Newsgroups: rec.pyrotechnics
From: ahahma@utu.fi (Arno Hahma)
Subject: Re: nitroglycerine
Organization: University of Turku
Date: Sun, 13 Nov 1994 20:28:37 GMT

In article <3a3gbk$425@sparc.eunet.si>,
Grega Klemenc <eul0125@sparc.eunet.si> wrote:

>Yesterday I made nitroglycerine. I used concentrated nitric and suplhuric 
>acid and pure glycerine. The stuff burns well, but won't explode. What's 
>wrong ???

Nothing is wrong. Pure NGl does not explode on ignition, it merely
burns with a nearly invisible, yellowish flame, just like smokeless
powder. This applies to small amount (up to a spoonful or so).

However, if it is heated gently up to 200 oC or more and under the
slightest confinement, it will detonate suddenly. I managed to detonate
a beaker in my hand that way and almost kill my brother to laughter
;-). No injuries of any kind, but I guess I have never been so scared,
not before nor after that event. And my brother has never laughed as
well before nor after. It was a classical, old fashioned lab accident
that one can't believe to become true. All that was missing was a black
face - fortunately, NGl burns clean ;>.

Also, NGl will detonate, if hit under confinement - droplets or liquid
will hardly detonate from a hammer blow unless it is in a tight
container.

NGl is pretty hazardous material, especially in large amounts (large =
more than a few ten grams). In large amounts, ignition will lead to
detonation, if not immediately then after a delay of some sort, the
more material the higher the probability.  Also, dropping a bottle can
cause detonation (confinement and impact), again, probability scales
with amount.

NGl is not stable in storage, unless stabilized with akardites or
centralites or equivalent stabilizers. Old NGl (like one year) may
explode by itself in storage, unless stabilized.  Again, the larger the
amount the larger the probability.



ArNO 
    2

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: sci.chem
Subject: Re: Nitroglycerine (medicine), storage & handling
Date: 4 Jan 1996 02:36:16 GMT

In article <30eafa3b.0@news.cybernet.dk>, kurir@cybernet.dk (Nancy
Andersen) says:

>Do anyone have experince with handling and storage of nitroglycerine
>for medical use?
>
>Nitroglycerine for medical use is dissolved in ethanol, and is
>harmless until spill occur and ethanol evaporates (my idea!). Does
>anybody have any experince, and if so what to do if spill occurs.

If the spill is on a non-porous surface, use a large excess of 
sawdust to soak up the liquid and later burn the mixture in
the open in a thin layer and remotely.

If the spill is on a porous surface, repeated treatment with an
18% sodium sulfide (Na2S:9H2O) will destroy the NG.

Jerry (Ico)

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: rec.pyrotechnics
Subject: Re: nitroglycerin question
Date: 24 Jan 1996 23:20:22 GMT

In article <4e66mf$jk9@news1.usa.pipeline.com>,
ricin@usa.pipeline.com(David Halpern) says:
 
>          I am doing a report in chemistry class about nitroglycerin. I
>have all the information I need on it EXCEPT how sensitive it is. I have no
>other place to turn to.  I am finding many inconsistencies on this. For
>example, Encyclopedia Britannica states in its micropedia that freezing it
>makes it more sensitive while its macropedia says it makes it less
>sensitive. All of my schools chemical references only say that it is
>extremely sensitive which tells me nothing. If anyone can tell me how many
>dynes, newtons, etc. or just give me an idea of what it takes to set it off
>would be greatly appreciated.  
 
30 kg-cm on the Bureau of Mines apparatus (2kg weight)

1 inch-pound on the Picattiny Arsenal apparatus (1 lb weight)

The difference lies in the geometry of the samples, but in
either case, these are low values compared to most explosives,
and they give you a good idea what not to drop on a sample.

Jerry (ico)

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: rec.pyrotechnics
Subject: Re: nitroglycerin question
Date: 27 Jan 1996 07:17:21 GMT

In article <Pine.Sola.3.91.960126175858.8513A-100000@ux4.cso.uiuc.edu>,
brown michael david <mdbrown2@ux4.cso.uiuc.edu> says:

>On Fri, 26 Jan 1996, Gary M. Watson wrote:
>
>>In article <Pine.Sola.3.91.960126163841.23063D-100000@ux4.cso.uiuc.edu>
>>brown michael david <mdbrown2@ux4.cso.uiuc.edu> writes:
>>>On Fri, 26 Jan 1996, Morne K. wrote:
>>>
>>>Big old *SNIP*
>>>>About the freezing part; when you freeze nitroglycerin it becomes less 
>>>>sensitive but, and now comes the tricky part ,when you try to defrost it
>>>>it is almost bount to explode.
>>>
>>>Now who told you that? You sound a lot like Toe Jamm (or was that Dr 
>>>Jamm) making stuff up for story-time. I do that a lot with my kids, but 
>>>how are they to know those scars didn't come from a big scary monster?
>>
>>He may be right in this case.  I have read somwhere that the transition
>>to or from the frozen state is dangerous - it seems to me it had something
>>to do with the pressures as it expands in a container while semi-crystilline.
>>Maybe Ico has more data handy.
> 
>Not to split hairs, Gary, but he did say that the tricky part is when you 
>defrost it. The container would have expanded upon freezing and would 
>already have been deformed when the defrosting (as he puts it) begins. I 
>do agree that there are others, especially Ico, that are more qualified 
>to answer.

As you guys probably know, NG has two distinct freezing points,
at about 13 (stable) and 2 degC (labile). As far as I am aware,
the material does not expand on freezing but contracts about
8 percent. In a laboratory, NG can be repeatedly frozen and
rethawed without any problem.

There is a problem with NG dynamites which have been frozen
exploding on thawing. I don't believe that these explosions 
are a consequence of the expansion of the new liquid phase
so much as of simple cracking of the charge or of the NG
crystals brought on by uneven temperatures and the resultant
stresses. It's not easy to melt glass without cracking it
unless you are careful to heat it evenly.

It is no surprise that cracking could act to initiate the
NG, especially if it occurred in the presence of liquid
NG, which is more sensitive and more prone to LVD (low 
velocity detonation). I once worked with a material which 
always detonated on contact with glass breaking in tension. 
Whenever I'd snap a glass capillary tube of the volatile 
material in a stream of nitrogen for COH analysis, the stuff 
would sting my fingers through the latex tubing. One day a 
Raman tube holding 10 g broke under hydrostatic pressure ... 
but that is another story for another day.

There is an interesting question about whether or not the
tricky situation of two possible solid phases plays any role 
in the NG thaw-and-shoot problem.

As you know, dynamite manufacturers use a mixture of NG and
ethylene glycol dinitrate so that the two compounds act as 
mutual antifreezes.

Another side issue of this topic was the report long ago of
"memory" in melted NG which had recently been rethawed. It 
was said that if the freshly melted material is refrozen,
it will revert to whichever phase it was in before it was
thawed. Shades of catalyzed water ???? Probably not. The
experiments led to some early speculation that liquid NG
may have two distinct isomeric forms. Perhaps someone in
the sci.chem forum may have later information on this topic.
Modern spectrophotometry should by now have made child's
play out of this question.

I guess I learned what little I know too far away and too 
long ago.

Jerry (Ico) 

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: alt.engr.explosives
Subject: Re: Gunpowder and grease
Date: 20 Jan 1996 05:08:45 GMT

In article <RGTYMOWS.92.00136338@BIOLOGY.watstar.uwaterloo.ca>,
RGTYMOWS@BIOLOGY.watstar.uwaterloo.ca (R. Tymowski) says:

>Late last night, I stumbled onto a war documentary in which it was mentioned 
>that during WW2, old cooking grease was collected and used in the production 
>of gunpowder. (I'm assuming that "gunpowder" refers to "black powder"). 
>Anyway, what exactly was it used for? The only thing I can think of is in
>moisture-proofing the contaiers in which the BP was stored. But then why not 
>use mineral greases and tars, which would deteriorate much less rapidly?
>
>I know that a century or two ago, bullets were lubricated with animal fat (I 
>believe that this caused some major problems for the British in India). Even 
>though I thought that by the middle of the 20th century some better 
>materials would have been substituted, maybe that's what was being referred 
>to. 
> 
>Could someone shed some light into this? 

Others may know, but I can speculate. During the war we were told
that the grease we turned in was used to manufacture soap, which
was in noticeably short supply. The saponification of animal
or vegetable fat yields metal soaps AND glycerine. In times of war, 
the usual palm oil and coconut oild would be in short supply so it 
is possible that the glycerine from our bacon grease wound up as 
nitroglycerine in double base smokeless powder. 

Glycerine had been be made by an older fermentation reaction and
from propylene a cracking process shortly prior to WWII, but it 
is unlikely that the latter method was widely enough established 
to meet wartime demands.

Jerry (Ico)

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: alt.engr.explosives
Subject: Re: PETN and Propelyene Glycol Dinitrate  (PGDN)
Date: 31 Oct 1996 02:07:04 GMT

In article <32784BDD.3D3A@tick.toc>, DooDaa <DooDaa@tick.toc> says:

>Hello there, 
>I'm new to this group and am whether anyone has made a mixture of PETN
>and PGDN (80/20), like PETN/Nitroglycerine ?  I know that the latter
>mixture does exist, but I am hesitant to make NG 'cause of it's
>sensitivity etc.  (And PGDN is more powerful... :) )
>Any one?

Uno momento.  Ethylene glycol dinitrate is properly oxygen balanced and
therefore very potent.  Nitroglygerine is a tad oxygen rich and 
propylene glycol dinitrate would be somewhat fuel rich.

Why would anyone want to make a mixture of any of these things with PETN?
I am asking what property such a mixture would have that either straight
PETN or NG does not already have other than being a slushiness.

Jerry (Ico)

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: alt.engr.explosives
Subject: Re: PETN and Propelyene Glycol Dinitrate  (PGDN)
Date: 31 Oct 1996 21:16:56 GMT

In article <32798AA9.6A26@tick.toc>, DooDaa <DooDaa@tick.toc> says:

>Thanks for the civilised reply (My first one so far) !
>
>According to an explosives book, adding PETN and NG makes a "more
>powerful compressible explosive than any other hitherto known.  It is
>more powerful than Pentaerythritol Tetranitrate alone, evolving 1450 cal
>per 1 kg, compared to 1403 cal per 1 kg for PETN alone."  It is also
>more dense than just PETN powder (spec. grav. 1.2), meaning that you
>won't have dust everywhere when you try and make a device.  They also
>say it have better perforating power.
>
>Regards
>DD.

DD, you should take the information you quoted with a grain of salt.
It is true that there is a small gain in energy output because of the
synergism between the slightly oxygen-rich NG and the slightly oxygen-
poor PETN, but the minor difference in energy (ca. 50 cal/g) is much 
too insignificant to warrant the increased hazards associated with
NG.

If, indeed, PETN had a specific gravity of only 1.2 then one might notice
the difference when it was mixed with the denser NG.   However, the
crystal density of PETN is actually 1.77, which is significantly greater
than that of NG.

Based on your 1.2 specific density quote, I suggest that your author
meant to say that one could use NG to fill the interstices in uncompacted
PETN powder.  This would allow one to fill a piece of ordnance using 
a slurry of the two where compaction was not feasible.  This technique
would provide a powerful charge, but in a metal casing you could expect
the NG to shoot by LVD mechanism (read cavitation) if it took a sharp
rap by a hammer or the like.

In the real military, this kind of situation is handled by using melted
TNT rather than NG to form Pentolite or, better yet, cyclotol (from RDX).
The solidified mixture is way less dangerous than the corresponding NG
mix and not much less powerful.  If they want more power, they just add
aluminum to form H-6.

Jerry (Ico)

From: ahahma@kontu.utu.fi
Newsgroups: rec.pyrotechnics
Subject: Re: Nitroglycerine/HNO3
Message-ID: <1991Apr15.230726.38164@kontu.utu.fi>
Date: 15 Apr 91 23:07:26 GMT

In article <1991Apr12.175115.3415@waikato.ac.nz>, chem2149@waikato.ac.nz writes:

>>> First, using nitric acid alone won't make NG. Secondly, off-the-shelf

Yes it will, as long as the acid is more than 70 % and you use an excess of
it. Using too little and too dilute acid will yield glyceryl mono- and
dinitrates, that are not as explosive as the trinitrate. These lower nitrates
are more unstable than the trinitrate and may cause a fume-off reaction.

You are right about the usual nitric acid (65 %), it can be used with
suplhuric acid, with a yield of over 95 %.

>>> acid with dissolved NO2 - it will rip the glycerine molecule to shreds,
>>> not mate with it.

Right. Any nitrites must be removed. This is best done by adding urea to
the mixed acid as long as it is still warm after mixing. The urea
will destroy any nitrites present and the acid can be used as it has
cooled down.

>> pharmacy) is only 70%.  If you use this with 100% sulfuric
>> you will not be able to nitrate glycerine (I tried once).

Yes you can, it is used even industrially with very good yields.

>> find in a well equipped chem. lab. and is best made yourself
>> as Oz said by distilling KNO3 with sulfuric acid.

Or better, with a continuous distillation process using sulphuric or
phosphoric acid to break the azeotrope. The water binding acid can
be concentrated and recirculated to the process. I have made this
successfully and the product was very pure, colorless, 99,8+ % nitric
acid.

>> yard on his picnic table.  It produced a lot of brown smoke and in
>> a violent reaction spewed acids all over the table.   After that he
>> decided not to persue it any further.

That is a typical cook-off reaction - I have managed to do that
with spent mixed acid, too. (I.e. the nitrated products had
been mostly isolated, but the remaining traces caused a vigorous
reaction and a cloud of NO2). The temperature may never rise above
20 C during the glycerine nitration. If it rises to 30 degrees, the reaction is
just about to go out of control.

>> I would also recommend cyclonite instead of nitroglycerine.
>> You also need 100% nitric acid to make that, but it can
>> be safely done.

Yes, I do agree. Moreover, the process is more effective and easier
to carry out. You have little problems with the cooling, since the
temperature is rather high for a nitration; 63 to 68 oC with the
KA-method using acetic anhydride, hexamine nitrate, ammonium
nitrate and nitric acid.

>> Note that nitration of glycerine and cotton is a condensation
>> reaction and should not produce NO2, unless oxidation is occuring.
>> Nitration of aromatics and in the production of cyclonite does
>> normally produce NO2.

Nitration of something should not produce any nitrous fumes. If such fumes
develop, there is some oxidation going on. You are right about the
aromatics, they often require high temperatures thus causing some
oxidation to occur. Another exception is the nitration of dimethylaniline -
one of the methyl groups is oxidized by the nitric acid releasing lots of
NO2 - in this case the fumes are "normal". In the production of hexogen
absolutely no fumes are formed, unless you are using the oldest, direct
nitration method. Other methods are "clean", some do not even need nitric
acid at all.

> As a chem major (almost PhD) all the above statements by Steve are correct.

Almost all of them.

> I would add that white fuming is considered 100% HNO3 and that red fuming is
> said to have dissolved NO2 which would make nitrations very dangerous.
> Never seen red fuming yet, early rocket fuel oxidizer.

You are right, this should be made clear.

100 % nitric acid is called
WFNA (White Fuming Nitric Acid), since it is a totally colorless, strongly
fuming liquid. This is the grade used in nitrations. If you get some
nitric acid (100 %) off the shelf, it will never be WFNA. If nitric
acid is kept a few days, it decomposes and finally, it is turned into
diluted RFNA (about 80 % HNO3, 10 % H2O and the rest oxides of nitrogen).
This is why strong nitric acid has to be made and used at once.

RFNA (Red Fuming Nitric Acid) is anhydrous, (i.e.
seldom contains water more than a few per cent) too. In addition to
nitric acid it contains up to 25 % various lower oxides of nitrogen
dissolved, mainly NO2. These make the acid light yellow to deep red in
color. This acid fumes even more stronly than WFNA and is more corrosive
at least to organic materials, like hands ;-). RFNA is very dangerous
mixed with anything combustible. Such mixtures are often (this is a
rule better than an exception) hypergolic, i.e. they ignite on contact or
after a short delay. Only the most stabilized aromatic compounds (like
nitrobenzene) are stable dissolved into RFNA - these mixtures are
extremely powerful explosives, very brisant and high in energy content.
Attempting a nitration with RFNA will cause trouble, an explosion
in the worst case or at least a cook-off reaction.

> I have never made NG but have made PETN, RDX, Pb(N3)2, cellulose nitrate,
> worked with NG, picric acid, TNT etc.

I started BIG, and I am still alive... Sometimes you are lucky in the
course of evolution....

> MARTIN VAN TIEL

                              R'
                                \
                                 /======\
                               /          \        O
                             /     ArNO     \    //
                             \\        2    //--N+
                              \\          //     \
                                \\------//         O-
                               /
                             R

From: ahahma@polaris.utu.fi (Arno Hahma)
Newsgroups: rec.pyrotechnics
Subject: Re: Nitroglycerin
Message-ID: <1992Feb11.164953.17738@polaris.utu.fi>
Date: 11 Feb 92 16:49:53 GMT

In article <AdZjpMW00WcDI_aGAN@andrew.cmu.edu> mf3s+@andrew.cmu.edu
(Martin David Frankel) writes:

>> >Notes:
>> >Store nitro in fridge or freezer.

Well, that is ok, but thawing it is not. Better keep it frozen from
then on.

>I second that.  The mere act of freezing nitroglycerine is entirely
>sufficient to detonate it.

Not the freezing, but melting it is certainly most dangerous.
Nitroglycerine, especially frozen, is unpredictable, sometimes it
fails to ignite with a detonator, sometimes it blows up when looked
upon.

>However, I don't know what its freezing point is... possibly colder than
>most common houshold freezers.

It is around +13 oC. Possibly warmer than the common household fridges.

>Nonetheless, I wouldn't want to take any chances... use the fridge, not
>the freezer.

Use none of them. If you absolutely have to store the nitroglycerine,
dissolve it into acetone or ether (they are miscible). 2/3 or more
solvent and the rest nitroglycerine. When you need the nitro, simply
let the solvent evaporate at room temperature (important, I have
learned to point this out ;-) or pour the acetone solution into cold
water (nitroglycerine precipitates). Storing, handling and
transporting nitro this way is safe, as long as the solvent percentage
does not drop too low.

>	-- Martin

ArNO
    2