METHOD FOR DETERMINING CHANGE IN QUALITY CHARACTERISTICS OF DIESEL FUELS WHEN INTERACTING WITH ANTICORROSION COATINGS UNDER STORAGE CONDITIONS Russian patent published in 2025 - IPC G01N33/22 G01N17/00 

FIELD: measuring.

SUBSTANCE: invention relates to a method for determining change in the qualitative characteristics of diesel fuels when interacting with anticorrosion coatings under storage conditions for up to 5 years, comprising dividing a sample of the test diesel fuel into five samples of not more than 1.0 dm³ each, determination of the following physical and chemical properties for the first sample: acidity, oxidative stability (total amount of sediment), concentration of actual resins, iodine number, optical density at wave length 400 nm, placing remaining samples of diesel fuel into sealed vessels made of inert material, immersion into the second and third samples of steel plates with dimensions of 150×70×4 mm, on which the investigated anticorrosion coating with a protected edge is applied, exposure of the second, third, fourth and fifth samples to accelerated aging in a climatic chamber at temperature of 60 °C, holding for anticorrosion coatings of normal type in a climatic chamber for 1080 h, reinforced type – 1440 h, especially reinforced type – 1800 h, extraction of samples after holding in a climatic chamber and settling for 24 hours, determination for the second, third, fourth and fifth fuel samples of the same physical and chemical parameters as for the first sample, evaluation of the test results by comparing the differences of the averaged values of the indicators after the accelerated aging of the second and third samples and the values of the corresponding indicators of the first sample with the differences of the averaged values of the indicators after the accelerated aging of the fourth and fifth samples and the values of the corresponding indicators of the first sample, wherein the anti-corrosion coating is considered not to have passed the test and is not suitable for use as an anti-corrosion coating for storage facilities for diesel fuels for up to 5 years, if changes in indicators after accelerated aging of the second and third samples compared to changes in values of indicators after accelerated aging of the fourth and fifth samples exceed the following values for: acidity – 2.0 mg KOH/100 cm³ of fuel; oxidative stability (total amount of sediment) – 15 g/m³ of fuel; concentration of actual resins – 2.0 mg/100 cm³ of fuel; iodine number – 0.5 g I/100 g of fuel; optical density at wave length 400 nm – 0.5 B.

EFFECT: use of the proposed invention enables to determine the possibility of the effect of the anticorrosive coating of storage facilities on diesel fuel under storage conditions for up to 5 years.

1 cl, 1 dwg, 2 tbl, 1 ex