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Formatik
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I tried out neutralization with sodium bisulfate using theoretical amounts and keeping the Na2SO4 just soluble with minimal water. This method looked
promising, especially since the reaction between dilute H2SO4 and moderate aq. N2H4 is extremely violent (a lot worse than water and conc. H2SO4). But
the yield I got was very low. I think compared to H2SO4, it is still not worth it because of great yield loss.
Here's what was done: 10.0g 35% N2H4 was added to a clear solution of 27.6g 95% NaHSO4 in 70mL of warm H2O. This caused slight fumes and appeared to
cause only a mild exotherm. The reaction was expectedly many-fold weaker and far milder than with dilute H2SO4. After agitation especially, a
glittering white precipitate formed. The solution cooled to 25 C eventually on standing, and at that time was filtered. And then washed, the amounts
were approximate with a beaker, around like 20mL H2O for the first wash, then about 10mL for the second wash. Then air dried a few days. Yield: 8.60g
N2H4 sulfate (60.5% of theory). Purity not determined.
Compared to neutralizations with dilute H2SO4 I've done, which are more predictable, don't need purifying washes and give a higher near theoretical
yield (above 90%) even without further isolation from filtrate.
Probable reasons for the bad yield: around 21% of the yield was lost in filtrate and water wash, based on hydrazine sulfate solubility. The filtrate
had that peculiar unique smell of hydrazine. More bisulfate could have been used. The composition of the bisulfate varies (it also can be a
monohydrate). The impure pool bisulfate could use an assay for acid content. I can't comment on NaHSO4 usefulness in synthesis neutralizations. I
would watch out for Na2SO4 crystallizing.
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entropy51
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Quote: Originally posted by Formatik ![](images/xpblue/lastpost.gif) | The composition of the bisulfate varies (it also can be a monohydrate). The impure pool bisulfate could use an assay for acid content.
| I think the pool bisulate is usually the monohydrate.
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Random
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It looks like I will then need to make some H2SO4 to hydrolize ketazine. CuSO4 electrolysis seems easiest for dillute H2SO4.
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NurdRage
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Would you be able to find sulfuric acid based drain cleaner? Even if the acid is horribly impure the hydrazine sulfate can easily be recrystallized
for maximum purity.
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Random
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I looked on many places, but I haven't found it. I was thinking about few other ways of production of it though:
1. Conversion of FeSO4 that is cheaper than CuSO4 to CuSO4 by some way like electrolysis. And then electrolysis of the resulting solution to H2SO4.
2. Dillute nitric acid (it would be mixed with some chlorine but it would only help) made from NO2 (Cu+HCl+Nitrate salt) and then react it with SO2
from metabisulfite + HCl.
3. SO2 + H2O2 --> H2SO4
4. Something like lead chamber process but I don't have enough lead to make it, it read it can be done using dillute concentrations in a PET bottle
too.
5. React Cl2(g) + SO2(g) in water.
Every seems hard, though electrolysis of copper (II) sulphate with graphite anode and copper cathode and then filtering that should yield like 12%
H2SO4 or something like that, which could be then used for Hydrazine.
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UnintentionalChaos
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Here's a video for anyone interested. I used a hybrid of the Hofmann and nurdrage's procedures to avoid exposure to free hydrazine. At no time during
the synthesis was I able to detect any hydrazine smell (though I had carefully smelled a small amount the first time I ran the synthesis so I would
know what it smelled like). The butanone azine has a significantly higher boiling point than free hydrazine so I was less concerned about exposure to
that. The azine does have a strong and (to me) pleasant smell though.
Part 1: http://www.youtube.com/watch?v=JCrDttuw5co
Part 2: http://www.youtube.com/watch?v=URIAB32Q_JQ
[Edited on 2-28-11 by UnintentionalChaos]
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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Random
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You have awesome channel and I see you often post your videos, I think those are really nice so keep up the good work ![:D](./images/smilies/biggrin.gif)
That synthesis with urea looks a lot better than ammonia, because urea is cheaper and more available, also there is not excess water.
Now I have everything what I need for ketazine synthesis, later I could hydrolise that to hydrazine sulphate, do you know if MEK ketazine is very
toxic and dangerous to store? I actually didn't know that hydrazine was so toxic, I am afraid of nitrogen oxides and such things, while I thought
hydrazine wasn't dangerous. It looks I was wrong.
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NurdRage
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Great work!
hydrazine is now completely within reach of everybody. The easy, low equipment requirement, and high yields of the original hoffman process, the high
efficiency and materials savings of the hybrid process, and the highly robust (although expensive/labor intensive) ketazine process.
@random
I'm not certain about long-safety and toxicity of the azine. but the azines themselves are somewhat safer to handle than hydrazine since they are less
volatile and not explosive.
sigma aldrich sells azetone azine directly so you might want to check the MSDS.
[Edited on 28-2-2011 by NurdRage]
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Magpie
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Beautiful presentation! This is great as no fume hood is required. I like the presentation of the Hofman degradation mechanism- very well done!
The single most important condition for a successful synthesis is good mixing - Nicodem
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AndersHoveland
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Unusual procedure hydrazine
Here are three lesser known procedures for preparing hydrazine:
USING OXIME PROTECTION
250mL ammonium hydroxide solution (20-30%)
100mL methylethylketone (MEKP)
0.25 moles sodium hypochlorite
(186g of 10% conc, or 310g of 6% conc solution)
until bubbles stop, about 10 minutes
oily layer will gradually form on surface, use separatory funnel to remove top layer
separately prepare a solution of:
100mL water
10mL 20%conc sulfuric acid
then pour in the oily layer from first preparation. The
solution becomes cloudy. filter out hydrazine sulfate
The following optional adjustments will improve yields: add the bleach very slowly using an addition funnel, cool the reaction with ice bath, boil the
MEKP off before separating out the hydrazine sulfate. Up to 60% yield (based on initial hypochlorite) could be obtained, this is considered extremely
good
USING UREA INSTEAD OF AMMONIA
There should be between 0.8 to 1 mole of hypochlorite for each mole of urea. For the one mole ratio of NaOCl, the yields were 50% with respect to
urea, and 50% with respect to NaOCl. For the 0.8 mole ratio, the yields were 48.5% with respect to urea, and 60% with respect to NaOCl. For best
yields, the hypochlorite solution should contain at least 3g of sodium hydroxide for every 0.8 moles of sodium hypochlorite. Solutions of sodium
hypochlorite and urea were first both cooled to 4degC, then mixed. A glue solution was added, 0.5g of glue for each mole of sodium hypochlorite. The
mixture was heated to 90degC, then allowed to cool. This exact temperature is very important for good yields from the reaction. Sulfuric acid was
added into the solution so that the concentration of acid in the solution reached 20%. Hydrazine sulfate precipitated and was filtered out, then
washed with alcohol and dried at 100degC. Note that the reaction cannot be done in a steel pot, as this catalyzes the decomposition of hydrazine.
OXIDATION WITH PEROXIDE
Hydrogen peroxide can be used to oxidize ammonia, with methylethyl ketone being used to protect the hydrazine as it forms. Acetamide, with some
Na2PO4H added, must be present to activate the hydrogen peroxide, because otherwise the hydrogen peroxide and ammonia will not react. E. G. E.
Hawkins, J. Chem. Soc. C, 2663 (1969). First, under the fairly alkaline conditions, ammonia condenses with the ketone to form an imine. The acetamide
forms intermediate iminoperacetic acid, which then oxidizes the temporary imine to form an intermediate oxaziridine (which has a triangular ring with
a C, N, and O atom. This ring immediately oxidizes an NH3 to form a hydrazone, which then condenses with another methylethylketone, protecting the
hydrazine from further oxidation. The layer of methylethyl hydrazone separates out as a separate upper layer, which is decanted off.
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NurdRage
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Ya know... your first method would have been cooler if you didn't blatantly RIP-OFF my video, i even specified the exact same quantities....
Although the amount of sulfuric acid you specify is wrong and wouldn't yield very much hydrazine sulfate.
[Edited on 3-3-2011 by NurdRage]
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bbartlog
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So, where did you get the first procedure? When I see MEKP and sodium hypochlorite mixed, I tend to assume a haloform reaction will take place. Does
the excess of ammonia mitigate this somehow? Or does the hydrazine reaction just take place faster? In short, are we supposed to believe that those
who go to the trouble of doing this in two steps (make hydrazine, *then* add MEK) are just making life difficult for themselves?
(edit): actually I see that you've just copied NurdRage's method from upthread (and from his video as he notes). Interesting. Sounds like the
hydrazine reaction outruns the haloform reaction.
[Edited on 3-3-2011 by bbartlog]
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UnintentionalChaos
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This is AndersHoveland...
I believe he was banned last time for spewing inane procedures that he had pulled out of his ass (often that made no sense) all over the forum. It
looks like he's on his way to a repeat of that fate.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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NurdRage
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Yeah....
His second method is so vague as to be useless. If he means to replace the ammonia with urea from the ketazine process then i suspect its a blatant
fabrication.... because i actually TRIED very hard to make a urea-ketazine process where i add the MEK and the urea together first... lets say i got
all sorts of fun organic products except hydrazine.
i guess though he ripped another procedure, not a MEK based one. Those numbers sound familiar, i just can't put my finger on where.
[Edited on 3-3-2011 by NurdRage]
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madscientist
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Quote: | I believe he was banned last time for spewing inane procedures that he had pulled out of his ass (often that made no sense) all over the forum. It
looks like he's on his way to a repeat of that fate. |
Yep.
AndersHoveland - how many times do we need to tell you to use references? You've already long established yourself as unreliable. Everything
you post needs to be verified.
I weep at the sight of flaming acetic anhydride.
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Rosco Bodine
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It seems it's going to be a long wait for me to see any truly significant improvement posted which goes beyond the improved method of
Mr. Anonymous .....
http://www.youtube.com/watch?v=uPHmsEoLsL0&fmt=18
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NurdRage
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The hybrid process was just posted by unintentionalchaos, it greatly reduces acid wastage and is partially recyclable. I think that's a significant
improvement.
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Rosco Bodine
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Acid wastage? Yeah okay if you say so. I see a lot of time wastage from added complication, a lot of unnecessary glass plumbing, gradual additions
which are yield crippling for what is an inherently "mass reaction" optimized situation
where reactants for the rearrangement need to be added in a lump to react en masse. The yield is likely being reduced by several variations on the
process. The yield probably suffers specifically from scaling downward because of an unfavorable thermal dynamic, because it is very likely the
reaction benefits from a sort of "critical mass" for the reaction quantity which enables it being self-driven by its own exotherm. If the scale and
method I described was followed quite precisely in all details, there should be no reproducibility issues for independent confirmation and
verification. The variations on a process susceptible to variables is what is introducing variables which are causing the yield problems. Following
precisely the procedure I described, not on a different scale or with any variations or modifications whatsoever, should eliminate yield
reproducibility issues. I still absolutely unequivocally stand behind what I reported in the improved procedure
http://sciencemadness.org/talk/viewthread.php?tid=757#pid653...
with regards to all of the described details of the process
and the reported yields. For the dubious, I would say
carbon copy, explicitly duplicate the process I described and the results should be consistent with what I reported.
If you do anything differently scalewise or otherwise and
then don't get as good yield, then logically it is probable that what was different is the reason for diminished yields for whatever technical
explanation there may be. Analysis of the variables is an entire project by itself. However for the
scale and for the process I described, that information is reliable. The half gallon of pool chlorinator batch size would probably work fine in a 6
liter Erlenmeyer or a 6 liter Florence
which should contain all the foam without need for an overflow funnel. A full gallon of pool chlorinator batch size
could probably be done in a 12,000ml flask without overflow, but I can't guarantee what would be the foam dynamic there because I haven't tried it. A
full gallon batch size should go fine in a 22liter or three gallons in a 50liter reactor. Have a ball with it if you have some process competence.
But a closed garage without specific process ventilation is probably not a proper environment for this kind of experiment.
[Edited on 6-3-2011 by Rosco Bodine]
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NurdRage
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I'm not sure i see what you're specifically arguing.
Are you implying his method does NOT reduce acid wastage?
It looks to me you're arguing something else other than what i am claiming (reduction in acid usage)... i'm not sure what exactly.
If you can tell me in one line exactly what it is, i can give a more appropriate response.
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Nicodem
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Quote: Originally posted by AndersHoveland ![](images/xpblue/lastpost.gif) | OXIDATION WITH PEROXIDE
Hydrogen peroxide can be used to oxidize ammonia, with methylethyl ketone being used to protect the hydrazine as it forms. Acetamide, with some
Na2PO4H added, must be present to activate the hydrogen peroxide, because otherwise the hydrogen peroxide and ammonia will not react. E. G. E.
Hawkins, J. Chem. Soc. C, 2663 (1969). First, under the fairly alkaline conditions, ammonia condenses with the ketone to form an imine. The acetamide
forms intermediate iminoperacetic acid, which then oxidizes the temporary imine to form an intermediate oxaziridine (which has a triangular ring with
a C, N, and O atom. This ring immediately oxidizes an NH3 to form a hydrazone, which then condenses with another methylethylketone, protecting the
hydrazine from further oxidation. The layer of methylethyl hydrazone separates out as a separate upper layer, which is decanted off.
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I was so shocked that you actually included a reference in that delirious post that I actually verified it (DOI: 10.1039/J39690002663). As expected, it has nothing to do with hydrazine synthesis and oxaziridines are not claimed as intermediates. That
paper is about oxidation products of cyclohexanone/ammonia with H2O2 and no hydrazines, hydrazones or hydrazides are mentioned among the products (the
products are mainly those derived from some sort of a Bayer-Villiger-like reaction on the cyclohexanone derived imine).
I can guess though that aimed at perverting the otherwise known oxaziridine based syntheses of hydrazones: Synthesis, 1991, 327-341, DOI: 10.1055/s-1991-26459 (attached).
I would appreciate if you would limit yourself to only post truth and nothing else but the truth - WITH TRUE REFERENCES!
Attachment: Electrophilic Aminations with Oxaziridines.pdf (1MB) This file has been downloaded 3008 times
[Edited on 6/3/2011 by Nicodem]
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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Rosco Bodine
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Ever heard that old phrase "penny wise but pound foolish" ? Maybe there is something of a mystery solving nature there in that cogent old phrase
about economy, useful for decryption of my mysterious comments.
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UnintentionalChaos
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Quote: Originally posted by Rosco Bodine ![](images/xpblue/lastpost.gif) | Ever heard that old phrase "penny wise but pound foolish" ? Maybe there is something of a mystery solving nature there in that cogent old phrase
about economy, useful for decryption of my mysterious comments. |
You have noticed that this is an amateur science forum, not a manufacturing plant, right? Most members here might have use for at most, a few mol of
hydrazine sulfate, and almost surely not all at the same time. Since this is a hobby, they are not paid for their time and generally time spent doing
chemistry is enjoyable to them.
I do not own any glassware larger than a liter, nor do I often have any use for such. For those doing such smaller scale organic chemistry, the
glassware I used is most likely at the ready. 3 and 4L flasks and beakers are not. I went out of my way to use highly pure chemicals for this prep to
avoid any chance of metal ion contamination in the product. It takes an obnoxious amount of time for me to distill azeotropic HCl and remove the iron
contamination or whatever it is that gives it that lovely yellow color and I am not keen on throwing away several mole equivalents for direct
neutralization.
Additionally, the smell of the azine is rather nice. While not healthy, I'm sure, it's worth a whiff.
I think you're just bitchy that nobody has given your ego a handjob lately over the original prep, but that's just my interpretation of the whole
thing.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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Rosco Bodine
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If everything you were doing was right on track then where's the beef, where is the yield improvement or the process enhancement or simplification? It
isn't there, so what exactly is the improvement? I haven't asked or been paid for my time sharing some insight into processes that I do understand
with others, some of whom take offense at the theory or implication they don't know it all already .....
but who obviously know enough to correct or criticize or me, and if I'm actually wrong then I can appreciate the information. I don't need my ego
stroked. I would settle for the respect of a presumption on the part of others that I do have two brain cells to rub together and make a spark.
Chemistry has dynamics about reactions which are real. You can accept that or pretend it isn't so and that variables don't matter. I have read posts
that question the veracity of what I have reported because of variations by others on a process that was accurately described one way, being done a
different way by others then seeing inferior results ....
Well Duh ....go figure why. Sure there is more than one way to skin a cat. That doesn't make plan B,C,D ect. necessarily
an improvement just because they are different from plan A.
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NurdRage
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I still don't know what he (rosco bodine) is so pissed off about. Can someone else tell me what's offended him so much? I wanna fix it, but i don't
even know what the issue is.
@UnintentionalChaos have any plans to try the ammonia based ketazine process? Even on a small scale. I'd like to see how reproducible it is for
others.
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Rosco Bodine
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I am not pissed. HCl is a cheap reagent so the acid wastage stuff is bs.
Using a ketazine variant (benzaldazine) isolation method was posted early in the thread, a German patent to a Russian named Shestakov. So this is not
real news
except for the use of MEK being possible.
The interesting thing about a ketazine isolation method for hydrazine is a different matter.
What would be interesting is to see what may occur upon nitrosation of the ketazine in methanolic sodium hydroxide with isopropyl nitrite, or by
nitrous gas nitrosation perhaps in the presence of isopropyl alcohol forming the IPN in situ.
Glycerin, ethylene glycol, or butanol in small amount may work better than isopropyl alcohol due to the less volatile nitrite which would function as
a regenerable nitrite reagent in the system. Perhaps this could shortcut the route to sodium azide. Now that would be an improvement for a process
whose eventual target product is sodium azide.
The nitrous gas I am contemplating would be by the method of Griess and Microtek using starch to decompose warm moderately concentrated HNO3. I think
I recall from somewhere that paraformaldehyde can be used in the same way as starch for decomposition of HNO3.
Go back and check page 5 halfway down the page
http://www.sciencemadness.org/talk/viewthread.php?tid=1128&a...
The patent is here
DE164755 Schestakow , Hydrazine by Urea Hypochlorite.pdf (157kB)
http://www.sciencemadness.org/talk/files.php?pid=43024&a...
Also some commentary by Nicodem
http://www.sciencemadness.org/talk/viewthread.php?tid=1128&a...
[Edited on 7-3-2011 by Rosco Bodine]
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