Liquid surface tension, kinematic viscosity, density and refractive index of the binary mixtures of n-hexadecane with methyl butyrate and methyl decanoate close to saturation conditions

Abstract

To facilitate the application of clean alternative fuels or fuel additives in compression ignition engines and a better understanding of the characteristics of their combustion and emission, physical biofuel surrogates are necessary to be proposed in computation and the knowledge of their thermophysical properties, such as liquid density, surface tension and viscosity, are also crucial for the design and optimization of the fuel injection system. Therefore, the surface light scattering (SLS) method was adopted for the simultaneous determination of the liquid surface tension and kinematic viscosity of the binary mixtures containing n-hexadecane, methyl butyrate and methyl decanoate in the temperature range between (353.15 and 423.15) K in the present work. Additionally, a U-tube densimeter and refractometer were used to obtain the liquid density and refractive index of the binary mixtures in the temperature range from (293.15–423.15) K and (293.15–358.15) K, respectively. Correlations for all thermophysical properties against temperature and mole fraction were also proposed. The relative deviations of liquid density, refractive index, kinematic viscosity as well as surface tension data from those calculated by the proposed equations were within ±0.3%, ±0.20%, ±2% and ±1%, respectively for the binary systems.