Rocket propulsion oxidizers

Rocket propulsion oxidizers, 18 384-385 Rocks, weathering of, radiation and, 3 299 Rocksalt, crystal structure of, 2 6, 29 Rock-salt-type alkali halide crystals, dissolution process, 39 411 19 alkali chlorides, 39 413, 416 alkali fluorides, 39 413-415... 

Composite proplnts, which are used almost entirely in rocket propulsion, normally contain a solid phase oxidizer combined with a polymeric fuel binder with a -CH2—CH2— structure. Practically speaking AP is the only oxidizer which has achieved high volume production, although ammonium nitrate (AN) has limited special uses such as in gas generators. Other oxidizers which have been studied more or less as curiosities include hydrazinium nitrate, nitronium perchlorate, lithium perchlorate, lithium nitrate, potassium perchlorate and others. Among binders, the most used are polyurethanes, polybutadiene/acrylonitrile/acrylic acid terpolymers and hydroxy-terminated polybutadienes... 

All of the theoretically possible high-energy (and potentially hazardous) oxidant-fuel systems have been considered for use, and many have been evaluated, in rocket propulsion systems (with apparently the sole exception of the most potent combination, liquid ozone-liquid acetylene). Some of the materials which have been examined are listed below, and it is apparent that any preparative reactions deliberately involving oxidant-fuel pairs must be conducted under controlled conditions with appropriate precautions to limit the rate of energy release. 

Mixtures of CIF3O and CIF5 (225) hold promise as an oxidizer in rocket propulsion. 

Blends of perchloryl fluoride with halogen fluorides are homogeneous and stable. When these are used as storable liquid oxidizers for rocket propulsion, the halogen fluoride usually confers hypergolicity, increased density, and lowered vapor pressure whereas the perchloryl fluoride provides oxygen needed for efficient combustion of carbon in the fuel or of certain metal additives. The mixtures are thermally stable and their... 

Aluminium particles are made with diameters in the range of 20 to 200 nm, with a protective shell of aluminium oxide about 4 nm thick and, mixed with a suitable oxidising agent, are used for rocket propulsion fuels. 

Aliphatic hydrocarbons petrol, paraffin. In the U.S.A. several types of combustibles for liquid propellant jet aircraft are used. One of them, i.e. JP-4, is employed for rocket propulsion, with nitric acid as an oxidizing agent (it can also be used with hydrogen peroxide or liquid oxygen). The specification of JP-4, is as follows ... 

Clearly, attempts to increase the energy liberated by liquid mixtures for rocket propulsion are based, in the first instance, on the use of those components (combustible and oxidant) which release as much heat as possible. E.g. the use of ozone as an oxidant has been discussed above (p. 309). 

Due both to its simplicity and to its practical importance, hydrogen has attracted extensive research as a fuel. Hydrogen is an important fuel in rocket propulsion, and may in the future, due to the increasing concern with CO2 emissions, replace hydrocarbon fuels in some energy conversion processes. Furthermore the hydrogen/oxygen subset is important in the oxidation of all hydrocarbons. 

High-temperature conditions such as those occurring in gas turbines or rocket propulsion units present severe conditions of operation to any metallic component. In such conditions, the hot gases attack the metal surface causing oxide formation (in the case of oxygen attack). In order for the metal to be serviceable under these conditions, oxidation must cease immediately a thin adherent film has formed on the metal surface, i.e. the film is protective. What factors govern the rate of scale formation in metal/hot gas reactions ... 

All technical processes for the synthesis of hydrazine yield either hydrazine in aqueous solution or hydrazine hydrate. Most applications can use hydrazine hydrate, but for some applications, for example, rocket propulsion, anhydrous hydrazine is necessary. The water can be removed by a chemical reaction followed by distillation or by azeotropic distillation with an auxiliary fluid. As water binding chemicals, calcium carbide, sodium hydroxide, calcium oxide, calcium hydride, barium oxide, barium hydroxide, and barium pemitride Ba3N4 have been used. The use of sodium or calcium metal and sodium amide is best avoided because of the formation of explosive hydrazides. Starting from hydrazine hydrate (64% hydrazine), sodium hydroxide is generally used... 

Used in the nitration of organic compounds and explosives, in the manufacture of oxidized cellulose compounds, and as an oxidizing agent in rocket propulsion. It is an intermediate in the production of nitric and sulfuric acids. 

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