PROCESS FOR PREPARING AN OIL WITH HIGH CONTENT OF POLYUNSATURATED FATTY ACIDS AND A DIESEL BIOFUEL

摘要

The invention relates to a process for preparing an oil having a high content of polyunsaturated fatty acids combined as triglycerides and a Diesel biofuel. According to the invention, the process consists in dehydrating the fish oil up to a maximum water content of 0.05%, treating it with 0.9...1.15% alkaline catalyst dissolved in 19.15...32.1% methanol or ethanol, the reaction mass being then maintained at the temperature of 65...90°C for 60...90 min while stirring, raw glycerine being separated by settling from the raw alkyl esters, wherefrom alcohol is separated by distillation, the alkyl esters are further successively separated by rectification to obtain the distillate 1 and the residue 1, then the distillate 2 and the residue 2, the distillate 1 is mixed with the distillate 2 to form a Diesel biofuel, while the residue 2 is treated with glycerine at a molar ratio of 1:2.3...2.4, with 0.85%...1.05% alkaline catalyst, at a temperature of 125...135°C, for 6...8 h, at a pressure of 25...30 mbar, wherefrom an alcohol condensate is separated by distillation, the resulting raw triglycerides being washed with alcoholic solutions, water and volatile matter being eliminated by distillation to finally result in an oil having a high content of unsaturated fatty acids which is treated with activated carbon and filtered.