Low-carbon olefin hydrated fiber membranes, their preparation methods and applications

Abstract

This invention relates to the field of olefin hydration, and discloses a low-carbon olefin hydration fiber membrane, its preparation method, and its application. The low-carbon olefin hydration fiber membrane comprises a hollow fiber membrane substrate, a first silane layer, a first functional layer, and a first alkenophilic layer sequentially coated on the inner surface of the hollow fiber membrane substrate from the inside out, and a second silane layer and a second functional layer sequentially coated on the outer surface of the hollow fiber membrane substrate from the inside out; the first functional layer contains amide groups, phenoxy groups, sulfonic acid groups, phosphate groups, pyrrole groups, and furan groups; the first alkenophilic layer contains phenoxy groups; and the second functional layer contains amide groups, pyrrole groups, and furan groups. This low-carbon olefin hydration fiber membrane can improve the contact effect between water and olefins, promote the movement of hydration balance, and reduce olefin aggregation loss.

Description

Technical Field

[0001] This invention relates to the technical field of olefin hydration, specifically to a low-carbon olefin hydration fiber membrane, its preparation method, and its application. Background Technology

[0002] Olefin hydration is an important organic reaction that can be used to prepare alcohols such as sec-butanol, isopropanol, and cyclohexanol. Industrially, sec-butanol is used as a solvent, mixed with methanol in a certain proportion as a component to increase the octane number of gasoline. It can also be used to produce mineral processing agents, herbicides, and plasticizers, but its most important application is in the production of methyl ethyl ketone (MEK), accounting for approximately 90% of its total consumption. MEK is an excellent organic solvent and raw material for organic synthesis, widely used in oil refining, fuels, high-grade coatings, and pharmaceuticals.

[0003] Traditional olefin hydration typically employs the indirect hydration method using sulfuric acid. However, this method suffers from severe equipment corrosion and waste acid disposal problems, and has been gradually replaced by the catalytic direct hydration method. The catalytic direct hydration method generally involves the direct conversion of low-carbon olefins into corresponding low-carbon alcohols under the catalysis of a solid acid.

[0004] Patent application CN104039435A discloses an integrated membrane hydration reactor for producing related alcohol products from olefins using water. This integrated membrane hydration reactor includes: a solid acid olefin hydration catalyst located in the production zone; and a hydrophilic membrane located in the separation zone, capable of selectively pervaporating water unidirectionally under olefin hydration process conditions, and preventing pervaporation of the related alcohol and olefins. The production zone can efficiently form a mixture of the related alcohol and any unreacted water. The separation zone can efficiently form and produce the related alcohol product and the pervaporated water product from the production zone product mixture. This olefin hydration method for producing related alcohol products from olefins using water utilizes the integrated membrane hydration reactor under olefin hydration process conditions.

[0005] Patent application CN104039435A discloses a combination of a hydration catalytic bed and a pervaporation membrane. A water-alcohol mixture is formed using a conventional catalytic bed. Under relatively static conditions, the high-concentration alcohol-water emulsion gradually separates into an alcohol-rich layer and an water-rich layer. The pervaporation membrane then recovers unreacted water from the hydration reaction in the water-rich layer, yielding pure water. This pure water is used to continuously carry out the current or subsequent hydration reactions. Small amounts of alcohol dissolved in the water-rich layer, intercepted by the pervaporation membrane, are continuously concentrated and precipitated into the alcohol-rich layer. The alcohols in the alcohol-rich layer are continuously extracted from the system via an alcohol pipeline. The catalytic bed can be in contact with or not in contact with the pervaporation membrane. When in contact, the catalytic bed can be attached to the outer surface of the hollow fiber membrane or filled into the inner cavity of the hollow fiber membrane. The pervaporation membrane can be directly prepared from inorganic materials, polymeric materials, or organic-inorganic composite materials. Replacing conventional distillation columns with pervaporation membranes for dehydration separates alcohols or concentrated alcohols and water, allowing for the removal of the reaction product alcohols and reuse of water, thereby shifting the hydration equilibrium to the right. However, the catalytic hydration layer and pervaporation membrane are macroscopic combinations. While they offer some benefits in water recovery, alcohol separation, and equilibrium shift, they lack comprehensive microscopic affinity / repulsion modification for the water, alkenes, and alcohols involved in the hydration reaction. Furthermore, the integration of the catalytic layer and membrane separation at a smaller scale is needed to reduce reactor volume and industrial plant footprint. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems of poor water-olefin contact, excessive water-olefin ratio, and low selectivity of target products in the hydration process of low-carbon olefins in the prior art, and to provide a low-carbon olefin hydration fiber membrane, its preparation method, and its application. This low-carbon olefin hydration fiber membrane can improve the water-olefin contact effect, promote the movement of hydration balance, and reduce the loss of olefin aggregation.

[0007] To achieve the above objectives, a first aspect of the present invention provides a low-carbon olefin hydrated fiber membrane, wherein the low-carbon olefin hydrated fiber membrane comprises a hollow fiber membrane substrate, a first silane layer, a first functional layer, and a first alkenophilic layer sequentially coated on the inner surface of the hollow fiber membrane substrate from the inside out, and a second silane layer and a second functional layer sequentially coated on the outer surface of the hollow fiber membrane substrate from the inside out; the first functional layer contains amide groups, phenoxy groups, sulfonic acid groups, phosphate groups, pyrrole groups, and furan groups; the first alkenophilic layer contains phenoxy groups; and the second functional layer contains amide groups, pyrrole groups, and furan groups.

[0008] A second aspect of the present invention provides a method for preparing a low-carbon olefin hydrated fiber membrane, wherein the method includes:

[0009] (1) The hollow fiber membrane substrate is subjected to silanization treatment to obtain a silanized hollow fiber membrane;

[0010] (2) In the presence of the first functional component, the inner surface of the silanized hollow fiber membrane described in step (1) is subjected to a first functional treatment, and then in the presence of the first alkene-loving component, the inner surface of the hollow fiber membrane after the first functional treatment is subjected to a first alkene-loving treatment to obtain the hollow fiber membrane after the first alkene-loving treatment.

[0011] (3) In the presence of the second functional component, the outer surface of the hollow fiber membrane after the first olefinic treatment in step (2) is subjected to a second functional treatment to obtain a low-carbon olefin hydrated fiber membrane.

[0012] The first functional component contains amide, phenoxy, sulfonic acid, phosphoric acid, pyrrole, and furanyl groups; the first alkenyl group contains phenoxy groups; and the second functional component contains amide, pyrrole, and furanyl groups.

[0013] The third aspect of this invention provides the application of the low-carbon olefin hydration fiber membrane described in the first aspect or the low-carbon olefin hydration fiber membrane prepared by the preparation method described in the second aspect in the low-carbon olefin hydration reaction.

[0014] The inventors of this invention discovered during their research on the hydration of low-carbon olefins that, when using existing solid acid catalysts such as strong acid resins and ZSM-5 molecular sieves to catalyze olefin hydration, the single-pass conversion rate of olefins is significantly lower than the thermodynamic equilibrium conversion rate (generally 3-8%). Low-carbon olefins are generally poorly soluble in water; even with excess water, the two remain incompatible. From the perspective of using excess reactants to further shift the hydration equilibrium to the right, the effect is not significant, only achieving a dilution effect on the product low-carbon alcohols. Solid acid catalysts have good water binding properties but poor compatibility with olefins. Olefins are difficult to adsorb onto the water-saturated solid acid catalyst surface, resulting in difficulty in activating double bonds. To improve the catalytic effect of solid acids, modification mainly focuses on increasing acid strength and density, but this approach leads to side reactions such as olefin chelation, resulting in reduced yield and selectivity of low-carbon alcohols.

[0015] The low-carbon olefin hydrated fiber membrane provided by the present invention has a first silane layer and a second silane layer that can improve the stability and extend the service life of the subsequent first functional layer, first alkene-loving layer and second functional layer. The first functional layer, the first alkene-loving layer and the second functional layer solve the mass transfer problem, balance driving problem and product yield selectivity problem of the prior art from the microscopic mechanism, and improve the product selectivity.

[0016] The low-carbon olefin hydration fiber membrane provided by this invention is applicable not only to olefin hydration reactions with an olefin content of more than 80%, but also to olefin hydration reactions with a low-carbon olefin content of less than 80%, greatly expanding the range of materials that can be processed in olefin hydration reactions, and is particularly suitable for dilute olefin hydration. Detailed Implementation

[0017] 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.

[0018] In this invention, the groups and their contents in the first silane layer, the second silane layer, the first functional layer, the first alkenophilic layer, and the second functional layer were all determined by infrared spectroscopy. The specific testing conditions were KBr tableting at 400 cm⁻¹. -1 -4000cm -1 The content of functional groups in each layer was obtained by step-by-step measurement during the preparation process, and the scanning was performed within the range.

[0019] In this invention, the thicknesses of the first silane layer, the second silane layer, the first functional layer, the first alkenophilic layer, and the second functional layer are all measured by an X-ray fluorescence thickness gauge.

[0020] The first aspect of the present invention provides a low-carbon olefin hydrated fiber membrane, wherein the low-carbon olefin hydrated fiber membrane comprises a hollow fiber membrane substrate, a first silane layer, a first functional layer and a first alkenophilic layer sequentially coated on the inner surface of the hollow fiber membrane substrate from the inside to the outside, and a second silane layer and a second functional layer sequentially coated on the outer surface of the hollow fiber membrane substrate from the inside to the outside; the first functional layer contains amide groups, phenoxy groups, sulfonic acid groups, phosphate groups, pyrrole groups and furan groups; the first alkenophilic layer contains phenoxy groups; and the second functional layer contains amide groups, pyrrole groups and furan groups.

[0021] The inner surface of the hollow fiber membrane matrix is ​​coated with a first functional layer and a first alkenophilic layer. The first functional layer is the main site of olefin hydration reaction. This layer contains alkenophilic groups (for enriching olefins), hydrophilic groups (for enriching water), catalytic groups (for activating olefins, and rationally controlling acid strength through the synergistic combination of groups), and low-carbon alcohol repulsion groups (for transferring the low-carbon alcohols generated in the reaction to the outside of the reaction system, promoting the hydration reaction to move to the right).

[0022] By coating the first alkenophilic layer, olefins are enriched. The olefins enriched in the first alkenophilic layer react with water transferred through the pores of the hollow fiber membrane matrix on the inner side of the first alkenophilic layer (i.e., the first functional layer). Due to the small thickness of this reaction interface and the limited exothermic effect of hydration, runaway temperatures that could lead to catalyst sintering or deactivation are avoided. Because the catalyst in this reaction layer has moderate acid strength, it does not cause side reactions such as olefin condensation or lower alcohol condensation, resulting in a significant improvement in the yield and selectivity of lower alcohols. Furthermore, the first functional layer (reaction layer) contains lower alcohol repulsion groups, which allow the lower alcohols produced by hydration to be gradually transferred to the aqueous phase outside the matrix under the action of molecular forces along the first functional layer and the matrix pores, thereby promoting a continuous rightward shift in the hydration equilibrium.

[0023] By coating a second functional layer containing hydrophilic groups and low-carbon alcohol repulsion groups, water is enriched on the outer surface and pores of the substrate by the hydrophilic groups, providing microscopic excess water for the hydration reaction. Due to the presence of hydrophilic groups, the macroscopic water-to-olefin ratio requirement of the membrane is significantly reduced, thereby significantly reducing the water circulation and separation load of the entire system. The low-carbon alcohol repulsion groups in the first functional layer and the repulsion groups in the second functional layer work together to continuously transfer the low-carbon alcohols produced by hydration from the reaction zone to the aqueous phase.

[0024] In this invention, the hollow fiber membrane substrate is a hollow cylinder with a hollow internal structure as conventionally defined in the art. The inner surface of the hollow cylinder refers to the inner surface of the hollow cylinder, and the outer surface of the hollow cylinder refers to the outer surface of the hollow cylinder.

[0025] In this invention, there is no particular limitation on the type of low-carbon olefin hydrated fiber membrane. Preferably, the hollow fiber membrane substrate is a hollow ceramic fiber membrane.

[0026] In this invention, the properties of the hollow fiber membrane substrate are not particularly limited. Preferably, the hollow fiber membrane substrate has an inner diameter of 0.1-0.5 mm, an outer diameter of 1.1-2.5 mm, a pore size of 30-80 nm in the fiber membrane wall, and a porosity of 40-60%.

[0027] In this invention, there is no particular limitation on the material of the hollow fiber membrane substrate. Preferably, the hollow fiber membrane substrate is made of silicon dioxide and / or aluminum oxide.

[0028] In this invention, preferably, the thickness of the first silane layer and the second silane layer is 5-8 nm each independently.

[0029] In this invention, it is understood that the preparation process of the first silane layer and the second silane layer involves immersing the hollow fiber membrane substrate in a solution containing silane components, with both the inner and outer surfaces of the hollow fiber membrane in contact with the silane components, and the resulting first silane layer and second silane layer having the same thickness.

[0030] In this invention, preferably, the first silane layer and the second silane layer are each independently provided by at least one of 2-butenyltriethoxysilane, methylvinyldiethoxysilane and allyldimethoxysilane.

[0031] In this invention, preferably, based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the content of amide groups in the first functional layer is 10-17 mmol / m². 2 The phenoxy group content is 9-16 mmol / m 2 The content of sulfonic acid groups is 16-30 mmol / m 2 The phosphate group content is 7-15 mmol / m 2 The content of pyrrole groups is 18-26 mmol / m³. 2 The furanyl content is 3-7 mmol / m 2 The advantage of this preferred embodiment is that it enables the enrichment and activation of reactants and the timely removal of reaction products.

[0032] In this invention, preferably, the thickness of the first functional layer is 7-11 nm. The advantage of this preferred embodiment is that it can simultaneously consider both the reaction rate and the heat of reaction.

[0033] In this invention, preferably, based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the phenoxy content in the first alkenophilic layer is 14-30 mmol / m². 2 The advantage of this preferred embodiment is that it enables the capture and enrichment of olefins in the crude olefin feedstock.

[0034] In this invention, preferably, the thickness of the first olefin-loving layer is 4-6 nm. The advantage of this preferred embodiment is that it balances olefin enrichment and mass transfer, thereby improving reaction performance.

[0035] In this invention, preferably, based on the outer surface area of ​​the dry-based hollow fiber membrane substrate per square meter, the content of amide groups in the second functional layer is 18-35 mmol / m². 2 The content of pyrrole groups is 13-21 mmol / m³. 2 The furanyl content is 2-5 mmol / m 2 The advantage of this preferred embodiment is that it can achieve both water enrichment and low-carbon alcohol separation.

[0036] In this invention, preferably, the thickness of the second functional layer is 5-8 nm. The advantage of this preferred embodiment is that it can balance water enrichment, low-carbon alcohol separation, and mass transfer resistance.

[0037] A second aspect of the present invention provides a method for preparing a low-carbon olefin hydrated fiber membrane, wherein the method includes:

[0038] (1) The hollow fiber membrane substrate is subjected to silanization treatment to obtain a silanized hollow fiber membrane;

[0039] (2) In the presence of the first functional component, the inner surface of the silanized hollow fiber membrane described in step (1) is subjected to a first functional treatment, and then in the presence of the first alkene-loving component, the inner surface of the hollow fiber membrane after the first functional treatment is subjected to a first alkene-loving treatment to obtain the hollow fiber membrane after the first alkene-loving treatment.

[0040] (3) In the presence of the second functional component, the outer surface of the hollow fiber membrane after the first olefinic treatment in step (2) is subjected to a second functional treatment to obtain a low-carbon olefin hydrated fiber membrane.

[0041] The first functional component contains amide, phenoxy, sulfonic acid, phosphoric acid, pyrrole, and furanyl groups; the first alkenyl group contains phenoxy groups; and the second functional component contains amide, pyrrole, and furanyl groups.

[0042] In this invention, the type, material and characteristic parameters of the hollow fiber membrane substrate in step (1) have been described in the first aspect and will not be repeated here.

[0043] In this invention, there is no particular limitation on the preparation method of the hollow fiber membrane matrix. For example, it can be prepared by the following method: First, a casting solution is prepared, and then a hollow fiber preform is prepared by a spinning-phase inversion process. Then, hollow ceramic fibers are obtained by drying and calcination. The preparation conditions of the hollow ceramic fibers are as follows: polyethersulfone (average molecular weight of 1500-3800), N-methylpyrrolidone, ceramic precursor (silica and / or alumina), and polyvinylpyrrolidone K90 are mixed in a mass ratio of (9-18):(65-95):(170-330):(4-9) and stirred at 75-95°C for 40-60 hours. Then, the mixture is allowed to stand for degassing for 7-12 hours to obtain the casting solution. The inner and outer gel baths of the spinneret are filled with deionized water at 0-3℃. The inner diameter of the spinneret is 0.3-0.7 mm and the outer diameter is 1.3-2.7 mm. The casting solution flow rate is 4-8 ml / min, the casting solution pressure inside the spinneret is 150-300 kPa (gauge pressure), the ambient temperature is 20-30℃, and the ambient humidity is 45-60%. The casting solution undergoes solvent exchange with the inner and outer gel baths and solidifies through phase separation to form a hollow fiber preform. After washing the hollow fiber membrane preform 4-8 times with deionized water, it is dried with air at 20-30℃, then heated to 1600-1800℃ at a programmed rate of 0.5-1℃ / min and held at that temperature for 4-8 hours. Finally, it is allowed to cool naturally to 20-30℃ to obtain the hollow ceramic fiber membrane matrix.

[0044] In this invention, preferably, in step (1), the silanization treatment causes the inner and outer surfaces of the hollow fiber membrane to be coated with a first silane layer and a second silane layer, respectively, and the thickness of the first silane layer and the second silane layer is independently 5-8 nm.

[0045] In this invention, the method of silanization is not particularly limited, as long as a first silane layer and a second silane layer can be formed. Preferably, in step (1), the silanization process includes: contacting a silane reagent solution with a hollow fiber membrane substrate, followed by drying and curing. In this invention, the contact method and conditions are not particularly limited. Preferably, the contact method is immersion, and the immersion time is 90-150 seconds. In this invention, the drying and curing conditions are not particularly limited. Preferably, the temperature is 100-120°C, and the time is 30-60 minutes. In this invention, preferably, the drying and curing is carried out under a protective atmosphere, preferably an inert atmosphere and / or nitrogen.

[0046] In this invention, preferably, in step (1), the silane reagent solution is obtained by pre-hydrolyzing a silane reagent, water, and a low-carbon alcohol. In this invention, the pre-hydrolyzing conditions are not particularly limited; preferably, the pre-hydrolyzing time is 12-24 hours.

[0047] In this invention, the content of each component in the silane reagent solution is not particularly limited, as long as the thickness requirements of the first silane layer and the second silane layer are met. Preferably, the volume ratio of silane reagent: water: lower alcohol is (1.7-3.8):(3-5):(90-96).

[0048] In this invention, preferably, the pH value of the silane reagent solution is 7.4-8.3.

[0049] In this invention, preferably, the silane reagent is selected from at least one of 2-butenyltriethoxysilane, methylvinyldiethoxysilane, and allyldimethoxysilane.

[0050] In this invention, there is no particular limitation on the specific type of low-carbon alcohol. Preferably, the aqueous low-carbon alcohol is anhydrous methanol and / or anhydrous ethanol.

[0051] In this invention, preferably, the amount of silane reagent solution used is such that the thickness of the first silane layer and the second silane layer are each independently 5-8 nm.

[0052] In this invention, preferably, in step (2), the first functional treatment causes the inner surface of the silanized hollow fiber membrane described in step (1) to be coated with a first functional layer, the first functional layer containing amide groups, phenoxy groups, sulfonic acid groups, phosphate groups, pyrrole groups, and furan groups.

[0053] In this invention, preferably, based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the content of amide groups in the first functional layer is 10-17 mmol / m². 2 The phenoxy group content is 9-16 mmol / m 2 The content of sulfonic acid groups is 16-30 mmol / m 2 The phosphate group content is 7-15 mmol / m 2 The content of pyrrole groups is 18-26 mmol / m³. 2 The furanyl content is 3-7 mmol / m 2 .

[0054] In this invention, preferably, in step (2), the first olefinic treatment causes the inner surface of the hollow fiber membrane after the first functional treatment to be coated with a first olefinic layer, the first olefinic layer containing phenoxy groups.

[0055] In this invention, preferably, based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the phenoxy content in the first alkenophilic layer is 14-30 mmol / m². 2 .

[0056] In this invention, there is no particular limitation on the method of the first functional treatment. Preferably, in step (2), the first functional treatment includes: contacting the solution containing the first functional component with the inner surface of the silanized hollow fiber membrane described in step (1).

[0057] In this invention, there is no particular limitation on the types of components in the solution containing the first functional component, as long as the requirements of the first functional layer are met. Preferably, in step (2), the solution containing the first functional component contains a first polyether, a first functional component, a first initiator, and water.

[0058] In this invention, the content of each component in the solution containing the first functional component is not particularly limited, as long as it meets the requirements of the first functional layer. Preferably, in the solution containing the first functional component, the mass ratio of the first polyether: the first functional component: the first initiator: water is 100:(3.2-5.3):(0.2-0.6):(1-2).

[0059] In this invention, preferably, the average molecular weight of the first polyether is 500-1000.

[0060] In this invention, there is no particular limitation on the type of the first initiator. Preferably, the first initiator is selected from at least one of azo initiators, organic peroxide initiators, inorganic peroxide initiators, and redox initiators; more preferably, it is selected from at least one of azobisisobutyronitrile, benzoyl peroxide, potassium persulfate, and hydrogen peroxide; and even more preferably, it is selected from benzoyl peroxide.

[0061] In this invention, preferably, the first functional component is provided by amide derivatives, phenoxy derivatives, sulfonic acid derivatives, phosphoric acid derivatives, pyrrole derivatives, or furan derivatives.

[0062] In this invention, preferably, the molar ratio of amide derivatives: phenoxy derivatives: sulfonic acid derivatives: phosphate derivatives: pyrrole derivatives: furan derivatives in the solution containing the first functional component is (13-23): (12-21): (21-39): (9-20): (24-34): (4-9).

[0063] In this invention, there is no particular limitation on the type of amide derivative. Preferably, the amide group is provided by an amide derivative, and more preferably, the amide derivative is selected from at least one of N,N'-dihydroxyethylbisacrylamide, N,N-methylenebisacrylamide, and hexamethylenebisacrylamide.

[0064] In this invention, there is no particular limitation on the type of phenoxy derivative. Preferably, the phenoxy group is provided by a phenoxy derivative, and more preferably, the phenoxy derivative is selected from at least one of 4-methoxystyrene, allyl phenyl ether, and phenyl vinyl ether.

[0065] In this invention, there is no particular limitation on the type of phosphate derivative. Preferably, the phosphate derivative is selected from at least one of (2-fluoro-3,7-dimethyloct-1,6-dien-3-yl)phosphonic hydrogen phosphate, [2-methyl-2-(4-methylpent-3-enyl)cyclopropyl]methylphosphonic hydrogen phosphate, and 2-(phosphoryloxy)propane-1,3-dimethyldimethacrylate.

[0066] In this invention, there is no particular limitation on the type of sulfonic acid derivative. Preferably, the sulfonic acid group is provided by a sulfonic acid derivative, and more preferably, the sulfonic acid derivative is selected from at least one of 4-hydroxy-6-(prop-2-enoylamino)naphthalene-2-sulfonic acid, (Z)-4',4”'-(ethylene-1,2-diyl)bis(([[1,1'-biphenyl]-4-sulfonic acid)) and 4-{(E)-2-[3,5-di(sulfonoxy)phenyl]vinyl}phenyl hydrosulfate.

[0067] In this invention, there is no particular limitation on the type of pyrrole derivative. Preferably, the pyrrole group is provided by a pyrrole derivative, and more preferably, the pyrrole derivative is selected from at least one of 3-isopropenyl-1-methyl-pyrrole, 1-(3-buten-1-yl)-2-vinyl-1H-pyrrole, and 5-allyl-4-methoxy-1,5-dihydro-2H-pyrrole-2-one.

[0068] In this invention, there is no particular limitation on the type of furan derivative. Preferably, the furan group is provided by a furan derivative, and more preferably, the furan derivative is 2-(1-propen-2-yl)furan and / or 2-(2-pentenyl)furan.

[0069] In this invention, the hollow fiber membrane is completely filled with a first functional treatment, so that the first polyether gel solution is coated only on the inner surface and a portion of the pores near the inner surface of the hollow fiber membrane, while the outer surface remains uncoated. The conditions for the first functional treatment are not particularly limited in this invention. Preferably, in step (2), the conditions for the first functional treatment include: introducing a solution containing the first functional component into the inner cavity of the silanized hollow fiber membrane described in step (1), with the back pressure at the inner cavity outlet measured by a gauge pressure gauge being 10-20 kg. Preferably, the first functional treatment further includes, after introducing the solution containing the first functional component, treatment at a protective atmosphere (preferably nitrogen) at 80-100°C for 0.7-1.5 hours; cooling to room temperature, immersing and washing 4-8 times in an organic solvent (preferably benzene) at 70-80°C, followed by drying in a nitrogen atmosphere. By pressurizing and pumping the first polyether gel into the hollow fiber membrane cavity, the cavity is completely filled, avoiding coating the first functional component onto the outer surface of the hollow fiber membrane. Preferably, the first polyether is removed by washing with benzene. This operation is simple and low in cost.

[0070] In this invention, there is no particular limitation on the amount of solution containing the first functional component. Preferably, the amount of solution containing the first functional component is such that the thickness of the first functional layer of the low-carbon olefin hydrated fiber membrane is 7-11 nm.

[0071] In this invention, there is no particular limitation on the method of the first olefinic treatment. Preferably, in step (2), the first olefinic treatment includes: contacting a solution containing the first olefinic component with the inner surface of the hollow fiber membrane after the first functional treatment.

[0072] In this invention, preferably, in step (2), the solution containing the first alkenophilic component contains a second polyether, the first alkenophilic component, a second initiator, and water.

[0073] In this invention, the content of each component in the solution containing the first olefinic component is not particularly limited. Preferably, in the solution containing the first olefinic component, the mass ratio of the second polyether: the first olefinic component: the second initiator: water is 100:(3.8-6.2):(0.3-0.6):(1-2).

[0074] In this invention, there is no particular limitation on the type of the second initiator. It can be the same as or different from the type of the first initiator, but preferably the same.

[0075] In this invention, preferably, the average molecular weight of the second polyether is 800-2000.

[0076] In this invention, preferably, the first alkenophilic component is provided by a phenoxy derivative, and more preferably by at least one of 4-methoxystyrene, allyl phenyl ether, and phenyl vinyl ether.

[0077] In this invention, the solution containing the first olefinic component contains a second polyether, the viscosity of which is greater than that of the first polyether. Therefore, the solution containing the first olefinic component cannot penetrate into the pores and is only used to modify the inner surface of the hollow fiber membrane substrate. The conditions for the first olefinic treatment are not particularly limited in this invention. Preferably, in step (2), the conditions for the first olefinic treatment include: introducing the solution containing the first olefinic component into the inner cavity of the hollow fiber membrane after the first functional treatment, with the back pressure at the inner cavity outlet measured by a gauge pressure gauge being 6-13 kg. Preferably, the first olefinic treatment further includes, after introducing the solution containing the first olefinic component, treatment under a protective atmosphere (preferably nitrogen) at 85-110°C for 0.8-1.5 hours, followed by cooling to room temperature. Preferably, the back pressure of the first olefinic treatment is less than the back pressure of the first functional treatment.

[0078] In this invention, there is no particular limitation on the amount of solution containing the first olefinic component. Preferably, the amount of solution containing the first olefinic component is such that the thickness of the first olefinic layer of the low-carbon olefin hydrated fiber membrane is 4-6 nm.

[0079] In this invention, it is understood that the first functional treatment and the first olefinic treatment have respectively filled the hollow fiber membrane cavity with the first polyether and the second polyether. During the operation, the cavity is completely filled. Therefore, the first functional treatment and the first olefinic treatment mainly treat the inner surface part of the hollow fiber membrane, and the subsequent second functional treatment only treats the outer surface part of the hollow fiber membrane.

[0080] In this invention, preferably, in step (2), the second functional treatment causes the outer surface of the hollow fiber membrane after the first olefinic treatment to be coated with a second functional layer, the second functional layer containing amide groups, pyrrole groups, and furan groups.

[0081] In this invention, preferably, based on the outer surface area of ​​the dry-based hollow fiber membrane substrate per square meter, the content of amide groups in the second functional layer is 18-35 mmol / m². 2 The content of pyrrole groups is 13-21 mmol / m³. 2 The furanyl content is 2-5 mmol / m 2 .

[0082] In this invention, there is no particular limitation on the method of the second functional treatment. Preferably, in step (2), the second functional treatment includes: contacting the solution containing the second functional component with the outer surface of the hollow fiber membrane after the first alkene-treated layer.

[0083] In this invention, preferably, in step (3), the solution containing the second functional component contains the second functional component, the third initiator, and the first solvent.

[0084] In this invention, there is no particular limitation on the content of each component in the solution containing the second functional component. Preferably, in step (2), the mass ratio of the second functional component: the third initiator: the first solvent in the solution containing the second functional component is (4.2-7.5):(0.1-0.4):(92-96).

[0085] In this invention, there is no particular limitation on the type of the first solvent. Preferably, in step (2), the first solvent is selected from at least one of toluene, p-xylene, m-xylene, and o-xylene.

[0086] In this invention, there is no particular limitation on the type of the third initiator. It can be the same as or different from the first and second initiators, but preferably the same.

[0087] In this invention, preferably, in step (2), the second functional component is provided by amide derivatives, pyrrole derivatives, or furan derivatives.

[0088] In this invention, preferably, in the solution containing the second functional component, the molar ratio of amide derivative: pyrrole derivative: furan derivative is (23-46): (16-28): (2-7).

[0089] In this invention, amide derivatives, pyrrole derivatives, and furan derivatives have been described above and will not be repeated here.

[0090] In this invention, the conditions for the second functional treatment are not particularly limited, as long as the requirements of the second functional layer are met. Preferably, in step (3), the conditions for the second functional treatment include: a liquid-to-solid volume ratio of the solution containing the second functional component to the hollow fiber membrane after the first olefinic treatment is 2-4, an immersion temperature of 60-80°C, and a time of 1.5-3 hours. Preferably, the second functional treatment further includes immersing and washing the immersion product in an organic solvent (preferably benzene) at 70-80°C 4-8 times. The second polyether is removed by washing with the organic solvent.

[0091] In this invention, there is no particular limitation on the amount of solution containing the second functional component. Preferably, the amount of solution containing the second functional component is such that the thickness of the second functional layer of the low-carbon olefin hydrated fiber membrane is 5-8 nm.

[0092] In this invention, preferably, step (3) further includes post-treatment, which is performed in the presence of a post-treatment agent. The advantage of this preferred embodiment is the removal of residual monomers and improvement of the pore structure.

[0093] In this invention, there is no limitation on the specific operation method of the post-processing. Preferably, the post-processing includes soaking the second functional product obtained from the second functional treatment in a post-processing agent and then drying it.

[0094] In this invention, there is no particular limitation on the type of post-treatment agent. Preferably, the post-treatment agent is selected from at least one of anhydrous ethanol, anhydrous acetone, and anhydrous methanol, and more preferably anhydrous acetone.

[0095] In this invention, there are no particular limitations on the post-treatment conditions. Preferably, the post-treatment conditions include: soaking time of 0.5-1 hour, drying temperature of 120-150°C, and drying time of 0.5-1 hour.

[0096] The third aspect of this invention provides the application of the low-carbon olefin hydration fiber membrane described in the first aspect or the low-carbon olefin hydration fiber membrane prepared by the preparation method described in the second aspect in the low-carbon olefin hydration reaction.

[0097] In this invention, preferably, based on the total amount of olefin reaction raw materials, the content of low-carbon olefins in the olefin reaction raw materials for the low-carbon olefin hydration reaction is 10-100% by volume.

[0098] In this invention, preferably, the low-carbon olefin is a C3 and / or C4 olefin.

[0099] In this invention, preferably, the low-carbon olefin hydration reaction includes: olefin reaction raw materials and water contacting the inner and outer surfaces of the low-carbon olefin hydration fiber membrane respectively to carry out the olefin hydration reaction, thereby obtaining an aqueous solution containing low-carbon alcohols.

[0100] In this invention, there are no particular limitations on the equipment used for the olefin hydration reaction. Preferably, the olefin hydration reaction is carried out in an olefin hydration reactor, and more preferably, a shell-and-tube structure olefin hydration reactor is used, with low-carbon olefin hydration fiber membranes arranged in parallel within the olefin hydration reactor. In this invention, it is understood that water (preferably demineralized water) flows through the shell side of the olefin hydration reactor (i.e., water is in contact with the outer surface of the hollow fiber membrane), and low-carbon olefins flow through the tube side of the olefin hydration reactor (i.e., low-carbon olefins are in contact with the inner surface of the hollow fiber membrane).

[0101] In this invention, the selection range of conditions for the hydration reaction of low-carbon olefins is relatively wide. Preferably, the conditions for the hydration reaction of low-carbon olefins include: a temperature of 80-150℃, a pressure of 500-2000 kPa (gauge pressure), a molar ratio of water to low-carbon olefins of 1.5-4.5, and an olefin reaction feedstock throughput of 520-860 L·m² per square meter of dry-based hollow fiber membrane matrix. -2 h -1 .

[0102] In this invention, preferably, the single-pass olefin conversion rate of olefin hydration is greater than 62%, and the selectivity of lower alcohols is greater than 95%.

[0103] The present invention will be described in detail below through embodiments.

[0104] In this invention, the content of each group in the olefin hydrated fiber membrane is determined by the test method described above.

[0105] In this invention, component analysis employed a 20A high-performance liquid chromatography (HPLC) system (Shimadzu Corporation, Japan, equipped with an autosampler, 10AT and 10AD pumps, and a 20A multi-wavelength UV detector); and an ACQUITY UPLC / Xevo G2 QTOF ultra-high performance liquid chromatography-high resolution tandem mass spectrometry (Waters Corporation, USA, equipped with an autosampler and a diode array UV detector). HPLC conditions were as follows: column: Zorbax Eclipse Plus C18 (4.6 mm × 150 mm, 5 μm); mobile phase: water (containing 0.06% v phosphoric acid): acetonitrile = 95:5; flow rate: 1.0 mL / min; detection wavelength: 210 nm; column temperature: 35 °C; injection volume: 1 μL. Ultra-high performance liquid chromatography (UHPLC) conditions: Column: HSS T3 (2.1 mm × 100 mm, 1.7 μm); Mobile phase: water, methanol; Gradient elution (positive ion mode): 0 min V(water):V(methanol) = 85:15, after 2.5 min V(water):V(methanol) = 55:35, after 4 min V(water):V(methanol) = 10:90, flow rate: 0.45 mL / min; Gradient elution (negative ion mode): 0 min V(water):V(methanol) = 70:30, after 2.5 min V(water):V(methanol) = 55:35, after 3.5 min V(water):V(methanol) = 10:90; flow rate: 0.45 mL / min; Column temperature: 30 ℃; Injection volume: 3 μL. Mass spectrometry conditions: electrospray ionization source (ESI), positive or negative ion scanning mode, capillary voltage 2kV, cone voltage 30eV, ion source temperature: 120℃, desolventizing temperature 450℃, cone gas flow rate 50L / h, desolventizing gas (N2) flow rate 900L / h.

[0106] Example 1

[0107] In this embodiment, the olefin reaction feedstock composition, by volume percentage, includes: isobutane 33.1%, n-butane 8.5%, n-butene 56.7%, and pentane 1.7%.

[0108] The method for preparing the low-carbon olefin hydrated fiber membrane in this embodiment includes: (1) silanizing the inner and outer surfaces of the hollow fiber membrane substrate to obtain a silanized hollow fiber membrane; (2) sequentially performing a first functional treatment and a first olefin-loving treatment on the inner surface of the silanized hollow ceramic fiber membrane obtained in (1), and then performing a second functional treatment on the outer surface to obtain a low-carbon olefin hydrated fiber membrane.

[0109] In this embodiment, the hollow fiber membrane matrix can be prepared by the following method: First, a casting solution is prepared, then a hollow fiber preform is prepared by a spinning-phase inversion process, followed by drying and calcination to obtain hollow ceramic fibers. The preparation conditions of the hollow ceramic fibers are as follows: polyethersulfone (average molecular weight of 2600), N-methylpyrrolidone, ceramic precursor (silica), and polyvinylpyrrolidone K90 are mixed in a mass ratio of 13.5:80:250:6.5, stirred at 85°C for 50 hours, and then allowed to stand for degassing for 9.5 hours to obtain the casting solution. The inner and outer gel baths of the spinneret are deionized water at 1.5°C. The inner diameter of the spinneret is 0.5 mm and the outer diameter is 2 mm. The flow rate of the casting solution is 6 ml / min, the pressure of the casting solution in the spinneret is 225 kPa (gauge pressure), the ambient temperature is 25°C, and the ambient humidity is 52.5%. The casting solution undergoes solvent exchange with the inner and outer gel baths and solidifies to form a hollow fiber preform. The hollow fiber membrane preform was washed six times with demineralized water, dried with air at 25°C, and then heated to 1700°C using a programmed temperature increase of 0.7°C / min, held at that temperature for 6 hours, and then allowed to cool naturally to 25°C to obtain the hollow ceramic fiber membrane matrix. The hollow ceramic fibers have an inner diameter of 0.3 mm, an outer diameter of 1.3 mm, a pore size of 55 nm in the fiber membrane wall, and a porosity of 50%.

[0110] The hollow fiber membrane substrate was then contacted with a silane reagent solution, followed by drying and curing to obtain a silanized hollow fiber membrane. The silane reagent solution was obtained by mixing a silane reagent, water, and anhydrous low-carbon alcohol, followed by pre-hydrolysis. The pre-hydrolysis time was 18 hours. The volume ratio of silane reagent:water:anhydrous low-carbon alcohol was 2.7:4:93. The pH of the silane reagent solution was 7.8. The silane reagent was methylvinyldiethoxysilane. The anhydrous low-carbon alcohol was anhydrous methanol. The contact condition was immersion for 120 seconds. The drying and curing conditions were a temperature of 110°C for 45 minutes under a nitrogen atmosphere. The amount of silane reagent solution used resulted in independent thicknesses of 6.5 nm for both the first and second silane layers.

[0111] The inner surface of the silanized hollow fiber membrane was then treated with a solution containing the first functional component to obtain a hollow fiber membrane with the first functional treatment. The solution containing the first functional component includes a first polyether, the first functional component, a first initiator, and water, wherein the mass ratio of the first polyether to the first functional component to the first initiator to water is 100:4.2:0.4:1.5. The average molecular weight of the first polyether is 750. The first initiator is benzoyl peroxide. The first functional component contains amide derivatives, phenoxy derivatives, sulfonic acid derivatives, phosphoric acid derivatives, pyrrole derivatives, and furan derivatives, wherein the molar ratio of amide derivatives to phenoxy derivatives to sulfonic acid derivatives to phosphoric acid derivatives to pyrrole derivatives to furan derivatives is 18:16.5:30:14.5:29:6.5. The amide derivatives are provided by N,N-methylenebisacrylamide. The phenoxy derivatives are provided by allyl phenyl ether. The phosphate derivative is provided by [2-methyl-2-(4-methylpent-3-enyl)cyclopropyl]methylphosphonophosphate hydrogen ester. The sulfonic acid derivatives were provided by (Z)-4',4”'-(ethylene-1,2-diyl)bis(([[1,1'-biphenyl]-4-sulfonic acid)). The pyrrole derivatives were provided by 1-(3-buten-1-yl)-2-vinyl-1H-pyrrole. The furanyl group was provided by 2-(1-propen-2-yl)furan. The first functional treatment conditions included: introducing a solution containing the first functional component into the inner cavity of the hollow fiber membrane after the silanization treatment in step (1), with a back pressure of 15 kg at the outlet of the inner cavity using a gauge, followed by treatment at 90°C under a nitrogen atmosphere for 1.1 hours; cooling to room temperature, immersing and washing 6 times in hot benzene at 75°C, followed by drying under a nitrogen atmosphere. Based on the inner surface area of ​​the dry hollow fiber membrane matrix per square meter, the content of amide groups in the first functional layer was 13.5 mmol / m². 2 The phenoxy group content was 12.4 mmol / m³. 2 The content of sulfonic acid groups is 22.5 mmol / m 2 The phosphate group content is 10.9 mmol / m 2 The pyrrole group content was 21.7 mmol / m³. 2 The furanyl content was 4.9 mmol / m³. 2 The thickness of the first functional layer is 9nm.

[0112] Subsequently, the inner surface of the hollow fiber membrane after the first functional treatment was subjected to a first olefinic treatment using a first olefinic component to obtain a hollow fiber membrane after the first olefinic treatment. The solution of the first olefinic component contained a second polyether, the first olefinic component, a second initiator, and water, wherein the mass ratio of the second polyether: the first olefinic component: the second initiator: water was 100:5:0.45:1.5. The average molecular weight of the second polyether was 1500. The second initiator was benzoyl peroxide. The first olefinic component was provided by a phenoxy derivative (allyl phenyl ether). The conditions for the first olefinic treatment included: introducing the solution containing the first olefinic component into the inner cavity of the hollow fiber membrane after the first functional treatment in step (2), with the back pressure at the outlet of the inner cavity being 9.5 kg using a gauge, followed by treatment at 97°C under a nitrogen atmosphere for 1.1 hours; cooling to room temperature, and then drying under a nitrogen atmosphere. Based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the phenoxy content in the first olefinic layer was 22 mmol / m². 2 The thickness of the first alkene-loving layer is 5.1 nm.

[0113] Subsequently, a second functional component was used to perform a second functional treatment on the outer surface of the hollow fiber membrane after the first olefin-based treatment, resulting in a low-carbon olefin hydrated fiber membrane. In the solution containing the second functional component, the mass ratio of the second functional component to the third initiator to the second solvent was 5.8:0.2:94. The second solvent was toluene. The second functional component contained amide derivatives, pyrrole derivatives, and furan derivatives, with a molar ratio of amide derivatives:pyrrole derivatives:furan derivatives of 34.5:22:4.5. The amide derivative was N,N-methylenebisacrylamide. The pyrrole derivative was provided by 1-(3-buten-1-yl)-2-vinyl-1H-pyrrole. The furan derivative was provided by 2-(1-propen-2-yl)furan. The second functional treatment conditions included: a liquid-to-solid volume ratio of the solution containing the second functional component to the hollow fiber membrane after the first olefin-based treatment of 3, an immersion temperature of 70°C, a time of 2.2 h, and washing six times with hot benzene at 75°C. The product of the second functional treatment was post-treated in an anhydrous acetone. The post-treatment conditions included: soaking time of 0.7 h, drying temperature of 135 °C, and drying time of 0.7 h. Based on the outer surface area of ​​the dry hollow fiber membrane substrate per square meter, the amide group content in the second functional layer was 26.5 mmol / m². 2 The content of pyrrole groups is 17 mmol / m 2 The furanyl content was 3.5 mmol / m³. 2 The thickness of the second functional layer is 6.4 nm.

[0114] The prepared low-carbon olefin hydration fiber membrane was applied in the hydration of low-carbon olefins using a shell-and-tube olefin hydration reactor. The low-carbon olefin hydration fiber membranes were arranged in parallel within the reactor. Olefins and demineralized water contacted the inner and outer surfaces of the low-carbon olefin hydration fiber membranes, respectively, to carry out the olefin hydration reaction, yielding an aqueous solution containing low-carbon alcohols. The conditions for the olefin hydration reaction included: a temperature of 115℃, a pressure of 1250 kPa (based on a gauge pressure), and an olefin reaction feedstock throughput of 687 L·m² (based on the inner surface area of ​​the dry-basis hollow fiber membrane matrix). -2 h -1 The molar ratio of water to low-carbon olefins was 3.1, the single-pass olefin conversion rate of olefin hydration was 68.4%, and the low-carbon alcohol selectivity was 97.6%.

[0115] Example 2

[0116] The same olefin reaction feedstock as in Example 1 was selected.

[0117] In this embodiment, the hollow fiber membrane matrix can be prepared by the following method: First, a casting solution is prepared, then a hollow fiber preform is prepared by a spinning-phase inversion process, followed by drying and calcination to obtain hollow ceramic fibers. The preparation conditions of the hollow ceramic fibers are as follows: polyethersulfone (average molecular weight of 1600), N-methylpyrrolidone, ceramic precursor (silica), and polyvinylpyrrolidone K90 are mixed at a mass ratio of 10:68:320:5, stirred at 94°C for 58 hours, and then allowed to stand for degassing for 11 hours to obtain the casting solution. The inner and outer gel baths of the spinneret are deionized water at 0.5°C. The inner diameter of the spinneret is 0.4 mm and the outer diameter is 1.4 mm. The flow rate of the casting solution is 4.3 ml / min, the pressure of the casting solution in the spinneret is 155 kPa (gauge pressure), the ambient temperature is 23°C, and the ambient humidity is 58%. The casting solution undergoes solvent exchange with the inner and outer gel baths and solidifies through phase separation to form the hollow fiber preform. The hollow fiber membrane preform was washed eight times with demineralized water, dried with air at 29°C, and then heated to 1780°C at a programmed rate of 0.6°C / min, held at that temperature for 7 hours, and then allowed to cool naturally to 23°C to obtain the hollow ceramic fiber membrane matrix. The hollow ceramic fibers have an inner diameter of 0.2 mm, an outer diameter of 1.2 mm, a pore size of 35 nm in the fiber membrane wall, and a porosity of 45%.

[0118] The hollow fiber membrane substrate was then contacted with a silane reagent solution, followed by drying and curing to obtain a silanized hollow fiber membrane. The silane reagent solution was obtained by mixing a silane reagent, water, and anhydrous low-carbon alcohol, followed by pre-hydrolysis. The pre-hydrolysis time was 23 hours. The volume ratio of silane reagent:water:anhydrous low-carbon alcohol was 3.7:4.8:92. The pH of the silane reagent solution was 8.1. The silane reagent was methylvinyldiethoxysilane. The anhydrous low-carbon alcohol was anhydrous methanol. The contact condition was immersion for 140 seconds. The drying and curing conditions were a temperature of 115°C for 56 minutes under a nitrogen atmosphere. The amount of silane reagent solution used resulted in independent thicknesses of 7.7 nm for both the first and second silane layers.

[0119] The inner surface of the silanized hollow fiber membrane was then treated with a solution containing the first functional component to obtain a hollow fiber membrane with the first functional treatment. The solution containing the first functional component includes a first polyether, the first functional component, a first initiator, and water, wherein the mass ratio of the first polyether to the first functional component to the first initiator to water is 100:5.2:0.5:1.8. The average molecular weight of the first polyether is 700. The first initiator is benzoyl peroxide. The first functional component contains amide derivatives, phenoxy derivatives, sulfonic acid derivatives, phosphoric acid derivatives, pyrrole derivatives, and furan derivatives, wherein the molar ratio of amide derivatives to phenoxy derivatives to sulfonic acid derivatives to phosphoric acid derivatives to pyrrole derivatives to furan derivatives is 22:20:38:19:33:8. The amide derivatives are provided by N,N-methylenebisacrylamide. The phenoxy derivatives are provided by allyl phenyl ether. The phosphate derivative is provided by [2-methyl-2-(4-methylpent-3-enyl)cyclopropyl]methylphosphonophosphate hydrogen ester. The sulfonic acid derivatives are provided by (Z)-4',4”'-(ethylene-1,2-diyl)bis(([[1,1'-biphenyl]-4-sulfonic acid)). The pyrrole derivatives are provided by 1-(3-buten-1-yl)-2-vinyl-1H-pyrrole. The furanyl group is provided by a furan derivative, preferably by 2-(1-propen-2-yl)furan. The first functional treatment conditions include: introducing a solution containing the first functional component into the inner cavity of the hollow fiber membrane after the silanization treatment in step (1), with a back pressure of 18 kg at the outlet of the inner cavity using a gauge, followed by treatment at 95°C for 1.4 hours under a nitrogen atmosphere; cooling to room temperature, washing with hot benzene at 78°C seven times, followed by drying under a nitrogen atmosphere. Based on the inner surface area of ​​the dry hollow fiber membrane matrix per square meter, the content of amide groups in the first functional layer is 16.3 mmol / m². 2 The phenoxy group content was 14.8 mmol / m 2 The content of sulfonic acid groups is 28.1 mmol / m 2 The phosphate group content is 14.0 mmol / m 2The content of pyrrole groups was 24.5 mmol / m³. 2 The furanyl content was 5.9 mmol / m³. 2 The thickness of the first functional layer is 10nm.

[0120] Subsequently, the inner surface of the hollow fiber membrane after the first functional treatment was subjected to a first olefinic treatment using a first olefinic component to obtain a hollow fiber membrane after the first olefinic treatment. The solution of the first olefinic component contained a second polyether, the first olefinic component, a second initiator, and water, wherein the mass ratio of the second polyether: the first olefinic component: the second initiator: water was 100:6.1:0.5:1.8. The average molecular weight of the second polyether was 1000. The second initiator was benzoyl peroxide. The first olefinic component was provided by a phenoxy derivative (allyl phenyl ether). The conditions for the first olefinic treatment included: introducing the solution containing the first olefinic component into the inner cavity of the hollow fiber membrane after the first functional treatment in step (2), with the back pressure of the inner cavity outlet being 12 kg using a gauge pressure gauge, followed by treatment at 106°C under a nitrogen atmosphere for 1.4 hours; cooling to room temperature, and then drying under a nitrogen atmosphere. Based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the phenoxy content in the first olefinic layer was 28.6 mmol / m². 2 The thickness of the first alkene-loving layer is 5.8 nm.

[0121] Subsequently, the outer surface of the hollow fiber membrane after the first olefin-based treatment was subjected to a second functional treatment using a second functional component to obtain a low-carbon olefin hydrated fiber membrane. In the solution containing the second functional component, the mass ratio of the second functional component: the third initiator: the second solvent was 7.4:0.3:93. The second solvent was toluene. The second functional component contained amide derivatives, pyrrole derivatives, and furan derivatives, wherein the molar ratio of amide derivatives:pyrrole derivatives:furan derivatives was 45:27:6. The amide derivatives were provided by N,N-methylenebisacrylamide. The pyrrole derivatives were provided by 1-(3-buten-1-yl)-2-vinyl-1H-pyrrole. The furan derivatives were provided by 2-(1-propen-2-yl)furan. The second functional treatment conditions included: a liquid-to-solid volume ratio of the solution containing the second functional component to the hollow fiber membrane after the first olefin-based treatment in step (2) of 4, an immersion temperature of 77°C, a time of 2.6 h, and washing with hot benzene at 78°C seven times. The product of the second functional treatment was post-treated in an anhydrous acetone. The post-treatment conditions included: soaking time of 0.8 h, drying temperature of 146 °C, and drying time of 0.8 h. Based on the outer surface area of ​​the dry hollow fiber membrane substrate per square meter, the amide group content in the second functional layer was 34.2 mmol / m². 2 The content of pyrrole groups was 20.6 mmol / m³. 2 The furanyl content was 4.5 mmol / m³.2 The thickness of the second functional layer is 7.7 nm.

[0122] The olefin hydration reaction conditions according to the reaction method of Example 1 included: a temperature of 90°C, a pressure of 800 kPa (gauge pressure), a molar ratio of water to low-carbon olefins of 4.2, and an olefin reaction feedstock throughput of 550 L·m² per square meter of dry-based hollow fiber membrane matrix. -2 h -1 The single-pass olefin conversion rate of olefin hydration was 73.5%, and the selectivity for lower alcohols was 98.3%.

[0123] Example 3

[0124] The same olefin reaction feedstock as in Example 1 was selected.

[0125] In this embodiment, the hollow fiber membrane matrix can be prepared by the following method: First, a casting solution is prepared, then a hollow fiber preform is prepared by a spinning-phase inversion process, followed by drying and calcination to obtain hollow ceramic fibers. The preparation conditions of the hollow ceramic fibers are as follows: polyethersulfone (average molecular weight of 3700), N-methylpyrrolidone, ceramic precursor (silica), and polyvinylpyrrolidone K90 are mixed at a mass ratio of 17:93:180:8, stirred at 78°C for 43 hours, and then allowed to stand for degassing for 8 hours to obtain the casting solution. The inner and outer gel baths of the spinneret are deionized water at 2.5°C. The inner diameter of the spinneret is 0.6 mm and the outer diameter is 1.6 mm. The flow rate of the casting solution is 7.6 ml / min. The pressure of the casting solution in the spinneret is 280 kPa (gauge pressure). The ambient temperature is 27°C and the ambient humidity is 50%. The casting solution undergoes solvent exchange with the inner and outer gel baths and solidifies to form a hollow fiber preform. The hollow fiber membrane preform was washed five times with desalinated water, dried with air at 23°C, and then heated to 1650°C at a programmed rate of 0.9°C / min, held at that temperature for 5 hours, and then allowed to cool naturally to 27°C to obtain the hollow ceramic fiber membrane matrix. The hollow ceramic fibers have an inner diameter of 0.4 mm, an outer diameter of 1.4 mm, a pore size of 73 nm in the fiber membrane wall, and a porosity of 56%.

[0126] The hollow fiber membrane substrate was then contacted with a silane reagent solution, followed by drying and curing to obtain a silanized hollow fiber membrane. The silane reagent solution was obtained by mixing a silane reagent, water, and anhydrous low-carbon alcohol, followed by pre-hydrolysis. The pre-hydrolysis time was 14 hours. The volume ratio of silane reagent:water:anhydrous low-carbon alcohol was 1.8:3.2:94. The pH value of the silane reagent solution was 7.6. The silane reagent was methylvinyldiethoxysilane. The anhydrous low-carbon alcohol was anhydrous methanol. The contact condition was immersion for 100 seconds. The drying and curing conditions were a temperature of 106°C for 34 minutes under a nitrogen atmosphere. The amount of silane reagent solution used resulted in independent thicknesses of 5.3 nm for both the first and second silane layers.

[0127] The inner surface of the silanized hollow fiber membrane was then treated with a solution containing the first functional component to obtain a hollow fiber membrane with the first functional treatment. The solution containing the first functional component includes polyether, the first functional component, a first initiator, and water, wherein the mass ratio of the first polyether to the first functional component to the first initiator to water is 100:3.6:0.3:1.3. The average molecular weight of the first polyether is 900. The first initiator is benzoyl peroxide. The first functional component contains amide derivatives, phenoxy derivatives, sulfonic acid derivatives, phosphoric acid derivatives, pyrrole derivatives, and furan derivatives, wherein the molar ratio of amide derivatives to phenoxy derivatives to sulfonic acid derivatives to phosphoric acid derivatives to pyrrole derivatives to furan derivatives is 14:13:22:10:25:5. The amide derivatives are provided by N,N-methylenebisacrylamide. The phenoxy derivatives are provided by allyl phenyl ether. The phosphate derivative is provided by [2-methyl-2-(4-methylpent-3-enyl)cyclopropyl]methylphosphonophosphate hydrogen ester. The sulfonic acid derivatives were provided by (Z)-4',4”'-(ethylene-1,2-diyl)bis(([[1,1'-biphenyl]-4-sulfonic acid)). The pyrrole derivatives were provided by 1-(3-buten-1-yl)-2-vinyl-1H-pyrrole. The furan derivatives were provided by 2-(1-propen-2-yl)furan. The first functional treatment conditions included: introducing a solution containing the first functional component into the inner cavity of the hollow fiber membrane after the silanization treatment in step (1), with a back pressure of 12 kg at the outlet of the inner cavity using a gauge, followed by treatment at 83°C under a nitrogen atmosphere for 0.9 hours; cooling to room temperature, immersing and washing five times in hot benzene at 73°C, followed by drying under a nitrogen atmosphere. Based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the content of amide groups in the first functional layer was 11.2 mmol / m². 2 The phenoxy group content was 10.3 mmol / m 2 The content of sulfonic acid groups is 17.5 mmol / m 2 The phosphate group content is 7.9 mmol / m 2The pyrrole group content is 20 mmol / m 2 The furanyl content is 4 mmol / m 2 The thickness of the first functional layer is 7.6 nm.

[0128] Subsequently, the inner surface of the hollow fiber membrane after the first functional treatment was subjected to a first olefinic treatment using a first olefinic component to obtain a hollow fiber membrane after the first olefinic treatment. The solution of the first olefinic component contained polyether, the first olefinic component, a second initiator, and water, wherein the mass ratio of the second polyether: the first olefinic component: the second initiator: water was 100:3.9:0.4:1.2. The average molecular weight of the second polyether was 1800. The second initiator was benzoyl peroxide. The first olefinic component was provided by a phenoxy derivative (allyl phenyl ether). The conditions for the first olefinic treatment included: introducing the solution containing the first olefinic component into the inner cavity of the hollow fiber membrane after the first functional treatment in step (2), with the back pressure of the inner cavity outlet being 8 kg using a gauge pressure gauge, followed by treatment at 88°C under a nitrogen atmosphere for 0.9 hours; cooling to room temperature, and then drying under a nitrogen atmosphere. Based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the phenoxy content in the first olefinic layer was 15.3 mmol / m². 2 The thickness of the first alkene-loving layer is 4.3 nm.

[0129] Subsequently, the outer surface of the hollow fiber membrane after the first olefin-based treatment was subjected to a second functional treatment using a second functional component to obtain a low-carbon olefin hydrated fiber membrane. In the solution containing the second functional component, the mass ratio of the second functional component to the third initiator to the second solvent was 4.3:0.2:95. The second solvent was toluene. The second functional component contained amide derivatives, pyrrole derivatives, and furan derivatives, wherein the molar ratio of amide derivatives to pyrrole derivatives to furan derivatives was 24:17:3. The amide derivatives were provided by N,N-methylenebisacrylamide. The pyrrole derivatives were provided by 1-(3-buten-1-yl)-2-vinyl-1H-pyrrole. The furan derivatives were provided by 2-(1-propen-2-yl)furan. The second functional treatment conditions included: a liquid-to-solid volume ratio of the solution containing the second functional component to the hollow fiber membrane after the first olefin-based treatment in step (2) of 3; an immersion temperature of 65°C; a immersion time of 1.7 h; and washing with hot benzene at 73°C five times. The product of the second functional treatment was post-treated in an anhydrous acetone. The post-treatment conditions included: soaking time of 0.7 h, drying temperature of 131 °C, and drying time of 0.7 h. Based on the outer surface area of ​​the dry hollow fiber membrane substrate per square meter, the amide group content in the second functional layer was 19.5 mmol / m². 2 The pyrrole group content was 13.8 mmol / m³. 2 The furanyl content was 2.43 mmol / m³.2 The thickness of the second functional layer is 5.3 nm.

[0130] The olefin hydration reaction conditions according to the reaction method of Example 1 included: a temperature of 140°C, a pressure of 1600 kPa (based on a gauge manometer), a molar ratio of water to low-carbon olefins of 1.8, and an olefin reaction feedstock throughput of 850 L·m² per square meter of dry-based hollow fiber membrane matrix. -2 h -1 The single-pass olefin conversion rate of olefin hydration was 63.2%, and the selectivity for lower alcohols was 96.3%.

[0131] Example 4

[0132] The method is the same as in Example 2, except that the composition of the olefin reaction feedstock in this example, by volume percentage, includes: 15.6% isobutane, 6.7% n-butane, 76.5% n-butene, and 1.2% pentane.

[0133] Following the reaction method and conditions of Example 2, in the olefin hydration reactor, the single-pass olefin conversion rate of olefin hydration was 77.2%, and the selectivity for lower alcohols was 98.5%.

[0134] Example 5

[0135] The method is the same as in Example 2, except that the composition of the olefin reaction feedstock in this example, by volume percentage, includes: 6.2% isobutane, 2.1% n-butane, 91.3% n-butene, and 0.4% pentane.

[0136] Following the reaction method and conditions of Example 2, in the olefin hydration reactor, the single-pass olefin conversion rate of olefin hydration was 79.3%, and the selectivity for lower alcohols was 98.7%.

[0137] Example 6

[0138] The method is the same as in Example 2, except that the composition of the olefin reaction feedstock in this example, by volume percentage, includes: 50.4% isobutane, 13.8% n-butane, 30.3% n-butene, and 5.5% pentane.

[0139] Following the reaction method and conditions of Example 2, in the olefin hydration reactor, the single-pass olefin conversion rate of olefin hydration was 69.9%, and the selectivity for lower alcohols was 98.1%.

[0140] Example 7

[0141] The method is the same as in Example 3, except that the product after the second functional treatment in this example is not post-treated with a post-treatment agent.

[0142] Following the reaction method and conditions of Example 3, in the olefin hydration reactor, the single-pass olefin conversion rate of olefin hydration was 62.5%, and the selectivity for lower alcohols was 95.2%.

[0143] Comparative Example 1

[0144] The same olefin reaction feedstock as in Example 5 was used, comprising, by volume percentage: 6.2% isobutane, 2.1% n-butane, 91.3% n-butene, and 0.4% pentane.

[0145] The olefin hydration reactor was filled with Suqing brand SQD-67 styrene-based macroporous strong acid cation exchange resin. The reaction temperature was 150℃, the reaction pressure was 75 kg, and the mass hourly space velocity (HHSV) was 1 h⁻¹. -1 The single-pass conversion rate of n-butene was 11.32%, and the selectivity of lower alcohols was 95.6%.

[0146] Comparative Example 2

[0147] The method of Embodiment 3 is different except that only the first functional processing is performed.

[0148] Following the reaction method and conditions of Example 3, in the olefin hydration reactor, the single-pass olefin conversion rate of olefin hydration was 32.3%, and the selectivity for lower alcohols was 87.9%.

[0149] Comparative Example 3

[0150] The method of Example 3 is followed, except that the first alkene treatment is not performed, and the other preparation steps and processes are the same as in Example 3.

[0151] Following the reaction method and conditions of Example 3, in the olefin hydration reactor, the single-pass olefin conversion rate of olefin hydration was 38.5%, and the selectivity for lower alcohols was 88.2%.

[0152] Comparative Example 4

[0153] The method is the same as in Example 3, except that the second functional treatment is not performed, while the other preparation steps and processes are the same as in Example 3.

[0154] Following the reaction method and conditions of Example 3, in the olefin hydration reactor, the single-pass olefin conversion rate of olefin hydration was 39.6%, and the selectivity for lower alcohols was 88.4%.

[0155] 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 low-carbon olefin hydrated fiber membrane, characterized in that, The low-carbon olefin hydrated fiber membrane comprises a hollow fiber membrane substrate, a first silane layer, a first functional layer, and a first alkenophilic layer sequentially coated on the inner surface of the hollow fiber membrane substrate from the inside out, and a second silane layer and a second functional layer sequentially coated on the outer surface of the hollow fiber membrane substrate from the inside out; the first functional layer contains amide groups, phenoxy groups, sulfonic acid groups, phosphate groups, pyrrole groups, and furan groups; the first alkenophilic layer contains phenoxy groups; and the second functional layer contains amide groups, pyrrole groups, and furan groups. Based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the content of amide groups in the first functional layer is 10-17 mmol / m². 2 The phenoxy group content is 9-16 mmol / m 2 The content of sulfonic acid groups is 16-30 mmol / m 2 The phosphate group content is 7-15 mmol / m 2 The content of pyrrole groups is 18-26 mmol / m³. 2 The furanyl content is 3-7 mmol / m 2 ; Based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the phenoxy content in the first alkenophilic layer is 14-30 mmol / m². 2 ; Based on the surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the content of amide groups in the second functional layer is 18-35 mmol / m². 2 The content of pyrrole groups is 13-21 mmol / m³. 2 The furanyl content is 2-5 mmol / m 2 .

2. The low-carbon olefin hydrated fiber membrane according to claim 1, wherein, The hollow fiber membrane substrate is a hollow ceramic fiber membrane; And / or, the hollow fiber membrane substrate has an inner diameter of 0.1-0.5 mm, an outer diameter of 1.1-2.5 mm, a pore size of 30-80 nm in the fiber membrane wall, and a porosity of 40-60%; And / or, the hollow fiber membrane substrate is made of silicon dioxide and / or aluminum oxide.

3. The low-carbon olefin hydrated fiber membrane according to claim 1 or 2, wherein, The thickness of the first silane layer and the second silane layer is independently 5-8 nm; And / or, the first silane layer and the second silane layer are each independently provided by at least one of 2-butenyltriethoxysilane, methylvinyldiethoxysilane and allyldimethoxysilane.

4. The low-carbon olefin hydrated fiber membrane according to claim 1 or 2, wherein, The thickness of the first functional layer is 7-11 nm.

5. The low-carbon olefin hydrated fiber membrane according to claim 1 or 2, wherein, The thickness of the first alkenophilic layer is 4-6 nm.

6. The low-carbon olefin hydrated fiber membrane according to claim 1 or 2, wherein, The thickness of the second functional layer is 5-8 nm.

7. A method for preparing a low-carbon olefin hydrated fiber membrane, wherein, The method includes: (1) The hollow fiber membrane substrate is subjected to silanization treatment to obtain silanized hollow fiber membrane; (2) In the presence of the first functional component, the inner surface of the silanized hollow fiber membrane described in step (1) is subjected to a first functional treatment, and then in the presence of the first alkene-loving component, the inner surface of the hollow fiber membrane after the first functional treatment is subjected to a first alkene-loving treatment to obtain the hollow fiber membrane after the first alkene-loving treatment. (3) In the presence of the second functional component, the outer surface of the hollow fiber membrane after the first olefinic treatment in step (2) is subjected to a second functional treatment to obtain a low-carbon olefin hydrated fiber membrane. The first functional component contains amide, phenoxy, sulfonic acid, phosphoric acid, pyrrole, and furanyl groups; the first alkenophilic component contains phenoxy groups; and the second functional component contains amide, pyrrole, and furanyl groups. In step (2), the first functional treatment causes the inner surface of the silanized hollow fiber membrane described in step (1) to be coated with a first functional layer, which contains amide groups, phenoxy groups, sulfonic acid groups, phosphate groups, pyrrole groups, and furan groups. Based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the content of amide groups in the first functional layer is 10-17 mmol / m². 2 The phenoxy group content is 9-16 mmol / m 2 The content of sulfonic acid groups is 16-30 mmol / m 2 The phosphate group content is 7-15 mmol / m 2 The content of pyrrole groups is 18-26 mmol / m³. 2 The furanyl content is 3-7 mmol / m 2 ; In step (2), the first olefinic treatment coats the inner surface of the hollow fiber membrane after the first functional treatment with a first olefinic layer, which contains phenoxy groups. Based on the inner surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the phenoxy content in the first alkenophilic layer is 14-30 mmol / m². 2 ; In step (3), the second functional treatment coats the outer surface of the hollow fiber membrane after the first alkenophilic treatment with a second functional layer, which contains amide groups, pyrrole groups, and furan groups. Based on the surface area of ​​the dry-based hollow fiber membrane matrix per square meter, the content of amide groups in the second functional layer is 18-35 mmol / m². 2 The content of pyrrole groups is 13-21 mmol / m³. 2 The furanyl content is 2-5 mmol / m 2 .

8. The method according to claim 7, wherein, In step (1), the hollow fiber membrane substrate is a hollow ceramic fiber membrane; And / or, the hollow fiber membrane substrate has an inner diameter of 0.1-0.5 mm, an outer diameter of 1.1-2.5 mm, a pore size of 30-80 nm in the fiber membrane wall, and a porosity of 40-60%; And / or, the hollow fiber membrane substrate is made of silicon dioxide and / or aluminum oxide.

9. The method according to claim 7 or 8, wherein, In step (1), the silanization process coats the inner and outer surfaces of the hollow fiber membrane with a first silane layer and a second silane layer, respectively, and the thickness of the first silane layer and the second silane layer is 5-8 nm, respectively. And / or, in step (1), the silanization process includes: contacting a silane reagent solution with a hollow fiber membrane substrate, and then drying and curing it.

10. The method according to claim 9, wherein, In step (1), the silane reagent solution is obtained by pre-hydrolysis of silane reagent, water and low-carbon alcohol.

11. The method according to claim 10, wherein, The volume ratio of silane reagent: water: lower alcohol is (1.7-3.8): (3-5): (90-96).

12. The method according to claim 10, wherein, The silane reagent is selected from at least one of 2-butenyltriethoxysilane, methylvinyldiethoxysilane, and allyldimethoxysilane.

13. The method according to claim 7 or 8, wherein, In step (2), the first functional processing includes: contacting the solution containing the first functional component with the inner surface of the silanized hollow fiber membrane described in step (1).

14. The method according to claim 13, wherein, In step (2), the solution containing the first functional component contains the first polyether, the first functional component, the first initiator and water.

15. The method according to claim 14, wherein, In the solution containing the first functional component, the mass ratio of the first polyether to the first functional component to the first initiator to water is 100:(3.2-5.3):(0.2-0.6):(1-2). And / or, the average molecular weight of the first polyether is 500-1000; And / or, the first functional component is provided by amide derivatives, phenoxy derivatives, sulfonic acid derivatives, phosphoric acid derivatives, pyrrole derivatives, or furan derivatives; And / or, in step (2), the conditions for the first functional treatment include: introducing a solution containing the first functional component into the inner cavity of the silanized hollow fiber membrane described in step (1), with the back pressure at the outlet of the inner cavity being 10-20 kg using a gauge pressure gauge.

16. The method according to claim 15, wherein, The molar ratio of amide derivatives: phenoxy derivatives: sulfonic acid derivatives: phosphate derivatives: pyrrole derivatives: furan derivatives is (13-23): (12-21): (21-39): (9-20): (24-34): (4-9).

17. The method according to claim 7 or 8, wherein, The amide group is provided by an amide derivative.

18. The method according to claim 17, wherein, The amide derivative is selected from at least one of N,N'-dihydroxyethylbisacrylamide, N,N-methylenebisacrylamide, and hexamethylenebisacrylamide.

19. The method according to claim 7 or 8, wherein, The phenoxy group is provided by a phenoxy derivative.

20. The method according to claim 19, wherein, The phenoxy derivatives are selected from at least one of 4-methoxystyrene, allylphenyl ether, and phenyl vinyl ether.

21. The method according to claim 7 or 8, wherein, The phosphate group is provided by a phosphate derivative.

22. The method according to claim 21, wherein, The phosphate derivative is selected from at least one of (2-fluoro-3,7-dimethyloct-1,6-dien-3-yl)phosphonophosphate, [2-methyl-2-(4-methylpent-3-enyl)cyclopropyl]methylphosphonophosphate, and 2-(phosphonooxy)propane-1,3-dimethyldimethacrylate.

23. The method according to claim 7 or 8, wherein, The sulfonic acid group is provided by a sulfonic acid derivative.

24. The method according to claim 23, wherein, The sulfonic acid derivative is provided by selecting at least one of 4-hydroxy-6-(prop-2-enoylamino)naphthalene-2-sulfonic acid, (Z)-4',4'''-(ethylene-1,2-diyl)bis(([[1,1'-biphenyl]-4-sulfonic acid)) and 4-{(E)-2-[3,5-di(sulfonoxy)phenyl]vinyl}phenyl hydrosulfate.

25. The method according to claim 7 or 8, wherein, The pyrrole group is provided by a pyrrole derivative.

26. The method of claim 25, wherein, The pyrrole derivatives are selected from at least one of 3-isopropenyl-1-methyl-pyrrole, 1-(3-buten-1-yl)-2-vinyl-1H-pyrrole, and 5-allyl-4-methoxy-1,5-dihydro-2H-pyrrole-2-one.

27. The method according to claim 7 or 8, wherein, The furanyl group is provided by furan derivatives.

28. The method according to claim 27, wherein, The furan derivatives are 2-(1-propen-2-yl)furan and / or 2-(2-pentenyl)furan.

29. The method according to claim 7 or 8, wherein, In step (2), the first olefinic treatment includes: contacting a solution containing the first olefinic component with the inner surface of the hollow fiber membrane after the first functional treatment.

30. The method according to claim 29, wherein, In step (2), the solution containing the first olefinic component contains the second polyether, the first olefinic component, the second initiator, and water.

31. The method according to claim 30, wherein, In the solution containing the first olefinic component, the mass ratio of the second polyether: the first olefinic component: the second initiator: water is 100: (3.8-6.2): ​​(0.3-0.6): (1-2). And / or, the average molecular weight of the second polyether is 800-2000; And / or, the first olefinic component is provided by a phenoxy derivative; And / or, in step (2), the conditions for the first olefinic treatment include: introducing a solution containing the first olefinic component into the inner cavity of the hollow fiber membrane after the first functional treatment, with the back pressure at the outlet of the inner cavity being 6-13 kg as measured by a gauge pressure gauge.

32. The method according to claim 31, wherein, The first alkenophilic component is selected from at least one of 4-methoxystyrene, allyl phenyl ether, and phenyl vinyl ether.

33. The method according to claim 7 or 8, wherein, In step (3), the second functional treatment includes: contacting the solution containing the second functional component with the outer surface of the hollow fiber membrane after the first olefin treatment.

34. The method according to claim 33, wherein, In step (3), the solution containing the second functional component contains the second functional component, the third initiator, and the first solvent.

35. The method according to claim 34, wherein, In step (3), the mass ratio of the second functional component to the third initiator to the first solvent in the solution containing the second functional component is (4.2-7.5):(0.1-0.4):(92-96). And / or, in step (3), the first solvent is selected from at least one of toluene, p-xylene, m-xylene and o-xylene; And / or, in step (3), the second functional component is provided by amide derivatives, pyrrole derivatives, or furan derivatives.

36. The method according to claim 35, wherein, In a solution containing a second functional component, the molar ratio of amide derivatives: pyrrole derivatives: furan derivatives is (23-46): (16-28): (2-7).

37. The method of claim 36, wherein, In step (3), the conditions for the second functional treatment include: the liquid-to-solid volume ratio of the solution containing the second functional component to the hollow fiber membrane after the first olefin treatment is 2-4, the soaking temperature is 60-80℃, and the soaking time is 1.5-3h.

38. The method according to claim 37, wherein, Step (3) further includes post-treatment, which is carried out in the presence of a post-treatment agent selected from at least one of anhydrous ethanol, anhydrous acetone and anhydrous methanol.

39. The method according to claim 38, wherein, The post-treatment conditions include: soaking time of 0.5-1h, drying temperature of 120-150℃, and drying time of 0.5-1h.

40. The method of claim 38, wherein, The post-treatment agent is anhydrous acetone.

41. The use of the low-carbon olefin hydrated fiber membrane according to any one of claims 1-6 or the low-carbon olefin hydrated fiber membrane prepared by the preparation method according to any one of claims 7-40 in the low-carbon olefin hydration reaction.

42. The application according to claim 41, wherein, The raw materials for the low-carbon olefin hydration reaction include: olefin reaction raw materials and water.

43. The application according to claim 42, wherein, Based on the total amount of olefin reaction feedstock, the content of low-carbon olefins in the olefin reaction feedstock is 10-100% by volume.

44. The application according to claim 43, wherein, The low-carbon olefins are C3 and / or C4 olefins.

45. The application according to any one of claims 41-44, wherein, The low-carbon olefin hydration reaction includes: contacting the olefin reaction raw material and water with the inner and outer surfaces of the low-carbon olefin hydration fiber membrane respectively to carry out the low-carbon olefin hydration reaction, thereby obtaining an aqueous solution containing low-carbon alcohols.

46. ​​The application according to claim 45, wherein, The conditions for the hydration reaction of the low-carbon olefins include: a temperature of 80-150℃, a pressure of 500-2000 kPa (gauge pressure), a molar ratio of water to low-carbon olefins of 1.5-4.5, and an olefin reaction feedstock throughput of 520-860 L·m² per square meter of dry-based hollow fiber membrane matrix. -2 h -1 .