CN106588528B - Moving bed method for preparing p-xylene and co-producing low-carbon olefin by using methanol and/or dimethyl ether - Google Patents

Abstract

The invention provides a moving bed method for preparing para-xylene and co-producing low-carbon olefins by converting methanol and/or dimethyl ether. Batch feeding into multiple reactors in series effectively improves the yield of paraxylene, and the catalyst maintains high reactivity and stability through continuous movement reaction-regeneration of the catalyst.

Description

Moving bed method for co-production of light olefins with methanol and/or dimethyl ether for the preparation of para-xylene

technical field

The invention belongs to the field of chemistry and chemical industry, and more particularly relates to a moving bed process for preparing para-xylene and co-producing low-carbon olefins (ie C ₂ -C ₃ olefins) from methanol and/or dimethyl ether.

Background technique

Both paraxylene (PX) and light olefins are important basic chemical raw materials. At present, para-xylene is mainly obtained through aromatics complexes. Since the content of p-xylene in the three isomers of xylene is controlled by thermodynamics, p-xylene accounts for only about 23%, especially the boiling point difference between p-xylene and m-xylene is very small, and the usual distillation technology cannot be used. To obtain high-purity p-xylene, an adsorption separation process with high investment and operating costs must be adopted, so the material recycling processing capacity in the entire PX production process is large, the equipment is large, and the operating cost is high. Low-carbon olefins are mainly obtained from by-products of petroleum refineries and steam cracking of naphtha. In addition, since the successful operation of the Shenhua Baotou 1.8 million-ton methanol to low-carbon olefin (DMTO) industrial plant using the patented technology of Dalian Chemical Institute in 2009, it has opened up a new way to produce low-carbon olefins from coal through methanol. Para-xylene is mainly used to produce polyester, and low-carbon olefin is mainly used to prepare polyolefin and ethylene glycol, 1,3-propanediol, etc. required for polyester production. With the rapid development of the global economy, the demand for paraxylene and light olefins as basic chemical raw materials is also increasing year by year.

In recent years, many patents at home and abroad have disclosed new ways to produce p-xylene, among which toluene methylation can produce p-xylene with high selectivity.美国专利USP 3,965,207、USP 3,965,208、USP 4,250,345、USP 4,670,616、USP 4,276,438、USP 4,278,827、USP 4,444,989、USP 4,491,678、USP 5,034,362、USP 5,563，310、USP 6,504,072和USP 6,613,708等均公开了在改性催化剂上甲苯烷Method for the preparation of p-dialkylbenzenes by radicalization. Chinese patents ZL200610011662.4, ZL200710176269.5, ZL200710176274.6, ZL 200710179408.X, ZL 200710179409.4 and ZL 200710179410.7 disclose a kind of method for the co-production of light olefins from toluene methanol to p-xylene methanol on a catalyst. It can co-produce high-selectivity ethylene and propylene while converting to produce high-selectivity p-xylene. However, the production of p-xylene and light olefins by alkylation of toluene with methanol still relies on petroleum resources, thus restricting its industrial application. While Chinese patent applications CN 101244969, CN 1880288 and U.S. Patent US 4615995 disclose the technology of converting methanol to prepare aromatics or olefins, the economical value of the aromatics products is relatively low, so the economy is poor.

Chinese patent applications CN101767038 B and CN 101780417 B disclose a catalyst and method for converting methanol and/or dimethyl ether to prepare p-xylene and light olefins, and point out that a reaction process is achieved on metals and silylation modified catalysts The purpose of directly producing three basic chemicals ethylene, propylene and p-xylene from methanol. In the hydrocarbon product obtained by the reaction, the selectivity of paraxylene in aromatic hydrocarbons is more than 80 wt%, and the selectivity of ethylene and propylene in low-carbon hydrocarbons is more than 80 wt%. However, the drawbacks of this method are short catalyst life and poor stability, which limit the industrial application of this technology.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a kind of methanol and/or dimethyl ether to prepare para-xylene co-production low-carbon moving bed process method, by feeding raw material methanol and/or dimethyl ether into the reactor in batches to react with the previous stage The aromatic products such as benzene and toluene generated in the reactor product are further subjected to alkylation reaction, so that the yield of p-xylene in the product can be effectively improved through the continuous reaction of the multi-stage reactors connected in series.

Another object of the present invention is to use the moving bed process in which the catalyst moves continuously, so that the catalyst can be continuously reacted and regenerated, and the activity and stability of the catalyst can be improved.

To this end, the present invention provides a moving bed method for preparing para-xylene and co-producing light olefins from methanol and/or dimethyl ether. step:

Passing the first batch of raw material methanol and/or dimethyl ether into the first reactor and contacting and reacting with the catalyst in the first reactor;

The first reaction product flowing out from the first reactor is mixed with the second batch of raw materials methanol and/or dimethyl ether, and then passed into the second reactor and contacted and reacted with the catalyst in the second reactor;

The second reaction product flowing out from the second reactor is mixed with the third batch of raw materials methanol and/or dimethyl ether, then passed into the third reactor and contacted and reacted with the catalyst in the third reactor;

The third reaction product flowing out from the third reactor is separated to obtain p-xylene and light olefin products;

Wherein, the catalyst continuously flowing out from the first reactor enters the second reactor through gas lifting and is used as the catalyst in the second reactor, and the catalyst continuously flowing out from the second reactor enters the third reactor through gas lifting and is used as the third reactor For the catalyst in the reactor, the catalyst continuously flowing out from the third reactor enters the catalyst regenerator through gas lifting and undergoes coke regeneration, and the regenerated catalyst continuously flowing out from the catalyst regenerator enters the first reactor through gas lifting, thereby making The catalyst is continuously moved between the first reactor, the second reactor, the third reactor and the catalyst regenerator for reaction-regeneration cycle.

In a preferred embodiment, the catalyst is a modified HZSM-5 and/or HZSM-11 zeolite molecular sieve catalyst with MFI topology.

In a preferred embodiment, the catalyst is a modified HZSM-5 zeolite molecular sieve catalyst prepared by the following steps:

The ZSM-5 zeolite molecular sieve is subjected to NH ₄ ⁺ ion exchange, and centrifuged, and the solid product is dried in an air atmosphere of 100-150 °C and calcined in an air atmosphere of 500-600 °C to obtain an acidic HZSM-5 zeolite molecular sieve;

The obtained acidic HZSM-5 zeolite molecular sieve is continuously immersed in the soluble salt solution of zinc and gallium, and then centrifuged, and the solid product is dried in an air atmosphere of 100-150 ° C and calcined in an air atmosphere of 500-600 ° C to obtain the metal Modified HZSM-5 zeolite molecular sieve;

The obtained metal-modified HZSM-5 zeolite molecular sieve is immersed in a siloxane-based reagent, and then centrifuged, and the solid product is dried in an air atmosphere of 100-150 ° C and calcined in an air atmosphere of 500-600 ° C to obtain the metal and a silicon-modified HZSM-5 zeolite molecular sieve catalyst; and

The obtained metal and silicon modified HZSM-5 zeolite molecular sieve is subjected to hydrothermal treatment in a water vapor atmosphere of 500-600 ° C for 2-12 hours to obtain the desired modified HZSM-5 zeolite molecular sieve catalyst,

wherein the siloxane-based compound has the formula:

wherein R ₁ , R ₂ , R ₃ and R ₄ independently represent a C _1-10 alkyl group.

In a preferred embodiment, in the metal-modified HZSM-5 zeolite molecular sieve, the total content of zinc and gallium is 0.1-8 wt % of the total weight of the catalyst.

In a preferred embodiment, the loading amount of silicon in the modified HZSM-5 zeolite molecular sieve catalyst is 1-10 wt % of the total weight of the catalyst.

In a preferred embodiment, the siloxane-based compound is ethyl orthosilicate.

In a preferred embodiment, the reaction temperature in the first reactor, the second reactor and the third reactor is 300-600°C, preferably 450-550°C.

In a preferred embodiment, based on the catalyst mass in the first reactor, the feed mass space velocity of the first batch of raw materials methanol and/or dimethyl ether is 0.1-10 h ^-1 , preferably 1-5 h ^-1 .

In a preferred embodiment, the molar ratio of the feed amount of the second batch and the third batch of raw materials methanol and/or dimethyl ether to the feed amount of the first batch of raw material methanol and/or dimethyl ether They are respectively 0.1 to 1:1, preferably 0.1 to 0.5:1.

In a preferred embodiment, the moving bed of the plurality of reactors in series comprises three or more reactors in series, preferably three reactors in series.

The beneficial effects of the present invention include, but are not limited to: passing the first batch of raw materials methanol and/or dimethyl ether into the first reactor, contacting with the catalyst in the first reactor to carry out cracking and shape-selective aromatization reaction, to generate low-carbon olefins and The first product of aromatic hydrocarbons such as benzene, toluene and p-xylene; the first product is mixed with the second batch of raw materials methanol and/or dimethyl ether and then enters the second reactor, and is contacted with the catalyst in it for cracking, shape-selective aromatization and alkylation reaction to further generate the second product containing light olefins and aromatic hydrocarbons such as benzene, toluene and p-xylene; the second product is mixed with the third batch of raw materials methanol and/or dimethyl ether and then enters the third reaction The reactor is contacted with the catalyst inside to carry out cracking, shape-selective aromatization and alkylation reactions, and further generates a third product containing aromatic hydrocarbons such as low-carbon olefins and p-xylene; the third product is separated to obtain p-xylene and low-carbon The carbene product, optionally by-product toluene, can be passed back into the first reactor for re-reaction in admixture with the first batch of feedstock methanol and/or dimethyl ether. The invention effectively improves the yield of p-xylene in the product through the continuous reaction of multi-stage reactors in series, and at the same time, by adopting the moving bed process in which the catalyst moves continuously, the catalyst can be continuously reacted and regenerated, and the activity and stability of the catalyst are improved. sex.

Description of drawings

Figure 1 is a flow diagram of a moving bed process according to a preferred embodiment of the present invention.

Detailed ways

The moving bed method of the present invention for preparing para-xylene and co-producing light olefins from methanol and/or dimethyl ether is further described below with reference to FIG. 1 . As shown in Figure 1, the method includes the following steps:

The first batch of raw materials (that is, methanol and/or dimethyl ether 01 in Figure 1) are passed into the first reactor R101 to contact and react with the catalyst;

The first product flowing out from the first reactor R101 (ie product (1) in Figure 1 ) is mixed with the second batch of raw materials (ie methanol and/or dimethyl ether 02 in Figure 1 ) and then passed into the second reactor R102 reacts with the catalyst;

The second product flowing out from the second reactor R102 (ie, product (2) in Figure 1 ) is mixed with the third batch of raw materials (ie, methanol and/or dimethyl ether 03 in Figure 1 ) and then passed into the third reaction The device R103 contacts and reacts with the catalyst;

The third product flowing out from the third reactor R103 (ie, product (3) in Figure 1) is separated to obtain para-xylene and light olefin products; optionally, by-product toluene is returned and combined with the first batch of feedstock methanol and /or dimethyl ether 01 is mixed and passed into the first reactor R101 to continue contacting and reacting with the catalyst,

Wherein, the catalyst continuously flowing out of the reactor R101 is lifted by gas (that is, the lift gas in FIG. 1 , for example, it can be N ₂ , H ₂ or a mixed non-condensable gas of H ₂ , CH ₄ , CO and CO ₂ obtained from N 2 , H 2 or separated from the product) Enter the reactor R102, the catalyst continuously flowing out from the reactor R102 enters the reactor R103 through gas lifting, and the catalyst continuously flowing out from the reactor R103 enters the regenerator R201 through the gas lifting for coke regeneration (using regeneration gas such as N ₂ +O ₂ mixed gas), the regenerated catalyst continuously flowing out from the regenerator R201 is lifted into the reactor R101 by gas; the catalyst is continuously moved in the reactors R101, R102, R103 and the regenerator R201 for reaction-regeneration cycle.

Preferably, in the moving bed method for preparing para-xylene and co-producing light olefins from methanol and/or dimethyl ether, more than two reactors are used in series moving beds, preferably three reactors are connected in series moving beds.

Preferably, the catalyst adopts a modified HZSM-5 and/or HZSM-11 zeolite molecular sieve catalyst with MFI topology and with shape-selective properties, preferably a modified HZSM-5 zeolite molecular sieve catalyst.

Preferably, the preparation process of the modified HZSM-5 zeolite molecular sieve catalyst is as follows:

(1) ZSM-5 zeolite molecular sieve is subjected to NH ₄ ⁺ ion exchange for many times, for example, 4 times, and then centrifuged, the solid is dried in an air atmosphere at 100-150°C, such as 120°C, and calcined in an air atmosphere at 500-600°C to obtain acidity HZSM-5 zeolite molecular sieve.

(2) The acidic HZSM-5 zeolite molecular sieve obtained in step (1) is continuously immersed in the soluble salt of zinc and gallium, and after centrifugal separation, the solid is dried in an air atmosphere at 100-150°C, such as 120°C, and dried at 500-600°C. calcination in air atmosphere to obtain metal modified HZSM-5 zeolite molecular sieve;

(3) The metal-modified HZSM-5 zeolite obtained in step (2) is immersed in a siloxane-based reagent, centrifuged, and the solid is dried in an air atmosphere at 100-150°C, such as 120°C, and dried in an air atmosphere at 500-600°C. calcination in atmosphere to obtain metal and silicon modified HZSM-5 zeolite molecular sieve catalyst.

(4) The metal and silicon modified HZSM-5 zeolite molecular sieve in step (3) is subjected to hydrothermal treatment in a steam atmosphere of 500-600° C. for 2-12 hours to obtain the desired modified HZSM-5 zeolite molecular sieve catalyst.

Preferably, after the catalyst is modified by zinc and gallium bimetals, the total bimetal content is 0.1-8 wt% of the total weight of the catalyst.

Preferably, after the catalyst is modified with a siloxane-based compound, the loading amount of Si is 1-10 wt % of the total weight of the catalyst.

Preferably, the siloxane-based compound used is represented by the formula:

wherein R ₁ , R ₂ , R ₃ and R ₄ independently represent a C _1-10 alkyl group.

Preferably, the siloxane-based compound used is tetraethylorthosilicate.

Preferably, the reaction temperature of methanol and/or dimethyl ether in the multistage moving bed reactor is 300-600°C, preferably 450-550°C.

Preferably, based on the catalyst mass in the reactor R101, the feed mass space velocity of the raw material methanol and/or dimethyl ether 01 is 0.1-10 h ^-1 , preferably 1-5 h ^-1 ; the reactor R102 raw material methanol and/or dimethyl ether The feed amount of ether 02 and the feed amount of methanol and/or dimethyl ether 03 of the reactor R103 and the feed amount of methanol and/or dimethyl ether 01 of the reactor R101 are respectively 0.1～1:1, preferably 0.1～ 0.5:1.

The present invention will be described in detail below by means of examples, but the present invention is not limited to these examples.

Example 1 (Catalyst Preparation)

(1) 150kg ZSM-5 zeolite molecular sieve original powder (SiO ₂ /Al ₂ O ₃ =50) was calcined at 550°C to remove the template agent, and exchanged 4 times with 0.5 molar equivalent ammonium nitrate solution in a water bath at 80°C. Then, it is dried in an air atmosphere at 120° C., and calcined in an air atmosphere at a temperature of 550° C. for 3 hours to obtain the HZSM-5 zeolite molecular sieve.

(2) 120 kg of HZSM-5 zeolite molecular sieves obtained in step (1) were added to 150 kg of zinc nitrate aqueous solution with a concentration of 12% and immersed for about 6 hours, then the solid sample was centrifuged, dried in an air atmosphere of 120° C., and dried at 550° C. calcination in air atmosphere for 4 hours to obtain zinc-modified HZSM-5 zeolite molecular sieve.

(3) The zinc-modified HZSM-5 zeolite molecular sieve obtained in step (2) was added to 150 kg of gallium nitrate aqueous solution with a concentration of 15 wt % and immersed for about 6 hours, and then the solid sample was centrifuged, dried in an air atmosphere of 120 ° C, and dried at 550 °C. calcination in air atmosphere for 4 hours to obtain zinc gallium modified HZSM-5 zeolite molecular sieve.

(4) The zinc-gallium modified HZSM-5 zeolite molecular sieve obtained in step (3) was added to 120 kg of tetraethyl silicate and immersed for 12 hours, then the solid sample was centrifuged, dried at 120°C, and dried at 550°C in an air atmosphere After calcination for 4 hours, a zinc gallium and silicon modified HZSM-5 zeolite molecular sieve catalyst was obtained.

(5) hydrothermally heat 120 kg of the zinc-gallium and silicon-modified HZSM-5 zeolite molecular sieves obtained in step (4) in a 550° C. steam atmosphere for 6 hours to obtain a modified HZSM-5 zeolite molecular sieve catalyst. Elemental analysis Zinc loading was 2.31 wt % of the total catalyst mass, gallium loading was 3.28 wt % of the total catalyst mass, and Si loading was 5.63 wt % of the total catalyst mass.

(6) Mix the HZSM-5 zeolite molecular sieve catalyst 100kg (dry basis 95wt%) + silica sol 100kg (SiO ₂ content 40.7wt%) + an appropriate amount of deionized water obtained in step (5) and extrude it into 1.6mm spherical particles , to obtain a shaped HZSM-5 zeolite molecular sieve catalyst, named HPXC-01.

Example 2 (Reaction Evaluation)

Each 30kg of catalyst HPXC-01 prepared in Example 1 was loaded into reactors R101, R102 and R103 respectively, and 20kg was loaded into reactor R201 regenerator, so that the catalyst was moved into the gas lift pipeline and replenished in the regenerator. Add catalyst. The catalyst in the reactor was treated in a nitrogen atmosphere at 550°C for 1 hour, and then cooled to a reaction temperature of 520°C. The raw material methanol 01 is passed into the reactor R101, another part of the raw material methanol 02 is mixed with the product (1) of the reactor R101 and then passed into the reactor R102, and another part of the raw material methanol 03 is mixed with the product (2) of the reactor R102. After passing into the reactor R103, it is respectively contacted and reacted with the catalyst. In terms of the catalyst mass in the reactor R101, the methanol 01 feed mass space velocity is 3h ^-1 , and the mol ratio of the methanol 02 and methanol 03 in the reactors R102 and R103 to the methanol 01 in the reactor R101 is 0.3:1, The reaction product (3) is analyzed online by gas chromatography, and the composition of the non-aqueous product is shown in Table 1;

Example 3 (Reaction Evaluation)

The reaction conditions were the same as those in Example 2, except that the methanol raw material was replaced with dimethyl ether. The raw material dimethyl ether 01 is passed into the reactor R101, then another part of the raw material dimethyl ether 02 and the R101 product (1) are mixed and passed into the reactor R102, and another part of the raw material dimethyl ether 03 and the R102 product (2) After mixing, it is passed into the reactor R103 to contact and react with the catalyst respectively. In terms of catalyst mass in reactor R101, the feed mass space velocity of dimethyl ether 01 is 2h ^-1 , and the moles of feed dimethyl ether 02 in reactors R102 and R103, dimethyl ether 03 and dimethyl ether 01 in R101 The ratio is 0.5:1, the reaction product (3) is analyzed online by gas chromatography, and the composition of the non-aqueous product is shown in Table 1;

Example 4 (reaction evaluation)

The reaction conditions were the same as those in Example 2, except that the methanol raw material was replaced with a mixture of methanol and dimethyl ether. The mixture 01 of methanol and dimethyl ether with a molar ratio of 2:1 was passed into the reactor R101, and then another part of the mixture 02 of methanol and dimethyl ether with a molar ratio of 2:1 was mixed with the R101 product (1) and passed into the reactor. In the reactor R102, another part of the mixture 03 of methanol and dimethyl ether with a molar ratio of 2:1 is mixed with the R102 product (2), and then passed into the reactor R103 to contact and react with the catalyst respectively. The feed mass space velocity of methanol and dimethyl ether mixture 01 is 5h ^-1 based on the catalyst mass in reactor R101, and methanol and dimethyl ether mixture 02, methanol and dimethyl ether mixture 03 and R101 are fed in reactors R102 and R103 The mol ratio of the mixture 01 of feed methanol and dimethyl ether is 0.2: 1, and the reaction product (3) is analyzed online by gas chromatography, and the non-aqueous product composition is as shown in Table 1; Toluene in the separation aromatics is recycled to obtain a non-aqueous product. The product composition is shown in Table 2.

Table 1

^* wt% is mass content.

Table 2

^* wt% is mass content.

The above-mentioned embodiments are only to illustrate the technical concept and characteristics of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement them accordingly, and these embodiments do not limit the protection scope of the present invention in any way. Without departing from the spirit and scope of the present invention, any changes or modifications made should be included within the protection scope of the present invention.

Claims (12)

1. a moving bed method for preparing paraxylene co-production light olefins with methanol and/or dimethyl ether, is characterized in that, adopts the moving bed connected in series by a plurality of reactors, and the method comprises the following steps: Passing the first batch of raw material methanol and/or dimethyl ether into the first reactor and contacting and reacting with the catalyst in the first reactor; The first reaction product flowing out from the first reactor is mixed with the second batch of raw materials methanol and/or dimethyl ether, and then passed into the second reactor and contacted and reacted with the catalyst in the second reactor; The second reaction product flowing out from the second reactor is mixed with the third batch of raw materials methanol and/or dimethyl ether, then passed into the third reactor and contacted and reacted with the catalyst in the third reactor; The third reaction product flowing out from the third reactor is separated to obtain p-xylene and light olefin products; Wherein, the catalyst continuously flowing out from the first reactor enters the second reactor through gas lifting and is used as the catalyst in the second reactor, and the catalyst continuously flowing out from the second reactor enters the third reactor through gas lifting and is used as the third reactor For the catalyst in the reactor, the catalyst continuously flowing out from the third reactor enters the catalyst regenerator through gas lift and undergoes coke regeneration, and the regenerated catalyst flowing out from the catalyst regenerator enters the first reactor through gas lift, thereby making the catalyst Continuously move the reaction-regeneration cycle between the first reactor, the second reactor, the third reactor and the catalyst regenerator, And wherein, the catalyst is a modified HZSM-5 zeolite molecular sieve catalyst prepared by the following steps: After the ZSM-5 zeolite molecular sieve is exchanged with NH ₄ ⁺ ions, it is dried and calcined to obtain the acidic HZSM-5 zeolite molecular sieve; The obtained acidic HZSM-5 zeolite molecular sieve is continuously impregnated with soluble salts of zinc and gallium, dried and roasted to obtain the metal-modified HZSM-5 zeolite molecular sieve; Impregnating the obtained metal-modified HZSM-5 zeolite molecular sieve in a siloxane-based reagent for surface modification, drying and calcining to obtain a metal- and silicon-modified HZSM-5 zeolite molecular sieve catalyst; and The obtained metal and silicon modified HZSM-5 zeolite molecular sieve is subjected to hydrothermal treatment in a steam atmosphere to obtain the desired modified HZSM-5 zeolite molecular sieve catalyst, wherein the siloxane-based compound has the formula:

wherein R ₁ , R ₂ , R ₃ and R ₄ independently represent a C _1-10 alkyl group. 2 . The moving bed method according to claim 1 , wherein the catalyst is a modified HZSM-5 zeolite molecular sieve catalyst with MFI topology. 3 . 3 . The moving bed method according to claim 1 , wherein, in the metal-modified HZSM-5 zeolite molecular sieve, the total content of zinc and gallium is 0.1-8 wt % of the total weight of the catalyst. 4 . 4 . The moving bed method according to claim 1 , wherein the loading amount of silicon in the modified HZSM-5 zeolite molecular sieve catalyst is 1-10 wt % of the total weight of the catalyst. 5 . 5. The moving bed method according to claim 1, wherein the siloxane-based compound is ethyl orthosilicate. 6 . The moving bed method according to claim 1 , wherein the reaction temperature in the first reactor, the second reactor and the third reactor is 300-600° C. 7 . 7 . The moving bed method according to claim 1 , wherein the reaction temperature in the first reactor, the second reactor and the third reactor is 450-550° C. 8 . 8. moving bed method according to claim 1 is characterized in that, in terms of catalyst mass in the first reactor, the feed mass space velocity of the first batch of raw materials methanol and/or dimethyl ether is 0.1-10h ^{− 1} . 9. moving bed method according to claim 1 is characterized in that, in terms of catalyst mass in the first reactor, the feed mass space velocity of the first batch of raw materials methanol and/or dimethyl ether is 1-5h ^{− 1} . 10. moving bed method according to claim 1, is characterized in that, the feed amount of described second batch and described third batch of raw material methanol and/or dimethyl ether and described first batch of raw material methanol and/or Or the molar ratio of the feeding amount of dimethyl ether is 0.1～1:1, respectively. 11. moving bed method according to claim 1, is characterized in that, the feed amount of described second batch and described third batch of raw material methanol and/or dimethyl ether and described first batch of raw material methanol and/or Or the molar ratio of the feed amount of dimethyl ether is 0.1-0.5:1, respectively. 12 . The moving bed method according to claim 1 , wherein the moving bed in which a plurality of reactors are connected in series comprises three or more reactors in series. 13 .

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