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XeonTheMGPony
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[*] posted on 4-2-2016 at 18:07


Well I ordered 1pound of Erythritole at 99.95% purity from a hippy shop here in town, cost 12dollars cad! to give an idea of how insanely good that is 270g of truvia costs 10 dollars cad here and it is contaminated with stevia!

So now with clean pure erythritol, higher concentrated acid, batch 7 had insane crude yield.

Comments:

For any one ells having issues,
#1 it is very highly advised to either recrystallize your erythritol or buy pure erythritol.
#2 Using well concentrated sulfuric acid pays off well! It is worth the hassle.
#3 Keeping it at 10c during the addition time and for the remainder of the reaction then warm to 20c for the last 10 minutes, seems to ensure full nitration. 1H is all it took from start to finish.
#4 Good stirring goes a long way.
#5 Grind your erythritol and sieve! ensures steady fast reaction!

I now have a successful good yielding batch with these protocols and following the 4 nitrate to one erythritol rule.

this is the last time I'll spam this thread unless a question is asked!
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[*] posted on 4-2-2016 at 21:05
Why oh why?


I've been reading this thread over and over again since I wanted to try ETN a long time ago.

I will make a shitlong post about my own expériences but here are the few recurring points I see almost everytime and I dont get why you guys do this:

- You know nitration will go slower a lower temps. You know you shouldnt exceed 20 to 25 C°.
The nitration being done almost immediately after you dump the erythritol (provided we're still at the beginnning of the nitration and there's not too much water in your mix) why would you keep it going for more than 1 hour? Safety by letting the temperature go up and make sure your product is properly nitrated? Ok, I get it, though I think its wrong. But then the very few times I did this I noticed some NoX after about 30mn after the and of the addition and obviously the yield was lower. And yeah, I'm good at temperature management. So good I wondered a couple of times if I wasnt missreading the temps. Add some ice cold HNO3 at the end rather than waiting. This part I still have to try but I bet yields will be better and you WILL nitrate all these mono and di nitrates that go into solution otherwise.
Please note that I do realize that most of you use salts. What's the problem? Prepare some more ML with H2SO4 in the freezer beforehand.

- Why oh why crash your ETN in so little water?!! I've seen synths here that were obviously getting low yields because at the speed the ETN was poured in ice cold water the exotherm from the acid would destroy the product!
ETN is insoluble in water ! It's mono and di-nitrates are not! Get rid of them right away! Even for a simple 20 grams nitration I have a 2 litres beaker sitting in a 5 litres bucket filled with ice chips. You dont care how much water you'll use to dilute the acid unless you're in a hurry to filter. The first time I did that I used and abused Ice cubes so much I would have bet I even managed to crystallize the mono and di nitrates at the bottom of the beakers. It's very stressfull to try to dislodge a piece of this material with a glass rod and try to understand what it is. I'm still not sure yet as most of the time, when this happened I didnt want to have potentially dangerous EM's at the bottom of beakers that needed cleaning. So I doused the whole thing in acetone, made a torch, set it on fire. Goodbye hazardous whatever. I'll analyze you some other day. Anyway, the ETN was happily floating in the upper layers of the water.

- Coffee filters !!!
Do the same synth with proper filters and see your yields go up. You'll be amazed! Sure, coffee filters filter out much more quickly. That might be because they have much larger pores! Keep the filtrate in the fridge for one night and tell me I'm wrong!

- Recrystallization:
Why would you dry your ETN BEFORE recrystallization? Sure, neutralize it with whatever you feel is convenient (I'm not convinced on the ammonia thing but that's precisely why I'll be giving it a try someday). Neutralize with a bicarb solution as much as you need, press the filter paper(gloves on! and be careful not to crack the filter paper otherwise it'll complicate things). I've taken the filter paper several times directly after filtration, made a "ball" and squeezed it a few times in bicarb when I was in a hurry. But that's the beauty of things: you're not wasting time by drying the ETN so who cares: it is still taking less time.
And now that you have your ball of ETN soaked with water (at least as possible), next to no acid, a bit of bicarbonate left around, why dont you put it straight into your 55c° methanol? Maybe even add a few pinches of your prefered water/methanol soluble stabilizer?
It's both time efficient and a sure way to get rid of all the extra acid still trapped in the crystals.

I've read somehere around here (SM I mean, there to much knowledge in this forum to remember exactly where after lurking for several years) that one stabilizer might not be replaced by another for a similar synthesis (Rosco has a way a saying things in just one sentence that I would need 3 paragraphs just in the hope to get myself understood).

I'd love to hear more about your stabilizers, why you think they are better than others (sodium bicard, urea, diphenilamine or others).

I sometimes recrystallize ETN two times:
- One for the acid
- One for the shape of the crystals (and extra #1 reason).
This ETN I use for making detonators. I'm still perfecting the process.

Considering how long this post was (I meant to keep it short, I'm very sorry). I guess I'll just go from page 1 to 6 to criticize, ask questions about what you have all written here. I'm sure as hell I'm not an expert on this EM (or any other) but some of you have made comments that made me jump while others just made me Wonder why dont we all share this common sense.
I'm a noob compared to some of you but yet you say things that I consider shocking. I hope my straightforward speech will not make you think I'm looking for argument, fight, trolling or whatever. Its just that English as you must have guessed by now is not my mother tongue and that we are talking about things that may affect your lives forever.
Gosh, I hope I'm not too boring to read ;)
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XeonTheMGPony
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[*] posted on 5-2-2016 at 09:42


Time/temp = Deff needed when dealing with the salts/acid mix, after testing out a few comboes this provides best yields. with the higher concentrate of acid and the pure erythritol I could have terminated at the 30m mark with good yield, but I wanted to squeeze every bit out

If one is using concentrated Nitric acid I would not recommend ever elevating the temp, and terminate the second the temps start to fall to ice bath levels.

(You know the main part is don as temps start to crash to ice bath levels, I raise it via warm water bath with no added heat to ensure full through nitration. Never use hot water for this step, I use just 150ml of warm water in a bath for it.)

Crash water: My personal method is to leave it in the freezer till there is a solid ice layer on top and bottom and I use 2x of my nitration volume, for the washing how ever I use as much as required till no acid remains in either the filter paper or material.

Coffe filters = Negligible losses, I am the type that settles the wash water for a day or so to watch for just such occurrences and to ensure nothing makes it out to the environment that may be harmful.

reason I dry it was to track the befor / after weights to infer on my nitration efficiency. (Now that I have a solid handle on it I'll be dropping this habit)

All so the lesser water improves on the required alcohol volumes for the recrystallization, but soon I'll be getting gear to recover/recycle the alcohol.

Those are my answers to the questions put fourth.





[Edited on 5-2-2016 by XeonTheMGPony]
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[*] posted on 5-2-2016 at 13:33


I have successfully made ETN with a mixed nitrate approach,

25ml H2SO4
10ml 60% HNO3
8g KNO3
4.5g Erythritol

x15 batch size.

Start cold, let warm to room temperature for an hour.
Standard recrystallization.

Result: Good ETN with 40% yield.


There are many formulas out there on making ETN.

I grabbed a couple of formulas that have been tried by other members on this forum, reporting good yields, and proceeded to calculate the initial pH, [NO3], [NO3]/[Erythritol], [H2O]
[..] = concentration of ..

With these values I built my own synthesis while allowing for 60% nitric acid to be present.
I added this nitric acid to reduce the thickness of the mixture, helping it to be stirred by a PWM motor.

It worked, the solution was not so thick as many members report when using KNO3, and was easily stirred.

I did not however grind the Erythritol before adding it in. It was in sugar sized grains when I added it.

It would be great if someone could report back on the effects of not grinding the Erythritol before adding it in the nitrate mix vs. adding it in fine powder form.

Does the Erythritol simply dissolve in the nitrate mix, or does an ETN layer form around each grain, preventing further nitration of the inner layers of that grain? Aka: an Erythritol grain being passivated by the ETN forming around it.

If the second case is true, I can imagine an improve in yield by fully dissolving the Erythritol in the sulfuric acid, then cooling it, and only then adding the nitrate salt or acid.

Only a theory of course.
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XeonTheMGPony
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[*] posted on 5-2-2016 at 17:03


grinding it first provides a vastly improved reaction I have found, adding it as is lends to poor yields and long reaction times. I played around with allot of variables.

Best yield and reaction time = 4nitrate to 1 erythritol, grind and sieve then add to mixed acids.

I average 17 in and 20 to 21 out after recrystallization!
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[*] posted on 7-2-2016 at 00:46


Dissolving pentaerythritol before nitration process in cold HNO3 is possible. This method Give a high yield. However if you use same methode for erythritol, yield is almost pure zero. For classic methode is important perfect dry erythritol in fine powder consistency. And quickly diffuse in nitration liquid. And it is usually also difficult. Dissolving E in H2SO4 before process no tried. When is E only minimal wet, yields are lower. Estimated 70% against total dry E. My experience during 10 process. Doc.
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[*] posted on 7-2-2016 at 13:45


By far the best yield I have knowledge of was reported by this synthesis, on another topic, by Microtek:

Quote: Originally posted by Microtek  
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. (...)


Other members reported scaling this 20x with success.

Notice the "very fine powder" condition. Also, the very low temperature.

I don't have a ball mill, only an electric coffee grinder.
How long will it be enough to grind my erythritol?
1, 5, 15min?

I'm away from my lab so I can't test anything atm.

I tried dissolving erythritol in room temperature 60% HNO3, but only to find I couldn't dissolve enough for the full synthesis.
I don't remember testing with H2SO4 however...

Also, what are your opinions on using KNO3 vs NH4NO3 as a nitrate salt for these reactions?
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[*] posted on 8-2-2016 at 01:38


Using ammonium nitrate is preferable for a more fluid reaction mixture and ease of stirring. With potassium nitrate broken glass rods are common if you don't add extra sulfuric to thin it some. And there's no set time to mill your erythritol. Just powder is fine. A couple of mins in a mortar is what I do. It really doesn't matter since you generally nitrate it for at least 30 mins after the last addition and at around the 20/25c mark you should get a pretty fully nitrated product in a normal sized batch of 10-20g. It's been a while since I've done ETN I ditched it in favour of PETN but it is still very powerful and its ease of preparation and finding precursors make it a popular choice as ever for hobbyists. It was the first solid ester I made and I was in awe of the damage a small amount did for such a benign Looking substance.



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[*] posted on 16-8-2016 at 09:29


Hello I distilled off pure nitric acid and did the synth, just recrystallizing now but could some one look over my math and tell me if I was out to lunch?

The yield looked good and my goat the purity is mind blowing compared tot he mixed salt method! beautiful snow white crystals, next to no sludge during recrystallizing, just miles ahead of the nitrate salt / acid approach.


I'd like to thank a you tube tutorial for finally making it all click, he explained stoichometry in such a way that made every thing fall in place so I been using it for every thing to get used to it. I found finding the products difficult so need more practice on that end.

math.jpg - 121kB
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[*] posted on 16-8-2016 at 09:32


The product of said math and following synth

pure acid product.jpg - 127kB
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[*] posted on 18-8-2016 at 05:02


Yeah, looks right, although you typically use an excess of nitric acid to make sure that the reaction goes to completion. How much of an excess is up to you. Also, I pretty much always use Wolfram Alpha to calculate molarity anymore, since it just makes things a lot easier and less error-prone. Once you know how to do it by hand, it's not cheating to use a calculator. :)
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XeonTheMGPony
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[*] posted on 18-8-2016 at 08:38


I did use an excess by rounding up the numbers, I skimped on time though I didn't leave it sit long enough so ended up with dismal results, but that's what happens when you rush.

thanks for looking it over.
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[*] posted on 10-10-2016 at 12:46
What about 65% HNO3 ?


I've read this topic and lots of other ones on the forum about ETN synthesis.
It seems that the most popular source of NO3 anions is KNO3 but I've also read that using higly concentrated HNO3 would give better results. What if one uses a weaker HNO3 concentration, like only 60% to 65%? Only the yield would be compromised or even other ETN parameters such as VoD, sensitivity, stability etc?

[Edited on 10-10-2016 by Tricka90]
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[*] posted on 11-10-2016 at 00:16


I use 70% nitric with 98% sulfuric to make PETN and NG before so 65% should work with ETN too.
There are some explosives that require high concentration 99% nitric such as RDX and HMX etc.
Too weak nitric acid would probably just not attach the 4 nitro groups to all the product and maybe lower yield would be my guess.
I would add an excess of sulphuric instead of lower concentration nitric as more dilute HNO3 would mean more water in the reaction and less sulphuric to take it away. Whereas, if there is an excess of 98% sulphuric, it should be able to pull the extra water from the dilute HNO3 and H20 byproduct from the reaction through the whole nitration.




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Tricka90
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[*] posted on 11-10-2016 at 03:05


Thank you for the reply I will definitely follow your advise.
I was considering using the following reagent quantities:

4ml 65% HNO3
6ml 96% H2SO4
1g Erythritol

but now I'm going to add 1 or 2 ml H2SO4 more to achieve a good excess.

Talking about storage, do you think is possible to use denatured 90° etilic alcohol (the one you find in any pharmacy or hardware shop) to recristalize ETN? I'm asking because I've read that using this type of alcohol would be even better than using laboratory grade ones because it contains some anti acidic compounds which would be beneficial to ETN storage stability.

[Edited on 11-10-2016 by Tricka90]
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[*] posted on 11-10-2016 at 04:09


I make PETN with 25ml 98% H2SO4 and 35ml 70% HNO3 per 10g pentaerythritol and it comes out fine.
The ratios you listed first should work fime with 65% nitric but the extra sulphuric could improve yield and make sure all 4 nitro groups are attached.
I do a 30 min heating step at 45 degrees C in a hot water bath before crashing into ice water to crystallize to improve yield with PETN.

Do you mean ethyl alcohol (ethanol) to recrystallize?




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[*] posted on 11-10-2016 at 05:25


That's great, thank you for the informations.
Yes I mean ethyl alcohol, I misspelled it, I'm sorry, do you think it is really better than laboratory grade ethanol?

[Edited on 11-10-2016 by Tricka90]
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[*] posted on 11-10-2016 at 06:55


The hardware grade ethanol (methylated spirits its called here) is 95% ethanol with methanol which will also work for recrystallizing ETN and a chemical to make it taste bitter if people try to use it as vodka mix;)
It should still work though as I habe heard acetone is too strong a solvent for this explosive.
I have absolute 99% ethanol for recrystallizing but it is hard to aqcuire as it can be drunk as alcohol.




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[*] posted on 11-10-2016 at 08:31


That's great, thank you again.
Since I've never read about other forum members trying ETN synthesis using weak nitric acid I'm going to try it myself.
Then I'm going to share the results (yield, colour, sensitivity tests with hammer and by friction etc.) hoping to be useful to anyone who wants to try.
All the process will be carried out with temperature always below 5°C and with constant slow stirring. I'm going to prepare the two acid mixture, then slowly add erythritol. Finally I'm going to let the solution stay for 30 minutes and then pour it in ice cold water, filter the precipitate (ETN) and wash it with a sodium bicarbonate solution and then copious water.
At least that's the synthesis I've found online, hope it is correct. Maybe in my case, since I'm using weak nitric acid, would be preferable to let the solution sit at 5°C for 1 hour or more, rather than only 30 minutes.

[Edited on 11-10-2016 by Tricka90]
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[*] posted on 11-10-2016 at 11:03


Quote:
At least that's the synthesis I've found online, hope it is correct.

In nitration of organics, every effort must be made to minimise water content of HNO3 so that maximum yield and degree of nitration is obtained, cleanly.

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[*] posted on 11-10-2016 at 11:24


Recommend use perfect dry erythritol. Very fine powder, of course. But my experience is, if is erythritol dry are yields better. Much better. With H2SO4 96% + HNO3 65%. Dr.



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[*] posted on 11-10-2016 at 13:09


Thank you for the advices.

@hissingnoise:
For now I only have 65% HNO3 available unfortunately and since I'm a beginner I can accept obtaining lower yields in ETN synthesis more than having to produce highly concentrated nitric acid (via KNO3 and H2SO4 reaction) and dealing with it. Furthermore, except getting a lower yield there won't be any other bad result in using weak nitric acid, as all the properties of ETN wouldn't be undermined as far as I understood.

@Laboratory of Liptakov:
I would definitely grind erythritol and then dry it as good as I can.
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[*] posted on 11-10-2016 at 14:29


Nitric acid is not even necessary, most people just use a nitrate salt like NH4NO3 or NaNO3.

How could the properties be undermined? ETN is a molecule and will behave the same regardless of the conditions it's formed under. The lower nitrates are very soluble in water while the tetranitrate is very insoluble so a wash and simple recrystallization will yeild almost 100% pure ETN.
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[*] posted on 11-10-2016 at 17:06


Quote: Originally posted by Tricka90  
That's great, thank you again.
Since I've never read about other forum members trying ETN synthesis using weak nitric acid I'm going to try it myself.
Then I'm going to share the results (yield, colour, sensitivity tests with hammer and by friction etc.) hoping to be useful to anyone who wants to try.
All the process will be carried out with temperature always below 5°C and with constant slow stirring. I'm going to prepare the two acid mixture, then slowly add erythritol. Finally I'm going to let the solution stay for 30 minutes and then pour it in ice cold water, filter the precipitate (ETN) and wash it with a sodium bicarbonate solution and then copious water.
At least that's the synthesis I've found online, hope it is correct. Maybe in my case, since I'm using weak nitric acid, would be preferable to let the solution sit at 5°C for 1 hour or more, rather than only 30 minutes.

[Edited on 11-10-2016 by Tricka90][/


The 5 c temperature is too low.the reaction will take longer at very cold temperatures. Try keeping it at around 20-25c for best results. One hour after the last erythritol addition should be plenty of time for a smallish batch(10g)




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[*] posted on 11-10-2016 at 21:42


@OneEyedPyro: Thanks for the explanation. Obtaining a pure product in ETN synthesis seems relatively easy afterall. In the past I studied SADS, and learning how to get it to a good purity took me a lot of time.

@NeonPulse: Thank you, I'll follow your advice. Could you please be more precise about when I should let the temperature raise to 20-25 °C? Maybe I should carry out the first part of the process (acid mixing and erythritol slow addition) at 5 °C and then let the temperature slowly raise to 20-25 °C right after erythritol addition is complete, then let the solution stand for about 1 hour at that temperature?

[Edited on 12-10-2016 by Tricka90]
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