Sciencemadness Discussion Board

ETN Synthesis/Yield Problems

jack3k3 - 12-7-2010 at 17:15

On my third synth of ETN, I have come to notice, in comparison with other pictures of ETN yields, that mine is a white cake precipitate. Typically I filter with coffee filters and then close them and squeeze to get out more liquid, this might leave the thick/clumpy residue, but even upon drying it doesn't seem to be a crystal form.

I do use water crash and baking soda/water crashes for neutralization, this is all prior to crystallization as I don't have the necessary items to perform that yet.

I have tested the white cake when it is dry and it did detonate with al foil/hammer test but not with the noise I had expected (something similar to a small firecracker for a bit larger than a pinhead). So I am just wondering if there may be a problem or if this is normal? (my reactants are kno3 from greenlight stump remover ground in coffee grinder, 100% pure eyrthritol ground in coffee grinder, and sulfuric acid (rooto professional strength))


P.S. One other question, I recently had a synth go bad (I believe) as when adding KNO3 to the sulfuric, it started to heat and got extremely thick and temp shot to 27C despite lots of stirring and ice bath. Although I figured this would be a failure I brought the temp down after a minute or so and proceeded to add the erythritol but had to cut nitration to only 35minutes as there were too many hotspots and the mix was very thick. I'm letting this dry but wondering if the synth will be unsuccessful because of the temperature jump, or is that only a problem if it happens during the erythritol addition?

Thanks

mnick12 - 12-7-2010 at 17:32

There are already quite a few threads on ETN, use the search engine.

If your having a problem with your etn's crystaline properties you can do a real easy crystalization from OTC things, Acetone a glass jar and a heat source. Simply dissolve as much of your crude ETN in warm acetone as you can then evaporate a small amount of the acetone, and place it in the freezer your ETN should crystalize out.

Also if your having problems with chunky nitrations try nitric acid or if you can not get any try ammonium nitrate.

jack3k3 - 12-7-2010 at 21:29

Yes I've done some searching but was not able to find too many specifics on how to actually perform the crystallization. Unfortunately I had an extremely bad accident upon trying the acetone crystallization, some poorly made glassware shattered upon heating (most likely using too hot of flame) and acetone was ignited but as I had prepared a safe area it was able to burn out without harm. I think its time to invest in some lab quality equipment. :o

mnick12 - 12-7-2010 at 21:36

Uhhhh thats a little scary, ETN is rather sensitive stuff. Just something to note never use an open flame with flammable solvents that HE's dissolved in them. I was thinking using a hot water bath to warm your acetone. Hotplates are pretty cheap at wallmart I got a 1kw plate for under $20.

jack3k3 - 12-7-2010 at 21:45

Yes indeed a hotplate will be on my list, note that the heating was just to warm it up, I wouldn't add further risk by adding ETN to the mixture while heating over flame. Either way this is one of those cases where a good lesson is learned to always take precautions and use the correct equipment or risk disaster! Hopefully others will learn from my mistakes.

Also another note about the ETN synth I detailed in the second part of my post, despite the heating of the kno3+sulfuric mixture, it seems nitration was still successfull as I tested a piece of the precipitate with the hammer test and it did detonate, albeit not how I would hope. Probably will improve a bit with recrystallization. I will keep things updated.

jack3k3 - 13-7-2010 at 20:25

Today I was able to get a hot plate and heat up the acetone and stir in the ETN. After sufficiently dissolved in about 300ml I allowed to cool then placed in an ice bath. I let it sit for about 2 hours and filtered out the precipitate but it was VERY little compared to the amount I put in. I do not know the weights but I can say I put in something around 30-50ml of substance and only got out maybe less than 2ml. So I figured I didn't allow enough time for it to crystallize and I'm allowing the solution to sit overnight. Would this amount of time seem like enough or should waiting over night do it?

Thanks.

mnick12 - 13-7-2010 at 20:37

How much ETN did you have? 300ml sounds like way to much acetone. Also cooling to rt is not usually good enough to get full crystalization, you should have waited for it to cool to rt then pop it in the freezer for a few hrs.

jack3k3 - 13-7-2010 at 20:50

Well I did an ETN yield with 35g erythritol so my yield should have been around 50g or so ETN. And I actually had about 250ml acetone now that I checked.

Also, I allowed it to cool to RT but then I placed it in an ICE bath for 2 hours then filtered. Currently its in the ice bath again but I could place it in the freezer if necessary.

Melgar - 13-7-2010 at 23:47

Acetone will dissolve a surprising amount of ETN. Also, the key to detonating it in the presence of aluminum is rapid heating; if there is too much of it, you won't be able to heat it quick enough.

quicksilver - 14-7-2010 at 05:36

Acetone is much too strong a solvent for ETN. The standard is to use anhydrous ethanol or methanol to re-crystallize. The best method for the cleanest crystal shapes, etc is to use an alcohol.

jack3k3 - 14-7-2010 at 16:52

Quote: Originally posted by quicksilver  
Acetone is much too strong a solvent for ETN. The standard is to use anhydrous ethanol or methanol to re-crystallize. The best method for the cleanest crystal shapes, etc is to use an alcohol.


So I've read but I've also seen people saying acetone works, just no so well. My question then is, what does too strong really mean? Can it destroy the ETN or not allow as much to crystallize out as an alcohol can?

Also, as I will probably try to obtain some methanol, would the car product Heet work? From what I've read its something like 97% methanol and comes in 12oz bottles for 2USD.

mnick12 - 14-7-2010 at 19:01

No acetone wont destroy etn, but it will dissolve a large amount of it. When preforming a recrystallization you want a solvent that will dissolve your desired product at a higher tempurature, so that when you cool it the pure crystals form. Here is a usefull vid that should help you understand http://www.youtube.com/watch?v=7LBGQHjgHEw . Good luck

jack3k3 - 14-7-2010 at 19:07

Well luckily after allowing it to sit in the freezer a couple hours I was able to get a much better quantity out. Now I think there may be some still left so I'm letting the acetone evaporate off and I'll get the remaining (though its probably not as good quality).

I tested the purified product and it performed quite nicely with the hammer test. I'm currently sourcing some 30% h2o2, in the mean time could a small det cap be built out of 1/4inch copper tubing with either coffee ground al/etn mix or black powder primary? I have had 50% success rate on al foil wrapped etn, surrounded by a blackpowder mix surrounded by another al foil. Not sure though if either could be reliable at all.

[Edited on 15-7-2010 by jack3k3]

Melgar - 14-7-2010 at 20:37

Try mixing a strong dry oxidizer like potassium permanganate with the aluminum. Or use a bit of thermite with a little extra aluminum instead of straight aluminum. That should expose the ETN to both rapid heating and aluminum metal. Be careful with Al/KMnO4 mixtures though, I've used them without incident but I hear they can be unstable.

jack3k3 - 14-7-2010 at 21:39

Hmm, I'd like to try that but unfortunately I have no access to those things. I get paid tomorrow, which means I will be able to buy h2o2, aluminum powder if I can find it, and some proper glassware/hotplate.

quicksilver - 15-7-2010 at 05:20

Using standard industrial acetone leaves hydrocarbons in the crystals making then soft (& compromised with foreign matter) so that impact testing will not reflect the actual sensitivity. Generally re-crystallization with standard industrial acetone is not done with ETN and several other esters. Store bought acetone is too impure and simply not the correct materiel. It's only recognized when a comparison's finally made side by side with a quality alcohol.

the Z man - 15-7-2010 at 06:09

If you can get Mg pencil sharpeners you can try to mix ETN with some Mg fillings and ignite it with Mg/KNO3 flash slightly pressed on top. When I tried less than a gram in paper tube it kinda worked but the MHN (I used MHN instead of ETN) went low order (?), but I think that with better confinement (such as your copper tubing) it can go high order.

quicksilver - 15-7-2010 at 10:58

....Not exactly sure what you mean (?) The concept is to determine if the material has impact sensitivity that would be similar to most any energetic w/ similar predilections.
If somewhere at the level of 50mg receives impact on a hardened surface with another hardened weighted object, ETN will detonate. The concept is to see the detonation threshold through impact sensitivity. Unlike NC, I don't believe that the nitrated polyols can explode in a definably lower level. They either go or don't.
I take it that you mean the material deflagrated??? If not and it DID make a "pop" then it exploded and most likely had a velocity faster than the speed of sound. The confusing element for some is that substantially small samples of materials will make a appropriately smaller detonation. This continues until there are some materials that can detonate properly from a single crystal being stimulated. The fascinating thing is that at that point the detonation is so small that the level of surrounding air moved almost ceases to make a sound! This can be seen very clearly in many primary explosives that yield single crystal synthesis safely (the azides typically do NOT yield this property due to safety issues).
ETN however, should detonate well into milligram level amounts IF the crystals are well defined & impact or electrical stimulation are implemented properly.
Heat or flame stimulation of ETN must be made with corresponding speed or the melting/burning effect will overlap the potential for detonation. Retaining the material in an enclosure may help but generally these are secondary explosive and as such they cannot detonate without appropriate stimulation.
Impact in some unique mechanics simulates the ignition of adjacent secondary (explosive) materiel. Simple application of heat would not have the same effect as that of a primary explosive: the stimulation you are attempting to recreate is very sudden, deeply sub-second stimulation. This is not an easy thing to do.


EDIT:
It's within possibility to have "flash heat" significant enough to stimulate secondary explosives reducing the DDT to milliseconds or faster. However the need for focused application would be more toward the level of an "exploding bridge-wire" than direct application of flame. Conceptually, you would need to have something substantially different than flash powder or similar to make this occur. An electric discharge of an old fashioned flash bulb with zirconium wire wool MAY be at a level appropriate to yield detonation in certain materials.




[Edited on 16-7-2010 by quicksilver]

the Z man - 15-7-2010 at 17:18

I try to clarify:
I was trying to initiate MHN by flash heating and I thought some Mg in it would help maybe enhancing sensitivity to heat or making MHN act like an oxdizer or so. So I manually pressed this mixture (about half gram MHN with very little Mg) in a drinking straw (I forgot this before) and pressed about .1-.3 flash on top of it. I pressed it as the FP was not meant to initiate as a primary by shock, but by heat shock and I thought that pressing it could slower the deflagration so that the MHN/Mg was exposed to the intense heat for a longer time. Then the plastic straw was tightly wrapped in paper to enhance confinement. Unfortunately that day I had to test it in a very small space so I could stay at most at 4 meters from the charge and as I was afraid of some kind of debris from the groud blinding me I was turned to the opposite direction, and I can't describe you the way the explosion looked like. But I can tell that from the sound of the explosion it seemed to me that was much more than only the FP. I say that it went low order because although upon accurate inspection no MHN was found the straw was found broken in very big chunks just like a fireckracker, that is impossible with an high brisance HE like MHN, unless it went low order.
PS. sorry for the english here it is very late night and I'm very tired.

jack3k3 - 15-7-2010 at 18:08

Well, I gathered some new materials (heet for methanol, 27% h2o2 for AP) though I did leave out that acetone solution and I actually left it on top of a sheet of al foil. When I came home I found the foil had been eaten away with some tiny holes in it and when i lifted it in sheared into straight pieces. I had quite a bit of crystallized precipitate (yellow in color, also mixed with paper towel fragments from a pour filtering). I tested a bit of the al foil that had crystal stuck on it and it detonated.. I was under the assumption acetone only dissolved plastic... does ETN dissolve al or have some reaction with it like others have said ?

quicksilver - 16-7-2010 at 04:14

Your H2O2 was more that likely the culprit for the Al foil being eaten away. 27% is pretty strong; strong enough to pop some holes

jack3k3 - 16-7-2010 at 06:01

Actually sorry I wasn't clear, the acetone solution sitting on the al foil was actually the previous attempt at ETN re-crystallization, so it was acetone with ETN dissolved in it, no h2o2 was present.

hissingnoise - 16-7-2010 at 06:41

Some foils are plastic-coated thin Al films - when the coating is removed the fragile thin metal film disintegrates, more or less. . .

quicksilver - 16-7-2010 at 07:55

Makes sense. I can't think of a reason for it to get eaten aside from a idiosyncratic thing like that. But again it could be acid. You report a "yellowing"....Often when acid is active within many materials a yellow coloring is visible until further re-crystallization (occasionally more than one re-crystallization!).
ETN crystallizes in platelets, which can retain both moisture and acid easier than certain other structures. MHN however forms needles which have somewhat similar issues as platelets and certainly don't compact as easily. Quality MHN will always display needles as does nitroguanadine. It's one of the ways you can tell if you hit the "hex" level of nitration in mannitol.....
The reason why impact testing is important is that since you deal with an essentially flat crystal, when it is dry & cleanly formed, it will have a more sensitive response to impact. It basically tells you if most aspects of the synthesis are appropriate. Sluggish response, heavier blows, more material needed to detonate, indicate possibly that something is amiss.



EDIT:
This is also well used in Picric Acid.
Well synthesized Picric Acid (all of it being TRI-Nitrated with little to NO lower nitrations present) will pop off a clean detonation via impact with as little as 100mg under steel to steel.
Picric Acid that does NOT detonate with impact stimulation has either too many lower nitrates present or has substantial moisture within the crystal lattice.



[Edited on 16-7-2010 by quicksilver]

jack3k3 - 17-7-2010 at 01:21

Alright so I had a successful (I believe) test finally. I used 1/4inch copper tubing, crimped one end, filled about 4inches (quite a bit yes) with ETN and slightly packed (albeit not much as my packing tool was much smaller than the tube inner diameter), then filled 1/2inch with AP and fuse inserted, copper carefully crimped around fuse. Detonation took place in a safe empty lake bed and observed from cover far away.

Explosion was fairly loud, however not what I would have expected, I suppose its possible only the AP detonated however I can not tell for sure as I can not find the copper tubing, so it's also possible it was completely destroyed.

Either way, is this method a good idea? I have done many searches on google for improvised det caps/ blasting caps but haven't found much info besides a brief doc on using copper tubing.

the Z man - 17-7-2010 at 03:21

Don't crimp the detonator tube around the fuse, especially when you're using something like AP. Also organic peroxides become very unstable when in contact with some metals, especially copper. You had better use something like aluminium tube or a plastic tube or even a drinking straw. Always use as little AP as you can (with ETN you need very little AP) and push it down VERY gently, and while you do this don't keep it in your hands. The fuse should be sticked with something like electrical tape taking care that tape covers the open side of the tube, so that sparks from the fuse cannot reach the AP. After AP has been added handle the detonator as little as possible.

quicksilver - 17-7-2010 at 04:55

I would be extremely careful with metal contacting an energetic peroxide.......
The only studies done of energetic peroxides was via the USBoM with HMTP and the major reason why they stopped was that Bakelite tubes were the only material (polymer plastics were not popular at that item; many had not been invented) that could be used with safety and the material had an even lower shelf life than Hg Fulminate. TATP is actually a much less efficient initiator than HMTP. The later also dries fairly well thus making it much more stable than TATP. The inconsistent results of TATP have been too many to quantify & is generally considered to be a setup for problems.

jack3k3 - 17-7-2010 at 09:39

Quote: Originally posted by the Z man  
Don't crimp the detonator tube around the fuse, especially when you're using something like AP. Also organic peroxides become very unstable when in contact with some metals, especially copper. You had better use something like aluminium tube or a plastic tube or even a drinking straw. Always use as little AP as you can (with ETN you need very little AP) and push it down VERY gently, and while you do this don't keep it in your hands. The fuse should be sticked with something like electrical tape taking care that tape covers the open side of the tube, so that sparks from the fuse cannot reach the AP. After AP has been added handle the detonator as little as possible.


I tried to accont for some of these things but you are right its still risky.

For example, primary packed immediately prior to detonation, plenty of room was left between area that was very carefully crimped and the top of the AP (also it was ensured that no ap was in the area). Also fuse was quite long to ensure no sparks jumped to AP.