FIELD: chemistry.
SUBSTANCE: invention relates to hydrocracking of hydrocarbon raw materials. A method is described for hydrocracking of hydrocarbon raw materials containing at least 20 vol.%, preferably at least 80 vol.%, of compounds boiling at a temperature above 340°C. In this case, the specified method includes at least following stages: a) hydrocracking of the specified raw materials, carried out in the presence of hydrogen and at least one hydrocracking catalyst, at a temperature from 250°C to 480°C, pressure from 2 to 25 MPa, volumetric velocity from 0.1 to 6 h-1, and with such an amount of injected hydrogen that the volume ratio of a number of liters of hydrogen to a number of liters of hydrocarbon is from 100 to 2000 l/l, b) separation into gas and liquid of the flow outgoing from the stage a) to obtain a liquid flow and a gas flow containing at least hydrogen, c) direction of the gas flow containing at least hydrogen to a compression stage before its return to at least the hydrocracking stage a), d) fractionation of the liquid flow into at least one flow containing reacted hydrocarbon products having boiling points below 340°C, and an unreacted liquid fraction having a boiling point above 340°C, e) hydrocracking of the specified unreacted liquid fraction from the stage d), carried out in the presence of hydrogen and a hydrocracking catalyst with a hydrogenating function provided by at least one group VIII metal selected from iron, cobalt, nickel, ruthenium, rhodium, palladium, and platinum, and/or at least one group VIB metal selected from chromium, molybdenum, and tungsten, alone or in a mixture, and an acidic function provided by aluminosilicate or zeolites, at a temperature from 250°C to 480°C, pressure from 2 to 25 MPa, volumetric velocity from 0.1 to 6 h-1, and with such an amount of hydrogen injected that the volume ratio of liters of hydrogen to liters of hydrocarbon is from 100 to 2000 l/l, f) hydrotreatment of the flow outgoing from the stage e), mixed with liquid hydrocarbon raw materials, containing at least 95 wt.% of compounds boiling at a temperature in the range from 150°C to 400°C, the specified raw material differs from the outgoing flow from the second hydrocracking stage e), wherein the specified hydrotreatment stage f) is carried out in the presence of hydrogen and at least one hydrotreatment catalyst containing at least one amorphous substrate and at least one hydrogenating-dehydrogenating element selected from at least one group VIB base element and at least one group VIII base element, at a temperature from 200°C to 390°C, pressure from 2 to 16 MPa, volumetric velocity from 0.2 to 5 h-1, and with such an amount of injected hydrogen that the volume ratio of a number of liters of hydrogen to a number of liters of hydrocarbon is from 100 to 2000 l/l.
EFFECT: obtaining a combined method for hydrocracking and hydrotreatment.
15 cl, 8 tbl, 2 ex, 1 dwg
Authors
Dates
2023-08-21—Published
2018-06-15—Filed