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maxidastier
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Those who may be familiar with nitroguanidine have realized that a very useful energetic has been hampered by the very difficult, large and flexible
needles resultant in a very simple synthesis. The alteration of this to a highly dense and pourable material could have substantial applications (if
they are not already used in triple based smokeless powders). |
Well, I like those needles. They look beautiful.
But Nitroguanidine is is really used in triple based smokeless powders.
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prometheus1970
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ETN in straight acid and proper neutralization
I've finally gotten fed up with wrestling with KNO3/H2SO4 for making erythritol tetranitrate(ETN). I've noticed that by the time my nitrating bath
has cooled to 10C, most of the KNO3 has precipitated out of solution thickening it to where it's all but impossible to stir, especially when I have to
add more powder (erythritol[E]) to the mix. I bit the bullet and ordered some HNO3 (and NAOH for neutralizing). I found a synth for etn using
straight acids instead of H2so4/ nitrate salt. Here's basically how it goes:mix 2 vols h2so4 to 1 vol hno3 10 ml nitrating mix per gram of erythritol
+ 40% excess nitrating mix beyond that add E in portions keep >20C. After last addition leave 30-45 minutes add 25% total volume ice cold h2so4,
react 5 min. dump into 10 times total volume ice water/bicarb, filter , etc. I'm wondering if this is a valid synthesis or a bunch of crap. Also
will it be okay to neutralize with naoh instead of bicarb as long as I use small amounts (weak solution) and am careful not to overdo it (leave it
basic)?
Just because you're paranoid doesn't mean everybody isn't out to get you.
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quicksilver
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One of the reason that kitchen chemistry often times doesn't get the results that a synthesis projects is the equipment just isn't available. A heavy
stir-bar will continue to rotate even in some nearly "porridge"-like nitrations. There are also designs (oval) that appear to "cut through" very heavy
fluids.
There is no question what so ever that nitrated polyols have stayed in great shape over years because they are truly neutral (7) I would advise
against moving any nitration over from neutral. - But especially ETN. There are enough common stabilizers so that one need never consider pushing
into areas unknown.
There is really just not enough quality research on that material. Moving nitrated benzene ring explosives to basic ( like TNT!) puts them in a very
sensitive condition that is unacceptable industrially.
An experiment in the milligram range might be acceptable IF it was really deeply sub-gram weight. Not enough is known about ETN other than it is VERY
sensitive (somewhat akin to MHN) and that is NOT something to take lightly.
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Rosco Bodine
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Threads Merged 13-12-2010 at 19:57 |
DougTheMapper
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Just out of curiosity, what does a stabilizer actually do? Not in the sense that it slows decomposition, but what is the reaction mechanism? Does it
act as a buffer to absorb minute traces of compounds which slowly destroy the material, or does it isolate the material from itself so that "defect"
molecules don't generate things that destroy adjacent ones, or what?
I know 0.5 or 1% urea is often used as a stabilizer for ETN and the like but I really don't see how it helps.
Victor Grignard is a methylated spirit.
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quicksilver
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Well, there are several common methods and in course; answers to that query. Most commonly many stabilizers prevent or slow decomposition by
addressing the mechanism of that decomposition - therefore they act in differing ways. They may absorb released nitrogen while some maintain ph
equilibrium (more pointedly).
One fascinating stabilizer used in smokeless powders and common nitric ester explosives is DIPHENYLAMINE. One of the most interesting characteristics
of this stabilizer is that when used with a white or clear crystalline explosive, it will yield a BLUE color when the materiel degrades (& yields
nitrous acid). In this instance the stabilizer is (in a sense) absorbing the nitrogen. While another common stabilizer ETHYL CENTRALITE does somewhat
the same by a differing method: a deterrent coating
It is EXTREMELY important to rid nitrated products of acid. Solid explosives are very difficult to rid excess acid and that is WHY re-crystallization
is SO IMPORTANT. In fact, if re-crystallization is not a part of the synthesis, it is almost a guarantee that the nitrated material will eventually
decompose. While other highly nitrated products, properly re-crystallized can maintain their stability for years! A decomposing explosive eventually
becomes so unstable it may explode for very little stimulation. The "time table" of decomposition is dependent upon the base material, the type or
procedure of nitration and the existing anti-acids in existence or proximity to the explosive. But proximity will do no good after a time. The INSIDE
of the crystal lattice must be neutral.
This is a very basic (no pun intended) aspect of explosive synthesis via nitration. Without understanding chemical stability the synthesis of
explosive material is insane!
Not all stability rests on a foundation of acidic neutralization. In some cases (azides) crystal shape plays an extremely important role. Other
explosives have limited temperature ranges that they can be exposed to (fulminates) and after which decomposition proceeds.
edit:
There is a lot more to this: some years back Roscoe turned me on to a stabilized known as Betain which is a B Vitamin! (I don't know if he wants to
weigh in on this subject) but this is VERY important, actually VITAL if the study of energetic materials ever leads you to synthesis. This may be
(IMO) perhaps the truly significant element of lab which cannot be overlooked!
(See: NAOÚM, DAVIS, etc - for more specific information)
[Edited on 14-12-2010 by quicksilver]
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DougTheMapper
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I propose an experiment:
Prepare several small samples of ETN, one un-neutralized, one neutralized but un-recrystallized, and the rest neutralized, recrystallized, and
stabilized with the various compounds listed above. A drop of water is added to each dry sample and they are then stored at an elevated temperature
(not over the melting point, so not exceeding 60C) in the presence of a pH test strip.
The samples which undergo decomposition will undoubtedly lose their nitrate groups first, forming weak HNO3 in the water vapor present which will be
indicated by the pH paper. If done in clear vials with a time-lapse camera, the "best" stabilizer will likely be made apparent by the color of the pH
paper.
A bit off-topic - perhaps we should start a thread on stabilizers.
[Edited on 14-12-2010 by DougTheMapper]
Victor Grignard is a methylated spirit.
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Rosco Bodine
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This may help
http://www.sciencemadness.org/talk/viewthread.php?tid=12623&...
Please don't start a new thread on stabilizers, spare me the task of merging threads ......okay?
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DougTheMapper
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Ah, thank you Rosco. I actually did do a google search of the board but missed the thread by a search term.
Also, a thought about the discussion earlier in this thread about recovering spent acids: Perhaps the careful addition of hydrogen peroxide followed
by gentle and then strong heating could safely dispose of any nitrated organics in the acid mix, followed by the distillation of the excess nitric
acid and then concentration of sulfuric while oxidizing and destroying organics. Once the explosive properties of the synthesized compound are
neutralized, it simply becomes a matter of destroying organics and re-concentrating; this is something that's routinely done with contaminated
hardware store sulfuric anyway.
As a second thought, perhaps a solvent extraction of the energetic material from the mixed acids could work to separate the two, followed by the
processing of the acids and recrystallization of the product from the solvent. It would have to be a pretty robust solvent though...
Otherwise, I can see how filtering insoluble product from the relatively concentrated mixed acids could pose a challenge to all but glass filters,
ditto liquid or soluble product...
[Edited on 15-12-2010 by DougTheMapper]
Second edit: Imagine a nitrated liquid energetic that a solid nitrated energetic is soluble in. A solvent extraction might work with something like
methyl nitrate as the solvent since it wouldn't be affected by the mixed acids and could theoretically dissolve a previously nitrated solid suspended
in the acids. It should end up a liquid phase nearly insoluble in the acids so it can be run through a separatory funnel. Presto, there's the acids
ready for reconditioning. This would, of course, depend on the solubility of solid energetics in various liquid energetics, something not well
documented by any source I've seen. I sense a whole lot of experimentation in my future... now to find a liquid organic nitrate that ETN is soluble
in...
[Edited on 15-12-2010 by DougTheMapper]
Third edit: I forgot to mention that I have no idea what I'm doing, so please be careful if you are going to try this. In my head it works perfectly;
in reality it could end in some cataclysmic explosion.
[Edited on 15-12-2010 by DougTheMapper]
Victor Grignard is a methylated spirit.
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maxidastier
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These are some really interesting thoughts you've made, because I'm always trying to be as economic as possible when making exlosives which means acid
recovery is one of the most important, but also most difficult and dangerous t aspect.
Quote: |
Otherwise, I can see how filtering insoluble product from the relatively concentrated mixed acids could pose a challenge to all but glass filters,
ditto liquid or soluble product... |
That is really a problem. Because if you don't have a glass filter funell you are forced to dilute your acid mix to 10 times of the volume with water
which makes acid recovery useless.
Therefore a glass filter is really a useful thing. On the one hand you can use vacuum filtration, and on the other, you've to add only the smallest
amount of water needed to precipitate the ETN from the acid mix, and can therefore recover spent acids easily.
Another idea in respect of ETN is its low melting point (60°C).
I've read about preparation method that was carried out at 25°C and later heated to about 55°C, so that the ETN finally formed a molten layer at the
bottom and could be seperated from the acids without diluting (so easy spent acid recovery is possible)
Maybe someone has more detailed information on this or a working method?!
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Rosco Bodine
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Try the Darwin Awards committee, maybe they can help on that melt purification.
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maxidastier
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What's your problem exactly? The heat / danger of explosion?
I wouldn't have posted it if the patent on this preparation method didn't exist. In fact there are several explosives that can be prepared at higher
temperatures.
I'm not finding the right pdf now, but just to prove the "heating" method exists, although it's not said you can also separate the ETN molten layer.
Here is a similar screen of a pdf:
Feel free to state your opinion but not like in your last post, please-
[Edited on 14-2-2011 by maxidastier]
[Edited on 14-2-2011 by maxidastier]
Attachment: ETN.doc (684kB) This file has been downloaded 695 times
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quicksilver
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Well many people who have distilled acid for an experiment have thought of retention of that work for simplicity in the next but obviously once a high
concentration acid has been used, it changes. Additionally there are practical considerations with acid recovery.
The rewards are not worth the risk in acid recover designs; that's why it's been dropped in any modern facility. One thinks of liquid such as glycol
being a problem but actually methodology to eliminate an energetic solid will not guarantee purity [in the acid] enough to risk a chain detonation.
Obviously this is more true in organic ester models than benzene ring materials that's why you may have read some OLD recovery agenda with TNT or
what-have-you. However those concepts were actually worked on during war time and not continued (for the above reasons).
There were some ideas that could be worked in a plant-level setting; however they are complex as they use techniques that require much more than
glassware & temp applications.
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Rosco Bodine
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Quote: Originally posted by maxidastier | What's your problem exactly? The heat / danger of explosion?
I wouldn't have posted it if the patent on this preparation method didn't exist. |
Then support what you say by posting the patent.
Yes thermal decomposition of acid laden ETN is likely at a lower temperature particularly in a spent nitration mixture.
Quote: |
In fact there are several explosives that can be prepared at higher temperatures. |
In fact ETN and nitroglycerin are probably not two examples because they are temperature sensitive particularly in the presence of acid impurities.
The technique of melt separation is more usual for a nitroaromatic not a nitroester.
Elevated temperature nitration schemes may be possible, though not necessarily safer or better for a more stable
nitroester like PETN. But this sort of nonsense is really stupid and unnecessary risk with ETN.
Quote: |
I'm not finding the right pdf now, but just to prove the "heating" method exists, although it's not said you can also separate the ETN molten layer.
|
According to whom ....a fraudulent dangerous moron like Jared Ledgard,
because this process sounds just like some totally stupidass hare brained shit straight from one of Ledgards explosives chemist wannabe synthesis wet
dreams.
Quote: |
Here is a similar screen of a pdf:
Feel free to state your opinion but not like in your last post, please-
[Edited on 14-2-2011 by maxidastier]
[Edited on 14-2-2011 by maxidastier] |
Okay try it this way
http://www.sciencemadness.org/talk/viewthread.php?tid=14437
The elevated temperature nitration process for PETN is described in the attached patent GB364624 but this process is for PETN which is probably the
most stable nitroester while ETN is one of the least stable and would not lend itself to the same provocation by extreme conditions.
Also here is a link to the thread which possibly started the publicized "amateur" interest in ETN as near as I can tell.
http://www.sciencemadness.org/talk/viewthread.php?tid=890#pi...
And in the years since, it seems everybody but Jared Ledgard has become an expert. Do not trust as science or even as good guessing
what Ledgard writes. It is a collection of edited/plagiarized and unchecked articles mingled with false representations and errors and bullshit
theory of Jared (wish I knew chemistry as good as I think I do) Ledgard ....pretender of knowledge. Ledgard can't even plagiarize accurately. Look
for example at Ledgard specifying 98% H2SO4 just because Ledgard thinks that it doesn't matter to not use 90%-95% like the patent says.
Well hey, reality check ...it matters. And what is that the third edition ....maybe on the fourth or fifth edition Ledgard can transcribe and
plagiarize accurately.......ya think.
Attachment: GB364624 Rapid Nitration of Sulfonated Pentaerythritol.pdf (204kB) This file has been downloaded 843 times
What quicksilver is saying holds true. On a plant scale process the economics especially in wartime production causes risks to be taken with acid
reprocessing and on the edge economics versus safety to be justifiable. And it is correct to run a nitration on the warm side to avoid accumulation
of unnitrated product which can surge and go into an exotherm avalanche. But with nitroesters you risk decomposition of the already nitrated product
at the warm side of the window nitration temperature where the spent acid becomes more of an oxidizing mixture than a nitration mixture, and the more
sensitive the particular nitroester, the more dangerous is the pushing of a nitration. In my opinion hot batch nitrations of most nitroesters
is a scenario where it is only a matter of time before she blows. You can literally watch the nascent red fumes appearing on the transition, even
with PETN and in a batch process nitration where the product isn't being continually drawn off .....your nitration is potentially a ticking bomb with
the ticks getting closer together with each degree rise in temperature .....and on the avalanche the whole thing can cook off in seconds even before
you have time to drown it.
So take your chances if you want ....it will only go wrong once and then all your problems will be over. He was economical with his acids is not
much of an epitaph.
On a plant scale they can have sensors and analysis of the nitrous levels from decomposition and have a margin of operational safety because they know
where the limits are in the process continually monitored. You don't have that monitoring in a beaker. All you got is your eyes and a thermometer
and a pair of tumbling dice on the process.
[Edited on 15-2-2011 by Rosco Bodine]
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maxidastier
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Well, good that I didn't try out that heating method yet. Thanks for saving my life
Just didn't know that this Ledgard is such a badass
So that's not the right way. I surely know that acid recovery is too dangerous. But still there has to be a way for the hobby chemist, at least for
some HEs.
If I've got my ETN ready nitrated and then filter it off through a glass filter funnel, could I distill the acids afterwards? What would be the
danger? Is there too much ETN left or are the side products of explosive character as well?
[Edited on 15-2-2011 by maxidastier]
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Rosco Bodine
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Ledgard just plain does sloppy work in a technical field where precision is needed.
The devil is in the details. Ledgard doesn't sweat the details that exist, taking
descriptions out of context and oversimplifying and omitting important information, not providing accurate references, and supplying information also
that is just plain false. So the title of his work is misleading to people who would read it like a cookbook and start cooking, not aware of the
significant omissions and errors.
Recycling acids is generally tedious and dangerous. There are technically possible ways of managing acid recovery, but there are specific treatments
for the spent acids which have to be done first to destroy or extract dissolved residues of product and byproducts. Nitration plants have worked out
schemes for doing this cleanup of the spent acids, knowing in advance what the expected residue contaminants are. Generally you can't safely just
redistill the acids because at some point in that distillation there will be an explosion of the accumulating byproduct residues and/or the recovered
acid will be so contaminated that it is useless for future use in nitration. I haven't really looked into or experimented with recycling acids, or
surveyed which nitrations may provide a relatively safe spent acid recycling opportunity. The processes for dealing with spent acids from
nitroglycerin nitrations may be adaptable to spent acids from ETN nitrations. What is technically possible to do in order to recycle the acid for
nitration may not be as economical as diverting the spent acid to being salvaged as a byproduct like fertilizer where the acids are safely sequestered
as benign compounds that can be purified easily if needed.
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Contrabasso
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Ledgard cites patents, not always accurately, and patents are known for NOT giving all the details, or the precise conditions of a reaction. While
there may well be good ideas in there, there are certainly no recipes for a cook to follow. The chemistry may be interesting BUT only if you know what
you are reading and can work out the real method with ALL the necessary precautions.
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Rosco Bodine
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Ledgard is too slack to even cite the number of the patent to facilitate access, but instead he gives an application number and then leaves another
search
for the reader ....if indeed he even sites the damn application number right
or even describes the content accurately without adding his own "interpretation".
There simply is no excuse for that slackers pathetic standards.
As for patents reliability, true some of them are abysmal, but those are the minority particularly with regards to chemical patents issued to parallel
what are also academic journal articles. There really is such a thing as "skilled in the art"
where there comes to bear understanding of the patent technology sufficient
to read between the lines and beyond them. Particularly with regards to processes that are illustrated only by one general example .....the optimized
process may be deliberately not described. There is such a thing as being able to observe and read a reaction and make adjustments accordingly while
the process is being performed, because many syntheses are subject to variability which requires making compensation adjustments on the fly. But
somebody who is not understanding what is happening won't be able to do that reaction management.
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quicksilver
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The fact that you can not count the mistakes of Legard's texts on all your fingers and toes is a very good reason to avoid loosing some of them.
ETN is not a material with a lengthy history of research. It originally was entirely too expensive to be used commercially and was generally
considered more of a lab curiosity than a viable candidate for commercial production. Even MHN was more economical & therefore the level of
research was very modest. To get some idea of it's (ETN) rarity in research since the often quoted Nov.20th patent look to how much room was devoted
to it in most every common source from Weaver, Naoum, Davis, Munroe, Urbansksi, Federoff, Shiffield, Akhavan, Cook, Conkling, etc. If you exclude
patents and issues regarding patents, less than 5 single spaced pages are commonly available.
edit:
I actually was pulling books & searching PDF's to check this & I really can't find more than 5 pages of material from a fair collection of
texts. There is MUCH more available on CL20 than ETN.
[Edited on 15-2-2011 by quicksilver]
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Rosco Bodine
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The absence of extensive information concerning ETN is exactly why when I first posted about it I said it should be considered experimental, and years
later it remains something of a lab curiosity having unexplored potential.
It doesn't have the stability or safety of PETN or some other nitroesters that are more practical.
I think the real novelty of ETN is it can be easily made from OTC materials, and it is an easily detonable solid high energy brisant nitroester having
reasonably good but not great storage stability. It is a good expedient explosive having a sort of niche application interest, a good energetic
material to know about for possible use where it may be good enough for the task at hand. Nobody should want to have any substantial quantity of it
sitting in storage for a very long time particularly in a warm location. It eventually will deteriorate, however for the stabilized material it may
take many years before slight discoloration or decomposition becomes evident. My first sample took seven years in ordinary outdoor storage before
slightly discoloring, so for the urea stabilized ETN a five year shelf life is probably a reliable figure. I have a suspicion dicyandiamide or
betaine
may fare better as a stabilizer than urea.
[Edited on 15-2-2011 by Rosco Bodine]
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maxidastier
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Well, thanks @all for your input. As it may have sounded I don't take acid recovery from ETN as my prior task
But there are other HEs which we know rather good and that's what I'm onto ( PETN, RDX etc.) There should be enough information on them to work out a
recovery set up for the hobby chemist. Why is no one really interested in working it out? (Some) People here are interested in things that are half
as much useful but twice dangerous. I'm just wondering why this topic is not popular while there is a bunch of threads on topics like "How to distill
nitric acid/ Where can I get my acid" but this could be avoided if we worked out a acid revovery method for at least common HEs like PETN, RDX.
Well, but you mentioned making fertilizer from it? Are there other more useful things?
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Rosco Bodine
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The lack of interest in acid recovery is because it is tedious and energy intensive to the point that the economics are unfavorable aside from the
dangers involved.
Hydrogen peroxide would be the likely oxidant used to treat spent acid for the digestion and burning out of organic impurities prior to a
reconcentration and fractionation. So you have the expense of the H2O2 and the time and energy and equipment costs, and the return in recovered acids
doesn't make it worthwhile in most processes. Neutralizing spent acids with ammonia or urea or lime might be worthwhile but then you need the
accumulation tanks, separators, and evaporation / crystallization pans for that. Industrially acids are cheaper
to make clean and neat in the first place, than is it practical to recover the acids
from their spent byproducts. The same unfavorable economics will apply to laboratory use. For nitrations where no sulfuric acid is used the
situation is better since the spent acid is primarily HNO3 with some water content along with organic byproducts. Also there are multi-stage
nitrations where the spent acid from the higher stage nitrations is recycled and used for the lower stage nitrations
of fresh material being nitrated. TNT and RDX manufacture are adapted to such
a method because the chemistry involved is favorable. However that is not the case for all energetic materials. For many products it simply isn't
practical or economical to recycle the spent acids. Most chemists can look at a process and
recognize what sort of recovery of useful byproducts is possible and then devise
methods for accumulation of the things wanted to be kept. Likewise. chemists are able to recognize what are spent waste products that are for
practical purposes worthless for not being worth the cost or effort to further process.
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maxidastier
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Ok, so if you had got the acid mix from making ETN, what would you do most likely apart from draining it?
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Rosco Bodine
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If you just want to sequester the otherwise wasted nitrogen, perhaps something easily nitrated to the mononitration stage maybe naphthalene or toluene
for example could be digested with the waste acid and that would strip a fair amount of the otherwise lost nitrogen from the mixture. This is just my
guess of a possibility as I have never really seen this described, although it would seem possible to do. Neutralizing the remainder with lime would
precipitate as gypsum the sulfate and the supernatant liquid would be mostly calcium nitrate.
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quicksilver
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I was thinking the same thing. It's not mandated that you destroy it but there are a limited number of items that could be used as idea from the
above, perhaps cellulose or starch, etc......But in general the trade off is heavy with risk even from the standpoint of lack of purity or weakened
available strength.
What MIGHT be interesting is to allow a droplet to evaporate to it's fullest degree and examine it microscopically. Even glycol and related liquids
once nitrated eventually crystallize. Certainly it's within possibility that a solid would leave behind some trace crystals. If you had access to a
full lab most any chromatography machine would be very revealing. Since the source of much H2SO4 is waste, there would be a complication that would
have to be accounted for.
It's simply that as a generality, lab-level concepts of recycling acid from a nitration is not a good idea. However stepping outside that arena may
have some utility.
[Edited on 17-2-2011 by quicksilver]
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Rosco Bodine
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Naphthalene would be a likely choice of material for nitration using spent acid from more concentrated nitrations since the ease of nitration is good,
and the toxicity of the nitrated naphthalenes is low and the stability is good. ( I think ) naphthalene also has the ability to be nitrated by the
nitrogen oxides produced by decomposition of organic residues as would occur in a moderately elevated temperature digestion perhaps gradually ramped
to (possibly)~85C. Naphthalene melts at 80.26C but a lower mp eutectic 36.7C forms between the mononitronaphthalene forming 73.5% and the unnitrated
naphthalene 26.5% .....So I would say naphthalene is the prime candidate
as a nitrogen salvage reagent for a spent nitration mixture. The "double spent" reaction mixture after the nitration and separation of the
nitronaphthalene may possibly be clean enough for a sulfuric acid recovery by concentration and distillation. This is all my theory at this point and
I have never actually tried this, but it could work. Urbanski 1 has a pretty extensive writeup on nitration of naphthalene.
[Edited on 18-2-2011 by Rosco Bodine]
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