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Author: Subject: Picric acid sensitivity
vulture
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[*] posted on 1-1-2010 at 02:34


Interesting this comes up now. In our university lab I found an old bottle of about 50g of picric acid. It clearly showed signs of sublimation inside the lid and was bone dry. Estimated age was more than 30 years, given the total absence of any safety information and general style of the label.

It was carted off in a large plastic drum with PS filler and handed over to EOD. They didn't detonate it on the spot but took it with them. It was all quite relaxed, no evacuations or anything.

[Edited on 1-1-2010 by vulture]




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Rosco Bodine
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[*] posted on 1-1-2010 at 03:30


Compliments to you and your colleagues for appropriate discretion in keeping things low key. The hazard truly is minimal to non-existent anyway, and hysteria freaks out the public which consequentially brings undeserved scrutiny and regulation to scientists who already have too much red tape. I use storage bottles which have polypropylene caps bearing a non rotating 2mm thick solid teflon disc that deforms against the rim of the bottle like a wax. Also I have more expensive reagent bottles which have the entire threaded cap made of solid teflon. I have a half dozen solid PFA 2 liter storage cannisters which have a silicone backed solid teflon disc for added resiliency at the seal. The instruments and equipment which I have managed to collect over the years is largely government surplus. There are probably a few of us who have accumulated a fair amount of expensive equipment over the years and who consider it to be valuable personal property worth protecting from those who for whatever reason would attempt to violate our right to retain ownership and use of what is our personal property.
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[*] posted on 1-1-2010 at 04:29


I must admit that I was afraid of opening the bottle, given the large amounts of crystals inside the lid. Also, you are probably familiar with the old Aldrich brown glass bottles, they often had a plastic cap with metal inserts or even metal threads.

The bottle was labeled as microscopy coloring reagent with no immediate reference to its contents. Only closer inspection revealed a formula which contained a most peculiar ratio of N and O. :D

Last but not least, we shouldn't forget that the acute toxicity of picric acid is something which shouldn't be drowned by the discussion about the severity of the explosion hazard.

BTW, Belgian EOD probably has plenty of experience with degraded TNP and derivatives. They are still called in regularly to clean up WWI duds from the battles around Passendale. This usually amounts to TNP of questionable quality in metal casings which have been buried for about 90 years...

[Edited on 1-1-2010 by vulture]




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Rosco Bodine
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[*] posted on 1-1-2010 at 07:01


If you read about the history of picric acid and learn that for a hundred years chemists were working with the material as a stain and dyers were using it also,
without anyone discovering that the material could be used an explosive,
until it happened that someone investigated the possibility it could be initiated by a powerful enough primary explosive used as a detonator .......that alone will tell you that picric acid is not unduly sensitive. Because it is certain that during the
careless handling that occurred for a hundred years, that any doubt about its
nature as an explosive would have been very suddenly removed and its explosive nature revealed to some
unlucky soul, rather than for its explosive properties to quietly await the deliberate pursuit of someone intentionally causing it to detonate.

At this point I reiterate what I have said before about the misleading hazard misinformation which has been published by regulators being 100% propaganda , as the information is completely false. Whether the reason is hysteria or political or some mixture I don't know and will leave that mystery to others.

There was some prior discussion in this thread about who owed an apology to whom.

Let those who make false representations and insults to deceive make their apologies.

The truth and verifiable information is what you have gotten from me.

Trust in the LORD, ( but keep your powder dry )

[Edited on 1-1-2010 by Rosco Bodine]
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[*] posted on 1-1-2010 at 19:52



The following is a compendium of information from various sources such as
The Chemistry of Powder and Explosives by Tenney
and these two standard military texts.
Military Explosives TM-9-1910 from 1955
Picric acid munitons are obsolete and so it is omitted in the later edition
from 1984 - Military Explosives TM 9-1300-214
* Note
An authoritative material safety data sheet would be the military
HCSDS - Hazardous Component Safety Data Sheet
- 00905 - Ammonium Picrate
There must be one for Picric acid itself. These are not generally
available outside of authorized channels of use.


A little bit of history worth repeating.

_

1771 - Picric acid was first prepared by French chemist Pierre Woulfe,
who found that the action of Nitric acid on Indigo yielded a material
which dyed silk yellow. http://en.wikipedia.org/wiki/Indigo_dye
- Picric acid is an aromatic nitro compound which is used as a yellow dye
in the textile industry.
For a century thereafter the compound was used without recognition
that it was capable of being made to explode.

1778 - Hausmann isolated the substance and reported further studies
of it in 1788

1800 - Mercury Fulminate was discovered by English chemist Edward Howard
who described its detonating properties in a paper before the Royal Society.
- This was to prove crucial for the eventual use of Picric acid as an explosive.

1807 - The principle of using Mercury Fulminate as a primer was patented
by Rev. Alexander J. Forsyth of Aberdeenshire, Scotland.

1841 - Ammonium Picrate was first prepared by Marchand, unaware of the
explosive properties which would not see use until decades later.
- Ammonium Picrate is distinctly less sensitive to impact than TNT
( 17 inches 2 Kg impact test ) and is unaffected by the steel shoe in the
pendulum friction test. In the sand test, Ammonium Picrate is not detonated
completely by either Lead Azide or Mercury Fulminate. A booster charge of
of Tetryl is required for complete detonation.

1843 - A. Laurent obtained Picric acid by the nitration of Phenol and also
found that some of the salts are explosive.

1847 - Nitroglycerin, an ester of glycerin and Nitric acid, was invented by
Italian chemist Asconio Sobrero. Because Nitroglycerin is sensitive to shocks,
commercial use was delayed until the invention of dynamite and blasting
gelatin.

1863 - Trinitrotoluene TNT was prepared by German scientist J. Willibrand.
Although TNT saw use for many years in the dye industry, TNT was not used
as an explosive until 1904.

1867 - The fulminate blasting cap, a device consisting of Mercury Fulminate
in a copper tube used to detonate explosives, was invented by Alfred Nobel.
This cap was crimped to one end of a safety fuse ( Bickford fuse ), and then
inserted into the dynamite.

1871 - The explosive properties of Picric acid are determined
by German chemist Hermann Sprengel
This became feasible only after the invention and general use of priming
detonating compounds ( Picric acid being a secondary explosive requires a
primary explosive to initiate it's detonation ). Picric acid is only slightly more
sensitive than TNT as indicted by 2 Kg impact tests , 14 inches for TNT
13 for Picric. But much more so by high velocity rifle bullet impact ,
only 2 % detonations for TNT 50 % detonations for Picric.
Temperature for explosion is less for Picric acid 322 ºC than TNT 475 ºC

1885 - 1888 - Eugene Turpin, a French scientist, patented the process
of melt-pouring picric acid into artillery shells as a high explosive filler.
Sprengel had discovered that Picric acid could be initiated by a powerful
detonator, but had not exploited this knowledge. The French Government
adopted a high explosive shell designed by Turpin using a Picric acid filler.
They designated the Picric acid filler as Melinite.

1888 - the British adopted Picric acid, which they called Lyddite as a
high explosive filler.

1900 - Picric acid ( British Lyddite ) shells were used in the Boer War but
did not detonate completely. This was attributed to faulty construction of
the detonators.

1901 - Dupre showed that picrates of Calcium , Lead ,and Zinc, formed
in situ by melted Picric acid initiates it's explosion.
- Moisture has a marked effect on reducing the sensitivity of Picric acid
to initiation. The presence of 0.5, to 2.0 % of moisture requires increasing
the minimum detonating charge. The drawback is moisture increases
Picric acid reactivity with metals such as lead, zinc, copper, nickel and iron.
Some of the compounds produced are very sensitive to heat , sensitizing
the ordnance to elevated temperatures. This reactivity requires that all
projectiles containing Picric acid have contact areas covered with acid
proof paint.
Metal Picrates formed by moisture retain water of hydration. Dehydrated ,
these Picrates become more sensitive to impact but are not as sensitive
as Lead Picrate which is more sensitive to impact than mercury fulminate
although it is less sensitive to friction.
Picrates of Lead and Zinc are formed in contact with molten Picric acid ,
which being primary explosives sensitive to heat explode at a lower
temperature initiating detonation of the Picric acid in the more sensitive
melted state.
It is believed this is the mechanism by which explosions from magazine
fires may have occured as the content of the shell melted and reacted
with lead / tin solder or galvanized steel forming picrates.
See Lead Picrate Page 6 of COPAE by Tenny

1909 - Ammonium picrate ( Dunnite or Explosive D ) was standardized in
the United States as a bursting charge for armor-piercing (AP) shells.
These AP projectiles could be fired through 12 inches of armor plate,
and could be detonated on the far side by an insensitive primer.
- The setback force experienced by a projectile at the moment of being
fired from a gun barrel is on the order of 20,000 times that of gravity.
A person subjected to such force a would become a puddle instantaneously.


In view of the foregoing it is incongruous how misinformation about Picric acid
continues to be asserted. The real risk from Picric acid in the dry state is from
inhalation of it's dust which is toxic. Another may perhaps be , that finely
powdered combustable materials are more readily ignited perhaps even in this
case by static electricity. The reason for maintaining it wet. The appearance
of large crystals is apprehended to be the formation of some salt as a result
of contamination since this is not the natural crystal form of Picric acid. It is
in all likelyhood simply the result of water evaporation producing slow crystal
growth on some particle which provides a point of nucleation.
If one comes upon a container labled baking soda one does not speculate
could it instead be Lye. So, viewing a container labeled Picric acid why should
one suppose it instead contains Lead Picrate.

What if speculations by safety professionals that one expects would know better
are entirely imagined supposititious scenarios. I am unaware of any account
or report documenting such occurrences as being actual.

.
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[*] posted on 2-1-2010 at 01:05


Well,

Someday, long time ago, a friend of mine had the oportunity of aquiring some 1 kilo amount of PA, from old reagent bottles. He had some bad experience detonating the homemade amounts (neither of the common peroxides could make it go off, but LA did the job with some strong confining). Consulting the literature revealed that it was actually quite difficult to make it kick back, even the army had lots of issues eventually phasing it out, so he didn't get the old PA anymore.

A documentary seen some time ago had also revealed the fact that burning picric acid is not that sensitive. In other words, in a certain fire incident, where an entire warehouse full of picric acid drums were burning and pieces of hot steel frame/plates from the roof kept falling in the blaze of burning melted PA, contrary to the authorities no huge explosion occured. Tonnes of PA just fiercely burned away.

If it was ammonium nitrate, an explosion would have been most certainly possible.

Having this said, in Rosco I believe.
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Rosco Bodine
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[*] posted on 2-1-2010 at 01:30


Yesssssss......yipppeeeeeeeeeeeeee !

Their eyes are open !

Thank you a_bab :D

It's really a hell of a thing to contemplate the implications .......I know,
believe me I know, and I really hope it isn't anything sinister Big Brother misinformation ministry kind of stuff,
but just bureaucratic stupidity working overtime. However, to be realistic,
when I see things like tobacco smoking out of doors being prohibited
allegedly due to the "risk" involving exposure of passersby to second hand smoke, it really makes me wonder how much overtime for bureaucratic stupidity
is enough. I wonder how much exposure to scrutiny a whole lot of regulations
could actually withstand, and how many of them are purely politics or only a
pretext for making impositions to tax and/or aggravate people.

BTW a_bab, or whatever your "real" name is .......... ;):P ....ha! just kidding :cool:

Interesting that the thread split has somewhat come full circle as now we see the matter revealed further about how regulators may be at odds with private citizens engaged in what should be their unimpeded private conduct. I have to wonder what Bethany Halford would think about this hopefully defused situation, where the "credentialed expert and giant of industry" would incite a mob of ignorant angry villagers to make their way by torchlight up the road to Dr. Frankensteins castle, to ransack his laboratory and put him in chains and throw him into prison.......for his daring to experiment with a dye that may also have other usefulness.

The irony and the parallel are colorful and rich.



[Edited on 2-1-2010 by Rosco Bodine]
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[*] posted on 12-2-2010 at 12:55


A Textbook of Organic Chemistry 1921
http://books.google.com/books/download/A_textbook_of_organic...

While not precisely true , that it is not an explosive itself , the cursory treatment
of this compound reflects the recognition at that time of it's insensitivity , while
noting the reactive nature of the material which is responsible for its undeserved
reputation.

Excerpt from TM-9-1300 Ammunition
http://www.everyspec.com/ARMY/TM+-+Tech+Manual/download.php?...

Acknowledges the shortcomings of both Picric acid and Ammonium Picrate with
regard to it's reactivity which promotes sensitivity. It can explode if heated confined
as inside a shell , otherwise it simply burns.

.


Picric.gif - 27kB Tm-9-1300.GIF - 22kB
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entropy51
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[*] posted on 12-2-2010 at 13:28


More evidence from the 1917 Chemical & Metallurgical Engineering, to raise Rosco's spirits a little higher.
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Rosco Bodine
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[*] posted on 12-2-2010 at 14:39


Sometimes folks can be slow to catch on .....and that's okay,
so long as they get there eventually, slow but sure works for me :cool:
(more often than I would care to admit actually) :D

http://www.youtube.com/watch?v=iOmb_U1k5Ys&fmt=18 How Long (before we get it right)

http://www.youtube.com/watch?v=kQMcZZURcwQ&fmt=18 Emerald Stardust

http://www.youtube.com/watch?v=o0vy4wDfrmQ&fmt=18 ditto

http://www.youtube.com/watch?v=7ZRSTNjVouM&fmt=18 Get Back To Serenity

[Edited on 13-2-2010 by Rosco Bodine]
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[*] posted on 13-2-2010 at 11:59


Hello,

Pure, properly looked after Picric acid is safe as a house. We all accept that. It's this unknown bottle of stuff containing 'Picric acid' that is presented to haz mat where all the fun starts, or stuff that has sat in a shell for the last 100 years or so.
HOW MANY TIMES DO I HAVE TO TELL YOU!!! :D

Dann2 (public information service No. 1)
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[*] posted on 13-2-2010 at 12:40


The fear generally in some old school chemistry lab stores was from a friction detonation involving the unscrewing of the cap of a dry bottle of picric acid. While PA will pop if struck steel on steel (with a worthy wack) the idea of it popping from something like old Bake-a-lite and glass rubbing together is pretty damn far fetched. The friction unit that I had seen a picture of was a pendulum affair that swung back and forth, passing over another surface. In each proceeding test the "swing-arm" would be pulled further back. I do not know what materials were at the contact points, nor do I know if the armature was "lowered" to a certain depth each time, but the material was give a "-" when compared (by the USBoM) with other materials of which some displayed a certain distance number figure of which indicated how far the thing had to swing.

I have seen a high grade of PA ( about what would comprise a match-head) make a fair noise when placed in Al foil and wacked with a steel hammer on an anvil. That same agenda did not have any effect at all on TNT. But it may have been that somewhere some purity compromised PA shot in a lab when the cap was opened but I have NEVER read where or how.

Of metal picrates I have also NEVER heard of a ferric-picrate being called a primary, yet the inside of shells WERE painted, etc to prevent the materiel from forming. In fact, that would be an interesting experiment, to see if a picrate other than lead would even present a level of sensitivity worthy of being called a primary.

[Edited on 13-2-2010 by quicksilver]
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Rosco Bodine
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[*] posted on 13-2-2010 at 15:59


The fear is unfounded, and is in that category of axiomatic falsehoods known commonly as "old wives tales". The unfounded fear simply does not withstand scrutiny as being justified at any stretch of whatever convoluted rationalizations may be applied, with of course the one exception that fear of any unknown can be elevated to hysteria and seem prudent if the better to be safe than sorry standard is applied......in which case every unknown material encountered should be treated with caution commensurate with the possibility however remote, that
the unknown material might be deadly nerve gas, ebola, or possibly even anti-matter travelling incognito.

It is of course possible there could be a snap crackle pop or even a startling bang from a corroded metal jar cap, and that
would cause apprehension on the occasion of that event, however ...that being said, it is also impossible that such a
snap crackle pop or bang could shoot the entire jarful of material, unless of course the material was something different from picric acid, in which case we are not even talking about picric acid anymore, but guessing about an unidentified material which would be something else.

[Edited on 14-2-2010 by Rosco Bodine]
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[*] posted on 14-2-2010 at 07:17


Quote:
__________________________________________________

unless of course the material was something different from picric acid, in which case we are not even talking about picric acid anymore, but guessing about an unidentified material which would be something else.
__________________________________________________

Indeed, indeed!
Insides of shells were not painted to waste paint in wartime. No, no, no. It's to avoid the evil byproducts. Is TNT used a a reagent? I don't think so but if it were and an old bottle of it was found sitting on a shelf and it was totally unknown who was 'at it' or where it had been etc etc it would have to be treated with some respect.
So regarding those grinding glass tops:
You do not want Picric acid pooping, crackling or snapping all over you (do you?)

Dann2
(Public information source No. 1)

Did you hear about the illigitimate rice crispy?
Snap, crackle and no pop
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[*] posted on 14-2-2010 at 10:51


So, it is only a mere speculation deemed sufficient to justify a full alert EOD response team being called into action, much the same as if an archaeologist were to feel justified in contacting the Egyptian embassy in connection with a student rumor that reposing in Grant's tomb is not the remains of the departed general at all ....but possibly is a mummy ..... saying it is due diligence to inquire concerning the possibly missing King Tut ...they ought to investigate immediately :D

http://www.youtube.com/watch?v=q1LWxo1QqXg&fmt=18 King Tut

http://www.youtube.com/watch?v=CcMRe0FNN00&fmt=18 Valley Of The Kings

[Edited on 14-2-2010 by Rosco Bodine]
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[*] posted on 14-2-2010 at 23:51


Agencies of government responsible for oversight of reactive materials , spell
out detailed specifications for their packaging , handling , and transport.
It's a strange inconsistency then that if screw top containers are deemed a
grave hazard if used with TNP that it has remained the practice , when flip
top mason jars of the type used for preserves have been around for much
longer.

That full article from 1917 posted by entropy51

Picric Acid Explosions.gif - 339kB
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Rosco Bodine
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[*] posted on 15-2-2010 at 06:26


That article squares well with what is "accepted truth" in my own experience.

There is a lot of "stuff" out there in the world which "passes for knowledge"
but is incorrect. I suppose that ultimately we each have to make our own
determination what is the real story on such things. That task alone can
certainly be a legitimate basis for research, to make a determination one
way or another what is true about many matters that are questionable as
to what exactly is true. Experiments are a good way to see for oneself.
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[*] posted on 15-2-2010 at 09:08


It seems that iron and calcium picrates are more sensitive than the parent acid.

http://www.bradfordhistorical.org.uk/antiquary/third/vol03/l...
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[*] posted on 15-2-2010 at 11:00


A commenly forgotten factor is the substantial concentration of lead in the air, which slowly convert the picric acid into lead picrate given enough time...

Reference: -->
http://www.environment.gov.au/soe/2006/publications/drs/indi...

[Edited on 15-2-2010 by nitro-genes]
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[*] posted on 15-2-2010 at 11:24


Calculation models would need to also factor in a percentage reduction of available atmospheric lead caused by the competing lead sequestering capacity of asses in the vicinity, adjusted for the relative saturation level with regards to the maximum capacity realizable for the lead in those asses.
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[*] posted on 15-2-2010 at 12:29


Seriously? Lead in the air having forming enough lead picrate with exposed picric acid to be dangerous? I do not buy it.



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[*] posted on 15-2-2010 at 13:11


Haha, it seems great minds think alike Rosco! :D

I hadn't taken into account these factors, though give or take a few billion years I'm sure it will still have an effect.

Speaking of asses, chemicals used in the lab do tend to have a half life regarding their purity. I've seen bottles of silver nitrate in colours ranging from black to blue/green and Tris base smelling just like yeast extract. Could be a biochemist thing though...
Point is that I would think twice about handeling a bottle of PA that has been around in one of these labs for 30 years. :)

[Edited on 15-2-2010 by nitro-genes]
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Rosco Bodine
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[*] posted on 15-2-2010 at 13:30


A stream of water from a wash bottle is your friend, or if you are in the field....
improvise ......the resulting runoff will be yellow anyway :o

Really I am not a psychologist, but from an engineering perspective it would seem to me that the "bad rap" which has been accorded picric acid is a kind of pyrophobia or a chemophobic variant or combination with that phobia. Maybe it is a sort of obsesssive compulsive paranoia ......
and to perhaps coin a new word
we could call it a pyrochemophobia secondary to or accompanied by acute regulatoritis and anally retentive interventionism presenting as a generalized nanny neurosis or psychosis.

Perhaps some soothing, contemplative music can help smooth those rough spots along the way on one's journey
to enlightenment :cool:

http://www.youtube.com/watch?v=GQGzSTzkibk&fmt=18 Feng Shui

http://www.youtube.com/watch?v=sXG9lEToME0&fmt=18 Shiatsu

http://www.youtube.com/watch?v=DzrmqqD3md4&fmt=18 Feng Shui Twoie

[Edited on 16-2-2010 by Rosco Bodine]
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[*] posted on 29-8-2010 at 11:14


picric acids far from the first or last material organic or otherwise
that the government will deal with using measures usually reserved for nuclear materials.granted meth labs large stashs of drugs easily airborne drugs arent the heathiest places around but with adequate ventilation and throwaway cloth coveralls basic respirators the risks way overblown,same could be said for moldy buildings no one thought twice 20yrs ago about mold and around the same time a rush to remove basically entombed harmless as they were prior to removal and relelase.. asbestos fibers.Far better ways to control a sleeping hazard than intentionally awake the hazard and spread the material building wide. Exposing everone who worked ther with far higher levels than they ever would have had to deal with working there.
basically no ones saying the governments operating using the best information avaliable there simply doing what the laws provide whether is wise or not. its not a war on PA obviously but a war on any number of percieved toxins. another beuacracys dream come true Govts reason for being and an increasing budget to make the buearocrats and gov seem important/nescessary.:(
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[*] posted on 29-8-2010 at 14:07


Quote: Originally posted by franklyn  
A Textbook of Organic Chemistry 1921
http://books.google.com/books/download/A_textbook_of_organic...

While not precisely true , that it is not an explosive itself , the cursory treatment
of this compound reflects the recognition at that time of it's insensitivity , while
noting the reactive nature of the material which is responsible for its undeserved
reputation.

Excerpt from TM-9-1300 Ammunition
http://www.everyspec.com/ARMY/TM+-+Tech+Manual/download.php?...

Acknowledges the shortcomings of both Picric acid and Ammonium Picrate with
regard to it's reactivity which promotes sensitivity. It can explode if heated confined
as inside a shell , otherwise it simply burns.



Well .... under the proper circumstances ..... it's attitude
can be adjusted.

An Explosion Of An Appalling Character.

Report on the Circumstances attending a Fire and Explosion at
Messrs. Roberts, Dale & Co.'s Chemical Works, Cornbrook, Manchester,.
Gov. Rep. No. lxxxi.
Colonel V. D. Majendie, C.B.
In:—The Journal of the Society of Chemical Industry. Vol. VI. No. 12. December
31, 1887

THIS exhaustive report shows that the articles manufactured on the side of the
works where the explosion occurred, were picric acid, nitrate of lead, nitric acid,
hydrochloric acid (nitre cake and salt cake), tin crystals, tin solutions, nitrate of
iron, nitrate of copper, aurin, Manchester brown, Manchester yellow, lakes for
paper stainers and emerald green. Such raw materials as carbolic acid, sulphuric
acid and litharge, the litharge being used for making nitrate of lead, were all
present, the latter salt in very considerable quantity; some nitrate of strontium
was also present.

A fire commenced the catastrophe, this breaking out at or near the stove used
for drying the picric acid. The fire spread quickly, and in five or six minutes an
explosion followed, but not one of an alarming character. This explosion came
from the site of the picric acid stove as nearly as it can be located. It was
followed in something under a minute by a second explosion of an appalling
character, and attended with disastrous results in the shape of damage. One life
was lost.

There is little doubt that the fire was caused by the carelessness of a workman,
who was smoking. Several theories are advanced to explain the first and lesser
explosion, but the second, which was so disastrous, was in all probability due to
the blazing and molten picric acid coming in contact with the litharge placed in
close proximity and with the nitrate of lead and nitrate of strontium. It would at
once combine with these and form fearful explosives. Picric acid alone can
scarcely be called an explosive, but if it comes in contact even with plaster or
lime, it forms a picrate of high explosive character, and it is shown that picric acid
mixed with a little litharge in the cold, produces a mixture which explodes much
more readily than picric acid alone.

Finally, the precaution is urged, that in the manufacture of picric acid the
separation of the acid from all other substances or ingredients, contact with
which would be likely to produce under favorable conditions a picrate or
explosive mixture should be carefully seen to.

"At present picric acid and picrates appear to fall within the category of
'explosives,' and to be subject to the Explosives Act, 1875, only when they are '
used ' or manufactured with a view to produce a practical effect by explosion or
pyrotechnic effect. "

" In view of the present disaster," Colonel Majendie proceeds, "and of the results
of my experiments it will be a matter for careful consideration whether it is not
necessary in the interests of public safety to take advantage of the powers
conferred by the 104th section of the Explosives Act, 1875, and to extend the
definition of explosive to picric acid and all picrates, for whatever purposes
manufactured, and to apply the same provisions of the Act, subject to such
exceptions, limitations and restrictions as may appear reasonable. This point,
however, is one which, in the interests of the trade, as of the public, demands
the fullest and most careful consideration."

As to the storage together and in close proximity of the several substances which
resulted in the formation of such fearful explosives, Colonel Majendie stigmatises
it as the result of negligence.—W. S.



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