Petroleum products. Methods for determining fractional composition
The scope of the method consists in distilling 100 cm³ of the test sample under conditions that correspond to the nature of the product, and conducting constant observations of the thermometer readings and condensate volumes.
The interstate standard GOST 2177 establishes two methods for determining the fractional composition of petroleum products:
- Method A is suitable for motor gasolines, aviation gasolines, jet fuels for turbojet engines, set boiling point solvents, naphtha, white spirit, kerosene, gas oils, distillate liquid fuels and similar petroleum products;
- Method B – for oil and dark oil products, but if disagreements arise in assessing the quality of oil and oil products, then method A.
It should be borne in mind that high-temperature thermometers should be used for the distillation of aviation turbine fuels and other products with a wide boiling range.
Fractional composition is a defining characteristic in establishing the scope of application of petroleum products. The limits guarantee the quality of products with appropriate volatility characteristics.
The test conditions for the automated method are practically matched to the distillation conditions when using manual equipment as well as other volatility characteristics.