METHOD OF PRODUCING BIODIESEL FUEL Russian patent published in 2011 - IPC C11C3/04 

FIELD: chemistry.

SUBSTANCE: rape-seed oil is treated with ethyl alcohol through re-esterification in volume ratio 0.5-1.0:10-15 until achieving homogeneous state. The obtained mixture is fed into a reactor in which re-esterification takes place at temperature 250-280°C, pressure 15-20 MPa, for 5-10 minutes. The mixture is cooled and then fed into an extractor. The mixture is the extracted with carbon dioxide in supercritical conditions with carbon dioxide flow rate of 20-35 l/h, temperature 240-260°C and pressure 15-20 MPa. The obtained homogeneous mixture is fed into a first separator for separation of glycerine from the end product at pressure 0.5 MPa and temperature 20-30°C. The end product is fed into a second separator for separation of fatty acid ethyl alcohol from carbon dioxide at pressure 0.2-0.3 MPa and temperature 5-10°C. The end product is fed into the second separator for separation of carbon dioxide at pressure 0.1-0.15 MPa and temperature 10-20°C. Carbon dioxide separated in the second separator is preferably recycled.

EFFECT: simple process.

2 cl, 1 tbl, 2 ex