Borane fuels

Attempts to develop high energy borane fuels in the 1950 s... 

These data indicate that borane fuels have many props which are superior to those of JP-6. Comparison of the performance of a borane fuel with that of JP type, and using liq O as oxidizer, shows that a HEF increases the range of air-breathing engines or rockets by ca 50% over that obtd with a JP fuel in the same vehicle... 

Davis BL, Dixon DA, Garner EB, Gordon JC, Matus MH, Scott B, Stephens FH (2009) Efficient regeneration of partially spent ammonia borane fuel. Angew Chem Int Ed 48(37) 6812-6816... 

A recent useful article on this subject is by D. R. Martin (83c). However, it now appears that performance of the borane fuels has not lived up to expectation, and costs are much higher than anticipated. See Chetn. Eng. News 37, No. 36, 38 (1959). 

Hydrazine—borane compounds are made by the reaction of sodium borohydride and a hydrazine salt in THF (23,24). The mono-(N2H4 BH ) and di-(N2H4 2BH2) adducts are obtained, depending on the reaction conditions. These compounds have been suggested as rocket fuels (25) and for chemical deposition of nickel—boron alloys on nonmetallic surfaces (see Metallic COATINGS) (26). 

Decaborane is the most studied of all the polyhedral boranes and at one time (mid-1950s) was manufactured on a multitonne scale in the USA as a potential high-energy fuel. It is now obtainable in research quantities by the pyrolysis of B2H9 at 100-200°C in the presence of catalytic amounts of Lewis bases such as Me20. B10H14 is a colourless, volatile, crystalline solid (see Table 6.2, p. 163) which... 

Exotic Fuels. Accdg to Ref 1, this name is applied to high energy fuels (HEF) for jets and rockets which have higher performance rates than hydrocarbon fuels, such as kero sene or JP-6, etc. The term has also been used eo refer specifically to those jet and rocket fuels based on boron hydrides. Such fuels, known as Boranes, are described in Ref 2... 

Based on the excellent solubility and reducing properties of amine boranes, they are often used for the stabilization and purification of industrial materials. Further, they are applied as additives in hydrocarbon fuels and in lubricating oils, as polymerization catalysts, as ingredients in photographic processing and in the electroplating industry.169 High stability towards hydrolysis and oxidation makes cationic boron chelates useful as water-soluble dyes.170... 

Boron Hydrides, Derivatives and Fuels Boron Hydrides(Boranes). These constitute a group of compds which may be represented by two generic formulas BnHn + 4 and BnHn+ 6... 

Boranes as fuels compare favorably with other well established fuels in liq propellants(Ref 35) as shown in the following table ... 

Because boranes have high heats of combustion, they were once considered as potential lightweight, high-energy rocket fuels, but they proved to be too expensive to prepare. Nevertheless, boranes continue to be of interest to chemists because of their unusual structures and bonding. 

Chemistry of boron hydrides (another name, boranes) is now one of the most challenging and rapidly growing area of inorganic chemistry. Boranes are employed in many fields of man s activity, primarily as missile fuels and in cancer research. 

The boranes react very exothermically with oxygen and were once evaluated as potential fuels for rockets in the U.S. space program. 

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