Sciencemadness Discussion Board - ETN synthesis problem

ETN synthesis problem

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Hennig Brand - 27-7-2014 at 11:58

Thought I'd post a few pictures of the over head stirring device I made for those thicker nitration mixtures. The nitration in the pictures was a 50g erythritol nitration using ammonium nitrate and 91% sulfuric acid. The stirrer was made in minutes, but I had been thinking about how to do it off and on for a long time. A second hand cordless screwdriver was used which was purchased from a thrift shop for $2. The battery was missing, but would not have been of much use anyway. An old computer power supply was used to supply the ca. 3V and high current needed to power the screw driver. A piece of 10mm Teflon rod about a foot long (IIRC) was used as the shaft. A slice from a Teflon runner found at a scrap yard was used as the paddle. The rod was drilled and threaded. The paddle was also threaded with the same thread and then the two were screwed together. Running the stirrer clock-wise causes the threaded connection to tighten not loosen in use. The little screwdriver can provide a lot of torque, given the powerful dc motor and gear head assembly. The Teflon shaft was connected to the screwdriver using a slightly undersized piece of stiff polyethylene tubing used as a coupling. The tubing was made very soft by placing it in boiling water and then forced on the screwdriver shaft and Teflon rod. During the nitration, after adding all the erythritol the stirring was continued for over an hour before dilution of the nitration mixture. The stirrer got only slightly warm after this use, even though it was a hot summer day (>25C).

A much larger stirrer could be made. Cordless drills could also be used. They are usually much more powerful than cordless screwdrivers and can often be obtained very cheaply or for free.

BTW, the process was made much smoother and much more enjoyable by using the overhead stirrer. Yield was about 1.45g of recrystallized from methanol ETN per gram of erythritol.

Post Reaction Water Dilution.jpg - 449kB

I notice that I didn't have the stirrer and reaction vessel directly in line with each other, but the set-up still seemed to work ok.

[Edited on 28-7-2014 by Hennig Brand]

roXefeller - 20-8-2014 at 16:19

How the ___ do you come across random bits of teflon junk for repurpose?

Hennig Brand - 21-8-2014 at 05:45

Teflon is used for a lot of things commercially and industrially. Just a few miles down the road from where I grew up is a scrap yard that up until 5-10 years ago, when there were several booming mills in the area, had a lot of surplus industrial equipment and building materials. The scrap yard got many of the contracts for the mills' junk, when there was demolition, modifications, rebuilds, expansions, upgrades, etc to the mills. To make a long story short, there was a lot of old industrial equipment and bits of random material lying around. I also order Teflon round stock from time to time, which is very expensive compared to what it costs for the stuff I find in the scrap yard. For example the one foot length of round stock used for the shaft above cost me about $15-20, while the paddle/stirring bar was cut from a 4-5 foot long piece of used Teflon runner that I picked up for $5. I still find materials at the scrap yard, but not as much as before when there was more industrial and commercial activity in the area. Teflon is more rarely found than other plastics, but there are always a few pieces around.

I was going to try a piece of 304 or 316 stainless steel as the stirrer shaft, but never got around to it. It would be strong, straight and it should be quite resistant to the mixed acids (I think), as well as being more easily found as scrap and cheaper than Teflon. The stainless steel mixer attachment, posted about above, most likely was made of a lower grade stainless (not 300 series). Stainless steel welding rods come in a wide variety of compositions so that might be a good source depending on what rod dimensions were available. The flux can be simply knocked off and the rod sanded a little to remove the last bit for the rods that come coated in flux. A lot of Teflon paddles could be cut from a relatively small piece of Teflon sheeting.

[Edited on 21-8-2014 by Hennig Brand]

NeonPulse - 24-8-2014 at 16:42

I have a similar unit made from an old electric motor with a PWM unit attached this way the speed can be adjusted to suit the mixtures viscosity. The only problem is there is not enough torque to keep it moving when the mixture really thickens up. Maybe I could use a screwdriver setup like this and eliminate that problem. This is a good idea. I also use a clamp attached to an adjustable arm to hold the thermometer in place as to not have it in the way. The only problems I can see with this setup is how I would be able to quickly get the beaker into a Quenching bucket should a runaway occur? Its not exactly quick to release the toggles on both arms holding the stirring unit and thermometer in place and a runaway would likely be in full swing fuming sputtering and hissing as well as showering the area with acids. Im curious to know if that were to happenHow would you deal with that event? Maybe ill keep it near an edge with a bucket below and push it in with a stick.....

Hennig Brand - 24-8-2014 at 20:15

I guess I would switch off the power to the stirring motor then pick up the lab stand and all, which would pull the stirrer paddle and rod up out of the reaction vessel. The reaction mixture could easily be drowned in water then. Just make sure the lab stand is heavy or weighted enough to hold the stirrer steady even when stirring viscous mixtures, but not so heavy (or anchored) that it can't be moved easily and quickly if need be. Of course keeping enough cold water close by to drown the reaction mixture is a must and goes without saying. You are right; it is good to think of these things before they happen. Luckily I have never had a runaway with ETN, but that doesn't mean that it will never happen.

The cordless screwdrivers have fairly good torque and the speed could be varied with PWM or even just voltage variation probably. The stirring speed of the cordless screwdriver is not really all that fast, but it seemed to work pretty well anyway (with a big enough paddle). A cordless drill would, however, have even more torque and give you a greater range of stirring speeds.

The Teflon rod I am using for the stirrer shaft has a slight curve to it. The stirrer still works fine, but I imagine it will increase wear and tear on the gear head of the cordless screwdriver or drill. Actual laboratory Teflon stirring shafts are normally Teflon coated steel, not pure Teflon from what I understand and are very straight. I was thinking of using an external bearing positioned just below the cordless screwdriver or drill which could take the abuse. The bearing in place would mean that the driver motor and gear head would see much less undesirable/damaging movements, only nearly perfect rotation. Maybe it isn't worth the trouble, since second hand cordless tools can often be found so cheap anyway. It may not be much of an issue anyway except for slightly greater long term wear and tear.

Just had a thought, if you wanted the stirrer stand/lab stand to be really secure, yet easy to move when needed, a wooden box/receptacle could be made and anchored to the bench. The base of the lab stand could sit in the anchored box (assuming a square or rectangular lab stand base). It should be a snug fit. It would hold the lab stand very securely, preventing any kind of sideways motion, but would still allow the stand to be lifted straight up if the stirrer assembly had to be removed quickly. A receptacle for the stand base could be made circular, or in other shapes if need be, but that would be a little more difficult than a box.

[Edited on 25-8-2014 by Hennig Brand]

goldenoranges - 8-9-2014 at 15:05

It is weird, I never get my mixture to get thick, and this is my personal recipe on making it;

Code:


Needed: 
2 glass beakers ~100ML
Bath container
Sulfuric Acid 98%
70% Nitric Acid
Erythritol
Water
Bicarbonate
Filters
Filter Holder
Ice, Salt, Bath

NO HIGHER 30f, Keep around 20f

Salt   - Ice Bath 
12ml 70% Nitric Acid Added Carefully
18ml 98% Sulfuric Acid Added Carefullly
30f Not to be Passed
Bit By Bit, Add Sulfuric and Nitric together
When done and cooled down
3g Erythritol, while stirring, small portions
temp around 20f
Stir 30 MINUTES 
Crash Contents into Cold water, rinse beaker
filter precipitation after it is done 10minutes should be good
make bicarbonate solution, pour on top of filter onto crystals neutralize it
rinse with water again and again get rid of bicarbonate
let dry

I follow that exactly, it gets me a pretty darn good yield, but it never gets thick? It gets thicker than it was when I first added everything, I have heard of people breaking glass stirring rods while making it though, and it is about the same consistency as 20w motor oil. Does anybody know why this might be? I am at a high altitude, that is the only reason I can think of since I am following a pretty standard method for making ETN.

[Edited on 8-9-2014 by goldenoranges]

roXefeller - 8-9-2014 at 16:18

My first thought is you are using 70% nitric acid. Are you comparing it to posts that use sulfuric and alkali nitrate? The extra salt from the in situ nitric acid reaction would cause a thicker mix.

goldenoranges - 8-9-2014 at 19:46

Hmm that must be the reason why. I never saw what they were using exactly, all I read was that it was a thick mixture. I didn't question it that much. Oh well, it is better it isn't thick, it would make it more of a hassle to stir, and I wouldn't be able to use my magnetic stirrer haha.

NeonPulse - 8-9-2014 at 20:37

I used to use 95%+ nitric acid for my synthesis so there's less liquid in the mix as well as doing 30g batches. Trust me, when the temp is around the 20℃ mark and the reaction is nearing completion the mixture is chock full of ETN and it can be pretty thick. It is even thicker if you use the potassium nitrate method. Its nearly impossible to stir efficiently making cooling a problem too.

Metacelsus - 9-9-2014 at 06:45

Yes, thick mixtures are prone to runaways (from my experience). That's why I use nitric acid instead of a nitrate salt and extra sulfuric acid.

Erythritol - Intentional Mislabelling

Hawkguy - 12-1-2015 at 20:39

I have a bit of a pyro side, so I bought a small amount of Erythritol online, from a large brand name seller. I was only planning on making a gram or so of ETN, nothing big, so I viewed the whole thing as chill. Advertised as pure Erythritol, I realised it wasn't at all. I managed to identify it later as a pure sugar alcohol, but the while thing has left me feeling a bit stiffed. Anyone knows what kinda loophole these guys must have found, and how I can sorta avoid/ see/ detect/ whatever it in the future for my transactions?

BTW the sugar smells like fruit and candy corn. If anyone knows exactly what it is, that'd be great too.

[Edited on 13-1-2015 by Hawkguy]

Bert - 13-1-2015 at 00:32

Please describe HOW you came to the conclusion that an item sold as a pure food grade product is something completely different than represented?

Please do identify manufacturer/distributor/seller/brand- enquiring minds want to know.

[Edited on 13-1-2015 by Bert]

deltaH - 13-1-2015 at 02:57

It might be xylitol, a crystalline C5 sugar alcohol very similar to erythritol. Does your substance melt at 92 to 96°C?

Maltitol is another sugar alcohol, it is produced from corn products which might explain the smell. It has a far higher melting point of 145°C.

Sorbitol is a C6 sugar alcohol melting at 111 °C, although it's usually sold commercially as a viscous syrup and not nicely defined crystals like erythritol AFAIK.

Loptr - 13-1-2015 at 13:10

Erythritol is a particular sugar alcohol. What is the problem?

How did you identify it as different from the sugar alcohol, erythritol? (notice the -ol ending)

My guess is your test was you weren't able to successfully nitrate it?

[Edited on 13-1-2015 by Loptr]

Hawkguy - 13-1-2015 at 20:22

Quote: Originally posted by Bert

Please describe HOW you came to the conclusion that an item sold as a pure food grade product is something completely different than represented?

Please do identify manufacturer/distributor/seller/brand- enquiring minds want to know.

[Edited on 13-1-2015 by Bert]

Dude so I'm going to assume its purity by the fact that recrystallized product was the the exact same as the original product, being that its pure, whatever it is. Also, Erythritol is employed in culinary use because of it's similarity to sugar in pretty much most ways, this had many notable differences. The taste was much much weaker, a bit corny, and its smell was also worth pointing out.

The company/ package is Now Foods, but since I didn't order directly from the dudes (packaged and shipped by different group) anything coulda happened. The reason I got it differently is because I didn't want to buy like a whole Kg of it. I'm really cautious to say that they're bad, because for all I know, I could be wrong.

The nitrations actually sorta worked, but not properly. Since ETN wasn't formed, I tried in different ways/ acid proportions and nothing worked. All I got were these floury crystals of a nitrated substance, which were pretty wierd. When heated to their melting point on a spoon over a torch, they would auto ignite and produce powerful flames, like an amateur rocket fuel, about two inches high from only a bit of powder. Apparently ETN is a sensitive primary, this was kinda comparable to Nitrocarbamide/ Urea Nitrate.

Hawkguy - 13-1-2015 at 20:25

Oh yeah dude (Bert) I bought it off Amazon (Canadian eh), but I can't find the same listing or whatever, I assume the guys took it down. What I mean is that specific listing by the dudes was taken off, but the Now Foods brand still has theirs up.

deltaH - 13-1-2015 at 20:34

Please determine a melting point, even if crude, it will help to determine what this is.

Loptr - 14-1-2015 at 07:26

I am pretty sure that erythritol tetranitrate is a secondary explosive that becomes more sensitive on contact with aluminum giving the possible use on the primary side of an explosive train (IIRC). Do notice the tetra- prefix, which means that you have to deal with four hydoxyl groups that need to be nitrated.

You could have an incomplete nitration, and just a lesser nitrated product. You haven't presented any evidence of it not being erythritol, just that you seem to have very little understanding of what you are actually doing.

What were your yields? What was your procedure? Temperature during and between additions of reagents, etc.? We could go on and on.

You need to provide more information, especially what you did and how you know you don't have erythritol.

[Edited on 14-1-2015 by Loptr]

Another issue could be with your nitrating bath. What did you use? Mixed acids or acid/nitrate salt? What concentration were the acids? Do you know the products (right side of the equation) of the nitrating bath to determine whether it would have been effective. Did you take into account the water produced in the reaction?

I think you will find an issue with your procedure, or at least that is what I am convinced of, unless you can prove otherwise.

[Edited on 14-1-2015 by Loptr]

What was the yield of floury powder you received? Perhaps, you do have a good grade erythritol that has an anti-clumping agent added, which is very common. This would cause the yield to go down, and if yields were consistently down, with the assumption you were conducting the nitration with optimal conditions, then we might start to look at your starting material.

[Edited on 14-1-2015 by Loptr]

Loptr - 14-1-2015 at 07:59

Quote: Originally posted by Hawkguy

I have a bit of a pyro side, so I bought a small amount of Erythritol online, from a large brand name seller. I was only planning on making a gram or so of ETN, nothing big, so I viewed the whole thing as chill. Advertised as pure Erythritol, I realised it wasn't at all. I managed to identify it later as a pure sugar alcohol, but the while thing has left me feeling a bit stiffed. Anyone knows what kinda loophole these guys must have found, and how I can sorta avoid/ see/ detect/ whatever it in the future for my transactions?

BTW the sugar smells like fruit and candy corn. If anyone knows exactly what it is, that'd be great too.

[Edited on 13-1-2015 by Hawkguy]

I know that sucrose and H2SO4 alone, without temperature control, will make a caramel smell, which then proceeds to completely dehydrate the molecule producing a few carbon shell fragments from the original sucrose molecule, which I have heard referred to as "sugar charcoal".

[Edited on 14-1-2015 by Loptr]

Gargamel - 7-3-2015 at 07:16

I have a general question about nitration, I think it fits in here:

What will happen if I do a ETN or PETN (or something similar) synthesis using a will working setup, but raise the amount of erythritol say 20 or 40% above the optimum.

What will rather happen?

Would this rather create a lot of water soluble trinitrate, or an amount of tetranitrate and some leftover erythritol?

Bear in mind that the erythritol is added in small steps over some time. At the beginning there will be no excess of erythritol.
When it reaches excess, is it possible that already formed tetranitrate loses some nitro groups to the excessive erythritol?

[Edited on 7-3-2015 by Gargamel]

Hennig Brand - 7-3-2015 at 08:36

It is an equilibrium reaction, so the nitration can go in the opposite direction. For instance, this is the reason that rapid dilution of the nitration acid in contact with nitrocellulose is important following the nitration (to keep the time in contact with an acid concentration that causes reduction in the level of nitration to a minimum). I mention NC simply because it takes more care to dilute the acid quickly in contact with it, but all nitric esterifications are equilibrium type reactions. If you add more erythritol than is optimum you will start to get more lower nitrated products and less tetranitrate. There will always be a mixture of nitrates, but given the ease with which the first nitrate group is added, relative to the second and so on, the largest proportion of impurity would be the trinitrate followed by dinitrate and so on (I think).

Gargamel - 8-3-2015 at 03:35

Thank you again.

Well, I recently did a nitration where accidentally to much erythritol was used and the yield was close to nil. Lots of lower nitrates went down the drain obviously.

That's why this was bothering me. So using to much erythritol is a no go.

Another question about ETN:
When making PETN it seems to be helpful to heat the nitration mix after the reaction has died off.
Is there any reason to believe this is worth trying with ETN?

PHILOU Zrealone - 8-3-2015 at 05:18

Quote: Originally posted by Gargamel

Thank you again.

Well, I recently did a nitration where accidentally to much erythritol was used and the yield was close to nil. Lots of lower nitrates went down the drain obviously.

That's why this was bothering me. So using to much erythritol is a no go.

Another question about ETN:
When making PETN it seems to be helpful to heat the nitration mix after the reaction has died off.
Is there any reason to believe this is worth trying with ETN?

The more impurities (lower nitrated molecules) the higher the difficulty to get a clean cristaline product...the molecules becomes soluble in each other lowering the melting point (freezing point) of the desired ETN...they also increases the solubility of each other into water...
All this will account for low isolation yield!

Gargamel - 10-3-2015 at 01:17

Quote:

the molecules becomes soluble in each other lowering the melting point (freezing point) of the desired ETN...they also increases the solubility of each other into water...

So the lower nitrates can act as emulsifiers, dissolving a part of my good ETN in water?
That's a disturbing thought

PHILOU Zrealone - 12-3-2015 at 12:20

Quote: Originally posted by Gargamel

Quote:

the molecules becomes soluble in each other lowering the melting point (freezing point) of the desired ETN...they also increases the solubility of each other into water...

So the lower nitrates can act as emulsifiers, dissolving a part of my good ETN in water?
That's a disturbing thought

Yes! Emulsifiers, Crystal growth perturbators, solubilisators.

Same is true for solubility of alkanes into water...
In environment sector, people usually don't understand that benzine contains monocyclic aromatic hydrocarbons (BETXS-Benzene-Ethylbenzene-Toluene-Xylenes-Styrene) that are more soluble into water than linear alcanes and that their presence increases the solubility of the later into water manyfold ... that's why alkanes solubility tables in pure water are of no use for estimating possible hydrocarbons pollution.

--> Welcome to the real world

Hennig Brand - 25-3-2015 at 16:47

Quote: Originally posted by Deceitful_Frank

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.

I know the question posted by the OP at the beginning of this thread was made many years ago, but I think I have a fairly decent solution that improves results in a number of ways. Using strong mechanical stirring, such as overhead stirring, general results in less unreacted erythritol and a thinner mix even after the nitration is complete and stirring is stopped. As stated by the OP, the nitration mixture normally becomes very thick and difficult to stir with manual stirring, increasingly so as more erythritol is added and the nitration mixture gets thicker and more difficult to mix effectively. When strong mechanical overhead stirring is used the nitration mixture never seems to "set up" and stays quite pourable. When I first witnessed this thinner mixture at the end of the nitration I figured that the yield would be low, but the yield was always at least as good or better as any nitration previously performed with manual stirring. It seems that the ETN formed is in smaller crystals when strong effective mixing is used and also that nitration products don't accumulate on un-nitrated particles of erythritol, or lower nitrates, nearly as much.

Just recently in the NG thread an erythritol nitration using a homemade overhead stirrer was briefly discussed. Here is a link to the discussion with pictures:

http://www.sciencemadness.org/talk/viewthread.php?tid=949&am...

I see that I already posted about an overhead stirrer from a cordless screwdriver in this thread, however, the overhead stirrer posted about in the NG thread is much better and more of the associated technical issues have been worked out as well.

[Edited on 26-3-2015 by Hennig Brand]

Rosco Bodine - 27-3-2015 at 12:21

Here is a reference of interest describing a mixed acid nitration of ETN and testing of ETN usefulness as a sensitizer for AN based compositions. This reference may have been already posted, but I am not certain so I am attaching it here.

Attachment: ETN as sensitizer for NH4NO3.pdf (201kB)
This file has been downloaded 945 times

Tornadocraver - 30-5-2015 at 16:43

Check this video. The guy added water to the mix before filtering because ETN is insoluble in water. URL: https://youtu.be/HYmCxP2PVVs?t=67

Tdep - 31-5-2015 at 04:49

...yeah? That's what you do. Dump the mix into water, how is this noteworthy?

TheAlchemistPirate - 25-11-2015 at 12:54

Can low temperatures affect the yields of ETN nitrations? I have attempted the (seemingly) simple nitration of erythritol several times, but cannot get decent yields. Here is my method-
20 grams KNO3 are slowly added to 33 ml H2SO4, keeping the temperature under 25 degrees C (obviously). I stir the solution until the temperature doesn't rise anymore, and a precipitate of presumably potassium sulfate is visible, which I ignore. This is where it gets strange. As I start to add 5g of erythritol, no rise of temperature is observed at all. It only takes about 2 minutes to add the erythritol, only pausing to stir it into the mixed acids. It stays at about 8 degrees C, and the mixture only starts thickening after all the erythritol is added, near the end of the nitration period(the 15 minutes after the final addition of erythritol).
I have performed this synthesis twice, and have gotten similar results both times. My yield is supposed to be about 7 grams, but am only getting about 2 grams. I'm using a single coffee filter to collect the precipitate, as I forgot to order proper filters. No precipitate is noticed in the filtrate, however.
My guesses are that either-
1. The nitration temperature is too low. I considered removing the beaker from the ice bath to increase the temperature during the second reaction, but it was freezing outside anyways and I didn't think it would help.
2. The nitration period is too short. This would probably tie in with the above guess, as usually colder reactions take longer. I did notice that the slurry got much thicker near the end of the nitration.

[Edited on 25-11-2015 by TheAlchemistPirate]

Hawkguy - 25-11-2015 at 19:22

Just like with nitrating Phenol, a lot of the time the home chemist didn't fully nitrate the Organic molecule. With Phenol (or aspirin) this probably happens a solid quarter of the time, and with Erythritol slightly less. Its generally a good idea to do a second nitration if the product isn't up to par.

OneEyedPyro - 25-11-2015 at 21:12

Quote: Originally posted by Hawkguy

Just like with nitrating Phenol, a lot of the time the home chemist didn't fully nitrate the Organic molecule. With Phenol (or aspirin) this probably happens a solid quarter of the time, and with Erythritol slightly less. Its generally a good idea to do a second nitration if the product isn't up to par.

That's one nice thing about ETN, the mono, di and trinitrate are water soluble so it's impossible to end up with any significant amount of lower nitrate impurities.

TheAlchemistPirate - 26-11-2015 at 17:17

Alright I attempted the synthesis again today, and have gotten much better results. It seems that I was right on both of my guesses, and both the short nitration length and the low temperatures were affecting my yields. To be honest, I don't know the exact weight of the product as it is still drying on the filter paper, but it has about 6 times more volume than my two gram yield. Also, I also used a different ratio of reactants, so that may have skewed my results.

My newer method:
I used the ratios mentioned by a member earlier in this thread, though his method used ammonium nitrate. I adjusted for the different molar weights by multiplying the amount of NH4NO3 by 1.07, to gain the amount of KNO3 needed. (I know this isn't stoichiometric either, but this adjustment was suggested by another post in this thread). I'll try to make this as compact as possible, as I'm sure the forum is already cluttered by many ETN "recipes" .
30 grams KNO3
50 ml H2SO4
8 grams erythritol
The nitrate salt was added to the sulfuric acid, kept below 25 degrees C (you know the drill). What I did differently here is, when all the nitrate salt was added, I allowed the solution to warm to room temperature. The solution was repeatedly stirred at room temperature, and placed back into the ice bath when needed. I believe this allowed more of the nitrate salt to react with the acid, as the higher temperature allowed the increasingly dilute mixture to completely react. The mixed acids were allowed to cool down again, about 15 degrees C. Erythritol was finely ground to a powder, and regularly added to the solution, keeping the temperature between 15 and 20 degrees C. To achieve this, the solution was brought out of the ice bath, and erythritol was added to the solution until the temperature started rising too much. It was then put back into the ice bath and stirred. Once all the erythritol was added, the solution was monitored at 20 degrees C for half an hour. After crashing and filtering as usual, the precipitate was washed with ammonia. I don't know the exact yield, but as I said above, the volume of precipitate was much greater than with other methods.

As the two above posters mentioned, the culprit was under-nitrated erythritol, which would simply disappear when it was crashed into water.

Hopefully some confused experimenter will find this useful, so I haven't simply posted another kewlish method which just spams the thread. Thanks guys

[Edited on 27-11-2015 by TheAlchemistPirate]

XeonTheMGPony - 5-1-2016 at 18:59

Introduction:

Hello, Ironically I came to join due to a subject I was some how able to view in the whimsy sub-forum, the how or why I was able to is beyond me but I found it gripping but had to register to continue reading it. So here I am! So now I am all joined up I figured I'd share my synth and its quirks of ETN.

The Acid:

500Ml is poured into a 1L round bottom Pyrex flask to be purified/concintrated.

Like most of you I get my wonderful super mega high tech acid from the local big chain (Canadian Tire, any one wanna guess where I am?!?!) store here. It's called ro-tyme Drain opener (The actual name is all lower case!). Like most drain cleaners it is less then clear, to solve this I add 200Ml of 35% H2O2 in 2 steps, first addition of 100Ml is don with the acid cold (0c), the ensuing reaction will heat it up considerably hot and release ozone gas.

(I found the amount of peroxide to add by treating a small 100Ml sample then scalling it up for the main 500Ml batch, by adding peroxide and heating till it yielded clean clear acid in my sample)

I allow this reaction to go on un aided until it is to room temp with intermediate swirling every so oft, once at room temp I add the second 100Ml h2O2 @ 35% then I place on my heating mantle on low heat till no more bubbling is visible, then I increase heat to cook it off to a higher concentration (This process is less then scientific for me, I do about 4H at a volume of 700ml total (Acid + Peroxide) till I see the tell tail dense white acid fumes, I then take off heat and allow to cool to room temp. Then care fully weigh out a precise 100Ml then divide the result by 182 to get my % concentration (Usualy about 95 to 96%)

The end result is a near crystal clear amber fluid of nice viscosity!

The Synthesis:

I have followed the parameters that most have listed, after reading through all the related threads I have used the standard of 100Ml of H2SO4 @ 174grams per 100 Ml (apx 95%)

60grams NH3NO3 sourced from Tannerite, dried and crushed.

I mix this at 0C to 5C during the nitrate addition, once all is added I allow to sit at room temp while I process the Erythritol (Grinding to fine powder and weighing out)

17 Grams Erythritol

Once the Erythritol is ground and weighed I place the acid in the ice bath till at 0C

I then start adding half a tea spoon at a time (I do not have a high accuracy scale so I use volumetric measures at this stage) I mix in fully then allow 1 minute to elapse while stirring between each addition.

Now here where there has been variables, Temp and nitration time ( am still adjusting these to zero in on best yield)

The results:

Out of the 17 I get a consistent 10grams yield!!! Mind you it is very good quality one, befor washing and recrystallizing you can see the nice platelets of the ETN shimmering in the acid!

I crash the mixed acids and products into 200Ml of ice cold distilled water, I then filter out on an unbleached coffe filter and wash with a further 400Ml distilled water then a final stage rinse of 100mL bicarb solution. I then proceed to air dry the crystals.

Recrystallization:

I take 70Ml of Methanol and warm to 40c, I add in some urea (3mL crushed) and stir till fully dissolved, I then take my now dried and powdered ETN and stir into the methanol/Urea mix (If required I filter this to remove any solid impurities and rinse the filter and funel with extra methanol).

Once dissolved and, filtered if needed, I then crash this into 100Ml distilled ice cold water with weak bicarb solution to precipitate out the crystals. This is placed in the freezer for a while to force out as much as possible. Then do the final filter stage.

Final result?:

Beautiful white shimmering platelets of ETN with a perfect melting temp of 61C and gives a solid report when heated and bound in Al foil! Sad part is the 10 gram yield out of 17!

Can any one shed some light on possible errors I am making?

Nitration #1 was half hour at room temp (being 15 degrees) #2 was at 1H after final addition at 5c, then for ten minutes at 20C, both produced 10g out of 17 grams starting material, Acid density/volume and nitrate amount remained static. Both times it was stirred every 5 minutes for 1 minute.

* Edited for clarity.
* Added details to peroxide volume to be added to clean acid and how it was determined
* Added details to the recrystalization section.

[Edited on 6-1-2016 by XeonTheMGPony]

[Edited on 6-1-2016 by XeonTheMGPony]

[Edited on 6-1-2016 by XeonTheMGPony]

TGT - 6-1-2016 at 12:32

ratio of nitrate to erythritol should be four to one.

TGT

XeonTheMGPony - 6-1-2016 at 18:05

Thank you I calculated 68g Nitrate (NH4NO3) for 17g Erythritol, Does this sound correct? I'll increase sulfuric to 110Ml to help with viscosity.

TheAlchemistPirate - 6-1-2016 at 18:50

I won't comment on reagent ratios but your acid and reagent quality sounds fine to me. Of course when testing one variable you shouldn't change other ones while doing so. I would try letting the reaction mixture(with all reagents added) sit at one temperature for a longer period of time (maybe 45 minutes, an hour?).

Also, I'm unsure of what you meant about not having an accurate scale and adding half teaspoons at a time; are you measuring your total solid reagent amounts by volume? Or are you simply using a teaspoon to determine how much erythritol to add at a time? In the former case, I would implore you that a 0.1(or greater) gram scale is an essential piece of lab equipment, in my view the most important apparatus you should buy for home chemistry. Having a good scale can be (and frequently is) the difference between performing an excellent reaction and being able to repeat it, and never being able to repeat your results. In the case of the latter I don't think it matters too much how much erythritol you add at a time, as long as additions are consistent, not any more than about 1/4 of your total amount, and you stir and warm the solution to ensure it has all reacted.

I have only performed this reaction three times, but am getting closer to an efficient method. A big problem seems to be the water-soluble lesser-nitrated erythritols which appear in the reaction mixture, but vanish upon water crashing. If these manage to survive purification, they tend to make a less-powerful, less sensitive product. It sounds like you have managed to filter out (or more likely the opposite if that makes sense) these impurities, since your product explodes when heated on aluminum.

EDIT: It might not have been clear, so I just wanted to say that these lesser-nitrated erythritols(or whatever the proper term is), which would have been ETN, will usually be lost during purification. Again, as the posters above stated, this is a very common reason for lack of product.

[Edited on 7-1-2016 by TheAlchemistPirate]

[Edited on 7-1-2016 by TheAlchemistPirate]

XeonTheMGPony - 7-1-2016 at 04:25

Quote: Originally posted by TheAlchemistPirate

I won't comment on reagent ratios but your acid and reagent quality sounds fine to me. Of course when testing one variable you shouldn't change other ones while doing so. I would try letting the reaction mixture(with all reagents added) sit at one temperature for a longer period of time (maybe 45 minutes, an hour?).

Also, I'm unsure of what you meant about not having an accurate scale and adding half teaspoons at a time; are you measuring your total solid reagent amounts by volume? Or are you simply using a teaspoon to determine how much erythritol to add at a time? In the former case, I would implore you that a 0.1(or greater) gram scale is an essential piece of lab equipment, in my view the most important apparatus you should buy for home chemistry. Having a good scale can be (and frequently is) the difference between performing an excellent reaction and being able to repeat it, and never being able to repeat your results. In the case of the latter I don't think it matters too much how much erythritol you add at a time, as long as additions are consistent, not any more than about 1/4 of your total amount, and you stir and warm the solution to ensure it has all reacted.

I have only performed this reaction three times, but am getting closer to an efficient method. A big problem seems to be the water-soluble lesser-nitrated erythritols which appear in the reaction mixture, but vanish upon water crashing. If these manage to survive purification, they tend to make a less-powerful, less sensitive product. It sounds like you have managed to filter out (or more likely the opposite if that makes sense) these impurities, since your product explodes when heated on aluminum.

EDIT: It might not have been clear, so I just wanted to say that these lesser-nitrated erythritols(or whatever the proper term is), which would have been ETN, will usually be lost during purification. Again, as the posters above stated, this is a very common reason for lack of product.

[Edited on 7-1-2016 by TheAlchemistPirate]

[Edited on 7-1-2016 by TheAlchemistPirate]

I most certainly agree, a 000.00 scale is critical, and I am waiting for it to arrive! ATM I have a scale with 1g resolution (Better then my refrigeration scale with a 10g res!) Some point I'd like to buy a good lab grade scale with a .0001g resolution, but that will be pricy but critical.

Ironically (Being as atm I do not have one my self (Yet!)) It is Vital to have an accurate high resolution scale! Experience can only compensate so much for lacking of the correct tools! But with care full grinding (All ways sieve what you grind for consistent particle size) and volumetric measures can at the very least be fairly consistent.

So for the additions, I am using volumetric measures for the Erythritol that has been sieved.

So the next synth I will use 110Ml of Sulfuric at 95%, 68g of NH4NO3, and the 17g Erythritol.

Mix nitrate and acid at 0c, then let sit for 30M @ 20C. Chill to 0C and then add my Erythritol at half a tea spoon per addition every 1 minute under constant stirring. After last addition will react at room temp (15c) for 1H with stirring every 5M.

I'll report back with final yield after weighing in on the dried recrystallized product.

M = Minutes
H = Hours
C = Celsius
G or g = Grams
Ml = Milliliters

As for the Lower nitrated amounts of material being lost, this I understand, what I do not yet quit get is why I am failing to get good nitration, but we'll see with the corrected nitrate to sugar ratio does, then I'll revamp procedure to a higher temp nitration (15C+ for the whole thing). Hope fully at the very least I'll break even on the sugar side and get 17g product for my 17grams sugar!

* Edit: Added table for abbreviations
* Spelling
* Added further paragraph.

[Edited on 7-1-2016 by XeonTheMGPony]

[Edited on 7-1-2016 by XeonTheMGPony]

Bert - 7-1-2016 at 21:34

Perhaps report volumes in cc rather than obsolete Imperial volumes (teaspoons)... Try to give all measurement in SI?

https://en.m.wikipedia.org/wiki/International_System_of_Unit...

A digital scale with 10 milligram resolution is cheap, and quite good enough for what you're trying to do.

http://www.amazon.com/Frankford-205205-Parent-Arsenal-Reload...

XeonTheMGPony - 8-1-2016 at 03:57

Quote: Originally posted by Bert

Perhaps report volumes in cc rather than obsolete Imperial volumes (teaspoons)... Try to give all measurement in SI?

https://en.m.wikipedia.org/wiki/International_System_of_Unit...

A digital scale with 10 milligram resolution is cheap, and quite good enough for what you're trying to do.

http://www.amazon.com/Frankford-205205-Parent-Arsenal-Reload...

I know what SI is how ever to properly describe what I am doing is to well, accurately describe it, is this perfect most certainly not how ever it is a true rendition of the events taking place

Here is more functional link then that generic description Of the SI system:
http://www.metric-conversions.org/volume/teaspoons-to-millil...

As for the scale issue if you have a re-read you'll see that one has all ready been ordered with said resolution, how ever that is not good enough for my liking, Accuracy is every thing,

BTY This is all off topic to the parrent thread.

For those whom may be interested apx volume of a tea spoon is 5Ml rounded to the highest and the apx range of a half tea spoon would be 2 to 3 Ml (I was not doing very precise measures hence my choice of a generic figure of "half teaspoon") All other measures for weight are within .5grams

[Edited on 8-1-2016 by XeonTheMGPony]

[Edited on 8-1-2016 by XeonTheMGPony]

XeonTheMGPony - 14-1-2016 at 09:20

After some further reviews I committed the error of not paying close enough attention! Turns out the Erythritol I was using included Stevia extract!

Following the procedure laid out here: http://www.sciencemadness.org/talk/viewthread.php?tid=26679

I successfully recrystallized a much more pure feed stock.

I used the same 100Ml of 95% sulfuric acid and I kept the 60G of NH4NO3 measures intact so I can track the efficiency better

I Nitrated for 2H, started the first hour at low temp of 0C to 10C, then the final hour at 17C to 20C

I used 17G of The purified Erythritol, and yielded raw dry powder weighing in @ 22.57G and after recrystallizing a Net of 19.9G with 2.67g loss due to spillage and entrapment in the filter media (New scale arrived so I can track losses n such much better now!)

Crystals are free flowing with a nice snow white color!

Thank you all for your help, I will now do the next synth following the 4 Nitrate to 1 Erythritol rule, to see what changes that makes to nitration time.

Out line of procedure:

100Ml Sulfuric acid @ 175.5G per 100Ml
60G of Ammonium Nitrate
17G purified Erythritol

Acid was chilled to -10c, a salted ice bath was prepared during this time.

Acid removed from freezer then placed in the salted ice bath, half a teaspoon (ruffly 1 - 3Ml)(Yes still doing this ruff shot for expediency) of nitrate is added, and stirred vigorously till all is dissolved befor the next addition, First half of the addition is don every 1.5m then after that I go as fast as it will dissolve with out raising temp.

After last addition I stir for 2 additional minutes then place to the side to warm to room temp as I weigh out and mill the Erythritol, I reweigh the Erythritol post milling to adjust for losses.

With the Erythritol milled and weighed, I place the acid mix back in a fresh salted ice bath and stir till at or below 0C, I then add half a teaspoon (1 to 3Ml apx) whilst stirring, Once dissolved I wait 1m befor next addition. Repeat till it is all added.

Once all is added I stir for 5m then let rest and stir in 5 minute intervals for 1H. After the one hour has elapsed I remove from ice bath and allow to rise to room temp and stir every 5 minutes for another hour. (Please note that the ice bath IS NOT discarded at this point, it will be required should temps rise more then 20c)

After 2Htotal time (Including addition of the Erythritol time) I crash in 200Ml iced distilled water while stirring the water.

This is then filtered and washed with 500ml distilled water, then with 1l of RO (Revers Osmosis) water. Once water is drained it is placed in a warm air bath @ 30C to fully dry.

Recrystallization:

100Ml of Methanol Hydrate is measured into a beaker, to this 225mg of Urea is added (I find this number by multiplying the raw product dry weight by 1%). The methanol and Urea are mixed in a hot water bath at 60C till all is dissolved, I then add my dried product till all is dissolved thoroughly.

I then filter into 200ml of room temp (16c) distilled water that had 225mg of Urea and 5ml of sodium bicarbonate dissolved into it.

This is then filtered and further washed with 200ml of cool distilled water, befor final drying.

As the old saying goes, Pics or it didn't happen! First one is the Nitrated product, the other is the purified Erythritol!

Thanks for such an awesome forum and the help people!

[Edited on 14-1-2016 by XeonTheMGPony]

Bert - 14-1-2016 at 09:50

Pretty crystals. Maybe you should post a copy to the crystal growing thread-

http://www.sciencemadness.org/talk/viewthread.php?tid=64907

Could you take photo on graph paper and state division size, or put a mm scale in picture? Curious how big those are.

XeonTheMGPony - 14-1-2016 at 11:07

Sadly no graph paper but I'll dig through what is left in my drafting box, I should have a ruler some where in there! Will take another pic with the ruler for ya. They where what was left in the mother liqueur (I do cooking too, so saved the tailings for sweetener and they grew over night!) Nice not having wasted any of it!

Test result one; Compressed in foil then heated:

New purified feed stock had a 5 fold increase in power! finger is sore from a very very small amount!

I think that was my main issue was the Stevia contaminant!

Only had a good imperial one but here it is. All so posted in sugested thread.

[Edited on 14-1-2016 by XeonTheMGPony]

Purifide Erythritol crystals-Size 02.jpg - 123kB

[Edited on 14-1-2016 by XeonTheMGPony]

TheAlchemistPirate - 14-1-2016 at 15:45

That's strange, when purifying my erythritol from stevia I found that very little impurities were on the filter paper, and questioned the necessity of purification in the first place...
Honestly I'm still having trouble with this reaction, I'll have to try out your method.

XeonTheMGPony - 14-1-2016 at 16:16

first 3 synths where with unpurified truvia, the color was off white and piss poor yield but good power.

The synth with the purified dried Erythritol produced pure white product and the power was magnitudes higher! a tiny amount completely shattered the aluminium foil shell and shock wave hurt my finger! With very good yield.

So I can say with out doubt the purification is vital!

I regret not taking a premix picture showing the color difference between this synth and the last 3.

during the purification there was zero residue from the truvia, well aside from the sugar its self.

But the recrystallization of the ETN the residue is large amounts of fur! amazing how it gets every where! Along with some Ammonium sulfate that didn't get washed out during the first stage.

If you are referring to the filter paper in the picture they are just fines that where statically stuck to the paper, and where not worth the head ache to recover every super fine particle.

I need to work on my recrystallization method to make a larger denser crystal, that will resolve the post processing losses due to ultra fine crystals.

[Edited on 15-1-2016 by XeonTheMGPony]

[Edited on 15-1-2016 by XeonTheMGPony]

markx - 15-1-2016 at 06:13

Quote: Originally posted by XeonTheMGPony

I need to work on my recrystallization method to make a larger denser crystal, that will resolve the post processing losses due to ultra fine crystals.

Instead of filtering the hot concentrated recristallisation solution (ETN+MeOH or EtOH) and letting it drip into water you could just filter it into another container and then cool it down in deep freeze to percipitate the product as dense transparent flakes. Then separate the cold solvent by filtration and wash the product with plenty of water. This procedure yields a very nice flake form that compresses easily and effortlessly.

Bert - 15-1-2016 at 08:17

Quote:

a tiny amount completely shattered the aluminium foil shell and shock wave hurt my finger! With very good yield.

You deliberately cooked off a high explosive- with hands close enough for that to happen.

I suggest you stop doing that, use a ring stand or similar and get away.

Next, will you will tell us how long your (unprotected) ears rang? Or that there are bits of foil in your eye because you were not wearing safty glasses/face shield?

XeonTheMGPony - 15-1-2016 at 12:43

that is the point hand was not that close! and when I say very small I do mean small, I've worked with HE's in the field so I know their power and abilities quite well, I was in no danger of injury, just surprised by the power increase over the last few runs!

FYI Remember what assumptions make you

In the remote logging camps you mess up you die, just that simple, being I am still here with all parts attached means I been doing some thing right!

Usually I use a candle but I figured the scrappings from the table and being smaller then the size of a salt grain the risk of using a bic lighter was marginal. FYI The charge was held in pliers, it was the hand with the lighter that felt it hurt is the wrong word for it but it is the closest discriptor I can think of.

In terms of safety I'll be posting pics in one of the threads dedicated as such for others to illustrate how unforgiving these substances are with a cow thigh bone (Got them for the dogs, but they since abandoned them).

I do not take risks! (Not even speeding!)

[Edited on 15-1-2016 by XeonTheMGPony]

XeonTheMGPony - 23-1-2016 at 07:52

Batch #5

17.03 grams erythritol purified from Truvia
68.05 grams Ammonium Nitrate
110 Ml Sulfuric acid @ 178.23g/100ml

Process:

Weighed out the sulfuric acid into beaker then placed in freezer.

Weighed out ammonium nitrate prills, Sieved out the finer particles then placed remaining material in mortar, crushed and sieved till all was equal in particle size (Mortar was warmed in oven to help reduce moisture up take)

Weighed out Erythritol (recrystallized), sieved and then milled in mortar (Same process as nitrate)

Rechecked weights of material after processing.

Prepared ice bath (Large container of snow saturated in a weak salt solution)

Placed my acid into ice bath, Added nitrate at 5ml increments, each addition was don after the first had fully dissolved, after slightly over half of the nitrate was added and when each addition no longer caused a temperature spike I removed from ice bath.

After the last addition had fully dissolved I continued stirring for 5 minutes and allowed it to come to room temp (15c) at this point I allowed to sit for 30 minutes at 15c.

After 30 minutes elapsed I then stirred for 1 minute then began adding the erythritol in 5ml increments, following the same method as for the nitrate, once the each addition had fully dissolved and the temp spike started to drop I'd add the next one, with the exception is I did it at a sufficient pace to drive the temp to 20c and I held it here through the addition phase.

After last addition I stirred for 5 minutes continuously then allowed it to rest with a stir every 5 minutes for a total time of 1.5h measured from the start of the erythritol additions.

I then crashed into 200ml distilled water, stirred for 5 minutes, added an additional 100Ml then filtered out the crystals, this is then washed with 1.5L of RO water with a final wash of 500ml distilled water.

After drying gross yield is 22g
After recrystallizing 20.3g (With some remaining in the methanol/water mix that I'll recover upon next batch)

Note: Recrystallization was don with 1% urea as stabilizer and acid scavenger in both the methanol phase and water phase for a total of 2% of the gross weight of etn.

It seems the feed stock (Truvia) was my issue all along! The final crystals of E.T.N where beautiful snow white and free flowing, still very light and fluffy so a small loss was incurred by particles clinging to surfaces n such but over all huge success!

So this is the second batch following the purified feed stock with stellar results, the only change was the nitrate ratio, I went from 60g to 68 grams, the only real difference I saw was a slightly shorter nitration time but that could been altered by the higher nitration temps.

Next batch will be don the same but this time I will again use only 60g of nitrate to try and see what the difference is! I placed an order for 1pound of pure Erythritol at a local health/hippy supply store so if I can get same results with less nitrate usage it will pay off nicely.

So again Thank you to the members suggestions and tips, and for this whole thread, it was instrumental in be developing the procedure and fine tuning it!

XeonTheMGPony - 24-1-2016 at 18:17

batch 6:

60g nitrate all ells remained the same, 13g yield, so one must follow the 4 to 1 rule of nitrate to sugar! T get full yield as has been reported.

XeonTheMGPony - 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!

Why oh why?

Herr Haber - 4-2-2016 at 21:05

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

XeonTheMGPony - 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]

Aurium - 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.

XeonTheMGPony - 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!

Laboratory of Liptakov - 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.

Aurium - 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?

NeonPulse - 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.

XeonTheMGPony - 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.

XeonTheMGPony - 16-8-2016 at 09:32

The product of said math and following synth

Melgar - 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.

XeonTheMGPony - 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.

What about 65% HNO3 ?

Tricka90 - 10-10-2016 at 12:46

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]

greenlight - 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.

Tricka90 - 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]

greenlight - 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?

Tricka90 - 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]

greenlight - 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.

Tricka90 - 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]

hissingnoise - 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.

Laboratory of Liptakov - 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.

Tricka90 - 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.

OneEyedPyro - 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.

NeonPulse - 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)

Tricka90 - 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]

Laboratory of Liptakov - 12-10-2016 at 03:59

My preparation was this: Cool acids on zero. And partially added, for example 1g Er. every 3 minute. And hold temperature between +3 to +5 Celsius. Thus for 10g Er. 10x by 1g Er. After adding 10g is possible instantly or slowly increase temperature on +15 C. And continual stir mixing still 15 minutes. Yield should be 20g ETN +. Dr.

Tricka90 - 12-10-2016 at 04:30

@Laboratory of Liptakov:
Thanks a lot for your feedback. Did you get that yield using 96% H2SO4 and 65% HNO3 or using 98% H2SO4 and higly concentrated HNO3?

Laboratory of Liptakov - 12-10-2016 at 12:35

H2SO4 96% and HNO3 65 %. Normal concentrations for classic nitration or esterification process.

Tricka90 - 17-10-2016 at 04:51

That's great thank you.
I was wondering, what if one wants to make very small batches of ETN? The quantities I posted before (4ml 65% HNO3, 6ml 96% H2SO4, 1g Erythritol) would lead to about 3 grams of ETN which is a huge amount in my opinion, considering only 1 or 2 grams are needed to detonate very large amount of let's say ammonal.
For example if you wanted to make only 300 mg ETN how would you operate? You could scale down the quantities but it would be very impractical to work with less than 1 ml of solution.
Do you think would be a good idea to just scale down the Erythritol amount to let's say 100 mg and keep the same amount of acid (4ml 65% HNO3 and 6ml 96 % H2SO4) in order to obtain only about 300 mg ETN? Or maybe too much acids for that little dose of Erythritol would cause problems?

Tricka90 - 19-10-2016 at 13:47

No one knows the answer?

Metacelsus - 19-10-2016 at 15:15

It's not "very impractical to work with less than 1 mL." The scale of 10 µL is where it gets difficult. However, making 300 mg ETN isn't any harder than making 3000 mg.

Bert - 19-10-2016 at 18:57

Given a good grasp of technique, sub gram quantities are not too hard. If you are at all sloppy, inexperienced or just under equipped, you do risk throwing a large % of baby out with the bath water, of course. See member Microtek, past master of the tiny scale EM synthesis and device implementation.

One may want to consider: Is the chance of experiencing a personally dangerous outcome more a function of number of times an opporation is repeated, or of the size of the batch being run??? I do not have a hard, definitive answer, but do know that if an operation is repeated enough times, anything that CAN go wrong, DOES.

Is it statistically more dangerous to make 300mg 10 times, or 3g once? 300mg detonated in close enough proximity will still fill your face with glass particles or remove some fingers. 3 grams, all of that plus bothering the neighbors.

Tricka90 - 21-10-2016 at 01:01

I'm sorry, I should have said it is very impractical FOR ME, since I don't have the proper equipment nor the experience required to work with very tiny batches.

Bert, your statement is very sound and I agree with you about the greater risk of accident relative to the making of 300mg for 10 times instead of 3g for 1 time. But accidents must always be expected and accepted in my opinion: I always force myself to work in a manner that guarantees I won't get permanently hurt even if an accident does occur, at any point during the process. When making a few hundreds mg that is fairly possible if very good body and hearing protections are used and proper distance between the explosive and the hand (at least 10cm) is always kept during the whole process. When working with some grams instead, the required protections and distances would be way more severe, so the process would be much harder to fulfill. That's why I prefer making small batches many times expecting detonation anytime than big batches a few times supposing they won't detonate, I think that's what makes a difference between a long and satisfying career and a short one...

So if I wanted to work with smaller batches would you advise me to just scale down all the three ingredients (erythritol, HNO3 and H2SO4) or is it possible to just scale down the erythritol quantity? An higher ratio of acid mixture and erythritol would be a problem in your opinion?

XeonTheMGPony - 21-10-2016 at 08:26

Following proper procedures and using good reagents, and care full monitoring of temps there is very little risk! Careless and sloppy work will increase the risks.

Ironically working with smaller reaction masses increase the risk, as temps can change very fast in a less controllable fashion, with a larger reaction mass you have the benefit of thermal mass to buffer reaction temps.

So I say practice with 3g amounts, and plane your experiments out care fully in advance make sure to have a good thermometer, clean glass wear, and bicarb water, and a wet sponge with it (Clean up any spilled acids on your self or the work surfaces).

There is no such thing as a dangerous substance, just dangerous people!

Tricka90 - 28-10-2016 at 06:01

Thank you, you definitely have a point, I didn't consider that reaction's inertia, which decreases with reagents masses, could cause problems by producing sudden changes of parameters such as temperature.

I have some questions about the neutralization step which has to be done right after the powder is filtered:
- Is it possible to not noticing any fizzing when ETN is washed with sodium bicarbonate solution? (maybe because it was previously washed with a plentiful amount of water)
- What if ETN is continued to be washed with sodium bicarbonate solution for a long time after the fizzing has stopped? Can it be detrimental to ETN properties?

[Edited on 28-10-2016 by Tricka90]

OneEyedPyro - 28-10-2016 at 07:37

Quote: Originally posted by Tricka90

- Is it possible to not noticing any fizzing when ETN is washed with sodium bicarbonate solution? (maybe because it was previously washed with a plentiful amount of water)
- What if ETN is continued to be washed with sodium bicarbonate solution for a long time after the fizzing has stopped? Can it be detrimental to ETN properties?

[Edited on 28-10-2016 by Tricka90]

Yes, of course the acid contaminants can mostly be removed by washing with water due to their highly soluble nature.

Washing with a bicarb solution for extended periods likely won't help neutralize the ETN any further but it also isn't going to hurt anything either.

No matter how well the ETN is neutralized with bicarb solution there will still be acids trapped within causing decomposition so it should be recrystallized ASAP.

Also, you seem more cautious than what is reasonable.
I don't even think an accidental detonation of ETN is possible during synthesis.
I've purposely let nitrations runaway many times just to see what would happen, the result was lots of NO2 and nitric acid vapors but never an explosion.
The dehydration and oxidation appears to destroy any ETN that may have formed, once everything calms down you're left with a flask of what appears to be mainly carbon and sulfuric acid.

I understand being cautious but working in 300mg amounts and being afraid to handle even that quantity just seems silly.
ETN isn't going to spontaneously detonate, under ordinary conditions the danger is quite minimal.

[Edited on 28-10-2016 by OneEyedPyro]

greenlight - 28-10-2016 at 08:40

I don't think runaway reactions of ETN on the scale that people on here perform it on can lead to an actual detonation. The risk is with large commercial batches I think and I especially would not worry about a 300mg batch.

I agree, don't lose your cautiousness when doing these sorts of things but you don't have to be that paranoid about a 300mg batch that's for sure.
It is nice to see some people on here that are cautious, some peoples posts that have come and gone have been shocking (starting nitration and leaving it overnight in bedroom, runaway nitration reactions in soda bottles).

Tricka90 - 29-10-2016 at 13:47

Thank you for all the help, I really appreciate it.
Yes, I know, maybe I'm too cautious, but I'm just a beginner, maybe I'll develop some more self-confidence later.
Talking about neutralization, as a general rule of thumb how much milliliters of sodium bicarbonate solution (saturate) do you think are needed for gram of ETN? I know that's kind of a difficult question as the quantity could vary a lot from time to time, but I would like to have just a humble guideline.
About recrystallization, I've heard that using ethanol from pharmacy/drugstore is even better than using laboratory grade ethanol because the one sold in pharmacy also contains anti acid compounds, what do you think about it?

OneEyedPyro - 29-10-2016 at 20:04

It really doesn't matter, for a 25 gram batch I would wash it with about a 500ml of tap water followed by 500ml of bicarb solution and finally a quick rinse with more tap water.

As far as alcohol you can use just about anything, even 70% isopropyl alcohol works decently.
I'd suggest whatever's cheapest.
Remember, recrystallization can be safe or very dangerous depending on your procedure.

Heating a highly flammable solvent that's nearly saturated with ETN in a glass container over a naked flame is full blown darwin award material, yet someone here did exactly that and lost a hand as a result.

I recommend heating some water to about 65C, remove it from heat and away from any possible ignition sources then place your container of alcohol into the hot water, begin adding your ETN bit by bit with gentle stirring making sure not to allow it to settle to the bottom and pool up. Once it's all added you can filter the solution if their appears to be any insoluble impurities, now dump it into 10 times the volume of distilled water with rapid stirring. You can optionally add a few percent urea to the water as a stabillizer, a few percent sodium bicarbonate can be used if you can't find urea.

Tricka90 - 29-10-2016 at 23:16

Thanks a lot OneEyedPyro for the detailed explanation, I'll definitely follow your advices.
The only thing I'm afraid of is recrystallized ETN seems to be more sensitive than non-recrystallized ETN, or at least that's what I've read. If that's true I wouldn't do anything to increase the sensitivity of ETN which is too sensitive already... What do you think about it?

OneEyedPyro - 30-10-2016 at 01:11

Sensitivity to impact varies a lot based on crystal size, ETN as a very fine low density powder is quite insensitive to impact while large dense crystals will be significantly more sensitive. The method of recrystallization I mentioned yields a very fine powder if done right.

Unrecrystallized ETN can be unpredictable and has a very short shelf life, recrystallization is an absolute necessity in my opinion.

It may be sensitive compared to many other secondaries but no reasonable amount of friction or impact will set it off.
As a fine powder you can place it on a concrete floor and drag a hammer across it with all of your weight and nothing will happen, you could literally wrap it in foil run it over repeatedly with a car and again nothing will happen.

The biggest danger ETN presents is its ability to undergo DDT when ignited or strongly heated. Good charge design is important, if stray sparks from the fuse somehow fell onto the ETN prematurely it could detonate but even that is unlikely.

Now as long as you don't do anything drastic and maintain a reasonable level of respect for it I don't think you'll have any issues, in fact I predict you'll have issues actually getting it to detonate

Tricka90 - 30-10-2016 at 01:44

Thank you again OneEyedPyro

All your advices are very informative and helpful, you definitely have matured lots of experience on the subject!
How much ethanol per gram of ETN is needed, in your opinion, to accomplish your recrystallization process? I think 10ml 95% ethanol per gram of ETN should be appropriate and then, after filtration, 10 times volume of water should be added, as you said, so it's 100ml water if my guess is correct.

greenlight - 30-10-2016 at 08:08

Quote: Originally posted by OneEyedPyro

Now as long as you don't do anything drastic and maintain a reasonable level of respect for it I don't think you'll have any issues, in fact I predict you'll have issues actually getting it to detonate

You got that right. I don't use ETN but I do use PETN which is also a secondary with debatable sensitivity.
I plasticize mine and a few times I haven't had as powerful detonator as I usually use with me and it has blown the explosive around in chunks with no detonation at all...
Have also had a couple of low order dets from weaker caps.
So yeah, I wouldn't worry too much....

OneEyedPyro - 30-10-2016 at 23:17

Tricka. To be perfectly honest with you I've never bothered to do exact measurements.
I simply added ETN until it was having a hard time dissolving then added a bit more hot methanol from a second container in the hot water bath.

I always dumped the solution into the water rather than the other way around.
It's important to pour the solution slowly while stirring the water or the precipitate tends to clump, I found an easy way to avoid this by stirring the water as to get it quickly swirling clockwise while slowly pouring the solution in a counter clockwise motion.

The only problem is that the precipitate is so fine that it's hard to filter, it tends to clog the filter paper a bit and some even escapes through. It makes handling it a bit messy and it can become airborne easily, it does however press nicely and the friction/shock sensitivity is quite low.

Tricka90 - 2-11-2016 at 06:31

Thank you greenlight and OneEyedPyro.

@OneEyedPyro: your recrystallization process seems very safe to accomplish! However since safety is its main priority I think yield won't be optimal, is that correct? If ethanol were heated up by direct flame until boiling point and then ETN were added until saturation then it would be easier to obtain higher yields (but it would be way more dangerous as well!). On the other hand doing your procedure, that is warming ethanol to an initial temperature of about 60°C and letting it decrease a lot during the addition of ETN while staying away from saturation would be way harder to obtain higher yield. What do you think about it? What's the usual yield you use to obtain?

p.s. I agree with you of course: safety first.

XeonTheMGPony - 2-11-2016 at 09:15

it is really simple heat up alcohol, dump in ETN, keep warmed until alcohol volume goes down if you need it to, slowly dump into twice the volume of stirred ice cold water! Filter, dry, store.

At this point there is no effect on yield! you get out what you put in - the acid.

I use 1% by mass urea in the alcohol solution, and 3% by mass urea in the water solution to help act as a stabilizer and acid scavenger, some use ammonia.

I use methanol my self, some times when I want to skimp on the methanol I use an acetone blend, then I drive off the acetone from the methanol then reduce methanol volume and very slowly cool to grow high density crystals, for light fluffy crystals use above technique.

Erythritol Tetranitrate Lab Notes

EWillies - 18-12-2017 at 18:57

Hello everyone,

I realize there are many threads on ETN, however I had a pretty smooth synthesis today and thought I'd share my lab notes. It has been years since I've synthesized any energetics as I've been out of country a lot but there is an opportunity to blast some unwanted beaver dams and stumps at a friends farm. So I jumped at the prospect of rendering my services. The project doesn't kick off until next year, but I promise I will return with footage and pictures.

I'll be producing some Nitroglycerine as well. I'll be mixing it with Acetone with a 70/30 mixture to desensitize it and utilize it for making 8 gram booster charges. I'll post those results as well.

Materials:
250ml Sulfuric Acid 98% Lab Grade
130g Ammonium Nitrate - Powdered in grinder
40g Erythritol

The reaction vessel was a 500ml Pyrex beaker immersed in an ice bath. I added the AN slowly over a period of about 45 minutes. I was careful to not allow the temperature to rise above 15* C at any time. A magnetic stir bar was used to stir the nitrating mixture.

I allowed the mixture to stand for 20 more minutes after the final addition of AN and turned the stirring speed to maximum. This ensured all AN was dissolved and the solution was clear. Nitric Acid fumes were present but removed with fume hood.

After the nitrating mixture cooled to 10* C, I began adding Erythritol slowing, keeping the temperature at 10* C. The entire addition took about 15 minutes. I then let it stand for 20 more minutes, stirring occasionally with a glass stirring rod. At this point the mixture had become so thick with ETN crystals that the stir bar was not working.

I crashed the nitrating mixture into a 3000ml glass beaker filled with ice cold water and 10 grams of sodium bicarbonate. There was substantial amounts of bubbling due to the acid contacting the bicarb, but it did not flow over the edge.

I then gravity filtered the precipitate using filter papers and discarded the waste. I rinsed the product with a few liters of bicarb solution. I was impressed with the yield as it appeared to be quite good considering I had used the nitrate salt method. (I need to do another Nitric Acid synthesis if I ever buy a new condensation column after breaking mine :mad:

)

I then took the crystals and dissolved them in Acetone. I would have preferred Ethanol, but I'm working with what I got. It took about 200ml of Acetone to fully dissolve the precipitate.

After cleaning the 3000ml Beaker, I filled it with ice water and dissolved 15 grams of Sodium Bicarbonate. I then crashed the ETN in situ into the cold water and used a large stir bar to stir. The ETN recrystalized and was filtered from the water. The crystal structure obtained from using Acetone isn't as desirable as what is achieved with Ethanol, but it is still acceptable. I may just make blasting gel by dissolving in some Nitroglycerine in which case it won't matter, but we'll see. pH paper was used to test for residual acidity.

The crystals were then dried and stored in a dry, cool place. Final dry weight was 48 grams. I was a bit lazy when rinsing the crystals so I probably could have gotten a few more grams if I had been more careful. Overall, a pretty damn good yield.

Notes:

In past ETN synthesis, I have had a problem with low yields. I believe this was due to allowing the nitrating mixture to become too warm (over 15*) which has a negative affect on the production of Nitric acid while adding a Nitrate salt. So for beginners, watch your temperatures and take your time.

When allowing the nitrating bath to stand after adding the Erythritol, I think it's important to keep an eye on your product and stir. If done correctly, at the end of 20 minutes, the mixture should be so thick with ETN crystals that you think you'll break your stirring rod. Don't let it stand too long, I've had product begin to decompose from being left in the acid too long.

Always always recrystallize your energetic materials. It can be a pain in the ass, but not as much of a pain in the ass as when you don't do it and half of your product decomposes overnight. It also ensures a more pure product, which mitigates risk of sensitizing your energetics inadvertently. Also always test your final product with pH paper before drying.

Anyway, hope this will be helpful to some. I'll post my lab notes for the Nitroglycerine and primary synthesis and eventually the results of my blasting expedition. I look forward to some feedback :cool:

PS : Attached is a photo of the final product.

[Edited on 19-12-2017 by EWillies]

XeonTheMGPony - 19-12-2017 at 03:31

Seems pretty low, I did allot of 17g runs and usual return was 23grams products that no3 group is weighty.

I found allot more comes out of the first crash mixture when allowed to stand for a day, so after filtering I keep that water in a storage jug for refiltering

Microtek - 20-12-2017 at 03:55

Indeed, it is less than 50% yield. The theoretical yield from 40 g erythritol is 99 g, and nitration of alcohols are typically high yielding; PETN synthesis from WFNA and PE usually gives me more than 95 % theoretical.
I think the nitration system is to blame - IIRC, I have had quite reduced yields using AN/H2SO4 in mannitol nitrations.

Bert - 20-12-2017 at 05:20

You did a synthesis, got some of the intended compound AND you took notes... Congratulations, and thanks for posting.

I have merged your posts with a related existing thread, as some already noted, the reported % yield was well below theoretical, there is quite some discussion on that here.

Here is the FAQ regarding posting, generally you should look for a closely related existing thread unless you have something new and different.

http://www.sciencemadness.org/madscifaq.html#2.1_Board_topic...

Quote:

If an existing thread covers the topic you're about to post about, post in that thread instead of a new one. It makes it easier for members to keep up with topics of interest. You may need to search before posting if you're unsure whether or not a thread already exists. The search engine is not very powerful and may miss relevant threads, but please make at least a cursory effort.

(Edit, after the BATF interview)

(Download the orange book, ignorance is never a valid excuse-)

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Additionally, you will want to restrict your posting to chemistry, physics and engineering related to your subject, this is not where you want to post crater videos and such, go to YouTube if you absolutely must.

We don't let organic chemistry posts stray into balls out meth lab implementation/my last batch of fentanyl posts, the energetic section is not for weapons demos or other illegal applications.

Pardon me, I just spent 2 hours since initialy posting this in our office with a BATF agent. Not because we did anything wrong, just a license renewal.

Possibly I am a bit on edge, but PLEASE don't post about blowing up beaver dams in the USA with explosives made not on day of use (manufacturing license, storage magazine, record keeping? BATF!), not at site of use (shipping explosives with no EX#, transported on public roads unplacarded, by a non Hazmat licensed driver with no bills of lading? DOT and PHMSA!) and most especially, doing this for any kind of compensation ("in commerce" MATTERS- Both to DOT for transport of reportable quantities of Hazmat and BATF for engaging in an explosives related business without a license).

Another piece of the FAQ:

Quote:

Do not request spoonfeeding of information for clandestine drug manufacture. However, every sort of chemistry is a permissible topic of discussion if you discuss it like a scientist. If someone is asking about obtaining chemicals used in drug manufacture and using the vocabulary of a SWIM—"someone who isn't me"—-mer more than a chemist, report it and the thread will be dealt with after a moderator has confirmed your findings. Similarly, if someone is asking for help with a synthetic "recipe" for a known street drug, report that too. Don't bother to berate the cooks in the thread itself instead; that doesn't bring the mods any faster. In truth the mods and most members dislike any thread where someone is seeking or using a "recipe" and doesn't show any deeper interest in chemistry, but this has been mostly a problem with drug synthesis because of the many people who want to quickly get rich or high.

Certain topics are unwelcome no matter what section they are posted in. The discussion of criminal enterprises or weapons production is inappropriate.

[Edited on 22-12-2017 by Bert]

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