Acetone peroxide is an organic peroxide explosive made from two common household chemicals: acetone and hydrogen peroxide. It exists in several forms, but the most well-known is the trimer, called triacetone triperoxide (TATP), with the molecular formula C₉H₁₈O₆. First synthesized by the German chemist Richard Wolffenstein in 1895, it remained a chemical curiosity for nearly a century before gaining notoriety in the 1980s as a weapon used in improvised explosives.
Chemical Structure and Forms
When acetone reacts with hydrogen peroxide in the presence of an acid catalyst, the result is a white crystalline powder. The reaction can produce several different molecular arrangements. The monomer is a simple, single-unit molecule (C₃H₈O₄), also called 2,2-dihydroperoxypropane. Two of these units can link together to form a dimer (known as DADP), and three can form a ring-shaped trimer, which is TATP. Real-world batches are typically a mixture of these forms, with the specific ratio depending on the acid used and the reaction conditions.
TATP is the form most associated with explosive use. Its six-membered ring of alternating oxygen atoms and carbon bridges gives it a high degree of internal strain, which is central to why it releases energy so violently when disturbed.
What Makes It Unusual as an Explosive
Most familiar explosives, like TNT or dynamite, release energy primarily through heat. TATP works differently. A 2005 study published in the Journal of the American Chemical Society found that its detonation is not driven by a large release of thermal energy. Instead, it’s classified as an “entropic explosion.” When a single molecule of solid TATP decomposes, it produces three molecules of acetone gas and one molecule of ozone. That sudden jump from one solid molecule to four gas molecules creates an enormous, rapid expansion in volume. It’s the sheer increase in the number of gas molecules, not a massive fireball, that generates the blast wave.
This mechanism also means TATP is slightly less powerful than TNT on a weight-for-weight basis, but still devastating in practice.
Physical Properties
TATP is a white crystalline solid with a melting point of roughly 93 to 98°C. One of its defining and most dangerous physical traits is its high vapor pressure. At room temperature, TATP has a vapor pressure of about 0.05 mmHg. That may sound trivial, but it’s far higher than conventional military explosives. For comparison, TNT only begins to noticeably sublimate (transition from solid directly to gas) when heated, while TATP does so constantly at room temperature. This means a sample left sitting on a shelf is slowly evaporating and shrinking over time, filling the surrounding air with detectable vapors.
Extreme Sensitivity and Instability
TATP is notoriously sensitive to friction, impact, heat, and even static electricity. It functions as a primary explosive, meaning it can detonate from relatively minor physical disturbance rather than requiring a separate detonator. This makes it extraordinarily dangerous to produce, transport, and store.
Storage introduces additional risks. The acid used during synthesis, leftover impurities, and even the container material can accelerate decomposition. Research from forensic laboratories has shown that impurities in crude, homemade TATP make it even less stable than laboratory-grade samples. The acid catalyst (commonly hydrochloric acid) can leave behind reactive byproducts like chloroacetone that further destabilize the material over time. Forensic headspace samples have been shown to degrade within a month of storage, complicating both evidence preservation and criminal investigations.
Crude batches are particularly unpredictable. The mixture of monomer, dimer, and trimer forms, combined with unreacted precursors and acid residues, creates a material whose sensitivity can change day to day. There is no reliable way to make it “safe” for handling.
Why It’s Difficult to Detect
Most conventional explosive detectors are designed to pick up nitrogen-containing compounds, since the vast majority of military and commercial explosives contain nitrogen. TATP contains no nitrogen at all. It’s made entirely of carbon, hydrogen, and oxygen, which means standard security screening equipment can miss it entirely.
Its unusually high vapor pressure is, paradoxically, what makes detection possible through other means. Because TATP releases a steady stream of vapor at room temperature (about 6 nanograms per 10 microliters of air), trained explosive-detection dogs can identify it by scent. Newer analytical technologies, including differential ion mobility spectrometry, have been developed specifically to fill the gap left by traditional nitrogen-focused detectors. These instruments ionize airborne molecules and identify them based on how they move through an electric field, allowing them to distinguish TATP from background air chemistry.
Regulation of Precursor Chemicals
Because TATP can be made from widely available chemicals, governments have focused on restricting access to its raw ingredients rather than the finished product. In the European Union, regulations introduced in 2021 place hydrogen peroxide in a “restricted” category, meaning it cannot be sold to the general public above specific concentration limits. Acetone falls into a separate “reportable” category: it can still be purchased, but retailers are required to flag suspicious transactions to authorities.
In the United States, the approach is less uniform. There is no single federal law restricting the purchase of hydrogen peroxide or acetone at consumer concentrations, but high-concentration hydrogen peroxide (above roughly 30%) is tracked by suppliers, and the manufacture of any explosive device is a federal crime. Retailers of beauty supply and pool chemicals, the most common sources of concentrated hydrogen peroxide, increasingly follow voluntary reporting guidelines.