Ignition of nitromethane

In this section, we apply this theoretical approach to study the chemistry of nitromethane ignition and detonation. This problem is considered zero-dimensional since it does not involve any spatial dimensions for mass and energy diffusion. We begin our example by studying the ignition of nitromethane under constant volume. The governing equations are ... 

Fig. 1. Temperature and major species concentration (mole fraction) profiles as a function of time for the ignition of nitromethane in a shock tube. Starting conditions were 1202 K and 6.85 atm.

Fig. 2. Reaction mechanism diagrams for the carbon-containing and nitrogen-containing species during the ignition of nitromethane. Starting conditions are 1202 K and 6.85 atm. Unimolecular decomposition is indicated by the third-body notation +M. Thick arrows indicate major reaction pathways.

Dining preparations to initiate the explosion of nitromethane sensitised by addition of 20% of the diamine, accidental contact of the liquid mixture with the solid tetryT detonator caused ignition of the latter. 

Among other compounds, methyl nitrate, nitromethane, ethyl nitrate and tetrafluo-rohydrazine function as promoters of spontaneous ignition of mixtures of methane or propane with oxygen and argon. 

Contact with metal oxides increases the sensitivity of nitromethane, nitroethane and 1-nitropropane to heat (and of nitromethane to detonation). Twenty-four oxides were examined in a simple quantitative test, and a mechanism was proposed. Cobalt, nickel, chromium, lead and silver oxides were the most effective in lowering ignition temperatures [1]. At 39 bar initial pressure, the catalytic decomposition by chromium or iron oxides becomes explosive at above 245° C [2],... 

Hydrogen Sulfide. Ignition occurs on contact of the gas with the metal oxide.15 Metals. Potassium reacts explosively and magnesium violently.16 Nitroalkanes. Ignition temperature of nitromethane, nitroethane, and 1-nitropropane, and sensitivity of nitromethane to detonation lowered by contact with lead oxide.17... 

Chlorides. Contact of 75% phosphoric acid containing traces of chlorides within a closed storage tank may liberate hydrogen, which will explode on ignition.3 4 Nitromethane. Mixtures of nitromethane and phosphoric acid can be detonated.5 Sodium Borohydride. Generation of diborane by addition of sodium borohydride to anhydrous phosphoric acid may be dangerously violent.6... 

Incompatible with aliphatic amines, alkanolamines, alkylene oxides, amides, organic anhydrides, epichlorohydrin, isocyanates, vinyl acetate. Increases the explosive sensitivity of nitromethane. Attacks most forms of metals, plastics, mbber and coatings and may cause spontaneous ignition. A confirmed human carcinogen. 

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