Catalyst for preparing secondary alcohol by catalytic hydration of alpha-olefin, its preparation method and application

Abstract

The application relates to the technical field of catalysts, and discloses a catalyst for preparing secondary alcohol through catalytic hydration of alpha-olefin, a preparation method and application thereof. The method comprises the following steps: under the catalysis of a catalyst, 1,3,5-tris(4-aminophenyl)benzene and 2,5-dihydroxy-p-xylylene glycol are subjected to a first reaction in a first organic solvent under the condition of air isolation to obtain a TAPB-DHTP-COF material; the TAPB-DHTP-COF material and a reducing agent are subjected to a second reaction in a second organic solvent in the presence of an inert atmosphere, and then the obtained reaction product and a sulfonating agent are subjected to a third reaction. The catalyst prepared according to the method has high stability, the preparation method is simple, the product yield is high in the catalytic hydration of alpha-olefin to prepare secondary alcohol, and the industrialized conversion is easy.

Description

Technical Field

[0001] This invention relates to the field of catalyst technology, specifically to a catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols, its preparation method, and its application. Background Technology

[0002] Olefin hydration is a crucial pathway for preparing alcohols, efficiently converting olefin feedstocks into high-value-added alcohol products. Depending on the reaction mechanism, various methods can be used to activate olefin double bonds and introduce hydroxyl groups, resulting in structurally diverse alcohols and leading to a variety of olefin hydration methods and corresponding catalyst systems. Based on reaction pathway characteristics, olefin hydration can be mainly classified into three categories: direct hydration, indirect hydration, and unconventional hydration. Specific implementation methods include strong acid hydrolysis, esterification-hydrolysis, transition metal-catalyzed hydration, hydroboration-oxidation hydrolysis, olefin tandem hydroxylation, photocatalysis, and bio-enzyme catalysis. Early industrial applications often used sulfuric acid-catalyzed olefin hydration to prepare alcohols. While this method was simple to operate and used readily available feedstocks, it suffered from poor product selectivity, numerous side reactions, difficulty in catalyst separation, severe equipment corrosion, and environmental pollution, and has therefore been gradually replaced. In subsequent studies, the process of hydrating olefins to prepare alcohols has been continuously improved, and a variety of new catalytic systems have been developed, such as noble metal (palladium, ruthenium, etc.) salts, zeolite molecular sieves, solid acids, ion exchange resins, photocatalysts and bio-enzyme catalysts.

[0003] Higher alcohols refer to higher fatty alcohols with more than 6 carbon atoms. They are mainly used in the synthesis of various ester products, possessing high output and added value, and are widely used in multiple industrial fields. Based on the type of carbon atom bonded to the hydroxyl group, higher alcohols can be classified into primary, secondary, and tertiary alcohols. Among them, secondary higher alcohols have good low-temperature fluidity and high cost-effectiveness, making them more widely used. Their production processes mainly include the n-paraffinic boric acid oxidation method and the higher olefin hydration method. The paraffinic oxidation method has a long process flow and many steps, resulting in lower product purity and a greater variety of impurities; while the higher olefin hydration method has the advantages of a shorter process flow and higher product quality. However, the preparation of secondary higher alcohols from α-olefins via direct catalytic hydration still faces key bottlenecks such as difficulty in reaction and low conversion rates. This is mainly because higher olefins have a large number of carbon atoms and poor water solubility, leading to low hydration reaction rates and high reaction difficulty. Furthermore, as the carbon chain length increases, olefins are more prone to breakage, further reducing the conversion rate. Therefore, developing efficient hydration catalysts and corresponding processes to achieve highly selective hydration of α-olefins to prepare higher carbon secondary alcohols is a topic of significant research importance and technical challenge. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems of poor product selectivity, numerous side reactions, difficult catalyst separation, severe equipment corrosion, and serious environmental pollution in existing catalytic hydration processes for the production of secondary alcohols from α-olefins. This invention provides a catalyst for the catalytic hydration of α-olefins to secondary alcohols, its preparation method, and its applications. The catalyst prepared according to the method described in this invention exhibits high stability, and the preparation method is relatively simple. In the catalytic hydration of α-olefins to secondary alcohols, it achieves high product yields and is easily industrialized.

[0005] To achieve the above objectives, the present invention provides a method for preparing a catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols. The method includes: under the catalytic action of the catalyst, carrying out a first reaction in a first organic solvent with 1,3,5-tris(4-aminophenyl)benzene and 2,5-dihydroxyterephthalaldehyde under an air-isolated condition to obtain a TAPB-DHTP-COF material; carrying out a second reaction in a second organic solvent with the TAPB-DHTP-COF material and a reducing agent in the presence of an inert atmosphere; and then carrying out a third reaction with the obtained reaction product and a sulfonating agent.

[0006] Preferably, the molar ratio of 1,3,5-tris(4-aminophenyl)benzene to 2,5-dihydroxyterephthalaldehyde is 1:0.5-2.

[0007] Preferably, the catalyst is at least one selected from acetic acid, trifluoroacetic acid, and formic acid.

[0008] Preferably, the first organic solvent is a mixed solution of ethylene glycol dimethyl ether and mesitylene.

[0009] Preferably, the volume ratio of ethylene glycol dimethyl ether to mesitylene is 1:0.5-2.

[0010] Preferably, the conditions for the first reaction include: a temperature of 100-150°C and a time of 2-4 days.

[0011] Preferably, the mass ratio of the TAPB-DHTP-COF material to the reducing agent is 1:0.5-2.

[0012] Preferably, the reducing agent is at least one selected from sodium hydride, lithium aluminum hydride, and calcium hydride.

[0013] Preferably, the conditions for the second reaction include: a temperature of 60-90°C and a time of 0.5-2 hours.

[0014] Preferably, the second organic solvent is at least one of tetrahydrofuran, dioxane, and cyclohexane.

[0015] Preferably, the mass-volume ratio of the TAPB-DHTP-COF material to the sulfonating agent is (50-200) g: 1 mL.

[0016] Preferably, the sulfonating agent is at least one of 1,3-propanesulfonic acid lactone, chlorosulfonic acid, and sulfur trioxide.

[0017] Preferably, the conditions for the third reaction include: a temperature of 10-40°C and a time of 12-48 hours.

[0018] A second aspect of the present invention provides a catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols using the method described above.

[0019] A third aspect of the present invention provides a method for the catalytic hydration of α-olefins to prepare secondary alcohols, characterized in that α-olefins, trifluoroacetic acid and water are reacted under the catalytic action of the catalyst described above.

[0020] Preferably, the mass-volume ratio of the α-olefin, the trifluoroacetic acid, and the water is (50-200) g : (0.05-0.2) L : 1 L.

[0021] Preferably, the reaction conditions include a temperature of 100-150°C and a time of 12-48 hours.

[0022] The method for preparing a catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention uses 1,3,5-tris(4-aminophenyl)benzene and 2,5-dihydroxyterephthalaldehyde as reactants to synthesize a covalent organic framework material. Then, a sulfonating agent is used to covalently link sulfonic acid groups into the COF material framework. The prepared catalyst has good stability and has the advantages of simple and easy-to-control reaction process, high yield of secondary alcohols, and easy industrial conversion in the catalytic hydration of α-olefins to prepare secondary alcohols. Attached Figure Description

[0023] Figure 1 Transmission electron microscopy (TEM) image of the catalyst prepared in Example 1 of this invention, with a scale bar of 30 nm; Figure 2 Transmission electron microscope (TEM) image of the catalyst prepared in Example 1 of this invention, with a scale bar of 5 nm; Figure 3 The XRD pattern of the catalyst prepared in Example 1 of this invention; Figure 4 The infrared spectrum of the catalyst prepared in Example 1 of this invention; Figure 5 This is a schematic diagram showing the change in α-olefin conversion rate with the number of catalyst cycles during the catalytic hydration of α-olefins to prepare secondary alcohols in Example 14 of the present invention. Detailed Implementation

[0024] 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.

[0025] 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.

[0026] The preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention includes: under the catalytic action of the catalyst, 1,3,5-tris(4-aminophenyl)benzene and 2,5-dihydroxyterephthalaldehyde are subjected to a first reaction in a first organic solvent under the condition of air isolation to obtain TAPB-DHTP-COF material; in the presence of an inert atmosphere, the TAPB-DHTP-COF material and a reducing agent are subjected to a second reaction in a second organic solvent, and then the obtained reaction product and a sulfonating agent are subjected to a third reaction.

[0027] In the preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention, the molar ratio of 1,3,5-tris(4-aminophenyl)benzene and 2,5-dihydroxyterephthalaldehyde can be 1:0.5-2, preferably 1:0.8-1.5.

[0028] In the preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention, the catalyst can be at least one selected from acetic acid, trifluoroacetic acid, and formic acid. In the most preferred embodiment, the catalyst is acetic acid. The acetic acid can be used in the form of an aqueous solution, and the concentration of the aqueous solution of acetic acid can be 5-7 mol / L, preferably 5.5-6.5 mol / L.

[0029] In the preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention, the first organic solvent can be a mixed solution of ethylene glycol dimethyl ether and mesitylene. Preferably, the volume ratio of ethylene glycol dimethyl ether to mesitylene is 1:0.5-2, more preferably 1:0.8-1.5.

[0030] In the preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention, the conditions of the first reaction may include: a temperature of 100-150℃ and a time of 2-4 days. Preferably, the conditions of the first reaction include: a temperature of 110-130℃ and a time of 2.5-3.5 days. The first reaction can be carried out under ultrasonic treatment, and the frequency of the ultrasonic treatment can be 20-40 kHz. The specific operation process of the first reaction may include: adding the 1,3,5-tris(4-aminophenyl)benzene and the 2,5-dihydroxyterephthalaldehyde into an ampoule, then adding the first solvent and performing ultrasonic treatment, followed by dropwise addition of the catalyst; degassing the resulting mixture under liquid nitrogen freezing conditions through a "freezing-pump-thawing" cycle, sealing the ampoule under vacuum, and then transferring the sealed ampoule to an oven for reaction. The temperature of the liquid nitrogen can be -196 to -200℃, preferably -196 to -197℃. The vacuum degree of the degassing process can be from 0.05 to 0.1 MPa.

[0031] In the preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention, the mass ratio of the TAPB-DHTP-COF material to the reducing agent can be 1:0.5-2, preferably 1:0.8-1.5. The reducing agent can be at least one selected from sodium hydride, lithium aluminum hydride, and calcium hydride. In the most preferred embodiment, the reducing agent is sodium hydride. The reducing agent is used to reduce the imine bonds in the TAPB-DHTP-COF material.

[0032] In the preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention, the conditions for the second reaction may include: a temperature of 60-90°C and a time of 0.5-2 h. Preferably, the conditions for the second reaction include: a temperature of 65-85°C and a time of 1-1.5 h. The second reaction can be carried out under stirring at a speed of 500-1000 r / min. The specific operation of the second reaction may include: dispersing the TAPB-DHTP-COF material in anhydrous tetrahydrofuran, and then, under an inert atmosphere, adding the resulting suspension dropwise to a mixture containing sodium hydride and mineral oil under stirring. In the mixture containing sodium hydride and mineral oil, the concentration of sodium hydride may be 50-70% by weight, preferably 55-65% by weight.

[0033] In the preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention, the inert atmosphere can be provided by at least one of argon, helium, and neon. In the most preferred embodiment, the inert atmosphere can be provided by argon.

[0034] In the preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention, the second organic solvent can be at least one selected from tetrahydrofuran, dioxane, and cyclohexane. In the most preferred embodiment, the second organic solvent is tetrahydrofuran.

[0035] In the preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention, the mass-to-volume ratio of the TAPB-DHTP-COF material and the sulfonating agent can be (50-200) g: 1 mL, preferably (100-150) g: 1 mL. The sulfonating agent can be at least one selected from 1,3-propanesulfonate lactone, chlorosulfonic acid, and sulfur trioxide. In the most preferred embodiment, the sulfonating agent is 1,3-propanesulfonate lactone.

[0036] In the preparation method of the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols according to the present invention, the conditions for the third reaction may include: a temperature of 10-40℃ and a time of 12-48 h. Preferably, the conditions for the third reaction include: a temperature of 20-35℃ and a time of 15-40 h. The third reaction can be carried out under stirring, with a stirring speed of 500-1000 r / min, preferably 600-800 r / min. The specific operation process of the third reaction may include: adding the sulfonating agent dropwise to the reaction product under stirring; after the reaction is completed, adding water for quenching; and collecting the solid product by vacuum filtration and washing. The conditions for vacuum filtration may include: a vacuum degree of 0.07-0.09 MPa and a time of 10-30 min. The washing process may be performed once or multiple times, preferably multiple times. The reagent used in the washing process may be at least one of anhydrous ethanol, anhydrous methanol, and cyclohexane, preferably anhydrous ethanol.

[0037] This invention also provides a catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols using the above method. The specific surface area of ​​the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols can be 250-300 m². 2 / g, preferably 260-290m 2 / g; pore size is 0.8-2nm, preferably 1-1.5nm.

[0038] The method for preparing secondary alcohols by catalytic hydration of α-olefins according to the present invention comprises: reacting α-olefins, trifluoroacetic acid, and water under the catalytic action of the above-mentioned catalyst. The reaction can be carried out under stirring, and the stirring speed can be 500-1000 r / min.

[0039] In the method for preparing secondary alcohols by catalytic hydration of α-olefins according to the present invention, the mass-volume ratio of the α-olefin, the trifluoroacetic acid and the water can be (50-200) g: (0.05-0.2) L: 1 L, preferably (60-90) g: (0.08-0.15) L: 1 L.

[0040] The following examples further illustrate the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols, its preparation method, and its application. These examples are implemented based on the technical solution of this invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of this invention is not limited to the following examples.

[0041] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following embodiments are commercially available.

[0042] In the following examples and comparative examples, the relevant parameters for the preparation of the catalyst and the catalytic hydration of α-olefins to prepare secondary alcohols were tested according to the following methods: Morphological and structural characterization: The morphology and structure of the catalyst were characterized and analyzed using transmission electron microscopy.

[0043] X-ray diffraction analysis: The structure of the catalyst was characterized and analyzed using an X-ray diffractometer.

[0044] Infrared spectroscopy testing: Infrared spectroscopy testing is performed using a Fourier transform infrared spectrometer. After drying and removing water from the sample, solid samples can be prepared using the KBr pellet method or the ATR attenuated total reflectance method, while liquid samples can be coated onto a salt plate or directly tested using ATR. The instrument scans and records the molecular vibration absorption signals, and the infrared spectrum is obtained after computer processing. The functional groups and molecular structure can be determined by the position, intensity, and shape of the characteristic absorption peaks.

[0045] Specific surface area and pore size analysis: The adsorption method was used under low-temperature nitrogen (77K). After vacuum degassing and impurity removal, the nitrogen adsorption-desorption isotherm was measured at liquid nitrogen temperature. The specific surface area was calculated using the BET equation and analyzed by t-plot / α. s -plot distinguishes between micropore volume and external surface area. The pore size distribution of micropores smaller than 2nm is fitted using HK, SF or DFT models. The resulting adsorption-desorption isotherms are mostly IUPAC type I isotherms. They are rapidly adsorbed and quickly reach saturation in the low specific pressure region, and generally have no obvious hysteresis loop, which can intuitively reflect the adsorption characteristics of micropores.

[0046] Secondary alcohol selectivity: Conversion rate is calculated by the change in the amount of reactants before and after the reaction. The formula is as follows: Conversion rate = (Amount of substrate before reaction) / (Amount of substrate before reaction) / (Amount of reactants ... The conversion rate is calculated as (amount of substrate after reaction) / (amount of substrate before reaction) × 100%. The selectivity is the proportion of the converted substrate that produces the target product, i.e., selectivity = amount of target product / amount of reacted substrate × 100%. Both conversion and selectivity can be obtained quantitatively by gas chromatography. The yield is the product of conversion and selectivity.

[0047] Example 1 Catalysts for the catalytic hydration of α-olefins to prepare secondary alcohols: 0.04 mmol of 1,3,5-tris(4-aminophenyl)benzene and 0.06 mmol of 2,5-dihydroxyterephthalaldehyde were placed in a 10 mL ampoule. A mixed solvent of 0.5 mL of ethylene glycol dimethyl ether and 0.5 mL of mesitylene was added to the ampoule. The mixture was sonicated at 40 kHz for 5 min, and then 0.1 mL of a 6 mol / L aqueous acetic acid solution was added dropwise. The reaction mixture was placed at -196 °C and degassed using a "freeze-pump-thaw" cycle. The degassed process involved evacuating the ampoule to 0.09 MPa using a vacuum pump, sealing the ampoule under vacuum, and then reacting it in an oven at 120 °C for 72 h to obtain the TAPB-DHTP-COF material. 300 mg of the obtained TAPB-DHTP-COF material was dispersed in 40 mL of anhydrous tetrahydrofuran and stirred at 25 °C for 10 min under argon protection. The resulting suspension was then added to 400 mg of a mixture containing sodium hydride and mineral oil (sodium hydride concentration was 60 wt%), and the mixture was stirred at 80 °C for 1 h. After the reaction was completed, the mixture was cooled to 25 °C to obtain an unsulfonated catalyst intermediate. 3 mL of 1,3-propanesulfonic acid lactone was slowly added dropwise to the reaction solution under continuous stirring. After the addition was complete, the reaction mixture was stirred continuously at 25 °C for 24 h. Subsequently, 5 mL of water was added to the reaction solution to quench the reaction. The resulting product was filtered under reduced pressure at a vacuum of 0.08 MPa, and the solid product was washed three times with acetone to obtain catalyst A1. Figure 1 The transmission electron microscope image of catalyst A1 with a scale bar of 30 nm is shown. Figure 2 The transmission electron microscope image of catalyst A1 with a scale bar of 5 nm is shown. Figure 3 The XRD pattern of catalyst A1 is shown, where, ; Figure 4 The infrared spectrum of catalyst A1 is shown.

[0048] Catalytic hydration of α-olefins to prepare secondary alcohols: 82.1 mg α-hexene and 1 mL deionized water were added to the reactor, along with 0.1 mL trifluoroacetic acid and 10 mg catalyst A1. The mixture was stirred at 120 °C for 24 h to obtain secondary alcohol B1.

[0049] Example 2 Catalysts for the catalytic hydration of α-olefins to prepare secondary alcohols: 0.04 mmol of 1,3,5-tris(4-aminophenyl)benzene and 0.04 mmol of 2,5-dihydroxyterephthalaldehyde were placed in a 10 mL ampoule. A mixed solvent of 0.4 mL of ethylene glycol dimethyl ether and 0.6 mL of mesitylene was added to the ampoule. The mixture was sonicated at 40 Hz for 5 min, and then 0.1 mL of a 5.5 mol / L aqueous acetic acid solution was added dropwise. The reaction mixture was placed at -196 °C and degassed using a "freeze-pump-thaw" cycle. The degassed process involved evacuating the ampoule to 0.09 MPa using a vacuum pump, followed by sealing the ampoule under vacuum and reacting it in an oven at 130 °C for 56 h to obtain the TAPB-DHTP-COF material. 450 mg of the obtained TAPB-DHTP-COF material was dispersed in 40 mL of anhydrous tetrahydrofuran and stirred at 25 °C for 10 min under argon protection. The resulting suspension was then added to 370 mg of a mixture containing sodium hydride and mineral oil (sodium hydride concentration was 60 wt%), and the mixture was stirred at 70 °C for 1.5 h. After the reaction was completed, the mixture was cooled to 25 °C to obtain an unsulfonated catalyst intermediate. 3 mL of 1,3-propanesulfonic acid lactone was slowly added dropwise to the reaction solution under continuous stirring. After the addition was complete, the reaction mixture was stirred continuously at 30 °C for 24 h. Subsequently, 5 mL of water was added to the reaction solution to quench the reaction. The resulting product was filtered under reduced pressure at a vacuum of 0.08 MPa, and the solid product was washed three times with acetone to obtain catalyst A2.

[0050] Catalytic hydration of α-olefins to prepare secondary alcohols: 72.5 mg α-hexene and 1 mL deionized water were added to the reactor, along with 0.15 mL trifluoroacetic acid and 10 mg catalyst A2. The mixture was stirred at 110 °C for 36 h to obtain secondary alcohol B2.

[0051] Example 3 Catalysts for the catalytic hydration of α-olefins to prepare secondary alcohols: 0.04 mmol of 1,3,5-tris(4-aminophenyl)benzene and 0.03 mmol of 2,5-dihydroxyterephthalaldehyde were placed in a 10 mL ampoule. A mixed solvent of 0.6 mL of ethylene glycol dimethyl ether and 0.4 mL of mesitylene was added to the ampoule. The mixture was sonicated at 30 MPa Hz for 5 min, and then 0.1 mL of a 6.5 mol / L aqueous acetic acid solution was added dropwise. The reaction mixture was placed at -196 °C and degassed using a "freeze-pump-thaw" cycle. The degassed process involved evacuating the ampoule to 0.09 MPa using a vacuum pump, sealing the ampoule under vacuum, and then reacting it in an oven at 140 °C for 90 h to obtain the TAPB-DHTP-COF material. 250 mg of the obtained TAPB-DHTP-COF material was dispersed in 40 mL of anhydrous tetrahydrofuran and stirred at 25 °C for 10 min under argon protection. The resulting suspension was then added to 400 mg of a mixture containing sodium hydride and mineral oil (sodium hydride concentration was 55 wt%), and the mixture was stirred at 85 °C for 1 h. After the reaction was completed, the mixture was cooled to 25 °C to obtain an unsulfonated catalyst intermediate. 3 mL of 1,3-propanesulfonic acid lactone was slowly added dropwise to the reaction solution under continuous stirring. After the addition was complete, the reaction mixture was stirred continuously at 25 °C for 24 h. Subsequently, 5 mL of water was added to the reaction solution to quench the reaction. The resulting product was filtered under reduced pressure at a vacuum of 0.08 MPa, and the solid product was washed three times with acetone to obtain catalyst A3.

[0052] Catalytic hydration of α-olefins to prepare secondary alcohols: 88.6 mg of α-hexene and 1 mL of deionized water were added to the reactor, along with 0.12 mL of trifluoroacetic acid and 10 mg of catalyst A3. The mixture was stirred at 110 °C for 36 h to obtain secondary alcohol B3.

[0053] Example 4 Secondary alcohols were prepared according to the method in Example 1, except that 82.1 mg of α-hexene was replaced with 98.2 mg of α-heptene during the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in secondary alcohol B4.

[0054] Example 5 Secondary alcohols were prepared according to the method in Example 1, except that 82.1 mg of α-hexene was replaced with 112.2 mg of α-octene during the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in secondary alcohol B5.

[0055] Example 6 Secondary alcohols were prepared according to the method in Example 1, except that 82.1 mg of α-hexene was replaced with 126.2 mg of α-nonene during the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in secondary alcohol B6.

[0056] Example 7 Secondary alcohols were prepared according to the method in Example 1, except that 82.1 mg of α-hexene was replaced with 140.3 mg of α-decene during the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in secondary alcohol B7.

[0057] Example 8 Secondary alcohols were prepared according to the method in Example 1, except that 82.1 mg of α-hexene was replaced with 154.3 mg of α-undecene during the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in secondary alcohol B8.

[0058] Example 9 Secondary alcohols were prepared according to the method in Example 1, except that 82.1 mg of α-hexene was replaced with 168.3 mg of α-dodecene during the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in secondary alcohol B9.

[0059] Example 10 Secondary alcohols were prepared according to the method in Example 1, except that 82.1 mg of α-hexene was replaced with 182.3 mg of α-tridecene during the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in secondary alcohol B10.

[0060] Example 11 Secondary alcohols were prepared according to the method in Example 1, except that 82.1 mg of α-hexene was replaced with 196.4 mg of α-tetradecene during the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in secondary alcohol B11.

[0061] Example 12 Secondary alcohols were prepared according to the method in Example 1, except that 82.1 mg of α-hexene was replaced with 104.1 mg of styrene in the process of catalytic hydration of α-olefins to prepare secondary alcohols, resulting in secondary alcohol B12.

[0062] Example 13 Secondary alcohols were prepared according to the method in Example 1, except that 82.1 mg of α-hexene was replaced with 98.2 mg of 2-methyl-1-ethylene during the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in secondary alcohol B13.

[0063] Example 14 Secondary alcohols were prepared according to the method in Example 1, except that catalyst A1 was reused 10 times during the catalytic hydration of α-olefins to prepare secondary alcohols, and the product of the last preparation was secondary alcohol B14. Figure 5 A schematic diagram showing the change in α-olefin conversion with the number of catalyst cycles during the preparation of secondary alcohol B14 is shown.

[0064] Example 15 Secondary alcohols were prepared according to the method in Example 1, except that the amount of 2,5-dihydroxyterephthalaldehyde was adjusted to 1 mmol in the process of preparing the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in catalyst A15 and secondary alcohol B15.

[0065] Example 16 The secondary alcohol was prepared according to Example 1, except that the amounts of ethylene glycol dimethyl ether and mesitylene were adjusted to 0.7 mL and 0.3 mL, respectively, in the process of preparing the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in catalyst A16 and secondary alcohol B16.

[0066] Example 17 The secondary alcohol was prepared according to Example 1, except that in the process of preparing the catalyst for the catalytic hydration of α-olefins to prepare the secondary alcohol, 400 mg of a mixture containing sodium hydride and mineral oil (sodium hydride concentration of 60% by weight) was adjusted to 200 mg, resulting in catalyst A17 and secondary alcohol B17.

[0067] Example 18 Secondary alcohols were prepared according to the method in Example 1, except that 1,3-propanesulfonic acid lactone was replaced with chlorosulfonic acid in the process of preparing the catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols, resulting in catalyst A18 and secondary alcohol B18.

[0068] Comparative Example 1 The secondary alcohol was prepared according to Example 1, except that 1,3,5-tris(4-aminophenyl)benzene was replaced with 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, to obtain catalyst D1 and secondary alcohol E1.

[0069] Comparative Example 2 The secondary alcohol was prepared according to Example 1, except that 2,5-dihydroxyterephthalaldehyde was replaced with terephthalaldehyde, resulting in catalyst D2 and secondary alcohol E2.

[0070] The performance parameters of the catalysts prepared in the above embodiments and comparative examples are shown in Table 1 below.

[0071] Table 1

[0072] As can be seen from the results in Table 1, the catalyst prepared according to the method described in this invention has a high α-olefin conversion rate and secondary alcohol yield in the hydration of α-olefins to secondary alcohols.

[0073] 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 a catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols, characterized in that, The method includes: reacting 1,3,5-tris(4-aminophenyl)benzene and 2,5-dihydroxyterephthalaldehyde in a first organic solvent under the catalysis of a catalyst in an air-free condition to obtain TAPB-DHTP-COF material; reacting the TAPB-DHTP-COF material and a reducing agent in a second organic solvent in the presence of an inert atmosphere in a second reaction; and then reacting the resulting reaction product with a sulfonating agent in a third reaction.

2. The method according to claim 1, characterized in that, The molar ratio of 1,3,5-tris(4-aminophenyl)benzene to 2,5-dihydroxyterephthalaldehyde is 1:0.5-2; and / or, The catalyst is at least one of acetic acid, trifluoroacetic acid, and formic acid.

3. The method according to claim 1 or 2, characterized in that, The first organic solvent is a mixed solution of ethylene glycol dimethyl ether and mesitylene; Preferably, the volume ratio of ethylene glycol dimethyl ether to mesitylene is 1:0.5-2.

4. The method according to any one of claims 1-3, characterized in that, The conditions for the first reaction include: a temperature of 100-150℃ and a time of 2-4 days.

5. The method according to any one of claims 1-4, characterized in that, The mass ratio of the TAPB-DHTP-COF material to the reducing agent is 1:0.5-2; Preferably, the reducing agent is at least one selected from sodium hydride, lithium aluminum hydride, and calcium hydride.

6. The method according to any one of claims 1-5, characterized in that, The conditions for the second reaction include: a temperature of 60-90°C and a time of 0.5-2 hours; and / or, The second organic solvent is at least one of tetrahydrofuran, dioxane, and cyclohexane.

7. The method according to any one of claims 1-6, characterized in that, The mass-volume ratio of the TAPB-DHTP-COF material to the sulfonating agent is (50-200) g: 1 mL; Preferably, the sulfonating agent is at least one of 1,3-propanesulfonic acid lactone, chlorosulfonic acid, and sulfur trioxide.

8. The method according to any one of claims 1-7, characterized in that, The conditions for the third reaction include: a temperature of 10-40℃ and a time of 12-48h.

9. A catalyst for the catalytic hydration of α-olefins to prepare secondary alcohols, prepared by the method according to any one of claims 1-8.

10. A method for preparing secondary alcohols by catalytic hydration of α-olefins, characterized in that, The α-olefin, trifluoroacetic acid, and water are reacted under the catalytic action of the catalyst described in claim 9.

11. The method according to claim 10, characterized in that, The mass-volume ratio of the α-olefin, the trifluoroacetic acid, and the water is (50-200) g : (0.05-0.2) L : 1 L.

12. The method according to claim 10 or 11, characterized in that, The reaction conditions include a temperature of 100-150℃ and a time of 12-48h.

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