Evaluation of the Physicochemical Authenticity of Aviation Kerosene Surrogate Mixtures. Part 2: Analysis and Prediction of Thermophysical Properties

In part 1 (10.1021/ef100496j) of this series of two papers, we presented an evaluation strategy that can be applied to surrogate mixtures for finished fuels. This strategy uses the advanced distillation curve approach to evaluate the surrogate in terms of physicochemical authenticity or how well the surrogate represents the chemical and physical properties of the finished fuel. While this protocol can be applied to any surrogate family, of particular interest here are surrogates for Jet-A/JP-8. The volatility was studied in detail as described in part 1(10.1021/ef100496j), whereas here, we focus on density, speed of sound, and viscosity. We calculated these properties for the common Jet-A/JP-8 surrogates and Jet-A, with the National Institute of Standards and Technology (NIST) REFPROP program (which incorporates equations of state and a transport property model). We then used REFPROP as a surrogate mixture design tool and developed a simple, three-component surrogate mixture (n-dodecane, n-tetradecane, and 1,2,4-trimethylbenzene with mass fractions of 0.31, 0.38, and 0.31, respectively). This mixture was subsequently formulated in the laboratory and measured with the advanced distillation curve approach. We found the agreement with the theory to be excellent (within 1.5 degrees C), and we also found that the ability of such a simple mixture to represent Jet-A/JP-8 was also excellent. Comparisons made to the calculated density, speed of sound, and viscosity were also excellent.