Method for preparing vinyl alkyl ether by dealcoholizing ethylene glycol dialkyl ether

Abstract

The method comprises the following steps: enabling ethylene glycol dialkyl ether ROCH2CH2OR to pass through a bed filled with a supported calcium oxide catalyst, and reacting under the reaction conditions that the temperature is 350-480 DEG C, the pressure is 0.01-1.00 MPa, the weight space velocity of ethylene glycol dialkyl ether liquid is 0.1-5.0 h <-1 > and the volume space velocity of diluted gas is 0-2000h <-1 >, so as to obtain the vinyl alkyl ether. And preparing the vinyl alkyl ether CH2 = CHOR. By adopting the granular catalyst and the continuous reaction process, the process is efficient, safe, clean and environment-friendly; the catalytic reaction activity and selectivity are high, the material consumption and energy consumption are low, and the device can be large-sized.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of organic chemical industry, and particularly relates to a method for preparing a vinyl alkyl ether by dealcoholizing an ethylene glycol dialkyl ether. BACKGROUND

[0002] Vinyl alkyl ether, also known as alkyl vinyl ether, is an important organic chemical intermediate and polymer monomer. Common vinyl alkyl ethers include vinyl methyl ether, ethyl ether and n-butyl ether, vinyl trifluoromethyl ether, trifluoroethyl ether, heptafluoropropyl ether, vinyl-2-hydroxyethyl ether, vinyl-4-hydroxybutyl ether, vinyl diethylene glycol monoether or diether, vinyl allyl ether, benzyl ether or furfuryl ether, etc. Vinyl alkyl ethers are widely used as raw materials for various organic compounds such as synthetic resins, adhesives and glutaraldehyde. Since vinyl alkyl ether compounds have broad application prospects, it is of great significance to develop vinyl alkyl ether series products in China.

[0003] At present, the main methods for industrial production of vinyl alkyl ethers at home and abroad are ethyne addition method and acetal pyrolysis method. The ethyne addition method has high reaction temperature and pressure, which makes the raw material ethyne have an explosion risk and is highly dangerous. The production equipment requirements are high, and the single series reaction device is difficult to be large-scale. Liquid strong base catalysts are used in large quantities and are easy to be deactivated, which causes serious environmental pollution. The acetal gas phase cracking method is usually carried out at a high temperature, and the product is relatively complex. Acetal is easy to form peroxide at high temperature, which has an explosion risk.

[0004] The method for preparing vinyl ether by catalytic cracking of ethylene glycol ether as raw material can solve the explosion risk caused by the raw materials of the ethyne method and the acetal method. There have been reports on this method. For example, patents US5650544A, US6090988A and JP3685942B disclose a method for preparing vinyl ether by gas phase dehydration of ethylene glycol monoethyl ether under the action of a Cs2O / SiO2 catalyst. The reaction temperature is 420℃, and the GHSV is 1500h-1. The selectivity of vinyl ether is 84.4%, and the conversion rate of ethylene glycol monoethyl ether is 72.5%. -1 However, the Cs2O / SiO2 catalyst used in this method is expensive, and the Cs species will gradually flow out with the prolongation of the reaction time, which leads to fast deactivation of the catalyst and poor reaction stability, and has limited practical value.

[0005] For example, patent CN111807937B discloses a method for synthesizing vinyl methyl ether from ethylene glycol dimethyl ether: ethylene glycol dimethyl ether undergoes elimination reaction under the catalysis of solid base to obtain vinyl methyl ether and methanol; the solid base is magnesium oxide, cerium dioxide, calcium oxide or calcium-magnesium mixed oxide; in the calcium-magnesium mixed oxide, the molar ratio of calcium to magnesium is 0.1-4; the elimination reaction is carried out in a micro fixed bed reactor under normal pressure; the ethylene glycol dimethyl ether is introduced into the fixed bed reactor in the form of bubbling, and nitrogen is used as the bubbling and balancing gas; the space velocity of the ethylene glycol dimethyl ether is 1.0-10 h -1 Although the raw material source of this invention is extensive and green, and the catalyst is cheap, the single alkaline earth or rare earth oxide catalyst has small specific surface area, low utilization rate of basic active center, and is easy to form carbonate and lose activity, resulting in short service life of the catalyst.

[0006] For example, patent CN115772069A provides a synthesis method of vinyl methyl ether, which uses sodium or potassium alkali, diphenyl furan and ethylene glycol dimethyl ether as reaction raw materials in a molar ratio of 1:0.5-1:0.5-10, and the alkali metal is added in solid or molten state, and the reaction is carried out at a temperature of 60-150℃, a pressure of 0.05-0.30 MPa for 1.5-4.0 h to obtain vinyl methyl ether. Although it solves the problems of high reaction temperature and low yield of vinyl methyl ether in the prior art, the use of a large amount of alkali metal as a catalyst brings greater safety hazards: on the one hand, the alkali metal is added in solid or molten state, which is difficult to quickly disperse or dissolve into the reaction system, resulting in uneven distribution of the catalyst and easy to cause local intense reaction and large heat release; on the other hand, the purity of raw materials and solvents is extremely high and cannot tolerate substances with active hydrogen such as water or alcohol, even so, the methanol generated in the reaction will react with the alkali metal to generate alkali metal alcoholate and release hydrogen, so there is a serious safety risk; in addition, the generation of alkali metal alcoholate will also lead to the decrease of the yield of byproduct methanol and environmental pollution.

[0007] Therefore, there is still an unmet need for developing a safer, more effective, economic or environmentally friendly preparation process of vinyl alkyl ether. SUMMARY

[0008] In view of the defects of the prior art, the present application provides a method for preparing vinyl alkyl ether by de-alkylation of ethylene glycol dialkyl ether, which uses a new type of catalyst with relatively low price and high reaction activity, product selectivity and stability, and ethylene glycol dialkyl ether raw material with extensive source, aiming to realize the preparation of vinyl alkyl ether with safety, effectiveness, economy, environmental protection and high selectivity of target product.

[0009] In one aspect, the present application provides a method for preparing a vinyl alkyl ether by de- alkylation of an ethylene glycol dialkyl ether, the reaction formula of which is shown in formula (I), and the catalyst for the reaction is x(Ca 1.0 A a B b O c )-yG / zZ;

[0010] ROCH2CH2OR → CH2=CHOR + H2O(Ⅰ);

[0011] In formula (I), R is a hydrocarbon group or a derivative thereof;

[0012] In the catalyst, Ca 1.0 A a B b O c is a main catalyst, Z is a carrier, A is at least one element selected from Mg, Sr, Ba, Ga, In, Ge and Sn, B is at least one element selected from rare earth metals, and O is an oxygen element; G is a modifying additive selected from at least one substance from Si, BN, AlN, GaN, C3N4, Si3N4, SiC or Fe3C; Z comprises at least one substance selected from SiO2, Al2O3, TiO2, ZrO2, a full-silica molecular sieve and a metal ion-exchanged molecular sieve; in the main catalyst, 1.0, a, b and c respectively represent the molar ratio of Ca, A, B and O in the main catalyst, a = 0~5.0, b = 0~0.5; x, y and z respectively represent the mass fraction of the main catalyst, the modifying additive and the carrier in the catalyst; x = 30~98%, y = 2~25%, z = 0~68%.

[0013] Preferably, c is a value satisfying the valence requirements of Ca, A and B.

[0014] Preferably, A is at least one element selected from Mg, Ba, In, Ge or Sn, B is at least one element selected from Sc, Y, La, Ce, Nd, Sm, Yb or Th; G is at least one substance selected from Si, BN, AlN, C3N4, Si3N4 or SiC; the full-silica molecular sieve is selected from S-1, S-2, MCM-41, MCM-48 and SBA-15; the metal ion-exchanged molecular sieve is an alkaline earth or rare earth metal ion-exchanged molecular sieve ZSM-5 and / or MCM-22; a = 0, b = 0, a = 0.10~3.00, b = 0, a = 0, b = 0.005~0.20, or a = 0.10~3.00, b = 0.01~0.20; x = 40~96%, y = 3~20% and z = 0~57%.

[0015] In one or more embodiments, A is selected from one or more of Mg, In and Ge, B is selected from one or more of La and Ce; G is selected from one of Si, C3N4, Si3N4and SiC; Z is selected from one of silica gel, MgZSM-5, CaZSM-11, LaMCM-22, S-1 (Silicalite-1) and SBA-15; a = 0, b = 0, a = 0.20-2.00, b = 0, a = 0, b = 0.01-0.10, or a = 0.20-2.00, b = 0.02-0.10; x = 50-95%, y = 4-15% and z = 0-46%.

[0016] In one or more embodiments, the reactor employed for the reaction is a fixed bed reactor or a fluidized bed reactor.

[0017] In one or more embodiments, R is C1-C6 alkyl or C1-C 12 fluoroalkyl.

[0018] Preferably, R is methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, perfluoromethyl, trifluoroethyl ether, pentafluoropropyl, heptafluorobutyl, perfluorohexylpropyl or perfluorooctylpropyl.

[0019] In one or more embodiments, the feed of the reaction further comprises a dilution gas, the conditions of the reaction are temperature 380-460°C, pressure 0.05-0.75 MPa, weight hourly space velocity of the ethylene glycol dialkyl ether feed liquid 0.2-2.5 h -1 and volume hourly space velocity of the dilution gas feed gas 0-2500 h -1 .

[0020] Preferably, the conditions of the reaction are temperature 400-440°C, pressure 0.10-0.50 MPa, weight hourly space velocity of the ethylene glycol dialkyl ether feed liquid 0.3-1.5 h -1 and volume hourly space velocity of the dilution gas feed gas 0-1500 h -1 .

[0021] In one or more embodiments, the diluting gas is N2, H2O, CO2, CH4, H2, N2-H2O, N2-CO2, N2-CH4, N2-H2, H2O-CO2, H2O-CH4, H2O-H2, CO2-CH4, CO2-H2, CH4-H2, N2-H2O-CO2, N2-H2O-CH4, N2-H2O-H2, H2O-CO2-CH4, H2O-CO2-H2, CO2-CH4-H2, N2-H2O-CO2-CH4, N2-H2O-CO2-H2, N2-CO2-CH4-H2, H2O-CO2-CH4-H2, N2-H2O-CO2-CH4-H2, oxygen-deficient air, oxygen-containing N2, oxygen-containing CO2, or industrial exhaust gas.

[0022] Preferably, the O2 content in the oxygen-deficient air, oxygen-containing CO2, and industrial exhaust gas is ≤2 vol%; preferably, the organic matter content in the industrial exhaust gas is ≤500 ppm.

[0023] Preferably, the diluting gas is N2, N2-H2O, N2-CO2, N2-H2O-CO2, oxygen-deficient air, oxygen-containing N2, or industrial exhaust gas.

[0024] In one or more embodiments, a > 0, b = 0, z = 0, and A is selected from at least one element chosen from Mg, Sr, and Ba; the catalyst x(Ca 1.0 A a B b O c )-yG / zZ is prepared by the following steps:

[0025] S1: Ca(OH)2 or a mixture of Ca(OH)2 and A(OH)2 is placed in flowing air and calcined at 500~600℃ for 2.0~3.0h and 700~800℃ for 3.0~5.0h to obtain CaO or CaO-AO powder;

[0026] S2: Add the modifying agent G, pore-forming agent, and binder to the CaO or CaO-AO powder obtained in step S1, mix evenly, and then form granules by spray drying, extrusion molding, or sheet forming. Then, calcine the granules in flowing air at 300-400℃ for 1.0-2.0h and 500-550℃ for 3.0-5.0h to obtain the catalyst x(Ca 1.0 A a B b O c )-yG / zZ particles.

[0027] In one or more embodiments, a > 0, b = 0, z > 0, and A is selected from at least one element chosen from Mg, Sr, and Ba; the catalyst x(Ca 1.0 A a B b O c )-yG / zZ is prepared by the following steps:

[0028] S1: Add Ca(OH)2 or a mixture of Ca(OH)2 and A(OH)2 to support Z, add deionized water and stir at 35~60℃ for 0.5~2.0h to form a slurry, evaporate to dryness, pulverize and mix, and then place in flowing air for calcination at 300~400℃ for 1.0~2.0h, 500~600℃ for 2.0~3.0h and 700~800℃ for 3.0~5.0h to obtain powder of supported main catalyst;

[0029] S2: Add the modifying agent G, pore-forming agent, and binder to the powder of the supported main catalyst obtained in step S1, mix evenly, and then form granules by spray drying, extrusion molding, or sheet forming. Then, calcine the granules in flowing air at 300-400℃ for 1.0-2.0h and 500-550℃ for 3.0-5.0h to obtain the catalyst x(Ca). 1.0 A a B b O c )-yG / zZ particles.

[0030] In one or more embodiments, a > 0, b ≥ 0, z > 0; the catalyst x (Ca 1.0 A a B b O c )-yG / zZ is prepared by the following steps:

[0031] S1: The carrier Z is impregnated with an equal volume of nitrate aqueous solution of B and / or A selected from non-alkaline earth metal elements at 35~60℃, evaporated to dryness, pulverized and mixed, and placed in flowing air for calcination at 300~400℃ for 1.0~2.0h, 500~600℃ for 2.0~3.0h and 700~800℃ for 3.0~5.0h to obtain a carrier powder loaded with auxiliary oxides;

[0032] S2: Add Ca(OH)2 or a mixture of Ca(OH)2 and a hydroxide selected from alkaline earth metal element A to the carrier powder of the supported oxide promoter obtained in step S1, add water and stir for 0.5~2.0h to form a slurry and keep the slurry at 35~60℃, evaporate to dryness, crush and mix evenly, place in flowing air and calcine at 300~400℃ for 1.0~2.0h, 500~600℃ for 2.0~3.0h and 700~800℃ for 3.0~5.0h to obtain the powder of the supported main catalyst;

[0033] S3: Add the modifying agent G, pore-forming agent, and binder to the powder of the supported main catalyst obtained in step S2, mix evenly, and then form granules by spray drying, extrusion, or flaking. Then, calcine the granules in flowing air at 300-400℃ for 1.0-2.0h and 500-550℃ for 3.0-5.0h to obtain the catalyst x(Ca). 1.0 A a B b O c )-yG / zZ particles.

[0034] Preferably, the catalyst x(Ca) 1.0 A a B b O c The particles of )-yG / zZ are microspheres with a diameter of 30~500μm, cylinders with a diameter of 2~5mm and a length of 3~8mm, or irregularly shaped particles with a diameter of 2~5mm and a length of 3~8mm. More preferably, the catalyst x(Ca 1.0 A a B b O c The particles of )-yG / zZ are microspheres with a diameter of 50~300μm, cylinders with a diameter of 2~4mm and a length of 3~5mm, or clover-shaped particles with a diameter of 2~4mm and a length of 3~5mm. More preferably, the catalyst x(Ca 1.0 A a B b O c The particles of )-yG / zZ are microspheres with a diameter of 100~200μm or clover particles with a diameter of 2~3mm and a length of 3~4mm.

[0035] Preferably, the pore-forming agent is at least one selected from water, nitric acid, acetic acid, citric acid, triglyceride, ethylene glycol, glycerol, and vegetable oil, and is added in an amount of 1-10 wt% of the metal oxide or the powder supporting the main catalyst. More preferably, the pore-forming agent is water, nitric acid, citric acid, or glycerol, and is added in an amount of 2-5 wt% of the metal oxide or the powder supporting the main catalyst.

[0036] Preferably, the binder is at least one selected from guar gum powder, methylcellulose, polyethylene glycol (PEG), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), or starch, and the amount added is 2-20 wt% of the metal oxide or the powder supported on the main catalyst. More preferably, the binder is guar gum powder, methylcellulose, PEG 200-2000, or starch, and the amount added is 5-10 wt% of the metal oxide or the powder supported on the main catalyst.

[0037] Preferably, the method further includes a catalyst x (Ca 1.0 A a B b O c Preparation of )-yG / zZ.

[0038] In another aspect, catalyst x (Ca 1.0 A a B b O c Application of )-yG / zZ in the catalytic dehydration of ethylene glycol dialkyl ethers to prepare vinylalkyl ethers, wherein the catalyst contains Ca 1.0 A a B b O c Z is the main catalyst, and A is the support. A is at least one element selected from Mg, Sr, Ba, Ga, In, Ge, and Sn; B is at least one element selected from rare earth metals; and O is oxygen. G is a modifier selected from at least one substance selected from elemental Si, BN, AlN, GaN, C3N4, Si3N4, SiC, or Fe3C. Z contains at least one substance selected from SiO2, Al2O3, TiO2, ZrO2, all-silica molecular sieves, and metal ion-exchange molecular sieves. In the main catalyst, 1.0, a, b, and c represent the molar ratios of the corresponding elements Ca, A, B, and O in the main catalyst, respectively, where a = 0~5.0 and b = 0~0.5. x, y, and z represent the mass fractions of the main catalyst, modifier, and support in the catalyst, respectively, where x = 30~98%, y = 2~25%, and z = 0~68%.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] 1. This invention uses ethylene glycol dialkyl ether as raw material to prepare vinyl alkyl ether through gas-phase catalytic dehydration. This avoids the safety risks of raw material explosion and environmental pollution caused by liquid catalysts in the current industrial production of vinyl ether using the acetylene addition method, as well as the safety risks of raw material acetal forming peroxides in the acetal gas-phase cracking method. The reaction process is green and safe, in line with the concept of sustainable development. It can not only solve the problem of overcapacity of coal-based ethylene glycol in my country and promote the healthy development of the coal chemical industry, but also promote the progress of my country's vinyl ether and polyether industries.

[0041] 2. This invention improves the structural stability of calcium oxide catalysts and their ability to activate ethylene glycol dialkyl ethers at the base sites by adding metal oxide additives, modifying additives, and porous supports. It also uses a highly dispersed main catalyst and improves its utilization rate and raw material adsorption capacity. This gives the calcium composite oxide catalyst high activity, selectivity, and stability for the ethylene glycol dialkyl ether cracking reaction, overcoming the problem of easy deactivation and short lifespan of existing ethylene glycol dialkyl ether cracking catalysts.

[0042] 3. The catalyst used in this invention is simple and inexpensive to prepare, has high reaction stability, and can withstand high raw material concentrations and space velocities, requiring only a small amount of catalyst. The raw material, ethylene glycol dialkyl ether, is inexpensive and readily available, and can be obtained by etherifying petroleum-based ethylene oxide or coal-based ethylene glycol produced on a large industrial scale with alkanols. The alkanols generated in the reaction can be recycled for the preparation of the raw material ethylene glycol dialkyl ether, resulting in high effective utilization of the raw materials. Detailed Implementation

[0043] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Unless otherwise specified, all experimental materials used in the following examples are commercially available.

[0045] In the following embodiments, the main process for preparing vinyl ether from ethylene glycol dialkyl ether by dehydration includes: filling the constant temperature section of the reaction tube with catalyst, and filling the reaction tube with quartz sand-catalyst-quartz sand in sequence from top to bottom; conveying the raw material to the preheater by a horizontal flow pump, heating and vaporizing it, and then sending it into the reactor.

[0046] In the following embodiments, the detection and statistical methods related to the reaction products of the preparation of vinyl ethers from ethylene glycol dialkyl ethers are as follows: the reaction products are sent to a gas chromatograph equipped with an FID detector and an RTx-624 capillary column for online analysis, and the conversion rate X of ethylene glycol dialkyl ethers and the selectivity S of vinyl alkyl ethers are calculated using the corrected area normalization method, as shown in the following formula:

[0047]

[0048]

[0049] Example 1: Catalysis of ethylene glycol dimethyl ether de-alcoholization reaction using a catalyst with added modifiers

[0050] Preparation of a demethanation catalyst

[0051] S1: According to the catalyst composition elements and stoichiometric ratios listed in Table 1, Ca(OH)2 or a mixture of Ca(OH)2 and Mg(OH)2 is placed in flowing air and calcined at 550℃ for 2.0~3.0h and 750℃ for 5.0h to obtain CaO or CaO-MgO powder.

[0052] S2: According to the catalyst composition elements and stoichiometric ratios listed in Table 1, add C3N4, a modifying agent with a particle size of less than 200 nm, to the CaO or CaO-MgO powder obtained in step S1, and add 2.5 wt% citric acid, a pore-forming agent, and 5 wt% methylcellulose, a binder, based on the weight of the CaO or CaO-MgO powder. After mixing evenly, form the mixture into clover-shaped particles with a diameter of 2.6 mm and a length of 3.0 mm. Then, calcine the particles in flowing air at 350 °C for 2.0 h and 550 °C for 5.0 h to obtain catalyst particles with added modifying agents.

[0053] Ethylene glycol dimethyl ether demethanation reaction

[0054] Ethylene glycol dimethyl ether and diluent gas N2 are fed into a preheater and heated to the reaction temperature. Then, they are fed into a micro-fixed-bed reactor packed with small-particle catalyst (crushed to 40-60 mesh). The reaction is carried out at 400℃, 0.1 MPa, and a liquid weight hourly space velocity (WHSV) of 0.5 h⁻¹. -1 When diluted with N2 gas, the volume hourly space velocity is 500 h⁻¹. -1 Under the specified conditions, the de-alcoholization reaction of ethylene glycol dimethyl ether was carried out for 10 h, and the reaction results are shown in Table 1.

[0055] Example 2: Catalysis of ethylene glycol dimethyl ether de-alcoholization reaction using a catalyst with added modifiers and support

[0056] Preparation of a demethanation catalyst

[0057] S1: According to the catalyst composition elements and stoichiometry listed in Table 1, Ca(OH)2 powder was added to the silica gel support, and deionized water was added and stirred at 50℃ for 1h to make a slurry. After evaporation, the slurry was pulverized and mixed, placed in flowing air, and calcined at 350℃ for 1.0h, 550℃ for 2.0h, and 750℃ for 5.0h to obtain the powder of the supported main catalyst.

[0058] S2: According to the catalyst composition elements and stoichiometry listed in Table 1, add C3N4, a modifier with a particle size of less than 200 nm, to the powder of the supported main catalyst obtained in step S1, and add 2.5 wt% citric acid, a pore-forming agent, and 5 wt% methylcellulose, a binder, based on the weight of the powder of the supported main catalyst. After mixing evenly, form the mixture into clover-shaped particles with a diameter of 2.6 mm and a length of 3.0 mm. Then, calcine the particles in flowing air at 350 °C for 2.0 h and 550 °C for 5.0 h to obtain catalyst particles with added modifiers and supports.

[0059] Ethylene glycol dimethyl ether demethanation reaction

[0060] Ethylene glycol dimethyl ether and diluent gas N2 are fed into a preheater and heated to the reaction temperature. Then, they are fed into a micro-fixed-bed reactor packed with small-particle catalyst (crushed to 40-60 mesh). The reaction is carried out at 400℃, 0.1 MPa, and a liquid weight hourly space velocity (WHSV) of 0.5 h⁻¹. -1 When diluted with N2 gas, the volume hourly space velocity is 500 h⁻¹. -1 Under the specified conditions, the de-alcoholization reaction of ethylene glycol dimethyl ether was carried out for 10 h, and the reaction results are shown in Table 1.

[0061] Examples 3-5: Catalysis of ethylene glycol dimethyl ether de-alcoholization reaction using catalysts with added oxide and modifying agents

[0062] Preparation of a demethanation catalyst

[0063] S1: According to the catalyst composition elements and stoichiometry listed in Table 1, a uniform powder mixture of Ca(OH)2 and Mg(OH)2 is placed in flowing air and calcined at 550℃ for 3.0h and 750℃ for 5.0h to obtain CaO or CaO-MgO powder.

[0064] S2: According to the catalyst composition elements and stoichiometric ratios listed in Table 1, add C3N4, a modifying agent with a particle size of less than 200 nm, to the CaO-MgO powder obtained in step S1, and add 2.5 wt% citric acid, a pore-forming agent, and 5 wt% methylcellulose, a binder, based on the weight of the CaO-MgO powder. After mixing evenly, form clover-shaped particles with a diameter of 2.6 mm and a length of 3.0 mm. Then, calcine them in flowing air at 350°C for 2.0 h and 550°C for 5.0 h to obtain catalyst particles with added oxide and modifying agents.

[0065] Ethylene glycol dimethyl ether demethanation reaction

[0066] Ethylene glycol dimethyl ether and diluent gas N2 were fed into a preheater and heated to the reaction temperature. Then, the mixture was fed into a micro-fixed-bed reactor packed with small-particle catalyst (crushed to 40-60 mesh). The reaction was carried out at a temperature of 420℃, a pressure of 0.2 MPa, and a liquid weight hourly space velocity (WHSV) of 1.0 h⁻¹ for ethylene glycol dimethyl ether. -1 When diluted with N2 gas, the volume hourly space velocity is 1000 h⁻¹ -1 Under the specified conditions, the de-alcoholization reaction of ethylene glycol dimethyl ether was carried out for 10 h, and the reaction results are shown in Table 1.

[0067] Example 6: Catalysis of ethylene glycol dimethyl ether de-alcoholization reaction using a catalyst with added oxide additives, modifiers, and support.

[0068] Preparation of a demethanation catalyst

[0069] S1: According to the catalyst composition elements and stoichiometry listed in Table 1, a uniform powder mixture of Ca(OH)2 and Mg(OH)2 was added to the silica gel support, and deionized water was added and stirred at 50°C for 1 h to form a slurry. After evaporation, the slurry was pulverized and mixed, placed in flowing air, and calcined at 350°C for 1.0 h, 550°C for 2.0 h, and 750°C for 5.0 h to obtain the powder of the supported main catalyst.

[0070] S2: According to the catalyst composition elements and stoichiometry listed in Table 1, add the modified auxiliary agent C3N4 with a particle size of less than 200nm to the powder of the supported main catalyst obtained in step S1, and add 2.5wt% of pore-forming agent citric acid and 5wt% of binder methylcellulose based on the weight of the powder of the supported main catalyst. After mixing evenly, form into clover-shaped particles with a diameter of 2.6mm and a length of 3.0mm. Then calcine in flowing air at 350℃ for 2.0h and 550℃ for 5.0h to obtain catalyst particles with oxide auxiliary agent, modified auxiliary agent and support.

[0071] Ethylene glycol dimethyl ether demethanation reaction

[0072] Ethylene glycol dimethyl ether and diluent gas N2 were fed into a preheater and heated to the reaction temperature. Then, the mixture was fed into a micro-fixed-bed reactor packed with small-particle catalyst (crushed to 40-60 mesh). The reaction was carried out at a temperature of 420℃, a pressure of 0.2 MPa, and a liquid weight hourly space velocity (WHSV) of 1.0 h⁻¹ for ethylene glycol dimethyl ether. -1 When diluted with N2 gas, the volume hourly space velocity is 1000 h⁻¹ -1 Under the specified conditions, the de-alcoholization reaction of ethylene glycol dimethyl ether was carried out for 10 h, and the reaction results are shown in Table 1.

[0073] Table 1 shows that catalysts with at least one of the following components—oxide promoter (MgO), modifying promoter (C3N4), and support (SiO2)—all exhibit good reactivity for the demethanolization of ethylene glycol dimethyl ether to vinyl methyl ether, with a weight hourly space velocity (WHSV) of 0.5–1.0 h⁻¹ in liquid ethylene glycol dimethyl ether at temperatures of 400–420 °C, pressures of 0.1–0.2 MPa, and WHSVs of 0.5–1.0 h⁻¹. -1 When diluted with N2 gas, the volumetric hourly space velocity is 500~1000 h⁻¹. -1 Under the specified conditions, the de-alcoholization reaction of ethylene glycol dimethyl ether was carried out for 10 hours, and the conversion rate of ethylene glycol dimethyl ether was 82.6-96.5%, while the selectivity of vinyl alkyl ether (vinyl methyl ether) was 96.3-99.9%.

[0074] Comparative Examples 1-2: Catalysis of ethylene glycol dimethyl ether deethanolination reaction by catalysts without the addition of modifiers or supports

[0075] Preparation of a demethanation catalyst

[0076] S1: According to the catalyst composition elements and stoichiometric ratios listed in Table 1, Ca(OH)2 or a homogeneous mixture of Ca(OH)2 and Mg(OH)2 in a molar ratio of 1.0:1.0 is placed in flowing air and calcined at 550℃ for 2.0 h and 750℃ for 5.0 h to obtain CaO or Ca 1.0 Mg 1.0 O 2.0 powder;

[0077] S2: According to the catalyst composition elements and stoichiometry listed in Table 1, add the modifying agent C3N4 with a particle size of less than 200 nm, 2.5 wt% of the pore-forming agent citric acid, and 5 wt% of the binder methylcellulose to the CaO or CaO obtained in step S1. 1.0 Mg 1.0 O 2.0 The powder is mixed evenly and then shaped into clover-shaped particles with a diameter of 2.6 mm and a length of 3.0 mm. The particles are then calcined in flowing air at 350°C for 2.0 h and 550°C for 5.0 h to obtain catalyst particles.

[0078] Ethylene glycol dimethyl ether demethanation reaction

[0079] The operating procedure and process conditions for Comparative Example 1 were the same as those for Example 1, and the operating procedure and process conditions for Comparative Example 2 were the same as those for Example 4. The results after 10 hours of reaction are shown in Table 1. As can be seen from Table 1, the conversion rate of ethylene glycol dimethyl ether in Comparative Example 1 was 78.8% and the selectivity of vinyl methyl ether was 90.6%, while the conversion rate of ethylene glycol dimethyl ether in Comparative Example 2 was 82.2% and the selectivity of vinyl methyl ether was 98.5%.

[0080] Comparing Examples 1 and 2 with Comparative Example 1, it can be seen that the catalyst with modified additive C3N4 (Example 1) and the catalyst with modified additive C3N4 and support SiO2 (Example 2) are significantly better than the catalyst without modified additive and support. 1.0 O 1.0 (Comparative Example 1) The conversion rates of ethylene glycol dimethyl ether increased by 4.8% and 8.5% respectively, and the selectivity of vinyl methyl ether increased by 6.3% and 6.5% respectively. Comparing Examples 4 and 6 with Comparative Example 2, it can also be found that the catalysts with added modifier C3N4 (Example 4) and the catalysts with added modifier C3N4 and support SiO2 (Example 6) are significantly better than the catalysts without added modifiers and support. 1.0 Mg 1.0 O 2.0 (Comparative Example 2) The conversion rates of ethylene glycol dimethyl ether were increased by 10.1% and 11.7% respectively, and the selectivity of vinyl methyl ether was increased by 1.4% and 1.1% respectively.

[0081] Examples 7-8: Catalysis of ethylene glycol diethyl ether de-alcoholization reaction using catalysts with added modifiers and supports

[0082] Preparation of a deethanation catalyst

[0083] S1: According to the catalyst composition elements and stoichiometry listed in Table 1, add the uniform powder mixture of Ca(OH)2 and Mg(OH)2 to the silica gel support or SBA-15 support, add deionized water and stir at 50℃ for 1h to make a slurry, evaporate to dryness, pulverize and mix, place in flowing air, and calcine at 350℃ for 2.0h, 550℃ for 2.0h and 750℃ for 5.0h to obtain the powder of the supported main catalyst;

[0084] S2: According to the catalyst composition elements and stoichiometry listed in Table 1, add the modified auxiliary agent C3N4 with a particle size of less than 200nm, 2.5wt% of the pore-forming agent citric acid and 5wt% of the binder methylcellulose to the powder of the supported main catalyst obtained in step S1. After mixing evenly, the mixture is sheeted into clover-shaped particles with a diameter of 2.6mm and a length of 3.0mm. Then, the particles are calcined in flowing air at 350℃ for 2.0h and 550℃ for 5.0h to obtain catalyst particles.

[0085] Ethylene glycol diethyl ether deethanation reaction

[0086] Ethylene glycol diethyl ether and diluent gas N2 were fed into a preheater and heated to the reaction temperature. Then, the mixture was fed into a micro-fixed-bed reactor packed with small-particle catalyst (crushed to 40-60 mesh). The reaction was carried out at a temperature of 440℃, a pressure of 0.3 MPa, and a liquid weight hourly space velocity (WHSV) of 0.75 h⁻¹. -1 The volumetric space velocity (VHSV) of N2 gas is 750 h⁻¹.-1 The reaction was carried out under the specified conditions for 10 hours, and the results are shown in Table 1.

[0087] Example 9: Catalysis of ethylene glycol diethyl ether de-alcoholization reaction using catalysts with added oxide auxiliaries and modifiers

[0088] Preparation of a deethanation catalyst

[0089] S1: According to the catalyst composition elements and stoichiometric ratios listed in Table 1, impregnate the corresponding support with an equal volume of La nitrate aqueous solution at 50℃, evaporate to dryness, pulverize and mix, place in flowing air, and calcine at 350℃ for 2.0h and 600℃ for 5.0h to obtain the support powder with oxide additives.

[0090] S2: According to the catalyst composition elements and stoichiometry listed in Table 1, add Ca(OH)2 powder to the carrier powder of the supported oxide promoter obtained in step S1, add deionized water at 50°C and stir for 1.0 h to make a slurry, evaporate to dryness, crush and mix evenly, place in flowing air and calcine at 350°C for 2.0 h, 550°C for 2.0 h and 750°C for 5.0 h to obtain the powder of the supported main catalyst;

[0091] S3: According to the catalyst composition elements and stoichiometry listed in Table 1, add the modified auxiliary agent C3N4 with a particle size of less than 200nm, 2.5wt% of the pore-forming agent citric acid and 5wt% of the binder methylcellulose to the powder of the supported main catalyst obtained in step S2. After mixing evenly, the mixture is sheeted into clover-shaped particles with a diameter of 2.6mm and a length of 3.0mm. Then, it is calcined in flowing air at 350℃ for 2.0h and 550℃ for 5.0h to obtain catalyst particles.

[0092] Ethylene glycol diethyl ether deethanation reaction

[0093] Ethylene glycol diethyl ether and diluent gas N2 were fed into a preheater and heated to the reaction temperature. Then, the mixture was fed into a micro-fixed-bed reactor packed with small-particle catalyst (crushed to 40-60 mesh). The reaction was carried out at a temperature of 440℃, a pressure of 0.3 MPa, and a weight hourly space velocity (WHSV) of 0.75 h⁻¹ for ethylene glycol dimethyl ether. -1 N2 volume hourly space velocity 750 h⁻¹ -1 The de-alcoholization reaction of ethylene glycol diethyl ether was carried out under the conditions for 10 h, and the reaction results are shown in Table 1.

[0094] Examples 10-12: Catalysis of ethylene glycol diethyl ether de-alcoholization reaction with the addition of oxide auxiliaries, modifying auxiliaries and supported catalysts

[0095] Preparation of a deethanation catalyst

[0096] S1: According to the catalyst composition elements and stoichiometric ratios listed in Table 1, impregnate the corresponding support with an equal volume of an aqueous solution of In, Ge and / or La, Ce nitrates at 50°C, evaporate to dryness, pulverize and mix, place in flowing air, and calcine at 350°C for 2.0 h and 600°C for 5.0 h to obtain the support powder with supported oxide additives.

[0097] S2: According to the catalyst composition elements and stoichiometric ratios listed in Table 1, add the uniform powder mixture of Ca(OH)2 or Ca(OH)2 and Mg(OH)2 to the carrier powder of the supported oxide promoter obtained in step S1, add deionized water at 50°C and stir for 1.0 h to form a slurry, evaporate to dryness, pulverize and mix, and place in flowing air for calcination at 350°C for 2.0 h, 550°C for 2.0 h and 750°C for 5.0 h to obtain the powder of the supported main catalyst;

[0098] S3: According to the catalyst composition elements and stoichiometry listed in Table 1, add the modified auxiliary agent C3N4 with a particle size of less than 200nm, 2.5wt% of the pore-forming agent citric acid and 5wt% of the binder methylcellulose to the powder of the supported main catalyst obtained in step S2. After mixing evenly, the mixture is sheeted into clover-shaped particles with a diameter of 2.6mm and a length of 3.0mm. Then, it is calcined in flowing air at 350℃ for 2.0h and 550℃ for 5.0h to obtain catalyst particles.

[0099] Ethylene glycol diethyl ether deethanation reaction

[0100] Ethylene glycol diethyl ether and diluent gas N2 were fed into a preheater and heated to the reaction temperature. Then, the mixture was fed into a micro-fixed-bed reactor packed with small-particle catalyst (crushed to 40-60 mesh). The reaction was carried out at 420℃, 0.2 MPa, and a liquid weight hourly space velocity (WHSV) of 1.0 h⁻¹ for ethylene glycol dimethyl ether. -1 When mixed with N2 gas, the volumetric space velocity is 1000 h⁻¹ -1 The de-alcoholization reaction of ethylene glycol diethyl ether was carried out under the conditions for 10 h, and the reaction results are shown in Table 1.

[0101] As shown in Table 1, the conversion rate of ethylene glycol diethyl ether and the selectivity of vinyl ethyl ether in Examples 7-9 were 89.6-95.7% and 97.3-99.3%, respectively, while those in Examples 10-12 were 82.8-85.6% and 97.8-98.5%, respectively. Clearly, catalysts with at least one of the following components—oxides of Mg, Mg-La, In-La, or Ge-Ce, modified agents (C3N4, SiC, Si3N4, or Si), and supports (SiO2, all-silica molecular sieve SBA-15, LaMCM-22, MgZSM-5, or CaZSM-11)—all exhibit good reactivity and selectivity for the deethanolination of ethylene glycol diethyl ether to vinyl ethyl ether.

[0102] Examples 13-16: Dealkylation reactions of different ethylene glycol dialkyl ethers catalyzed by the same catalyst

[0103] Preparation of a deethanation catalyst

[0104] Catalyst 95wt% Ca 1.0 Mg 1.0 O 2.0 The preparation method of -5wt%C3N4 is the same as that of the catalyst in Example 4 (90wt% Ca). 1.0 Mg 1.0 O 2.0 -10wt%C3N4, the difference being that the weight ratio of the main catalyst to the auxiliary agent C3N4 is changed from 90:10 to 95:5.

[0105] Ethylene glycol diethyl ether deethanation reaction

[0106] Ethylene glycol dialkyl ethers (dipropyl ether, dibutyl ether, di(perfluoromethyl ether) or di(trifluoroethyl ether)) are fed into a preheater along with diluent gas N2 and heated to the reaction temperature. Then, they are fed into a micro-fixed-bed reactor packed with small-particle catalyst (catalyst particles crushed to 40-60 mesh). The reaction is carried out at a temperature of 400℃, a pressure of 0.1 MPa, and a liquid weight hourly space velocity (WHSV) of 0.5 h⁻¹. -1 Volumetric space velocity (VHSV) of N2 gas is 500 h⁻¹ -1 The dealkanolization reaction of ethylene glycol dialkyl ether was carried out under the conditions for 10 h, and the reaction results are shown in Table 1.

[0107] Table 1 shows that using the same catalyst with added oxide additives and modifiers, 95wt% Ca 1.0 Mg 1.0 O 2.0 -5wt% C3N4 exhibits excellent reactivity and selectivity for the dealkanization reaction of ethylene glycol dialkyl ethers and ethylene glycol difluoroalkyl ethers under the same reaction process conditions, with conversion rates of 83.2~88.3% and vinyl alkyl ether selectivity of 97.5~99.2%, respectively.

[0108] Examples 17-20: De-alcoholization reaction of ethylene glycol dimethyl ether catalyzed by the same catalyst under different process conditions

[0109] Preparation of a dealkanation catalyst

[0110] The catalyst is 95 wt% Ca. 1.0 Mg 1.0 O 2.0 -5wt% C3N4, prepared using the same method as in Examples 13-16.

[0111] Ethylene glycol dialkyl ether dealkanation reaction Preparation of a demethanation catalyst Ethylene glycol dimethyl ether demethanation reaction

[0112] 95wt% Ca was used with added oxide additives and modifiers. 1.0 Mg 1.0 O 2.0 A micro fixed-bed reactor packed with 5wt% C3N4 catalyst and small particle catalyst was used to investigate the methanol removal performance of ethylene glycol dimethyl ether under different process conditions. The results after 10 h of reaction are shown in Table 1.

[0113] Table 1 shows that the weight hourly space velocity (WHSV) is 0.3–1.0 h⁻¹ when the reaction temperature is 380–440 °C, the pressure is 0.1–0.4 MPa, and the solution is ethylene glycol dimethyl ether. -1 Volumetric hourly space velocity (VHSV) of N2 gas is 0–1500 h⁻¹ -1 Under the given conditions, ethylene glycol dimethyl ether exhibits good reactivity and selectivity, with conversion rates of 82.8–93.5% and vinyl methyl ether selectivity of 99.2–99.5%, respectively.

[0114] Examples 21-22: Stability of the dealcoholization reaction of ethylene glycol dialkyl ethers catalyzed by the same catalyst at different reaction times

[0115] Example 21 uses the catalyst from Examples 13-16 with 95 wt% Ca. 1.0 Mg 1.0 O 2.0 -5wt% C3N4. Ethylene glycol dimethyl ether was fed into a preheater along with nitrogen and heated to the reaction temperature. It was then fed into a fixed-bed single-tube reactor (50mm inner diameter, 3000mm height of the isothermal section) containing 5.0kg of 2.6mm diameter, 3.0mm high cloverleaf catalyst particles. The reaction was carried out at a temperature of 420℃, a pressure of 0.1MPa, and a weight hourly space velocity (WHSV) of 0.5h⁻¹ for the ethylene glycol dimethyl ether feed liquid. -1 Nitrogen gas hourly space velocity 500 h⁻¹ -1 The reaction stability of ethylene glycol dimethyl ether to vinyl methyl ether via methanol removal was investigated. After 10 h, 100 h, and 500 h of catalytic methanol removal reaction, the conversion rates of ethylene glycol dimethyl ether were 91.8%, 91.7%, and 90.8%, respectively, and the selectivity of vinyl methyl ether was 98.8%, 98.8%, and 98.6%, respectively. This indicates that the calcium-based catalyst with added oxide auxiliaries MgO and modified auxiliaries C3N4 exhibits good stability in the methanol removal reaction.

[0116] Example 22 uses the catalyst from Example 10, 70 wt% Ca 1.0 Mg 0.2 La 0.02 O 1.23-6wt% SiC / 24wt% LaMCM-22. Ethylene glycol diethyl ether was fed into a preheater along with nitrogen and heated to the reaction temperature. It was then fed into a fixed-bed single-tube reactor (50mm inner diameter, 3000mm height of the isothermal section) containing 5.0kg of 2.6mm diameter, 3.0mm high cloverleaf catalyst particles. The reaction was carried out at 400℃, 0.2MPa, and a weight hourly space velocity (WHSV) of 0.5h⁻¹ for the ethylene glycol diethyl ether feed liquid. -1 Nitrogen gas hourly space velocity 500 h⁻¹ -1 The reaction stability of ethylene glycol diethyl ether to methanol to vinyl ethyl ether was investigated. After 10 h, 100 h, and 500 h of catalytic deethanolination reaction, the conversion rates of ethylene glycol diethyl ether were 88.6%, 88.6%, and 88.3%, respectively, and the selectivities of vinyl ethyl ether were 97.2%, 97.3%, and 97.1%, respectively. This indicates that the calcium-based catalyst with added oxide promoter MgO-La2O3, modified promoter SiC, and metal ion-exchange molecular sieve support exhibits good stability in the deethanolination reaction.

[0117] Comparative Examples 3-4: Stability of ethylene glycol dialkyl ether dealcoholization reaction with catalysts without added modifiers and supports

[0118] Comparative Example 3 used the catalyst particles of Comparative Example 2 with 100 wt% Ca 1.0 Mg 1.0 O 2.0 The reaction process and operating conditions were the same as in Example 21. After catalytic methanol removal reactions were run for 10 h and 50 h, the conversion rates of ethylene glycol dimethyl ether were 80.3% and 67.2%, respectively, and the selectivity of vinyl methyl ether was 99.8% and 99.7%, respectively. Clearly, without the addition of modifying agents and supports, Ca... 1.0 Mg 1.0 O 2.0 The catalyst activity decreased significantly (by approximately 16.3%) after 50 hours of reaction.

[0119] The catalyst preparation method for Comparative Example 4 was the same as that for Comparative Example 2, except that the molar ratio of MgO to CaO was adjusted from 1.0 to 0.2, and the resulting catalyst particles contained 100 wt% CaO. 1.0 Mg 0.2 O 1.2 The reaction process and operating conditions were the same as in Example 22. After catalytic deethanolization reactions were run for 10 h and 50 h, the conversion rates of ethylene glycol diethyl ether were 83.5% and 68.6%, respectively, and the selectivity of vinyl ethyl ether was 97.6% and 97.3%, respectively. It can be seen that without the addition of modifying agents and supports, Ca... 1.0 Mg 0.2 O 1.2 The catalyst activity decreased significantly (by approximately 17.8%) after 50 hours of reaction.

[0120] In summary, the calcium-based supported catalyst with added oxide promoters, modifiers and / or supports used in this invention exhibits excellent catalytic performance for the dealkanization of ethylene glycol dialkyl ethers to prepare vinyl alkyl ethers. By adding oxide promoters, modifiers and / or porous support materials to the calcium oxide catalyst, not only can the reaction activity be improved, but its reaction stability can also be significantly enhanced.

[0121] Table 1: Process conditions and results of the deethanolization reaction of ethylene glycol dialkyl ethers

[0122]

[0123] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing vinyl alkyl ethers by dealcoholization of ethylene glycol dialkyl ethers, characterized in that, The reaction formula for the preparation of vinyl alkyl ethers from ethylene glycol dialkyl ethers by dealcoholization is shown in formula (I), and the catalyst for the reaction is... x (Ca 1.0 A a B b O c )- y G / z Z; ROCH2CH2OR → CH2=CHOR + H2O (I); In formula (Ⅰ), R is a hydrocarbon group or a derivative thereof; In the catalyst, Ca 1.0 A a B b O c The catalyst is denoted as Z, and the support is denoted as Z. A is at least one element selected from Mg, Sr, Ba, Ga, In, Ge, and Sn; B is at least one element selected from rare earth metals; O is oxygen; G is a modifying agent selected from at least one substance selected from elemental Si, BN, AlN, GaN, C3N4, Si3N4, SiC, or Fe3C; Z contains at least one substance selected from SiO2, Al2O3, TiO2, ZrO2, all-silica molecular sieves, and metal ion-exchange molecular sieves. In the main catalyst, 1.0 , a、b and c These represent the molar ratios of Ca, A, B, and O in the main catalyst, respectively. a = 0~5.0、 b = 0~0.5; x, y and z These represent the mass fractions of the main catalyst, modifying agent, and support in the catalyst, respectively. x =30~98%, y = 2~25%, z =0~68%.

2. The method according to claim 1, characterized in that, A is selected from one or more of Mg, In and Ge; B is selected from one or two of La and Ce; G is selected from one of Si, C3N4, Si3N4 and SiC; Z is selected from one of silica gel, MgZSM-5, CaZSM-11, LaMCM-22, S-1 (Silicalite-1) and SBA-15. a =0、 b = 0, a = 0.20~2.00、 b = 0, a =0、 b =0.01~0.10, or a = 0.20~2.00、 b =0.02~0.10; x = 50~95%, y = 4~15% and z =0~46%.

3. The method according to claim 1, characterized in that, The reaction is carried out in a fixed-bed reactor or a fluidized-bed reactor.

4. The method according to claim 1, characterized in that, R is a C1~C6 alkyl group or a C1~C6 alkyl group. 12 Fluoroalkyl groups.

5. The method according to claim 1, characterized in that, The reaction feed also includes a dilution gas, and the reaction conditions are: temperature 380~460℃, pressure 0.05~0.75MPa, and ethylene glycol dialkyl ether feed liquid weight hourly space velocity 0.2~2.5h. -1 Volumetric hourly space velocity (VHSV) of feed gas and dilution gas is 0~2500 h⁻¹ -1 .

6. The method according to claim 5, characterized in that, The diluting gas is N2, H2O, CO2, CH4, H2, N2-H2O, N2-CO2, N2-CH4, N2-H2, H2O-CO2, H2O-CH4, H2O-H2, CO2-CH4, CO2-H2, CH4-H2, N2-H2O-CO2, N2-H2O-CH4, N2-H2O-H2, H2O-CO2-CH4, H2O-CO2-H2, CO2-CH4-H2, N2-H2O-CO2-CH4, N2-H2O-CO2-H2, N2-CO2-CH4-H2, H2O-CO2-CH4-H2, N2-H2O-CO2-CH4-H2, oxygen-deficient air, oxygen-containing N2 gas, oxygen-containing CO2 gas, or industrial exhaust gas.

7. The method according to claim 1, characterized in that, a >0, b =0, z =0, A is selected from at least one element from Mg, Sr, and Ba; the catalyst x (Ca 1.0 A a B b O c )- y G / z Z is prepared through the following steps: S1: Ca(OH)2 or a mixture of Ca(OH)2 and A(OH)2 is placed in flowing air and calcined at 500~600℃ for 2.0~3.0h and 700~800℃ for 3.0~5.0h to obtain CaO or CaO-AO powder; S2: Add the modifying agent G, pore-forming agent, and binder to the CaO or CaO-AO powder obtained in step S1, mix evenly, and then form granules by spray drying, extrusion molding, or sheet forming. The granules are then calcined in flowing air at 300-400℃ for 1.0-2.0h and 500-550℃ for 3.0-5.0h to obtain the catalyst. x (Ca 1.0 A a B b O c )- y G / z Z particles.

8. The method according to claim 1, characterized in that, a >0, b =0, z >0, A is selected from at least one element selected from Mg, Sr and Ba; the catalyst x (Ca 1.0 A a B b O c )- y G / z Z is prepared through the following steps: S1: Add Ca(OH)2 or a mixture of Ca(OH)2 and A(OH)2 to the support Z, add deionized water and stir at 35~60℃ for 0.5~2.0h to make a slurry, evaporate to dryness, crush and mix, and then place in flowing air and calcine at 300~400℃ for 1.0~2.0h, 500~600℃ for 2.0~3.0h and 700~800℃ for 3.0~5.0h to obtain the powder of the supported main catalyst; S2: Add the modifying agent G, pore-forming agent, and binder to the supported main catalyst powder obtained in step S1, mix evenly, and then form granules by spray drying, extrusion molding, or sheet forming. The granules are then calcined in flowing air at 300-400℃ for 1.0-2.0h and 500-550℃ for 3.0-5.0h to obtain the catalyst. x (Ca 1.0 A a B b O c )- y G / z Z particles.

9. The method according to claim 1, characterized in that, a >0, b ≥0, z >0; the catalyst x (Ca 1.0 A a B b O c )- y G / z Z is prepared through the following steps: S1: The carrier Z is impregnated with an equal volume of nitrate aqueous solution of B and / or A selected from non-alkaline earth metal elements at 35~60℃, evaporated to dryness, pulverized and mixed, and placed in flowing air for calcination at 300~400℃ for 1.0~2.0h, 500~600℃ for 2.0~3.0h and 700~800℃ for 3.0~5.0h to obtain a carrier powder loaded with auxiliary oxides; S2: Add Ca(OH)2 or a mixture of Ca(OH)2 and a hydroxide selected from alkaline earth metal element A to the carrier powder of the supported oxide promoter obtained in step S1, add water and stir for 0.5~2.0h to form a slurry and keep the slurry at 35~60℃, evaporate to dryness, crush and mix evenly, place in flowing air and calcine at 300~400℃ for 1.0~2.0h, 500~600℃ for 2.0~3.0h and 700~800℃ for 3.0~5.0h to obtain the powder of the supported main catalyst; S3: Add the modifying agent G, pore-forming agent, and binder to the supported main catalyst powder obtained in step S2, mix evenly, and then form granules by spray drying, extrusion, or flaking. The granules are then calcined in flowing air at 300-400℃ for 1.0-2.0h and 500-550℃ for 3.0-5.0h to obtain the catalyst. x (Ca 1.0 A a B b O c )- y G / z Z particles.

10. Catalyst x (Ca 1.0 A a B b O c )- y G / z The application of Z in the catalytic deethanolination of ethylene glycol dialkyl ethers to prepare vinylalkyl ethers is characterized by, In the catalyst, Ca 1.0 A a B b O c The catalyst is denoted as Z, and the support is denoted as Z. A is at least one element selected from Mg, Sr, Ba, Ga, In, Ge, and Sn; B is at least one element selected from rare earth metals; O is oxygen; G is a modifying agent selected from at least one substance selected from elemental Si, BN, AlN, GaN, C3N4, Si3N4, SiC, or Fe3C; Z contains at least one substance selected from SiO2, Al2O3, TiO2, ZrO2, all-silica molecular sieves, and metal ion-exchange molecular sieves. In the main catalyst, 1.0 , a、b and c These represent the molar ratios of Ca, A, B, and O in the main catalyst, respectively. a = 0~5.0、 b = 0~0.5; x, y and z These represent the mass fractions of the main catalyst, modifying agent, and support in the catalyst, respectively. x =30~98%, y = 2~25%, z =0~68%.

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