Method for producing hydrocarbon fractions

Abstract

A method for producing an LPG fraction, a gasoline fraction, a kerosene fraction, a gas oil fraction, monocyclic aromatic hydrocarbon and a non-aromatic naphtha fraction from hydrocracked oil includes hydrocracking hydrocarbon oil containing polycyclic aromatic hydrocarbon to convert into a light hydrocarbon fraction, and efficiently and selectively producing monocyclic aromatic hydrocarbon with higher valuable alkylbenzenes. The method for producing hydrocarbon fraction comprises subjecting hydrocarbon feedstock containing polycyclic aromatic hydrocarbon and in which the ratio of carbons constituting an aromatic ring to the total carbons in the hydrocarbon oil (the aromatic ring-constituting carbon ratio) is 35 mole % or more to catalytic cracking in the presence of hydrogen. 40% or more of a fraction with a boiling point of 215° C. or higher in the hydrocarbon feedstock is converted into a fraction with a boiling point lower than 215° C., producing hydrocracked oil containing 30 vol % or more of monocyclic aromatic hydrocarbon.

1 . A method for producing hydrocarbon fractions comprising a step of catalytically hydrocracking a hydrocarbon feedstock containing polycyclic aromatic hydrocarbons and having not less than 35 mol % of an aromatic ring-constituting carbon ratio, which is the ratio of carbon atoms constituting aromatic rings to the total number of carbon atoms of the hydrocarbon oil, in the presence of hydrogen to convert not less than 40% of the fractions having a boiling point of not less than 215° C. to fractions having a boiling point of less than 215° C. and produce a hydrocracked oil containing 30 vol % or more of monocyclic aromatic hydrocarbons. 
   
   
       2 . The method according to  claim 1 , wherein the operating conditions in the hydrocracking step are 2 to 10 MPa of a pressure, 200 to 450° C. of a temperature, 0.1 to 10.0 h −1  of a LHSV, 100 to 5000 NL/L of a hydrogen/oil ratio, and not less than 0.5 of an aromatic ring carbon remaining ratio, which is the ratio of the aromatic ring-constituting carbon ratio of the hydrocracked oil to the aromatic ring-constituting carbon ratio of the hydrocarbon feedstock. 
   
   
       3 . The method according to  claim 1 , wherein the hydrocarbon feedstock is a hydrocarbon oil fraction obtained from a catalytic cracker, a thermal cracker, an ethylene cracker, a supercritical fluid cracker, or a catalytic reformer or a mixture of two or more of these hydrocarbon oil fractions. 
   
   
       4 . The method according to  claim 1 , wherein the hydrocarbon feedstock has distillation properties of a 10 vol % distillate temperature of 140 to 230° C. and a 90 vol % distillate temperature of 230 to 600° C. 
   
   
       5 . The method according to  claim 1 , further comprising a separation step of obtaining at least two hydrocarbon fractions selected from an LPG fraction, a gasoline fraction, a kerosene fraction, a gas oil fraction, a non-aromatic naphtha fraction, and a monocyclic aromatic hydrocarbons from a hydrocracked oil obtained by hydrocracking. 
   
   
       6 . The method according to  claim 1 , wherein the hydrocracking catalyst comprises a carrier which comprises a composite oxide and a binder combining the composite oxide and at least one metal selected from the Group VI metals and Group VIII metals of the periodic table supported on the carrier, and has properties of a specific surface area of 100 to 800 m 2 /g, a median pore diameter of 3 to 15 nm, and a pore volume occupied by pores with a pore diameter of 2 to 60 nm of 0.1 to 1.0 mL/g. 
   
   
       7 . The method according to  claim 6 , wherein the composite oxide contains at least one of silica-alumina, silica-titania, silica-zirconia, silica-magnesia, silica-alumina-titania, silica-alumina-zirconia, tungstated zirconia, sulfated zirconia, and zeolite. 
   
   
       8 . The method according to  claim 6 , wherein the binder comprises at least one of alumina, silica-alumina, and boria-alumina. 
   
   
       9 . The method according to  claim 2 , wherein the hydrocarbon feedstock is a hydrocarbon oil fraction obtained from a catalytic cracker, a thermal cracker, an ethylene cracker, a supercritical fluid cracker, or a catalytic reformer or a mixture of two or more of these hydrocarbon oil fractions. 
   
   
       10 . The method according to  claim 2 , wherein the hydrocarbon feedstock has distillation properties of a 10 vol % distillate temperature of 140 to 230° C. and a 90 vol % distillate temperature of 230 to 600° C. 
   
   
       11 . The method according to  claim 3 , wherein the hydrocarbon feedstock has distillation properties of a 10 vol % distillate temperature of 140 to 230° C. and a 90 vol % distillate temperature of 230 to 600° C. 
   
   
       12 . The method according to  claim 2 , further comprising a separation step of obtaining at least two hydrocarbon fractions selected from an LPG fraction, a gasoline fraction, a kerosene fraction, a gas oil fraction, a non-aromatic naphtha fraction, and a monocyclic aromatic hydrocarbons from a hydrocracked oil obtained by hydrocracking. 
   
   
       13 . The method according to  claim 3 , further comprising a separation step of obtaining at least two hydrocarbon fractions selected from an LPG fraction, a gasoline fraction, a kerosene fraction, a gas oil fraction, a non-aromatic naphtha fraction, and a monocyclic aromatic hydrocarbons from a hydrocracked oil obtained by hydrocracking. 
   
   
       14 . The method according to  claim 4 , further comprising a separation step of obtaining at least two hydrocarbon fractions selected from an LPG fraction, a gasoline fraction, a kerosene fraction, a gas oil fraction, a non-aromatic naphtha fraction, and a monocyclic aromatic hydrocarbons from a hydrocracked oil obtained by hydrocracking. 
   
   
       15 . The method according to  claim 2 , wherein the hydrocracking catalyst comprises a carrier which comprises a composite oxide and a binder combining the composite oxide and at least one metal selected from the Group VI metals and Group VIII metals of the periodic table supported on the carrier, and has properties of a specific surface area of 100 to 800 m 2 /g, a median pore diameter of 3 to 15 nm, and a pore volume occupied by pores with a pore diameter of 2 to 60 nm of 0.1 to 1.0 mL/g. 
   
   
       16 . The method according to  claim 3 , wherein the hydrocracking catalyst comprises a carrier which comprises a composite oxide and a binder combining the composite oxide and at least one metal selected from the Group VI metals and Group VIII metals of the periodic table supported on the carrier, and has properties of a specific surface area of 100 to 800 m 2 /g, a median pore diameter of 3 to 15 nm, and a pore volume occupied by pores with a pore diameter of 2 to 60 nm of 0.1 to 1.0 mL/g. 
   
   
       17 . The method according to  claim 4 , wherein the hydrocracking catalyst comprises a carrier which comprises a composite oxide and a binder combining the composite oxide and at least one metal selected from the Group VI metals and Group VIII metals of the periodic table supported on the carrier, and has properties of a specific surface area of 100 to 800 m 2 /g, a median pore diameter of 3 to 15 nm, and a pore volume occupied by pores with a pore diameter of 2 to 60 nm of 0.1 to 1.0 mL/g. 
   
   
       18 . The method according to  claim 5 , wherein the hydrocracking catalyst comprises a carrier which comprises a composite oxide and a binder combining the composite oxide and at least one metal selected from the Group VI metals and Group VIII metals of the periodic table supported on the carrier, and has properties of a specific surface area of 100 to 800 m 2 /g, a median pore diameter of 3 to 15 nm, and a pore volume occupied by pores with a pore diameter of 2 to 60 nm of 0.1 to 1.0 mL/g. 
   
   
       19 . The method according to  claim 9  wherein the hydrocarbon feedstock has distillation properties of a 10 vol % distillate temperature of 140 to 230° C. and a 90 vol % distillate temperature of 230 to 600° C. 
   
   
       20 . The method according to  claim 9  further comprising a separation step of obtaining at least two hydrocarbon fractions selected from an LPG fraction, a gasoline fraction, a kerosene fraction, a gas oil fraction, a non-aromatic naphtha fraction, and a monocyclic aromatic hydrocarbons from a hydrocracked oil obtained by hydrocracking.