Hierarchical pore TS-1 molecular sieve as well as preparation method and application thereof

Abstract

The invention relates to the field of catalytic chemistry, in particular to a hierarchical pore TS-1 molecular sieve as well as a preparation method and application thereof. The preparation method of the hierarchical pore TS-1 molecular sieve provided by the invention comprises the following steps: firstly preparing TS-1 nanocrystals, then introducing an organosilane reagent for silanization treatment and crystallization treatment, and finally calcining and pickling to prepare the hierarchical pore TS-1 molecular sieve. According to the invention, hydrothermal synthesis and silanization modification are combined, and efficient preparation of the hierarchical porous material can be realized through a simple process. The prepared hierarchical pore TS-1 molecular sieve shows excellent activity and selectivity in catalytic performance, especially has significant advantages in macromolecular substrate reaction, is easy to separate and recover, and is suitable for industrial application.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of catalytic chemistry, in particular to a hierarchical pore TS-1 molecular sieve, a preparation method and application thereof. BACKGROUND

[0002] TS-1 molecular sieve is a titanium silicate molecular sieve with MFI topology structure. Due to its unique pore structure and excellent catalytic performance, it has been widely used in chemical industry and fine chemical industry. TS-1 can selectively oxidize a variety of organic compounds under mild conditions with environmentally friendly hydrogen peroxide as oxidant, such as olefin epoxidation, alcohol oxidation and aromatic hydroxylation, etc. Due to its high catalytic activity and selectivity, TS-1 plays an increasingly important role in green chemical industry. However, the traditional TS-1 molecular sieve has the following problems, which limits its further application in actual industrial production:

[0003] Firstly, the pore size of traditional TS-1 molecular sieve is about 0.55 nm, which belongs to microporous material, and is only suitable for the catalysis of small molecule reactants. For larger molecule reactants, due to the pore size limitation, the molecules are difficult to enter the pore, which leads to a significant reduction in reaction efficiency. In addition, due to the large diffusion resistance in micropore, it further affects the catalytic efficiency and reaction rate of TS-1. This diffusion limitation is particularly significant in industrial scale large molecule reactions, which becomes one of the main bottlenecks of TS-1 molecular sieve.

[0004] Secondly, although the micrometer-sized particle structure of traditional TS-1 molecular sieve has certain mechanical strength, in the catalytic reaction, the diffusion path is long, and the utilization rate of active reaction center is low. This not only reduces the catalytic efficiency, but also may cause serious carbon deposition problem, thereby affecting the service life and regeneration ability of the catalyst.

[0005] In order to overcome the above problems, researchers have developed nanoscale TS-1 molecular sieve, whose crystal size is below 100 nm, with higher external specific surface area and shorter diffusion path. This kind of nano molecular sieve can not only significantly improve the catalytic performance of large molecule reactants, but also reduce the reduction of catalytic efficiency caused by diffusion limitation. However, nano TS-1 has significant separation and recovery problems in actual industrial application. Due to its small particle size, traditional solid-liquid separation methods (such as filtration and centrifugation) are difficult to realize fast and efficient recovery, which significantly limits the industrial application potential of nano TS-1 molecular sieve. In addition, nano particles are easy to agglomerate during use, which further reduces the stability and repeatability of its catalytic performance. SUMMARY

[0006] Therefore, the application provides a hierarchical pore TS-1 molecular sieve, a preparation method and application thereof.

[0007] The application provides a preparation method of the hierarchical pore TS-1 molecular sieve, which comprises the following steps:

[0008] S1, mixing, hydrolyzing tetraethyl orthosilicate, a template agent and water to obtain a silicon precursor solution;

[0009] S2, mixing isopropanol, tetrabutyl titanate, a template agent and a solvent to obtain a titanium precursor solution;

[0010] S3, mixing the silicon precursor solution obtained in step S1 and the titanium precursor solution obtained in step S2, removing alcohol, adding a crystallization regulator, pre-crystallizing, crystallizing to obtain TS-1 nanocrystals;

[0011] S4, mixing the TS-1 nanocrystals with an organic silane, performing silanization treatment, and then performing crystallization treatment to obtain TS-1 catalyst raw powder;

[0012] S5, calcining the TS-1 catalyst raw powder to remove the template agent, and then performing acid washing to obtain the hierarchical pore TS-1 molecular sieve;

[0013] The step S1 and the step S2 are not limited in sequence.

[0014] Preferably, in step S4, the organic silane is at least one of 1,8-bis(triethoxysilyl)octane, 1,2-bis(triethoxysilyl)ethane, (triethoxysilyl)cyclohexane and 1,12-bis(triethoxysilyl)dodecane.

[0015] Preferably, in step S1,

[0016] The template agent is tetrapropylammonium hydroxide;

[0017] The molar ratio of the tetraethyl orthosilicate to the template agent is 1:(0.05-0.4).

[0018] The molar ratio of the tetraethyl orthosilicate to water is 1:(4-10);

[0019] The mixing temperature is 20-40 DEG C;

[0020] The hydrolysis temperature is 20-40 DEG C, and the hydrolysis time is 3-7 h.

[0021] Preferably, the molar ratio of the tetraethyl orthosilicate in step S1 to the tetrabutyl titanate in step S2 is (30-50):1.

[0022] In step S2:

[0023] The molar ratio of the tetrabutyl titanate to isopropanol is preferably 1:(30-50);

[0024] The tetrabutyl titanate is added dropwise, and the dropping rate is 2-3 seconds per drop;

[0025] The template agent is tetrapropyl ammonium hydroxide;

[0026] The molar ratio of the tetrabutyl titanate to the template agent is 1:(10-20);

[0027] The molar ratio of the tetrabutyl titanate to water is 1:(200-300).

[0028] The mixing temperature is 10-30°C.

[0029] In step S3, preferably:

[0030] The mixing temperature is preferably 10-20°C;

[0031] The alcohol removal temperature is 90-95°C, and the alcohol removal volume is 1 / 3-1 / 2 of the volume of the solution before alcohol removal;

[0032] The crystallization regulator is ammonium carbonate, and the molar ratio of the crystallization regulator to the tetraethyl orthosilicate in step S1 is 1:(8-12);

[0033] The crystallization regulator is introduced into the system in the form of a crystallization regulator aqueous solution, and the water addition amount in the crystallization regulator aqueous solution is: the volume before alcohol removal-the volume after alcohol removal;

[0034] The pre-crystallization temperature is 80-120°C, and the time is 6-24h;

[0035] The crystallization temperature is 160-180°C, and the time is 48-96h.

[0036] In step S4, preferably:

[0037] The silanization treatment temperature is 80-100°C, and the time is 4-6h;

[0038] The crystallization temperature is 160-180°C, and the time is 48-96h.

[0039] In step S5, preferably:

[0040] The calcination temperature is 500-700°C, and the time is 2-10h;

[0041] The acid solution is a hydrochloric acid solution, and the pickling temperature is 30-50°C.

[0042] The application further provides a hierarchical-pore TS-1 molecular sieve prepared by the preparation method in the above technical solution.

[0043] The application further provides an application of the hierarchical-pore TS-1 molecular sieve in the above technical solution in catalyzing an alkane oxidation reaction or an olefin epoxidation reaction.

[0044] Preferably, the application comprises mixing the hierarchical-pore TS-1 molecular sieve catalyst, a reactant and an oxidant for reaction to obtain a product.

[0045] In the catalytic alkane oxidation reaction, the reactant is cyclohexane or cyclopentane.

[0046] The reactant used is cyclohexane or cyclopentane.

[0047] The oxidant is hydrogen peroxide; the molar ratio of H2O2 to the reactant in the hydrogen peroxide is 2:1.

[0048] The reaction temperature is 50-70 DEG C and the reaction time is 0.5-6 h.

[0049] In the catalytic olefin epoxidation reaction, the reactant is pentene or hexene.

[0050] The reactant used is pentene or hexene.

[0051] The oxidant is hydrogen peroxide; the molar ratio of H2O2 to the reactant in the hydrogen peroxide is 1:(2-3.5).

[0052] The catalyst is added in an amount of 0.5%-8% of the mass of the olefin.

[0053] The reaction is carried out in a solvent medium; wherein the solvent is methanol and acetonitrile.

[0054] The reaction temperature is 40-100 DEG C and the reaction time is 1-5 h.

[0055] The application provides a preparation method of a hierarchical pore TS-1 molecular sieve, and the process is as follows: first, TS-1 nanocrystals are prepared, then, an organosilane reagent is introduced for silanization treatment, crystallization treatment, and finally, calcination and acid washing are performed, so that the hierarchical pore TS-1 molecular sieve is prepared. The bridged organosilane introduced in the application has condensable silanol groups at both ends of the molecule, and the unique bridging property enables the bridged organosilane to form a chemical bond on the surface of the molecular sieve crystal, thereby realizing effective bridging assembly of the nanocrystals. On the one hand, the bridged organosilane can inhibit the excessive crystal growth of the nanomolecular sieve and avoid the formation of large-particle crystals; on the other hand, the bridged organosilane can also construct macroscopic large-size aggregates by inducing self-assembly of the nanoparticles, and endow the material with a hierarchical pore structure. In addition, the chemical properties of the bridged organosilane can be regulated through molecular design, so as to realize accurate control of the pore size and surface properties. This method not only overcomes the separation difficulty of traditional nanomolecular sieves, but also significantly improves the catalytic performance. DETAILED DESCRIPTION

[0056] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0057] In this document, the terms "comprising" or "comprise" do not exclude the presence of other elements or further steps.

[0058] As used herein, the terminology "and / or" includes any and all combinations of one or more of the associated listed items.

[0059] In this document, numerical ranges are recited using "about" to indicate that the numerical values are approximate. For example, unless otherwise indicated, numerical values contained in the specification and claims are intended to include all values a numerical range falling within the recited range, inclusive of the minimum and maximum values of the range, as well as every value within such ranges. Further, when a range is recited, endpoints are included in the range. In addition, where a range is provided, it is intended to include every value within the range, including the range's endpoints. Further, where a range is provided, it is intended to include every value within the range, including the range's endpoints. Also, it is specifically intended that the description include all subclasses of a class. For example, if a class is described including subclasses A, B, and C, it is intended that the description include subclasses A, B, C, A-B, A-C, B-C, and A-B-C.

[0060] In this document, units for data ranges are indicated by units at the right end point only, which means that the units of the left end point and the right end point are the same. For example, 40~60℃ means that the units of the left end point "40" and the right end point "60" are both ℃.

[0061] Only some numerical ranges are specifically disclosed herein. However, any lower limit can be combined with any upper limit to form a range not explicitly recited; and any lower limit can be combined with any other lower limit to form a range not explicitly recited, as can any upper limit with any other upper limit to form a range not explicitly recited. Further, each individual disclosed point or single numerical value can be combined with any other point or single numerical value to form a range not explicitly recited, either as a lower limit or an upper limit.

[0062] In a first aspect, the present application provides a preparation method of a hierarchical pore TS-1 molecular sieve, comprising the following steps:

[0063] S1, mixing tetraethyl orthosilicate, a template agent and water to hydrolyze to obtain a silicon precursor solution;

[0064] S2, mixing isopropyl alcohol, tetrabutyl titanate, a template agent and a solvent to obtain a titanium precursor solution;

[0065] S3, mixing the silicon precursor solution obtained in step S1 and the titanium precursor solution obtained in step S2, removing alcohol, adding a crystallization regulator, pre-crystallizing, and crystallizing to obtain TS-1 nanocrystals;

[0066] S4, mixing the TS-1 nanocrystals with an organosilane to perform silanization treatment, and then performing crystallization treatment to obtain TS-1 catalyst raw powder;

[0067] S5, calcining the TS-1 catalyst raw powder to remove the template agent, and then performing acid washing to obtain a hierarchical pore TS-1 molecular sieve;

[0068] Wherein, step S1 and step S2 are not limited in sequence.

[0069] The present application proposes a preparation method of a hierarchical pore TS-1 molecular sieve based on bridged organosilane, which combines hydrothermal synthesis and silanization modification, and can realize efficient preparation of hierarchical pore materials through a simple process. The prepared hierarchical pore TS-1 molecular sieve has excellent activity and selectivity in catalytic performance, has significant advantages especially in macromolecular substrate reactions, is easy to separate and recover, is suitable for industrial application, and provides a new solution for practical popularization of molecular sieve materials.

[0070] With regard to step S1 :

[0071] S1, mixing tetraethyl orthosilicate, a template agent and water to hydrolyze to obtain a silicon precursor solution.

[0072] In the present application, the source of the tetraethyl orthosilicate is not particularly limited, and a commercially available commercial product can be used.

[0073] In the present application, the template agent is preferably tetrapropylammonium hydroxide. The present application does not have special restrictions on the source of the template agent, and a commercially available commercial product can be used. In the present application, the molar ratio of tetraethyl orthosilicate to template agent is preferably 1:(0.05-0.4), and can be 1:0.05, 1:0.1, 1:0.2, 1:0.3, or 1:0.4.

[0074] In the present application, the water is preferably deionized water. In the present application, the molar ratio of tetraethyl orthosilicate to water is preferably 1:(4-10), and can be 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10.

[0075] In the present application, the temperature of the mixing is preferably 20-40℃, and can be 20℃, 25℃, 30℃, 35℃, or 40℃, and is more preferably 30℃.

[0076] In the present application, the temperature of the hydrolysis is preferably 20-40℃, and can be 20℃, 25℃, 30℃, 35℃, or 40℃, and is more preferably 30℃. The time of the hydrolysis is preferably 3-7h, and can be 3h, 4h, 5h, 6h, or 7h.

[0077] In the present application, step S1 preferably specifically comprises: adding tetraethyl orthosilicate, a template agent, and water into a container, placing it on a magnetic stirrer, stirring and mixing at 20-40℃ to obtain a uniform clear solution, hydrolyzing at the above-mentioned temperature for 3-7h to obtain a silicon precursor solution. The stirring rate of the magnetic stirrer is preferably 400-600rpm, and can be 400rpm, 450rpm, 500rpm, 550rpm, or 600rpm, and is more preferably 500rpm.

[0078] With regard to step S2 :

[0079] S2, mixing isopropyl alcohol, tetrabutyl titanate, a template agent, and a solvent to obtain a titanium precursor solution.

[0080] In the present application, the source of the isopropyl alcohol is not particularly limited, and a commercially available commercial product can be used.

[0081] In the present application, the source of the tetrabutyl titanate is not particularly limited, and a commercially available product can be used. In the present application, the molar ratio of the tetraethyl orthosilicate in step S1 to the tetrabutyl titanate in step S2 is preferably (30-50):1, and can be specifically 30:1, 35:1, 40:1, 45:1, or 50:1. In the present application, the molar ratio of the tetrabutyl titanate to isopropyl alcohol is preferably 1:(30-50), and can be specifically 1:30, 1:35, 1:40, 1:45, or 1:50. In the present application, the tetrabutyl titanate is preferably added dropwise, and the rate of dropwise addition is preferably 2-3 seconds per drop, and more preferably 3 seconds per drop.

[0082] In the present application, the template agent is preferably tetrapropyl ammonium hydroxide. The present application does not have a particular limitation on the source of the template agent, and a commercially available product can be used. In the present application, the molar ratio of the tetrabutyl titanate to the template agent is preferably 1:(10-20), and can be specifically 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19, or 1:20. In the present application, the template agent is preferably introduced into the system in the form of a template agent aqueous solution, and the mass percentage concentration of the template agent aqueous solution is preferably 25wt%

[0083] In the present application, the water is preferably deionized water. In the present application, the molar ratio of the tetrabutyl titanate to water is preferably 1:(200-300), and can be specifically 1:200, 1:210, 1:220, 1:225, 1:230, 1:240, 1:250, 1:260, 1:270, 1:275, 1:280, 1:290, or 1:300.

[0084] In the present application, the temperature condition of step S2 is preferably 10-30℃, and can be specifically 10℃, 15℃, 20℃, 25℃, or 30℃, and more preferably 20℃.

[0085] In the present application, step S2 specifically comprises: adding isopropyl alcohol into a container, then adding the tetrabutyl titanate dropwise under stirring, and after the dropwise addition is completed, adding a template agent and water to obtain a titanium precursor solution. The stirring rate is preferably 400-600 rpm, and can be specifically 400 rpm, 450 rpm, 500 rpm, 550 rpm, or 600 rpm, and more preferably 500 rpm.

[0086] With regard to step S3 :

[0087] S3, mixing the silicon precursor solution obtained in step S1 and the titanium precursor solution obtained in step S2, removing alcohol, adding a crystallization regulator, pre-crystallizing, and crystallizing to obtain TS-1 nanocrystals.

[0088] In the present application, the temperature of the mixing is preferably 10-30℃, and can be specifically 10℃, 15℃, 20℃, 25℃, or 30℃. The mixing is preferably stirring mixing. The stirring rate is preferably 400-600 rpm, and can be specifically 400 rpm, 450 rpm, 500 rpm, 550 rpm, or 600 rpm. The mixing time is preferably 20-40 min, and can be specifically 20 min, 25 min, 30 min, 35 min, or 40 min, and is more preferably 30 min.

[0089] In the present application, the temperature of the alcohol removal is preferably 90-95℃, and can be specifically 90℃, 91℃, 92℃, 93℃, 94℃, or 95℃. The volume of the alcohol removal is 1 / 3-1 / 2 of the volume of the solution before alcohol removal, and is preferably 1 / 3.

[0090] In the present application, the crystallization regulator is preferably ammonium carbonate. In the present application, the molar ratio of the crystallization regulator to tetraethyl orthosilicate in step S1 is preferably 1:(8-12), and can be specifically 1:8, 1:9, 1:10, 1:11, or 1:12. In the present application, the crystallization regulator is preferably introduced into the system in the form of an aqueous solution, i.e., the crystallization regulator is first diluted and dissolved in water to obtain a crystallization regulator aqueous solution, which is then added to the solution after alcohol removal; wherein the amount of water added is: the volume before alcohol removal - the volume after alcohol removal (i.e., the difference between the volumes of the solutions before and after alcohol removal). The crystallization regulator aqueous solution is preferably added dropwise.

[0091] In the present application, after the above process, pre-crystallization is performed. In the present application, the temperature of the pre-crystallization is preferably 80-120℃, and can be specifically 80℃, 85℃, 90℃, 95℃, 100℃, 105℃, 110℃, 115℃, or 120℃. The pre-crystallization time is preferably 6-24 h, and can be specifically 6 h, 8 h, 10 h, 12 h, 14 h, 16 h, 18 h, 20 h, 22 h, or 24 h, and is more preferably 24 h.

[0092] In the present application, after the above pre-crystallization, hydrothermal crystallization is performed. In the present application, the temperature of the crystallization is preferably 160-180℃, and can be specifically 160℃, 165℃, 170℃, 175℃, or 180℃; the crystallization time is preferably 48-96 h, and can be specifically 48 h, 60 h, 72 h, 84 h, or 96 h. After the above crystallization, TS-1 nanocrystals are obtained.

[0093] With regard to step S4 :

[0094] S4, the TS-1 nanocrystals are mixed with an organosilane, silanization treatment is performed, and then crystallization treatment is performed to obtain TS-1 catalyst raw powder.

[0095] In the present application, the organosilane is preferably at least one of 1,8-bis(triethoxysilyl)octane, 1,2-bis(triethoxysilyl)ethane, (triethoxysilyl)cyclohexane, and 1,12-bis(triethoxysilyl)dodecane. In the present application, the amount of the organosilane added is preferably 0.05 to 0.10 of the molar amount of tetraethyl orthosilicate in step S1, and can be specifically 0.05, 0.06, 0.07, 0.075, 0.08, 0.09, or 0.1. The introduction of the above-mentioned organosilane as a bridging agent in the present application can form a chemical bridge between the nanocrystals and the crystal surface through a condensation reaction, and then form a larger size zeolite cluster composed of nanocrystals, which has a multi-level pore inside and has structures such as micropores and mesopores, and can improve its catalytic oxidation ability and be applied to oxidation and epoxidation reactions.

[0096] In the present application, the temperature of the silanization treatment is preferably 80 to 100 DEG C, and can be specifically 80 DEG C, 85 DEG C, 90 DEG C, 95 DEG C, or 100 DEG C, and is more preferably 100 DEG C. The time of the silanization treatment is preferably 4 to 6 hours, and can be specifically 4 hours, 5 hours, or 6 hours. In the present application, the silanization treatment is preferably accompanied by stirring. The silanization treatment forms a bridging structure between the organosilane and the crystal seeds.

[0097] In the present application, after the above-mentioned silanization treatment, hydrothermal crystallization is performed. In the present application, the temperature of the crystallization treatment is preferably 160 to 180 DEG C, and can be specifically 160 DEG C, 165 DEG C, 170 DEG C, 175 DEG C, or 180 DEG C. The time of the crystallization is preferably 48 to 96 hours, and can be specifically 48 hours, 60 hours, 72 hours, 84 hours, or 96 hours. After the above-mentioned crystallization, TS-1 catalyst raw powder is obtained.

[0098] With regard to step S5 :

[0099] S5, calcining the TS-1 catalyst raw powder to remove the template agent, and then acid washing to obtain a hierarchical pore TS-1 molecular sieve.

[0100] In the present application, the temperature of the calcination is preferably 500 to 700 DEG C, and can be specifically 500 DEG C, 550 DEG C, 600 DEG C, 650 DEG C, or 700 DEG C. The time of the calcination is preferably 2 to 10 hours, and can be specifically 2 hours, 4 hours, 6 hours, 8 hours, or 10 hours, and is more preferably 6 to 10 hours. In the present application, the heating rate of the calcination is preferably 2 to 3 DEG C / min, and can be specifically 2 DEG C / min, 2.5 DEG C / min, or 3 DEG C / min. The above-mentioned calcination removes the template agent.

[0101] In the present application, after the above calcination, acid washing is performed. In the present application, the acid solution used in the acid washing is preferably a hydrochloric acid solution. In the present application, the concentration of the acid solution is preferably 0.1-1.0 mol / L, and can be specifically 0.1 mol / L, 0.5 mol / L, 1.0 mol / L, and more preferably 0.5 mol / L. In the present application, the temperature of the acid washing is preferably 30-50℃, and can be specifically 30℃, 35℃, 40℃, 45℃, 50℃, and more preferably 40℃. The time of the acid washing is preferably 1-3 h, and can be specifically 1 h, 2 h, 3 h, and more preferably 2 h. After the above acid washing treatment, the hierarchical pore TS-1 molecular sieve is obtained.

[0102] In a second aspect, the present application also provides a hierarchical pore TS-1 molecular sieve, which is prepared by the preparation method described in the above technical solution. In the present application, the particle size of the obtained hierarchical pore TS-1 molecular sieve is 5-40 μm, and is composed of primary molecular sieve nanoparticles with a size of about 120-200 nm. The TS-1 aggregate synthesized by the method of the present application has the characteristics of conventional nano TS-1 molecular sieves, and at the same time, the large-size aggregate structure effectively simplifies the preparation of the catalyst and the separation process in the reaction process, and in addition, the hierarchical pore structure contained therein can make the diffusion and reaction of substances with a larger kinetic diameter in the pore, and has better reaction activity than the conventional nano TS-1 catalyst.

[0103] In a third aspect, the present application also provides the use of the hierarchical pore TS-1 molecular sieve described in the above technical solution in catalyzing the oxidation reaction of alkanes or the epoxidation reaction of alkenes.

[0104] In the present application, the hierarchical pore TS-1 molecular sieve is used as a catalyst in the above applications.

[0105] In the present application, the use includes mixing the hierarchical pore TS-1 molecular sieve catalyst, the reactants and the oxidizing agent to obtain a product. In the present application, the oxidizing agent is preferably hydrogen peroxide. In the present application, the mass fraction of the hydrogen peroxide is preferably 20%-50%, and more preferably 20%-30%.

[0106] Regarding the catalytic oxidation reaction of alkanes:

[0107] The adopted reactant is preferably cyclohexane or cyclopentane. When the reactant is cyclohexane, catalytic cyclohexane oxidation is used to prepare cyclohexanol ketone. When the reactant is cyclopentane, catalytic cyclopentane oxidation is used to prepare cyclopentanol ketone. In the present application, the molar ratio of H2O2 to the reactant in the hydrogen peroxide is preferably 2:1. In the present application, the amount of the catalyst added is preferably 5% to 7% of the mass of the alkane, and can be specifically 5%, 6%, or 7%. In the present application, the temperature of the reaction is preferably 50 to 70°C, and can be specifically 50°C, 55°C, 60°C, 65°C, or 70°C. The time of the reaction is preferably 0.5 to 6h, and can be specifically 0.5h, 1h, 2h, 3h, 4h, 5h, or 6h, and more preferably 2 to 4h. In the present application, the reaction equipment used is preferably a reaction kettle. The reaction is preferably accompanied by stirring. The stirring rate is preferably 100 to 800rpm, and can be specifically 100rpm, 200rpm, 300rpm, 400rpm, 500rpm, 600rpm, 700rpm, or 800rpm.

[0108] Regarding catalytic olefin epoxidation reaction:

[0109] The reactant used is preferably pentene or hexene, and specifically 1-pentene or 1-hexene. When the reactant is pentene, the catalytic epoxidation of pentene produces epoxypentane. When the reactant is hexene, the catalytic epoxidation of hexene produces epoxyhexane. In the present application, the molar ratio of H2O2 to the reactant in the hydrogen peroxide is preferably 1:(2-3.5), and specifically can be 1:2, 1:2.5, 1:3, 1:3.5. In the present application, the amount of the catalyst added is preferably 0.5%-8% of the mass of the olefin, and specifically can be 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%. In the present application, the reaction preferably takes place in a solvent medium. In the present application, the solvent is preferably methanol and acetonitrile. The mass ratio of the olefin to the solvent is preferably 1:(3-9), and specifically can be 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9. In the solvent, the mass ratio of methanol to acetonitrile is preferably 1:0.5-1.5, and specifically can be 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5. In the present application, the temperature of the reaction is preferably 40-100℃, and specifically can be 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃; the time of the reaction is preferably 1-5h, and specifically can be 1h, 2h, 3h, 4h, 5h. In the present application, the reaction equipment used is preferably a reaction kettle. The reaction preferably takes place with stirring. The stirring rate is preferably 100-800rpm, and specifically can be 100rpm, 200rpm, 300rpm, 400rpm, 500rpm, 600rpm, 700rpm, 800rpm.

[0110] Compared with the prior art, the present application has the following significant advantages. The hierarchical pore TS-1 molecular sieve aggregate prepared from the bridged organosilane has both microporous and mesoporous structures, significantly increases the specific surface area, reduces the diffusion resistance in the reaction process, and improves the transport rate of the reactants and products. The hierarchical pore structure not only provides more catalytically active sites, but also effectively reduces the occurrence of side reactions, significantly improves the conversion rate and selectivity of the reaction. This improved process not only enhances the efficiency of catalysis, simplifies the separation and recovery process of the catalyst, but is more suitable for industrial application, and has high economic benefits and environmental value.

[0111] In order to further understand the present application, the preferred embodiments of the present application are described below in conjunction with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present application, and are not limitations on the claims of the present application.

[0112] Example 1

[0113] S1. Add 6g of tetraethyl orthosilicate to a round-bottom flask, then add an aqueous solution (25wt%) of the template agent tetrapropylammonium hydroxide and deionized water. Place the flask on a magnetic stirrer and stir at 20℃ and 400rpm until a homogeneous and clear solution is obtained. Then, maintain the solution at 20℃ for 3h to hydrolyze and obtain a silicon precursor solution.

[0114] The molar ratio of tetraethyl orthosilicate to tetrapropylammonium hydroxide is 1:0.05. The molar ratio of tetraethyl orthosilicate to deionized water is 1:4.

[0115] S2. At room temperature, a certain amount of isopropanol was measured into a round-bottom flask, and a certain amount of tetrabutyl titanate was slowly added dropwise. The molar ratio of tetraethyl orthosilicate to tetrabutyl titanate was 30:1, the molar ratio of tetrabutyl titanate to isopropanol was 1:30, the dropping rate was 2 drops per second, and the stirring speed was 400 rpm. Then, a certain amount of tetrapropylammonium hydroxide aqueous solution (25 wt%) and deionized water were added. The molar ratio of tetrabutyl titanate to tetrapropylammonium hydroxide was 1:10, and the molar ratio of tetrabutyl titanate to deionized water was 1:200, to obtain a titanium precursor solution.

[0116] S3. The silicon precursor solution obtained in step S1 and the titanium precursor solution obtained in step S2 are mixed at 10°C with a stirring rate of 400 rpm for 20 minutes. Then, the water bath temperature is raised to 90°C to perform alcohol removal. The volume of alcohol removed is 1 / 3 of the original solution volume. After alcohol removal, the solution is cooled to room temperature, and a crystallization regulator solution (ammonium carbonate aqueous solution) is added dropwise. The molar ratio of ammonium carbonate to tetraethyl orthosilicate in step S1 is 1:8, and the amount of water in the ammonium carbonate aqueous solution is: volume before alcohol removal - volume after alcohol removal. After the addition is complete, stirring continues for 0.5 hours. The solution is then transferred to a crystallization vessel and pre-crystallized at 80°C for 6 hours; subsequently, it is hydrothermally crystallized at 160°C for 48 hours to obtain TS-1 nanocrystals.

[0117] S4. The TS-1 nanocrystals and 1,8-bis(triethoxysilyl)octane are stirred at 80°C for 4 hours to perform silanization treatment, forming a bridging structure between the organosilane and the seed crystals. The amount of 1,8-bis(triethoxysilyl)octane added is 0.05 of the molar amount of tetraethyl orthosilicate in step S1. Subsequently, the mixture is subjected to hydrothermal crystallization at 160°C for 48 hours to obtain the TS-1 catalyst powder.

[0118] S5. The TS-1 catalyst powder was calcined at 500℃ for 2h at a heating rate of 2℃ / min to remove the template agent, and then treated with 0.1mol / L hydrochloric acid solution at 30℃ for 1h to obtain hierarchical porous TS-1 molecular sieve.

[0119] Example 2

[0120] S1, 6 g of tetraethyl orthosilicate was taken into a round-bottom flask, then an aqueous solution of template agent tetrapropyl ammonium hydroxide (25 wt%) and deionized water were added, and the mixture was stirred on a magnetic stirrer at 25°C and 450 rpm until a uniform clear solution was obtained, and then hydrolysis was carried out at 25°C for 4 h to obtain a silicon precursor solution.

[0121] The molar ratio of tetraethyl orthosilicate to tetrapropyl ammonium hydroxide was 1:0.1. The molar ratio of tetraethyl orthosilicate to deionized water was 1:5.

[0122] S2, at room temperature, a certain amount of isopropyl alcohol was measured into a round-bottom flask, and a certain amount of tetrabutyl titanate was slowly added dropwise, wherein the molar ratio of ethyl orthosilicate to tetrabutyl titanate was 35:1, the molar ratio of tetrabutyl titanate to isopropyl alcohol was 1:35, the dropwise addition rate was 3 seconds per drop, and the stirring rate was 450 rpm, then a certain amount of aqueous solution of tetrapropyl ammonium hydroxide (25 wt%) and deionized water was added, the molar ratio of tetrabutyl titanate to tetrapropyl ammonium hydroxide was 1:12, and the molar ratio of tetrabutyl titanate to deionized water was 1:225 to obtain a titanium precursor solution.

[0123] S3, the silicon precursor solution obtained in step S1 and the titanium precursor solution obtained in step S2 were mixed at 15°C, the stirring rate was 450 rpm, and after stirring for 25 min, the water bath temperature was raised to 95°C, and alcohol removal was performed. The alcohol removal volume was 1 / 2 of the volume of the solution before alcohol removal. After alcohol removal, the solution was cooled to room temperature, and a crystallization regulator solution (aqueous ammonium carbonate solution) was added dropwise, the molar ratio of ammonium carbonate to tetraethyl orthosilicate in step S1 was 1:9, and the amount of water in the aqueous ammonium carbonate solution was: the volume before alcohol removal - the volume after alcohol removal. After the dropwise addition was completed, stirring was continued for 0.5 hours, and then it was transferred to a crystallization kettle, pre-crystallized at 90°C for 10 h, and then hydrothermally crystallized at 165°C for 60 h to obtain TS-1 nanocrystals.

[0124] S4, the TS-1 nanocrystals were subjected to silanization treatment with 1,2-bis(triethoxysilyl)ethane at 85°C for 4.5 h to form a bridged structure between the organosilane and the crystals. The amount of 1,2-bis(triethoxysilyl)ethane added was 0.07 of the molar amount of tetraethyl orthosilicate in step S1. Then it was hydrothermally crystallized at 165°C for 60 h to obtain TS-1 catalyst raw powder.

[0125] S5, the TS-1 catalyst raw powder was calcined at a temperature increasing rate of 2.5°C / min to 550°C for 4 h to remove the template agent, and then treated with 0.3 mol / L hydrochloric acid solution at 35°C for 1.5 h to obtain a hierarchical pore TS-1 molecular sieve.

[0126] Example 3

[0127] S1, 6 g of tetraethyl orthosilicate was added to a round-bottom flask, then an aqueous solution of template tetrapropylammonium hydroxide (25 wt%) and deionized water were added, and the mixture was stirred at 30°C and 500 rpm on a magnetic stirrer until a uniform clear solution was obtained, and then hydrolysis was carried out at 30°C for 5 h to obtain a silicon precursor solution.

[0128] The molar ratio of tetraethyl orthosilicate to tetrapropylammonium hydroxide was 1:0.2. The molar ratio of tetraethyl orthosilicate to deionized water was 1:7.

[0129] S2, at room temperature, a certain amount of isopropyl alcohol was measured into a round-bottom flask, and a certain amount of tetrabutyl titanate was slowly added dropwise, wherein the molar ratio of ethyl orthosilicate to tetrabutyl titanate was 40:1, the molar ratio of tetrabutyl titanate to isopropyl alcohol was 1:40, the dropwise addition rate was 2 seconds per drop, and the stirring rate was 500 rpm, then a certain amount of aqueous solution of tetrapropylammonium hydroxide (25 wt%) and deionized water was added, the molar ratio of tetrabutyl titanate to tetrapropylammonium hydroxide was 1:15, and the molar ratio of tetrabutyl titanate to deionized water was 1:250, to obtain a titanium precursor solution.

[0130] S3, the silicon precursor solution obtained in step S1 and the titanium precursor solution obtained in step S2 were mixed at 20°C, the stirring rate was 500 rpm, and after stirring for 30 min, the water bath temperature was raised to 90°C, and alcohol removal was performed. The alcohol removal volume was 1 / 3 of the volume of the solution before alcohol removal. After alcohol removal, the solution was cooled to room temperature, and a crystallization regulator solution (aqueous ammonium carbonate solution) was added, the molar ratio of ammonium carbonate to tetraethyl orthosilicate in step S1 was 1:10, and the amount of water in the aqueous ammonium carbonate solution was: the volume before alcohol removal - the volume after alcohol removal. After the addition was completed, stirring was continued for 0.5 hours, and then transferred to a crystallization kettle, pre-crystallized at 100°C for 15 h, and then hydrothermally crystallized at 170°C for 72 h to obtain TS-1 nanocrystals.

[0131] S4, the TS-1 nanocrystals were subjected to silanization treatment with (triethoxysilyl)cyclohexane at 90°C for 5 h to form a bridged structure between the organosilane and the crystals. The amount of (triethoxysilyl)cyclohexane added was 0.075 times the molar amount of tetraethyl orthosilicate in step S1. Then hydrothermal crystallization was carried out at 170°C for 72 h to obtain TS-1 catalyst raw powder.

[0132] S5, the TS-1 catalyst raw powder was calcined at a temperature increase rate of 3°C / min to 600°C for 6 h to remove the template, and then treated with 0.5 mol / L hydrochloric acid solution at 40°C for 2 h to obtain a hierarchical pore TS-1 molecular sieve.

[0133] Example 4

[0134] S1, 6 g of tetraethyl orthosilicate was taken into a round-bottom flask, then an aqueous solution of template agent tetrapropyl ammonium hydroxide (25 wt%) and deionized water were added, and the mixture was stirred on a magnetic stirrer at 35 °C and 550 rpm until a uniform clear solution was obtained, and then hydrolysis was carried out at 35 °C for 6 h to obtain a silicon precursor solution.

[0135] The molar ratio of tetraethyl orthosilicate to tetrapropyl ammonium hydroxide was 1:0.3. The molar ratio of tetraethyl orthosilicate to deionized water was 1:8.

[0136] S2, at room temperature, a certain amount of isopropyl alcohol was measured into a round-bottom flask, and a certain amount of tetrabutyl titanate was slowly added dropwise, wherein the molar ratio of ethyl orthosilicate to tetrabutyl titanate was 45:1, the molar ratio of tetrabutyl titanate to isopropyl alcohol was 1:45, the dropwise addition rate was 3 seconds per drop, and the stirring rate was 550 rpm, then a certain amount of aqueous solution of tetrapropyl ammonium hydroxide (25 wt%) and deionized water was added, the molar ratio of tetrabutyl titanate to tetrapropyl ammonium hydroxide was 1:17, and the molar ratio of tetrabutyl titanate to deionized water was 1:275 to obtain a titanium precursor solution.

[0137] S3, the silicon precursor solution obtained in step S1 and the titanium precursor solution obtained in step S2 were mixed at 25 °C, the stirring rate was 550 rpm, and after stirring for 35 min, the water bath temperature was raised to 95 °C, and alcohol removal was performed. The alcohol removal volume was 1 / 2 of the volume of the solution before alcohol removal. After alcohol removal, the solution was cooled to room temperature, and a crystallization regulator solution (aqueous ammonium carbonate solution) was added thereto, the molar ratio of ammonium carbonate to tetraethyl orthosilicate in step S1 was 1:11, and the amount of water in the aqueous ammonium carbonate solution was: the volume before alcohol removal - the volume after alcohol removal. After the dropwise addition was completed, stirring was continued for 0.5 h, and then transferred to a crystallization kettle, pre-crystallized at 110 °C for 20 h, and then hydrothermally crystallized at 175 °C for 84 h to obtain TS-1 nanocrystals.

[0138] S4, the TS-1 nanocrystals were mixed with 1,12-bis(triethoxysilyl)dodecane at 95 °C for 5.5 h for silanization treatment to form a bridged structure between the organosilane and the crystals. The amount of 1,12-bis(triethoxysilyl)dodecane added was 0.08 of the molar amount of tetraethyl orthosilicate in step S1. Then hydrothermal crystallization was carried out at 175 °C for 84 h to obtain TS-1 catalyst raw powder.

[0139] S5, the TS-1 catalyst raw powder was calcined at a temperature increasing rate of 2 °C / min to 650 °C for 8 h to remove the template agent, and then treated with 0.7 mol / L hydrochloric acid solution at 45 °C for 2.5 h to obtain hierarchical pore TS-1 molecular sieve.

[0140] Example 5

[0141] S1, 6 g of tetraethyl orthosilicate was taken in a round bottom flask, then the aqueous solution of template agent tetra-propyl ammonium hydroxide (25 wt%) and deionized water were added, placed on a magnetic stirrer and stirred at 40 °C and 600 rpm until a uniform clear solution was obtained, then hydrolyzed at 40 °C for 7 h to obtain a silicon precursor solution.

[0142] The molar ratio of tetraethyl orthosilicate to tetra-propyl ammonium hydroxide was 1:0.4. The molar ratio of tetraethyl orthosilicate to deionized water was 1:10.

[0143] S2, at room temperature, a certain amount of isopropyl alcohol was measured into a round bottom flask, and a certain amount of tetrabutyl titanate was slowly added dropwise, wherein the molar ratio of ethyl orthosilicate to tetrabutyl titanate was 50:1, the molar ratio of tetrabutyl titanate to isopropyl alcohol was 1:50, the dropwise addition rate was 3 seconds per drop, and the stirring rate was 600 rpm, then a certain amount of aqueous solution of tetra-propyl ammonium hydroxide (25 wt%) and deionized water was added, the molar ratio of tetrabutyl titanate to tetra-propyl ammonium hydroxide was 1:20, the molar ratio of tetrabutyl titanate to deionized water was 1:300, to obtain a titanium precursor solution.

[0144] S3, the silicon precursor solution obtained in step S1 and the titanium precursor solution obtained in step S2 were mixed at 30 °C, the stirring rate was 600 rpm, after stirring for 40 min, the water bath temperature was raised to 90 °C, and the alcohol removal operation was performed. The alcohol removal volume was 1 / 3 of the volume of the solution before alcohol removal. After alcohol removal, the solution was cooled to room temperature, and a crystallization regulator solution (ammonium carbonate aqueous solution) was added, the molar ratio of ammonium carbonate to tetraethyl orthosilicate in step S1 was 1:12, and the amount of water in the ammonium carbonate aqueous solution was: the volume before alcohol removal - the volume after alcohol removal. After the dropwise addition was completed, stirring was continued for 0.5 hours, and then transferred to a crystallization kettle, pre-crystallized at 120 °C for 24 h, and then hydrothermally crystallized at 180 °C for 96 h to obtain TS-1 nanocrystals.

[0145] S4, the TS-1 nanocrystals were subjected to silanization treatment with 1,8-bis(triethoxysilyl)octane at 100 °C for 6 h to form a bridged structure between the organosilane and the crystals. The amount of 1,8-bis(triethoxysilyl)octane added was 0.1 times the molar amount of tetraethyl orthosilicate in step S1. Then hydrothermally crystallized at 180 °C for 96 h to obtain TS-1 catalyst raw powder.

[0146] S5, the TS-1 catalyst raw powder was calcined at a temperature increasing rate of 3 °C / min to 700 °C for 10 h to remove the template agent, and then treated with 1 mol / L hydrochloric acid solution at 50 °C for 3 h to obtain a hierarchical pore TS-1 molecular sieve.

[0147] Comparative Example 1

[0148] The procedure of Example 1 was followed except that no organosilane was added in step S4.

[0149] Comparative Example 2

[0150] The procedure of Example 2 was followed except that no pre-crystallization was performed in step S3 and the mixture was directly crystallized after mixing.

[0151] Comparative Example 3

[0152] The procedure of Example 2 was followed except that no acid washing was performed in step S5.

[0153] Comparative Example 4

[0154] The procedure of Example 1 was followed except that the organosilane 1,8-bis(triethoxysilyl)octane was replaced by another organosilane tetramethylsilane.

[0155] Performance test :

[0156] (I) Catalytic performance test

[0157] The catalysts obtained in each example and comparative example were used in the reaction of naphthene oxidation and olefin epoxidation. Specifically, the prepared molecular sieve catalyst samples were subjected to experiments according to the following steps:

[0158] 1. Oxidation of cyclohexane to produce cyclohexanol and cyclohexanone:

[0159] 22.6 g of 30 wt% hydrogen peroxide and 0.1 mol of cyclohexane were added to a 100 mL reaction kettle, followed by the addition of 1.0 g of catalyst, the stirring rate was 500 rpm, and the reaction was carried out at 60°C for 4 h.

[0160] 2. Oxidation of cyclopentane to produce cyclopentanol and cyclopentanone:

[0161] 22.6 g of 30 wt% hydrogen peroxide and 0.1 mol of cyclopentane were added to a 100 mL reaction kettle, followed by the addition of 1.0 g of catalyst, the stirring rate was 500 rpm, and the reaction was carried out at 60°C for 4 h.

[0162] 3. Epoxidation of hexene to produce epoxyhexane:

[0163] 4.3 g of hexene, 11.2 g of methanol, 10.2 g of acetonitrile, 3 g of 30 wt% hydrogen peroxide solution were added to a 100 mL reaction kettle, 0.1 g of catalyst was added, the stirring rate was 500 rpm, and the reaction was carried out at 60°C for 2 h.

[0164] 4. Epoxidation of pentene to produce epoxy pentane:

[0165] Into a 100 mL autoclave, 4.3 g of pentene, 11.2 g of methanol, 10.2 g of acetonitrile, 3 g of 30 wt% hydrogen peroxide solution, 0.1 g of catalyst were added, the stirring rate was 500 rpm, and the reaction was carried out at 60°C for 2 h.

[0166] The product distribution of the obtained product was determined on an Agilent 7890A chromatograph, and the results are shown in Tables 1-2.

[0167] Conversion rate% = × 100%

[0168] Yield% = × 100%

[0169] Selectivity% = × 100%.

[0170] Table 1: Reaction effect of Experiment 1 and Experiment 2

[0171]

[0172] Table 2: Reaction effect of Experiment 3 and Experiment 4

[0173]

[0174] As can be seen from Tables 1-2, the catalytic activity of the TS-1 molecular sieve catalyst with a hierarchical pore structure prepared by the method of the present application is high, when used in the oxidation reaction of cyclopentane and cyclohexane, the conversion rate of cyclohexane reaches more than 40%, and the selectivity of cyclohexanol and cyclohexanone all reaches more than 92%; the conversion rate of cyclopentane reaches more than 35%, and the selectivity of cyclopentanol and cyclopentanone all reaches more than 90%. When used in the epoxidation reaction of hexene, the conversion rate of hexene reaches more than 31%, and the selectivity of cyclohexane all reaches more than 95%; when used in the epoxidation reaction of pentene, the conversion rate of pentene reaches more than 35%, and the selectivity of cyclohexane all reaches more than 97%. Compared with the comparative examples, it is found that the activity of the titanium-silicon molecular sieve with effective bridging is significantly improved, indicating that the titanium-silicon molecular sieve after bridging can improve the catalytic oxidation and epoxidation capacity of the titanium-silicon molecular sieve.

[0175] (II) Stability test

[0176] The catalyst was subjected to a stability test, the used catalyst after the reaction was recovered and a small amount of fresh agent was added to maintain the amount of catalyst added, and the conversion rate of the reactants and the selectivity of the products in the reaction process were analyzed to judge the cycle stability of the catalyst. Taking the oxidation of cyclohexane and the epoxidation of hexene as examples, the results are shown in Table 3.

[0177] Table 3: Catalyst stability test results

[0178]

[0179] From Table 3 above, it can be seen that the bridged TS-1 catalyst of the present application still exhibits good stability after 4 cycles, compared with the unbridged TS-1 catalyst of Comparative Example 1. Although the conversion and selectivity have a certain decline in the later stage of the reaction, the overall change is small, indicating that the catalyst has good long-term activity retention and reaction selectivity.

[0180] The principles and implementations of the present application have been described in the specific examples, and the above examples are only used to help understand the method of the present application and its core idea, including the best mode, and also enable any person skilled in the art to practice the present application, including manufacturing and using any device or system, and implementing any combined method. It should be noted that for those skilled in the art, some improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application. The scope of patent protection of the present application is defined by the claims, and can include other embodiments that can be conceived by those skilled in the art. If these other embodiments have structural elements similar to the literal expression of the claims, or if they include equivalent structural elements that are not substantially different from the literal expression of the claims, then these other embodiments should also be included within the scope of the claims.

Claims

1. A method for preparing a hierarchical-pore TS-1 molecular sieve, characterized in that, The method comprises the following steps: S1, mixing tetraethyl orthosilicate, a template agent and water to hydrolyze and obtain a silicon precursor solution; S2, mixing isopropyl alcohol, tetrabutyl titanate, a template agent and a solvent to obtain a titanium precursor solution; S3, mixing the silicon precursor solution obtained in step S1 and the titanium precursor solution obtained in step S2, removing alcohol, adding a crystallization regulator, pre-crystallizing, and crystallizing to obtain TS-1 nanocrystals; S4, mixing the TS-1 nanocrystals with an organic silane, performing silanization treatment, and then performing crystallization treatment to obtain TS-1 catalyst raw powder; S5, calcining the TS-1 catalyst raw powder to remove the template agent, and then performing acid washing to obtain a hierarchical pore TS-1 molecular sieve; The step S1 and the step S2 are not limited in sequence.

2. The production method according to claim 1, characterized by, In step S4, the organic silane is at least one of 1,8-bis(triethoxysilyl)octane, 1,2-bis(triethoxysilyl)ethane, (triethoxysilyl)cyclohexane and 1,12-bis(triethoxysilyl)dodecane.

3. The preparation method according to claim 1, characterized in that, In step S1: The template agent is tetrapropylammonium hydroxide; The molar ratio of the tetraethyl orthosilicate to the template agent is 1:(0.05-0.4). The molar ratio of the tetraethyl orthosilicate to water is 1:(4-10); The mixing temperature is 20-40 DEG C; The hydrolysis temperature is 20-40 DEG C, and the hydrolysis time is 3-7 h.

4. The method of claim 1, wherein, The molar ratio of the tetraethyl orthosilicate in step S1 to the tetrabutyl titanate in step S2 is (30-50):1; In step S2: The molar ratio of the tetrabutyl titanate to isopropyl alcohol is preferably 1:(30-50); The tetrabutyl titanate is added in the form of drops, and the drop rate is 2-3 seconds per drop; The template agent is tetrapropylammonium hydroxide; The molar ratio of the tetrabutyl titanate to the template agent is 1:(10-20); The molar ratio of the tetrabutyl titanate to water is 1:(200-300). The mixing temperature is 10-30 DEG C.

5. The preparation method according to claim 1, characterized in that, In step S3: The mixing temperature is preferably 10-20 DEG C; The alcohol removal temperature is 90-95 DEG C, and the alcohol removal volume is 1 / 3-1 / 2 of the volume of the solution before alcohol removal; The crystallization regulator is ammonium carbonate, and the molar ratio of the crystallization regulator to the tetraethyl orthosilicate in step S1 is 1:(8-12); The crystallization regulator is introduced into the system in the form of a crystallization regulator aqueous solution, and the water addition amount in the crystallization regulator aqueous solution is: the volume before alcohol removal-the volume after alcohol removal; The pre-crystallization temperature is 80-120 DEG C, and the pre-crystallization time is 6-24 h; The crystallization temperature is 160-180 DEG C, and the crystallization time is 48-96 h.

6. The method of claim 1, wherein, In step S4: The silanization treatment temperature is 80-100 DEG C, and the silanization treatment time is 4-6 h; The crystallization temperature is 160-180 DEG C, and the crystallization time is 48-96 h.

7. The preparation method according to claim 1, characterized in that, In step S5: The calcination temperature is 500-700 DEG C, and the calcination time is 2-10 h; The acid solution is a hydrochloric acid solution, and the acid washing temperature is 30-50 DEG C.

8. A hierarchical pore TS-1 molecular sieve characterized by, The method is prepared by any one of claims 1-7.

9. Use of the hierarchical-pore TS-1 molecular sieve of claim 8 in catalyzing an alkane oxidation reaction or an olefin epoxidation reaction.

10. Use according to claim 8, characterized in that, The use comprises mixing the hierarchical-pore TS-1 molecular sieve catalyst, a reactant and an oxidant to obtain a product; In the catalytic alkane oxidation reaction: The reactant used is cyclohexane or cyclopentane; The oxidant is hydrogen peroxide; the molar ratio of H2O2 to the reactant in the hydrogen peroxide is 2:1; The reaction temperature is 50-70℃ and the reaction time is 0.5-6h; In the catalytic olefin epoxidation reaction: The reactant used is pentene or hexene; The oxidant is hydrogen peroxide; the molar ratio of H2O2 to the reactant in the hydrogen peroxide is 1:(2-3.5); The catalyst is added in an amount of 0.5%-8% of the mass of the olefin; The reaction is carried out in a solvent medium; wherein the solvent is methanol and acetonitrile; The reaction temperature is 40-100℃ and the reaction time is 1-5h.

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