Sciencemadness Discussion Board

ETN synthesis problem

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The_Davster - 25-11-2006 at 15:06

Whoa... 2 in an hour.

Chemolobotomy seems to be a reincarnation of If_6_was_9, and other guises. I deleted some posts that were in completly wrong threads, but they keep coming. Same crap as usual.

Lassofix is some sort of spambot, post left in detritus currently.

[Edited on 21-12-2017 by Bert]

vulture - 25-11-2006 at 15:14

10-4, both have been banned as of now. Thanks for reporting this.

ETN synthesis problem

Deceitful_Frank - 13-12-2006 at 11:31

Hey guys, just a quick question concerning the synthesis of ETN using erythritol, ammonium nitrate and sulphuric acid.

The ratios that I use are 1:4:12 but mass but towards the end of the erythritol addition to the mixed acids, everything becomes so thick that the whole deal is VERY difficult to stir with broken thermometers and partially nitrated shit being the result!

Does anybody know of an "inert" liquid that I could add to the reaction mix to thin it all down, make it easier to stir and promote homogenuity and give me a purer end product?

...sure I could just use more AN and acid but Ime not keen to waste my chemicals unnecessarily and dont want to lose any more ETN to dissolution in the acid bath.

Any help or ideas would be gratefully recieved,

Regards.

ZoSo357 - 13-12-2006 at 12:16

How cold are you keeping your nitration bath? Many people have had best success around 15 - 20* celcius. A slightly warmer bath should keep it a little less viscous.

Deceitful_Frank - 13-12-2006 at 12:46

Good point! I usually work between 5 and 10C... Deffinately worth a go though I do work indoors without a great deal of ventilation and when my nitration bath has topped 20C, the HNO3 mist can become a little trying!

hinz - 13-12-2006 at 15:25

I would simply buy a destillation setup and work with pure nitric/sulfuric mix, a basic destillation setup simplifies so many things, it's really worth it's money.
If not, you might also mix your nitration acid with some methylene chloride, it should be inert against it, as it's used to seperate HNO3 from water, but I don't know anything about the solubility of ETN in CH2Cl2, so maybe CH2Cl2 dissolves some of the product which has to be removed afterwards.
After my attemps to nitrate nitromethane to tetranitromethane (attack of NO2+ on CH2=NOOH <=> CH3NO2, when the aci form deprotonates, CH2 might have a negative charge) I think NM is also stable against HNO3, my mechanism somehow doesn't work. So it might be used to thin your mixture (ofcourse in absence of an aldehyde or ketone;) ). But it will increase the explosion hazard. polar stuff like pentane you can forget because they are inmiscible.

[Edited on 13-12-2006 by hinz]

quicksilver - 13-12-2006 at 18:58

Bringing the temp to 15-20 C is a great place to start. The common issue encountered as you describe is that if nitration is successful (re: yield) you should have a thick mass - thus your nitration is successful. The most important issue is to make sure to elimininate hot spots via stirring of course. If you are using a magnetic stir-bar, often the size is too small to be of much use when the solution is thickened. A significanly thicker stir-bar would take care of that as well. However some of the methods used to deal with the issue has been to use HNO3 at 70% as an additional element to make stirring successful. If that (HNO3) is not available and additional equipment is also not available, a longer time frame in one's additions MAY make the solution mixable as temp maintains itself at 20 C. But to address the question directly; there is no reason why one has to attempt the highest yield per ratio. Meaning that you could simply use more nitration acids in ratio to eurythritol.

Here is some stuff...hope it helps

[Edited on 14-12-2006 by quicksilver]

Attachment: ETN_notes-2006.pdf (48kB)
This file has been downloaded 8914 times


ZoSo357 - 14-12-2006 at 14:15

Hinz, Something that (may be unsual) yet tends to be a problem with HNO3 and H2SO4 is that many people have trouble getting a good nitration for ETN. Their yields tend to turn out worse than with a nitration using a nitrate salt and H2SO4. From what I've read about people on APC forum, and my experiences, the best way to get ETN to nitrate and give you the best yield during your precipitation is to use KNO3 and H2SO4.

Yeah, the KNO3 will be a little thicker and harder to stir than NH4NO3, but the end product has been more efficient in precipitating out larger amounts than with NH4NO3 or HNO3.

I'm not sure of the exact reason why, since this tends to be the opposite with things like nitrocellulose and other nitrateable compounds(nitrating more efficiently with ammonium nitrate as a salt, or with pure HNO3), but there's a discussion of ETN synthesis on the *old* APC forum pertaining to the issues people had with nitrating erythritol.

Goodluck deceitful frank.

[Edited on 14-12-2006 by ZoSo357]

quicksilver - 14-12-2006 at 17:16

You know you bring up an interesting point; the nitrate salt. A few people have done some testing w/ different nitrates but the one thing that many folks don't do is reduce the particulate size to start out with. From what little experimenting I have seen, if the particulate is sub-sieze in size to begin with a heck of a lot of problems are reduced (pun intended). Another thing that stands out as a variable w/ many experiments in nitration w/ solid nitrates is that either the H2SO4 or the nitrate may have impurities to begin with. However alk metal nitrates often have advantages in some nitrations. I know that a search in the forum here would turn up some info on that very subject. The question I have often wondered is IF there is an optimum solid nitrate for specific nitratied materials. And there does appear to be some substantiations for using differing solid nitrates.
IIRC some of the best yields with ETN have been HN4NO3 nitrations re-crystalized with methanol. Often what is delivered prior to re-crystalization can be outstanding. That is not to say that Na or KNO3 would do better; one would need to simply work with a given gram size of starting material and actually weigh it when totally dry. Occationally those yields are diminished during re-crystalization. Acetone appears to be just TOO an effective solvent for ETN with the end result being crystals that are irrregular platlettes which are much less dense than w/ the use of an alcohol as solvent. The lack of density makes for poor preformance as an energetic material when compaired to a dense granular crystal.
I have a lot of info on ETN and if I can dig it up I'll post it to this thread (if it keeps on going). Most all the stuff I had thought was ever done was hobbiest stuff during the last few years BUT....there was some stuff DuPont did during the patent application period. And interestingly enough a lot of it had to do w/ re-crystalization ....

[Edited on 15-12-2006 by quicksilver]

Deceitful_Frank - 15-12-2006 at 14:15

Of course, distilling pure WFNA and using this to nitrate my erythritol and then precipitating with sulphuric acid is the most efficient route to highly nitrated ETN of good stability and in great yeild but at present, in the absence of the glass, the space and the means, the acid/nitrate method cannot be ignored for its simplicity. Crude and tedious albeit, ime sure that if all minor creases can be ironed out, we could have a good honest no-fuss route to ETN.

For now I think I will scrap the idea of trying to water down the nitration as like quicksilver stated, the very fact that my nitration thickens up stiff proves the production of highly nitrated erythritol thats insoluble in my nitration bath! I suppose it depends where my priorities lie... do I want to get the maximum ETN per erythritol or do I want to conserve my somewhat limited quantity of acid and ammonium nitrate. Hell maybe I just want maximum nitric ester per cash spent on reagents!

Fortunately I have nearly a kilo of erythritol so never likely to run out any time soon. I use cheap-ass drain cleaner of 95-97% purity and full of red dyes and shit. Although it severely gunges up my EGDN and lowers yeilds, it doesnt seem to contaminate or get in the way with ETN synths... plus its OTC and after a recent close call with the law, Ime keen to save my hard-won clear 98% reagent grade acid for the experiments that REALLY need it!

This leaves the question of ammonium nitrate. It would appear to be my most difficult to acquire reagent for this synthesis as I have no OTC supply and internet sales of the compound are watched by the government. Ive managed to "find" 7Kg but with so many uses it seems apparent that it would be wise to design a synthesis for ETN that gives the highest yeild of nitric ester per gram of ammonium nitrate used.

So taking my original numbers of 1, 4 and 12 by mass which gives approximately a 50% excess of nitric acid than is need to fully nitrate the erythritol plus a mole of sulphuric acid to mop up every mole of water produced by the esterification... and a little extra to thin the whole deal down a bit. Could I maybe reduce the ammonium nitrate to 3 times the mass of the erythritol and get a good yeild with just a 15% excess of nitric acid or is this going too far?

Maybe I should stick with those original ratios and to thin it all down, just increase the quantity of my cheapest and easiest to acquire reagent, the sulphric acid?

Either way, I have found what appears to be the perfect way to recrystalize raw ETN (with a view to remove lower nitrates, acidity and give larger, easier to handle crystals)

I use generic methylated spirit from the hardware store. Mainly ethanol with methanol, pink dye, bitrex and a small amount of gasoline added. I think the gas is there to prevent it mixing with water and to make it nigh on impossible to distill out the ethanol for consumption. Therefore it isnt taxed and is very cheap to buy.

Basicly all I do is add the dried, raw and neutralised ETN to a small amount of meths in a sealed glass bottle (trial and error needed) and heat to 55C to dissolve (dont let it go over 60C or the ETN will melt or precipitate as a liquid... then its FUCKED!)

When its all in solution and around 55C I take the glass bottle and place in a LARGE jar or hot water at around 57-58C and leave the whole lot to cool very SLOWLY. the ETN precipitates nice and slow into large crystals of much higher bulk density than when in the raw newly nitrated state. And so into the freezer to get the last ETN out of solution and hopefully leaving the more soluble lower nitrates behind dissolved in the meths :D


[Edited on 15-12-2006 by Deceitful_Frank]

[Edited on 15-12-2006 by Deceitful_Frank]

quicksilver - 16-12-2006 at 06:27

Re-crystalization is a key issue with PETN, ETN, MHN, etc - The reason I mention the fact that methanol will work in that capasity (w/ ETN) is that it is available OTC via auto supply stores..... The more one maintains simplicity in experiments the better chance one has for "all the creases being ironed out"....Thus there will be no complications with bizarre and extrainious stuff left in your ETN at the end of the synth.....when you get really pure ETN in course, heavy, well formed crystals; it is some very interesting material, indeed.

Sickman - 16-12-2006 at 23:26

This is a good topic!

I've been hearing people complain for years about thick nitration mixtures and broken thermometers and so on.

I really don't know what the ultimate answer is. On the one hand if you add an inert solvent you are diluting your acids, which may result in poor nitration, low yield and the need for longer nitration periods. On the other hand concentrated nitric acid may be the answer, but it is not always the best choice in a given nitration such as for erythritol, because of lower yields, problems with oxidation of the erythritol and higher costs for the acid.

Thus far what has worked best for me is to ditch the glass thermometers for a good plastic cooking spoon. They don't break and the plastics I have used have been completly inert to the reaction. In combination with the plastic spoon a much longer nitration period could'nt hurt much in the case of ETN.

Because the ETN nitration using alkali metal nitrates and even AN is very thick like icing, a plastic spatula may prove to get the mixture mixed the best if a mechanical help is not available.;)

If you are a wealthy fellow, unlike some of us, the answer is obvious. Use a greater acid/nitrate to erythritol ratio, but who among us is a wealthy fellow?:D

On a similar note: has anyone noticed a difference in final yield when the acid and nitrate is first mixed and then the erythritol is added to it, as opposed to adding the erythritol to the sulfuric acid and then adding the nitrate to that. Upon studying Urbanski a bit I see that order of addition does matter in many cases. Urbanski noted that adding the substance to be nitrated to a mix of acids can result in higher nitration than first sulphonating the material and then adding the nitrating agent to that, (unfortunatly this can also lead to oxidation of the material to be nitrated causing lower yield IMHO). The reason is he explains is that the material being nitrated will have far more contact with the nitration agent in a much higher concentration, as opposed to a more isolated environment were only a small amount of nitratable material is in contact with the nitration agent.

However, first sulphonating the material to be nitrated, for example phenol, in the case of picric acid, has many benifits including easier nitration and less oxidation.

I wonder if there can be a happy balance. I think I might try simply mixing a pre-calculated amount of powdered erythritol with powdered AN and then add the powdered mix directly in portions to the sulfuric acid. Who knows a little tinkering around with ratios and orders of addition may lead us too the highest nitration levels, lowest oxidation of erythritol from the nitric acid and highest yields.

quicksilver - 17-12-2006 at 10:38

"On a similar note: has anyone noticed a difference in final yield when the acid and nitrate is first mixed and then the erythritol is added to it, as opposed to adding the erythritol to the sulfuric acid and then adding the nitrate to that. Upon studying Urbanski a bit I see that order of addition does matter in many cases. Urbanski noted that adding the substance to be nitrated to a mix of acids can result in higher nitration than first sulphonating the material and then adding the nitrating agent to that, (unfortunatly this can also lead to oxidation of the material to be nitrated causing lower yield IMHO). The reason is he explains is that the material being nitrated will have far more contact with the nitration agent in a much higher concentration, as opposed to a more isolated environment were only a small amount of nitratable material is in contact with the nitration agent."


This is a very important issue. Does this issue have more relevence to a phenol than a solid alcohol? It would seem to be a damn good experiment for a solid alcohol. From what I have read not all nitric esters react the same during nitration. This concept (addition to HNSO4) would not make a significant difference with glycerin I believe but with mannitol or sorbitol it is manditory for good results. Erythritol nitrates very easily; that is shown by the speed of crystaline build-up during the addition phase. However, if one has taken care to be thorugh when creating a nitration acid mix (making sure that the solid nitrate it totally dissolved in the HNSO4, covering the beaker with Al foil to prevent fumes, high oxcidation rate, etc & achieving a clear solution) and one's additions are at a CONSISTENT level, the build-up of heavy crystals should only occur at the end of the nitration. Best yields and best control oveer the nitration are achieved if the nitrating acid is clear, cold and the additions are consistent in time margin and weight.. ... Where there has been issues often can be traced back to inconsistency to temp and addition time/weight ratio. There is a great book (if you can ever find a coy BUY IT!) intitaled "MILITARY EXPLOSIVES" by Weaver, published by Wiley in 1906. I have seen a copy from 1917 (4th edition) wherein the actual nitation machines used by DuPont are illustrated and discussed at length. They didn't leave the ratio weight/time addition to chance as it became critical to yield, safety, and control of quality. Where I am going with this is that IF that nitration acid is COLD, just out of the 'fridge and the additions are consistent, the acid should warm during the peak of crystal production and lower it's viscosity enough due to warmth (20C) to be mixable without great difficulty as the yield has peaked. With ETN, once the yield has peaked the material should sit for a period of time in cold (no hot spots) and the bearing of a 70% or greater yield should maintain itself on the correlation of those above illustrated issues.

Sickman - 18-12-2006 at 01:16

Quicksilver,

The book you mentioned can be read online at:
Notes On Military Explosives by Erasmus Weaver

You can also download a free PDF file of the book at:
Notes On Military Explosives by Erasmus Weaver PDF

70% yield is not that great in my book. In my mind the possible culprits inhibiting a higher yield may be:

1. Oxidation of the erythritol by the nitric acid due to the acid being too concentrated or nitration temperature being too high may also cause oxidation to occur.

2. Incomplete nitration due to lack of sufficiant nitrating agent and a need for longer nitration periods. The loss of fixed nitrogen in the form of nitrogen oxides (brown gas), often due to excessive heating of the nitration bath also falls into this category of loss.

3. Problems with solubility, including incomplete crystallization of ETN from the nitration bath. This problem may be solved by salting out of the ETN by adding an additional amount of ammonium sulphate or any other salt, preferably a sulphate, that would be more soluble in the nitration bath than the ETN is, after the nitration process has been completely resolved.

4. Careless filtration and recrystallization methods.

I find it unlucky that nitric esters have so many stability problems, with PETN, and perhaps ETN also, being the most stable of the bunch.

As far as order of additions in manufacture of various explosives goes, the optimum order of addition will depend on how susceptible the material to be nitrated is to oxidation and the fact that first sulphonating the material often makes it easier to introduce the nitrogen groups by way of reduction of the sulphonated groups. The nitration of phenol is a good example of this trait.

I've learned that each nitration is unique; each has it's own necessities to be met for best performance and safety.

a_bab - 18-12-2006 at 04:08

Sickman, the link doesn't work anymore. Can you uplod the book somewhere else please?

quicksilver - 18-12-2006 at 10:20

Here is some more info patents, pics; it picked up where the other PDF file left off...


** That link for Weaver worked for me just fine...(?)



[Edited on 19-12-2006 by quicksilver]

Attachment: ETN-pics-Lab-pat.pdf (562kB)
This file has been downloaded 8236 times


maxidastier - 3-4-2010 at 08:26

hello,

I'm just having one only question: Can I use Soda instead of Baking Soda?

hissingnoise - 3-4-2010 at 09:04

The only thing I have against washing soda is its basicity. . .
Doesn't every home have some baking soda lying around?

maxidastier - 3-4-2010 at 09:15

But do you think those 50 g packages are enough?

hissingnoise - 3-4-2010 at 09:34

How many tons of nitrated material do you intend producing?

But seriously, amounts of bicarbonate needed for neutralisation are very small if you've washed your product with water first.
5% solutions are fine!



[Edited on 3-4-2010 by hissingnoise]

quicksilver - 3-4-2010 at 10:20

If you re-crystallize with commercial ethanol (Everclear, etc) you will have a 95% - 5% H20 solvent. The small percentile of water will maintain the anti-acid product so as to make that available to the crystal. There is ETN, MHN, etc hanging around for years - as bright and pretty as the day it was made.

maxidastier - 3-4-2010 at 12:02

Really? Why do so many get high yields with the commerical Ethanol?
I have distilled my own METHANOL, so I get only around 90%.
Do you really think that's waste now? I have some 50 g ETN to recrystallize, please don't tell me it won't work....:(

[Edited on 3-4-2010 by maxidastier]

quicksilver - 4-4-2010 at 09:13

Methanol is fine - no problems. The issue is that commercial ethanol has a small % of water and anti-acids (such as bicarbonate of soda) is very soluble in water. Thus when you re-crystallize, you have direct application of the anti-acid with the crystal. This is not to say that less soluble material (solvents) to anti-acidic products won't neutralize your material. However the level of neutralizer is available with a fraction of water within the solvent.

IF however your methanol has a fraction of water - you should notice that your bi-carbonate should dissolve within better than anhydrous solvent materials. The idea is to completely wash until neutral, re-crystallize with an anti-acid (& best, w/ a stabilizer) thus maintaining a synthesis that won't give way to existing acids lurking about.

Some materials require a continued wash is a desired shelf life of many years is anticipated. Most notably NG. I believe that some of the oldest nitric ester in existence is NG but it required a wash periodically through decades. properly synthesized, the majority of nitrated polyols will last quite a long time if kept from acid, UV, heat (>40 C), etc.

[Edited on 4-4-2010 by quicksilver]

grndpndr - 4-4-2010 at 19:41

Automotive 'Heet' , (yellow bottle methanol AIRC)MSDS lists content as 99% methanol,.02 xylenes,0-,m-,p- isomers)
Unknown % corrosion inhibitors.Might need add little dist water to incorporate the bicarb.:)Urea a reasonable stabilizer?If that could be incorporated at some point particularly during a recrystaliztion the urea etc, should be incorporated consistently
thruought?

[Edited on 5-4-2010 by grndpndr]

quicksilver - 5-4-2010 at 08:08

Urea, Betain, Diphenyamine all work fine as a stabilizer. The prime factor is getting it into the material instead of superficially covering it.
Most of the time, if the synthesis has acid lurking about - it will be noticed. However, there ARE materials or conditions that do a good job of disguising the impurity.
Most nitric esters become a problem when they decompose. At the turn of the 20th century, paper with various indicators were often included in packages of commercial energetic materials. Any white paper in contact will change color if the acidic impurity is high enough. Occasionally they had been constructed so that it would not be immediately apparent that they were there as a "problem indicator" (printed advertisements, etc) so as not to frighten the buyer. However the large commercial powder salesman would know and dump his samples (or whole order) if they showed a problem. In the heat, poorly made products had problems surface quickly & the results could be calamitous.

A pretty interesting book printed by the ISEE is entitled "Explosives -100 years Ago, More of Less", Hopler. It has some unique stories and advertisements in it. That was the same time in history that many of the synthesis that are talked about here were the popular level of science!

maxidastier - 11-4-2010 at 04:51

I'm wondering how many solvable non-ETN material is in the mix.

I prepared some ETN with 20 g Ammonium Nitrate, 25 ml H2SO4 and 5 g of Erythritol.
After four hours of reaction I dumped the thick cream in around 150 ml of ice cold water.
Everything got cloudy, but I realized some stuff at the bottom, that only dissolved after stirring.

After filtrating it and drying a little bit, it was 37g! I thought, uh! This won't be all ETN, with only 5 g of Erythritol used.
Well, the next day I weight it again, more dry now, and it was still 32 g!
So I dumped it again into some cold water and neutralized with baking soda. It needed only some 0,5 gramms of it and it was then neutralized. Lots of ETN was smimming on the top.
I filtrated it and was shocked, that it had lost so much weight. First 32 g, now 20 g.
And I even hadn't recrystallized it.
But I did that an hour later, adding the stuff to some 50 ml of hot Methanol. It was so cloudy that I didn't see, if everything dissolved, but it should be most of it.
Well, after cooling it down in the freezer, filtrating it and drying it, I was REALLY shocked :o
Guess, what was left of ETN? 4 GRAMMS :mad:

I can't believe it yet, and I'm asking you: Was the rest of those 32 g some other stuff or what was my mistake?
Because 4 g ETN from 5 g Erythritol is more than a poor yield.

PS: I'm German, so don't blame me for my English..

[Edited on 11-4-2010 by maxidastier]

[Edited on 11-4-2010 by maxidastier]

[Edited on 11-4-2010 by maxidastier]

quicksilver - 11-4-2010 at 06:05

Quote: Originally posted by maxidastier  
I'm wondering how many solvable non-ETN material is in the mix.

I prepared some ETN with 20 g Ammonium Nitrate, 25 ml H2SO4 and 5 g of Erythritol.



It's a tough question because the ammonium nitrate (if from fertilizer) could have clay, dirt, & other nitrates.

The fact that you got a low yield is occasionally due to oxidation from too long a time exposed to nitration. Strange, yes - but it's happened too often not to be a factor. Proper time exposure is often a trial & error issue. Try one hour total & see if it happens that you don't get a better result.

However if the ammonium nitrate (or anything in the synthesis) has impurities then the reaction has a variable in it that cannot be responded to be an outside answer. Purification is in order, if you suspect that issue.



[Edited on 11-4-2010 by quicksilver]

gregxy - 11-4-2010 at 13:34

I had similar problems with ETN, initially there is a lot
of "solid material" formed from the nitration but a lot
is lost during the drowning. My AN seemed to be fairly pure,
there was no water insoluable material in it when I started. My thought was that the ETN contained a large amount of
di and tri nitrates which are fairly water soluable.

maxidastier - 12-4-2010 at 08:55

It's really annoying now.
My forth synthesis with the same result:
5 g of Erythritol didn't give me expspected 9 g ETN, but only 4 grams again.

I followed your advice and only used a nitration time of one hour with stirring every 5 minutes.
I dumped it again in 200 ml ice cold water, filtrated it and then dumped it again in ice cold water to completely neutralize it with baking soda. It needed nearly 45 g of baking soda until CO2 bubbling stopped (is that normal?)
The last synthesis with longer nitration time needed only 5 g of baking soda to be completely neutralized...

Well, I dumped the stuff in some hot methanol until dissolved, discovering some material on the bottom that didn't dissolve (what was that?) So I first had to filtrate that again.
Then I cooled it down, very slowly.
The next morning everything was full of recrystallized ETN.
I thought, that had to be at least 8 grams, but again, I was shocked after filtrating it.

Again only 4 grams ETN from 5 g of Ertythritol?

What is wrong?

maxidastier - 12-4-2010 at 10:06

Recrystallization seems to be one key issue.
The nitration shouldn't even be so short.
One might only add so much boiling methanol until everything dissolves. NOT MORE! Otherwise much of the ETN won't get out of the mist anymore.

hissingnoise - 12-4-2010 at 10:49

AN, because of its hygroscopicity needs to be dried thoroughly before use and H2SO4 needs to be 98%.
AN can *look* dry while still retaining considerable moisture but if you want 10gms of nitrate from your 5gms of sugar, use mixed acid!


rbick - 12-4-2010 at 11:58

You used 20g AN to 25 ml of Sulfuric? This seems to be a lot of AN. When I prepare a nitration bath using a nitrating salt for ETN (It seems to give me excellent yields using this method), I use 55g AN to 100 ml Sulfuric.

I have done dozens of ETN synthesis and this ratio seems to optimize my yields. I actually have a pile of ETN drying right now. I used 200 ml sulfuric to 110g AN. I added 35g Erythritol and have a yield of ~45-50g. Both chemicals used are ACS grade.

Maybe try similar ratios for your nitration bath and see if that makes a difference?

Also what maxidastier said with recrystallization; I had problems with adding too much ketone/alcohol which decreased the yield. Be cautious with adding it, making sure you don't use too much. The stuff you saw that didn't dissolve was probably un-nitrated erythritol or other impurities. Its a good thing to filter those out, another positive result of recrystallization.

Anyway, hope it works out. Good luck!

EDIT: Just so you guys know my ETN is legit ;)



[Edited on 12-4-2010 by rbick]

maxidastier - 13-4-2010 at 07:51

Well, thankfully I kept that stuff that didn't dissolve in the methanol.
Although I couldn't believe that it would be useful later, it IS now!
It really is ETN, that didn't "want" to dissolve. It is no waste stuff, strange,
but I made some tests with that "stuff" with my hammer :D an it IS ETN. ;)
I'm wondering how it can be, that it didn't dissolve although I used TOO much of Methanol :o

rbick - 13-4-2010 at 17:28

Maxidastier: I noticed something interesting today. Your problem motivated me to look back at lab notes and do an experimental ETN synthesis.

Looking back it seemed yields were lower when I kept the nitration at temperatures around 10*C but increased when I let the mix get around 20*C or even a little higher. Today, I made a nitration mixture with 100 ml 98% sulfuric and 60g purified AN. After dissolving all the AN, I put the nitration vessel into an ice bath and let it cool to 10*C.

Before I continue I forgot to mention something I read back on roguesci before it closed down: YOU HAVE TO READ THIS: http://pubs.acs.org/doi/abs/10.1021/ja01681a501

It talks about the dehydration of AN in Sulfuric Acid when it reaches a certain temperature, which means it produces more gas than nitric acid. Read it for details, its interesting.

So anyway; I added the erythritol to my nitration mix slowly over about 10 minutes maintaining 10*C. After adding all of it and letting it sit with occasional stirring for 15 minutes, I noticed the mixture wasn't that thick with ETN crystals. I removed the nitration vessel from the ice bath and let it get up to about 20*C. I then let it sit for an additional 15 minutes with stirring. In the 15 minutes, the mixture became thick with crystals, almost to the point of breaking my glass stirring rod. I filtered it and washed it with bicarb. I didn't recrystallize since I'll be dissolving it in NG and NM for some fun experiments, which I'll post later! :D

SO in conclusion: Could it be coincidence? Possibly, but try letting the temp get up to 20*C, maybe even a little higher and see what happens if you haven't already. Making ETN usually seems to result in a mild nitration without too much threat of runaway, but be careful anyway. Hope this helps.

[Edited on 14-4-2010 by rbick]

maxidastier - 14-4-2010 at 02:50

You only had an nitration time about 20 mins?
Won't that result in a low yield?
Because I realized: A nitration time about 6 hours, mentioned in the pfd to be optimum, seems to nitrate everything, but maybe not only Erythritol.
Because at 6 hours I need very les bicarb to neutralized, while at a time about an hour, it takes much longer to neutralize...
Well, my syntheses yesterday was very warm, maybe to warm, because it got very yellow (NOx).
My last synthesis was at about 15°C but yield was only 6 g ETN from 5 g of Erythritol.
Is still don't know what's my mistake...

rbick - 14-4-2010 at 04:40

Well jeez I don't know whats going on then :o! Since I had to let it warm up to 20*C and waited an additional 15 minutes, the nitration time after all of the erythritol addition was roughly an hour. The yield was pretty good. Haven't measured it yet but its appears to be over 20g from 15g of erythritol.

Read that article I put a link to. If your AN/Sulfuric nitration mix gets above a certain temp during AN addition, very little Nitric Acid is created. That might do it, who knows. Good luck.

maxidastier - 14-4-2010 at 06:29

oh my god...One hour earlier I prepared a new synthesis and followed your tips with only 20 mins of nitration.
Damn it, why didn't you write that it was one hour, because that's also the way I normally do it...:(
Well, on that link I can't see an exact temp.
I kept my nitrate salt/ sulfuric mix at very low temp in ice bath, so I think it produced enough nitric acid.

But: This synthesis will be waste with only 20 minutes of nitrating :(

gnitseretni - 14-4-2010 at 07:45

When making PETN... a minute or so after all the PE has been added, I place the mixture in a hot bath(40-45C). It increases yield. Perhaps the same goes for ETN?

maxidastier - 14-4-2010 at 07:46

A nitration time of only 20 mins seems not to lower the yield...

maxidastier - 15-4-2010 at 05:56

No, i don'T think this goes for ETN. When I once let it get over 30C it got very yellow (maybe the NOx)

rbick - 20-4-2010 at 10:21

30* is way too high and the yellow color is the ETN decomposing and the presence of NOx fumes. I would say max 20*C is a good idea.

Still having trouble with the synthesis? What grade chems are you using?

quicksilver - 20-4-2010 at 15:04

I can only underline rbick's statement. 30 C is really pushing it. However I am also quite aware that yellow as a consistent color (no alterations) may have been an altogether diffing phenomenon if any TNP had been exposed to lab ware - such is the nature of the dye.
What's more, the measurement of time within nitrating must be "on the same page". Is that a total time allotted for addition or the time wherein all the polyol has been added and from that time to time of quench (or elimination of acid by other means)???

If the twenty minute time frame is from start of addition....it would seem rather short. However, from total time where all the material is exposed to HNO3 or mixed acid there is some interdependency on weight. If you are dealing with a few grams (5), it may suffice.
There appears to be some level of higher yield when ratios of acid increase, purity issues surface, & exposure is enhanced by continued stirring.

There are quite a few factors that are difficult to take into account when discussing a procedure that is not witnessed or exacting notes are unavailable.
There has been recorded a differing yield from nitration wherein polyols are dissolved in high strength nitric acid and sulfuric is added to that to precipitate yield. There are others that benefit from mixed acids as a continuum. Factors influencing nitration may be quite a few.

1. Time frame of addition
2. Weight of material
3. Ratio of acid(s) to nitrated material
4. The material itself
5. Type of nitration (nitric 1st then sulfuric, solid nitrates, mixed acids, etc)
6. Strength of nitric acid
7. Condition & type of nitrated material
8. Temperature of both material & acid (& alteration of temp)
9. Surface area of nitrated material
10. Speed of addition of nitrated material
11. Contamination of material, acid, or vessels

So you see that with at least ten areas of variance, there is a Hell of a lot of room for issues altering the result. The early plants and factories spent a GREAT deal of time on consistency alone. as the lack of consistency cost a great deal in profit, safety, & utility.


[Edited on 20-4-2010 by quicksilver]

DougTheMapper - 21-4-2010 at 16:49

I have a quick question while we're on the subject -

I know ammonium nitrate seems to be the best nitrate salt to use in this synthesis in conjunction with sulfuric acid. However, sodium nitrate (and potassium nitrate) are much more readily available. Weight for weight, sodium nitrate contains almost exactly the same percentage of the nitrate group (you'd need about 7% more by weight than NH4NO3), not to mention that sodium sulfate has half about the solubility in water as ammonium sulfate, which could potentially keep the yield up.

Sodium nitrate is available for as little as $3 per pound from certain sources.

So why not use sodium nitrate?


[Edited on 22-4-2010 by DougTheMapper]

quicksilver - 22-4-2010 at 06:20

- It will be fine provided you take certain steps. And this applies not just to NaNO3. The alkali nitrates will mostly function well in that capacity.
The issue generally is the FORM available. If using fertilizer grade materials there are often coatings of clay and other materials that make moving NaNO3 into a solution more difficult. IF you have a good supply of one or the other, it's often a great idea to re-crystallize the material to eliminate the impurities and make it easier to mix w/ H2SO4.

At minimum, crush the prills into a very fine powder prior to mixing into solution. You can also determine IF you have a source with impurities by working a solution of NaNO3 w/ water and determining if you see the clay. If so, [to not re-crystallize] will invite a poor synthesis.


[Edited on 22-4-2010 by quicksilver]

maxidastier - 22-4-2010 at 10:02

Well, I used different ratios and different nitrates (KNO3 and NH4NO3)
My last synthesis was from http://n3chem.freehostia.com/?p=ETN, but it it was hard work with only the same yields as my other synths. I got 12 g ETN from 7,5g Erythritol. All my synths were like this.

Can one tell me the ratios with KNO3 and NH4NO3?
We need to try out different ways if making ETN, because ETN is a very good, strong HE, close to PETN but way easier (or not ;)) to make (if you don't get PE)
The best thing about it is that you can melt it easily and dump it into casings, reaching a very high density, resulting in perfect velocity!
I made tests with small amount of ETN in foil and hit it with a hammer. Made nice boom.
But then I made the same with molten ETN. Well, I would be deaf, if I didn't wear ear protection...:cool:
Perfect booster, too...

But synthesis and yield, well....

quicksilver - 23-4-2010 at 10:06

Enclosed is the classic DuPont November 20th patent that all the fuss was made about (the law suit between DuPont & Nobel).
Herein is used the "dissolved in HNO3 and precipitate with H2SO4" model.
If you really want higher yield (a seriously higher yield) then you need to realize that scaling up or down does not always follow the multiplication of acids w/ nitrated materials path.

That being said, the collective experiments in several hobbyist notes came up with the 100/60/15 level of percentages as giving the best return for solid nitrate in sulfuric acid.
100gr H2SO4
60gr KNO3
15gr Erythritol

On a realistic basis this ratio was scaled up to 60gr Erythritol (as were the rest also scaled up, of course) & all seemed well until the 60gr limit was reached.
A question that had arisen time & again was: a discussion from several years back regarding the various solid nitrates & their effectiveness in synthesizing a mixed acid. I do recall the final observation made by several people & generally less NaNO3 was needed to do the job as KNO3 & HN4NO3 were about equal. If you have a further interest as to why; you can search for that discussion.



Attachment: ETN_du-pont.pdf (156kB)
This file has been downloaded 1131 times

[Edited on 23-4-2010 by quicksilver]

DougTheMapper - 26-4-2010 at 07:56

That .pdf is extremely interesting.

His process involves the dissolution of erythritol into sulfuric acid, then the introduction of this solution to nitric acid to nitrate the erythritol at as much as 60C!

He also claims that the majority of the heat given off occurs as the erythritol is dissolved in the sulfuric acid.

I see this as a way to achieve an excellent yield as the dissolved erythritol is essentially in the smallest physical form possible, allowing for more complete nitration as oppose to adding large "chunks" of the powder with a lower surface area.

Based on the .pdf, I propose two new ways of synthesis which both use the following materials:

5.5 parts conc. H2SO4
7 parts HNO3 equivalent of a nitrate salt
1 part Erythritol

Place the erythritol in a flask in an ice bath. Slowly add just enough sulfuric acid to completely dissolve the erythritol without exceeding 40C. In a separate flask, use the rest of the SA to dissolve the nitrate salt. Both solutions are brought to 40C and slowly mixed, maintaining above 40C but less than 60C. This is continuously agitated for 30 minutes, at which point the ETN has been formed as a liquid, eliminating the typical difficulty of stirring. (According to the .pdf, the ETN is formed as a liquid when the bath is 40-60C, but I believe the MP of ETN to be 61C, so this might require a bit more heat. I'm not sure what the presence of the acids will do.) This mixture is then chilled in an ice bath with rapid agitation to form fine ETN crystals. The acid is diluted with water, partially neutralized (as so not to destroy the filter), and the ETN is filtered from this solution. The filtrate is then neutralized, dissolved in hot acetone, and crashed into a large volume of water to achieve recrystallization.

Alternatively, large crystals can be obtained by evaporating the acetone and super fine crystals by rapid agitation while water is added to slowly to force it out of solution.

Thoughts?

-DTM

[EDIT] - I'd try it but I won't be back to the lab until the weekend.


[Edited on 26-4-2010 by DougTheMapper]

quicksilver - 26-4-2010 at 14:26

Actually Doug acetone is TOO strong a solvent for ETN.
This is why ethanol and methanol had been used w/ success and could also control the crystal size without shaving concerns or other steps. Generally speaking, the 1.51 HNO3 solution of the desired nitration and using sulfuric to precipitate it out was very common back 100 years or so. It gave more temp control. You see you can start with cold HNO3 and as you add your target product, the rise in temp is much less than mixed acids.
Some time back hobbyist experiments included making one's mixed acids (using a solid nitrate or not) damn near freezing and adding the material in very uniform, time incremented amounts. The idea was to have a greater grasp of control [not only] over "run-a-ways" but to increase efficiency in that uniformity.

Most folks know that when the nitration of solid polyols reaches a certain point, the solution almost looks like porridge & is tough to continue to mix. By using the "HNO3 solution first" route, that issue is lessened to a greater degree. The question many ask is could that be used w/ 70% tech HNO3? Often, it will work, if the sulfuric is really reduced to 98% and not drain-cleaner grade. The wonderful thing there is that cooking down H2SO4 will give good results.

maxidastier - 1-5-2010 at 02:07

@Dough: Well, it sounds interesting but:
I've read that at a certain temperature (little above 35°C) the formation of Erythritol Carbonate (or sth. like that, I don't know...) begins, which means: NO ETN!
Also, there are lots of brown NOx fumes even at 30°C and great loss of Nitric Acid.

As I see: At the beginning of the thread, everyone says: Don't let it get over 30°C...now we're at around 60°C-.- uh!

Well, I'm trying it right now, not with nitric acid, but with nitrate salt and hoping that my ammonium nitrate doesn't get dehydrated at 50°C as said someone before in the thread...
If it doesn't work out, I'll try KNO3. Hope this doesn't deyhdrate..?

Please try it out, when you're back to lab. I'm quite curious...

[Edited on 1-5-2010 by maxidastier]

maxidastier - 1-5-2010 at 02:29

@quicksilver:
100gr H2SO4
60gr KNO3
15gr Erythritol

according to other descriptions, it has to be 100 ml H2SO4, so 200g!?

maxidastier - 1-5-2010 at 04:36

it fu**ing didn't work with dissolving Erythritol in H2SO4 and then adding nitrate salt ammonium nitrate.
At 50°C it fumed so much, I think all nitric has fumed away. Seems right with dehydration of AN.
Yield is so fu**ed up.
Either I'll try now KNO3 or I will do that: Half amount of H2SO4 for dissloving Erythritol, another half for nitrate salt, but at low temperature. When nitric acid has formed, then I can try rise temperature again...

quicksilver - 1-5-2010 at 05:20

NO, when the commonality is weight; a conversion is based on density. NHO3 1.51 would be 1.5gr as expressed in one's formula. H2SO4 also depends on density level - 93% weighs less than 98% so the arithmetic starting point depends on your level of purity in liquids presented in grams: weights not volumetric milliliters.

The majority of properly expressed formula is done so in a commonality, even if the expression some use is "recipe'". Be very careful of simplistic "recipes" as they often are written by people who don't do the math first; then the lab.

[Edited on 1-5-2010 by quicksilver]

maxidastier - 1-5-2010 at 05:52

so I add 60 g of nitrate salt to 100 g of H2SO4 95%?
I tried, but it's impossible to stirr...

gnitseretni - 1-5-2010 at 15:05

Question..

After the last addition of the Erythritol, instead of letting the mixture sit to nitrate for an hour and stirring every once in a while.. could that nitration time be reduced to say HALF an hour if you stir the mixture continuously by mechanical means?

I was thinking of making a little stand and attaching a hand mixer to it. I'll make one anyway regardless of the answer, just would like to know if I need to turn it off after an hour.. or half an hour.

I actually made such a mixer before, but I took it apart a while back when I decided to quit the hobby. I sold my acids and everything!! Fuck!! People even warned me I would regret it.... I should've listened :P

maxidastier - 2-5-2010 at 01:58

nitration time is 20-30 mins, but it doesn't hurt if you make it 45 mins; stirring, at least every 5 mins, is important.

@quicksilver: Every "recipe" I tried, even from that thread here, says 100 ML to 60 g (50ml to 30g), not 100 g to 60 g!!
So all those recipes are wrong?

[Edited on 2-5-2010 by maxidastier]

quicksilver - 3-5-2010 at 05:34

One of the reasons NOT to use recipes is that it doesn't teach chemistry. The convention of using all the same units of measurements (especially weight) is so ingrained that I use it consistently -that one reason NOT to use recipes but do the math and determine if you have it right. 100ml appears correct if the density level is 1.81. But mixing weights and volumes is a poor idea unless it's noted. Recipes are not chemistry.
Standard convention aside, I made more than one mistake in notation.

maxidastier - 4-5-2010 at 07:17

I have 95% H2SO4...so do I need 100 g or 100 ml??

hissingnoise - 4-5-2010 at 07:48

You need to find a simple hobby. . .
Stamp-collecting, perhaps?



not_important - 4-5-2010 at 08:04

The reason liquids are measured by volume rather than by weight is that it is easy to pour liquids than weigh them, and more particularly once was once much more so. But to use volume you need to know the density of the liquid, so that you can calculate the mass that volume represents and from that the molecular proportions.

So, how grams of H2SO4 is there in 100 ml of 95% H2SO4? Should be easy to find a table of densities for various strengths of aqueous H2SO4.


The WiZard is In - 4-5-2010 at 09:15

Quote: Originally posted by quicksilver  
One of the reasons NOT to use recipes is that it doesn't teach chemistry. The convention of using all the same units of measurements (especially weight) is so ingrained that I use it consistently -that one reason NOT to use recipes but do the math and determine if you have it right. 100ml appears correct if the density level is 1.81. But mixing weights and volumes is a poor idea unless it's noted. Recipes are not chemistry.
Standard convention aside, I made more than one mistake in notation.



Like the old Chemistry Sets.. they weren't Chemistry Sets —
they were Chemical Sets. Chemicals yes - chemistry limited.


djh
-------
Science is a collection
of successful recipes.

Paul Valéry
French poet-essayist
(1871-1945)

maxidastier - 5-5-2010 at 03:12

@noise: maybe you just stop making noise

hissingnoise - 5-5-2010 at 04:34

If you want to play with high explosives you need to be able to think for yourself. . .


maxidastier - 5-5-2010 at 06:10

So I'll try to find out how many milliliters of 95% H2SO4 are the same as 100 g of 100% H2SO4, right? To these 100 g / X ml 95% H2SO4 I add 60g nitrate and 15 g Eryhtritol...

maxidastier - 15-5-2010 at 02:18

when the task is 100g H2SO4/60gNitrate/15gErythritol, then 100ml of 95% H2SO4 are way enough, because:
100g H2SO4 are needed and 100 ml 95% H2SO4 contain 100*1,834g/cm³*0,95= 174,23 g H2SO4.
Please correct me.
I think it doesn't hurt if you use too much of H2SO4 than too little?

quicksilver - 15-5-2010 at 10:30

Quote: Originally posted by maxidastier  
.
I think it doesn't hurt if you use too much of H2SO4 than too little?


A synthesis is not a recipe. A synthesis is generally a balanced equation of reproducible type. In chemistry, chemical synthesis is purposeful execution of chemical reactions to get a product, or several products. This happens by physical and chemical manipulations usually involving one or more reactions. In modern laboratory usage, this tends to imply that the process is reproducible, reliable, and established to work in multiple laboratories.

A chemical synthesis begins by selection of compounds that are known as reagents or reactants. Various reaction types can be applied to these to synthesize the product, or an intermediate product.

In organic chemistry the maintenance of a variable such as "this much H2SO4 / that much H2SO4" will NOT yield a reproducible result! To use "too much" or "too little" is not chemistry & will NOT yield a synthesis. It may yield a reaction; that consistently has a variable - and this teaches only that. The "yield" in that instance is at best, an accident.

Therefore; it damn well is inappropriate to not measure your reactants. You are discussing the synthesis of a high explosive. Perhaps one of the most serious agendas in lab chemistry.
To not do all the background study necessary to determine your OWN answers is to invite disaster! I wrote recently about someone who lost an eye & thumb in a synthesis of NG. I do not know whether he knew the lab techniques or chemistry necessary to prevent that tragedy; however, he might have prevented it.
I dearly hope this is the LAST of this thread. PLEASE do yourself a favor and listen, study & do your own work. You risk an extremely serious situation & out of a sense of humanity and compassion I hope you take this advice to heart.

End this thread: study the elementary synthesis process. Study the proper Lab techniques. READ books on proper lab technique & remember them.
There are very FEW accidents, in reality there is negligence. Ignorance of proper technique is negligence & just as with firearms, it is too late to say you're sorry if bad becomes worse.

You may never really realize the compassion in this response; but it may really save your butt.

maxidastier - 16-5-2010 at 05:43

Would you be so kind and tell me: What is so dangerous about adding too much H2SO4 IN THIS PARTICULAR synthesis?
Anyway, chance of a runaway or anything is very low with ETN compared to others.
Sulfuric acid is stripping away hydroxyl groups from the erythritol and the protonated hydrogen from nitric acid and absorbing the water that is produced. Concentrated sulfuric acid is acting as the limiting reagent, once it has absorbed enough water it will no longer attack the polyol. This means less chance of destroying unnitrated or partially nitrated erythritol.
I need H2SO4 for two thing: the one mentioned above, and, of course, producing nitric acid.
My question again: What is the best amount of H2SO4 (in gramms, milliliters or whatever)?

And btw: Be sure: I'm watching my ass...

Justin - 16-5-2010 at 06:40

I found that using 100mL 98% H2SO4 per 7.5g erythritol gave me back a yeild consistantly 1.8 times the amount of erythritol used. I used KNO3 fyi

maxidastier - 17-5-2010 at 10:19

And how much KNO3?

Polverone - 17-5-2010 at 17:51

Maxidastier, let me remind you of your own words earlier: "We need to try out different ways if making ETN"

It seems that you have tried many things, but I don't see the sort of systematic investigation that you need to establish patterns and investigate hypotheses. Work in small batches to conserve reagents before scaling up, vary one experimental parameter at a time, and try to repeat the conditions of a particular synthesis a few days apart so you can see how much uncontrolled variance in yield you can expect even when you're trying to do the same thing again.

Although not strictly needed to investigate changing reaction conditions, you'd also make faster progress in interpreting prior writings if you read up on stoichiometry. Nobody is born knowing it; there's no shame in needing further education. But you will ask more effective questions and learn better if you acquire this information before continuing the quest for optimized ETN synthesis.

Justin - 18-5-2010 at 10:51

^^ i agree very much, after my first few small scale ETN synths with good yeilds i jumped up to 60g erythritol, this amount however produced horrible yeilds, 50g ETN!. So basically i wasted good reagents!!! Very good advice Polverone

maxidastier - 19-5-2010 at 07:10

That's not the point. I always made it small scale. My question is only how much of every ingredient is needed.

Formatik - 19-5-2010 at 08:29

Start by writing a balanced equation for the electrophile nitronium, since this is what nitrates the sugar.

Though even with correct amounts, you shouldn't obtain a yield as good as using nitric acid since potassium nitrate and sulfuric acid form a less active nitrating system.

In the real literature, I've only seen this nitration system being used for aromatics. The only good point about it is the water of nitric acid is avoided and also less toxic fumes than from something like handling fuming nitric acid.

gregxy - 19-5-2010 at 10:48

I did this synthesis a few years ago and it seemed that the
yield problems come from problems with mixing. As more E is added the mixture becomes thicker. The ETN seem to form
clumps and I think the ETN may coat the outside of the E
granules and prevent the acid from reaching them. The
result is a lot of partially nitrated product which is water
soluable.

It seemed to help to make sure the E was very finely ground.

Other things that helped were to boil the acid to remove as
much water as possible. If the acid is 93% by weight (what
people claim for Rooto) it is only 71% acid on a molecular
basis (3 molecules of water for each 7 molecules of H2SO4)
so boiling it down to 98% is important. I assumed one
molecule of H2SO4 is needed for each molecule of HNO3
produced and for each molecule of H2O produced or present
at the start. If NaNO3 or NH4NO3 are used as the nitrate
salt they may also contain water. I tested my NH4NO3
by heating it to melting in a test tube and did not observe
any condensation at the top so it seemed to be dry.
My NH4NO3 also dissolved cleanly in water so it seemed
to be free of clay

My results:

On a Mole ratio basis: 1 C4O4H10 : 6 NH4NO3 : 11 H2SO4

20g H2SO4 (Rooto)
Boiled off 2.6 grams of it
Added 8g NH4NO3
Added 2g C4O4H10 (slowly at 0C)
Then let it stand for 1hr,
drowned in 100ml of ice water.
Needed to filter, the crystals would not settle out.
Got 2.6g product = 52% still not great.

domstp - 24-5-2010 at 07:46

what are the effects of excess water in the reaction mixture? why would the yield be less using 30% concentration sulphuric acid and 3 times the nitration time.

hissingnoise - 24-5-2010 at 08:24

Water interferes with the nitration reaction (A-C hydrolysis) and 98% sulphuric acid in nitration mixtures binds up H2O to minimise this hydrolysis of the formed product.
No yield of nitrated product is possible using 30% H2SO4 for any length of time.
The water it contains *must* be boiled off before it can be used for nitration. . .


domstp - 24-5-2010 at 08:35

thanks, that was what i was looking for.

quicksilver - 25-5-2010 at 05:51

hissingnoise 's response is possibly the most important however there is another significant issue. Often "sub-nitration" are produced such as "di & tri nitrates" and these may be soluble in water and lost to the final yield. They may play a role in that, they may be productive energetic materials if utilized WITH the final appropriate nitrated product. This is significant in nitric esters especially the solid alcohols.
Small yields of mannitol are the most obvious of these. Their occurrence in PETN has been documented by several chemists as well. Since Erythritol is very fast nitration, the possibility of various byproducts as sub-nitrations is very possible. Normally these would co-exist but with excess water it's possible they'd be washed away.
This is one of the reasons why scaling up is not always a case of multiplication of materials. What may be fine with 5gr of solid alcohol may have a lesser yield with a value of 30gr.

gnitseretni - 25-5-2010 at 06:04

Is a fast addition time a way to reduce sub-nitrations?

I've read posts where folks use long addition times. If after the last addition they let it react for 15 minutes, then the first addition has had a reaction time of one hour and 15 minutes, and the last addition only a mere 15 minutes. Is this large difference in reaction time a cause of sub-nitration?

quicksilver - 25-5-2010 at 11:55

Quote: Originally posted by gnitseretni  
Is a fast addition time a way to reduce sub-nitrations?

I've read posts where folks use long addition times. If after the last addition they let it react for 15 minutes, then the first addition has had a reaction time of one hour and 15 minutes, and the last addition only a mere 15 minutes. Is this large difference in reaction time a cause of sub-nitration?



It is very difficult to say that one specific method would result in a lack of sub-nitration because each nitration is a somewhat unique reaction. Great effort goes into making a nitric ester consistent on a plant-level.
For many purposes they are not a negative bi-product....but for a situation that demands consistency such as smokeless powder they certainly are. To answer the question (TTBoMK) it's a CONSISTENT addition (or rather exposure) that would make a difference. Say you find that adding your solid alcohol to a mixed acid milieu in weight of .25 gram every 3 minutes is appropriate to maintain reaction (or deflect run-a-way). If then you actually set a timer (wrist watch) to your additions, you may have the best chance to maintain a single-level nitration (see: Federoff).

gnitseretni - 27-5-2010 at 08:48

Made some ETN.





10g Erythritol
50g KNO3
150ml H2SO4

Yeah, I know.. that's a LARGE excess H2SO4 ;)
I recrystalized the ETN from acetone/methanol (50/50).
Anyways, I know it's nothing special.. I was just a little bored and felt like sharing :P

Justin - 27-5-2010 at 14:45

What was your final yeild?? i like the electric mixer idea!! may have to try that, however im a bit concerned about the acids corroding the metal mixers, my wife would be sooooo PISSED!!! LMAO

gnitseretni - 27-5-2010 at 16:17

Yield was kinda bad.. only 11 grams. I thought for sure I would have more than that when I drowned the mixture and saw a thick layer form at the bottom. Although it did look a little... fluffy. I left the mixer on for 20 minutes after the last addition. I'll make it 30 next time.

The mixers start rusting after just two uses. I just sand the rust off and reuse them.

seppe - 28-5-2010 at 08:23

hey i m new on this forum ... i need littel help ... etn how much dissolves in 61 degrees hot ethanol thx boys

Jimbo Jones - 28-5-2010 at 10:57

Based on my tests, the nitration of ETN is the easiest of all nitric esters (except EGDN I guess). Yields are excellent, even with the nitrate & acid combo. The biggest problem with the solid sugars is there slow rate of solubility. The electric mixer is not a bad idea, but manual stirring in every five minutes or so will give you the same results. 100 ml. 95 % sulfuric acid, 75 gr. AN (recrystallized) and 15 gr. E gave me around 21 – 22 gr. pure, recrystallized from methanol ETN. For maximum yields the E have to be ground to very fine powder, which speeds the nitration considerably. Add in little portions with good stirring to prevent the clumping. Some people left the mixture from 20 to 30 minutes after the last addition, but around 1 hour is good if you want to achieve maximum yields. The recrystallization from alcohol is also very simple. For every 10 gr. ETN I use around 100 ml. hot methanol (forget the acetone). The temperature must be below 60 °C, because of the ETN low melting point. Stir the crystals until everything dissolve, then test with litmus paper and add little portions sodium carbonate if this is necessary. The hot solution is filtered directly in container with ice cold water and 1 % urea. I use magnetic stirrer for the water, but manual stirring is also ok.

seppe - 28-5-2010 at 11:56

Thanks for your help .... But the information I need for ethanol ... is the solubility of methanol almost like ethanol

Jimbo Jones - 28-5-2010 at 12:04

Yes, but I prefer methanol. Pure.

gnitseretni - 28-5-2010 at 12:31

I've used the mixer for a long time, but I only used it with HNO3/H2SO4 mixtures. I just recently started using it with KNO3/H2SO4 mixtures. I used a large excess of H2SO4 in my last synth a few posts up, but the first time I did it I used the right amount of H2SO4 and found that the mixture was too thick... eventually the mixture became so viscous that the container itself began to turn instead of the mixture :P So if you're gonna use a mixer then either use an excess of H2SO4 or find a way to secure the container to keep it from turning. But best to use it with HNO3/H2SO4 mixtures in my opinion.

I like using the mixer because I have my hands free to do other stuff, like in between additions I can back away to avoid those nasty HNO3 fumes.

Btw, the electric mixer is best used with larger synths. With smaller synths you use smaller containers, obviously, which might create problems. For example, I used a canning jar in my last synth. The mouth of the jar was very narrow and some of the material to be nitrated hit the top of the metal mixer and flew against the walls of the jar, which I had to scrape off from time to time. I didn't have this problem with larger synths, because the mixture completely covered the metal mixer. This problem can be overcome by cutting the four 'blades' on the metal mixer in half.. leave the bottom half of the blades attached to the mixer but remove the top half so there's nothing there that will hit the material to be nitrated against the walls of the container. If I didn't explain that well enough, see picture below.


JohnWW - 28-5-2010 at 13:05

That mixer looks like an egg-beater! But, in view of its being used to agitate HNO3-H2SO4 nitration mixtures, what metal are the shaft and blades made of? Or are they fully coated with some acid and heat resistant non-metallic material like PTFE?

gnitseretni - 28-5-2010 at 13:35

Yeah egg-beater.. hand-mixers whatever you wanna call em. They're only 7 bucks or so at the Walmart. As for the material.. not sure, probably some shitty quality SS. They start rusting after just one or two uses. But just sand the rust off and/or dip them in HCl and they're good to go again.

seppe - 30-5-2010 at 08:46

is re-crystalization etn more sensitive to friction and impact than not re-crystalizion etn ?

hissingnoise - 30-5-2010 at 09:23

Crude, non-recrystallised explosives are usually more sensitive because their purity is questionable.
Recrystallisation of these compounds is always recommended. . .


maxidastier - 16-6-2010 at 09:49

....if you don't use it immediately or dissolve it in NG or whatever. ;)

pjig - 16-6-2010 at 22:18

As far as ETN goes,,, is there a way to indefinitely store it ? I'd assume that in a aqueous solution of alcohol or maybe h2o would work. I know this is how they store picric acid( in 10-30% h2o). Would it store in a solvent like nitromethane for a long period of time (few years)?

Rain - 17-6-2010 at 04:41

I think acetone would be a good choice in this regard, as you know the ETN won't come out of solution.
By adding an excess of sodium/calcium bicarbonate with urea to fight off any acidity would be advantageous.

The bicarbonates would dissolve in the water, along with other impurities when recrystallizing your ETN.
Then just follow the 50/50 ethanol/acetone route to get finer crystals.

hissingnoise - 17-6-2010 at 05:53

If ETN is well neutralised and recrystallised a few times it should be pure enough for indefinite storage in a fridge. . .


maxidastier - 3-7-2010 at 09:57

Can someone help me with the equotation?
I'd like to use my distilled 98% HNO3 instead of KNO3..

What amounts are needed for 10 g Erythritol?

Can someone suggest me a chemistry calculator? I read about the gnome chem calculatur, but I don't have ubuntu.

quicksilver - 4-7-2010 at 11:00

If you really want one of the best suites then I'd suggest ChemOffice because then you could calculate, illustrate, & have a great deal of fun.
http://www.cambridgesoft.com/software/ChemOffice/

That and a strong undergrad textbook like ISBN 0-534-17035-8 (look that up on Amazon, they have used copies from about 30 large universities.)

[Edited on 4-7-2010 by quicksilver]

maxidastier - 9-7-2010 at 09:46

Well, thank you, but as I see, this programm as a little bit overseized.
I really just need a equotation programm, that knows molar mass and those things to calculate how many grams/mls are needed nitrate 10 g of ETN etc...

sdodgen62 - 13-1-2012 at 18:45

help,
i cannot understand why my nitrations are going ary, with the proven 1;4;12 ratios and the nitrification appearing to go well, not very thick until it nitrates for an hour or so. beautiful crystals needle like come out of the freezer. but i can't know what i have here.... no bang

sdodgen62 - 14-1-2012 at 06:31

maybe it has something to do with using a denatured alcohol instead of ethanol hmmmm
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