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CN-122006757-A - Catalyst for preparing alkyl vinyl ether by dehydrating hydrocarbyloxy ethanol and application thereof

CN122006757ACN 122006757 ACN122006757 ACN 122006757ACN-122006757-A

Abstract

The invention discloses a catalyst for preparing alkyl vinyl ether by dehydrating hydrocarbyloxy ethanol and application thereof. The chemical structural formula of the catalyst is x [ A a M b (PO 4 ) c ] -yG/zZ, wherein A a M b (PO 4 ) c is a main catalyst, A is at least one element selected from alkali metal and alkaline earth metal, M is at least one element selected from H, B, al, ga, in and Fe, G is an oxide of at least one element selected from rare earth metal, Z is a carrier and consists of Z-1 and/or Z-2, the carrier Z-1 is a porous material with a high specific surface area, and the carrier Z-2 is a heat-resistant material with high heat conductivity. The phosphate catalyst provided by the invention has the advantages of simple preparation process and low preparation cost, and particularly has excellent catalytic performance of the supported phosphate for preparing the alkyl vinyl ether by dehydrating the alkoxy ethanol.

Inventors

  • ZHANG CHUNLEI
  • TAO HUIQIN
  • CHEN CHENJU
  • WEI CHAO
  • ZHANG SHIHAN

Assignees

  • 上海师范大学
  • 上海师渝元科技有限公司

Dates

Publication Date
20260512
Application Date
20251208

Claims (10)

  1. 1. The catalyst for preparing the alkyl vinyl ether by dehydrating the hydrocarbyloxyethanol is characterized in that the chemical structural formula of the catalyst is x [ A a M b (PO 4 ) c ] -yG/zZ, wherein A a M b (PO 4 ) c is a main catalyst, A is at least one element selected from alkali metals and alkaline earth metals, M is at least one element selected from H, B, al, ga, in and Fe, G is at least one element selected from rare earth metals, Z is a carrier and consists of Z-1 and/or Z-2, the carrier Z-1 is a porous material with high specific surface area, the carrier Z-2 is a heat-resistant material with high heat conductivity, a, b and c respectively represent A, M and (the mol ratio of PO 4 ) 3- in the main catalyst, x, y and Z are mass fractions of the main catalyst, an auxiliary agent and the carrier respectively, a=1.0-3.0, b=0-2.0, c=1.0-2.0, x=1-50%, y=0-25%, and z=50-99.
  2. 2. The catalyst of claim 1, wherein A is at least one element selected from Li, na, K, cs, mg, ca, sr and Ba, M is at least one element selected from H, al, ga, in and Fe, G is an oxide of at least one element selected from Sc, Y, la, ce, nd, sm and Th, Z-1 is a porous material with a specific surface area of more than 50M 2 /G, at least one selected from SiO 2 、Al 2 O 3 、TiO 2 、ZrO 2 , clay and molecular sieve, Z-2 is a heat-resistant material with a heat conductivity of more than 5W/(m.K), at least one selected from Si element 、α-SiO 2 、α-Al 2 O 3 、BeO、MgO、SiC、BN、C 3 N 4 、AlN、Si 3 N 4 、MoS 2 and WS 2 , a = 1.0-3.0, b = 0-2.0 and c = 1.0-2.0, x = 3-30%, y = 0-20% and Z = 70-97%.
  3. 3. The catalyst of claim 1, wherein the hydrocarbyloxy is selected from the group consisting of C 1 ~C 10 alkoxy, C 1 ~C 10 haloalkoxy, C 2 ~C 6 hydroxyalkoxy, C 3 ~C 8 alkenylalkoxy, C 3 ~C 6 alkynyloxy, C 6 ~C 10 aralkoxy, C 3 ~C 10 heterocycloalkoxy, C 2 ~C 6 alkenyloxy, C 6 ~C 10 aryloxy, C 6 ~C 8 haloaryloxy, and C 6 ~C 8 hydroxyaryloxy.
  4. 4. A method for preparing the catalyst according to any one of claims 1 to 3, characterized in that the method comprises a step S1 of carrier powder preparation, a step S2 of catalyst powder preparation and a step S3 of catalyst particle preparation.
  5. 5. The method according to claim 4, wherein the step S1 is selected from one of the following (1) - (3): (1) The carrier Z comprises SiO 2 , and the step S1 is that 8-12% (v/v) tetraethyl orthosilicate is added into a 0.8-1.2 mol/L hydrochloric acid aqueous solution with the temperature of 55-65 ℃ and continuously stirred for 7-9 hours to obtain wet gel, and the wet gel is subjected to suction filtration, deionized water washing, 110-130 ℃ drying, roasting for 3-5 hours with the temperature of 450-550 ℃ in air flow, and ball milling to obtain SiO 2 carrier powder; (2) The carrier Z comprises a mesoporous molecular sieve, and the step S1 is that mesoporous molecular sieve powder is placed in air flow and roasted for 1-3 hours at 300-400 ℃ and 3-5 hours at 500-600 ℃ to obtain mesoporous molecular sieve carrier powder; (3) The carrier Z comprises a silicon-aluminum molecular sieve, and the step S1 is that silicon-aluminum molecular sieve powder is roasted for 1-3 hours at 300-400 ℃ and 3-5 hours at 500-600 ℃ in air flow, is ion-exchanged for 2-4 hours at 70-80 ℃ by using 0.8-1.2 mol/L NH 4 Cl aqueous solution for 3 times, and is roasted for 0.5-1.5 hours at 500-600 ℃ and 2-4 hours in air flow after being sequentially subjected to suction filtration, softened water washing and drying at 130-150 ℃ for 1-3 hours, so as to obtain the silicon-aluminum molecular sieve carrier powder; And step S3, adding pore-forming agent and binder into the catalyst powder prepared in step S2, uniformly mixing, tabletting and forming into particles, and roasting at a constant temperature of 550-650 ℃ in air flow for 4-6 hours to prepare the catalyst x [ A a M b (PO 4 ) c ] -yG/zZ particles.
  6. 6. The method according to claim 4 or 5, wherein the step S2 is selected from one of the following (1) to (4): (1) b=0 and y=0, wherein in the step S2, the phosphate solution of A is prepared, the phosphate solution is added into the carrier powder prepared in the step S1 according to the metering ratio, stirred for 2-4 hours, evaporated to dryness, crushed, and then baked for 0.5-1.5 hours at 300-400 ℃ and baked for 1-3 hours at 500-600 ℃ and baked for 4-6 hours at 700-800 ℃ in air flow to prepare catalyst powder; (2) b >0, y=0, wherein in the step S2, a phosphoric acid solution, a phosphate solution of A and a nitrate solution of M are respectively prepared, the phosphoric acid solution and the phosphate solution of A are added into the carrier powder prepared in the step S1 according to the metering ratio under stirring, the mixture is stirred for 0.5-1.5 h, then the nitrate solution of M is added, the temperature is kept at 50-70 ℃ for continuously stirring for 2-4 h, then the mixture is evaporated and crushed, and the mixture is roasted for 0.5-1.5 h at 300-400 ℃ and for 1-3 h at 500-600 ℃ and for 4-6 h at 700-800 ℃ in air flow to prepare catalyst powder; (3) b=0, y >0, wherein in the step S2, a phosphate solution of A is prepared, the phosphate solution is added into the carrier powder prepared in the step S1 according to a metering ratio, after stirring for 2-4 hours, a nitrate solution of a rare earth metal element in G is added, stirring is continued for 1-2 hours, then the mixture is evaporated to dryness and crushed, and then the mixture is roasted for 0.5-1.5 hours at 300-400 ℃ and for 1-3 hours at 500-600 ℃ and for 4-6 hours at 700-800 ℃ in air flow, so that catalyst powder is prepared; (4) b >0, y >0, wherein the step S2 is to prepare a phosphoric acid solution, a phosphate solution of A and a nitrate solution of M respectively, add the phosphoric acid solution and the phosphate solution of A into the carrier powder prepared in the step S1 according to the metering ratio under stirring, continuously stir for 0.5-1.5 h, then add the nitrate solution of M, keep the temperature at 50-70 ℃ and continuously stir for 2-4 h, then add the nitrate solution of rare earth metal element in the step G, continuously stir for 1-3 h, evaporate and pulverize, then bake for 0.5-1.5 h, bake for 1-3 h and bake for 4-6 h at 500-600 ℃ in air flow at 300-400 ℃ to prepare the catalyst powder.
  7. 7. The method according to claim 4 or 5, wherein in the step S3, the pore-forming agent is at least one of water, nitric acid, acetic acid, citric acid, sorbic acid, terephthalic acid, stearic acid, ethylene glycol, 1, 4-butanediol, glycerol and vegetable oil, the addition amount is 4-10wt% of the catalyst powder, the binder is at least one of sesbania powder, cellulose, methylcellulose, lignin, polyethylene glycol (PEG), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP) and starch, and the addition amount is 5-15wt% of the catalyst powder.
  8. 8. The use of the catalyst according to any one of claims 1-3 in a reaction for preparing alkyl vinyl ether by catalyzing dehydration of hydrocarbyloxy ethanol, wherein the reaction is a fixed bed reactor, a fluidized bed reactor or a moving bed reactor, the feeding of the reactor comprises diluent gas, and the reaction conditions are that the reaction temperature is 350-500 ℃, the system pressure is 0.01-1.00 MPa, the hydrocarbyloxy ethanol liquid hourly weight space velocity is 0.05-5.00 h -1 and the diluent gas hourly space velocity is 0-3000 h -1 .
  9. 9. The use of claim 8, wherein the diluent gas is at least one of an N 2 、CO 2 、N 2 -CO 2 mixture, an H 2 、N 2 -H 2 mixture, oxygen-depleted air, oxygen-containing N 2 , oxygen-containing CO 2 , or industrial tail gas.
  10. 10. A process for preparing a hydrocarbyl vinyl ether, characterized in that the process comprises preparing a hydrocarbyl vinyl ether by catalytic dehydration of hydrocarbyloxyethanol using the catalyst according to any one of claims 1-3.

Description

Catalyst for preparing alkyl vinyl ether by dehydrating hydrocarbyloxy ethanol and application thereof Technical Field The invention belongs to the technical field of chemical catalysts, and particularly relates to a catalyst for preparing hydrocarbon vinyl ether by dehydrating hydrocarbyloxy ethanol and application thereof. Background Hydrocarbyloxyethanol is also known as ethylene glycol monoalkyl ether or hydrocarbyloxyethyl ether and includes methoxy, ethoxy, butoxy, cyclohexyloxy, phenoxy, benzyloxy, hydroxyethoxy, hydroxyethoxyethoxyethanol, and the like. Alkyl vinyl ethers, also known as vinyl alkyl ethers or hydrocarbyloxyethylene, are commonly known as methyl, ethyl, butyl, trifluoromethyl, heptafluoropropyl, 2-hydroxyethyl, 2-hydroxyethoxyethyl, 2-ethyleneoxyethyl, 4-hydroxybutyl, vinyl, allyl, phenyl, benzyl or furanmethyl vinyl ethers, and the like. Vinyl ethers are widely used in various industrial fields, and can be used for synthetic resins, adhesives, glutaraldehyde and the like. The vinyl ether compound has wide application prospect and has important significance in developing vinyl ether series products in China. At present, the method for producing the alkyl vinyl ether at home and abroad mainly adopts an acetylene addition method and an acetal pyrolysis method. For the vinyl ether preparation route by the acetylene addition method, the search for efficient solid catalysts and improvement of the reaction process have been focused on. The catalyst is from the alkali metal hydroxide solution adopted initially, to the alcohol solution of alkali metal alkoxide, to the solvent-assisted super-alkali system and finally to the supported solid catalyst. The most obvious defects of the acetylene addition method are that the liquid strong alkali catalyst is used, the dosage is large, the catalyst is easy to inactivate and has serious environmental pollution, the high reaction temperature and the high reaction pressure lead the raw material acetylene to have explosion risk, the danger is high, the requirement on production equipment is high, and the single-series reaction device is difficult to be large. The acetal gas phase cracking method is mainly focused on the research of catalysts, and is developed into a Lewis acid catalyst with relatively low price from a noble metal catalyst used in early stage, and a phosphate catalyst is mainly adopted at present, but the reaction temperature is high, the product is complex, the acetal is easy to form peroxide at high temperature, and the explosion risk exists. Therefore, there is a need to develop new process routes for synthesizing vinyl ethers. Recently, large-scale industrialized coal-based ethylene glycol is used as a starting material, ethylene glycol monoether obtained through etherification reaction with alcohols is subjected to gas-phase catalytic dehydration to prepare vinyl ether, and the ethylene glycol serving as the starting material is cheap and easy to obtain, and the process is green and safe, so that the method has attractive force. Patent JP3685942B discloses the preparation of ethyl vinyl ether by vapor phase dehydration of ethylene glycol monoethyl ether (ethoxyethanol) with the aid of a Cs 2O/SiO2 catalyst. Ethylene glycol monoethyl ether conversion was 72.5% and ethyl vinyl ether selectivity was 84.4% at a reaction temperature of 420 ℃ and a volume space velocity of 1500h -1. However, cs 2O/SiO2 catalysts are relatively expensive and Cs species are gradually lost over time, resulting in catalyst deactivation. Therefore, there is a need to develop a safer, more efficient, more stable, more economical or more environmentally friendly catalyst for the preparation of alkyl vinyl ethers by dehydration of hydrocarbyloxyethanol. Disclosure of Invention In order to make up the defects of the prior art, the invention provides a catalyst for preparing alkyl vinyl ether by dehydrating hydrocarbyloxy ethanol, which is simple and convenient to prepare and relatively low in cost, and aims to realize safe, effective, economical, environment-friendly and high-selectivity vinyl ether preparation of target products. In one aspect, the invention provides a catalyst for preparing alkyl vinyl ether by dehydrating alkoxy ethanol, which has a chemical structural formula of x [ A aMb(PO4)c ] -yG/zZ, wherein A aMb(PO4)c is a main catalyst, A is at least one element selected from alkali metals and alkaline earth metals, M is at least one element selected from H, B, al, ga, in and Fe, G is at least one element oxide selected from rare earth metals, Z is a carrier and consists of Z-1 and/or Z-2, the carrier Z-1 is a porous material with a high specific surface area, the carrier Z-2 is a heat-resistant material with high heat conductivity, a, b and c respectively represent the mole ratio of A, M and PO 4)3- in the main catalyst, x, y and Z are mass fractions of the main catalyst, an auxiliary agent and the carrier, a=1.0 to 3.0, b=0 to 2.0, c=x=1 to 50%, y=0 to