Comparison of physical and chemical properties of crude coldpressed vegetable oils used to drive agricultural tractors

Crude vegetable oil may be used to drive self-ignition engines adjusted to this fuel. The aim of this study was to perform a comparative analysis of selected properties of cold-pressed crude vegetable oils used as biofuels. Physico-chemical properties of rapeseed oil (RO), sunflower oil (SO) and corn oil (CO) were compared. Density, kinematic viscosity, flash point, cold filter plugging point, calorific value, content of water, phosphorus, calcium and magnesium in oil were determined. Kinematic viscosity curves of crude oils at temperatures from 5°C to 50°C were defined. The kinematic viscosity was the lowest for corn oil and the highest for sunflower oil.