EXOTHERMIC DECOMPOSITION REACTIONS

A violent explosion occurred during routine recovery of wet trichloroethylene by distillation at ambient pressure. This was attributed to hydrolytic formation of hydrochloric acid and concentration of the latter, leading to corrosion and blocking of the vent line which caused pressure development and a consequential increase in distillation temperature of the vessel contents. The corrosion products may have catalysed the exothermic decomposition reaction which led to explosion. The vessel contained much carbonised residue. 

As well as the normal addition reaction, an extremely exothermic decomposition reaction may occur, particularly at high vessel loadings. At loadings of 0.8 ml of 1 1 mixture per ml, the violent reaction, catalysed by iron(III) chloride, initiates at —40°C and will attain pressures above 0.7 kbar at the rate of 14 kbar/s. At 0.5 ml loading density, a maximum pressure of 68 bar, attained at 114 bar/s, was observed. 

The self-heating and decomposition of the explosive and aqueous alkali was studied by DSC in a sealed capsule and in a larger scale furnace test. A rapid exothermic decomposition reaction can be initiated at 100°C or below, and may lead to spontaneous ignition and then deflagration or detonation. 

The dry salt was more or less explosive, depending on the method of preparation [1], DTA examination of a 15% solution of the diazonium salt in hydrochloric acid showed an exothermic decomposition reaction with the exotherm peak at 65°C. Adiabatic decompositon of the solution at 20° C took 80 min to attain the maximum... 

The most exothermic decomposition reaction of hydrazine would be... 

When AN particles are mixed with GAP, AN-GAP composite propellants are formulated. The specific impulse is increased by approximately 10 s by replacing PB or PU binder with GAP, as shown in Fig. 4.16. The burning rate is also increased due to the exothermic decomposition of GAP. Since GAP burns by itself, the burning of the AN particles is supported by the exothermic decomposition reaction of the GAP at the burning surface of the propellant. As shown in Fig. 7.61, the burning rate is drastically decreased by the addition of AN particles. When is in-... 

When high-intensity radiative energy is supplied to the surface of an energetic material, the surface absorbs the heat and its temperature increases. If the energetic material is optically translucent, part of the radiation energy penetrates into the interior of the propellant, where it is absorbed. When the surface reaches its decomposition temperature, reactive gaseous materials are formed on and above the surface through an endothermic or exothermic decomposition reaction. i-2 When the reaction in the gas phase is estabUshed and the temperature is increased... 

CHEMICAL STABILITY/REACTIVITY ASSESSMENT COMPUTATION OP REACTIVE CHEMICAL HAZARDS EXOTHERMIC DECOMPOSITION REACTIONS... 

Process safety evaluations of the exchange reaction on aryl iodides using i-PrMgCl revealed the danger of a highly exothermic decomposition reaction at elevated temperatures (>80°C). ... 

CautionI The washing procedure described in Note 8 should be followed carefully. On one occasion, allowing a contact time ofca. 1 hr while attempting to use a cannula filter to remove the methylene chloride led to an exothermic decomposition reaction. 

Addition of chloride ions (as solid calcium chloride, potassium chloride or sodium chloride) to aqueous solutions containing 40% of peroxyacetic acid and 1 % of acetic acid leads to a violently exothermic decomposition reaction. Chlorine is evolved, most of the liquid evaporates and the residue (often red coloured) deflagrates. 

See ASSESSMENT OF REACTIVE CHEMICAL HAZARDS, COMPUTATION OF REACTIVE CHEMICAL HAZARDS, EXOTHERMIC DECOMPOSITION REACTIONS, OXYGEN BALANCE, THERMOCHEMISTRY AND EXOTHERMIC DECOMPOSITION... 

Ethoxyethynyl alcohols, 129 Exothermic decomposition reactions, 130 Exothermicity, 130... 

Incidentally, the effect of the concentration of a chemical of the TD type on the rate of the exothermic decomposition reaction, in the early stages of the selfheating process, of the chemical is assumed to be of the zeroth order in the thermal explosion theory [1], In other words, it is assumed in the thermal explosion theory that the concentration of the chemical remains virtually constant while the self-heating process is in the early stages, because the consumption of the chemical caused by the reaction can be neglected while the self-heating process is in the early stages. 

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