As a product of a centuries-old physico-chemical transformation of natural organic elements in the bowels of the earth, oil is characterized by an unusually rich composition of inter-soluble chemical compounds. The main ones are paraffins, naphthenes and aromatics. Their ratio depends on the oil field and determines the direction of further processing of oil: fuel, oil or fuel-oil.
The second most important characteristic of oil is its fractional composition, which determines the properties of not only the oil itself, but also the products derived from it.
The chemical composition of the oil components is not only hydrocarbons, but also sulfur and nitrogenous compounds, asphalt-resinous substances, compounds with heavy metals content. The main compounds determining the corrosive properties of oil and its products are sulfur compounds.
The main characteristic of gasoline, which determines their combustion in ICE without detonation is the octane number, and for diesel fuels - cetane number.
The most important characteristics of petroleum products are the flash point, as well as the calorific value. To establish the possibility of storage, pumping and use of petroleum products in the winter, in the Arctic and at high altitudes, it is necessary to determine their low-temperature indices, as well as viscosity.
The use of petroleum products at various temperatures is associated with significant viscosity changes and corresponding significant fluctuations in the cost of pumping.
Storage of petroleum products in contact with air leads to their oxidation, darkening, moistening, accumulation of asphalt-resinous compounds. Therefore, it is necessary to monitor the change in the quality of petroleum products during storage.
The use of petroleum products leads to certain negative consequences for the environment. To assess these effects, pollution control devices are used.