Propellants nitrogen

Propellants. The propellant, said to be the heart of an aerosol system, maintains a suitable pressure within the container and expels the product once the valve is opened. Propellants may be either a Hquefied halocarbon, hydrocarbon, or halocarbon—hydrocarbon blend, or a compressed gas such as carbon dioxide (qv), nitrogen (qv), or nitrous oxide. 

Compressed gas systems were originally developed simply to provide a means of expelling a product from its container when the valve was depressed. SemisoHd products such as a cream, ointment, or caulking compound are dispensed as such. A Hquid concentrate and a compressed gas propellant (Fig. 3) produce a spray when a mechanical breakup actuator is used. Nitrogen, insoluble in most materials, is generally used as the propellant. 

R. E. Anderson, E. M. Vander Wall, and R. K. Schaplowsky, "Nitrogen Triduoride," USjW Propellant Handbook AE RPT-T -ll-11 Contract E04611-76-C-0058, Aerojet Liquid Rocket Co., Sacramento, Calif., 1977. 

Group 15 (VA) Perchlorates. Nitrogen perchlorates have been used as oxidizers in rocket propellants. Hydrazine perchlorate [13762-80-6] NH2NH2CIO4, and hydrazine diperchlorate, CIO4NH2NH2CIO4, have been investigated as oxidizers for propellant systems (60). Anhydrous salts can be... 

In explosives, diphenylamine stabilizes cellulose nitrate by reacting with nitrogen oxides (see Explosives and propellants). The products formed include /V-nitrosodiphenylamine and mono andpolynitro derivatives. 

Industrial. Nitric acid is itself the starting material for ammonium nitrate, nitroglycerin [55-63-0] trinitrotoluene [118-96-7]., nitroceUulose [9004-70-0] and other nitrogen compounds used in the manufacture of explosives (see Explosives and propellants). Nitric acid is made by oxidation of ammonia to nitrogen dioxide [10102-44-0] which is subsequently absorbed by water. 

Sodium nitrate is used as a fertiliser and in a number of industrial processes. In the period from 1880—1910 it accounted for 60% of the world fertiliser nitrogen production. In the 1990s sodium nitrate accounts for 0.1% of the world fertiliser nitrogen production, and is used for some specific crops and soil conditions. This decline has resulted from an enormous growth in fertiliser manufacture and an increased use of less expensive nitrogen fertilisers (qv) produced from synthetic ammonia (qv), such as urea (qv), ammonium nitrate, ammonium phosphates, ammonium sulfate, and ammonia itself (see Ammonium compounds). The commercial production of synthetic ammonia began in 1921, soon after the end of World War I. The main industrial market for sodium nitrate was at first the manufacture of nitric acid (qv) and explosives (see Explosives and propellants). As of the mid-1990s sodium nitrate was used in the production of some explosives and in a number of industrial areas. 

In 1887, Nobel invented Ballistite composed of 40% low nitrogen nitrocellulose and bOPi nitroglycerin. Cut into flakes, it was a good propellant. The British ignored his patcni and developed a similar product called cordite. ... 

Perhaps the best known oxide of nitrogen is N20, commonly called nitrous oxide or laughing gas. Nitrous oxide is frequently used as an anesthetic, particularly in dentistry. It is also the propellant gas used in whipped cream containers N20 is nontoxic, virtually tasteless, and quite soluble in vegetable oils. The N20 molecule, like all those in Figure 21.6, can be represented as a resonance hybrid. 

The evolution of nitrogen aids in removing dissolved air. A salt bridge (4 mm tube) attached to the saturated calomel electrode is filled with 3 per cent agar gel saturated with potassium chloride and its tip is placed within 1 mm of the mercury cathode when the mercury is not being stirred this ensures that the tip trails in the mercury surface when the latter is stirred. It is essential that the mercury-solution interface (not merely the solution) be vigorously stirred, and for this purpose the propeller blades of the glass stirrer are partially immersed in the mercury. 

Other Uses of Nitric Acid. As mentioned earlier, fuming nitric acid (FNA) when mixed with ale, toluene or acet anhydr will cause an expln. However, there are many other uses for FNA in energetic materials technology. As either red fuming nitric acid (RFNA) or as nitrogen tetrox-ide, it is used extensively as the oxidizer in pro-pint systemsnfor ram-jets, jet motors, space rockets and other missiles (Refs 37, 38 39). See also under Liquid Propellants in Vol 7, L24-Rff... 

Wilkniss, Fast Neutron Activation Analysis For Nitrogen in Explosives and Propellants , RadiochimActa 7 (4), 196—8 (1967) CA 68, 4570 (1968) 45) Anon, Fropeilant,... 

Nitrogen Oxides as Rocket Fuel Oxidants Including The Theoretical Performances of Propellant Systems Employing Nitrogen Tetroxide , JPL PR No 9-23, Cal Inst Tech, Proj No TU2-1,... 

For additional information on Nitrogen tetroxide, see under Liquid Propellants in Vol... 

L34-R to L44-R Hypergolic Propellants in Vol 7, H254-L to H259-R Nitrogen Determination in Energetic Materials, and Mass Spectrometry in this Vol... 

Pollard s Test for Stability of Propellants. This test, proposed in 1924—25, is based upon the action of nitric peroxide on colloidal Ag oxide Procedure. A current of air is passed over a sample of proplnt in storage into a colloidal soln of Ag oxide. If free nitrogen peroxide is present, it reacts with the colloid and decreases the amt of light diffused by it. The larger the decrease, the higher the amt of N02 present, and the more decompd is the proplnt Ref Reilly (1938), 80... 

Fig. 7. Best-fit agreement between experimental and calculated ignition data for PBAA/AN composite propellant (P8). Key O, pure-oxidizer environment A, oxidizer-nitrogen environment at 55 psia total pressure.

Ever) year our planet is bombarded with enough energy from the Sun to destroy all life. Only the ozone in the stratosphere protects us from that onslaught. The ozone, though, is threatened by modern life styles. Chemicals used as coolants and propellants, such as chlorofluorocarbons (CFCs), and the nitrogen oxides in jet exhausts, have been found to create holes in Earth s protective ozone layer. Because they act as catalysts, even small amounts of these chemicals can cause large changes in the vast reaches of the stratosphere. 

Iridium Coating for Spacecraft Rocket Nozzles. The coating of rocket nozzles with iridium is a good example of the ability of CVD to provide a complete composite material, in this case a structural refractory shell substrate coated with a corrosion- and oxidation-resistant component. The device is a thruster rocket nozzle for a satellite. The rocket uses a liquid propellant which is a mixture of nitrogen tetroxide and monomethyl hydrazine. 

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