CN111978986B

CN111978986B - Method for producing gasoline by hydrogenation conversion of aromatic hydrocarbon-containing diesel oil fraction

Info

Publication number: CN111978986B
Application number: CN201910436687.6A
Authority: CN
Inventors: 孙士可; 彭冲; 庞宏; 曹正凯
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: Sinopec Dalian Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2019-05-23
Filing date: 2019-05-23
Publication date: 2021-10-08
Anticipated expiration: 2039-05-23
Also published as: CN111978986A

Abstract

The invention discloses a method for producing gasoline by hydrogenation conversion of diesel containing aromatic hydrocarbon. The method comprises the following steps: a) step one, the reaction pressure is lower than the highest operation pressure, the reaction temperature of the conversion reactor is increased, the single bed temperature rise or the total bed temperature rise of the conversion reactor is kept to reach the maximum operation temperature rise until the quality of the gasoline component reaches the standard; b) a step of gradually increasing the reaction pressure while increasing the reaction temperature of the shift reactor to maintain the shift rate of the shift reactor at a value not lower than a design value; c) a step of keeping the reaction temperature of the conversion reactor constant and only increasing the reaction pressure until the reaction pressure reaches the design pressure or the conversion is lower than the design value. The method can accelerate the deactivation rate of the catalyst at the initial startup stage, shorten the startup stability adjustment time, and simultaneously prolong the device operation period.

Description

Method for producing gasoline by hydrogenation conversion of aromatic hydrocarbon-containing diesel oil fraction

Technical Field

The invention relates to a hydrogenation conversion method of diesel containing aromatic hydrocarbon, in particular to a method for producing a high-octane gasoline component by hydrogenation conversion of diesel containing aromatic hydrocarbon.

Technical Field

The catalytic diesel oil has high aromatic hydrocarbon content, so that the catalytic diesel oil has high density and low cetane number, is the diesel oil blending component with the worst property, and is also the diesel oil component with the largest processing difficulty in quality upgrading. The content of aromatic hydrocarbon is as high as more than 60%, wherein polycyclic aromatic hydrocarbon accounts for more than 50% of total aromatic hydrocarbon. For the diesel fraction, the naphtha fraction with high aromatic content can be used as a high-octane gasoline blending component, and the naphtha fraction with high aromatic content can be used for producing high-value-added naphtha products by effectively utilizing the aromatic hydrocarbon rich in the catalytic diesel.

At present, the hydrocracking technology is adopted to convert the catalytic cracking light cycle oil into the ultra-low sulfur diesel oil and the high octane gasoline blending component. Such as: NPRA annual meeting, Da vi a. pappal et al, 1995, introduced MAK-LCO technology developed by Mobil, Akzo Nobel and m.w. kellogg; NPRA annual meeting in 2005, Vasant P. Thakkar et al introduced LCO unicacking developed by UOP corporation^TMTechnology and HC-190 specialized catalyst. It is reported that the above two kindsThe technology can convert low-value catalytic cycle oil components into high-octane gasoline components and high-quality diesel oil blending components. In addition, UOP introduced its new LCO-X technology developed at NPRA annual meeting in 2007, which enabled a new approach to aromatics production with catalytic light cycle oils via hydroconversion-selective transalkylation route.

In China, a single-stage series process flow is adopted in the FD2G catalytic diesel oil hydro-conversion technology developed by the research institute of petrochemical industry, which is comforted by the company Limited in petrochemical industry, and part of high-octane gasoline blending components are produced by catalytic diesel oil through hydro-conversion. This technique has been used industrially. Therefore, the utilization of low-value catalytic light cycle oil at home and abroad is in continuous exploration and progress, and the direct modification of the oil is improved to the level of oiling combination from the beginning.

US5114562 discloses a two-stage diesel hydrotreating process, one of which employs a conventional hydrofining catalyst to remove impurities such as sulfur, nitrogen and the like from the raw materials, and the second stage employs a catalyst with higher hydrogenation saturation activity to carry out deep dearomatization.

US4971680 discloses a process for the selective cracking of aromatics, especially bicyclic aromatics, in diesel fuel to gasoline components using a hydrocracking catalyst. However, the octane number of the gasoline product is low and further treatment is still needed.

At present, the technology for producing gasoline by hydrocracking aromatic-containing diesel oil generally has the problem that the octane number of a gasoline product is low due to excessive hydrogenation saturation of aromatic hydrocarbon caused by overhigh hydrogenation activity of a catalyst at the initial startup stage. And the problem of short operation period caused by too high deactivation rate of the catalyst in the operation process. Under the existing situation, the method can greatly shorten the stable adjustment time at the initial startup stage and prolong the operation period by deeply researching the reaction mechanism and optimizing the process conditions, and has very important significance for oil refining enterprises.

Disclosure of Invention

The invention aims to solve the technical problems of shortening the start-up stable time of the diesel oil hydroconversion process and prolonging the running period of the device.

The technical scheme of the invention is as follows:

a method for producing gasoline by hydrogenation conversion of diesel fraction containing aromatic hydrocarbon comprises passing diesel fraction containing aromatic hydrocarbon and hydrogen through a hydrogenation refining reactor filled with hydrogenation refining catalyst under hydrogenation refining condition, passing the obtained hydrogenation refining effluent through the hydrogenation conversion reactor under hydrogenation conversion condition to contact and react with the hydrogenation conversion catalyst, carrying out gas-liquid separation on the hydrogenation conversion effluent, and fractionating liquid to obtain gas, gasoline component and diesel component; the method sequentially comprises the following steps:

a) step one, the reaction pressure is lower than the highest operation pressure, the reaction temperature of the conversion reactor is increased, the single bed temperature rise or the total bed temperature rise of the conversion reactor is kept to reach the maximum operation temperature rise until the quality of the gasoline component reaches the standard;

b) a step of gradually increasing the reaction pressure, increasing the reaction temperature of the conversion reactor, and keeping the conversion rate of the conversion reactor not lower than a design value;

c) a step of keeping the reaction temperature of the conversion reactor constant and only increasing the reaction pressure until the reaction pressure reaches the design pressure or the conversion is lower than the design value.

The design value of the conversion rate in the invention generally means that the conversion rate is 35-45 wt% when the temperature of a conversion reactor is higher than 205 ℃.

In the invention, the condition that the quality of the gasoline component reaches the standard means that the research octane number is not less than 90.

In step b), the average rate of increase in the reaction pressure is represented by the following formula:

(ii) a Wherein-10^-4A is not less than 0, B is not less than 0 and not more than 0.01, A, B cannot be zero at the same time. Δ P is the rate of increase in hydrogen partial pressure (MPa/d), t is the operating time (day), and ρ is the feedstock oil density (g/cm)³) T is the average temperature (DEG C) of the conversion reactor, A is a constant E < -10 ∈^-4，0]B is a constant E [0, 0.01 ]]。

The aromatic hydrocarbon content of the aromatic hydrocarbon-containing diesel fraction is more than 50 wt%, preferably more than 70 wt%; the initial boiling point is generally 50-280 ℃, and the 95wt% distillation temperature is generally 330-450 ℃. The content of polycyclic aromatic hydrocarbon (which means aromatic hydrocarbon with more than two rings) in the aromatic hydrocarbon-containing diesel oil is more than 30 wt percent, and preferably more than 40wt percent.

The aromatic hydrocarbon-containing diesel oil fraction is usually selected from one or more of catalytic cracking diesel oil, raffinate oil of an aromatic hydrocarbon extraction device, coal liquefaction diesel oil, coal tar diesel oil and shale oil diesel oil fraction.

In the invention, the hydrofining conditions are as follows: the reaction pressure is 2.0-16.0 MPa, the volume ratio of hydrogen to oil is 300: 1-1500: 1, and the volume airspeed is 0.1-5.0 h^-1The reaction temperature is 200-450 ℃; the preferred conditions are: the preferable operation conditions are that the reaction pressure is 4.0-12.0 MPa, the volume ratio of hydrogen to oil is 300: 1-1500: 1, and the volume airspeed is 2.0-3.0 h^-1The reaction temperature is 250-430 ℃.

The hydroconversion conditions are as follows: the reaction pressure is 2.0-16.0 MPa, the volume ratio of hydrogen to oil is 300: 1-1500: 1, and the volume airspeed is 0.5-5.0 h^-1The reaction temperature is 200-450 ℃; preferred operating conditions are: the reaction pressure is 3.0-10.0 MPa, the volume ratio of hydrogen to oil is 300: 1-1500: 1, and the volume airspeed is 1.0-2.0 h^-1The reaction temperature range is 300-420 ℃.

The specific operation process of the step b) is as follows: on the premise of keeping the conversion rate of the conversion reactor not lower than the designed value, the operation pressure of the system is firstly increased, then the reaction temperature is increased, and the pressure raising operation and the temperature raising operation are usually carried out alternately.

The hydrorefining reactor is filled with a hydrorefining catalyst. The hydrofining catalyst can adopt a conventional diesel hydrofining catalyst, generally uses VIB group and/or VIII group metals as active components, uses alumina or silicon-containing alumina as a carrier, and uses Mo and/or W as the VIB group metals and Co and/or Ni as the VIII group metals. Based on the weight of the catalyst, the content of the VIB group metal is 8-28 wt% calculated by oxide, and the content of the VIII group metal is 2-15 wt% calculated by oxide; the properties are as follows: the specific surface area is 100 to 650m²A pore volume of 0.15 to 0.8 mL/g, and a wide variety of commercial catalysts can be selected, for example, smoothingHydrofining catalysts such as 3936, 3996, FF-16, FF-26, FF-36, FF-46, FF56, FF-66, FH-98, FH-UDS and the like which are developed by the petrochemical research institute (FRIPP); conventional hydrotreating catalysts may also be prepared as desired according to common general knowledge in the art.

The hydroconversion reactor is filled with a hydroconversion catalyst. The hydro-conversion catalyst comprises a cracking component and a hydrogenation component. The cracking component generally comprises amorphous silica-alumina and/or a molecular sieve, such as a Y-type or USY molecular sieve, wherein the content of the Y-type molecular sieve is 10-70 wt%, preferably 30-60 wt% based on the weight of the catalyst; the binder is typically alumina or silica. The hydrogenation component is selected from metals, metal oxides or metal sulfides in groups VI, VII or VIII, and more preferably one or more of iron, chromium, molybdenum, tungsten, cobalt, nickel or sulfides or oxides thereof. The content of the hydrogenation component is 5-40 wt% based on the weight of the catalyst. The conventional hydroconversion catalyst can be selected from various existing commercial catalysts, such as 3824, FC-24B, FC-46, FC-52, FC-70A, FC-70B and the like developed by FRIPP. Specific hydroconversion catalysts may also be prepared as required according to common general knowledge in the art.

The Y-type molecular sieve used in the hydroconversion catalyst preferably has the following properties: if the unit cell constant is 2.425 to 2.450nm, SiO₂/Al₂O₃The molar ratio is 5.0-50.0, and the relative crystallinity is 80-130%.

In the method, the initial start-up is carried out according to the step a), and when the conversion rate of the conversion reactor can not reach the design value by means of adjusting the reaction temperature, or the nitrogen content of the refined effluent can not meet the requirements of the hydro-conversion catalyst by adjusting the reaction temperature, or the quality of the gasoline component reaches the standard, the step b) is switched. When the highest temperature in the reactor reaches the upper limit of the using temperature of the reactor, switching to the step c).

In the method, the aromatic hydrogenation saturation reaction is an exothermic reaction, and the reaction equilibrium constant is reduced along with the increase of the reaction temperature. As the reaction proceeds, the reaction process gradually changes from kinetic control to thermodynamic control. Therefore, with the increase of the reaction temperature, the content of aromatic hydrocarbon in the product also shows a tendency of decreasing first and then increasing. When the conversion rate reaches the standard, the reaction temperature exceeds the kinetic control range, and the reaction is controlled by thermodynamics. Therefore, the reaction temperature of the conversion section is continuously increased, the aromatic hydrocarbon saturation depth is reduced, the aromatic hydrocarbon is favorably kept in the gasoline product, and the octane number of the gasoline product is improved.

During conventional hydrocracking reactions, the reaction pressure has essentially no effect on the product distribution. In the research of the applicant, the change of the reaction pressure in the hydrogenation conversion reaction process of the diesel oil containing the aromatic hydrocarbon of the invention directly influences the conversion rate of the hydrogenation conversion reaction, different from the conventional hydrocracking. The diesel oil containing aromatic hydrocarbon is rich in a large amount of aromatic hydrocarbon compounds with double-ring and three-ring structures, and the aromatic hydrocarbon has stable property and is difficult to directly open the ring and crack. The macromolecular polycyclic aromatic hydrocarbon can be subjected to ring opening and further cracking reaction only after aromatic ring hydrogenation saturation to a certain degree. The reaction pressure is an important influence factor of the aromatic hydrocarbon hydrogenation saturation reaction, and the aromatic hydrocarbon hydrogenation saturation can be promoted by increasing the reaction pressure, so that the reaction temperature of ring opening and cracking is reduced, and the conversion rate of hydrogenation conversion is indirectly increased.

Compared with the prior art, the method has the following beneficial effects:

1. the method can solve the problems of excessive catalyst hydrogenation activity and low octane number of gasoline products caused by excessive saturation of aromatic hydrocarbon in the initial start-up period of the conventional hydrogenation conversion process of the diesel containing aromatic hydrocarbon. By reasonably controlling the reaction pressure and adjusting the reaction temperature, the deactivation rate of the catalyst at the initial start-up stage can be accelerated, and the over-saturation of the aromatic hydrocarbon component can be reduced. By matching the reaction pressure and the reaction temperature, the optimal reaction area of aromatic hydrocarbon hydrogenation saturation is avoided, so that the inferior aromatic hydrocarbon-containing diesel oil (such as catalytic diesel oil) can be partially converted into a high-octane gasoline component.

2. Compared with the conventional hydro-conversion process, the method can realize that the octane number of the gasoline component can reach a higher level in a shorter time. In the prior art, the hydroconversion process can obtain the gasoline component with the octane number meeting the requirement only in about one month according to the conventional operation mode, and the startup stability adjustment time of the method can be shortened to 15-25 days, so that the gasoline product or the gasoline blending component meeting the requirement can be obtained. Moreover, in the method, in the last stage of the use of the device, the conversion rate can reach the standard without increasing the reaction temperature within a period of time by adjusting the reaction pressure under the condition that the activity of the catalyst is weakened, so that the operation period of the device is prolonged.

Drawings

FIG. 1 is a schematic process flow diagram of the process of the present invention.

Wherein, 1-the first reaction zone, 2-the second reaction zone, 3-the gas-liquid separation zone, 4-the fractionation zone, 5-the recycle hydrogen compressor, 7, 8, 9, 10, 11, 13, 14, 15, 16-the pipeline.

Detailed Description

The method of the present invention is described in further detail below with reference to the accompanying drawings.

Some necessary equipment such as heating furnaces, pumps, heat exchangers, etc. are omitted from fig. 1. The omitted equipment is well known to those skilled in the art and is therefore not described in detail in fig. 1.

As shown in figure 1, the hydrogenation conversion method of diesel oil containing aromatic hydrocarbon comprises a first reaction zone 1 and a second reaction zone 2, wherein the first reaction zone 1 is filled with a hydrocracking pretreatment catalyst, and the second reaction zone 2 is filled with a hydrogenation conversion catalyst.

Raw oil passes through a pipeline 6, is mixed with hydrogen passing through a pipeline 7, and then enters a first reaction zone 1 through a pipeline 12 to carry out hydrofining reaction; the reaction effluent enters a second reaction zone through a pipeline 13 and undergoes a hydroconversion reaction in the presence of hydrogen and a hydroconversion catalyst; the reaction effluent is passed via line 14 to gas-liquid separation zone 3 where it is separated into hydrogen-rich gas and liquid product. The gas-liquid separation zone 3 typically comprises a high-pressure separator and a low-pressure separator. The hydrogen-rich gas enters the recycle hydrogen compressor 5 through a pipeline 16, and the compressed hydrogen-rich gas is mixed with make-up hydrogen introduced through a pipeline 8 and then forms recycle hydrogen through a pipeline 7. The liquid product obtained from the gas-liquid separation zone 3 enters the fractionation zone 4 through a pipeline 15, and gas, gasoline components and diesel oil products are obtained through

pipelines

9, 10 and 11 respectively.

The scheme and effects of the present invention are illustrated by specific examples below.

The technical solution and effects of the present invention will be described below by way of specific examples. The properties of the raw oils used are shown in Table 1. The catalysts used are listed in table 2, catalyst a being a hydroconversion pretreatment catalyst and catalyst B being a hydroconversion catalyst.

TABLE 1 Properties of the stock oils

TABLE 2 catalyst Properties

Example 1

The flow shown in fig. 1 is used. Two reactors are provided, R1 is a hydrogenation pretreatment reactor, and R2 is a hydroconversion reactor. Catalyst A was packed in R1, and catalyst B was packed in R2. The space velocity of the volume of the refining reactor is 1.5h^-1The volume space velocity of the conversion reactor is 1.5h^-1The highest operation pressure of the device is 10.0MPa, the highest operation temperature is 405 ℃, the total temperature rise of the highest operation is 100 ℃, and the design conversion rate>40wt% and the octane number not less than 90 in gasoline product research.

The method comprises the following steps:

(1) at the initial stage of start-up, the reaction pressure is 6.3MPa, and the initial reaction temperature is 381 ℃; gradually increasing the reaction temperature of the conversion reactor to enable the total bed temperature rise to reach the upper operation limit of 100 ℃, and operating for 520 hours until the octane number of the gasoline product reaches the standard; switch over to

Step (2): gradually increasing the reaction pressure at the rate of 0-0.005 MPa/day, increasing the reaction temperature to keep the conversion rate more than 40wt%, and keeping the reaction temperature to reach the upper limit of the use temperature of the conversion reactor of 405 ℃ until 16000 hours; switch over to

And (3): the reaction temperature of the conversion reactor is kept unchanged at 405 ℃, the reaction pressure is only increased, and after running for 25000 hours, the device reaches the design pressure of 10MPa, and the conversion rate is 40 wt%. And (5) turning to a shutdown stage. The process conditions and product properties for each step are shown in Table 3.

Comparative example 1

The flow shown in fig. 1 is used. Two reactors are provided, R1 is a hydrogenation pretreatment reactor, and R2 is a hydroconversion reactor. Catalyst A was packed in R1, and catalyst B was packed in R2. The space velocity of the volume of the refining reactor is 1.5h^-1The volume space velocity of the conversion reactor is 1.5h^-1The highest operation pressure of the device is 10.0MPa, the highest operation temperature is 405 ℃, the highest operation temperature rise is 100 ℃, and the conversion rate is designed>40wt% and the octane number not less than 90 in gasoline product research.

The method comprises the following steps: the reaction pressure is 6.3MPa, and the reaction temperature of the conversion reactor is gradually increased to ensure that the total bed temperature rise reaches the upper operation limit of 100 ℃. The octane number of the gasoline product reaches the standard after the operation for 520 hours. After the operation lasts for 1200 hours, the reaction temperature of the conversion section reaches 405 ℃, the conversion rate is reduced to 40wt%, and the operation is switched to a shutdown stage. The process conditions and product properties for each stage are shown in Table 4.

Comparative example 2

The method comprises the following steps: the reaction pressure is 10.0MPa, and the reaction temperature of the conversion reactor is gradually increased to ensure that the total bed temperature rise reaches the operation upper limit of 100 ℃. The octane number of the gasoline product reaches the standard after the operation is carried out for 2500 hours. After the operation is carried out for 25000 hours, the reaction temperature of the conversion section reaches 405 ℃, the conversion rate is reduced to 40wt%, and the shutdown stage is carried out. The process conditions and product properties for each stage are shown in Table 5.

TABLE 3 Process conditions and product Properties

*: switching to step b after 520 hours

**: switch to step c) after 16000 hours.

TABLE 4 Process conditions and product Properties

TABLE 5 Process conditions and product Properties

It can be seen from the data results of the examples and comparative examples that the hydroconversion process of the present invention can achieve a high octane number of gasoline products in a short period of time, and prolong the service life of the catalyst to achieve the purpose of long-term operation.

Claims

1. A method for producing gasoline by hydrogenation conversion of diesel fraction containing aromatic hydrocarbon comprises passing diesel fraction containing aromatic hydrocarbon and hydrogen through a hydrogenation refining reactor filled with hydrogenation refining catalyst under hydrogenation refining condition, passing the obtained hydrogenation refining effluent through the hydrogenation conversion reactor under hydrogenation conversion condition to contact and react with the hydrogenation conversion catalyst, carrying out gas-liquid separation on the hydrogenation conversion effluent, and fractionating liquid to obtain gas, gasoline component and diesel component; the method sequentially comprises the following steps:

b) a step of gradually increasing the reaction pressure while increasing the reaction temperature of the shift reactor to maintain the shift rate of the shift reactor at a value not lower than a design value;

c) a step of keeping the reaction temperature of the conversion reactor unchanged and only increasing the reaction pressure until the reaction pressure reaches the design pressure or the conversion rate is lower than the design value;

wherein, the initial start-up is carried out according to the step a), and when the conversion rate of the conversion reactor can not reach the design value by means of adjusting the reaction temperature, or the nitrogen content of the refined effluent can not meet the requirement of the hydrogenation conversion catalyst by adjusting the reaction temperature, or the quality of the gasoline component can not reach the standard by adjusting the reaction temperature, the step b) is switched; when the highest temperature in the reactor reaches the upper limit of the using temperature of the reactor, switching to the step c).

2. The process of claim 1, wherein the design value is a conversion rate of 35 to 45 wt% at > 205 ℃ in the conversion reactor.

3. The process of claim 1 wherein said gasoline component quality attainment is no less than 90 octane number research.

4. The process of claim 1, wherein in step b), the average rate of increase in reaction pressure is represented by the following equation:

；

wherein, the delta P is the hydrogen partial pressure increasing rate, and the unit is MPa/d; t is the running time in units of d; rho is the density of the raw oil in g/cm³(ii) a T is the average temperature of the conversion reactor and the unit is; -10^-4A is more than or equal to 0, B is more than or equal to 0 and less than or equal to 0.01, A, B are constants and cannot be simultaneously zero.

5. The process according to claim 1, wherein the aromatic content of the aromatic-containing diesel fraction is 50 wt% or more, the initial boiling point is 50 ℃ to 280 ℃, the 95wt% distillation temperature is 330 ℃ to 450 ℃, and the aromatic content of the two or more rings is 30 wt% or more.

6. The method according to claim 5, wherein the aromatic hydrocarbon-containing diesel fraction is one or more selected from the group consisting of catalytic cracking diesel, raffinate oil from an aromatic hydrocarbon extraction unit, coal liquefaction diesel, coal tar diesel, and shale oil diesel fraction.

7. The process of claim 1, wherein the hydrofinishing conditions are: the reaction pressure is 2.0-16.0 MPa, the volume ratio of hydrogen to oil is 300: 1-1500: 1, and the volume airspeed is 0.1-5.0 h^-1The reaction temperature is 200-450 ℃; the hydroconversion conditions are as follows: the reaction pressure is 2.0-16.0 MPa, the volume ratio of hydrogen to oil is 300: 1-1500: 1, and the volume airspeed is 0.5-5.0 h^-1The reaction temperature is 200-450 ℃.

8. The method of claim 1, wherein step b) is performed as follows: on the premise of keeping the conversion rate of the conversion reactor not lower than the designed value, the operation pressure of the system is firstly increased, then the reaction temperature is gradually increased, and then the pressure raising operation and the temperature raising operation are alternately carried out.

9. The process of claim 1 wherein said hydrofinishing catalyst is a diesel hydrofinishing catalyst; the diesel oil hydrorefining catalyst has VIB group and/or VIII group metal as active component and alumina or silicon-containing alumina as carrier; based on the weight of the catalyst, the content of the VIB group metal is 8-28 wt% calculated by oxide, and the content of the VIII group metal is 2-15 wt% calculated by oxide; the properties are as follows: the specific surface area is 100 to 650m²The pore volume is 0.15-0.8 mL/g.

10. The process of claim 1 wherein said hydroconversion catalyst comprises a cracking component and a hydrogenation component, the cracking component comprising amorphous silica and/or Y-type molecular sieve; taking the weight of the catalyst as a reference, the content of the Y-type molecular sieve is 10-70 wt%; the adhesive is aluminum oxide or silicon oxide; the hydrogenation component is one or more of metals, metal oxides or metal sulfides from a VIB group, a VII group or a VIII group.

11. The process of claim 10 wherein the hydrogenation component is selected from at least one of iron, chromium, molybdenum, tungsten, cobalt, nickel, sulfides thereof, or oxides thereof; the content of the hydrogenation component is 5-40 wt% based on the weight of the catalyst.

12. The process of claim 10 or 11, wherein the Y-type molecular sieve has the following properties: a unit cell constant of 2.425 to 2.450nm, SiO₂/Al₂O₃The molar ratio is 5.0-50.0, and the relative crystallinity is 80-130%.

13. A process according to claim 5, wherein the aromatic content of the aromatic-containing diesel fraction is 70 wt.% or more and the aromatic content of the bicyclic aromatic hydrocarbon or more is 40 wt.% or more.

14. The process of claim 10, wherein the Y-type molecular sieve content is from 30 to 60 wt% based on the weight of the hydroconversion catalyst.