Densities, Viscosities, Speeds of Sound, Bulk Moduli, Surface Tensions, and Flash Points of Quaternary Mixtures of n-Dodecane (1), n-Butylcyclohexane (2), n-Butylbenzene (3), and 2,2,4,4,6,8,8-Heptamethylnonane (4) at 0.1 MPa as Potential Surrogate Mixtures for Military Jet Fuel, JP-5

摘要

The composition of Navy Jet fuel JP-5 was determined using gas chromatography(GC)-electron impact mass spectrometry and GC x GC/(flame ionization detection) to contain by mass 21% linear alkanes, 29% cycloalkanes, 32% isoalkanes, and 18% aromatic compounds. Various quaternary mixtures of n-dodecane, n-butylcyclohexane, n-butylbenzene, and 2,2,4,4,6,8,8-heptamethylnonane were prepared as possible surrogates for this jet fuel and analyzed for density and viscosity (253 to 333) K, speed of sound (288 to 333) K, surface tension (294 +/- 1 K), and flashpoint. Deviation cutoffs for "matching" the JP-5 based on previous studies and fuel specification were +/- 1.7% for density, +/- 1% for speed of sound, +/- 3.5% for bulk modulus, +/- 2.6% for viscosity, +/- 2.2% for surface tension, and +/- 10% for flash point (minimum of 333 K). Seven quaternary mixtures met these cutoffs. Three had compositions that were comparable to the JP-5 and would be good candidates for engine testing. All mixture excess molar volumes showed a trend of increasing to a maximum and then decreasing as the concentration of n-butylbenzene increased. Viscosity deviations ranged from (-0.03 to -0.48) mPa.s.