Acetone peroxide is an organic peroxide and a primary high explosive. It is produced by the oxidation of acetone to yield a mixture of linear monomer and cyclic dimer, trimer, and tetramer forms. The trimer is known as triacetone triperoxide (TATP) or tri-cyclic acetone peroxide (TCAP). Acetone peroxide takes the form of a white crystalline powder with a distinctive bleach-like odor (when impure) and can explode if subjected to heat, friction, static electricity, strong UV radiation or shock. As a non-nitrogenous explosive, TATP has historically been more difficult to detect, and it has been used as an explosive in several terrorist attacks since 2001.
Video Acetone peroxide
History
Acetone peroxide (specifically, triacetone triperoxide) was discovered in 1895 by Richard Wolffenstein. Wolffenstein combined acetone and hydrogen peroxide, and then he allowed the mixture to stand for a week at room temperature, during which time a small quantity of crystals precipitated, which had a melting point of 97 °C.
In 1899 Adolf von Baeyer and Victor Villiger described the first synthesis of the dimer and described use of acids for the synthesis of both peroxides. Baeyer and Villiger prepared the dimer by combining potassium persulfate in diethyl ether with acetone, under cooling. After separating the ether layer, the product was purified and found to melt at 132-133 °C. They found that the trimer could be prepared by adding hydrochloric acid to a chilled mixture of acetone and hydrogen peroxide. By using the depression of freezing points to determine the molecular weights of the compounds, they also determined that the form of acetone peroxide that they had prepared via potassium persulfate was a dimer, whereas the acetone peroxide that had been prepared via hydrochloric acid was a trimer, like Wolffenstein's compound.
Work on this methodology and on the various products obtained, was further investigated in the mid-20th century by Milas and Golubovi?.
Maps Acetone peroxide
Chemistry
The chemical name acetone peroxide is most commonly used to refer to the cyclic trimer, the product of a reaction between two precursors, hydrogen peroxide and acetone, in an acid-catalyzed nucleophilic addition, although various further monomeric and dimeric forms are possible.
Specifically, two dimers, one cyclic (C6H12O4) and one open chain (C6H14O4), as well as an open chain monomer (C3H8O4), can also be formed; under a particular set of conditions of reagent and acid catalyst concentration, the cyclic trimer is the primary product. A tetrameric form has also been described, under different catalytic conditions. Under neutral conditions, the reaction is reported to produce the monomeric organic peroxide.
Organic peroxides in general are sensitive, dangerous explosives, and all forms of acetone peroxide are sensitive to initiation. TATP decomposes explosively; examination of the explosive decomposition of TATP predicts "formation of acetone and ozone as the main decomposition products and not the intuitively expected oxidation products." Very little heat is created by the explosive decomposition of TATP; the foregoing computational analysis suggests that TATP decomposition as an entropic explosion. However, this hypothesis has been challenged as not conforming to actual measurements. The tetrameric form of acetone peroxide, prepared under neutral conditions using a tin catalyst in the presence of a chelator or general inhibitor of radical chemistry, is reported to be more chemically stable, although still a very dangerous primary explosive.
Some forms of acetone peroxide are prone to loss by sublimation and evaporation.
Several methods can be used for trace analysis of TATP, including gas chromatography/mass spectrometry (GC/MS), high performance liquid chromatography/mass spectrometry (HPLC/MS), and HPLC with post-column derivitization.
Industrial uses
Ketone peroxides, including acetone peroxide and methyl ethyl ketone peroxide, find application as initiators for polymerization reactions, e.g., silicone or polyester resins, in the making of fiberglass-reinforced composites. For these uses, the peroxides are typically in the form of a dilute solution in an organic solvent; methyl ethyl ketone is more common for this purpose, as it is stable in storage.
Acetone peroxide is used as a flour bleaching agent to bleach and "mature" flour.
Acetone peroxides are unwanted by-products of some oxidation reactions such as those used in phenol syntheses. Due to their explosive nature, their presence in chemical processes creates potential hazardous situations. Numerous methods are used to reduce their appearance as byproducts--for instance, shifting pH to more alkaline, adjusting reaction temperature, or adding inhibitors of their production. Acetone peroxides are also the unwanted product of air-induced oxidation of diisopropyl ether.
Use in improvised explosive devices
TATP has been used in bomb and suicide attacks and in improvised explosive devices, including the London bombings on 7 July 2005, where four suicide bombers killed 52 people and injured more than 700. It was one of the explosives used by the "shoe bomber" Richard Reid in his 2001 failed shoe bomb attempt and was used by the suicide bombers in the November 2015 Paris attacks, 2016 Brussels bombings, 2017 Manchester Arena bombing, 2017 Brussels Central Station bombing, 2017 Parsons Green bombing, and the 2017 Stockholm attack.
TATP is attractive to terrorists because it is easily prepared from readily available retail ingredients, such as hair bleach and nail polish remover. It is also able to evade detection because it it is one of the few high explosives that do not contain nitrogen--and can therefore pass undetected through traditional explosive detection scanners designed to detect nitrogenous explosives. Several detection devices for TATP have however now been developed.
A key disadvantage is its high susceptibility to accidental detonation (and resulting "workplace accidents" in bomb-making shops), which has led to TATP being referred to as the "Mother of Satan." TATP was found in the accidental explosion that preceded the 2017 terrorist attacks in Barcelona and surrounding areas.
References
External links
- ChemSub Online: Acetone peroxide - Triacetone triperoxide.
Source of article : Wikipedia
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