Etherification catalyst as well as preparation method and application thereof

Abstract

The invention relates to the technical field of resin catalyst synthesis and discloses an etherification catalyst as well as a preparation method and application thereof. The method comprises the following steps: (1) in the presence of a pore-foaming agent, a dispersing agent and an initiator, sequentially carrying out a first-stage polymerization reaction and a second-stage polymerization reaction on a polymeric monomer to obtain macroporous white balls; (2) soaking the macroporous white balls in halogenated alkane for swelling, then carrying out a first-stage sulfonation reaction on a first sulfonating agent and the swelled material, then removing the halogenated alkane in the reacted material, and carrying out a second-stage sulfonation reaction on the material without the halogenated alkane and a second sulfonating agent; the polymeric monomers are halogenated styrene and vinylbenzene. According to the etherification catalyst, polymerization monomers in polymerization reaction are changed, so that the prepared etherification catalyst has higher thermal stability and excellent mechanical strength, active components are not prone to loss, and the etherification catalyst can be used for catalyzing C8 tertiary carbon olefin etherification reaction and has excellent catalytic activity and long-acting stability.

Description

Technical Field

[0001] This invention relates to the field of resin catalyst synthesis technology, specifically to an etherification catalyst, its preparation method, and its application. Background Technology

[0002] Coal liquefaction technology, especially indirect coal liquefaction technology, is mature. Its core reaction is the Fischer-Tropsch reaction. The reaction products are widely distributed (C1-C100) and basically follow the ASF (Anderson-Schulz-Flory) rule. However, the product composition is complex, mainly including α-olefins, n-alkanes, and oxygen-containing compounds such as alcohols, ketones, aldehydes, esters, and acids. The α-olefin content is 40-50%, and the oxide content is 2-5%.

[0003] Polymerized materials (POE) from octene and ethylene monomers possess advantages such as impact resistance, tear resistance, melt stability, good sealing performance, and optical properties. However, there is currently no industrial-scale 1-octene production facility, and the availability of 1-octene as a raw material severely restricts POE production, hindering the upgrading of domestic materials. Currently, the main 1-octene production technologies include paraffin cracking, ethylene oligomerization, and the SASOL Fischer-Tropsch product separation method. Paraffin cracking and ethylene oligomerization involve reactions and separations, resulting in complex processes, high costs, and low purity and yield of 1-octene. The SASOL Fischer-Tropsch product separation method, which separates 1-octene from Fischer-Tropsch synthetic oil products, has a shorter process and lower costs, but the technology is strictly confidential.

[0004] In the Fischer-Tropsch separation of high-purity 1-octene, the presence of near-boiling C8 tertiary olefins makes it impossible to obtain high-purity 1-octene using conventional distillation techniques. C8 tertiary olefins have the property of etherifying with lower alcohols to form high-boiling ethers. Therefore, separating the near-boiling C8 tertiary olefins from 1-octene is transformed into separating high-boiling ethers, reducing the separation difficulty. In the Fischer-Tropsch C8 tertiary olefin etherification process, the increased carbon chain number of C8 tertiary olefins leads to different reaction patterns compared to the currently mature C4 / C5 tertiary olefin etherification. This places higher demands on resin etherification catalysts, requiring higher reaction temperatures, stronger mechanical strength, higher reaction conversion rates, and lower isomerization side reactions. Currently, etherification catalysts for C4 tertiary olefins, C5 tertiary olefins, and gasoline component tertiary olefins suffer from several problems, including insufficient thermal stability, making them unsuitable for higher reaction temperatures; insufficient mechanical strength, leading to easy breakage and pulverization due to material impact; and the gradual loss of sulfonic acid groups as the reaction proceeds, resulting in decreased reactivity and reduced catalyst lifespan.

[0005] Chinese patent CN 1238111C discloses a high-exchange-capacity resin catalyst, which is polymerized from styrene and divinylbenzene using straight-chain alkanes and benzene derivatives as porogens. Its characteristics include interconnected macropores via micropores, resulting in a large specific surface area and high exchange capacity. However, it suffers from insufficient mechanical strength and is easily broken. While suitable for the etherification of low-carbon tertiary olefins such as isobutylene, it is not applicable to the etherification of C8 high-carbon tertiary olefins. Chinese patent CN 102688774B discloses a gasoline etherification resin catalyst. By introducing trifluoromethylimidazolium hydrogen sulfate ionic liquid into a macroporous cation exchange resin, the catalyst exhibits excellent low-temperature reactivity and selectivity, but it cannot be applied to high-temperature, high-carbon-number etherification reactions. Chinese patent CN 106552669B discloses a large-particle resin catalyst, prepared by sulfonation after suspension copolymerization of styrene, polyethylene, and monomers. However, it is only applicable to the hydration, etherification, and condensation reactions of low-carbon C4 tertiary olefins, and is not suitable for high-carbon tertiary olefins. Therefore, commercially available resin etherification catalysts cannot meet the requirements for the etherification of C8 tertiary olefins. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems of existing resin etherification catalysts being unable to be used for catalyzing the etherification reaction of high-carbon tertiary olefins, and to provide an etherification catalyst, its preparation method, and its application. This etherification catalyst, by changing the polymerizing monomer in the polymerization reaction, enables the prepared etherification catalyst to have higher thermal stability and excellent mechanical strength, and the active components are not easily lost, making it suitable for catalyzing the etherification reaction of C8 tertiary olefins, and exhibiting excellent catalytic activity and long-term stability.

[0007] To achieve the above objectives, the present invention provides a method for preparing an etherification catalyst, the method comprising the following steps:

[0008] (1) In the presence of a pore-forming agent, a dispersant and an initiator, the polymer monomers are subjected to a first-stage polymerization reaction and a second-stage polymerization reaction in sequence to obtain macroporous white spheres;

[0009] (2) The macroporous white spheres are immersed in haloalkanes for swelling, then the first sulfonating agent is used to carry out a first-stage sulfonation reaction with the swollen material, then the haloalkanes in the reacted material are removed, and the material after removing the haloalkanes is used to carry out a second-stage sulfonation reaction with the second sulfonating agent.

[0010] The polymerization monomer is a combination of halostyrene and vinylbenzene, wherein the halostyrene is fluorostyrene and / or chlorostyrene, and the temperature of the second-stage polymerization reaction is 5-80°C higher than the temperature of the first-stage polymerization reaction.

[0011] Preferably, in the polymeric monomer, the content of the halostyrene is 0.2-0.7 wt%, and the content of the vinylbenzene is 0.3-0.8 wt%.

[0012] Preferably, relative to 100 parts by weight of the polymerizing monomer, the amount of the initiator is 5-10 parts by weight, the amount of the porogen is 50-200 parts by weight, and the amount of the dispersant is 20-50 parts by weight.

[0013] Preferably, the conditions for the first-stage polymerization reaction include: a temperature of 30-180℃ and a time of 1-12h.

[0014] Preferably, the conditions for the two-stage polymerization reaction include: a temperature of 40-200℃ and a time of 1-12h.

[0015] Preferably, the conditions for the first-stage sulfonation reaction include: a temperature of 60-140°C and a time of 8-24 hours.

[0016] Preferably, the conditions for the two-stage sulfonation reaction include: a temperature of 60-140°C and a time of 8-24 hours.

[0017] Preferably, the ratio of the total weight of the first sulfonating agent and the second sulfonating agent, the weight of the macroporous white spheres, and the weight of the haloalkane is 1-6:1:2-5.

[0018] Preferably, the weight ratio of the first sulfonating agent to the second sulfonating agent is 1:0.9-1.2.

[0019] Preferably, the dispersant is selected from at least one of polyvinyl alcohol, gelatin, saponified styrene-maleic anhydride copolymer, hydroxypropyl methylcellulose, and polyacrylamide.

[0020] Preferably, the pore-forming agent is selected from at least one of n-hexane, benzene, toluene, xylene, and liquid paraffin.

[0021] Preferably, the initiator is selected from N,N-dimethylformamide and / or benzoyl peroxide.

[0022] Preferably, the haloalkane is selected from at least one of monochloroethane, dichloroethane, and tetrachloroethane.

[0023] Preferably, the first sulfonating agent and the second sulfonating agent are each selected from at least one of concentrated sulfuric acid, chlorosulfonic acid, fluorosulfonic acid and fuming sulfuric acid.

[0024] A second aspect of the present invention provides an etherification catalyst prepared by the above method.

[0025] A third aspect of the present invention provides the application of the etherification catalyst described above in the catalytic etherification reaction of C8 tertiary olefins with lower alcohols.

[0026] The method described in this invention, through the polymerization reaction of halostyrene and vinylbenzene, enables the preparation of an etherification catalyst with excellent mechanical strength and thermal stability, thus ensuring that the etherification catalyst can withstand high reaction temperatures. Furthermore, in this method, macroporous white spheres are first swollen in a haloalkanes, and then the swollen material is sulfonated. This allows for a tighter bond between the active component (sulfonic acid groups) and the matrix, while increasing the content of the active component in the catalyst, preventing the loss of the reactive component, and ensuring a longer service life for the etherification catalyst. Moreover, the etherification catalyst described in this invention can achieve a catalytic efficiency of over 90% when used in the etherification reaction of C8 tertiary olefins, exhibiting high catalytic activity and good stability, and thus possessing a wider range of applications. Detailed Implementation

[0027] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0028] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0029] The preparation method of the etherification catalyst of the present invention includes the following steps:

[0030] (1) In the presence of a pore-forming agent, a dispersant and an initiator, the polymer monomers are subjected to a first-stage polymerization reaction and a second-stage polymerization reaction in sequence to obtain macroporous white spheres;

[0031] (2) The macroporous white spheres are immersed in haloalkanes for swelling, then the first sulfonating agent is used to carry out a first-stage sulfonation reaction with the swollen material, the haloalkanes in the reacted material are removed, and the material after removing the haloalkanes is used to carry out a second-stage sulfonation reaction with the second sulfonating agent.

[0032] In the method described in this invention, the polymerizing monomer is a combination of halostyrene and vinylbenzene. By using halostyrene, which has greater rigidity, as the polymerizing monomer to polymerize with vinylbenzene monomer, macroporous white spheres are prepared. This significantly improves the mechanical strength and thermal stability of the macroporous white spheres, making them less prone to breakage and pulverization. This ensures that the prepared etherification catalyst has superior mechanical properties, can withstand higher reaction temperatures, and is more suitable for catalyzing the etherification reaction of C8 tertiary olefins.

[0033] Specifically, the halostyrene can be a dihalogenated styrene and / or a monohalogenated styrene, more preferably a monohalogenated styrene. In some preferred cases, the halogen atom contained in the halostyrene can be Cl and / or Br, more preferably Cl.

[0034] In some particularly preferred cases, the halogenated styrene is selected from at least one of o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, 2,3-dichlorostyrene, 2,4-dichlorostyrene, 2,5-dichlorostyrene, 2,6-dichlorostyrene, 3,4-dichlorostyrene, 3,5-dichlorostyrene, o-fluorostyrene, m-fluorostyrene, p-fluorostyrene, 2,3-difluorostyrene, 2,4-difluorostyrene, 2,5-difluorostyrene, 2,6-difluorostyrene, 3,4-difluorostyrene, and 3,5-difluorostyrene, preferably at least one of o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, 2,3-dichlorostyrene, 2,4-dichlorostyrene, 2,5-dichlorostyrene, 2,6-dichlorostyrene, 3,4-dichlorostyrene, and 3,5-dichlorostyrene, further preferably at least one of o-chlorostyrene, m-chlorostyrene, and p-chlorostyrene, and more preferably p-chlorostyrene.

[0035] In the method described in this invention, the porogen is used to first create space between the polymer chains, and then the porogen is extracted upon completion of polymerization to form a porous structure. The method described in this invention does not limit the specific composition of the porogen used. In some preferred embodiments, the porogen is selected from at least one of n-hexane, benzene, toluene, xylene, and liquid paraffin, more preferably liquid paraffin.

[0036] In the method described in this invention, the dispersant is used to prevent droplets from merging into larger droplets upon collision, control droplet size, and improve the dispersibility of the catalyst support. This invention does not limit the specific composition of the dispersant used. In some embodiments, the dispersant is selected from at least one of polyvinyl alcohol, gelatin, saponified styrene-maleic anhydride copolymer, hydroxypropyl methylcellulose, and polyacrylamide, preferably a combination of polyvinyl alcohol, gelatin, and saponified styrene-maleic anhydride copolymer. Specifically, the weight-average molecular weight of the polyvinyl alcohol used in this invention can be 10,000–30,000 g / mol.

[0037] In the method described in this invention, the initiator is used to initiate the polymerization reaction of the halostyrene and vinylbenzene, and the initiator is selected from N,N-dimethylformamide and / or benzoyl peroxide, preferably benzoyl peroxide.

[0038] In some preferred embodiments, in order to further improve the mechanical strength and thermal stability of the prepared etherification catalyst, the content of the halostyrene in the polymer monomer is 0.2-0.7 wt%, preferably 0.3-0.6 wt%, and the content of the vinylbenzene is 0.3-0.8 wt%, preferably 0.4-0.7 wt%.

[0039] In some preferred embodiments, the amount of the initiator is 5-10 parts by weight, preferably 7-8 parts by weight, relative to 100 parts by weight of the polymerizing monomer; the amount of the porogen is 50-200 parts by weight, preferably 100-150 parts by weight; and the amount of the dispersant is 20-50 parts by weight, preferably 30-40 parts by weight.

[0040] In the method described in this invention, to improve the rigidity of the prepared macroporous white spheres, thereby further improving the thermal stability and mechanical strength of the prepared etherification catalyst, the halostyrene and vinylbenzene are subjected to a one-stage polymerization reaction and a two-stage polymerization reaction sequentially. Simultaneously, the temperature of the two-stage polymerization reaction is further limited to be 5-80°C higher than the temperature of the one-stage polymerization reaction, preferably 6-30°C, and more preferably 10-25°C. Specifically, the temperature of the two-stage polymerization reaction is 5°C, 8°C, 10°C, 12°C, 15°C, 18°C, 20°C, 22°C, 24°C, 26°C, 28°C, or 30°C higher than the temperature of the one-stage polymerization reaction.

[0041] In some preferred embodiments, the conditions for the first-stage polymerization reaction include: a temperature of 30-180℃, preferably 40-120℃, more preferably 45-100℃, and a time of 1-12 hours; the conditions for the second-stage polymerization reaction include: a temperature of 40-200℃, preferably 50-150℃, more preferably 55-100℃, and a time of 1-12 hours. By controlling the temperature and time of the first-stage and second-stage polymerization reactions, the polymerization raw materials and reaction conditions can be matched, thereby enabling the prepared etherification catalyst to possess superior thermal stability and mechanical strength, ensuring that the etherification catalyst can be better applied to the etherification reaction of C8 tertiary carbon olefins. Specifically, the temperature of the first-stage polymerization reaction can be 50℃, 60℃, 65℃, 70℃, 75℃, or 80℃, and the time of the first-stage polymerization reaction can be 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, or 12 hours. The temperature of the two-stage polymerization reaction can be 50℃, 60℃, 65℃, 70℃, 75℃, 80℃, 85℃, 90℃, 95℃ or 100℃, and the time of the two-stage polymerization reaction can be 6h, 7h, 8h, 9h, 10h, 11h or 12h.

[0042] In some embodiments, the first-stage polymerization reaction and the second-stage polymerization reaction are accompanied by stirring, and the stirring speed is 150-250 rad / min, preferably 170-220 rad / min.

[0043] In some embodiments, the specific operation process of step (1) includes: mixing dispersant, porogen, initiator, halostyrene and vinylbenzene, then carrying out a first-stage polymerization reaction and a second-stage polymerization reaction in sequence, filtering after the reaction, then extracting the porogen in the solid material after the reaction with petroleum ether, and then sieving to obtain macroporous white spheres with a diameter of 0.3mm-0.8mm.

[0044] In the method described in this invention, the macroporous white spheres prepared in step (1) are first impregnated in haloalkanes. The macroporous white spheres swell in the haloalkanes, which facilitates the loosening of the entangled polymer chains and is more conducive to the subsequent sulfonation reaction between the sulfonating agent and the styrene in the macroporous white spheres. This increases the loading of the active component sulfonic acid groups in the prepared etherified catalyst, and further increases the content of the active component in the etherified catalyst through a two-step sulfonation reaction. It can also further strengthen the binding strength between the active component sulfonic acid groups and the polymer, improve the catalytic activity of the prepared etherified catalyst, and ensure the stability of the active component content, so that the active component of the catalyst is not easily lost. This further ensures the long-term stability of the catalytic activity of the prepared etherified catalyst and extends the service life of the catalyst.

[0045] In some preferred embodiments, in order to further ensure the long-term stability of the catalytic performance of the prepared etherified catalyst, the haloalkane is further limited to at least one selected from monochloroethane, dichloroethane and tetrachloroethane, preferably dichloroethane.

[0046] In some preferred embodiments, the first sulfonating agent and the second sulfonating agent are each selected from at least one of concentrated sulfuric acid, chlorosulfonic acid, fluorosulfonic acid, and fuming sulfuric acid, preferably concentrated sulfuric acid and fuming sulfuric acid. Specifically, in this invention, the concentrated sulfuric acid refers to an aqueous solution of sulfuric acid with a sulfuric acid concentration ≥70wt%, and the fuming sulfuric acid refers to a sulfuric acid solution of sulfur trioxide.

[0047] In some preferred embodiments, the ratio of the total weight of the first sulfonating agent and the second sulfonating agent, the weight of the macroporous white spheres, and the weight of the haloalkane is 1-6:1:2-5, preferably 2-5:1:2.5-4, and more preferably 2.5-4:1:2.5-4.

[0048] In some preferred embodiments, the weight ratio of the first sulfonating agent to the second sulfonating agent is further limited to 1:0.9-1.2, more preferably 1:0.95-1.1, and particularly preferably 1:0.98-1.05. By further limiting the ratio of the first sulfonating agent to the second sulfonating agent, the degree of sulfonation of the macroporous white spheres in the sulfonation reaction can be guaranteed, and the content of the active component in the prepared etherification catalyst can be further increased, thereby further improving the catalytic activity and stability of the catalytic performance of the etherification catalyst.

[0049] In some preferred embodiments, the conditions for the first-stage sulfonation reaction include: a temperature of 60-140°C, preferably 80-100°C, and a time of 8-24 hours. The conditions for the second-stage sulfonation reaction include: a temperature of 60-140°C, preferably 100-120°C, and a time of 8-24 hours.

[0050] In a further preferred embodiment, the temperature of the first-stage sulfonation reaction is lower than the temperature of the second-stage sulfonation reaction. In a particularly preferred case, the temperature of the first-stage sulfonation reaction is 5-30°C lower than the temperature of the second-stage sulfonation reaction.

[0051] The etherification catalyst prepared by the method described in this invention possesses excellent mechanical strength and high-temperature resistance. Furthermore, the etherification catalyst has a higher content of sulfonic acid groups as its active component, and the bonding force between the active component and the polymer matrix is ​​stronger, ensuring that the active component is not easily lost and thus guaranteeing a longer catalyst lifespan. The etherification catalyst of this invention achieves a catalytic efficiency of over 90% in the etherification reaction of C8 tertiary olefins with lower alcohols, far exceeding that of commercially available catalysts. It exhibits excellent catalytic activity and can be effectively used for catalyzing the etherification reaction of C8 tertiary olefins with lower alcohols, especially the etherification reaction of C8 tertiary olefins with methanol. Specifically, when the etherification catalyst described in this invention is used to catalyze the etherification reaction of C8 tertiary olefins with lower alcohols, the reaction mechanism of the etherification reaction is a nucleophilic addition reaction. During the reaction, the raw materials are adsorbed on the surface of the etherification catalyst, and then the adsorbed raw materials react on the catalyst surface. The resulting product is desorbed from the catalyst surface and diffused into the solution. By using the etherification catalyst described in this invention, the etherification reaction of C8 tertiary olefins with methanol can be realized, thereby obtaining a high-purity 1-octene product.

[0052] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited thereto.

[0053] The polyvinyl alcohol used in the following examples has CAS number 9002-89-5, an average Mw of 13000-23000, and is 98% hydrolyzed. The saponified styrene-maleic anhydride copolymer used was purchased from Jiaxing Huawen Chemical Co., Ltd., and its product brand is D-20.

[0054] Example 1

[0055] In a stainless steel stirred tank equipped with a reflux condenser, 4500g of 10% sodium chloride aqueous solution, 13.5g of polyvinyl alcohol, 135g of gelatin, and 67.5g of saponified styrene-maleic anhydride copolymer were added and stirred at a speed of 200 rad / min to completely dissolve the dispersant in the reactor. Then, 375g of p-chlorostyrene, 375g of vinylbenzene, 750g of liquid paraffin, and 75g of benzoyl peroxide were added. The oil droplets were evenly dispersed and of appropriate size. The mixture was heated to 60℃ at a rate of 1℃ / min and reacted at a constant temperature for 2 hours. Then, the temperature was increased to 80℃ at a rate of 1℃ / min and reacted at a constant temperature for 2 hours. After the reaction was completed, the mixture was cooled and filtered, washed with hot water, dried, and then the pore-forming agent was extracted with petroleum ether. The macroporous white spheres with a diameter of 0.3-0.8mm were then sieved out.

[0056] In an enamel-lined reactor, 550g of macroporous white spheres were added to 1650g of dichloroethane and allowed to swell for 2 hours. Then, 1650g of concentrated sulfuric acid was added to the swollen material, and the temperature was raised to 100℃ at 1℃ / min and kept at a constant temperature for 4 hours under reflux. The dichloroethane was then distilled off. Next, 1650g of fuming sulfuric acid was added, and the temperature was raised to 104℃ at 1℃ / min and kept at a constant temperature for 8 hours. After the reaction was completed, the mixture was diluted stepwise with olefinic sulfuric acid and washed with deionized water until the effluent was neutral. The resulting solid phase was then dried to obtain the etherification catalyst C1.

[0057] Example 2

[0058] In a stainless steel stirred tank equipped with a reflux condenser, add 4500g of 10% sodium chloride aqueous solution, 13.5g of polyvinyl alcohol, 135g of gelatin, and 67.5g of saponified styrene-maleic anhydride copolymer and stir at 200 rad / min to completely dissolve the dispersant in the reactor. Add 375g of o-chlorostyrene, 375g of vinylbenzene, 750g of liquid paraffin, and 75g of benzoyl peroxide. The oil droplets are evenly dispersed and of appropriate size. Heat the mixture to 80℃ at 1℃ / min and react at a constant temperature for 1 hour. Then heat it to 100℃ at 1℃ / min and react at a constant temperature for 1 hour. After the reaction is completed, cool and filter, wash with hot water, dry, extract the pore-forming agent with petroleum ether, and then sieve out macroporous white spheres with a diameter of 0.3-0.8mm.

[0059] In an enamel-lined reactor, 500g of macroporous white spheres were added to 1500g of dichloroethane and allowed to swell for 2 hours. Then, 1500g of concentrated sulfuric acid was added to the swollen material, and the temperature was increased to 100℃ at 1℃ / min. The mixture was then refluxed for 4 hours to distill off the dichloroethane. Next, 1500g of fuming sulfuric acid was added, and the temperature was increased to 104℃ at 1℃ / min. The mixture was kept at this temperature for 8 hours. After the reaction was completed, the mixture was diluted stepwise with olefinic sulfuric acid and washed with deionized water until the effluent was neutral. The resulting solid phase was then dried to obtain the etherification catalyst C2.

[0060] Example 3

[0061] In a stainless steel stirred tank equipped with a reflux condenser, add 4500g of 10% sodium chloride aqueous solution, 13.5g of polyvinyl alcohol, 135g of gelatin, and 67.5g of saponified styrene-maleic anhydride copolymer and stir at 200 rad / min to completely dissolve the dispersant in the reactor. Then add 375g of m-chlorostyrene, 375g of vinylbenzene, 750g of liquid paraffin, and 75g of benzoyl peroxide. The oil droplets are evenly dispersed and of appropriate size. The mixture is heated to 50℃ at 1℃ / min and reacted at a constant temperature for 4 hours. Then the temperature is increased to 60℃ at 1℃ / min and reacted at a constant temperature for 4 hours. After cooling, filter, wash with hot water, dry, extract the pore-forming agent with petroleum ether, and then sieve out macroporous white spheres with a diameter of 0.3-0.8mm.

[0062] In an enamel-lined reactor, 450g of macroporous white spheres were added to 1350g of dichloroethane and allowed to swell for 2 hours. Then, 1350g of concentrated sulfuric acid was added to the swollen material, and the temperature was increased to 100℃ at 1℃ / min. The mixture was then refluxed for 4 hours to distill off the dichloroethane. Next, 1350g of fuming sulfuric acid was added, and the temperature was increased to 104℃ at 1℃ / min. The mixture was kept at a constant temperature for 8 hours. After the reaction was completed, the mixture was diluted stepwise with olefinic sulfuric acid and washed with deionized water until the effluent was neutral. The resulting solid phase was then dried to obtain the etherification catalyst C3.

[0063] Example 4

[0064] In a stainless steel stirred tank equipped with a reflux condenser, add 4500g of 10% sodium chloride aqueous solution, 13.5g of polyvinyl alcohol, 135g of gelatin, and 67.5g of saponified styrene-maleic anhydride copolymer and stir at 200 rad / min to completely dissolve the dispersants in the reactor. Add 375g of 2,4-dichlorostyrene, 375g of vinylbenzene, 750g of liquid paraffin, and 75g of benzoyl peroxide. The oil droplets are evenly dispersed and of appropriate size. Heat the mixture to 60℃ at 1℃ / min and react at a constant temperature for 2 hours. Then heat it to 80℃ at 1℃ / min and react at a constant temperature for 2 hours. After cooling, filter, wash with hot water, dry, extract the pore-forming agent with petroleum ether, and then sieve out macroporous white spheres with a diameter of 0.3-0.8mm.

[0065] In an enamel-lined reactor, 550g of macroporous white spheres were added to 1650g of dichloroethane and allowed to swell for 2 hours. Then, 1650g of concentrated sulfuric acid was added to the swollen material, and the temperature was increased to 100℃ at 1℃ / min. The mixture was then refluxed for 2 hours to distill off the dichloroethane. Next, 1650g of fuming sulfuric acid was added, and the temperature was increased to 104℃ at 1℃ / min. The mixture was kept at a constant temperature for 4 hours. After the reaction was completed, the mixture was diluted stepwise with olefinic sulfuric acid and washed with deionized water until the effluent was neutral. The resulting solid phase was then dried to obtain the etherification catalyst C4.

[0066] Example 5

[0067] In a stainless steel stirred tank equipped with a reflux condenser, add 4500g of 10% sodium chloride aqueous solution, 13.5g of polyvinyl alcohol, 135g of gelatin, and 67.5g of saponified styrene-maleic anhydride copolymer and stir at 200 rad / min to completely dissolve the dispersants in the reactor. Add 375g of m-fluorostyrene, 375g of vinylbenzene, 750g of liquid paraffin, and 75g of benzoyl peroxide. The oil droplets are evenly dispersed and of appropriate size. Heat the mixture to 60℃ at 1℃ / min and react at a constant temperature for 2 hours. Then heat it to 80℃ at 1℃ / min and react at a constant temperature for 2 hours. After cooling, filter, wash with hot water, dry, extract the pore-forming agent with petroleum ether, and then sieve out macroporous white spheres with a diameter of 0.3-0.8mm.

[0068] In an enamel-lined reactor, 550g of macroporous white spheres were added to 1650g of dichloroethane and allowed to swell for 2 hours. Then, 1650g of concentrated sulfuric acid was added to the swollen material, and the mixture was heated to 100°C at a rate of 1°C / min and refluxed for 4 hours to distill off the dichloroethane. Next, 1650g of fuming sulfuric acid was added, and the mixture was heated to 104°C at a rate of 1°C / min and reacted at a constant temperature for 8 hours. After the reaction was completed, the mixture was diluted stepwise with olefinic sulfuric acid and washed with deionized water until the effluent was neutral. The resulting solid phase was then dried to obtain the etherification catalyst C5.

[0069] Example 6

[0070] The method was carried out according to Example 1, except that the saponified styrene-maleic anhydride copolymer was replaced with polyvinyl alcohol for preparation.

[0071] Example 7

[0072] The method was carried out according to Example 1, except that 67.5g of saponified styrene-maleic anhydride copolymer was replaced with 33.75g of hydroxypropyl methylcellulose and 33.75g of polyacrylamide.

[0073] Comparative Example 1

[0074] The preparation was carried out according to the method of Example 1, except that p-chlorostyrene was replaced with an equal weight of styrene.

[0075] Comparative Example 2

[0076] The method of Example 1 was implemented, except that in step (1), the mixture was heated to 60°C at 1°C / min and reacted at a constant temperature for 4 hours. After the reaction was completed, it was cooled and filtered, washed with hot water, dried, and then the pore-forming agent was extracted with petroleum ether and then the macroporous white spheres were sieved out.

[0077] Comparative Example 3

[0078] The method of Example 1 was implemented, except that in step (1), the mixture was heated to 60°C at 1°C / min and reacted at a constant temperature for 2 hours, then heated to 63°C at 1°C / min and reacted at a constant temperature for 2 hours. After the reaction was completed, the mixture was cooled and filtered, washed with hot water, dried, and then the pore-forming agent was extracted with petroleum ether and the macroporous white spheres were sieved out.

[0079] Test case

[0080] Test Example 1

[0081] The etherification catalysts prepared in the examples and comparative examples were boiled at 190°C for 120 h, and the exchange capacity before and after boiling was tested. The test results are shown in Table 1.

[0082] Table 1

[0083]

[0084]

[0085] As can be seen from the results in Table 1, the etherification catalyst prepared by the method described in this invention has a higher exchange capacity and a lower exchange capacity reduction rate after cooking at 190°C for 120 h, indicating that the etherification catalyst described in this invention has better thermal stability and its active components are not easily lost.

[0086] Test Example 2

[0087] The catalytic performance and mechanical strength of the etherification catalysts prepared in the test examples and comparative examples were examined.

[0088] Test method: C8 tertiary olefins and methanol were mixed at an alcohol-to-olefin ratio of 2:1 and catalytically reacted at 80°C for 0.5 h. The amount of etherification catalyst added was 5 wt% of the total amount of C8 tertiary olefins and methanol. After the reaction, the content of ethers in the material was tested and the conversion rate of C8 tertiary olefins was calculated. The test results are shown in Table 2.

[0089] The mechanical strength of the etherification catalysts prepared in the examples and comparative examples was tested according to the GB / T12598 method, and the test results are shown in Table 2.

[0090] Table 2

[0091] Example No. C8 tertiary olefin conversion / % Mechanical strength (round ball % after grinding) Example 1 97.2 95.1 Example 2 96.5 94.2 Example 3 95.3 93.6 Example 4 94.5 92.9 Example 5 93.4 97.2 Example 6 93.6 93.1 Example 7 92.4 92.6 Comparative Example 1 85.6 91.2 Comparative Example 2 72.3 92.3 Comparative Example 3 69.5 92.6

[0092] As shown in Table 2, the etherification catalyst prepared by the method described in this invention has higher catalytic activity and higher mechanical strength, making it more suitable for catalyzing the etherification reaction of C8 tertiary olefins and possessing broad industrial application prospects.

[0093] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing an etherification catalyst, characterized in that, The method includes the following steps: (1) In the presence of a pore-forming agent, a dispersant and an initiator, the polymer monomers are subjected to a first-stage polymerization reaction and a second-stage polymerization reaction in sequence to obtain macroporous white spheres; (2) The macroporous white spheres are immersed in haloalkanes for swelling, then the first sulfonating agent is used to carry out a first-stage sulfonation reaction with the swollen material, then the haloalkanes in the reacted material are removed, and the material after removing the haloalkanes is used to carry out a second-stage sulfonation reaction with the second sulfonating agent. The polymerization monomer is a combination of halostyrene and vinylbenzene, wherein the halostyrene is fluorostyrene and / or chlorostyrene, and the temperature of the second-stage polymerization reaction is 5-80°C higher than the temperature of the first-stage polymerization reaction.

2. The method according to claim 1, characterized in that, In the polymer monomer, the content of the halostyrene is 0.2-0.7 wt%, and the content of the vinylbenzene is 0.3-0.8 wt%.

3. The method according to claim 1 or 2, characterized in that, The amount of the initiator is 5-10 parts by weight relative to 100 parts by weight of the polymeric monomer, the amount of the porogen is 50-200 parts by weight, and the amount of the dispersant is 20-50 parts by weight.

4. The method according to any one of claims 1-3, characterized in that, The conditions for the first-stage polymerization reaction include: a temperature of 30-180℃ and a time of 1-12 hours; and / or The conditions for the two-stage polymerization reaction include: a temperature of 40-200℃ and a time of 1-12h.

5. The method according to any one of claims 1-4, characterized in that, The conditions for the first-stage sulfonation reaction include: a temperature of 60-140℃ and a time of 8-24 hours; and / or The conditions for the two-stage sulfonation reaction include: a temperature of 60-140℃ and a time of 8-24h.

6. The method according to claim 1 or 5, characterized in that, The ratio of the total weight of the first sulfonating agent and the second sulfonating agent, the weight of the macroporous white spheres, and the weight of the haloalkane is 1-6:1:2-5; and / or The weight ratio of the first sulfonating agent to the second sulfonating agent is 1:0.9-1.

2.

7. The method according to any one of claims 1-6, characterized in that, The dispersant is selected from at least one of polyvinyl alcohol, gelatin, saponified styrene-maleic anhydride copolymer, hydroxypropyl methylcellulose, and polyacrylamide; and / or The pore-forming agent is selected from at least one of n-hexane, benzene, toluene, xylene, and liquid paraffin; The initiator is selected from N,N-dimethylformamide and / or benzoyl peroxide.

8. The method according to any one of claims 1-7, characterized in that, The haloalkane is selected from at least one of monochloroethane, dichloroethane, and tetrachloroethane; and / or The first sulfonating agent and the second sulfonating agent are each selected from at least one of concentrated sulfuric acid, chlorosulfonic acid, fluorosulfonic acid and fuming sulfuric acid.

9. The etherification catalyst prepared by the method according to any one of claims 1-8.

10. The application of the etherification catalyst according to claim 9 in the catalytic etherification reaction of C8 tertiary olefins with lower alcohols.

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