Rocket propellants liquid, oxidizers

Although modern chemistry allows development of even more effective rocket propellants, energy efficiency is not the only consideration factor. For example, fluorine and its derivatives arc better oxidizers than oxygen, but their extreme toxicity make them environmentally dangerous. The same concerns prevent the use of beryllium hydride—an excellent fuel that combines high density with the energy efficiency comparable to liquid hydrogen. 

See Dichlorine oxide Dicyanogen Fluorine Halogens Oxygen (Liquid) Liquefied gases Ozone Dicyanogen ROCKET PROPELLANTS... 

Monomethylhydrazine is a clear, colorless liquid used extensively in military applications as a missile and rocket propellant, in chemical power sources, and as a solvent and chemical intermediate. Upon contact with strong oxidizers (e.g., hydrogen peroxide, nitrogen tetroxide, chlorine, fluorine) spontaneous ignition may occur. 

Eluorine nitrate (FNO ) is a strong oxidizing gas or liquid. In the liquid state it explodes by shock or friction. It is used as an oxidizer for rocket propellant fuels. 

Ducted rockets are intermediate between solid rockets and liquid ramjets in their propulsion characteristics. The propulsive force of soHd rockets is generated by the combustion of propellants composed of oxidizer and fuel components. Thus, no additional fuels or oxidizers need to be introduced from the atmosphere into the rocket motor. The momentum change of the exhaust gas from the nozzle attached to the aft-end of the combustion chamber is converted into the thrust for propulsion. On the other hand, the propulsive force of Hquid ramjets is generated by the combustion of a liquid hydrocarbon fuel with air introduced from the atmo-sphere.Ii] jjjg incoming air is compressed by a shock wave formed at the air-intake attached to the front end of the combustor. The air taken in from the atmosphere serves only as the oxidizer for the ramjets. The thrust is created by the momentum difference between the exhaust gas from the combustor and the air taken in from the atmosphere. 

Nitrosyl fluoride is an oxidizer in rocket propellants. Other apphcations are in organic synthesis where it is a fluorinating agent. The compound also is a stabdizer for liquid sulfur trioxide. 

Hybrid Rocket Propellants. A special proplnt combination of unlike materials, particularly of unlike physical characteristics. Typical hybrid proplnt combinations are a solid fuel (or oxidizer) in combination with a liquid oxidizer (or fuel) in tjiat order. Sometimes a grain of solid fuel is encased in the combustion chamber of a rocket engine and burned in combination with liq oxygen. Similarly, a liq fuel may be injected into a combustion chamber in contact with a solid oxidizer. Another example is the use of concentrated hydrogen peroxide and a hydrocarbon fuel. In this case, the hydrogen peroxide is converted by decompn into a hot gas contg oxygen. The fuel is injected downstream of the first reaction, mixed with the hot oxidizer-rich gas, and burns (Ref 1)... 

Dict (1961), 8O5-L (Mentioned as powerful oxidizer suitable for both liquid and solid rocket propellants) (1971), 857-R (Tetrafluoro-... 

In organizing the symposium, we made the usual division into solid and liquid rocket propellants. Most readers no doubt already know the relative merits of solid vs. liquid systems—viz., the instant readiness of solids (compared with cryogenic liquids), their higher density (important in volume-limited systems), and the relative simplicity of rocket construction liquids offer easy variation in thrust level and the attainment of higher specific impulses, the latter because physical separation permits the use of fuels and oxidizers that would be incompatible if premixed. 

Liquid rocket propellants are subdivided into monopropellants and bipropellants. Monopropellants are liquids which burn in the absence of external oxygen. They have comparatively low energy and specific impulse and are used in small missiles which require low thrust. Hydrazine is currently the most widely used monopropellant however, hydrogen peroxide, ethylene oxide, isopropyl nitrate and nitromethane have all been considered or used as monopropellants. Information on the performance of some monopropellants is presented in Table 8.3. 

It has been used as a solvent and as an intermediate in the manuf of chemicals used in the expl industry and of synthetic rubber (Ref 4). During WWII, acetal(as well as acetaldehyde) was used in Germany as hyper-gollic fuel in liquid rocket propellants in conjunction with red or white fuming nitric acid which served as an oxidizer. Acetal was later replaced by ca te ch o 1( Bren zc ate chin or Brenzol in Ger)(Ref 10)... 

Acetaldeiiyde(as well as acetal) was used during WVFII in Germany as a hypergolic(qvl) fuel in liquid rocket propellants in conjunction with oxidizers, red or white coned nitric acids. These fuels were later replaced by catechol(BrenzcatechoI or Brenzol, in Ger)... 

The propulsion assembly of a rocket or -> Missile. The driving force can be produced by burning liquid fuels in liquid oxidizers (liquid oxygen, nitric acid, or other oxidants such as liquid fluorine), by burning of solid propellants (-> Solid Propellant Rockets), by burning solid fuels in liquid oxidizers (-> Hybrids), or by catalytic decomposition of endothermal compounds (-> Hydrazine-, - Aerozim, - Aurol). 

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