I used too
much urea and too much NaOH), and rather small batch size.
The yield may become even better when using a larger batch size and correct stochiometry!
This method of generating a 15% NaOCl, low-NaCl solution from calcium hypochlorite and Na2CO3 is clearly a very good method for running the
hydrazine-producing reaction in as concentrated a solution as possible.
Now it is no longer necessary to use liquid pool chlorinator as the raw material. The use of calcium hypochlorite as raw material has been proven to
be an excellent substitute, with almost as good yields.
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