Sciencemadness Discussion Board - How well erythritol nitrates in HNO3/H2SO4?

How well erythritol nitrates in HNO3/H2SO4?

Justin - 20-6-2010 at 22:19

Hi, so far i have only used KNO3/H2SO4 to nitrate erythritol, with good yields as has most people, but as odd as it seems i can aquire 70%HNO3 for cheaper and easier than alkali nitrates and i have plenty of it. I've heard that addition of erythritol to HNO3 then add H2SO4 too precipitate the product. Anyone have much experience using HNO3 too nitrate erythritol?

Also after synthesis of NG or EDGN i want too recover my spent acids after separation of product in a sep funnel, what's the risk of explosion of residual NG/EGDN in the spent acids during distillation of residual HNO3? Temp would be raised slowly to 80C, then after all HNO3 distillate comes over heat would be raised to 300C to re-concentrate the H2SO4, i would imagine any residual product would decompose upon slow heating however i would like some input on the dangers of this. It doesnt sound very safe but it would be nice to recover some of the acids. Thanks everyone.

quicksilver - 21-6-2010 at 12:41

Justin, the acid recovery process is just about where most plant tragedies happen. Even with some seriously well thought out scenarios and equipment it's a very, very dangerous situation. Utilizing equipment DESIGNED to minimized friction, pressure, heat, and material build up, the situation is NOT EVER worth the risk.
Many, many years ago (especially during major wars) the idea of a self contained energetic materials plant was never without dire risk. The idea was dropped (acid recovery) during peace-time due to weighing the risk vs pay-off. Most often the concept was to neutralize the energetic prior to recovery but this made the time (man hours) not worth the endeavor. To NOT neutralize the energetic prior to recovery is madness.
Weighing cost vs the POTENTIAL for a tragedy; it's NEVER worth the risk for a home chemist. If you were interested in HOW it was attempted during WWII a great deal can be gleaned from TNT plant production. Investment level was in the tens of millions in 1930's dollars. Today, it would be over the top. Mostly plants that mfg nitrate fertilizer also mfg explosives but in a separate building.

It would be a neat idea but it's really not worth the risk nor the money invested in specialized equipment. Federoff and Weaver have a bit to say on how some of it was attempted. But for the average hobbyist, the probability of catastrophe is high enough to make it an unsound endeavor The specialize equipment alone would be very difficult to find. Many of them would include Teflon to Teflon petcocks not glass to Teflon devices, so right there you have a tough time finding the right items.

It's almost like a "Fortune-cookie" statement: "It's better to ask & find something unsuitable than to attempt and find misery."

Justin - 21-6-2010 at 15:41

Thanks for your input, i agree it's not worth the danger to recover a bit of spent acids.

pjig - 21-6-2010 at 18:26

I have seen in a few cases that the spent acids can be used on a second or third batch of nitrations. (As in NC). You could probably do the same with erythritol if the nitrating mix wasn't so thick.

Justin - 21-6-2010 at 18:46

My question was would it be advantageous to use HNO3 in the nitration of erythritol instead of a nitrate salt

Microtek - 21-6-2010 at 23:54

My situation (with HNO3 vs XNO3 availability) is similar to yours, so I can give some input on the reaction: Using 18 ml H2SO4 (96%), 12 ml HNO3 (62%) and 3 g erythritol, I got a yield of 6.3 g (85 %).
The acids were mixed first, then cooled to ca. 0 C.
The erythritol was ground to a very fine powder and gradually added by sprinkling into the stirred acids, keeping the temperature under 5 C.
Stirring and cooling was maintained for 30 minutes after the end of addition, and the mix was then dumped into 500 ml of rapidly stirred ice water. Product was then filtered and washed again a few more times before being neutralized with NaHCO3 soln.
Product was then collected, dried, dissolved in ethanol and neutralised in solution by tiny additions of ammonia soln until persistent alkalinity.
Water was then slowly added with constant stirring until all product had precipitated.
Finally the collected product was dried and weighed.

I would suggest using a powerful means of motorised stirring because the reaction mixture gets very viscous toward the end of erythritol addition. I got away with magnetic stirring using a large stirbar and small reactant volume. Also adding water to the ethanol soln may not be the bes way to crystallize ETN; it gives quite flaky crystals with low bulk density (but if you intend to melt cast the ETN like I did, then that is not much of an issue).

Justin - 22-6-2010 at 03:12

Thank you very much microtek, your yeilds are the best I have seen so far, I'll try your synthesis route with the exception of a one hour reaction time and allowing the temp too come up too RT after the addition

70% conc HNO3 for nitration

Chemoxid - 5-8-2010 at 12:38

well im new in this forums and in HEs chimestry area,
but i tried this yesterday...

powerlabs MHN synthesis employ 35ml 70%conc HNO3 and 65ml H2SO4 (98%) and 1gr of mannitol per 10 ml of acid mix.

honestly my yields werent too high...after several synthesis i tried this.

40ml of HNO3(70%conc.) and 60ml H2SO4 (96% conc) and the same rule of 1gr on mannitol per 10 ml of acid.

then i added crushed NH4NO3 prills to the HNO3 till get a saturated solution, then i added slowly the H2SO4 in an ice bath and proceed with the synthesis.

the nitration was actually pretty good and yields seemed high, after recrystalization from acetone the MHN yields were higher than my others batches.

im not an expert i know that when the H2SO4 is mixed with HNO3(70%) it will react with the remaining 30% of water. so adding a soluble nitrate salt should increase somehow the ONO2 ammount in nitration bath.

quicksilver - 5-8-2010 at 13:34

MHN is not that easy to nitrate using 70% HNO3. That's simply a reality. One thing that may help is that when you have achieved a true hexanitrate you will see needle crystals. That visual que sets you on the path to getting it correctly completed.
Mannitol is much more "finicky" than many other polyols. It really wants high strength HNO3, so it's often much wiser to attempt to find some alkali metal nitrate than to continue with 70% acid.
However, there MAY be a way it could be done. The triangle graph that is related to the use of 70% acid in relation to PETN might be extrapolated to mannitol. The smartest thing is to work with a few grams due to the likelihood of getting the particulate well mixed & well exposed to the nitration acid. That is often why some materials do not scale up well. They need exposure to the acid and a smaller weight of materials allow that exposure to take place more effectively.

maxidastier - 11-8-2010 at 05:38

I tried nitration of Erythritol with self distilled HNO3 98%.
And I suggest not to le temperatures go up to RT and even MORE Important: Stirring!
I got a perfect run away in my first nitration, because I didn't stir all the time, but only every minute!

The trick, saturating HNO3 with alkali nitrate is interesting, because I won't have to distill HNO3.
But how can it work? Where is the water going to, when adding KNO3 to 53% HNO3?

@Microtek : As far as I know: If you get more than double ETN (3g --> 6,3g) then its strange.
At least not only 85% yield...
Did you test it?

Microtek - 11-8-2010 at 05:56

Quote:

@Microtek : As far as I know: If you get more than double ETN (3g --> 6,3g) then its strange.

Erythritol (C4H10O4) has a mol weight of 122 g. ETN (C4H6N4O12) has a mol weight of 302 g (dropping fractions).

So, quantitative yield from 3 g erythritol would be 3*302/122 = 7.43 g. This means that 6.3 g is 6.3/7.43 = 0.848 = 85 %.

Basic stuff.

maxidastier - 12-8-2010 at 01:02

Ok, sry, I had some other facts in my mind. You're right. Basic stuff. I should have known better.

Well, acutally, I just could'nt believe your yields.
That's totally perfect!

Do you think, we could upscale it to 9 g Erythritol?

Microtek - 12-8-2010 at 06:45

You probably could scale it up to 9 g without much trouble; A factor 3 is not that much. However, bear in mind that you need sufficient agitation as well as sufficient cooling, and with viscous reaction mixtures such as this, that can be tricky. I would advice keeping the additions slow and the temp low (extra slow and extra low).

Justin - 12-8-2010 at 19:56

On one instance i scaled up the ratio microtek provided by 20 times, using 60g ETN and following his exact procedure and got a 78% yeild. I have repeatedly used it at 10 times his scale with consistant results. So yes i would say it scales quite well. Many thanks too Microtek for his repeatable ETN synthesis using HNO3

maxidastier - 13-8-2010 at 02:10

Microtek, that's really great. I still cannot believe it, you even don't need high concentrated HNO3 e.g. 98% like for PETN, which is very similar to yours.

Do you think, 53% would also do the trick? What would be the volume in ml?

Microtek - 13-8-2010 at 13:26

You can make PETN in a similar way to this, fuming nitric isn't required. I just like using WFNA because it is cleaner, and gives a more stable product (since it is easier to get rid of residual nitric than sulfuric). I have no doubt 53 % HNO3 would work as well, but you would need a higher proportion of sulfuric to fixate the extra water.

maxidastier - 27-8-2010 at 10:45

I thougth, PETN yields are very bad with diluted nitric acid.

Microtek - 27-8-2010 at 13:18

Only if you use dilute nitric alone. If you prepare a mixed acid consisting of about 20 ml HNO3 (62%) and 14 ml H2SO4 (96%) and add 5 g finely powdered PE at a temp of 5-10 C, you will get a very decent yield (85-90 % I think, but I don't have the actual yield written down, only the procedure).
You really must neutralize the product in solution though, as traces of sulfuric acid will remain trapped in the crystals.
Also, it is very important to powder the PE as finely as possible since PETN isn't very soluble in the mixed acid. This means that large particles will only have a thin surface layer nitrated.

quicksilver - 28-8-2010 at 14:13

Of the material available via the "triangle chart" of percentages of 65-70% HNO3 used as a mixed acid in the nitration of PETN Microtek is right on the money. If you were to extrapolate that and look at ETN the issue is likely not that more complex. However there are a difference between solid alcohols in mixed acid nitration. One of the stand-outs is mannitol. It's very difficult to fully nitrate ("hexanitrate") mannitol without either a solid nitrate-mixed acid or a nearly anhydrous nitric acid.

It's actually a good "money-maker" bet, in that there are some "stand-outs" in nitric esters. Mannitol is also a complex nitration in that it does not scale up easily. The % of nitric acid must be higher than a simple multiplier of the weights at which (example 6 grams) nitrates fully. The lowest percentile may be cellulose due to the level of nitrogen available in what could be deemed nitrocellulose (I believe that 11% could still be termed fully nitrated while 13.x is possible).

Someone, possibly Jacqueline Akhavan published a list of (military & commercial products; non-research-endeavor) the highest & lowest nitrogen context, the most quickly nitrated (contact via mixed acid or Nitric alone), the most cost effective, the most complex molecule, the longest exposure during a nitration to form completed product, and the most expensive explosive to manufacture commercially (CL20; I believe). In may be that 13.3% nitrogen in NC is the most costly in terms of nitric acid in manufacturing.

see: Jacqueline Akhavan "The Chemistry of Explosives - 2001 & [Same Author] papers from Royal Society of Chemistry 1998

gregxy - 28-8-2010 at 17:45

Pentaeurethol is probably easiest to nitrate since each -OH is attached to a CH2
resulting in less steric interference. Longer chain polyols have more CH units which
I would think would be more difficult to nitrate than CH2 or CH3.

Another reason could be that partial nitrates of long chain molecules become
insoluable in the acid mix before nitration is compete.

Someone with more knowledge on nitration kinetics should be able to give
an exact reason.

[Edited on 29-8-2010 by gregxy]

Microtek - 29-8-2010 at 02:53

Quote:

Of the material available via the "triangle chart" of percentages of 65-70% HNO3 used as a mixed acid in the nitration of PETN Microtek is right on the money.

Indeed, I got the acid composition from experimentation with the little Excel macro that has floated around here. I don't recall who made it, but it is based on the triangle chart from Urbanski I think. Experimentation with that program also indicated the viability of using just 2.5 ml of practically anhydrous nitric acid per gram og PE instead of the customary 4 ml. A carefully executed experiment confirmed that a yield of about 97 % could be obtained with this method.

Rosco Bodine - 29-8-2010 at 03:41

Is this the file you are talking about ? :cool:

Attachment: petn2.xls (180kB)
This file has been downloaded 983 times

quicksilver - 29-8-2010 at 10:35

BINGO!

That .xls chart is very valuable. There are others of the same design. If I remember correctly Roscoe pointed this out several years back.
The actual research on erythritol is very marginal. There are patents and some material wherein Nobel & DuPont had a little tif over ownership. But actual research is limited. During the time when the USBoM was doing some investigation the erythritol at that time was available from natural sources and was expensive and time consuming to obtain. The "patent rights" were (IMO) more of a gesture of corporate strength than a serious effort to work with or investigate the utility of the furnished product. Superficially, mannitol took the Lion's share of the attention.

If I am correct Urbanski used the same "triangle chart" for a variety of materials. It's simplicity & utility make it ideal to determine some things from a quick visual presentation.

[Edited on 29-8-2010 by quicksilver]

Rosco Bodine - 30-8-2010 at 00:45

Attached is a paper which may be of interest

Nitration of pentaerythritol by HNO3-H2SO4-H2O system
L. T. Eremenko, R. P. Parushkova, M. A. Poryadkova and N. M. Stotskaya
Russian Chemical Bulletin
Volume 19, Number 1, 123-128,

Attachment: Nitration of pentaerythritol by HNO3-H2SO4-H2O system .pdf (1.2MB)
This file has been downloaded 1382 times

[Edited on 30-8-2010 by Rosco Bodine]

quicksilver - 30-8-2010 at 06:05

No stroke, Roscoe has taught me a great deal over the years & would honestly suggest that folks interested in this subject; diligently study the material offered (in every facet of this board). In addition; throughout the years Microtek had a method of experimentation of utilizing very small amounts of material (thus the moniker) and that has also proved extremely valuable on many levels. Many folks have some wonderful things to offer.

The only reason I digress is there have been folks around here for years that have used a great deal of creativity that I have tapped into and it helped a great deal. I continually learn from those around me and am often surprised at the level in which I understand and further this hobby by keeping an open mind and ear to the creativity & access to others. There are some [few] still contributing here but it seems that many have moved on toward professional & family commitments, finding less & less time to interact.
I am honestly concerned that this freedom in exchange of ideas & questions may not last beyond too many more years in this area. Many wonderful things come to an end and this MAY be one of the last opportunities to learn, enjoy, and maintain this hobby.

I don't mean to move so way off topic here but I had been listening to the news (& editorials) and it struck me that our world is getting much smaller. Many people - who have very different ideas of what should be freely available knowledge, are rapidly becoming more of a controlling voice. It would be a serous shame that we are the last to be able to freely enjoy such a wealth of collective discussion. -=Soapbox mode off=-

In the text "The Pentaerythriyols", Barlow, Barth, Snow 1958 American Chemical Society, the issue of acids being trapped within the crystals had been addressed and studied. It appears that NO amount of washing can rid Pentaerythriyol (and perhaps Erythriyol) of excess acid and re-crystallization (& stabilization) is really the only method for longevity and stability.
However a very unique point was made that nitromethane had been used to preform a re-crystallization with [not only] excellent results but a unique crystal structure.
There is a possibility that such a technique may lead to a more powerful energetic material. Studies during that time indicate that many if not most solvents that are used for re-crystallization may have an effect either by alteration or by retention within the crystal. Tests with various solvents show that slight but recordable changes in energetic properties exist after re-crystallization has been completed.
The text is not specific in recording that acetone results in this level of performance or MEK in that level but the alterations do exist. Trace levels also appear to exist depending upon the technique utilized. A nitromethane re-crystallization may be a very interesting (albeit expensive) experiment.

edit:
Please note that pp 57-58 offer a rather wonderful collection of re-crystallization routines that result in pourable crystalline preparations (as opposed to needles) These same techniques MAY be applicable to other polyol esters. Space & time does not permit me to outline them in depth but solvents such as amyl acetate & ethylene glycol offer key solvents for granular preparations from previously non-pourable ones (as well as offering methods of increasing density). Simple substitutions of MEK for acetone also preform alterations in crystal structure.
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).

[Edited on 31-8-2010 by quicksilver]

maxidastier - 7-9-2010 at 09:52

Quote:

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.

ETN in straight acid and proper neutralization

prometheus1970 - 13-12-2010 at 13:54

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)?

quicksilver - 13-12-2010 at 14:20

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.

DougTheMapper - 14-12-2010 at 10:05

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.

quicksilver - 14-12-2010 at 12:29

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]

DougTheMapper - 14-12-2010 at 14:54

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]

Rosco Bodine - 14-12-2010 at 17:54

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?

DougTheMapper - 14-12-2010 at 21:19

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]

maxidastier - 14-2-2011 at 09:52

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?!

Rosco Bodine - 14-2-2011 at 10:59

Try the Darwin Awards committee, maybe they can help on that melt purification.

maxidastier - 14-2-2011 at 11:39

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 694 times

quicksilver - 14-2-2011 at 16:33

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.

Rosco Bodine - 14-2-2011 at 18:52

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 842 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]

maxidastier - 15-2-2011 at 09:03

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 :mad:

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]

Rosco Bodine - 15-2-2011 at 11:03

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.

Contrabasso - 15-2-2011 at 13:12

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.

Rosco Bodine - 15-2-2011 at 13:42

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.

quicksilver - 15-2-2011 at 14:05

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]

Rosco Bodine - 15-2-2011 at 15:28

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]

maxidastier - 16-2-2011 at 04:58

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?

Rosco Bodine - 16-2-2011 at 08:04

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.

maxidastier - 17-2-2011 at 05:19

Ok, so if you had got the acid mix from making ETN, what would you do most likely apart from draining it?

Rosco Bodine - 17-2-2011 at 06:13

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.

quicksilver - 17-2-2011 at 09:08

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]

Rosco Bodine - 18-2-2011 at 01:54

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]

maxidastier - 18-2-2011 at 06:09

It's like a curse. I cannot get any Napthalene in Germany! Can you?
What about urea to nitrate to ureanitrate?

Rosco Bodine - 18-2-2011 at 10:06

You have to lose the sulfuric acid first on that one, precipitated as gypsum, by
a partial neutralization with lime, and then filter and neutralize the residual nitric acid with the urea and evaporate the solution to crystallize the UN, but there would be no acid recovery whatever as reusable acid going that route.

maxidastier - 19-2-2011 at 14:13

Quote:

but there would be no acid recovery whatever as reusable acid going that route.

You mean, I don't have recovered acid at the end?
I wouldn't care about that if at least there was some use for it...

However, I don't know if there are other materials that could be nitrated in that waste acid mix.
Maybe there's something that strips off some more nitrogen to enhance the efficiency? (Apart from toluene, starch/cellulose and Napthalene)

[Edited on 19-2-2011 by maxidastier]

mabuse_ - 22-5-2011 at 00:35

One more question:

The nitration process itself is exothermic.
To my knowledge the only other exothermic reaction whould be carbonisation of the erythritol.
Temperature during my last experiment did not exceed 25°C, so I guess that no significant carbonisation ocurred.

Can i deduce that my nitration isn't finished from the fact that the slurry still generates heat?

quicksilver - 22-5-2011 at 06:09

Not entirely. The measurement of heat would need be taken over a protracted period of time and with that time, contact of the mixed acid would complicate the results. Remember that the solution is now at a much greater density & w/ that density comes a slower level of cooling.
However; the generalist picture is the "heat produces inefficiency" in esters. It's also a warning sign. Working toward a colder synthesis is generally safer and more productive with esters. A "cap" of 25 C is (IMO) a higher end of safety and efficiency. Effective stirring, command of lower temps and efficient contact is often the ideal. I believe that the question is very logical but complicated by conditions in nitric ester synthesis.

Different solid nitrates to produce a HNO3 have ranges of productivity. Leaving that aside, the use of that technique demands a complete solution of the nitrate within the H2SC4 and a lowering and maintenance [of a low temperature] ( along with "stir-contact") to be as effective a synthesis as possible. Yield weight & crystal format [from re-crystallization] is a useful indicator.

Precursor addition speed & weight can control a great deal of the esterifaction. Do not attempt to recover acids; it's never worth the risk. Enormous research have been attempted toward that end; many tragedies resulted in certain conclusions. Benzene-ring nitration's are not nitric esters.

Please note that the above is opinion based on observation & selections in Federoff.

[Edited on 22-5-2011 by quicksilver]

mabuse_ - 29-5-2011 at 04:42

Thanks for your answer.

I know it was pretty warm, but i wanted to speed it up a little.

Yield was about 65g from 50g Erythritol (after recrystallisation, so not very meaningful).

Problem is that my improvised magnetic stirrer will not handle such viscous stuff and hand stirring for an hour or longer is rather exhausting

When I discontinued stirring for some time, resuming whould cause a significant temperature jump, about 2-4°C, and noticeable gas emission.
Perfect stirring would be an tremendous improvement.

I'm planning to get a proper magnetic stirrer, but i guess even these machines won't handle this task.

quicksilver - 29-5-2011 at 05:43

There are some cute "tricks" to using a magnetic stirring device with thick material.
Starting and stopping (the stirring process) may result in oxidation of the precursor via heat, etc - in a greater % than expected. That and temp in general is one of the most important things about utilizing one (AND having a good selection of stir-bars). There are many designs for stirring devices.
Some member have made them for very little money and the result were supposedly fantastic.