METHOD TO DERIVE LOW MOLECULAR WEIGHT OLEFINS FROM LIGHT HYDROCARBON MATERIAL Russian patent published in 2008 - IPC C10G9/14 

FIELD: chemistry.

SUBSTANCE: invention relates to the method of low molecular weight olefins deriving, including pre-ward thermal pyrolysis of gasoline cut in warm pipes of tube heater with hydrocarbon product and amorphous coke derivation followed by thermal pyrolysis light hydrocarbon material in the same worm pipes of the tube heater. Furthermore, pre-ward thermal pyrolysis of gasoline cut is carried out at 760÷835°C temperature and gasoline cut mass ratio is: water vapor =1.0:0.3÷0.9 during 24÷360 hours, besides pre-ward pyrolysis of gasoline cut is carried out in 2 stages: firstly, at 760÷815°C temperature during 12÷120 hours, than at 815÷835°C temperature during 12÷240 hours, and further pyrolysis of light hydrocarbon material is carried out at 780÷855°C temperature and mass ratio of light hydrocarbon material is: water vapor =1.0:0.3÷0.9, and broad fraction of light hydrocarbon material is used as light hydrocarbon material and it has the following composition, mass fraction, %: methane - 0,01÷2,50, ethane - 0.50÷4.50, propane - 5.0÷95.00, total of C₄ - 10.00÷85.00; C₅₊ - 5.00÷35.00.

EFFECT: time is increased for heater regeneration running during thermal pyrolysis of broad fraction of light hydrocarbon with high yield of low molecular weigh olefins.

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