METHOD OF DETERMINING PRESENCE OF DEPRESSOR ADDITIVE IN DIESEL FUELS Russian patent published in 2004 - IPC

FIELD: qualification test and identification of hydrocarbon fuels.

SUBSTANCE: invention relates to testing of fuels, particularly, to methods of revealing depressor additives. According to proposed method, initial fuel congelation temperature t_{c in} is determined after which sample is heated in flask with outlet tube, current temperature of vapors in flask neck is measured and heating is stopped when white vapors appear in flash neck at simultaneous drop of vapor temperature and no drops getting from flask outlet tube. Then temperature of flask with remaining fuel is reduced to room temperature, distilled part of fuel is mixed with fuel left in flask and mixture congelation temperature t_{c mix} is determined, and presence of depressor additive in sample is indicated by rise of mixture congelation temperature as compared with initial sample congelation temperature. Physical sense of mixture congelation temperature rise (mixture of distilled part of sample and fuel remaining in flask) is that depressor additive, being polymeric compound, remains in flask in process of distilling where is it decomposes (cracks) at temperatures specific foe end of distilling process (320-365^oC according to thermometer in flask neck)and, consequently, its influence stops. Invention makes it possible to detect depressor additives in diesel fuels without decreasing requirements to reliability of process.

EFFECT: reduced cost of tests.

1 ex, 1 dwg