CN117658757A

CN117658757A - Alkylation reaction method of aromatic hydrocarbon and long-chain olefin

Info

Publication number: CN117658757A
Application number: CN202211054498.0A
Authority: CN
Inventors: 任奎; 李永祥; 张成喜; 周顺利; 付强; 邢恩会
Original assignee: Sinopec Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Current assignee: Sinopec Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2022-08-31
Filing date: 2022-08-31
Publication date: 2024-03-08

Abstract

An alkylation reaction method of aromatic hydrocarbon and long-chain olefin is to make raw material aromatic hydrocarbon and raw material long-chain olefin contact reaction under alkylation reaction condition, characterized by that, the method uses solid acid loaded with metal with hydrogenolysis property as catalyst, including stopping raw material aromatic hydrocarbon and raw material long-chain olefin feeding periodically and using an aromatic hydrocarbon substance to contact catalyst in the period that conversion rate of raw material long-chain olefin is greater than or equal to 99%; and a step II of contacting the catalyst with hydrogen when the conversion rate of the long-chain olefin is less than 99%.

Description

Alkylation reaction method of aromatic hydrocarbon and long-chain olefin

Technical Field

The invention relates to a solid acid alkylation reaction method, in particular to an alkylation reaction method for preparing straight-chain alkyl aromatic hydrocarbon by taking solid acid as a catalyst and aromatic hydrocarbon and long-chain olefin as raw materials.

Background

The linear alkylbenzene obtained by alkylation reaction of benzene and long-chain olefin is an important chemical intermediate for synthesizing various washing products, and the intermediate can obtain an anionic surfactant-alkylbenzene sulfonate with excellent performance after sulfonation, neutralization and other reactions. The reaction starts in the forty of the twentieth century and lays a foundation for the industry of synthetic detergents.

At present, 83% of the global linear alkylbenzene yield adopts an HF process, and 9% adopts AlCl ₃ The process, 8% employs the Detal process. HF process and AlCl ₃ The process has various defects of high environmental pollution, serious equipment corrosion, difficult product separation, large cost investment and the like.

The Detal process is a solid acid process developed by the UOP company in the United states and CEPSA Petroleum company in Spain, and has been industrialized in the middle of the nineties of the last century. Because the Detal process adopts the fluorine-containing amorphous silica-alumina catalyst, the problems of fluorine loss, discontinuous alkylation reaction and catalyst regeneration process, high operation cost, frequent regeneration and the like exist in the process operation process, so the popularization and development of the catalyst are limited to a certain extent.

The development of green and environment-friendly solid acid alkylation technology is a future development trend. The synthesis of linear alkylbenzenes by alkylation of benzene with long-chain olefins catalyzed by solid acids has been studied by the universities of petrochemical industry, the universities of eastern China, the south Beijing alkylbenzene works, the universities of China, the institute of chemical and physical, and the like, and molecular sieves and heteropolyacid type solid acid catalysts are mostly adopted. Because the problems of easy deactivation and short single-cycle life of the solid acid catalyst are not solved effectively, the development of the process technology of the green solid acid catalyst which operates stably for a long time and is easy to regenerate has important economic and social benefits.

In order to improve the single cycle life of the solid acid catalyst in the reaction and prolong the stable operation time, many researches are focused on synthesizing catalytic materials or optimizing the process from the flow point of view; for the regeneration of the solid acid catalyst, a solvent elution mode is often adopted. The problems of poor reaction effect of the catalytic material, frequent operation of the regeneration process flow, high cost and the like generally exist.

CN1043524C discloses a process for benzene alkylation with fluorinated silica alumina and linear mono-olefins by contacting benzene and linear mono-olefins under alkylation conditions with a catalyst comprising silica to alumina in a weight ratio of 1:1 to 9:1 and a fluorinated silica alumina content of 1 to 6wt%, using C ₆ To C ₂₀ The linear mono-olefins alkylate benzene with 98% conversion of olefins, selectivity to mono-alkylbenzenes of 85% or better and linearity with respect to mono-alkylbenzenes produced of at least 90%. However, the method has the problems of low conversion rate of olefin and environmental pollution caused by fluoride ion loss.

CN101535221a discloses a process for the preparation of alkylbenzenes with low benzene to olefin ratio and low heavies formation over a solid acid catalyst, in which small crystal, acidic FAU molecular sieves are used as catalysts.

CN111514924a discloses a catalytic synthesis method of long-chain alkyl aromatic hydrocarbon, which comprises: firstly, inputting raw aromatic hydrocarbon into a fixed bed alkylation reactor, and filling the reactor; then the raw material arene and the raw material C ₆ ～C ₂₄ Inputting long-chain olefin and an additive long-chain alkyl aromatic hydrocarbon solvent or a mixture of long-chain alkane solvents into a fixed bed reactor, contacting with SBA-15 type mesoporous molecular sieve alkylation solid acid catalyst, and carrying out alkylation reaction of aromatic hydrocarbon and long-chain olefin to generate a product long-chain alkyl aromatic hydrocarbon; a portion of the alkylation reactor effluent is used as the recycle stream to the reactor and another portion is passed to a distillation separation system to separate the effluent stream of the excess feedstock and product.

US5648579a discloses a process for alkylation of benzene with 1-dodecene using a pulse feed. Benzene in the raw materials of the method is always fed, and 1-dodecaalkene is stopped at intervals, so that pulse feeding is realized, the mole ratio of benzene to alkene is between 8 and 20, the carbon number of straight-chain alkene is between 10 and 14, and the interval time of pulse feeding is between 10 and 60 minutes.

Disclosure of Invention

The inventor finds that after the alkylation reaction of the aromatic hydrocarbon and the long-chain olefin is carried out for a certain time, the solid acid catalyst loaded with the metal with hydrogenolysis performance is treated under the hydrogen atmosphere, and then the step of flushing the solid acid catalyst by the aromatic hydrocarbon substances under proper time and condition is assisted, so that the alkylation activity of the solid acid catalyst can be completely recovered, the stable operation time of the solid acid catalyst in a reaction-regeneration mode is greatly improved, and the high selectivity of the linear aromatic hydrocarbon product is maintained. Based on this, the present invention is formed.

It is therefore an object of the present invention to provide a process for alkylation of aromatic hydrocarbons with long chain olefins which is distinguished from the prior art and which not only allows for an extended catalyst single cycle life and product selectivity, but also ensures a long cycle stable operation of the reaction unit.

In order to achieve the above object, the present invention provides a process for alkylation of aromatic hydrocarbon and long-chain olefin, comprising the steps of contacting a raw material aromatic hydrocarbon and a raw material long-chain olefin under alkylation conditions, wherein the process comprises the step of periodically stopping the feed of the raw material aromatic hydrocarbon and the raw material long-chain olefin and contacting the solid acid with an aromatic hydrocarbon substance during a period in which the conversion rate of the raw material long-chain olefin is not less than 99% by using a solid acid loaded with a metal having hydrogenolysis property as a catalyst; and a step II of contacting the solid acid with hydrogen when the conversion rate of the raw material long-chain olefin is less than 99%.

In the invention, the alkylation reaction condition is that the temperature is 70-280 ℃, the pressure is 1.5-5 MPa, and the mass airspeed of the raw materials including the raw material arene and the raw material long-chain alkene is 1-20. The mol ratio of the raw material arene to the raw material long-chain olefin is 5-100:1.

in the invention, the solid acid contains 20-95 wt% of molecular sieve and 5-80 wt% of inorganic oxide. Wherein the molecular sieve is one or more of FAU, MWW, MOR, BEA type topological structures, preferably FAU type topological structure molecular sieve, more preferably Y molecular sieve.

It is found that the deactivation of the alkylation reaction of aromatic hydrocarbon and long-chain olefin is caused by the blockage of catalyst pore channels by heavy alkyl aromatic hydrocarbon generated in the reaction process, and the reaction can be catalyzed by B acid or L acid, so that the proper control of the unit cell of the catalyst can ensure the integrity of the crystal structure of the catalyst and ensure that the reaction has enough active center of B acid. Thus, the Y-type zeolite of the present invention has a unit cell of 2.448 to 2.457nm, preferably a unit cell of 2.452 to 2.455nm.

According to the invention, further research shows that since the heavy alkyl aromatic hydrocarbon is a key for causing the deactivation of the catalyst, the mesoporous with a specific proportion can promote the timely diffusion of macromolecules such as the heavy alkyl aromatic hydrocarbon from the pore canal and delay the coking of the catalyst. The ratio of the mesoporous volume to the total pore volume is 0.15-0.29, preferably the ratio of the mesoporous volume to the total pore volume is 0.18-0.26. The mesoporous volume and total pore volume described in the present invention can be determined by the static low temperature nitrogen adsorption capacity method (BET). BET measurements are well known to those skilled in the art and can be performed, for example, using an ASAP2420 adsorber from America Micyoco, inc., as follows: firstly, drying a sample in an oven at 110 ℃ for 2 hours to remove surface water, then weighing a certain amount of sample, putting the sample into a degassing unit, vacuumizing to a vacuum degree of less than 1.33Pa, treating the sample at 90 ℃ for 1 hour, and then heating the sample to 330 ℃ for 9-10 hours; and (3) carrying out nitrogen adsorption and desorption test on the sample under the condition of liquid nitrogen cooling to obtain an adsorption-desorption curve, and calculating the specific surface area and the pore volume through a BET formula.

The inorganic oxide is selected from one or more of silicon oxide, aluminum oxide, zirconium oxide and titanium oxide.

In the invention, the solid acid Y molecular sieve is loaded with a proper amount of metal with hydrogenolysis performance, has a strong synergistic catalysis effect with the B acid site, and has better alkylation activity and selectivity under the reaction condition of the invention. The metal with hydrogenolysis performance is selected from one or more of VIB, VIIB and VIII metals. Wherein the VIII metal is selected from one or more of Pt, pd and Ru, and the preferable one is Pt, and the Pt can not only generate synergistic action with B acid, but also can be used as a source of partial L acid center to improve the service life of the catalyst. The metal with hydrogenolysis performance accounts for 0.15 to 5 weight percent of the solid acid catalyst, and preferably accounts for 0.2 to 2 weight percent. The solid acid catalyst is prepared by impregnating Y-type zeolite with impregnating solution containing precursor of metal with hydrogenolysis performance, drying, roasting and reducing, and the precursor of Pt can be selected from one or more of chloroplatinic acid, ammonia chloroplatinate, potassium chloroplatinate, platinum tetrachloride or platinum tetrammine nitrate. The noble metal in the solid acid catalyst remains metallic as the alkylation reaction proceeds.

In the present invention, the total carbon number of the raw aromatic hydrocarbon is 6 to 18, preferably 6 to 11, such as benzene, toluene, xylene, diethylbenzene, trimethylbenzene, triethylbenzene, tetramethylbenzene and isomers thereof. The raw aromatic hydrocarbon has a side chain with carbon number of 0-8, preferably 0-4, such as benzene, toluene, xylene, diethylbenzene, trimethylbenzene, triethylbenzene, tetramethylbenzene and isomers thereof. The raw material long-chain olefin comprises C ₁₀ ～C ₁₄ One or more of the long chain olefins such as decene, undecene, dodecene, tridecene, tetradecene and isomers thereof.

In the invention, the step I is carried out after the raw material arene and the raw material long-chain olefin are contacted for alkylation reaction for 5-36 hours, preferably 10-28 hours at intervals in the period that the conversion rate of the raw material long-chain olefin is more than or equal to 99 percent, and the operation of the step I can be carried out for a plurality of times.

Wherein, the composition of the alkylation raw material and the product is analyzed by adopting a gas chromatograph with model 7890A of Agilent company, the model of a chromatographic column is DB-5MS, the temperature programming of a column box is kept at 50 ℃ for 5min,5 ℃/min is raised to 300 ℃, and the temperature is kept for 5min. The detector is a hydrogen ion flame detector (FID), H ₂ The flow rate is 40mL/min, the air flow rate is 400mL/min, N ₂ The tail blow flow was 25mL/min.

The conversion of the long-chain olefin of the raw material is calculated by adopting the following formula:

conversion of long chain olefins: x= ((w) _Oi －w _Of )/w _Oi )×100％

Wherein w is _Oi The mass fraction of the long-chain olefin in the raw materials before reaction; w (w) _Of The mass fraction of the long-chain olefin after the reaction;

to carry out step I, it is necessary to raise the alkylation reaction temperature to the temperature required for step I. The heating rate may be 1 to 20℃per minute, preferably 3 to 15℃per minute, more preferably 5 to 12℃per minute.

In the step I, the aromatic hydrocarbon substance is one or more of monocyclic or polycyclic aromatic hydrocarbon, such as benzene, toluene, xylene, diethylbenzene, trimethylbenzene, triethylbenzene, tetramethylbenzene and isomers thereof. From the standpoint of at least ease of operation, it is preferred that the feed aromatic hydrocarbon be the same as the aromatic hydrocarbon material described in step I, i.e., that the feed of the feed long chain olefin be stopped.

In step I, the aromatic hydrocarbon material is contacted with a solid acid at a temperature of 130 to 350 ℃, preferably 155 to 280 ℃. The mass airspeed of the aromatic hydrocarbon substance is 1-100 h ^-1 Preferably 5 to 60 hours ^-1 . The aromatic hydrocarbon substance is contacted with the solid acid for 1 to 72 hours, preferably 10 to 36 hours, more preferably 15 to 28 hours.

In the invention, the step II is to contact the solid acid catalyst with hydrogen when the conversion rate of the raw material long-chain olefin is less than 99%. The step II can be carried out for a plurality of times. In order to carry out step II, it is also necessary to raise the temperature from the alkylation reaction temperature to the temperature required for step II. The temperature rise rate may be 1 to 20℃per minute, preferably 1 to 15℃per minute, more preferably 1 to 12℃per minute.

In the step II, the solid acid is contacted with hydrogen at a temperature of 150-500 ℃ and a pressure of 0-5 MPa, preferably at a temperature of 250-480 ℃ and a pressure of 1.5-4 MPa, and more preferably at a temperature of 350-450 ℃. The hydrogen flow rate is 1-500 mL/min/g of catalyst, preferably 20-400 mL/min/g of catalyst. The time is 1 to 10 hours, preferably 3 to 8 hours.

The inventor finds that in the alkylation reaction of aromatic hydrocarbon and long-chain olefin catalyzed by solid acid, the deactivation of the solid acid is caused by that macromolecular heavy alkyl aromatic hydrocarbon generated in the reaction process blocks solid acid pore channels, and after the alkylation reaction is carried out for a period of time, the solid acid is treated by aromatic hydrocarbon substances, so that carbon deposition precursors such as macromolecular heavy alkyl aromatic hydrocarbon generated in the solid acid pore channels can be mostly removed to prolong the single cycle life of the catalyst; and the solid acid is deactivated (namely, the conversion rate of long-chain olefin is reduced to less than 99 percent), and then the hydrogen is adopted to treat the solid acid, so that the carbon deposition component in the solid acid can be almost completely removed, and the catalytic activity of the solid acid is recovered. The method provided by the invention adopts the combination of the step I of periodically treating the solid acid by aromatic hydrocarbon substances when the long-chain olefin conversion rate is more than or equal to 99% and the step II of treating the solid acid by hydrogen when the long-chain olefin conversion rate is less than 99% in the stages of different long-chain olefin conversion rates of alkylation reaction.

The inventors have further found that only these two steps are far from sufficient, and that it is necessary to match the operating parameters of step I and step II if it is desired to achieve good LAB selectivity and 2-LAB ratio, and also to substantially increase the solid acid single cycle life and extend the steady operation time of the device. For example, the various operating parameters in step I of treating the solid acid with aromatic hydrocarbon material include the time interval between conducting two adjacent aromatic hydrocarbon material treatments, the rate of rise of the alkylation reaction temperature to the temperature required for step I, the treatment temperature, the pressure, the mass space velocity of the aromatic hydrocarbon material, the aromatic hydrocarbon material treatment time, etc.; for example, the various operating parameters in step II of treating the solid acid with hydrogen include temperature, pressure, rate of rise of the alkylation reaction temperature to the temperature required for step II, hydrogen flow rate, and isothermal treatment time, among others.

Detailed Description

The present invention will be described in detail by way of examples, with the understanding that the embodiments described herein are merely illustrative and explanatory of the invention, and are not intended to limit the scope of the invention.

The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and are understood to encompass values approaching those ranges or values. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and are to be considered as specifically disclosed herein.

Example 1

The raw material arene is benzene, the raw material long-chain olefin is n-dodecene, the solid acid catalyst is prepared by uniformly mixing a Y molecular sieve (purchased from China petrochemical catalyst division) and alumina according to a weight ratio of 4:1 and loading 0.4wt% Pt by an impregnation method, the obtained solid acid catalyst is A1, wherein the unit cell constant of the Y molecular sieve is 2.448nm, and the ratio of the mesoporous volume to the total pore volume is 0.05.

The alkylation reaction was carried out in a fixed bed high pressure microreaction test apparatus. 5g of catalyst is filled in a fixed bed high pressure micro-reaction test device with the inner diameter of 10mm and the length of 1m, the reaction temperature is 120 ℃, the reaction pressure is 3Mpa, and the mass space velocity of raw materials (benzene and n-dodecene) is 7h ^-1 The benzene molar ratio was 40.

The penetration time of the n-dodecene in the alkylation reaction product is used for determining the single cycle life of the solid acid, wherein the single cycle life refers to the total time of the catalyst treatment raw material in the time (h) when the conversion rate of the n-dodecene is more than or equal to 99 percent, and the conversion rate of the n-dodecene is obtained by analyzing the product through gas chromatography and calculating the following formula.

N-dodecene conversion: x= ((w) ₀ －w _p )/w ₀ )×100％

w ₀ The mass fraction of n-dodecene in the raw materials before reaction; w (w) _p The mass fraction of the n-dodecene after the reaction;

when the conversion rate of the n-dodecene is more than or equal to 99%, implementing the scheme of the step I on the solid acid catalyst, wherein the aromatic hydrocarbon substance is benzene until the conversion rate of the n-dodecene is less than 99%, and the specific step I conditions are shown in the table 1.

The procedure of step II was carried out on the solid acid catalyst at n-dodecene conversion < 99% with the specific conditions shown in Table 2.

The alkylation reaction results are shown in Table 3. In Table 3, LAB and 2-LAB represent the selectivity of linear alkylbenzene and 2-LAB in the product. The components in the linear alkylbenzene product were analyzed by an on-line chromatograph (GC-7890B of agilent).

Comparative example 1

This comparative example is identical to example 1, except that step I and step II of example 1 are not employed.

The alkylation reaction results are shown in Table 3.

Comparative example 2

This comparative example is identical to example I, except that step II of example 1 is not employed.

The specific conditions in step I are shown in Table 1, and the alkylation reaction results are shown in Table 3.

Comparative example 3

This comparative example is identical to example 1, except that step I of example 1 is not employed.

The specific conditions in step II are shown in Table 2, and the alkylation reaction results are shown in Table 3.

Example 2

In this example, the alkylation reaction conditions and step II are the same as in example 1, except that the operating parameters of step I are not the most preferred conditions.

The specific conditions of the step I are shown in Table 1, the specific conditions of the step II are shown in Table 2, and the alkylation reaction results are shown in Table 3.

Example 3

In this example, the alkylation reaction conditions and step I are the same as in example 1, except that the operating parameters of step II are not the most preferred conditions.

TABLE 1

TABLE 2

TABLE 3 Table 3

From the results data in table 3, it can be seen that:

(1) The method of the embodiment 1 of the invention has the best effect of benzene and n-dodecene alkylation reaction, which is obviously better than that of the comparative example 1 which adopts neither the step I nor the step II;

(2) Comparative example 2, which employed only step I, and comparative example 3, which employed only step II, did not perform as well as example 1.

(3) Even if both step I and step II are employed, the alkylation reaction is much less effective than example 1 if one of the operating parameters selected in step I or step II has an example 2 and example 3 that are not within the preferred ranges.

Example 4

The difference between the values of the constant cells 2.453nm and the mesoporous/total pore values 0.22 for the Y molecular sieves used was as in example 1. The alkylation reaction results are shown in Table 4.

Example 5

The difference between this example 1 is that the unit cell constant value of the Y molecular sieve used is 2.455nm and the mesopore/total pore value is 0.18. The alkylation reaction results are shown in Table 4.

Example 6

The difference between this example 1 is that the unit cell constant value of the Y molecular sieve used is 2.452nm and the mesopore/total pore value is 0.29. The alkylation reaction results are shown in Table 4.

TABLE 4 Table 4

Claims

1. The alkylation reaction method of arene and long-chain olefin is characterized in that the method takes solid acid loaded with metal with hydrogenolysis performance as catalyst, and comprises the step I of stopping feeding of arene and long-chain olefin at intervals of 5-36 h and contacting an arene substance with the catalyst in the period that the conversion rate of the long-chain olefin is more than or equal to 99%; and a step II of contacting the catalyst with hydrogen when the conversion rate of the long-chain olefin is less than 99%.

2. The process according to claim 1, wherein the alkylation reaction conditions are such that the temperature is 70 to 280 ℃, the pressure is 1.5 to 5MPa, and the mass space velocity of the feedstock is 1 to 20, and the feedstock comprises a feedstock aromatic hydrocarbon and a feedstock long-chain olefin.

3. The method of claim 1, wherein the solid acid comprises 20 to 95wt% molecular sieve and 5 to 80wt% inorganic oxide.

4. A process according to claim 3 wherein the molecular sieve is one or more of the FAU, MWW, MOR, BEA type topologies.

5. The process of claim 4 wherein the FAU-type topology molecular sieve is a Y molecular sieve.

6. The process of claim 5 wherein the Y molecular sieve has a unit cell of 2.448 to 2.457nm and a ratio of mesoporous volume to total pore volume of 0.15 to 0.29.

7. The process of claim 5 wherein the Y molecular sieve has a unit cell of 2.452 to 2.455nm and a ratio of mesoporous volume to total pore volume of 0.18 to 0.26.

8. A method according to claim 3, wherein the inorganic oxide is selected from one or more of silica, alumina, zirconia and titania.

9. The process according to claim 1, wherein the metal having hydrogenolytic properties is selected from one or more of the metals of groups VIB, VIIB and VIII.

10. The method of claim 1 wherein the metal having hydrogenolytic properties is selected from one or more of the group VIII metals.

11. The method of claim 1, wherein the metal having hydrogenolytic properties is selected from one or more of Pt, pd and Ru.

12. The process according to claim 1, wherein the starting aromatic hydrocarbon has a total carbon number of 6 to 18, preferably 6 to 12.

13. The process according to claim 1, wherein the starting aromatic hydrocarbon has a side chain carbon number of 0 to 8, preferably 0 to 6.

14. The process of claim 1 wherein the feed aromatic hydrocarbon is selected from one or more of benzene, toluene, xylene, diethylbenzene, trimethylbenzene, triethylbenzene, tetramethylbenzene and isomers thereof, and the preferred feed aromatic hydrocarbon is benzene.

15. The process of claim 1 wherein said feedstock long chain olefin is a catalyst comprising C ₁₀ ～C ₁₄ The preferred starting long chain olefins are selected from the group consisting of decene, undecene, dodecene, tridecene, tetradecene and isomers thereof.

16. The process according to claim 1, wherein the step I is carried out at intervals of 5 to 36 hours when the raw material arene and the raw material long chain olefin are in contact with the catalyst during the period that the conversion rate of the raw material long chain olefin is more than or equal to 99 percent.

17. The process according to claim 1, wherein the aromatic hydrocarbon material of step I is one or more of monocyclic or polycyclic aromatic hydrocarbons, preferably benzene, toluene, xylene, diethylbenzene, trimethylbenzene, triethylbenzene, tetramethylbenzene and isomers thereof.

18. The process of claim 1 wherein said aromatic hydrocarbon material in step I is the same as said feed aromatic hydrocarbon.

19. The process according to claim 1, wherein in step I, the aromatic substance is contacted with the catalyst at a temperature of 130 to 350 ℃, preferably at a temperature of 155 to 280 ℃.

20. The process according to claim 1, wherein the temperature is increased from the temperature of the alkylation reaction to the temperature of step I at a rate of 1 to 20 ℃/min, preferably at a rate of 1 to 10 ℃/min.

21. The process according to claim 1, wherein in step I in which the aromatic hydrocarbon material is contacted with the catalyst, the space velocity of the aromatic hydrocarbon material is from 1 to 100 hours ^-1 Preferably at a space velocity of 2 to 60 hours ^-1 。

22. The process according to claim 1, wherein in step I, the aromatic hydrocarbon material is contacted with the catalyst for a period of time ranging from 1 to 72 hours, preferably from 5 to 36 hours.

23. The process according to claim 1, wherein in step II, the temperature is 150 to 500 ℃, the pressure is 0 to 5MPa, preferably the temperature is 250 to 480 ℃, the pressure is 1.5 to 4MPa, more preferably the temperature is 350 to 450 ℃.

24. The process according to claim 1, wherein the temperature rise rate from the alkylation reaction temperature to the step II temperature is from 1 to 20 ℃/min, preferably from 1 to 10 ℃/min.

25. The process according to claim 1, wherein in step II, the hydrogen flow is from 1 to 500mL/min/g of catalyst, preferably the hydrogen flow is from 20 to 400mL/min/g of catalyst.

26. The process according to claim 1, wherein the catalyst in step II is contacted with hydrogen for a period of from 1 to 10 hours, preferably for a period of from 3 to 8 hours.

27. According to claim 1The method is characterized in that the step I is carried out after the contact reaction of the raw material arene and the raw material long-chain olefin for 10 to 28 hours, and the conditions are as follows: from the alkylation reaction temperature to the step I temperature, the heating rate is 1-15 ℃/min, the contact temperature of the aromatic hydrocarbon substance and the catalyst is 155-280 ℃, the time is 10-36 h, and the space velocity of the aromatic hydrocarbon substance is 5-60 h ^-1 The method comprises the steps of carrying out a first treatment on the surface of the And step II, from the alkylation reaction to the step II, the temperature rising rate is 1-15 ℃/min, the pressure is 1.5-4 MPa, the hydrogen flow is 20-400 mL/min/g of catalyst, and the constant temperature time for the contact treatment of the catalyst and the hydrogen is 3-8 h.

28. The method according to claim 1 or 26, wherein said steps I and II are performed a plurality of times.