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Kozak G. D., Tsvigunov A. N., Akinin N. I.

Central European Journal of Energetic Materials

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2011

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Vol. 8, nr 4

249-260

EN

Properties that cause explosion hazard of organic peroxides, hydroperoxides and nitrocompounds are examined in the article. Ability to thermal explosion initiation of benzoyl peroxide and of nitrocompounds is compared. Explosion properties of peroxides are analyzed. Measurements of burning temperature by means of micro thermocouples and the comparison of their values with the calculated ones of benzoyl peroxide and hydroperoxide of isopropyl benzene lead to the conclusion that burning of them propagates in condensed phase. It is noted that heat instability of benzoyl peroxide burning, contrary to many nitrocompounds, is absent. Burning of benzoyl peroxide is stable even in vacuum. It is noted that, although benzoyl peroxide is not applied as explosive, in some cases the explosion hazard of benzoyl peroxide heating can be bigger than that of PETN. This conclusion was made on the basis of an investigation carried out by means of DSC method. The explosion process of benzoyl peroxide and hydroperoxide of isopropyl benzene propagates in a regime reminiscent of a low velocity detonation and the explosive effects are suffcient for severe destructions during accidents. This conclusion unfortunately is confrmed by bitter experience in practice. The results of the investigation of condensed products of explosion at impact of mixtures aluminum with peroxides and with nitrocompounds by means of impact-testing machine that were carried out in this work by X-ray diffraction analysis are discussed. It was shown that if the temperature of explosion of a mixture is Tp ≥ 2200-2300 K, practically all aluminum or aluminum hydride in the mixture transformed into aluminum oxide.

2

Hazard of Runaway of Nitration Processes in Nitrocompounds Production

Kozak G. D., Raikova V. M.

Central European Journal of Energetic Materials

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2010

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Vol. 7, nr 1

21-32

EN

Hazard of runaway of nitration processes in nitrocompounds production was investigated. Temperature rise in DNT nitration mixes under near adiabatic conditions was measured, and derivative dT/dζ was computed. Heat evolution rate caused by nitration (primary reaction) and oxidation (secondary reaction) were examined by means of elaborated mathematical model. Limiting values of T and dT/dζ for safe process were determined. The second part of investigation concerns detonability of solutions of nitrocompound in sulfuric acid. The detonation failure diameter df and detonation velocity D of solutions of trinitrotoluene, dinitrotoluene, and trinitrobenzene in sulfuric acid and oleum have been measured in the wide range of concentrations at T = 90C. It was shown that the detonability of the nitrocompounds depends signifcantly on the sulfuric acid content. The minimum value of df for the mixture TNT/oleum is about 2 mm, i.e., 30 times less, than that for melted TNT, and practically equals to df of nitroglycerine.

3

Forensic Investigation of Some Peroxides Explosives

Kuzmin V. V., Solov'ev M. Y., Tuzkov Y. B., Kozak G. D.

Central European Journal of Energetic Materials

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2008

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Vol. 5, nr 3-4

77-85

EN

Some of pe roxide s : t r i a c e tone t r ipe roxide (TATP) , hexamethylenetriperoxidediamine (HMTD) have been used recently as "irregular" explosives for delinquency and international terrorism purposes. The intimate knowledge of properties and methods of analysis of these substances is necessary for experts. Forensic investigations of some peroxides explosives: triacetonetriperoxide (TATP) and hexamethylenetriperoxidediamine (HMTD) were carried out in this work. The detonation process of peroxides initiation by means of pyroxylin layer ignition was investigated, velocity of detonation at apparent density (ρ HMTD = 0.38 g/cm3, ρ TATP = 0.47 g/cm3) was measured by means of a Russian fotoregister GFR-3. These data were compared with literature detonation velocity values that had been measured at larger densities. The values of detonation velocities complement each other rather well, linear dependencies of D vs. ρ found at densities ρ = 0.35-1.2 g/cm3. The high sensitivity of the investigated analytical methods, that were applied (10-5 -10<-8 g) facilitate the determination of possible times for finding traces of TATP after an explosion. Time t = 6 hours after explosion is the critical time for finding peroxides traces of TATP on a metal surface by means of analytical methods used in this work.

4

Explosion Hazard of Aromatic Organic Compounds Containing One or Two Nitrogroups

Kozak G. D., Vasin A. Y., Dyachkova A. V.

Central European Journal of Energetic Materials

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2008

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Vol. 5, nr 2

49-55

EN

Aromatic compounds containing one or two nitrogroups use in chemical industry commercially, in the first place there are mono- and di- nitroderivatives of benzene and toluene. Some industrial incidents at heat selfignition of them, and explosive properties of them were discussed in literature. This investigation deals with explosion hazard of less investigated in this regard class nitrocompounds - azo-dyes. All azo-dyes contain azo or amino groups, two benzene circles with substituents. Some of them contain one or two nitrogroups. Nitro- and azo- groups can give explosion hazard to organic substance. Temperature of fast decomposition beginning at heating and kinetic parameters of slow decomposition were experimentally measured for nine of them. The enthalpies of formation were measured experimentally, and explosion parameters were calculated for three of them. These results gave an opportunity to calculate the temperatures of heat explosion on a base of fundamental theory of heat explosion at convection heat transfer with environment. It was found that calculated temperatures of heat explosion agreed with experimental temperatures of fast decomposition beginning at heating, the divergence was 4.5% on average. Thus it was shown that investigated azo-dyes were the weak explosives, and theory of heat explosion could be quite applied to them.

5

Cast Porous Charges on a Base of Ammonium Nitrate-Urea Eutectic

Litovka O. B., Kozak G. D., Chugreeva E. Y., Starshinov A. V.

Central European Journal of Energetic Materials

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2008

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Vol. 5, nr 2

57-66

EN

There are great number tasks of explosive technique, requiring the charges with low pressure and detonation velocity. Powerful tool of regulation of these parameters is lowering of charge density. The main goal of this work is elaboration of technology of manufacture and investigation of explosive properties of charges on a base of eutectic ammonium nitrate-urea mixtures (AN/UR) that have melting point T[m] < 100 C. The physicochemical properties of these mixtures were investigated by means of DSC method and fusion diagram of them was plotted. The composition AN/UR 80/20, that has Tm= 80-90 C was chosen for subsequent investigation. The molten composition was mixed with fine aluminum powder, portion of it was placed into paper tube. The level of a liquid was less than length of the tube. Crystallization of melted mixtures was carried out in vacuum chamber, the level of liquid increased at pumping because of expansion of air bubbles introduced with aluminum particles and reached the upper cork of tube. In such a way porous charges were formed. The dependence of charge density vs. population of tubes by melted mixtures was plotted. Calculated heat explosion of mixtures at content of aluminum Al = 10-15% is Qv = 4.5-5.3 MJ/kg, calculated detonation velocity at density ρ = 0.5-1 g/cm3 changes from D = 3.2 to 5.2 km/s. Detonability of charges was investigated experimentally. Failure diameter (df) of detonation was measured, it was df = 22 mm (ρ = 0.6-0.7 g/cm3) for charges without confinement at initiation by means of booster or blasting cap.

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Calculation of Thermochemical and Explosive Characteristics of Furoxanes

Zhukov I., Kozak G. D.

Central European Journal of Energetic Materials

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2008

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Vol. 5, nr 3-4

45-54

EN

Search of high-power energetic materials is one primary line of development of chemical physics of combustion and explosion. Yield of such materials is usually very small, and its cost is very high. Calculation of unknown characteristics and properties is the only way out from this situation. There are different methods today that allow calculating unknown detonation performance and some of physicochemical properties. Examination of calculated detonation performance of furoxanes and benzofuroxanes compounds that are not enough investigated is presented in this work. These compounds are new high-power energetic materials. Influence of error in enthalpy of formation of these compounds on their detonation performance is also examined in this work. Furoxanes plays particular part among energetic materials. They are convenient blocks of molecules of high-power energetic materials. Joining of explosiphorus clusters of atoms are lead to obtaining of number of high-performance compounds. It is caused by flatten structure of furoxane ring, that lead to high density of compounds and are characterized by high and positive value of enthalpy of formation. Detonation performance of furoxanes was not study practically. That is why 10 furoxanes have been chosen as object of study (see Nomenclature). 7 of 10 studied furoxanes have anomalous elemental composition, because they are hydrogenfree. In order to evaluate possible error in computational detonation performance, explosive characteristics of 6 hydrogen-free energetic materials with known experimental data have been calculated.