Oxygenate

Catalysis

Engineering

Reactivity (psychology)

Boron

Materials science

Hydrogen peroxide

Propellant

Ammonia borane

Chemical engineering

Hydrogen storage

Alternative medicine

Thermodynamics

Hydrogen

Physics

Organic chemistry

Combustion

Medicine

Chemistry

Ionic liquid

Ignition system

Pathology

Fuel

Exploring novel green hypergolic fuels ignited with hydrogen peroxide (H2O2) offers a number of opportunities in space propulsion with regard to replacing conventional toxic propellant combinations. The green hypergolic fuels, BH bond-rich zwitterions and ionic liquids (ILs) were synthesized; their hypergolic reactivity was investigated with 95% H2O2. Remarkably, ammonia borane (AB) and 1-ethyl-3-methyl imidazolium borohydride ([EMIM][BH4]) exhibited the lowest ignition delay times of 8.1 and 18.5 ms, respectively. For a comprehensive application, the reactivity of liquid and hybrid fuel blends were studied. A liquid fuel blend, [EMIM][BH4] and methyl imidazolium borane (MIMB) (1:1, w/w) exhibited the ignition delay time of about 35 ms. Further, a solid hybrid fuel blend consisting of 40% AB-paraffin revealed a hypergolic ignition delay time of 9.2 ms. Additionally, the gas phase heat of formation and specific impulse were calculated using G09 and NASA-CEC-71 programs, respectively. The specific impulse of AB was 273 s, which is higher than the stated hypergolic zwitterions. Hence, the BH bond-rich zwitterions and ILs are promising choices for new generation green hypergolic liquid and hybrid rocket propulsion.

Ignition of boron-based green hypergolic fuels with hydrogen peroxide