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A visualization of the solvent/TATB mix. The red, white, blue and gray moleculese are the explosive, TATB, the green balls are the fluoride anions and the blue/gray regions are the organic cation portion of the solvent. The new solvent promises less toxic processing and safer nuclear weapons, among other potential benefits.  (Source: LLNL)

Commercial grade TATB is shown on the left. Performance is directly correlated to the crystal quality. The new organic solvent-produced TATB is on the right, and offers visibly superior crystals and the vastly superior performance.  (Source: LLNL)
Researchers are replacing toxic inorganic compounds, with "greener" organic compounds during processing

Explosives and green tech aren't two things you might always think of as going hand in hand.  However, new breakthrough research from the Lawrence Livermore National Laboratory (LLNL) not only promises to improve conventional explosives, but also make processing less toxic through the use of organic compounds.

The research focuses on a class of compounds known as molecular crystals.  Molecular crystals are extremely powerful compounds that are also surprisingly stable.  They are used in drugs, pigments, agrochemicals, dyes and optoelectronics, as well as in explosives.  Since many of these compounds in unusable disordered form are bound together by strong hydrogen bonds, processing via typical organic solvents in nearly impossible due to lack of solubility.

As a result, toxic inorganic solvents are typically used to partially dissolve and reform the material into useful crystals.  The process is inefficient and produces toxic byproducts, such as ammonium chloride.

Researchers at the LLNL, under the Transformational Materials Initiative (TMI) Laboratory Research and Development project, discovered a class of organic solvents that could be used and would process the material more efficiently.  They turned to ionic liquids – a special type of molten salt that becomes liquid under the boiling point of water (100 degrees Celsius).  This type of solvent is considered attractive due to its lack of vapor pressure and tendency not to evaporate even under high temperature (evaporation of solvents can yield toxic fumes and also limits the usable liquid).  Also, scientists can custom tailor the types of positive and negative ions they want to use.

Lead author Amitesh Maiti used quantum simulations to narrow the selection of ions to a class of solvents with fluoride ions, which is very good at dissolving hydrogen bonds.  He describes, "The design of custom solvents through first principles modeling opens up new possibilities for the dissolution of materials that are hard to dissolve."

After the theoretical work was complete, researchers led by Phil Pagoria tested dissolving and reforming molecular crystals with the solvent.  The result was large defect-free (97 percent pure) crystals, which were vastly superior to current commercial offerings.

The key crystal compound tested was a special type of explosive known as TATB (1,3,5-triamino-2,4,6-trinitrobenzene).  This explosive is widely used for its exceptional stability by the Department of Energy, the Department of Defense and the mining industry.  The refined crystalline version is even more stable.  Larry Fried, the project’s principal investigator and a co-author of the paper states, "Improving crystal quality and purity leads to explosive materials that are safer (less likely to react violently) when subjected to mechanical impact or heat."

This is of particular interest to national security, as TATB is thought to be used in all of Britain's nuclear warheads, and the majority of the U.S.'s warheads as a detonator, due to its already favorable stability.  The purer crystals could provide detonators capable of surviving even more severe punishment without an accidental detonation.

Aside from TATB the technique could be used to process a broad array of other commercial substances containing molecular crystals, including polymers (plastics) and molecular solids (pharmaceuticals, paints, propellants, explosives).  For example, the same solvents were shown to break down cellulose into basic sugars.  This could prove a boon to efforts to create ethanol and other biofuels from cellulose, a typically energetically intensive process.

In the short term it means the ability to not only process higher quality, safer TATB, but to minimize the environmental impact from processing.

The research is reported in the Sept. 1 issue of the journal Physical Chemistry Chemical Physics.

Other researchers on the project included Alex Gash, Yong Han, Christine Orme and Richard Gee.  



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RE: Organic Bombs
By Digimonkey on 9/2/2008 10:03:12 PM , Rating: 2
The biggest difference is that civilians weren't the targets. Hiroshima hosted a major part of the Japanese military power, also a lot of the non essential citizens (kids) had been evacuated before the atomic bomb was dropped.


RE: Organic Bombs
By 16nm on 9/2/2008 11:06:59 PM , Rating: 2
quote:
The biggest difference is that civilians weren't the targets.


Actually, they probably were. Remember, the emperor called on ALL of his people to fight a possible American invasion. After Iwojima, American forces were very much uninterested in fighting a gorilla war with the Japanese. Iwojima convinced us that invasion would not be a stroll through the park.

What's worth noting is that America and Japan are close allies and at total peace with one another.


RE: Organic Bombs
By JS on 9/3/2008 10:44:50 AM , Rating: 2
Of course civilians were targets. Perhaps not primarily for the nuclear bombs but definitely for the bombings of Berlin, Dresden and other German cities. The allies wanted to kill factory workers and demoralize the enemy. And in the case of Dresden, probably exact a little revenge.


RE: Organic Bombs
By Myg on 9/3/2008 11:55:11 AM , Rating: 2
Can we just get this 10000 pound gorilla out in the open for once?

America and the Allies did sick, disgusting things just like everyone else who wanted to vent their anger; the people who took part in these atrocities (Generals/soldiers/pilots/etc..) were no better then the German/Soviet army or anyone else who tried to hide from the fact that they were supporting the mass killing of people.

I always find it totaly disgusting when I see veterens trying to hide behind "orders" and "that it was war" excuses; because that somehow makes it ok.

To touch on a side point which was mentioned in this threading:
If your in-tune with Muslim teachings; you will find it is commonly taught that there exists the "Muslim World" and the "Rest". The western world being the worst of the "Rest"; and heres the kicker for the lot of you who miss this point: They say "that it was war" when they try to excuse their actions...

Funny how the world works eh? We are all the same, really; all trying to blame others for causing us to do things. This aint the garden of eden (Adam blames Eve, Eve blames snake). We are supposed to know better; and we do.

The point being is that its not the event; its the intent that matters.
Americans wanted to murder Japanese Civilians, they did so, Germans wanted to murder their own + Soviets, they did so,
British wanted to murder the Germans, they did so,
Soviets wanted to murder themselves + Germans, they did so, Japanese wanted to murder the Chinese, they did so...

None of these actions can be escaped from, by either death or denying them. They will permanently perpetuate themselves towards the disorder of the current formation of society untill proper acknowledgement is issued and apologies are provided all around.

Anyways... Back to the more ecologically friendly weapons of mass destruction :-)


RE: Organic Bombs
By Seemonkeyscanfly on 9/9/2008 6:29:39 PM , Rating: 2
"The point being is that its not the event; its the intent that matters. Americans wanted to murder Japanese Civilians"

Incorrect. Americans did not want to get into war at all (except selling weapons, which helped end the Great Depression). Once dragged into the war, the American wanted to end it. The bombs did just that, otherwise millions more would have died (both sides). If the US wanted Japanese Civilians dead, there would have been many more bombings....40 or 50 more (yes, it would have taken time, but know one would have stopped them).

“(Adam blames Eve, Eve blames snake).” Adam blamed Eve, yes. Eve does not blame any one. Adam, really gets in trouble for not controlling his wife's action (letting her eat the forbidden fruit). If Adam was honest with GOD saying, well the serpent told us how we would not die from eating the fruit and we believed him. The human race might not have been punished in the same manner. Instead Adam says some to the effect of, Well Eve picked it and eat of it first.


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