A method for producing dimethylnaphthalene using a fluidized bed reactor

Abstract

This disclosure relates to a method for producing dimethylnaphthalene using a fluidized bed reactor. The method includes: S1, mixing a naphthalene-rich hydrocarbon oil with a methylating agent and introducing the mixture into a turbulent fluidized bed reactor to contact the catalyst and perform a methylation reaction in the presence of a fluidizing medium; the resulting oil is then separated to obtain a spent catalyst and methylated oil; S2, the methylated oil is further separated to obtain reaction gas, naphthalene-containing aromatic oil, and a circulating oil containing non-aromatic hydrocarbons and / or naphthalene and methylnaphthalene fractions; S3, the naphthalene-containing aromatic oil is desulfurized and denitrogenated, and then subjected to aromatic extraction in an extraction unit to obtain an aromatic mixture; the aromatic mixture is further separated to obtain BTX monocyclic aromatic hydrocarbons, dimethylnaphthalene, and raffinate oil; S4, the spent catalyst is introduced into a regenerator for regeneration to obtain a regenerated catalyst, which is then returned to the turbulent fluidized bed reactor. This method enables low-cost and stable continuous production.

Description

Technical Field

[0001] This application belongs to the field of petrochemicals, and specifically relates to a method for producing dimethylnaphthalene using a fluidized bed reactor. Background Technology

[0002] Dimethylnaphthalene is an important class of organic chemical raw materials with wide industrial applications. For example, 2,6-dimethylnaphthalene (2,6-DMN) is a high-value-added aromatic product and an ideal raw material for the production of 2,6-naphthalenedicarboxylic acid. It can also be used to produce polymers such as polyester fibers, polyamides, and polysulfide fibers. Other dimethylnaphthalenes, besides being converted to 2,6-DMN through isomerization reactions, can also be used as excellent solvents and materials for carbon paper. However, the production cost of 2,6-DMN using benzene compounds and butadiene as raw materials is relatively high. To reduce the production cost of 2,6-DMN, ExxonMobil and Kobe Steel Corporation of Japan jointly developed a method using petroleum fractions of naphthalene compounds as raw materials. This method involves a fixed-bed reactor on a zeolite catalyst with a specific structure to carry out the alkylation reaction of the naphthalene compounds, followed by further isomerization. High-purity 2,6-DMN is then separated from the ten isomers after alkylation using a high-pressure crystallization method. Exxon-Mobil is currently the only company in the world that has successfully developed a method to produce dimethylnaphthalene using catalytic cracking light cycle oil (LCO) as a feedstock.

[0003] Catalytic cracking light cycle oil is rich in naphthalene compounds, usually exceeding 40%, and has a low cetane number, making it difficult to use as a diesel blending component in diesel quality upgrades. However, it is a potential and inexpensive resource of 2,6-dimethylnaphthalene. In addition to separating dimethylnaphthalene from LCO, further methylating naphthalene and methylnaphthalene to produce dimethylnaphthalene, especially 2,6-dimethylnaphthalene, undoubtedly has good development prospects.

[0004] For the methylation reaction of naphthalene compounds in catalytic cracking light cycle oil, existing research at home and abroad has mainly focused on the development of related catalysts. For example, Chinese literature CN101056834B discloses an MTW-structured zeolite catalyst for the methylation of naphthalene hydrocarbons, which is used in a fixed-bed reactor for batch or semi-continuous operation; Chinese literature CN102746101A discloses a CoAPO-11 molecular sieve catalyst for the preparation of 2,6-dimethylnaphthalene from naphthalene, alkylating agent, and trimethylbenzene, which is used in a fixed-bed reactor; and Chinese literature CN110694680A discloses the EU-1 / ZSM-23 mixed crystal molecular sieve, which is a catalyst for the preparation of 2,6-dimethylnaphthalene from syngas and 2-methylnaphthalene, using hydrogen-form nanoneedle-like crystals.

[0005] As described in the aforementioned literature, the methylation reaction of naphthalene compounds in catalytic cracking light cycle oil mainly employs solid acid catalysts such as molecular sieves or solid superacids. However, the methylation reaction of hydrocarbons on solid acid catalysts inevitably leads to coking. Coking reduces the activity of the methylation reaction, resulting in low dimethylnaphthalene yield and poor unit stability. Typically, the methylation reaction of naphthalene and methylnaphthalene shows a naphthalene conversion rate dropping to 19.87% after 20 hours due to catalyst coking, while the selectivity for 2,6-dimethylnaphthalene is only 6.66%. Therefore, to address the problem of poor reaction stability, Chinese literature CN109574783A discloses a method for producing polymethylnaphthalene by adding C5-C8 saturated hydrocarbons as a dehydrating agent to the reaction system of methylnaphthalene and methanol. This method can solve the problem of water generated by alcohol methylating agents affecting the activity of solid acid catalysts, but it cannot solve the coking problem.

[0006] Secondly, existing research both domestically and internationally focuses on the separation of naphthalene compounds from catalytic cracking light cycle oil. For example, Chinese literature CN100509719C discloses a method for complexing and separating 2,6-dimethylnaphthalene by adding a mixture of m-nitrobenzoic acid and methanol to a dimethylnaphthalene mixture; Chinese literature CN110759804A discloses an apparatus for extracting, distilling, and concentrating dimethylnaphthalene using a distillation column and a recovery column connected to the distillation column via a lower side stream. However, the dimethylnaphthalene content in catalytic cracking light cycle oil is typically 20%–30%, with an additional 10%–20% of naphthalene and methylnaphthalene, which need to be converted to dimethylnaphthalene to improve the utilization value of LCO and the economic efficiency of separation and utilization.

[0007] Therefore, in order to meet the growing demand for the chemical raw material dimethylnaphthalene and to achieve low-cost and stable continuous production, it is necessary to develop a method for producing dimethylnaphthalene by methylation of naphthalene, methylnaphthalene and other naphthalene derivatives using a fluidized bed reactor. Summary of the Invention

[0008] The purpose of this disclosure is to provide a method for producing dimethylnaphthalene by methylation using a fluidized bed reactor.

[0009] To achieve the above objectives, this disclosure provides a method for producing dimethylnaphthalene using a fluidized bed reactor, the method comprising:

[0010] S1. The hydrocarbon oil rich in naphthalene compounds is mixed with a methylating agent and introduced into a turbulent fluidized bed reactor to contact the catalyst and carry out a methylation reaction in the presence of a fluidized medium. The resulting oil is separated to obtain the catalyst to be generated and the methylated oil.

[0011] S2. Separate the methylated oil to obtain reaction gas, naphthalene-containing aromatic oil, and recycled oil containing non-aromatic hydrocarbons and / or naphthalene and methylnaphthalene fractions;

[0012] S3. After desulfurization and denitrogenation, the naphthalene-containing aromatic oil is extracted by an extraction unit to obtain an aromatic mixture; the aromatic mixture is then separated to obtain BTX monocyclic aromatic hydrocarbons, dimethylnaphthalene, and raffinate.

[0013] S4. The catalyst to be generated is introduced into the regenerator for regeneration to obtain a regenerated catalyst, and the regenerated catalyst is returned to the turbulent fluidized bed reactor.

[0014] Optionally, the naphthalene-rich hydrocarbon oil is selected from one or more of the following: catalytic cracking light cycle oil with a boiling point of 160–340 °C, coal tar, distillate oils rich in naphthalene and methylnaphthalene from other units, pure naphthalene hydrocarbon oil, and methylnaphthalene hydrocarbon oil; the other units are selected from one or more of the following: ethylene units, hydrocracking and coking units; and the naphthalene content in the naphthalene-rich hydrocarbon oil is 10–90% by weight.

[0015] Optionally, the molar ratio of the methylating agent to the naphthalene-rich hydrocarbon oil is 0.1 to 10, preferably 0.5 to 5.0; the methylating agent includes low alcohols and / or polymethylbenzenes; the low alcohols are selected from at least one of methanol, ethanol and isopropanol; the polymethylbenzenes are selected from at least one of tetramethylbenzene, pentamethylbenzene and hexamethylbenzene.

[0016] Optionally, the fluidizing medium is selected from hydrogen-containing gas and / or hydrogen-free gas; optionally, the hydrogen-containing gas is hydrogen or dry gas, and the hydrogen-free gas is nitrogen and / or water vapor.

[0017] Optionally, the conditions for the methylation reaction include: a reaction temperature of 300–600 °C; a reaction pressure of 0.2–2.0 MPa; a reaction time of 0.1–20 seconds; and a weight hourly space velocity of 0.1–20 h⁻¹. -1 The agent-to-oil weight ratio is 0.1-10; preferably, the reaction temperature is 400-550℃; the reaction pressure is 0.5-1.5 MPa; the reaction time is 1-10 seconds; and the weight hourly space velocity is 1.0-15 h⁻¹. -1 The weight ratio of the agent to oil is 1-8.

[0018] Optionally, the turbulent fluidized bed reactor is a fluidized bed and / or a riser reactor; the apparent average linear velocity of oil and gas in the turbulent fluidized bed reactor is 0.5-2.0 m / s.

[0019] Optionally, the extraction unit includes one or more aromatic extraction units; the plurality of aromatic extraction units may be the same or different; the aromatic extraction solvent used for the aromatic extraction is selected from at least one of plasma solvents, sulfolane, alcohol ethers, pyrrolidones and furfural.

[0020] Optionally, the method further includes: directly introducing the spent catalyst into the regenerator for regeneration, or introducing the spent catalyst into the regenerator for regeneration after dehydrogenation and depressurization in the catalyst hopper to obtain the regenerated catalyst; directly returning the obtained regenerated catalyst to the turbulent fluidized bed reactor, or returning the obtained regenerated catalyst to the turbulent fluidized bed reactor after deoxygenation and pressurization in the catalyst hopper.

[0021] Optionally, the regeneration conditions include: a temperature of 500–800°C and a pressure of 0.2–5.0 MPa; preferably, a temperature of 550–700°C and a pressure of 1.0–3.5 MPa.

[0022] Optionally, the method further includes: recycling the circulating oil obtained in step S2 and / or the raffinate obtained in step S3 back into the refining process.

[0023] Optionally, the catalyst has an average particle size of 40–150 micrometers;

[0024] Based on the weight of the catalyst, the catalyst comprises 20-80 wt% zeolite, 5-30 wt% inorganic oxides, 10-30 wt% clay, and 1-20 wt% active metal; preferably, the catalyst comprises 25-75 wt% zeolite, 10-25 wt% inorganic oxides, 15-25 wt% clay, and 5-15 wt% active metal; the zeolite comprises 50-100 wt% mesoporous zeolite and 0-50 wt% macroporous zeolite, preferably comprising 70-90 wt% mesoporous zeolite and 10-30 wt% macroporous zeolite; the mesoporous zeolite is selected from ZSM-5 zeolite, ZSM-11 zeolite, and ZS... The zeolite is selected from one or more of M-12 zeolite, ZSM-23 zeolite, ZSM-35 zeolite, ZSM-38 zeolite, ZSM-48 zeolite, and ZRP zeolite, wherein the macroporous zeolite is selected from one or more of REY zeolite, REHY zeolite, ultrastable Y zeolite, high-silica Y zeolite, and β zeolite; the inorganic oxide is silicon dioxide and / or aluminum oxide; the clay is selected from one or more of silicon dioxide, kaolin, hydrous kaolin, montmorillonite, diatomaceous earth, halloysite, soapstone, rettosite, sepiolite, attapulgite, hydrotalcite, and bentonite; and the active metal is selected from one or more of Group IA, Group IIA, VIA, VIIA, IB, IIB, or transition metal elements.

[0025] Compared with the prior art, the present disclosure has the following technical effects through the above technical solution:

[0026] (1) This disclosure uses a fluidized bed reactor. Compared with a fixed bed reactor, the fluidized bed reactor has higher requirements for catalyst strength, but higher reactor volume utilization, shorter reaction time, and larger throughput, making it more suitable for long-term continuous operation in large-scale production.

[0027] (2) This disclosure achieves the switching of different reaction atmospheres and / or reaction pressures through a catalyst hopper system, that is, the methylation reaction of naphthalene compounds is completed in a fluidized bed reactor under hydrogen- or non-hydrogen-containing pressure (0.2-2.0 MPa), while the catalyst activity is restored in a regenerated oxygen-containing atmosphere.

[0028] (3) The fluidized bed reactor in this disclosure is continuously regenerated, which solves the problem of catalyst coking affecting production stability and can realize self-heating of the reaction. The heat released by the regeneration and burning of coke supplies the heat required for the reaction, eliminating the need for external heating and greatly saving energy consumption.

[0029] (4) This disclosure uses catalytic cracking light cycle oil rich in naphthalene compounds as raw material for fluidized methylation to produce dimethylnaphthalene. Not only can it utilize the rich naphthalene compounds to produce dimethylnaphthalene, the process is short and the cost is low, but it can also utilize the monocyclic aromatic hydrocarbons in the light cycle oil to produce chemical materials such as BTX and low carbon olefins.

[0030] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0031] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0032] Figure 1 This is a schematic diagram of the process flow of the first embodiment of this disclosure.

[0033] Figure 2 This is a schematic diagram of the process flow for the second embodiment of this disclosure.

[0034] Explanation of reference numerals in the attached figures

[0035] Reactor inlet section I-1 Catalyst inlet I-2 First feedstock inlet

[0036] I-3 Circulating Oil Recycling Inlet, Reactor II Reaction Section, Reactor III Oil-Agent Separation Section

[0037] III-1 Reactor Transition Section; III-2 Stripping Section; III-3 Rapid Separator

[0038] IV Reactor Outlet Section IV-1 Filter IV-2 Reactor Oil and Gas Outlet

[0039] III-2-1 Catalyst outlet 1 Naphthalene-containing hydrocarbon oil 2 Methylating agent

[0040] 3 Fluidizing medium 4 Stripping medium 5 Reaction oil and gas pipeline

[0041] 6. Oil-gas separation system; 7. Gas products; 8. Light non-aromatic oil.

[0042] 9. Light aromatic oil; 10. Light cycle oil; 11. Heavy aromatic oil

[0043] 12 Heavy Cycle Oil; 13 Light Aromatics Extraction System; 14 Light Aromatics (mainly BTX)

[0044] 15 Aromatic raffinate oil 16 Heavy aromatic separation system 17 Dimethylnaphthalene

[0045] 18 Heavy Aromatics Residual Oil 19 Catalyst Hopper System 20 Ready-to-Produce Pipeline

[0046] 21 Regeneration pipeline 22 Regenerator 23 Oxygen-containing regeneration gas

[0047] 24 smoke Detailed Implementation

[0048] The following provides a detailed description of specific embodiments of this disclosure. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit this disclosure.

[0049] This disclosure provides a method for producing dimethylnaphthalene using a fluidized bed reactor, the method comprising:

[0050] S1. The hydrocarbon oil rich in naphthalene compounds is mixed with a methylating agent and introduced into a turbulent fluidized bed reactor to contact the catalyst and carry out a methylation reaction in the presence of a fluidized medium. The resulting oil is separated to obtain the catalyst to be generated and the methylated oil.

[0051] S2. Separate the methylated oil to obtain reaction gas, naphthalene-containing aromatic oil, and recycled oil containing non-aromatic hydrocarbons and / or naphthalene and methylnaphthalene fractions;

[0052] S3. After desulfurization and denitrogenation, the naphthalene-containing aromatic oil is extracted by an extraction unit to obtain an aromatic mixture; the aromatic mixture is then separated to obtain BTX monocyclic aromatic hydrocarbons, dimethylnaphthalene, and raffinate.

[0053] S4. The catalyst to be generated is introduced into the regenerator for regeneration to obtain a regenerated catalyst, and the regenerated catalyst is returned to the turbulent fluidized bed reactor.

[0054] The inventors of this disclosure have discovered through years of research that: (1) the content of naphthalene, alkylnaphthalene and other naphthalene compounds in catalytic cracking light cycle oil (LCO) is higher than 40%, of which the content of dimethylnaphthalene is usually 20% to 30%, but there are still 10% to 20% of naphthalene and methylnaphthalene, which can be methylated by solid acid catalysis to produce dimethylnaphthalene, thereby improving the resource utilization of LCO and supplementing the shortage of aromatic chemical raw materials such as dimethylnaphthalene; (2) the methylation reaction of naphthalene compounds usually uses solid acid catalysts, and the stronger the acidity and the higher the reaction severity, the more favorable the methylation reaction of naphthalene compounds is. However, the higher reaction severity and the stronger catalyst acid center can also easily lead to catalyst coking and deactivation; (3) the methylation reaction of naphthalene compounds is a slow reaction, and it is usually carried out in a fixed bed reactor under hydrogen-containing or non-hydrogen-containing atmosphere; while the regeneration of coking catalyst needs to be carried out in a high temperature and oxygen-rich atmosphere. Conventional fixed bed or fluidized bed devices are difficult to coordinate the reaction atmosphere of naphthalene compound methylation rich in hydrogen, methanol and light hydrocarbons and the different reaction atmosphere requirements of oxygen-containing regeneration. This disclosure employs a turbulent fluidized bed reaction system and a catalyst hopper system to isolate the reaction atmosphere, enabling continuous methylation reactions of naphthalene compounds and oxygen-containing regeneration and reactivation of coking catalysts, thereby achieving a high dimethylnaphthalene product yield from methylation of naphthalene compounds.

[0055] Based on the above findings, this disclosure provides a method for producing dimethylnaphthalene by methylation in a turbulent fluidized bed reactor. In the turbulent fluidized bed reactor, hydrocarbon oil containing naphthalene, methylnaphthalene, and other naphthalene compounds is contacted with a methylating agent and a methylation catalyst to carry out a methylation reaction. After desulfurization and nitrogen removal, the methylated oil is subjected to aromatic extraction to produce dimethylnaphthalene and aromatics such as benzene, toluene, and xylene. The coking and deactivated catalyst is regenerated and recycled after nitrogen stripping and dehydrogenation through a catalyst hopper system. This achieves a highly efficient and continuous production method for producing dimethylnaphthalene and other aromatics by methylation of naphthalene compounds, with high yields of high-value aromatics such as dimethylnaphthalene, and enables continuous production.

[0056] According to this disclosure, the naphthalene-rich hydrocarbon oil may be selected from one or more of the following: catalytic cracking light cycle oil with a boiling point of 160–340 °C, coal tar, distillate oils rich in naphthalene and methylnaphthalene from other units, pure naphthalene hydrocarbon oil, and methylnaphthalene hydrocarbon oil; the other units may be selected from one or more of the following: ethylene units, hydrocracking and coking units; the naphthalene content in the naphthalene-rich hydrocarbon oil may be 10–90% by weight.

[0057] In this disclosure, the hydrocarbon oil rich in naphthalene compounds can be preheated, and the preheating temperature can be 180-400℃, preferably 200-300℃.

[0058] According to this disclosure, the molar ratio of the methylating agent to the naphthalene-rich hydrocarbon oil can be 0.1 to 10, preferably 0.5 to 5.0; the methylating agent may include low alcohols and / or polymethylbenzenes; the low alcohols may be selected from at least one of methanol, ethanol and isopropanol; the polymethylbenzenes may be selected from at least one of tetramethylbenzene, pentamethylbenzene and hexamethylbenzene.

[0059] According to this disclosure, the fluidizing medium may be selected from hydrogen-containing gas and / or hydrogen-free gas; optionally, the hydrogen-containing gas is hydrogen or dry gas, and the hydrogen-free gas is nitrogen and / or water vapor.

[0060] According to this disclosure, the conditions for the methylation reaction may include: a reaction temperature of 300–600 °C; a reaction pressure of 0.2–2.0 MPa; a reaction time of 0.1–20 seconds; and a weight hourly space velocity of 0.1–20 h⁻¹. -1 The agent-to-oil weight ratio is 0.1-10; preferably, the reaction temperature is 400-550℃; the reaction pressure is 0.5-1.5 MPa; the reaction time is 1-10 seconds; and the weight hourly space velocity is 1.0-15 h⁻¹. -1 The weight ratio of the agent to oil is 1-8.

[0061] According to this disclosure, the turbulent fluidized bed reactor can be a fluidized bed and / or a riser reactor, preferably a fluidized bed reactor, and more preferably an upward turbulent fluidized bed reactor.

[0062] like Figure 1 and 2 As shown, the lower part of the reactor is the inlet section I, which is equipped with a catalyst inlet I-1 and a first feedstock oil inlet I-2. Above and / or below the first feedstock oil inlet, there is at least one circulating oil reprocessing inlet I-3. The middle part is the reaction section II, where the catalyst and reactant flow upward under gaseous fluidization, and the catalyst is in a turbulent fluidization state. The apparent average linear velocity of the oil and gas is 0.5-2.0 m / s. The upper part is the oil-catalyst separation section III, which is equipped with a transition section III-1, a stripping section III-2, and a rapid separator for catalyst and oil and gas III-3, which are arranged coaxially from bottom to top and have fluid flow between them. The top of the reactor is the outlet section IV, which is equipped with a filter IV-1 and a reaction oil and gas outlet IV-2.

[0063] Furthermore, a catalyst outlet III-2-1 is provided at the bottom of the stripping section. The oil and gas rise through the transition section and enter the oil-catalyst rapid separator III-3. The separated oil and gas are filtered by filter IV-1 and exit the reactor through the reaction oil and gas outlet IV-2, entering the separation system for product separation. The separated catalyst falls into the stripping section to settle and is stripped by nitrogen before exiting the reactor through the catalyst outlet III-2-1.

[0064] In this disclosure, methylated oil can be desorbed to remove impurities such as nitrides and sulfides, which can be done by adsorption and / or selective hydrogenation, with adsorption being preferred; after desorbing impurities, the content of impurities such as nitrides and sulfides in the methylated oil is not higher than 30 micrograms / gram, preferably not higher than 10 micrograms / gram.

[0065] According to this disclosure, the extraction unit may include one or more aromatic extraction units; the plurality of aromatic extraction units may be the same or different; the aromatic extraction solvent used for the aromatic extraction may be selected from at least one of plasma solvents, sulfolane, alcohol ethers, pyrrolidones and furfural.

[0066] In this disclosure, the method for separating aromatic hydrocarbons from a mixture of aromatic hydrocarbons is well known to those skilled in the art, and may include one or more of the following: distillation, solvent extraction, adsorption separation, and crystallization separation.

[0067] According to this disclosure, the method may further include: directly introducing the spent catalyst into the regenerator for regeneration, or introducing the spent catalyst into the regenerator after dehydrogenation and depressurization via a catalyst hopper to obtain the regenerated catalyst; directly returning the obtained regenerated catalyst to the turbulent fluidized bed reactor, or returning the obtained regenerated catalyst to the turbulent fluidized bed reactor after deoxygenation and pressurization via a catalyst hopper. In this disclosure, after the spent catalyst is rapidly separated from the oil and gas, it is further stripped with nitrogen via a catalyst hopper to remove flammable gases such as hydrogen and light hydrocarbons entrained in the catalyst, and then enters an oxygen-containing regenerator for regeneration; the obtained regenerated catalyst is again fed into the catalyst hopper system for nitrogen stripping and deoxygenation, and the deoxygenated regenerated catalyst is returned to the reactor. The reactor and regenerator of this disclosure can be arranged in parallel or overlapping, using N2 or other boosting catalysts to circulate between the reactor and the regenerator.

[0068] According to this disclosure, the regeneration conditions may include: a temperature of 500–800°C and a pressure of 0.2–5.0 MPa; preferably, a temperature of 550–700°C and a pressure of 1.0–3.5 MPa. The heat exchange of the regenerated catalyst can be carried out using methods well known to those skilled in the art, thereby controlling the amount of coke generated and the oil-catalyst contact temperature.

[0069] According to this disclosure, the method may further include: recycling the circulating oil obtained in step S2 and / or the raffinate obtained in step S3 back into the refining process.

[0070] According to this disclosure, the catalyst has an average particle size of 40–150 micrometers and an apparent particle density of 0.4–0.9 g / cm³. 3 More preferably, it is 0.8–1.5 g / cm³. 3Based on the weight of the catalyst, the catalyst may include 20-80% by weight of zeolite, 5-30% by weight of inorganic oxides, 10-30% by weight of clay, and 1-20% by weight of active metal; preferably, the catalyst may include 25-75% by weight of zeolite, 10-25% by weight of inorganic oxides, 15-25% by weight of clay, and 5-15% by weight of active metal; the zeolite may be 50-100% by weight of mesoporous zeolite and 0-50% by weight of macroporous zeolite, preferably including 70-90% by weight of mesoporous zeolite and 10-30% by weight of macroporous zeolite; the mesoporous zeolite may be selected from ZSM-5 zeolite, ZSM-11 zeolite, ZSM-12 zeolite, ZSM-23 zeolite, ZSM-35 zeolite, ZSM-23 zeolite, ZSM-35 zeolite, ZSM-12 zeolite, ZSM-23 zeolite, ZSM-23 zeolite, ZSM-24 zeolite, ZSM-25 ... The zeolite comprises one or more of SM-38 zeolite, ZSM-48 zeolite, and ZRP zeolite, wherein the macroporous zeolite can be a Y-series zeolite, specifically one or more selected from REY zeolite, REHY zeolite, ultrastable Y zeolite, high-silica Y zeolite, and β zeolite; the inorganic oxide is silicon dioxide and / or aluminum oxide; on a dry weight basis, silicon dioxide can account for 50-90% by weight and aluminum oxide can account for 10-50% by weight; the clay is selected from one or more of silicon dioxide, kaolin, hydrous kaolin, montmorillonite, diatomaceous earth, halloysite, soapstone, rettosite, sepiolite, attapulgite, hydrotalcite, and bentonite; the active metal is selected from one or more of Group IA, Group IIA, VIA, VIIA, IB, IIB, or transition metal elements.

[0071] One specific implementation of this disclosure is as follows: Figure 1 As shown, in this embodiment, an upward-flowing turbulent fluidized bed reactor is used. Naphthalene-rich hydrocarbon oil 1 and methylating agent 2 undergo a methylation reaction in the fluidized bed reactor using a bottom-feed method. The resulting oil and gas are separated from the catalyst. The process flow is as follows:

[0072] Naphthalene-rich hydrocarbon oil 1 and methylating agent 2 undergo a fluidized bed methylation reaction in a fluidized bed reactor. The fluidized bed reactor introduces a hot regenerator, which has been stripped of oxygen by nitrogen stripping through catalyst hopper system 19, through regenerator feed line I-1. In the fluidized bed reactor, the naphthalene-rich hydrocarbon oil and methylating agent are injected from the first feed oil inlet I-2 at the bottom of the fluidized bed reactor and rise together with the fluidizing medium 3 into the reactor reaction section II, where they undergo a methylation reaction on the hot regenerator. After the reaction, the oil and gas and the catalyst enter the rapid separator III-3 through the reactor transition section III-1 for oil-catalyst separation. The separated catalyst settles into the reactor stripping section III-2, is stripped by stripping medium 4, and exits the reactor through catalyst outlet III-2-1, entering the catalyst hopper system 17. After further nitrogen stripping to remove entrained flammable gas, it enters the regenerator 22 through the regenerator line 20 for regeneration in an oxygen-containing atmosphere at a regeneration temperature of 500-800℃. The regenerated catalyst is then recycled. The separated reaction oil and gas are deeply filtered through filter IV-1 to remove the catalyst, exit the reactor through reaction oil and gas outlet IV-2, and then enter the oil and gas separation system 6 through reaction oil and gas pipeline 5 to obtain gaseous product 7 and methylated oil. The methylated oil is further processed according to its composition and distillation range into light non-aromatic oil 8, BTX-rich light aromatic oil 9, light recycled oil 10, heavy aromatic oil rich in dimethylnaphthalene 11, and heavy recycled oil 12. Light recycled oil 10 is sent to a light aromatic extraction system 13, which includes pretreatment measures such as desulfurization and denitrification, for further aromatic extraction, yielding light aromatics 14 containing benzene, toluene, xylene, etc., and aromatic raffinate oil 15. Heavy aromatic oil 11 is sent to a heavy aromatic separation system 16, which includes pretreatment measures such as desulfurization and denitrification, for further aromatic separation, yielding dimethylnaphthalene 17 and heavy aromatic raffinate oil 18. Aromatic raffinate oils 15 and 18, as well as light non-aromatic oil 8, light circulating oil 10, and heavy circulating oil 12, can be recycled or not recycled depending on product needs. In order to meet the needs of producing more light aromatics and other chemical feedstocks and to meet the self-heating balance of the unit, recycling is the preferred option.

[0073] In this embodiment, the naphthalene-rich hydrocarbon oil 1 mainly refers to the light cycle oil directly from the catalytic cracking unit and / or the naphthalene-rich hydrocarbon oil from other units, such as coal tar; the light non-aromatic oil 8 after product separation and / or the light cycle oil 10 containing naphthalene, methylnaphthalene and other aromatics can be mixed with the naphthalene-rich hydrocarbon oil 1 for feeding, preferably fed upstream of the naphthalene-rich hydrocarbon oil 1, and preferentially contacted with the catalyst; the aromatic raffinate oils 15 and 18 and the heavy cycle oil 12 can be mixed with the naphthalene-rich hydrocarbon oil 1 for feeding, preferably fed downstream of the naphthalene-rich hydrocarbon oil 1.

[0074] The second specific implementation of this disclosure, such as Figure 2As shown, this embodiment uses an upward-flowing turbulent fluidized bed reactor. The naphthalene-rich hydrocarbon oil 1 first enters the oil-gas separation system 6 for fractionation. The resulting light circulating oil fraction 10, rich in naphthalene and methylnaphthalene, undergoes a methylation reaction with the methylating agent 2 in the fluidized bed reactor using a bottom-feed method. The resulting oil and gas are then separated from the catalyst. The process flow is as follows:

[0075] Naphthalene-rich hydrocarbon oil 1 first undergoes heat exchange before entering the oil-gas separation system 6 for fractionation. The resulting light circulating oil fraction 10, rich in naphthalene and methylnaphthalene, undergoes a fluidized bed methylation reaction with methylating agent 2 in a fluidized bed reactor. The fluidized bed reactor is supplied with a regenerator that has undergone nitrogen stripping to remove oxygen via the catalyst hopper system 19 through the regenerator feed line I-1. In the fluidized bed reactor, the naphthalene-rich hydrocarbon oil and methylating agent are injected from the first feed oil inlet I-2 at the bottom of the fluidized bed reactor, and rise together with the fluidizing medium 3 into the reactor reaction section II. The reaction involves methylation on a hot regenerator. After the reaction, the oil and gas, along with the catalyst, pass through the reactor transition section III-1 and enter the rapid separator III-3 for oil-catalyst separation. The separated catalyst settles into the reactor stripping section III-2, is stripped by stripping medium 4, and exits the reactor through catalyst outlet III-2-1. It then enters the catalyst hopper system 17 for further nitrogen stripping to remove entrained flammable gases. After this, it enters the regenerator 22 via the regenerator pipeline 20 for regeneration in an oxygen-containing atmosphere at a regeneration temperature of 500-800℃. The regenerated catalyst is then recycled. Meanwhile, the separated reaction oil and gas undergoes deep filtration through filter IV-1 to remove any entrained catalyst. It exits the reactor through reaction oil and gas outlet IV-2 and then enters the oil and gas separation system 6 via reaction oil and gas pipeline 5 to obtain gaseous product 7 and methylated oil. Based on their composition and distillation range, the methylated oil is further divided into light non-aromatic oil 8, BTX-rich light aromatic oil 9, light recycle oil 10, heavy aromatic oil rich in dimethylnaphthalene 11, and heavy recycle oil 12. Light recycle oil 10 is fed into a light aromatic extraction system 13, which includes pretreatment measures such as desulfurization and denitrification, for further aromatic extraction, yielding light aromatics 14 containing benzene, toluene, xylene, etc., and aromatic raffinate oil 15. Heavy aromatic oil 11 is fed into a heavy aromatic separation system 16, which includes pretreatment measures such as desulfurization and denitrification, for further aromatic separation, yielding dimethylnaphthalene 17 and heavy aromatic raffinate oil 18. Aromatic raffinate oils 15 and 18, as well as light non-aromatic oil 8, light recycle oil 10, and heavy recycle oil 12, can be recycled or not recycled depending on product requirements. Recycling is preferred due to the need for increased production of light aromatics and other chemical feedstocks, and to meet the unit's self-heating balance requirements.

[0076] In this embodiment, the naphthalene-rich hydrocarbon oil 1 mainly refers to the light cycle oil directly from the catalytic cracking unit and / or the naphthalene-rich hydrocarbon oil such as coal tar from other units. It first enters the oil-gas separation system for fractionation after heat exchange to remove dimethylnaphthalene contained in the hydrocarbon oil. The light cycle oil 10 containing naphthalene, methylnaphthalene and other aromatics then undergoes a methylation reaction with the methylating agent 2. The light non-aromatic oil 8 obtained from product separation can be mixed with the light cycle oil 10 containing naphthalene, methylnaphthalene and other aromatics and fed into the system. It is preferred to feed the naphthalene-rich hydrocarbon oil 10 upstream and to contact the catalyst. The aromatic raffinate oils 15 and 18 and the heavy cycle oil 12 can be mixed with the naphthalene-rich hydrocarbon oil 10 and fed into the system. It is preferred to feed the naphthalene-rich hydrocarbon oil 10 downstream.

[0077] The present disclosure is further described in detail below through examples. All raw materials used in the examples are commercially available.

[0078] The raw materials used in the examples are catalytic cracking light cycle oils, the properties of which are shown in Table 1.

[0079] The catalysts used in the examples are the same, and their preparation methods are briefly described below:

[0080] 1) Dissolve 10 kg of NH4Cl in 500 kg of water, add 50 kg (dry basis) of crystallized DASY zeolite (produced by Qilu Petrochemical Company Catalyst Plant, 2.445-2.448 nm, rare earth content RE2O3 = 2.0 wt%) to this solution, exchange at 90℃ for 0.5 h, and filter to obtain filter cake; add 94.0 kg of Cu(NO3)2·3H2O dissolved in 261 kg of water, mix with filter cake, impregnate and dry; then calcine at 550℃ for 2 hours to obtain copper-containing macroporous zeolite, whose elemental analysis chemical composition is 0.1Na2O·5.1Al2O3·72.6Cr2O3·3.8RE2O3·88.1SiO2.

[0081] 2) Use 250kg of decationized water to slurry 37.7kg of hydrous kaolin (an industrial product of Suzhou Porcelain Clay Company, solid content 71.6m%), then add 27.4kg of pseudoboehmite (an industrial product of Shandong Aluminum Plant, solid content 63m%), adjust the pH to 2-4 with hydrochloric acid, stir evenly, let it stand and age at 60-70℃ for 1 hour, keeping the pH at 2-4, then lower the temperature to below 60℃, add 20.8kg of aluminum sol (a product of Qilu Petrochemical Company Catalyst Plant, Al2O3 content 21.7m%), stir for 40 minutes to obtain a mixed slurry.

[0082] 3) The copper-containing macroporous zeolite (16.9 kg dry basis) prepared in step 1) and the MFI-structured mesoporous ZRP-1 zeolite (industrial product of Qilu Petrochemical Company Catalyst Plant, SiO2 / Al2O3 = 30, phosphorus content P2O5 = 3.5 wt%, 39.8 kg dry basis) were added to the mixed slurry obtained in step 2), stirred evenly, and then special binder, structural aid and pore-forming agent were added. After mixing, the mixture was placed in a bonding machine, an appropriate amount of water was added, and the mixture was stirred evenly. After being placed in air for 4 hours, it was spray-dried and shaped. After drying in a drying oven at 120℃ for 3 hours, it was washed with ammonium dihydrogen phosphate solution (phosphorus content 1 m%) to remove free Na. + Washing removes free Na + The catalyst, CAT-1, was obtained by further drying. The catalyst consisted of 9.5 wt% copper oxide, 36.1 wt% MFI mesoporous zeolite, 12.7 wt% DASY zeolite, 15.3 wt% pseudoboehmite, 4.0 wt% alumina sol, and the balance kaolin. Its properties are listed in Table 2.

[0083] Example 1

[0084] This embodiment follows Figure 1 The process was tested using a mixture of catalytic cracking light cycle oil A and methanol C (as shown in Table 1) at an alcohol / naphthalene molar ratio of 0.5 as feedstock. The experiment was conducted in a fluidized bed reactor using CAT-1 catalyst. For the first start-up of the catalyst, activation was performed at 500°C for 2 hours under nitrogen flow. The mixed feedstock of catalytic cracking light cycle oil A and methanol B, preheated to 240°C, entered the bottom of the fluidized bed reactor. At a reaction pressure of 0.2 MPa and a N2 (as fluidizing medium) / naphthalene molar ratio of 0.01, the fluidizing medium flowed upwards. The reaction temperature was 520°C, the catalyst-to-feedstock weight ratio was 3.0, and the weight hourly space velocity (WHSV) was 9.9 h⁻¹. -1 Methylation reaction is carried out under the following conditions: the reaction oil and gas are separated into gaseous products and methylated oil by a separation system. The methylated oil is desulfurized and nitrogenized, and then subjected to aromatic extraction to obtain high-value aromatics such as benzene, toluene, xylene, and dimethylnaphthalene. The aromatic residue oil, C5-60℃ light non-aromatic oil, 150-250℃ light cycle oil components rich in naphthalene and methylnaphthalene, and heavy cycle oil components above 280℃ are all recycled. After the reaction, the spent catalyst is stripped with nitrogen to remove the oil and gas adsorbed inside, and then further stripped through the catalyst hopper system before being sent to the regenerator. Air is used as the regeneration gas, and the catalyst is regenerated at a regeneration temperature of 550-700℃. The regenerated catalyst is recycled. The operating conditions and product distribution are listed in Table 3.

[0085] As shown in Table 3, in Example 1, the FCC circulating oil rich in naphthalene and methylnaphthalene reacted with methanol in a fluidized bed reactor, resulting in a dimethylnaphthalene yield of 7.57 wt%, a BTX (benzene + toluene + xylene) yield of 6.62 wt%, and a triene (ethylene + propylene + butene) yield of 8.46 wt%. The total yield of high-value chemical materials such as triene, BTX, and dimethylnaphthalene was 22.65 wt%.

[0086] Comparative Example 1

[0087] The methylation reaction was carried out using the same feedstock, catalyst, and process conditions as in Example 1, with the following differences: Example 1 used a fixed-bed reactor, and the reaction was conducted in an externally heated, isothermal reactor with no temperature difference; the coking catalyst reaction and regeneration were carried out alternately in one unit; to maintain reaction stability and reduce coking, the fixed-bed reactor could not recycle aromatic raffinate, C5-60°C light non-aromatic oil, or heavy cycle oil components above 280°C. It could only recycle light cycle oil components rich in naphthalene and methylnaphthalene at 150-250°C mixed with catalytic cracking light cycle oil A. Operating conditions and product distribution are listed in Table 3.

[0088] As can be seen from Table 3, compared with Comparative Example 1 (Fixed Bed Reactor), Example 1 (fluidized bed reactor) has a higher yield of dimethylnaphthalene, which is 3.42 percentage points higher than Comparative Example 1; moreover, the yield of high-value chemical products is higher, and the total yield of high-value chemical products such as triene + BTX + dimethylnaphthalene is 10.23 percentage points higher than Comparative Example 1.

[0089] Example 2

[0090] This embodiment follows Figure 2 The process was tested using catalytic cracking light cycle oil B and ethanol D as feedstocks (Table 1), in a fluidized bed reactor with CAT-1 catalyst. For the first start-up of the catalyst, activation was performed at 500℃ for 2 hours under nitrogen flow. After heat exchange at 300℃, catalytic cracking light cycle oil B entered the oil-gas separation system 6 for fractionation. The resulting 170–250℃ light cycle oil fraction 10, rich in naphthalene and methylnaphthalene, was mixed with ethanol D at an alcohol / oil mass ratio of 0.01. This mixed feedstock oil was preheated at 240℃ and then entered the bottom of the fluidized bed reactor. Under a reaction pressure of 0.2 MPa and a N2 (as fluidizing medium) / mixed feedstock oil volume ratio of 30, the fluidizing medium flowed upwards. The reaction was carried out at a reaction temperature of 480℃, a catalyst-to-feedstock oil weight ratio of 1.0, and a weight hourly space velocity of 5.0 h⁻¹. -1Methylation reaction is carried out under the following conditions; the reaction oil and gas are separated into gaseous products and methylated oil by a separation system. The methylated oil is desulfurized and nitrogenized, and then subjected to aromatic extraction to obtain high-value aromatics such as benzene, toluene, xylene, and dimethylnaphthalene. The aromatic residue oil, light non-aromatic oil with C5-60℃, and heavy recycled oil components with temperatures above 280℃ are all recycled. After the reaction, the spent catalyst is stripped with nitrogen to remove the oil and gas adsorbed inside, and then further stripped through the catalyst hopper system before being sent to the regenerator. Air is used as the regeneration gas, and the catalyst is regenerated at a regeneration temperature of 550-700℃. The regenerated catalyst is recycled. The operating conditions and product distribution are listed in Table 3.

[0091] As shown in Table 3, in Example 1, after the catalytic cracking cycle oil was fractionated, the light cycle oil rich in naphthalene and methylnaphthalene reacted with ethanol in a fluidized bed reactor for methylation. The yield of dimethylnaphthalene was 41.61 wt%, the yield of BTX (benzene + toluene + xylene) was 4.82 wt%, and the yield of triene (ethylene + propylene + butene) was 6.41 wt%. The total yield of high-value chemical materials such as triene + BTX + dimethylnaphthalene was 52.84 wt%.

[0092] Table 1

[0093] Crude oil name Catalytic cracking light cycle oil Catalytic cracking light cycle oil Industrial methanol Industrial ethanol Raw material oil number A B C D <![CDATA[Density, kg / m 3 > 919.6 972.6 790 790 Purity, weight % - - 99.9 99.5 Naphthalene compounds in the composition Naphthalene, weight % 3.98 2.80 - Methylnaphthalene, weight % 19.70 10.24 - Dimethylnaphthalene, weight % 0.88 39.65 - 2,6-Dimethylnaphthalene 0.15 9.77 Distillation range, °C Initial boiling point 200 200 10％ 208 220 50％ 230 266 90％ 254 330 Final boiling point 273 350

[0094] Table 2

[0095] Catalyst number CAT-1 Chemical composition, weight % copper oxide 9.52 Rare earth 0.25 Phosphorus pentoxide 1.26 Sodium oxide 0.12 Alumina 42.24 silicon dioxide 46.61 <![CDATA[Apparent density, kg / m 3 > 870 Pore ​​volume, ml / g 0.21 <![CDATA[Specific surface area, m 2 / g]]> 185 <![CDATA[Wear index, % by weight -1 > 1.1 Sieving composition, weight % 0–40 micrometers 12.6 40–100 micrometers 60.2 100-150 micrometers 27.2

[0096] Table 3

[0097] Example 1 Comparative Example 1 Example 2 crude oil A+C A+C B+D Reactor type fluidized bed Fixed bed fluidized bed Catalyst name CAT-1 CAT-1 CAT-1 Reaction operating conditions Reaction pressure, MPa 0.2 0.2 0.2 Reactor inlet temperature, °C 580 520 550 Temperature in the middle of the reactor, °C 540 520 510 Reactor outlet temperature, °C 520 520 480 Catalyst / feedstock weight ratio 3.0 3.0 1.0 <![CDATA[Heavy space velocity, h -1 > 9.9 9.9 5.0 Product yield, by weight % gas 22.31 12.23 16.32 Triene 8.46 4.64 6.41 Alkanes 13.85 7.59 9.82 Methylated oil 72.98 85.19 82.04 Among them BTX 6.62 3.63 4.82 dimethylnaphthalene 7.57 4.15 41.61 coke 4.71 2.58 1.64 total 100.00 100.00 100.00 Triene + BTX + DMN yield, wt% 22.75 12.42 52.84

[0098] The preferred embodiments of this disclosure have been described in detail above. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0099] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0100] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A method for producing dimethylnaphthalene using a fluidized bed reactor, the method comprising: S1. The hydrocarbon oil rich in naphthalene compounds is mixed with a methylating agent and introduced into a turbulent fluidized bed reactor to contact the catalyst and carry out a methylation reaction in the presence of a fluidized medium. The resulting oil is separated to obtain the catalyst to be generated and the methylated oil. S2. Separate the methylated oil to obtain reaction gas, naphthalene-containing aromatic oil, and recycled oil containing non-aromatic hydrocarbons and / or naphthalene and methylnaphthalene fractions; S3. After desulfurization and denitrogenation, the naphthalene-containing aromatic oil is extracted by an extraction unit to obtain an aromatic mixture; the aromatic mixture is then separated to obtain BTX monocyclic aromatic hydrocarbons, dimethylnaphthalene, and raffinate. S4. The catalyst to be generated is introduced into a regenerator for regeneration to obtain a regenerated catalyst, and the regenerated catalyst is returned to the turbulent fluidized bed reactor. The naphthalene-rich hydrocarbon oil is selected from one or more of the following: catalytic cracking light cycle oil with a boiling point of 160-340℃, coal tar, distillate oil rich in naphthalene and methylnaphthalene from other units, pure naphthalene hydrocarbon oil, and methylnaphthalene hydrocarbon oil. Based on the weight of the catalyst, the catalyst comprises 20-80% by weight of zeolite, 5-30% by weight of inorganic oxide, 10-30% by weight of clay and 1-20% by weight of active metal; the zeolite comprises 70-90% by weight of mesoporous zeolite and 10-30% by weight of macroporous zeolite.

2. The method according to claim 1, wherein, The other apparatus is selected from one or more of ethylene plants, hydrocracking and coking plants; The naphthalene-rich hydrocarbon oil contains 10-90% naphthalene by weight.

3. The method according to claim 1, wherein, The molar ratio of the methylating agent to the naphthalene-rich hydrocarbon oil is 0.1 to 10; The methylating agent includes low-carbon alcohols and / or polymethylbenzenes; The lower alcohol is selected from at least one of methanol, ethanol, and isopropanol; The polymethylbenzene is selected from at least one of tetramethylbenzene, pentamethylbenzene, and hexamethylbenzene.

4. The method according to claim 3, wherein, The molar ratio of the methylating agent to the naphthalene-rich hydrocarbon oil is 0.5 to 5.

0.

5. The method according to claim 1, wherein, The fluidizing medium is selected from hydrogen-containing gases and / or hydrogen-free gases.

6. The method according to claim 5, wherein, The hydrogen-containing gas is hydrogen or dry gas, and the hydrogen-free gas is nitrogen and / or water vapor.

7. The method according to claim 1, wherein, The conditions for the methylation reaction include: a reaction temperature of 300–600 °C; a reaction pressure of 0.2–2.0 MPa; a reaction time of 0.1–20 seconds; and a weight hourly space velocity of 0.1–20 h⁻¹. -1 The weight ratio of the agent to oil is 0.1-10.

8. The method according to claim 7, wherein, The reaction temperature is 400~550℃; the reaction pressure is 0.5~1.5 MPa; the reaction time is 1~10 seconds; and the weight hourly space velocity is 1.0-15 h⁻¹. -1 The weight ratio of the agent to oil is 1-8.

9. The method according to claim 1, wherein, The turbulent fluidized bed reactor is a fluidized bed and / or a riser reactor; The apparent average linear velocity of oil and gas in the turbulent fluidized bed reactor is 0.5-2.0 m / s.

10. The method according to claim 1, wherein, The extraction unit includes one or more aromatic hydrocarbon extraction units; the plurality of aromatic hydrocarbon extraction units may be the same or different. The aromatic extraction solvent used for aromatic extraction is selected from at least one of plasma solvents, sulfolane, alcohol ethers, pyrrolidones, and furfural.

11. The method according to claim 1, wherein, The method further includes: The spent catalyst is directly introduced into the regenerator for regeneration, or the spent catalyst is dehydrogenated and depressurized in the catalyst hopper and then introduced into the regenerator for regeneration to obtain the regenerated catalyst; The obtained regenerated catalyst is either directly returned to the turbulent fluidized bed reactor or deoxygenated and pressurized in the catalyst hopper before being returned to the turbulent fluidized bed reactor.

12. The method according to claim 11, wherein, The regeneration conditions include a temperature of 500~800℃ and a pressure of 0.2~5.0MPa.

13. The method according to claim 12, wherein, Temperature is 550~700℃, pressure is 1.0~3.5MPa.

14. The method according to claim 1, wherein, The method further includes: recycling the circulating oil obtained in step S2 and / or the raffinate obtained in step S3 back into the refining process.

15. The method according to claim 1, wherein, The catalyst has an average particle size of 40-150 micrometers; The catalyst comprises 25-75% by weight zeolite, 10-25% by weight inorganic oxides, 15-25% by weight clay, and 5-15% by weight active metal. The mesoporous zeolite is selected from one or more of ZSM-5 zeolite, ZSM-11 zeolite, ZSM-12 zeolite, ZSM-23 zeolite, ZSM-35 zeolite, ZSM-38 zeolite, ZSM-48 zeolite and ZRP zeolite, and the macroporous zeolite is selected from one or more of REY zeolite, REHY zeolite, ultrastable Y zeolite and high silica Y zeolite and β zeolite; The inorganic oxide is silicon oxide and / or aluminum oxide; The clay is selected from one or more of the following: silica, kaolin, hydrous kaolin, montmorillonite, diatomite, halloysite, soapstone, rettoite, sepiolite, attapulgite, hydrotalcite, and bentonite. The active metal is selected from one or more elements from Group IA, Group IIA, VIA, VIIA, Group IB, IIB, or transition metals.

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