Study on Al NPs-containing suspension as high-density liquid fuel

Aluminum particles have been used as an additive of high density and energy to improve the energy of fuel and propellant. Here the possibility of preparing suspension fuel was studied by modifying the surface of Al nanoparticles (NPs) and adding them into liquid fuel. Trioctylphosphine oxide (TOPO) was used as the surfactant to modify the NP surface, and the particle structure and dispersion stability, as well as the density, energy and viscosity of suspension fuel were analyzed. It is found that the surface modification could inhibit the agglomeration and settlement of NPs, and made them disperse stably in liquid hydrocarbon fuel like HD-03 for a relatively long time. The density and volumetric energy of the fuel increased significantly, and it could flow freely like common liquid fuel. With 10wt% and 30wt% NPs added, the density, volumetric energy and viscosity of the fuel were 1.06 g/mL and 1.14 g/mL, 44.3 MJ/L and 45.4 MJ/L, 80 mPa·s and 2000 mPa·s, respectively.