CN111187134A

CN111187134A - Method for preparing paraxylene and co-produced gasoline from methanol and/or dimethyl ether

Info

Publication number: CN111187134A
Application number: CN201811362317.4A
Authority: CN
Inventors: 刘中民; 于政锡; 朱书魁; 杨越
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2018-11-15
Filing date: 2018-11-15
Publication date: 2020-05-22

Abstract

本申请公开了一种由甲醇和/或二甲醚制备对二甲苯联产汽油的方法，属于化学化工领域。所述方法至少包括以下步骤：a)使含有甲醇和/或二甲醚的原料与催化剂接触反应，得到混合物；从所得混合物中分离出含有苯和甲苯的组分、含有C₄烯烃的组分、含有对二甲苯和汽油组分的产物；b)将所述含有苯和甲苯的组分、所述含有C₄烯烃的组分返回步骤a)，与含有甲醇和/或二甲醚的原料共进料反应。根据本申请的方法通过将甲醇和/或二甲醚转化反应产物中的苯、甲苯和C₄烯烃分离并返回继续反应而提高了对二甲苯的选择性和收率，同时改善了低碳馏分的利用率。该方法操作简便灵活，实施可行性强，而且可节约成本，提高生产经济性，具有重要的应用价值。The application discloses a method for preparing para-xylene co-production gasoline from methanol and/or dimethyl ether, which belongs to the field of chemical industry. The method includes at least the following steps: a) contacting and reacting a raw material containing methanol and/or dimethyl ether with a catalyst to obtain a mixture; and separating the components containing benzene and toluene and the components containing C ₄ olefins from the obtained mixture , a product containing p _- xylene and gasoline components; b) returning the components containing benzene and toluene, the components containing C olefins to step a), and the raw materials containing methanol and/or dimethyl ether Co-feed reaction. The process according to the present application increases the selectivity and yield of para-xylene by separating and returning the benzene, toluene and _C4 olefins in the methanol and/or dimethyl ether conversion reaction product to continue the reaction, while improving the low carbon fraction utilization rate. The method is simple and flexible in operation, has strong feasibility in implementation, can save costs, improve production economy, and has important application value.

Description

Method for preparing paraxylene and co-produced gasoline from methanol and/or dimethyl ether

Technical Field

The application relates to a method for preparing paraxylene and coproducing gasoline by methanol and/or dimethyl ether, belonging to the field of chemical engineering.

Background

Para-xylene (PX) is a feedstock for the production of polyesters such as PET (polyethylene terephthalate), PBT (polybutylene terephthalate) and PTT (polytrimethylene terephthalate). The recent mass application of polyesters in the fields of textile clothing, beverage packaging, etc. has driven a rapid increase in the production and consumption of PTA (purified terephthalic acid) and upstream products PX. At present, the PX is mainly obtained from toluene and C obtained by reforming naphtha₉The aromatic hydrocarbon and mixed xylene are used as raw materials and are prepared by disproportionation, isomerization and adsorption separation or cryogenic separation, so that the equipment investment is large and the operation cost is high. Because the content of the paraxylene in the product is controlled by thermodynamics, the paraxylene only accounts for about 20 percent in xylene isomers, the boiling point difference of three xylene isomers is very small, the high-purity paraxylene cannot be obtained by adopting the common distillation technology, and an expensive adsorption separation process is required to be adopted.

The methanol to gasoline process has developed rapidly since the development of the ZSM-5 molecular sieve by Mobil corporation in the 70's 20 th century. Mobil developed a methanol-to-gasoline process with different reactor types, such as fixed bed, fluidized bed, and tubular. US3928483, US 3931349, US 4035430 and US 4579999 disclose fixed bed processes for preparing liquefied gas and gasoline from methanol by a two-stage method, respectively. CN 10186813A discloses a zirconium-containing ZSM-5 molecular sieve catalyst with small crystal grains and a preparation method thereof, the catalyst is applied to the two-stage reaction in the process of preparing gasoline by a synthesis gas two-stage method, and the gasoline yield is high.

C in gasoline produced in traditional methanol-to-gasoline process₁₀₊High content of heavy aromatic hydrocarbon (about 10%), such as tetramethylbenzene, whose melting point is up to 79 deg.C and which is solid at ordinary tempAnd the crystallization of gasoline products is caused, the quality of gasoline is affected, and the negative effect on engines is generated. Therefore, gasoline components produced in the traditional methanol-to-gasoline process can be used for the motor gasoline after being subjected to weight reduction treatment, and the economy is poor. In addition, the gasoline component produced in the traditional methanol-to-gasoline process contains a small amount of paraxylene, and the content of paraxylene in three xylene products only accounts for about 24 percent (thermodynamic equilibrium value), so that a high-purity paraxylene product can be obtained only by adopting an expensive adsorption separation process. Therefore, the development of a method for preparing dimethylbenzene and gasoline with high selectivity by using methanol has very important social and economic significance.

Disclosure of Invention

According to one aspect of the application, a method for preparing paraxylene and gasoline from methanol and/or dimethyl ether is provided, wherein the method comprises the step of converting the methanol and/or dimethyl ether into reaction products containing benzene, toluene and C₄The olefin components are further reacted, so that the yield of the p-xylene is effectively improved.

The method for preparing paraxylene and coproducing gasoline by using methanol and/or dimethyl ether is characterized by at least comprising the following steps:

a) contacting and reacting a raw material containing methanol and/or dimethyl ether with a catalyst to obtain a mixture; separating a fraction containing benzene and toluene, containing C₄A component of olefins, a product containing paraxylene and a gasoline component;

b) the component containing benzene and toluene and the component containing C₄The components of the olefin are returned to step a) to react with the feed co-feed containing methanol and/or dimethyl ether.

In the method, the catalyst contains C₄The olefin components are separated from the mixture and returned to the step a), and aromatization is carried out by continuous reaction to generate p-xylene.

Optionally, the weight percentage of methanol in the feedstock containing methanol and/or dimethyl ether is greater than or equal to 80 wt%, preferably greater than or equal to 85 wt%, more preferably greater than or equal to 90 wt%.

Optionally, the weight percentage of benzene and toluene in the benzene and toluene containing component is 80 wt% or more, preferably 85 wt% or more, and more preferably 90 wt% or more.

Optionally, the conditions of the reaction include: the inert gas atmosphere has the reaction temperature of 350-410 ℃, the reaction pressure of 0.3-0.7 MPa and the weight space velocity of methanol and/or dimethyl ether of 1-3 h^-1。

Preferably, the inert gas is selected from at least one of an inert gas and nitrogen; the upper limit of the reaction temperature is selected from 410 ℃, 405 ℃, 400 ℃, 395 ℃, 390 ℃, 385 ℃ and 380 ℃, and the lower limit is selected from 350 ℃, 355 ℃, 360 ℃, 365 ℃, 370 ℃, 375 ℃ and 380 ℃; the upper limit of the reaction pressure is selected from 0.7MPa, 0.65MPa, 0.6MPa, 0.55MPa and 0.5MPa, and the lower limit is selected from 0.3MPa, 0.35MPa, 0.4MPa, 0.45MPa and 0.5 MPa; the upper limit of the weight space velocity of the methanol and/or the dimethyl ether is selected from 3h^-1、2.5h^-1、2h^-1The lower limit is selected from 1h^-1、1.5h^-1、2h^-1。

More preferably, the conditions of the reaction include: nitrogen atmosphere, reaction temperature of 380 ℃, reaction pressure of 0.5MPa, and weight space velocity of methanol and/or dimethyl ether of 2h^-1。

Optionally, the catalyst is selected from at least one of zeolite molecular sieve catalysts modified with metal and silylating agents.

Alternatively, the catalyst is obtained by modifying an HZSM-5 zeolite molecular sieve with a metal and a silylating agent.

Optionally, the metal in the metal modification is selected from one or two of copper, zinc, gallium and lanthanum.

Optionally, the silylating agent is selected from at least one of the compounds having the following formula:

wherein R is₁、R₂、R₃And R₄Each independently selected from C_1-10Alkyl of (C)_1-10Alkoxy group of (2).

Alternatively, R₁、R₂、R₃And R₄At least one of them is selected from C_1-10Alkoxy group of (2).

Alternatively, R₁、R₂、R₃And R₄Each independently selected from C_1-10Alkoxy group of (2).

Optionally, the silylating agent is selected from at least one of tetraethyl silicate and tetramethyl silicate.

Optionally, the method for preparing paraxylene and coproducing gasoline from methanol and/or dimethyl ether at least comprises the following steps:

1) enabling raw materials containing methanol and/or dimethyl ether to contact with a catalyst in a reaction system to react to obtain a mixture;

2) the mixture enters a first separation system and is separated to obtain C₄Components of olefins and C₅₊Preparing components; adding said C₄Returning the components of the olefin to the reaction system;

3) said C is₅₊The components enter a second separation system, and are separated to obtain components containing benzene and toluene and products containing paraxylene and gasoline components; returning the benzene and toluene containing component to the reaction system.

Optionally, the reaction system comprises one reactor or a plurality of reactors connected in series and/or parallel.

Optionally, the reactor is selected from at least one of a fixed bed, a fluidized bed, and a moving bed.

As described above, in the method for preparing paraxylene and gasoline from methanol and/or dimethyl ether according to the present application, methanol is first contacted with a catalyst in a reaction system to react, and benzene, toluene and C separated from the reaction system₄The olefin component returns to the reaction system for further reaction to generate paraxylene, and the reaction product is further separated to obtain paraxylene and gasoline component.

The applicant unexpectedly found that when the methanol and/or dimethyl ether is used for catalyzing the reaction product containing benzene and methyl during the process of preparing the paraxylene and coproducing gasoline from the methanol and/or dimethyl etherThe benzene component is separated and returned to the reaction system to continue the reaction, and the benzene and the toluene in the benzene component can generate the para-xylene, so that the selectivity and the yield of the para-xylene in the product are improved. And, when methanol and/or dimethyl ether is catalytically reacted, the product contains C₄Separating olefin components and returning the olefin components to the reaction system for further reaction, wherein C is₄The olefin can be subjected to aromatization under the same reaction conditions to generate the para-xylene, so that the selectivity and the yield of the para-xylene in the product are further improved.

In the context of the present application, for C₄The order of separating the olefin-containing component from the benzene-and toluene-containing component is not particularly limited, but it is preferable to first separate the C-containing component₄Olefin component, and then separating a component containing benzene and toluene.

In the context of the present application, there is no particular limitation on the structure and form of the first separation system, as long as it enables separation of the C-containing component from the reaction product of the conversion of methanol and/or dimethyl ether₄The components of the olefin.

In the context of the present application, there is no particular limitation in the structure and form of the second separation system, as long as it enables separation of the benzene and toluene-containing components from the methanol and/or dimethyl ether conversion reaction product.

In the context of the present application, for a compound which will contain C₄The manner in which the olefin component and the benzene-and toluene-containing component are returned to the reaction system is not particularly limited, but is preferably carried out in a continuous manner. In one embodiment, the C-containing component is separated from the methanol and/or dimethyl ether conversion reaction product in real time₄Olefin components, benzene and toluene containing components, and are pumped back to the reaction system separately in real time.

According to the application, the catalyst used is an HZSM-5 molecular sieve catalyst modified by combining metal and a silanization reagent, and the main preparation process is as follows:

1) impregnating the HZSM-5 molecular sieve with one or two soluble salt solutions of copper, zinc, gallium, lanthanum and the like, filtering, drying and roasting to prepare a metal modified HZSM-5 molecular sieve catalyst;

2) introducing a mixture containing a silanization reagent into a reactor filled with the metal modified HZSM-5 molecular sieve catalyst at the temperature of 130-500 ℃;

3) heating to over 500 ℃, and roasting for 1-6 hours in an air atmosphere.

Optionally, in the step 1), the concentration of the soluble salt solution is 5-15 wt%, the dipping time is 1-3 hours, the drying temperature is 110-150 ℃, and the roasting is performed at 500-600 ℃ for 2-6 hours.

Optionally, in the step 2), the mixture containing the silylation reagent is a mixture of the silylation reagent and methanol, wherein the weight ratio of the silylation reagent to the methanol is 10: 90-40: 60, and the total weight space velocity of the silylation reagent and the methanol is 0.5-1.5 h^-1The feeding time is 45-225 min.

In one embodiment, the method of preparing the catalyst comprises the steps of:

1) soaking the HZSM-5 zeolite molecular sieve in 10 wt% of one or two soluble salt solution selected from copper, zinc, gallium and lanthanum for 2 hours, then filtering, drying at 120 ℃, and roasting at 550 ℃ for 4 hours to prepare a metal modified HZSM-5 molecular sieve catalyst;

2) at the temperature of 150-450 ℃, the mixture of the silylation reagent and methanol with the weight ratio of 10: 90-40: 60 is added for 1 hour^-1Introducing the total weight space velocity of the catalyst and the feeding time of 45-225 min into a reactor filled with the metal modified HZSM-5 molecular sieve catalyst;

3) the temperature is raised to 550 ℃, and the mixture is roasted for 4 hours in an air atmosphere.

In the context of the present application, C_1-10、C_1-4、C₅₊、C₆₊And the like each represents the number of carbon atoms contained in the compound or group. E.g. C_1-10The alkyl group (b) represents any one of alkyl groups having 1 to 10 carbon atoms; c₅₊The component (A) represents a compound component having 5 or more carbon atoms; c₆₊The chain hydrocarbon means a chain hydrocarbon having 6 or more carbon atoms.

In the context of the present application, the term "alkyl" means a group formed by the loss of any one hydrogen atom from an alkane compound molecule. The alkane compound comprises straight-chain alkane, branched-chain alkane, cycloalkane and cycloalkane with branched chain.

In the context of the present application, the term "alkoxy" means a group formed by the loss of a hydrogen atom from an OH group on an alkyl alcohol compound molecule.

In the context of the present application, the term "gasoline" or "gasoline component" means a component having a number of carbon atoms of not less than 5, such as C, generated in a methanol-to-gasoline process₅、C₆₊Chain hydrocarbons, benzene, toluene, ethylbenzene, meta-xylene, ortho-xylene, C₉Aromatic hydrocarbon, C₁₀₊Aromatic hydrocarbons, but not p-xylene.

The beneficial effects that this application can produce include:

1) the method for preparing the paraxylene and the gasoline by the methanol and/or the dimethyl ether comprises the step of converting the methanol and/or the dimethyl ether into reaction products containing benzene, toluene and C₄Olefin components are separated and returned to the feeding material for continuous reaction, so that the selectivity and the yield of the p-xylene are effectively improved.

2) The application provides a method for preparing paraxylene and co-producing gasoline from methanol and/or dimethyl ether, which leads C to react under the same reaction condition₄The aromatization of olefin is not only beneficial to improving the yield of p-xylene, but also improves the utilization rate of low-carbon fraction.

3) The method for preparing the paraxylene and co-producing gasoline by the methanol and/or the dimethyl ether has the advantages of simple and flexible operation, strong implementation feasibility, cost saving, production economy improvement and important application value.

Drawings

FIG. 1 is a schematic process flow diagram of one embodiment of a method according to the present application.

Detailed Description

The process for preparing paraxylene and coproducing gasoline from methanol and/or dimethyl ether provided by the application is shown as a schematic process flow diagram in figure 1.

Referring to fig. 1, in this embodiment, a feedstock containing methanol and/or dimethyl ether is first fed to a reaction system, and the feedstock containing methanol and/or dimethyl ether is contacted with a catalyst in the reaction system to react, resulting in a mixture a. The mixture A enters a first separation system and is separated to obtain a mixture containing C₄Component of olefins, C₁-C₃Component C of₄Alkane component and C₅₊And (4) components. Will contain C₄The components of the olefin are pumped back to the reaction system to produce para-xylene. C₅₊The components enter a second separation system, and are separated to obtain components containing benzene and toluene and products containing paraxylene and gasoline components. The benzene and toluene containing components were pumped back to the reaction system to produce para-xylene. Finally, separating the paraxylene and other gasoline components.

The present application will be described in detail with reference to examples, but the present application is not limited to these examples.

Unless otherwise specified, the starting materials and reagents in the examples of the present application were purchased commercially, wherein HZSM-5 zeolite molecular sieve raw powder was purchased from catalyst works of southern university and Si/Al ═ 5.

The analysis method in the examples of the present application is as follows:

the composition and content of the product were analyzed by on-line Agilent7890 gas chromatography.

The conversion, selectivity in the examples of the present application are calculated as follows:

EXAMPLE 1 FXHZSM-5 fixed bed catalyst preparation

100g of HZSM-5 zeolite molecular sieve raw powder (Nankai university catalyst factory, Si/Al ═ 5) was calcined at 550 ℃ for 4 hours in an air atmosphere to obtain a HZSM-5 zeolite molecular sieve catalyst, which was named FXHZSM-5.

EXAMPLE 2 FXCuZSM-5 fixed bed catalyst preparation

10g of the FXHZSM-5 catalyst prepared in example 1 were placed in 10 wt% Cu (NO)₃)₂Dipping the solution for 2 hours, drying the solution at 120 ℃ after draining, and then roasting the solution for 4 hours at 550 ℃ in an air atmosphere to prepare the FXCuZSM-5 fixed bed catalyst.

EXAMPLE 3 FXZnZSM-5 fixed bed catalyst preparation

10g of the FXHZSM-5 catalyst prepared in example 1 were placed in 10 wt% Zn (NO)₃)₂Dipping the solution for 2 hours, drying the solution at 120 ℃ after draining, and then roasting the solution for 4 hours under the conditions of air atmosphere and 550 ℃ to prepare the FXZnZSM-5 fixed bed catalyst.

EXAMPLE 4 FXGaZSM-5 fixed bed catalyst preparation

10g of the FXHZSM-5 catalyst prepared in example 1 was placed in 10 wt% Ga (NO)₃)₃Dipping the solution for 2 hours, drying the solution at 120 ℃ after draining, and then roasting the solution for 4 hours at 550 ℃ in an air atmosphere to obtain the FXGaZSM-5 fixed bed catalyst.

EXAMPLE 5 FXLaZSM-5 fixed bed catalyst preparation

10g of the FXHZSM-5 catalyst prepared in example 1 was placed in 10 wt% of La (NO)₃)₃Dipping the solution for 2 hours, drying the solution at 120 ℃ after draining, and then roasting the solution for 4 hours at 550 ℃ in an air atmosphere to prepare the FXLaZSM-5 fixed bed catalyst.

Comparative example 1 methanol reaction catalyst preparation and reaction evaluation (no benzene, toluene and C)₄Olefin is returned to the reaction system for further reaction)

The method is used for preparing the catalyst of the fixed bed for preparing the paraxylene and the gasoline by methanol on line in a micro fixed bed reaction device. The conditions for the on-line preparation of the catalyst were as follows: tabletting and molding the FXCuZSM-5 catalyst prepared in example 2, crushing and screening the obtained product into 40-60 meshes, putting 5g (40-60 meshes) of the catalyst into a fixed bed reactor, treating the obtained product at 550 ℃ for 1 hour by 50ml/min of nitrogen, and then treating the obtained product in nitrogenCooling to 200 ℃ under the atmosphere. Feeding a mixed solution of tetraethyl silicate and methanol by using a trace feed pump, wherein the weight ratio of tetraethyl silicate to methanol is 20:80, and the total weight space velocity of the tetraethyl silicate and the methanol is 1h^-1And normal pressure. Stopping feeding after 90min, blowing by using nitrogen, heating to 550 ℃, and roasting for 4 hours in an air atmosphere to prepare the fixed bed catalyst for co-production of p-xylene and gasoline by using methanol, which is named as FXMTGCAT-1.

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. The reaction product was analyzed by on-line Agilent7890 gas chromatography, and samples were taken for analysis at 60min of reaction. The reaction results are shown in table 1.

TABLE 1

Catalyst and process for preparing same	FXMTGCAT-1
		Reaction temperature (. degree.C.)	380
Methanol conversion (%)	100
		Selectivity (wt%) of p-xylene in xylene product	99.52
Product distribution (wt%)
		CH₄	3.76
C₂H₄	3.99
		C₂H₆	2.30
C₃H₆	3.49
		C₃H₈	12.34
C₄Olefins	5.40
		C₄Alkane(s)	7.11
C₅	6.89
		C₆₊Chain hydrocarbons	3.06
Benzene and its derivatives	2.13
		Toluene	21.38
Ethylbenzene production	1.47
		Para-xylene	24.56
Meta-xylene	0.08
		Ortho-xylene	0.04
C₉Aromatic hydrocarbons	1.79
		C₁₀₊Aromatic hydrocarbons	0.20

		Gasoline component selectivity (wt%) in hydrocarbon product^*	37.04

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

Example 6 preparation of methanol reaction catalyst and evaluation of reaction (reaction scheme shown in FIG. 1)

The method is used for preparing the catalyst of the fixed bed for preparing the paraxylene and the gasoline by methanol on line in a micro fixed bed reaction device. The conditions for the on-line preparation of the catalyst were as follows: the FXCuZSM-5 catalyst prepared in the example 2 is tabletted, molded, crushed and sieved into 40-60 meshes, 5g (40-60 meshes) of the catalyst is loaded into a fixed bed reactor, treated by 50ml/min of nitrogen at 550 ℃ for 1 hour, and then cooled to 200 ℃ in a nitrogen atmosphere. Feeding a mixed solution of tetraethyl silicate and methanol by using a trace feed pump, wherein the weight ratio of tetraethyl silicate to methanol is 20:80, and the total weight space velocity of the tetraethyl silicate and the methanol is 1h^-1And normal pressure. Stopping feeding after 90min, blowing by using nitrogen, heating to 550 ℃, and roasting for 4 hours in an air atmosphere to prepare the fixed bed catalyst for co-production of p-xylene and gasoline by using methanol, which is named as FXMTGCAT-1.

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. C in the product of the methanol conversion reaction according to comparative example 1₄Olefin, benzene and toluene are prepared into raw materials and are fed by a trace feed pump (which is equivalent to separating C from a methanol conversion reaction product)₄Olefins, benzene, and toluene, and pumped back into the fixed bed reactor with a trace feed pump). The reaction product was analyzed by on-line Agilent7890 gas chromatography, and samples were taken for analysis at 60min of reaction. Deduction C₄The results of the reaction of the olefin with benzene and toluene are shown in table 2.

TABLE 2

Catalyst and process for preparing same	FXMTGCAT-1
		Reaction temperature (. degree.C.)	380
Methanol conversion (%)	100
		Selectivity (wt%) of p-xylene in xylene product	99.51
Product distribution (wt%)
		CH₄	3.82
C₂H₄	4.05
		C₂H₆	2.34
C₃H₆	3.55
		C₃H₈	12.53
C₄Alkane(s)	7.48
		C₅	7.00
C₆₊Chain hydrocarbons	3.10
		Ethylbenzene production	2.99
Para-xylene	48.94
		Meta-xylene	0.16
Ortho-xylene	0.08
		C₉Aromatic hydrocarbons	3.57
C₁₀₊Aromatic hydrocarbons	0.40

Gasoline component selectivity (wt%) in hydrocarbon product^*	17.30

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

Comparative example 2 methanol reaction catalyst preparation and reaction evaluation (no benzene, toluene and C)₄Olefin is returned to the reaction system for further reaction)

The method is used for preparing the catalyst of the fixed bed for preparing the paraxylene and the gasoline by methanol on line in a micro fixed bed reaction device. The conditions for the on-line preparation of the catalyst were as follows: the FXZnZSM-5 catalyst prepared in the example 3 is tableted, molded, crushed and sieved into 40-60 meshes, 5g (40-60 meshes) of the catalyst is loaded into a fixed bed reactor, treated by 50ml/min of nitrogen at 550 ℃ for 1 hour, and then cooled to 200 ℃ in a nitrogen atmosphere. Feeding a mixed solution of tetraethyl silicate and methanol by using a trace feed pump, wherein the weight ratio of tetraethyl silicate to methanol is 40:60, and the total weight space velocity of the tetraethyl silicate and the methanol is 1h^-1And normal pressure. And stopping feeding after 45min, blowing by using nitrogen, heating to 550 ℃, and roasting for 4 hours in an air atmosphere to prepare the fixed bed catalyst for co-production of p-xylene and gasoline from methanol, wherein the fixed bed catalyst is named as FXMTGCAT-2.

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the methanol preparation of the p-xylene is carried outThe toluene coproduction gasoline reaction has the following reaction conditions: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. The reaction product was analyzed by on-line Agilent7890 gas chromatography, and samples were taken for analysis at 60min of reaction. The reaction results are shown in Table 3.

TABLE 3

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

Example 7 preparation of methanol reaction catalyst and evaluation of reaction (reaction scheme shown in FIG. 1)

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. C in the product of the methanol conversion reaction according to comparative example 2₄Olefin, benzene and toluene are prepared into raw materials and are fed by a trace feed pump (equivalent to the method for preparing the olefin, the benzene and the tolueneSeparating C from methanol conversion reaction product₄Olefins, benzene, and toluene, and pumped back into the fixed bed reactor with a trace feed pump). The reaction product was analyzed by on-line Agilent7890 gas chromatography, and samples were taken for analysis at 60min of reaction. Deduction C₄The results of the reaction of the olefin with benzene and toluene are shown in Table 4.

TABLE 4

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

Comparative example 3 methanol reaction catalyst preparation and reaction evaluation (no benzene, toluene and C)₄Olefin is returned to the reaction system for further reaction)

The method is used for preparing the catalyst of the fixed bed for preparing the paraxylene and the gasoline by methanol on line in a micro fixed bed reaction device. The conditions for the on-line preparation of the catalyst were as follows: the FXGaZSM-5 catalyst prepared in example 4 is tableted, molded, crushed and sieved to 40-60 meshes, 5g (40-60 meshes) of the catalyst is loaded into a fixed bed reactor, treated by 50ml/min of nitrogen at 550 ℃ for 1 hour, and then cooled to 200 ℃ in a nitrogen atmosphere. Feeding a mixed solution of tetraethyl silicate and methanol by using a trace feed pump, wherein the weight ratio of tetraethyl silicate to methanol is 10:90, and the total weight space velocity of the tetraethyl silicate and the methanol is 1h^-1And normal pressure. Stopping feeding after 225min, purging with nitrogen, heating to 550 ℃, and roasting for 4 hours in an air atmosphere to obtain the fixed bed catalyst for co-production of p-xylene and gasoline from methanol, which is named as FXMTGCAT-3.

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. The reaction product is analyzed by on-line Agilent7890 gas chromatography, and the reaction is carried outSampling at 60min for analysis. The reaction results are shown in Table 5.

TABLE 5

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

Example 8 preparation of methanol reaction catalyst and evaluation of reaction (reaction scheme shown in FIG. 1)

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. C in the product of the methanol conversion reaction according to comparative example 3₄Olefin, benzene and toluene are prepared into raw materials and are fed by a trace feed pump (which is equivalent to separating C from a methanol conversion reaction product)₄Olefins, benzene, and toluene, and pumped back into the fixed bed reactor with a trace feed pump). The reaction product is analyzed by an on-line Agilent7890 gas chromatography, and the sample is taken and divided when the reaction is carried out for 60minAnd (6) analyzing. Deduction C₄The results of the reaction of the olefin with benzene and toluene are shown in Table 6.

TABLE 6

Catalyst and process for preparing same	FXMTGCAT-3
		Reaction temperature (. degree.C.)	380
Methanol conversion (%)	100
		Selectivity (wt%) of p-xylene in xylene product	99.77
Product distribution (wt%)
		CH₄	4.14
C₂H₄	2.73
		C₂H₆	2.47
C₃H₆	2.24
		C₃H₈	10.71
C₄Alkane(s)	7.10
		C₅	4.46
C₆₊Chain hydrocarbons	2.90
		Ethylbenzene production	2.08
Para-xylene	57.88
		Meta-xylene	0.07
Ortho-xylene	0.06
		C₉Aromatic hydrocarbons	2.78
C₁₀₊Aromatic hydrocarbons	0.36

Gasoline component selectivity (wt%) in hydrocarbon product^*	12.72

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

Comparative example 4 methanol reaction catalyst preparation and reaction evaluation (no benzene, toluene and C)₄Olefin is returned to the reaction system for further reaction)

The method is used for preparing the catalyst of the fixed bed for preparing the paraxylene and the gasoline by methanol on line in a micro fixed bed reaction device. The conditions for the on-line preparation of the catalyst were as follows: the FXLaZSM-5 catalyst prepared in example 5 is tableted, molded, crushed and sieved to 40-60 meshes, 5g (40-60 meshes) of the catalyst is loaded into a fixed bed reactor, treated by 50ml/min of nitrogen at 550 ℃ for 1 hour, and then cooled to 200 ℃ in a nitrogen atmosphere. Feeding a mixed solution of tetraethyl silicate and methanol by using a trace feed pump, wherein the weight ratio of tetraethyl silicate to methanol is 20:80, and the total weight space velocity of the tetraethyl silicate and the methanol is 1h^-1And normal pressure. Stopping feeding after 90min, blowing by using nitrogen, heating to 550 ℃, and roasting for 4 hours in an air atmosphere to prepare the fixed bed catalyst for co-production of p-xylene and gasoline by using methanol, which is named as FXMTGCAT-4.

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. The reaction product was analyzed by on-line Agilent7890 gas chromatography, and samples were taken for analysis at 60min of reaction. The reaction results are shown in Table 7.

TABLE 7

Catalyst and process for preparing same	FXMTGCAT-4
		Reaction temperature (. degree.C.)	380
Methanol conversion (%)	100
		Selectivity (wt%) of p-xylene in xylene product	99.69
Product distribution (wt%)
		CH₄	3.21
C₂H₄	3.86
		C₂H₆	1.78
C₃H₆	3.52
		C₃H₈	8.32
C₄Olefins	6.51
		C₄Alkane(s)	7.83
C₅	9.62
		C₆₊Chain hydrocarbons	6.38
Benzene and its derivatives	1.39
		Toluene	21.00
Ethylbenzene production	1.59
		Para-xylene	23.03
Meta-xylene	0.06
		Ortho-xylene	0.02
C₉Aromatic hydrocarbons	1.71
		C₁₀₊Aromatic hydrocarbons	0.15

		Gasoline component selectivity (wt%) in hydrocarbon product^*	41.92

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

Example 9 preparation of methanol reaction catalyst and evaluation of reaction (reaction scheme shown in FIG. 1)

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. C in the product of the methanol conversion reaction according to comparative example 4₄Olefin, benzene and toluene are prepared into raw materials and are fed by a trace feed pump (which is equivalent to separating C from a methanol conversion reaction product)₄Olefins, benzene, and toluene, and pumped back into the fixed bed reactor with a trace feed pump). The reaction product was analyzed by on-line Agilent7890 gas chromatography, and samples were taken for analysis at 60min of reaction. Deduction C₄The results of the reaction of the olefin with benzene and toluene are shown in Table 8.

TABLE 8

Catalyst and process for preparing same	FXMTGCAT-4
		Reaction temperature (. degree.C.)	380
Methanol conversion (%)	100
		Selectivity (wt%) of p-xylene in xylene product	99.65
Product distribution (wt%)
		CH₄	3.27
C₂H₄	3.93
		C₂H₆	1.82
C₃H₆	3.58
		C₃H₈	8.47
C₄Alkane(s)	8.32
		C₅	9.80
C₆₊Chain hydrocarbons	6.50
		Ethylbenzene production	3.24
Para-xylene	47.09
		Meta-xylene	0.13
Ortho-xylene	0.04
		C₉Aromatic hydrocarbons	3.50
C₁₀₊Aromatic hydrocarbons	0.31

Gasoline component selectivity (wt%) in hydrocarbon product^*	23.52

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

Comparative example 5 methanol reaction catalyst preparation and reaction evaluation (no benzene, toluene and C)₄Olefin is returned to the reaction system for further reaction)

The method is used for preparing the catalyst of the fixed bed for preparing the paraxylene and the gasoline by methanol on line in a micro fixed bed reaction device. On-line preparation of catalystsThe conditions of the reagent were as follows: the FXGaZSM-5 catalyst prepared in example 4 is tableted, molded, crushed and sieved to 40-60 meshes, 5g (40-60 meshes) of the catalyst is loaded into a fixed bed reactor, treated by 50ml/min of nitrogen at 550 ℃ for 1 hour, and then cooled to 450 ℃ in a nitrogen atmosphere. Feeding a mixed solution of tetraethyl silicate and methanol by using a trace feed pump, wherein the weight ratio of tetraethyl silicate to methanol is 20:80, and the total weight space velocity of the tetraethyl silicate and the methanol is 1h^-1And normal pressure. Stopping feeding after 90min, blowing by using nitrogen, heating to 550 ℃, and roasting for 4 hours in an air atmosphere to prepare the fixed bed catalyst for co-production of p-xylene and gasoline from methanol, which is named as FXMTGCAT-5.

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. The reaction product was analyzed by on-line Agilent7890 gas chromatography, and samples were taken for analysis at 60min of reaction. The reaction results are shown in Table 9.

TABLE 9

Catalyst and process for preparing same	FXMTGCAT-5
		Reaction temperature (. degree.C.)	380
Methanol conversion (%)	100
		Selectivity (wt%) of p-xylene in xylene product	99.66
Product distribution (wt)％)
		CH₄	3.23
C₂H₄	2.81
		C₂H₆	2.58
C₃H₆	2.19
		C₃H₈	12.06
C₄Olefins	5.33
		C₄Alkane(s)	6.76
C₅	5.12
		C₆₊Chain hydrocarbons	3.44
Benzene and its derivatives	2.30
		Toluene	23.66
Ethylbenzene production	1.19
		Para-xylene	27.68
Meta-xylene	0.06
		Ortho-xylene	0.03
C₉Aromatic hydrocarbons	1.45
		C₁₀₊Aromatic hydrocarbons	0.11

		Gasoline component selectivity (wt%) in hydrocarbon product^*	37.36

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

Example 10 preparation of methanol reaction catalyst and evaluation of reaction (reaction scheme shown in FIG. 1)

The method is used for preparing the catalyst of the fixed bed for preparing the paraxylene and the gasoline by methanol on line in a micro fixed bed reaction device. The conditions for the on-line preparation of the catalyst were as follows: tabletting and molding the FXGaZSM-5 catalyst prepared in the example 4, crushing and screening the obtained product into 40-60 meshes, putting 5g (40-60 meshes) of the catalyst into a fixed bed reactor, and firstly introducing 50ml/min nitrogen into the fixed bed reactor at 550The treatment was carried out for 1 hour, and then the temperature was lowered to 450 ℃ under a nitrogen atmosphere. Feeding a mixed solution of tetraethyl silicate and methanol by using a trace feed pump, wherein the weight ratio of tetraethyl silicate to methanol is 20:80, and the total weight space velocity of the tetraethyl silicate and the methanol is 1h^-1And normal pressure. Stopping feeding after 90min, blowing by using nitrogen, heating to 550 ℃, and roasting for 4 hours in an air atmosphere to prepare the fixed bed catalyst for co-production of p-xylene and gasoline from methanol, which is named as FXMTGCAT-5.

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. C in the product of the methanol conversion reaction according to comparative example 5₄Olefin, benzene and toluene are prepared into raw materials and are fed by a trace feed pump (which is equivalent to separating C from a methanol conversion reaction product)₄Olefins, benzene, and toluene, and pumped back into the fixed bed reactor with a trace feed pump). The reaction product was analyzed by on-line Agilent7890 gas chromatography, and samples were taken for analysis at 60min of reaction. Deduction C₄The results of the reaction of the olefin with benzene and toluene are shown in Table 10.

Watch 10

Catalyst and process for preparing same	FXMTGCAT-5
		Reaction temperature (. degree.C.)	380
Methanol conversion (%)	100
		Selectivity (wt%) of p-xylene in xylene product	99.68
Product distribution (wt%)
		CH₄	3.27
C₂H₄	2.85
		C₂H₆	2.62
C₃H₆	2.22
		C₃H₈	12.22
C₄Alkane(s)	7.11
		C₅	5.18
C₆₊Chain hydrocarbons	3.49
		Ethylbenzene production	2.41
Para-xylene	55.33
		Meta-xylene	0.12
Ortho-xylene	0.06
		C₉Aromatic hydrocarbons	2.90
C₁₀₊Aromatic hydrocarbons	0.22

Gasoline component selectivity (wt%) in hydrocarbon product^*	14.38

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

Comparative example 6 methanol reaction catalyst preparation and reaction evaluation (no benzene, toluene and C)₄Olefin is returned to the reaction system for further reaction)

The method is used for preparing the catalyst of the fixed bed for preparing the paraxylene and the gasoline by methanol on line in a micro fixed bed reaction device. The conditions for the on-line preparation of the catalyst were as follows: the FXGaZSM-5 catalyst prepared in example 4 is tableted, molded, crushed and sieved to 40-60 meshes, 5g (40-60 meshes) of the catalyst is loaded into a fixed bed reactor, treated by 50ml/min of nitrogen at 550 ℃ for 1 hour, and then cooled to 150 ℃ in a nitrogen atmosphere. Feeding a mixed solution of tetramethyl silicate and methanol by using a trace feed pump, wherein the weight ratio of the tetramethyl silicate to the methanol is 20:80, and the total weight space velocity of the tetramethyl silicate and the methanol is 1h^-1And normal pressure. Stopping feeding after 90min, purging with nitrogen, and heating to 550 deg.CRoasting for 4 hours at the air atmosphere to prepare the fixed bed catalyst for co-production of p-xylene and gasoline by methanol, which is named as FXMTGCAT-6.

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: the raw material is fed by a trace feed pump, and the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. The reaction product was analyzed by on-line Agilent7890 gas chromatography, and samples were taken for analysis at 60min of reaction. The reaction results are shown in Table 11.

TABLE 11

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

EXAMPLE 11 preparation of methanol reaction catalyst and evaluation of reaction (reaction scheme shown in FIG. 1)

The method is used for preparing the catalyst of the fixed bed for preparing the paraxylene and the gasoline by methanol on line in a micro fixed bed reaction device. The conditions for the on-line preparation of the catalyst were as follows: the FXGaZSM-5 catalyst prepared in example 4 is tableted, molded, crushed and sieved to 40-60 meshes, 5g (40-60 meshes) of the catalyst is loaded into a fixed bed reactor, treated by 50ml/min of nitrogen at 550 ℃ for 1 hour, and then cooled to 150 ℃ in a nitrogen atmosphere. Feeding a mixed solution of tetramethyl silicate and methanol by using a trace feed pump, wherein the weight ratio of the tetramethyl silicate to the methanol is 20:80, and the total weight space velocity of the tetramethyl silicate and the methanol is 1h^-1And normal pressure. Stopping feeding after 90min, blowing by using nitrogen, heating to 550 ℃, and roasting for 4 hours in an air atmosphere to prepare the fixed bed catalyst for co-production of p-xylene and gasoline by using methanol, which is named as FXMTGCAT-6.

Then, the temperature is reduced to 380 ℃ in the nitrogen atmosphere, and the reaction of preparing paraxylene and gasoline by methanol is carried out, wherein the reaction conditions are as follows: raw materialsFeeding with a trace feed pump, wherein the total weight space velocity of the methanol is 2h^-1The reaction pressure was 0.5 MPa. C in the product of the methanol conversion reaction according to comparative example 6₄Olefin, benzene and toluene are prepared into raw materials and are fed by a trace feed pump (which is equivalent to separating C from a methanol conversion reaction product)₄Olefins, benzene, and toluene, and pumped back into the fixed bed reactor with a trace feed pump). The reaction product was analyzed by on-line Agilent7890 gas chromatography, and samples were taken for analysis at 60min of reaction. Deduction C₄The results of the reaction of the olefin with benzene and toluene are shown in Table 12.

TABLE 12

^*Comprising C₅、C₆₊Chain and aromatic hydrocarbons (excluding p-xylene)

EXAMPLE 12 preparation of methanol reaction catalyst and evaluation of reaction (reaction scheme shown in FIG. 1)

The methanol-to-p-xylene co-production gasoline reaction was performed in the same procedure as described in example 6 using the methanol reaction catalyst FXMTGCAT-1 prepared in example 6. The differences are as follows: argon atmosphere, reaction temperature of 350 ℃, and space velocity of total weight of methanol of 3h^-1The reaction pressure was 0.3 MPa. The reaction results are similar to those in Table 2.

Example 13 preparation of methanol reaction catalyst and evaluation of reaction (reaction scheme shown in FIG. 1)

The methanol-to-p-xylene co-production gasoline reaction was performed in the same procedure as described in example 6 using the methanol reaction catalyst FXMTGCAT-1 prepared in example 6. The differences are as follows: helium atmosphere, the reaction temperature is 410 ℃, and the space velocity of the total weight of the methanol is 1h^-1The reaction pressure was 0.7 MPa. The reaction results are similar to those in Table 2.

As can be seen from the above experimental results, the weight percentage of p-xylene in the product distribution was not less than 47.09 wt%. Further, in the product distribution, the weight percentage of the paraxylene is 47.09-59.29 wt%, and the weight percentage of the gasoline component is 10.26-23.52 wt%.

Although the present application has been described with reference to a few embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the application as defined by the appended claims.

Claims

1. a method for preparing p-xylene co-production gasoline by methanol and/or dimethyl ether, is characterized in that, at least comprises the following steps:

a) contacting and reacting a raw material containing methanol and/or dimethyl ether with a catalyst to obtain a mixture; and separating the components containing benzene and toluene, the components containing C ₄ olefins, the components containing p-xylene and gasoline from the obtained mixture divided product;

b) Returning the benzene and toluene-containing components and the _C4 olefin-containing components to step a) for co-feed reaction with methanol and/or dimethyl ether-containing feedstocks.

2 . The method according to claim 1 , wherein the reaction conditions include: an inert gas atmosphere, a reaction temperature of 350 to 410° C., a reaction pressure of 0.3 to 0.7 MPa, and the weight of methanol and/or dimethyl ether. 3 . Airspeed 1～3h ^-1 .

3. The method according to claim 1, wherein the catalyst is selected from at least one of zeolite molecular sieve catalysts modified by metals and silylating agents.

4 . The method according to claim 3 , wherein the catalyst is obtained from HZSM-5 zeolite molecular sieve through metal modification and silanization reagent modification. 5 .

5. The method according to claim 3, wherein the metal in the metal modification is selected from one or two of copper, zinc, gallium and lanthanum.

6. The method according to claim 3, wherein the silylating agent is selected from at least one of compounds having the following chemical formula:

wherein R ₁ , R ₂ , R ₃ and R ₄ are each independently selected from C _1-10 alkyl, C _1-10 alkoxy.

7. The method according to claim 6, wherein at least one of R ₁ , R ₂ , R ₃ and R ₄ is selected from C _1-10 alkoxy groups.

8. The method according to claim 7, wherein the silylating agent is selected from at least one of tetraethyl silicate and tetramethyl silicate.

9. The method according to any one of claims 1 to 8, wherein at least the following steps are included:

1) make the raw material containing methanol and/or dimethyl ether contact and react with the catalyst in the reaction system to obtain a mixture;

2) The mixture enters the first separation system, and separates to obtain the C ₄ olefin-containing component and the C ₅₊ component; the C ₄ olefin-containing component is returned to the reaction system;

3) The C ₅₊ component enters the second separation system, and separates to obtain a component containing benzene and toluene, a product containing p-xylene and a gasoline component; the component containing benzene and toluene is returned to the reaction system .

10. The method according to claim 9, wherein the reaction system comprises one reactor or a plurality of reactors connected in series and/or parallel;

Preferably, the reactor is selected from at least one of fixed bed, fluidized bed and moving bed.