Diborane Fuels

Liquefied petroleum gas fuel, air-inh. engines Diborane fuel, airplane... 

Other boron hydrides are known, most of them having the general formula B H + 4- for example pentaborane, B5H9, decaborane, BjqHi4. Each can be made by heating diborane in suitable conditions for example at 420 K, decaborane is obtained. Boron hydrides have been tried as rocket fuels. 

L.4 The compound diborane, B2H6, was at one time considered for use as a rocket fuel. Its combustion reaction is... 

The fact that HBO, a reactive compound, was produced rather than the relatively inert B203 was a factor in the discontinuation of the investigation of diborane as a fuel. 

Fluorine Diborane 5.0 — 291 Fuels most commonly used... 

Diborane. Se. Vol 2, p B253-R, under Boron Hydrides and p B255-L, under Boron Hydride Fuels. See also the following addnl Refs ... 

In general, the stable thermodynamic products of ordinary flames have little worth, but many of the uncommon flames have products of value. The chlorination of hydrocarbons may be carried out in a flame process which was recently announced (A4). A most fascinating example is the formation of boron nitride from the flame reaction between diborane and hydrazine, two compounds which are ordinarily thought of as fuels (B2, VI). The stabilization of this flame depends upon the proper preparation of the premixed gases, since a solid adduct between the reactants prevents flame stabilization if the preflame residence time is too great. 

The fact that HB02, a reactive compound, was produced rather than the relatively inert B203 was a factor in the discontinuation of the investigation of diborane as a fuel, (a) What mass of liquid oxygen (LOX) would be needed to burn 50.0 g of B2H6 (b) Determine the mass of HB02 produced from the combustion of... 

Pentaborane(9), generated some time ago on a pilot plant scale via diborane pyrolysis as part of the fuel development program mentioned above, is currently stockpiled in large quantity by the U.S. Government. A convenient laboratory-scale preparation utilizes the bromotriborohydride anion ... 

Diborane (B2H6) is a highly reactive boron hydride, which was once considered as a possible rocket fuel for the U.S. space program. Calculate AH for the synthesis of diborane from its elements, according to the equation... 

Diborane. Se. Vol 2, p B253-R, under Boron Hydrides and p B255-L, under Boron Hydride Fuels. See also the following addnl Refs Refs 1) F.R. Price, JACS 72, 5361-65 (1950) 8e CA 45, 2755(1951)(First 8e 2nd pressure limits of espln of Diborane-Oxygen tnixts) 2) R.P. Clarke R.N. Pease, JACS 73, 2132-34(1951) 8s CA 45, 7418(1951) (Kinetics of pyrolysis of Diborane) 3) J-K-Bragg et al, JACS 73, 2134-40(1951) 8s CA 45, 7418(l951)(Kinetics of pyrolysis of Diborane) 4) A.T. Whatley 8s R.N. Pease, JACS 76, 1997-99(1954) 8s CA 48. 8543(1954) (Thermal expln of Diborane-oxygen mixts)... 

Diborane is valued as a fuel for use in rocket propellants. Gallery Ghemical Co. developed equipment and procedures for the safe handling of diborane and by 1962 had produced about 5 million pounds of the material. It is offered for shipment in chrome-molybdenum steel cylinders at —80° (minimum order 100 g.), and technical bulletins present information on handling procedures and safety precautions. 

Following the introduction of the boron hydrides in the 1940s as rocket fuels, the neurotoxic properties of diborane, pentaborane, and decaborane became known (Yarbrough et al. 1985). Diborane, a gas, produces mostly pulmonary symptoms. Pentaborane, a liquid, and decaborane, a solid, cause severe cardiac and neurological damage. 

There are many advantages to the use of NH3 as hydrogen source for vehicular fuel cell vehicle applications. However, a major drawback is ammonia s extreme toxicity and adverse health effects. By complexing NH3 with diborane, a stable, non-toxic and non-cryogenic material (H3BNH3) can be prepared. This ammonia-borane complex is stable in water and ambient air and when heated liberates H2 in a sequence of reactions between 137°C and 400°C that reaches about 20% of the initial mass of H3BNH3. Successfiil implementation of ammonia-borane as a potential future transportation fuel, however, requires new chemical techniques and/or processes for its s mthesis that promise substantial reduction in its production costs. 

EXPLOSION and FIRE CONCERNS nonflammable gas, but strong oxidizer NFPA rating Health 4, Flammability 0, Reactivity 0 reacts explosively with acetylene, ether, turpentine, ammonia, fuel gas, hydrogen, and finely divided metals reacts violently with many alcohols explodes on contact with molten aluminum, ammonia, benzene, bromine pentafluoride, diborane, and many others combines with moisture to form reactive hydrogen chloride gas use water spray or fog for firefighting purposes. 

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