Changes of Some Physicochemical Properties of Canola Oil by Adding n-Hexane and Ethanol Regarding Its Application as Diesel Fuel

Canola oil cannot be directly used as a fuel in diesel engines because its physicochemical properties differ considerably from those of diesel oil. Therefore, the studies were intended to make closer the surface tension, viscosity and density of the canola oil to those of diesel fuel by adding n-hexane and ethanol. The surface tension and its components as well as density and viscosity were determined not only for the canola oil mixtures with n-hexane and ethanol but also for the canola oil components. The surface tension components were determined based on the contact angle measurements on PTFE. To obtain the components and parameters of saturated fatty acids, the contact angles of water, diiodomethane and formamide on their layers were measured. The contact angles of the studied mixtures were also measured on the engine valve. The obtained results and theoretical considerations allowed us to explain why the values of the surface tension, density and viscosity of canola oil are higher than those for its components. They also contributed to the explanation of the mechanism of the reduction in these quantities for canola oil by the addition of n-hexane and ethanol. It appeared, for example, that viscosity of the canola oil mixture with 20% n-hexane contacted with ethanol is close to that of diesel fuel.

Automated summary

Canola oil cannot be used as diesel fuel directly due to significant differences in its physicochemical properties. To address this issue, researchers added n-hexane and ethanol to the canola oil to adjust its surface tension, viscosity, and density to be closer to diesel fuel. Measurements were taken on the surface tension, density, and viscosity of the canola oil mixtures with n-hexane and ethanol, as well as the individual components of canola oil. The results provided an explanation for the higher values of surface tension, density, and viscosity in canola oil compared to its components, and revealed the mechanism behind the reduction of these properties when n-hexane and ethanol were added. For instance, a canola oil mixture with 20% n-hexane and ethanol exhibited a viscosity similar to diesel fuel.