Viscosity, Refractive Index, Deviation of Viscosity and of Refractive Index of Biodiesel plus Diesel Fuel (or Benzene) Binary Mixtures

Diesel fuel+biodiesel blends are currently commercialized as fuel for diesel engines. The liquid fuel behaviour in the internal combustion engine depends on the properties of the mixture components. Experimental viscosity and refractive index of binary biodiesel+diesel fuel and biodiesel+benzene mixtures are reported covering the whole composition range, at different temperatures from 293.15 to 323.15 K. The study was extended to biodiesel+benzene mixtures (benzene being an aromatic hydrocarbon totally miscible with biodiesel and diesel fuel respectively to better understand the behaviour of biodiesel+diesel fuel system. Viscosity data were correlated with Grunberg-Nissan one parameter equation. The values of interaction parameter (G(12)) from Grunberg-Nissan equation were found to be negative for both studied systems at all investigated temperatures. Experimental viscosity and refractive index data have been used to calculate the property deviations of biodiesel + diesel fuel and biodiesel + benzene systems, these being then correlated by the Redlich - Kister polynomial equation. It was found that for both studied systems, the deviations in viscosity and refractive index, respectively, are negative.