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Paul L. Damour Andrew Freedman Joda Wormhoudt 《Propellants, Explosives, Pyrotechnics》2010,35(6):514-520
The vapor pressures of TATP over the temperature range 269.85–306.95 K and DADP over the temperature range 265.85–294.85 K were determined using a modified Knudsen effusion apparatus. The Clausius‐Clapeyron plot of log10(p(Pa)) with 1/T provided a straight line for each material. This expression for TATP is log10(p(Pa))=−(4497±80)/T(K)+(15.86±0.28) (error limits are 95 % confidence limits) and for DADP it is log10(p(Pa))=−(4417±137)/T(K)+(16.31±0.48). These expressions yield values of the vapor pressure at 298.15 K of 6 Pa for TATP and 17 Pa for DADP, and heats of sublimation of 86.2±1.5 kJ mol−1 for TATP and 84.6±2.6 kJ mol−1 for DADP. Attempts were made to determine the vapor pressure of HMTD but it appears to have a vapor pressure too low for our system to reliably determine. A two month experiment did provide an upper limit estimate for the vapor pressure of HMTD of approximately 0.04 Pa at room temperature. Melting point and melting point range were used as verification of the identity and purity of the TATP and DADP used in these experiments, but this was not possible with HMTD since it detonates prior to melting. 相似文献
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Jimmie&#x;C. Oxley James&#x;L. Smith Kajal Shinde Jesse Moran 《Propellants, Explosives, Pyrotechnics》2005,30(2):127-130
Using a GC headspace measurement technique, the vapor pressure of TATP was determined over the temperature range 12 to 60 °C. As a check on the experimental method, TNT vapor pressure was likewise computed. Values for TNT are in excellent agreement with previous published ones. For TATP the vapor pressure was found to be ~ 7 Pa at ambient conditions. This value translates to a factor of 104 more molecules of TATP in air than TNT at room temperature. The dependence of TATP vapor pressure on temperature can be described by the equation log10P(Pa)=19.791−5708/T(K). Its heat of sublimation has been calculated as 109 kJ/mol. 相似文献
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Jimmie C. Oxley James L. Smith Joseph E. Brady Lucus Steinkamp 《Propellants, Explosives, Pyrotechnics》2014,39(2):289-298
Acid catalyzes the formation of triacetone triperoxide (TATP) from acetone and hydrogen peroxide, but acid also destroys TATP, and, under certain conditions, converts TATP to diacetone diperoxide (DADP). Addition of strong acids to TATP can cause an explosive reaction, while reaction with dilute acid reduces the decomposition rate so drastically that gentle destruction of TATP is impractical. However, combined use of dilute acid with slightly solvated TATP made gentle destruction of TATP feasible. Variables including acid type, concentration, solvent and ratios thereof have been explored, along with kinetics, in an attempt to provide a field‐safe technique for gently destroying this homemade primary explosive. The preferred method is moistening TATP with an alcoholic solution (aqueous methanol, ethanol, or iso‐propanol) followed by addition of 36 wt‐% hydrochloric acid. Preliminary experiments have shown the technique to be safe and effective for destruction of hexamethylene triperoxide diamine (HMTD), as well. 相似文献
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Jimmie C. Oxley James L. Smith Patrick R. Bowden Ryan C. Rettinger 《Propellants, Explosives, Pyrotechnics》2013,38(2):244-254
Conditions, which result in the formation of triacetone triperoxide (TATP) or diacetone diperoxide (DADP) from acetone and hydrogen peroxide (HP, were studied for the purposes of inhibiting the reaction. Reaction of HP with acetone precipitates either DADP or TATP, but the overall yield and amount of each was found to depend on (1) reaction temperature, (2) the molar ratio of acid to HP/acetone, (3) initial concentrations of reactants, and (4) length of reaction. Controlling molar ratios and concentrations of starting materials was complicated because both sulfuric acid and hydrogen peroxide were aqueous solutions. Temperature exercised great control over the reaction outcome. Holding all molar concentrations constant and raising the temperature from 5 to 25 °C showed an increase of DADP over TATP formation and a decrease in overall yield. At 25 °C a good yield of TATP was obtained if the HP to acetone ratio was kept between 0.5 : 1 and 2 : 1. At constant temperature and HP‐to‐acetone held at one‐to‐one ratio, acid‐to‐HP molar ratios between 0.10 : 1 and 1.2 : 1 produced good yield of TATP. Plotting the molality of HP vs. that of sulfuric acid revealed regions, in which relatively pure DADP or pure TATP could be obtained. In addition to varying reaction conditions, adulterants placed into acetone were tested to inhibit the formation of TATP. Because there is much speculation of the relative stability, sensitivity, including solvent wetting of crystals, and performance of DADP and TATP, standard tests (i.e. DSC, drop weight impact, and SSED) were performed. 相似文献
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Jimmie C. Oxley James L. Smith Lucus Steinkamp Guang Zhang 《Propellants, Explosives, Pyrotechnics》2013,38(6):841-851
A comprehensive mechanistic study regarding acetone peroxides reveals that water has a profound effect on the formation of the solid cyclic peroxides, TATP, and DADP. The identification and rate of occurrence of reaction intermediates as well as compositions of the final products offer explanation for previously reported results indicating that acid type and hydrogen peroxide concentration affect the acid catalyzed reaction between acetone and hydrogen peroxide. A kinetics study of the decomposition of TATP revealed the effects of water and alcohols. They generally retard conversion of TATP to DADP and lead to complete decomposition of TATP by acid. A mechanism is proposed for the production of TATP and DADP. 相似文献
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Joseph E. Brady James L. Smith Casuarina E. Hart Jimmie Oxley 《Propellants, Explosives, Pyrotechnics》2012,37(2):215-222
Vapor pressure is a fundamental physical characteristic of chemicals. Some solids have very low vapor pressures. Nevertheless numerous chemical detection instruments aim to detect vapors. Herein we address issues with explosive detection and use thermogravimetric analysis (TGA) to estimate vapor pressures. Benzoic acid, whose vapor pressure is well characterized, was used to calculate instrumental parameters related to sublimation rate. Once calibrated, the rate of mass loss from TGA measurements was used to obtain vapor pressures of the 12 explosives at elevated temperature: explosive salts – guanidine nitrate (GN); urea nitrate (UN); ammonium nitrate (AN); as well as mono‐molecular explosives – hexanitrostilbene (HNS); cyclotetramethylene‐tetranitramine (HMX), 4,10‐dinitro‐2,6,8,12‐tetraoxa‐4,10‐diaza‐tetracyclododecane (TEX), cyclotrimethylenetrinitramine (RDX), pentaerythritol tetranitrate (PETN), 3‐nitro‐1,2,4‐triazol‐5‐one (NTO), 1,3,3‐trinitroazeditine (TNAZ), triacetone triperoxide (TATP), and diacetone diperoxide (DADP). Ambient temperature vapor pressures were estimated by extrapolation of Clausius‐Clapeyron plots (i.e. ln p vs. 1/T). With this information potential detection limits can be assessed. 相似文献
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Michael&#x;D. Joseph Suresh&#x;K. Jangid Ravindra&#x;S. Satpute Bhagwan&#x;G. Polke Tribhuran Nath Shri&#x;N. Asthana Alapati&#x;Subhananda Rao 《Propellants, Explosives, Pyrotechnics》2009,34(4):326-330
Hydroxyl‐terminated polybutadiene (HTPB) based sheet explosives incorporating insensitive 1,3,5‐triamino‐2,4,6‐trinitrobenzene (TATB) as a part replacement of cyclotrimethylene trinitramine (RDX) have been prepared during this work. The effect of incorporation of TATB on physical, thermal, and sensitivity behavior as well as initiation by small and high caliber shaped charges has been determined. Composition containing 85% dioctyl phthalate (DOP) coated RDX and 15% HTPB binder was taken as control. The incorporation of 10–20% TATB at the cost of RDX led to a remarkable increase in density (1.43→1.49 g cm−3) and tensile strength (10→15 kg cm−2) compared to the control composition RDX/HTPB(85/15). RDX/TATB/HTPB based compositions were found less vulnerable to shock stimuli. Shock sensitivity was found to be of the order of 20.0–29.2 GPa as against 18.0 GPa for control composition whereas their energetics in terms of velocity of detonation (VOD) were altered marginally. Differential scanning calorimeter (DSC) and thermogravimetry (TG) studies brought out that compositions undergo major decomposition in the temperature region of 170–240 °C. 相似文献
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《Propellants, Explosives, Pyrotechnics》2017,42(4):370-375
In Brazil, automated teller machine (ATM) has become a major target of theft incursions toward explosion. Efficient analysis of explosives residues on suspect banknotes is a serious issue in forensic labs, and guide to the crime solution. Easy ambient sonic‐spray ionization mass spectrometry (EASI‐MS) is shown to be a simple and selective screening tool to identify peroxide explosives on real banknotes collected from ATM explosion. Analyses were carried out directly on the banknotes surfaces without any sample preparation, identifying triacetone triperoxide (TATP) and diacetone diperoxide (DADP). Homemade EASI source was coupled to ultrahigh‐resolution and ultrahigh accuracy FT‐ICR MS and revealed the ion of m /z 245 correspondent to sodiated TATP [C9H18O6Na]+ and the ion of m /z 171 related to sodiated DADP [C6H12O4Na]+, ions that is the sodiated DADP and the ions of m /z 173 and 189 related to [C6H14O4Na]+ and [C6H14O4K]+, respectively, which are associated to chemical markers of TATP domestic route synthesis. EASI source coupled to a single quadrupole mass spectrometer provides an intelligent and simple way to identify the explosives TATP, DADP and its domestic synthesis markers. 相似文献
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Jimmie C. Oxley James L. Smith Matthew Porter Lindsay McLennan Kevin Colizza Yehuda Zeiri Ronnie Kosloff Faina Dubnikova 《Propellants, Explosives, Pyrotechnics》2016,41(2):334-350
The synthesis and decomposition of hexamethylene triperoxide diamine (HMTD) were studied. Mechanisms were proposed based on isotopic labeling and mass spectral interpretation of both condensed phase products and head‐space products. Formation of HMTD from hexamine appeared to proceed from dissociated hexamine as evident from scrambling of the 15N label when synthesis was carried out with equal molar labeled/unlabeled hexamine. Decomposition of HMTD was considered with additives and in the presence and absence of moisture. In addition to mass spectral interpretation, density functional theory (DFT) was used to calculate energy differences of transition states and the entropies of intermediates along different possible decomposition pathways. HMTD is destabilized by water and citric acid making purification following initial synthesis essential in order to avoid unanticipated violent reaction. 相似文献
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A two‐phase flashing flow model is developed to predict the distributions of pressure, temperature, velocity and evaporation rate in a transfer line, which is a typical example of a two‐phase flow pipe in the petrochemical industry. The model is proposed based on the pressure drop model and the multi‐stage flash model. The results indicate that pressure drop, temperature drop, and change of evaporation rate mainly occur in the transition section and the junction site of the transfer line. The predictions of the model have been tested with reliable field data and the good agreement obtained may lead to a better understanding of the two‐phase flashing flow phenomenon, as well as demonstrating the feasibility of applying the model into the design and optimization of pipelines. 相似文献