Decomposition reactions chemical explosions from

The addition of alkaline chemicals, water, and/or heal may promote self-polyincrizalion and decomposition of hydrogen cyanide. The self-polj ineriaUion reaction is exothermic, and the heat released will promote further polymerization. The heat generation will also result in the decomposition of hydrogen cyanide into anunonia and formate. Tlie pressure rise from polymerization or decomposition reactions can become explosive. Small amounts of acid, such as sulfuric or phosphoric, will help to stabilize tlie hydrogen cyanide against polymerization. 

We see from Eq. (28) that, once the size of a solid chemical of the TD type, placed in the atmosphere under isothermal conditions, is specified in other words, once the values of A H, Aq and E of the exothermic decomposition reaction, in the early stages of the self-heating process, of the solid chemical as well as the values of A and r of the solid chemical are fixed, respectively, the value of S increases with increasing the atmospheric temperature, Ta- There is, however, the upper limit value, or the critical value, of S, i.e., S which S is able to take for a shape of the solid chemical, because there is also the upper limit atmospheric temperature, or the critical temperature, 7)., above which the stationary gradient distribution of temperature in the self-heating solid chemical ceases to be possible, with the result that the temperature of the solid chemical continues to increase acceleratedly to cause the ultimate thermal explosion of the solid chemical. 

It is obvious that the absence of the melting point is characteristic of the DTA curve of a powdery chemical of the TD type. That is, a powdery chemical of this type decomposes prior to melting. The self-heating behavior of a powdery chemical, such as 98 % O, a -azobis(isobutyronitrile) (AIBN), which decomposes explosively prior to any remarkable exothennic decomposition reaction, is also of the TD type, so that the F-K equation is applied to calculate its 1. When confined in the closed cell and subjected to the adiabatic selfheating test started from a in the range of 65 to 74 C, 2 cm of AIBN shows such a self-healing behavior, which is typical of liquid, or powdery, chemicals of the TD type, as exemplified in Fig. 15. 

Fast decomposition reactions have been investigated less extensively. However, with use of the recently available fast detection systems it is possible, in principle, to follow chemical reactions on a microsecond or shorter time scale. The first few steps in the decomposition reaction are of special interest. Due to the formation of, sometimes, reactive species (like NO2, OH, etc.), it is often difficult, if not impossible, to draw up these first steps from a long time scale product analysis of a slowly decomposing explosive. Furthermore, it has been stated that the reactions taking place in the various stages to detonation will probably be different [5]. As these stages will be passed through quickly, fast initiation and detection techniques are necessary. 

What are our options We could purchase hydrogen and oxygen from a chemical manufacturer and have the reactants delivered by truck, or perhaps by rail. But transporting gases is expensive, especially an explosive gas (H2) or a flammable gas (O2). How did we supply H2 and N2 for the ammonia synthesis We produced H2 and N2 on site. Let s investigate producing H2 and O2. What is a good source Water is inexpensive and there are no by-products when it is decomposed. The decomposition reaction... 

Exothermic Decompositions These decompositions are nearly always irreversible. Sohds with such behavior include oxygen-containing salts and such nitrogen compounds as azides and metal styphnates. When several gaseous products are formed, reversal would require an unlikely complex of reactions. Commercial interest in such materials is more in their storage properties than as a source of desirable products, although ammonium nitrate is an important explosive. A few typical exampes will be cited to indicate the ranges of reaction conditions. They are taken from the review by Brown et al. ( Reactions in the Solid State, in Bamford and Tipper, Comprehensive Chemical Kinetics, vol. 22, Elsevier, 1980). 

Explosions involving flammable gases, vapours and dusts are discussed in Chapter 5. In addition, certain chemicals may explode as a result of violent self-reaction or decomposition when subjected to mechanical shock, friction, heat, light or catalytic contaminants. Substances containing the atomic groupings listed in Table 6.7 are known from experience to be thermodynamically unstable, or explosive. They include acetylides and acetylenic compounds, particular nitrogen compounds, e.g. azides and fulminates, peroxy compounds and vinyl compounds. These unstable moieties can be classified further as in Table 6.8 for peroxides. Table 6.9 lists a selection of potentially explosive compounds. 

Glycol/water mixture leaks from jacket into blender, reacts with aluminum powder and sodium hydrosulfite, and initiates exothermic decomposition No—N2 atmosphere, confinement in blender R NOAA Worksheet indicates combining sodium hydrosulfite with ethylene glycol is "explosive due to vigorous reaction or reaction products may produce detonation," "may cause fire," and indicates "flammable gas generation" and "heat generation by chemical reaction, may cause pressurization"... 

SocJ 30, 151-58(1960) (Recent advances in condensed media detonation) 37b) Dunkle s Syllabus (1960-1961), pp 4a 4b (Initiation of shock waves) lOa-lOg (Initiation of deflgrn and deton) p 12a (Frank-Kamenet-skii formulation) p 13b (Initiation by electric discharge) p 13f (Thermal Decomposition and Initiation of Explosives, as discussed by B. Reitzner) pp 17a to 17e (Mechanism of initiation and propagation of detonation in solid explosives) pp 17e 17f [Marlow Skidmore (Ref 31) concluded from their investigations that the problem of shock initiation is somehow related to the temperature distribution in the shock pulse and its effect on the chemical reaction rate. They used an Arrhenius type relationship for the rate increase in the frac-... 

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