Tetryl decomposition rate

Burning of tetryl is discussed in the monograph by Glazkova [92] and reference is given to the early work of Hinshelwood [93] who pointed out that thermal decomposition of tetryl produces picric acid which plays the part of a catalyst of the decomposition. The rate of burning of tetryl under pressure increases by addition of potassium bichromate, according to Glazkova [92]. 

Kinetics of isothermal decompn of K perchlorate) 3) Inst of Study of Rate Processes, Univ of Utah, "The Isothermal Decomposition of Tetryl and Hydrazine Nitrate , TechRept No XL111 (Dec 1954) Contract N7-onr-45107 4) R.M. 

If decomposition proceeds at the same rate over entire range until practically no sample remains (like with(AN),it is said that the explosive exhibits (ideal) first-order decomposition, and that no autocatalyzation takes place as in the decompn of.PETN,Tetryl or RDX. EDNA followed the first-order decomposition law only until ca 5% of the expl had decomposed. This was followed by autostabilization, the term applied here on the supposition that one of the condensed decompn products of EDNA which accumulated in the sample apparently tended to stabilize it, thus slowing down the decompn. After ca 10% of the expl had decomposed, however, autocatalysis developed... 

For every 10 °C increase in temperature, the rate of decomposition is approximately doubled, but may increase as much as 50 times if the explosive is in the molten state. The rates of decomposition depend on the condition of storage and the presence of impurities which may act as catalysts. For example, nitroglycerine and nitrocellulose decompose at an accelerated rate due to autocatalysis, whereas the decomposition rate of TNT, picric acid and tetryl can be reduced by removing the impurities which are usually less stable than the explosive itself. With many of the explosives the presence of moisture increases the rate of decomposition. 

Properties Brownish crystals. Melts with decomposition at 210° and deflagrates at about 226 . Powerful and sensitive high explosive, similar to Tetryl. Detonation rate (d = 1.6) 7500 m/sec. On long storage stability not very satisfactory, particularly in presence of moisture, which tends to promote hydrolysis.37... 

The stirrers were made of stainless steel, since kinetic studies - showed that stainless steel does not affect the rate of thermal decomposition of the substances investigated. In order to choose the method of stirring, the viscosity and its temperature dependence were determined in an Ostwald viscometer for DINA (dinitroxydiethylnitramine) and for tetryl. The viscosity of DINA at the temperatures of the experiment is similar to that of water at room temperature. Therefore water was used as a model of DINA in the preliminary estimation of the efficiency of the stirring. A propeller stirrer was used for stirring DINA. In order to avoid the distortion of the surface of the stirred substance the axle of the stirrer was placed... 

ITC heating of Iclryl increases the rate of burning of the substance. Tlus was already shown by Andreev (V ol. Ill, Fig. 6), by his later work [94J and substantiated by M. M. Jones and Jackson [87] and Japanese authors [86). Tire latter authors found for example that preheating the sample to 180 C lowers its ni.p. by 20 C and the decomposition temperature by 12 C. They also examined the samples of tetryl heated at 165°C for 3 hours by liquid chromatography, by TLC, NMR and mass specirography. They found that 2,4.6-trinitroanisol and picric acid are fonned on the thermal decomposition of tetryl at I60--200 C. 

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