ZSM-5 molecular sieve, catalyst for preparing ethylbenzene through benzene alkylation and preparation and application of catalyst

Abstract

The invention discloses a ZSM-5 molecular sieve, a catalyst for preparing ethylbenzene through benzene alkylation and preparation and application of the catalyst. According to the ZSM-5 molecular sieve, the b-axis thickness is 30-100 nm, and the exposure degree of a crystal face perpendicular to the b-axis direction is 65%-75%. When the catalyst prepared from the ZSM-5 molecular sieve and used for preparing ethylbenzene through benzene alkylation is used for a reaction for preparing ethylbenzene through benzene alkylation, the ethylene conversion rate is high, the selectivity of ethyl in an alkylated product is high, and the mass content of key impurity dimethylbenzene is low.

Description

Technical Field

[0001] The invention belongs to the technical field of catalytic chemistry and chemical engineering, and in particular relates to a ZSM-5 molecular sieve, a catalyst for preparing ethylbenzene by alkylation of benzene, and a preparation method and application thereof. Background Art

[0002] Benzene alkylation products, such as ethylbenzene, are important basic organic raw materials with a wide range of uses and play an important role in the development of the national economy.

[0003] The raw materials of the technology of alkylation of benzene and ethylene to produce ethylbenzene come from a wide range of sources. The ethylene source can be pure ethylene, dilute ethylene or ethanol, among which the dilute ethylene raw material is cheap. At present, the dilute ethylene raw material mainly comes from the tail gas of FCC and DCC units, in which the mass concentration of ethylene is generally 10%-30%. In order to alleviate the shortage of dilute ethylene raw materials and create more economic benefits, it is particularly important to develop the technology of using crude ethane cracking gas as dilute ethylene raw material and benzene alkylation to produce ethylbenzene.

[0004] However, the mass concentration of ethylene in crude ethane cracking gas is high (up to more than 40%), and a significant increase in ethylene concentration will bring significant problems. Since the alkylation of benzene and ethylene is a highly exothermic reaction, the reaction of benzene and high-concentration dilute ethylene will cause the temperature rise of the alkylation reactor to increase significantly, increase the probability of side reactions and the rate of coking, and significantly increase the content of key impurities xylene in the ethylbenzene product, and significantly shorten the service life of the catalyst. The key to the technology of alkylation of benzene and crude ethane cracking gas to produce ethylbenzene is to develop an alkylation catalyst with high activity, high selectivity and high stability. The active component of the catalyst for the gas-phase alkylation of benzene and ethylene to produce ethylbenzene is generally ZSM-5 molecular sieve.

[0005] CN101993331A discloses a method for preparing ethylbenzene by alkylation of pure ethylene or dry gas with benzene. The method adopts a fixed bed reactor loaded with at least one section of ZSM-5 molecular sieve catalyst I with a SiO2 / Al2O3 molar ratio of 50-150, and at least one section of ZSM-5 molecular sieve catalyst II with a SiO2 / Al2O3 molar ratio of 160-300; 30%-70% of pure ethylene or dry gas enters the bed loaded with catalyst I, and the remaining pure ethylene or dry gas enters the bed loaded with catalyst II; 80%-100% of benzene enters the first section of the bed loaded with catalyst I from the top of the reactor, and the remaining benzene enters the catalyst beds below in sections, so as to control the difference between the inlet temperature of each section of the catalyst bed and the inlet temperature of the logistics at the top of the reactor to not exceed ±5°C. The process flow adopted by the method is complicated, and it is also necessary to use a variety of catalysts for mixed loading, and strict control.

[0006] CN102875316A discloses a method for preparing ethylbenzene by alkylation of dry gas and benzene. The method adopts dry gas and benzene as reaction raw materials, and the reaction raw materials contact with a catalyst to produce ethylbenzene by gas phase alkylation reaction; the catalyst used contains the following components by weight percentage: a) 40%-90% of ZSM-5 molecular sieve with a grain diameter of 5-500 nanometers and a silicon-aluminum molar ratio SiO2 / Al2O3 of 30-400; b) 9%-59% of a binder alumina or silicon dioxide; c) 0.1%-10% of alkaline earth metal oxide and 0.1%-10% of rare earth metal oxide; the molded catalyst is treated with high-temperature steam, and then dried and calcined to obtain a finished catalyst. The catalyst is a catalyst developed for preparing ethylbenzene by alkylation of dry gas and benzene with low ethylene concentration. For ethylene raw materials with high ethylene concentration, especially under reaction conditions with low benzene-olefin ratio, its activity, selectivity and stability need to be further improved. Summary of the invention

[0007] The present invention provides a ZSM-5 molecular sieve, a catalyst for preparing ethylbenzene by alkylation of benzene, and a preparation method and application thereof. The ZSM-5 molecular sieve of the present invention is a novel ZSM-5 molecular sieve. The molecular sieve of the present invention is used as a catalyst for preparing ethylbenzene by alkylation of benzene, and can improve the ethylene conversion rate, improve the ethyl selectivity in the alkylation product, inhibit side reactions, reduce the xylene content, and extend the service life of the catalyst.

[0008] In a first aspect, the present invention provides a ZSM-5 molecular sieve, wherein the b-axis thickness of the molecular sieve is 50-100 nm, and the exposure of the crystal plane perpendicular to the b-axis direction is 65%-75%, preferably 69%-71%.

[0009] In the above technical solution, preferably, the static water initial contact angle of the molecular sieve is in the range of 120-160°.

[0010] In the above technical solution, preferably, the infrared spectrum of the molecular sieve is between 680-760cm -1 There are two strong peaks.

[0011] In the above technical solution, the ZSM-5 molecular sieve has a SiO2:Al2O3 molar ratio of 100-300.

[0012] In the above technical scheme, the schematic chemical composition of the molecular sieve in the synthesized state, in terms of moles, includes: SiO2: nAl2O3: mR2: xR3, wherein R2 is organic II, R3 is organic III, n is 0.0033-0.01, m is 0.0015-0.005, and x is 0.005-0.1. The synthesized state of the molecular sieve refers to the uncalcined state. When the molecular sieve exists in the synthesized state, it may also contain a template and water. The template is one or more of tetrapropylammonium bromide, tetrapropylammonium hydroxide, ethylamine, ethylenediamine, n-propylamine, propylenediamine, n-butylamine, butylene diamine, n-hexylamine, hexamethylenediamine, ammonia water, hexamethyleneimine, piperidine, and piperazine. The molar ratio of the template to SiO2 is 0.05-0.3. The molar ratio of water to SiO2 is 3-20.

[0013] In the above technical solution, the structural formula of the organic substance II is Wherein R1-R3 are each independently selected from methoxy, ethoxy or 3-methoxypropyl, and R4 and R5 are each independently selected from hydrogen, methyl, ethyl, N-aminomethyl or N-aminoethyl.

[0014] In the above technical solution, the structural formula of the organic compound III is Wherein R1-R6 are each independently selected from methyl, ethyl, propyl or phenyl, and the number of R1-R6 that are simultaneously phenyl is 1-4.

[0015] The second aspect of the present invention provides a method for preparing the above-mentioned ZSM-5 molecular sieve, comprising:

[0016] (a) mixing a silicon source I, an aluminum source I, water, an organic matter I and an organic matter II to obtain a mixture A;

[0017] (b) treating mixture A to obtain mixture B;

[0018] (c) mixing mixture B, silicon source II, aluminum source II, water, template and organic matter III to obtain mixture C;

[0019] (d) After the mixture C is crystallized, liquid-solid separation, washing and drying are performed to obtain the molecular sieve.

[0020] In the above technical solution, preferably, step (a) has one or more of the following characteristics:

[0021] In the above technical solution, preferably, in step (a), the silicon source I is one or more of tetramethyl silicate, tetraethyl silicate, tetrapropyl silicate, tetrabutyl silicate, and tetraphenyl silicate;

[0022] In the above technical solution, preferably, in step (a), the aluminum source I is one or more of aluminum sulfate, aluminum isopropoxide, sodium aluminate, and pseudo-boehmite;

[0023] In the above technical scheme, preferably, in step (a), the organic substance I is one or more of tetrapropylammonium hydroxide, ethylamine, ethylenediamine, n-butylamine, butanediamine, hexamethyleneimine, and piperidine;

[0024] In the above technical solution, preferably, the structural formula of the organic substance II in step (a) is Wherein R1-R3 are each independently selected from methoxy, ethoxy or 3-methoxypropyl, and R4 and R5 are each independently selected from hydrogen, methyl, ethyl, N-aminomethyl or N-aminoethyl.

[0025] In the above technical scheme, preferably, in step (a), the molar ratios of silicon source I, aluminum source I, water, organic matter I and organic matter II are silicon source I: aluminum source I: water: organic matter I: organic matter II = 1: (0-0.02): (5-20): (0.1-1): (0.05-0.3), wherein silicon source I and aluminum source I are calculated as SiO2 and Al2O3, respectively.

[0026] In the above technical solution, preferably, the treatment in step (b) is carried out under closed conditions with stirring at 60-130° C. for 1-72 hours.

[0027] In the above technical solution, preferably, step (c) has one or more of the following characteristics:

[0028] In the above technical solution, preferably, in step (c), the silicon source II is one or more of silica sol, white carbon black, silicon powder, tetramethyl silicate, tetraethyl silicate, tetrapropyl silicate, tetrabutyl silicate and tetraphenyl silicate;

[0029] In the above technical solution, preferably, in step (c), the aluminum source II is one or more of aluminum nitrate, aluminum chloride, aluminum sulfate, aluminum isopropoxide, sodium aluminate, and pseudo-boehmite;

[0030] In the above technical scheme, preferably, in step (c), the template agent is one or more of tetrapropylammonium bromide, tetrapropylammonium hydroxide, ethylamine, ethylenediamine, n-propylamine, propylenediamine, n-butylamine, butylenediamine, n-hexylamine, hexamethylenediamine, ammonia water, hexamethyleneimine, piperidine, and piperazine;

[0031] In the above technical solution, preferably, the structural formula of the organic compound III in step (c) is Wherein R1-R6 are each independently selected from methyl, ethyl, propyl or phenyl, and the number of R1-R6 that are simultaneously phenyl is 1-4.

[0032] In the above technical scheme, preferably, in step (c), the molar ratios of silicon source II, aluminum source II, water, template and organic matter III are respectively silicon source II: aluminum source II: water: template: organic matter III = 1: (0.0033-0.01): (8-20): (0.1-0.3): (0.01-0.10), and the ratio of the mass of the mixture B to the total mass of the five substances of silicon source II, aluminum source II, water, template and organic matter III is (0.05-0.2): 1, wherein the silicon source II and the aluminum source II are calculated as SiO2 and Al2O3, respectively.

[0033] In the above technical solution, preferably, step (d) has one or more of the following characteristics:

[0034] In the above technical solution, preferably, the crystallization conditions in step (d) are crystallization at 110-170° C. for 6-72 hours under closed conditions;

[0035] In the above technical solution, preferably, the liquid-solid separation in step (d) is carried out by filter paper filtration, centrifugation or plate and frame filter pressing, etc.; the washing condition is to wash the solid obtained by liquid-solid separation with deionized water for multiple times until the pH value of the washing liquid is 7-8. The drying condition is to dry at 100-200°C for 5-12 hours.

[0036] The third aspect of the present invention provides a catalyst for preparing ethylbenzene by alkylation of benzene, wherein the catalyst comprises a ZSM-5 molecular sieve, and the ZSM-5 molecular sieve is derived from the molecular sieve provided in the first aspect or the molecular sieve prepared by the method of the second aspect.

[0037] In the above technical solution, in the catalyst, the ZSM-5 molecular sieve exists in a calcined state.

[0038] In the above technical solution, the catalyst, in addition to the molecular sieve, optionally includes aluminum oxide, silicon oxide or a mixture thereof.

[0039] In the above technical solution, preferably, the molecular sieve catalyst has a molecular sieve content of more than 80%, preferably 80%-90%, and an alumina content of less than 20%, preferably 10%-20%, based on the mass of the catalyst.

[0040] In the above technical solution, preferably, the micropore volume of the catalyst is 0.13-0.17 cm 3 ·g -1 , the mesopore volume is 0.50-0.80cm 3 ·g -1 , mechanical strength is 50-120N / cm, bulk density is 0.50-0.60g·cm -3 .

[0041] A fourth aspect of the present invention provides a method for preparing a catalyst for preparing ethylbenzene by alkylation of benzene, comprising:

[0042] (e) mixing at least one of the molecular sieves described in the first aspect and the molecular sieve prepared in the second aspect, alumina and a polymer mixture, and then forming the mixture, followed by drying, calcining, ammonium exchange, steam treatment and acid washing to obtain the catalyst.

[0043] In the above technical solution, preferably, step (e) has one or more of the following characteristics:

[0044] In the above technical solution, preferably, the aluminum oxide in step (e) is preferably aluminum oxide monohydrate;

[0045] In the above technical solution, preferably, in step (e), the polymer mixture is a mixture of starch and at least one substance selected from cetyltrimethylammonium bromide, P123 or F127, wherein the mass ratio of starch to the polymer mixture is 55%-70%;

[0046] In the above technical solution, preferably, in step (e), the mass ratio of molecular sieve E, alumina and polymer mixture is: molecular sieve E: alumina: polymer mixture = 1: (0.1-0.4): (0.03-0.2);

[0047] In the above technical solution, preferably, a molding aid may be added in step (e), such as at least one of a peptizing acid (such as dilute nitric acid) and an extrusion aid (such as sesbania powder);

[0048] In the above technical solution, preferably, the dilute nitric acid in step (e) is preferably an aqueous solution of nitric acid, with a mass concentration of 3%-10%;

[0049] In the above technical solution, preferably, in step (e), the mass ratio of molecular sieve E, dilute nitric acid, and sesbania powder is: molecular sieve E: dilute nitric acid: sesbania powder = 1: (0.5-1.2): (0.01-0.05);

[0050] In the above technical solution, preferably, the molding in step (e) is preferably extrusion molding, followed by drying, roasting, ammonium exchange, steam, and acid washing;

[0051] In the above technical scheme, preferably, in step (e), the forming shape is cylindrical, clover-shaped, four-leaf clover-shaped, gear-shaped, etc.; the drying condition is 100-200° C. for 5-12 hours; the roasting condition is 500-600° C. for 4-10 hours; the ammonium exchange condition is using an ammonium salt solution with a mass concentration of 2%-10% for 1-10 hours at 20-80° C., and continuously exchanging 2-5 times, and the ammonium salt is one of ammonium sulfate, ammonium chloride, ammonium acetate or ammonium nitrate; the water vapor treatment condition is 300-450° C. for 4-10 hours in a saturated water vapor atmosphere; the pickling condition is using an acid solution with a mass concentration of 0.1%-3.0% for 1-10 hours at 20-80° C., and the acid is at least one of hydrochloric acid, sulfuric acid, nitric acid or oxalic acid.

[0052] The fifth aspect of the present invention provides a catalyst for producing ethylbenzene by alkylation of benzene prepared by the method of the fourth aspect.

[0053] In the above technical solution, preferably, the molecular sieve catalyst has a molecular sieve content of more than 80%, preferably 80%-90%, and an alumina content of less than 20%, preferably 10%-20%, based on the mass of the catalyst.

[0054] In the above technical solution, preferably, the micropore volume of the catalyst is 0.13-0.17 cm 3 ·g -1 , the mesopore volume is 0.50-0.80cm 3 ·g -1 , mechanical strength is 50-120N / cm, bulk density is 0.50-0.60g·cm -3 .

[0055] A sixth aspect of the present invention provides a method for preparing ethylbenzene by alkylation of benzene, wherein the reaction raw materials benzene and ethylene are contacted with the above-mentioned catalyst to generate ethylbenzene.

[0056] In the above technical solution, preferably, the mass concentration of ethylene in the ethylene raw material is 10%-100%.

[0057] In the above technical solution, preferably, the reaction temperature is 320-380°C, the reaction pressure is 0.5-2.6MPa, and the ethylene mass space velocity is 0.2-1.0h -1 , the molar ratio of benzene to ethylene is 4.0-6.0.

[0058] Compared with the prior art, the present invention has the following beneficial effects:

[0059] 1. The inventor of the present invention has found through research that the b-axis thickness of ZSM-5 molecular sieve and the exposure of the crystal plane perpendicular to the b-axis direction are crucial to the performance of the benzene alkylation catalyst. Since the crystal growth process of ZSM-5 molecular sieve follows the Ostwald-ripening and Wulff Construction rules, the ZSM-5 molecular sieve prepared by conventional methods is mostly coffin morphology, and the b-axis thickness and the exposure of the crystal plane perpendicular to the b-axis direction are difficult to control. The inventor has further found that in the process of preparing the molecular sieve, organic matter II and organic matter III are introduced at different times, so that the b-axis thickness of the molecular sieve can be effectively controlled to be 50-100nm and the exposure of the crystal plane perpendicular to the b-axis direction can be 65%-75%, preferably 69%-71%. The present invention provides a new ZSM-5 molecular sieve. The ZSM-5 molecular sieve of the present invention is used in the reaction of benzene alkylation to ethylbenzene, which can significantly help to improve the ethylene conversion rate, inhibit side reactions, reduce the content of key impurity xylene, and extend the service life of the catalyst, and is particularly suitable for the reaction of benzene alkylation to ethylbenzene.

[0060] 2. Due to the introduction of organic matter II and organic matter III, the initial static water contact angle of the ZSM-5 molecular sieve of the present invention is in the range of 120-160°, and the molecular sieve contains phenyl, and its infrared spectrum is 680-760cm -1 During the molding process, the condensation between the binder and the silanol groups on the surface of the molecular sieve can be effectively inhibited, the pore blocking effect of the binder can be reduced, and the comprehensive performance of the catalyst can be improved.

[0061] 3. In the preparation process of the catalyst of the present invention, not only a specific molecular sieve is used, but also a polymer mixture is added during the molding process, which reduces the blockage of the molecular sieve micropores by the binder. The obtained catalyst has higher micropore volume and mesopore volume, as well as suitable mechanical strength and suitable bulk density characteristics. In the reaction process, the diffusion performance of the reaction molecules is further improved, which is beneficial to improving the ethylene conversion rate, inhibiting side reactions, reducing the xylene content, and extending the life of the catalyst. It is particularly suitable for industrial benzene and high ethylene concentration mixed carbon dialkylation to produce ethylbenzene reaction device.

[0062] 4. Compared with the tail gas of the previous FCC and DCC devices, the mass concentration of ethylene in the crude ethane cracking gas is as high as 40% or more. Since the alkylation of benzene and ethylene is a strong exothermic reaction, the reaction of benzene and high-concentration dilute ethylene will cause the temperature rise of the alkylation reactor to increase significantly, increase the probability of side reactions and the rate of coking, and significantly increase the content of key impurity xylene in the ethylbenzene product, and greatly shorten the service life of the catalyst. The catalyst of the present invention is particularly suitable for preparing ethylbenzene by reacting mixed carbon dioxide with high ethylene concentration as a raw material with benzene. Under the reaction conditions of high ethylene mass concentration and low molar ratio of benzene and ethylene, the ethylene conversion rate is greater than 99.8%, the ethyl selectivity in the alkylation product is greater than 99.4%, and the mass content of key impurity xylene is less than 600ppm.

[0063] 5. The method of the present invention can use high ethylene concentration mixed carbon dioxide as raw material, which can expand the source of dilute ethylene raw materials, alleviate the shortage of dilute ethylene raw materials, and create more economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 The XRD spectrum of the molecular sieve prepared in Example 1 of the present invention;

[0065] Figure 2 This is a SEM photo of the molecular sieve prepared in Example 1 of the present invention;

[0066] Figure 3 This is a photograph of the static water initial contact angle of the molecular sieve prepared in Example 1 of the present invention;

[0067] Figure 4 This is the infrared spectrum of the molecular sieve prepared in Example 1 of the present invention;

[0068] Figure 5 XRD spectrum of the molecular sieve prepared in Comparative Example 1 of the present invention;

[0069] Figure 6 This is a SEM photograph of the molecular sieve prepared in Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0070] The present invention is described in detail below in conjunction with specific implementation modes, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0071] The b-axis thickness of the molecular sieve and the exposure of the crystal plane perpendicular to the b-axis direction in the present invention are obtained by analyzing SEM photos, and the SEM photos are obtained using a Hitachi S-4800 cold field emission high-resolution scanning electron microscope produced by Hitachi. Among them, the exposure of the crystal plane perpendicular to the b-axis direction is the ratio of the area of ​​the ZSM-5 molecular sieve 010 crystal plane to the total area of ​​all crystal planes.

[0072] In the present invention, the micropore volume and the mesopore volume are obtained by nitrogen adsorption-desorption test. The nitrogen adsorption-desorption isotherm of the catalyst is tested at liquid nitrogen temperature using a BEL-MAX specific surface area and pore size analyzer produced by BELSORP Co., Ltd. of Japan. The total pore volume is calculated using the BET equation, and the micropore volume is calculated using the t-plot method. The difference between the total pore volume and the micropore volume is the mesopore volume.

[0073] In the present invention, the mechanical strength is obtained by using an intelligent particle strength tester. The DLIII type intelligent particle strength tester of Dalian Penghui Technology Development Co., Ltd. is used to test the mechanical strength of the catalyst. The length of the measured catalyst is 5 mm, and it is placed horizontally on the tester to test the maximum pressure that the catalyst can withstand when it is broken. After testing the crushing strength of 20 catalysts, the average value is taken.

[0074] In the present invention, the XRD spectrum of the catalyst was obtained by using the Ultima IV X-ray powder diffractometer produced by Rigaku Corporation of Japan. The voltage was selected as 35 kV, the current was selected as 30 mA, and the scanning speed was 1°·min -1 .

[0075] In the present invention, the bulk density of the catalyst is calculated by dividing the actual weight of the added catalyst (unit: g) by the actual volume using a 1000 mL graduated cylinder as the container, and the unit is g·cm -3 .

[0076] In the present invention, the SiO2 / Al2O3 molar ratio is obtained by ICP testing, and the ICP test is performed using a Kontron Model S-35 ICP-AES analyzer to obtain silicon-aluminum ratio data.

[0077] In the present invention, a Chengde Dingsheng JY-82C video contact angle tester is used to test and obtain the static water initial contact angle of the molecular sieve, an appropriate amount of ground powder sample is placed on a tablet press to be pressed into a sheet, and then placed on a contact angle test platform, water drops are dripped on the automatic titration system of the equipment, test photos are taken, and then the angle of the contact angle is measured by the angle measurement method.

[0078] The structure of the molecular sieve was characterized by an iS50 infrared spectrometer from Thermo Scientific, USA, using KBr pellets with a wave number range of 400-4000 cm -1 .

[0079] [Example 1]

[0080] This embodiment is used to synthesize a catalyst for alkylation of benzene to ethylbenzene, and the specific preparation process is as follows:

[0081] 208.3 g of tetraethyl silicate, 3.33 g of aluminum sulfate 18hydrate, 180 g of water, 101.68 g of tetrapropylammonium hydroxide and 19.13 g of the structural formula (wherein R1 is a methoxy group, R2 and R3 are ethoxy groups, and R4 and R5 are hydrogen atoms) and organic matter II are uniformly mixed to obtain a mixture A1, wherein tetraethyl silicate is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: tetrapropylammonium hydroxide: organic matter II = 1: 0.005: 10: 0.5: 0.1 (molar ratio). Mixture A1 is stirred at 110°C for 36 hours in a sealed container to obtain mixture B1. 26.6 grams of mixture B1, 60 grams of silicon powder, 3.33 grams of aluminum sulfate 18hydrate, 180 grams of water, 9.02 grams of ethylamine and 14.25 grams of the structural formula (wherein R1 and R4 are phenyl groups, and R2, R3, R5 and R6 are methyl groups) and organic matter III are contacted to obtain a mixture C1, wherein silicon powder is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: ethylamine: organic matter III = 1: 0.005: 10: 0.2: 0.05 (molar ratio). C1 is crystallized at 150°C for 48 hours in a sealed container to obtain a mixture D1, which is then centrifuged to obtain a solid, which is washed with deionized water for multiple times until the pH of the washing liquid reaches 7.5, and then the washed solid is dried at 150°C for 10 hours to obtain a molecular sieve E1.

[0082] 50 g of E1, 15 g of alumina monohydrate, 30 g of 5% nitric acid aqueous solution, 1.5 g of sesbania powder and 5 g of a polymer mixture (including 3 g of starch and 2 g of hexadecyltrimethylammonium bromide) were mixed and extruded into a cylindrical shape, and then treated at 150° C. for 8 hours; 550° C. for 6 hours; treated with 5% ammonium sulfate solution at 50° C. for 6 hours, and exchanged 4 times continuously; treated at 400° C. in a saturated water vapor atmosphere for 6 hours; treated with 0.5% hydrochloric acid solution at 40° C. for 5 hours to obtain catalyst F1.

[0083] The XRD spectrum of molecular sieve E1 is as follows Figure 1 As shown, it has typical ZSM-5 molecular sieve diffraction peaks. The SEM photo of molecular sieve E1 is shown in Figure 2 As shown, the b-axis thickness of the molecular sieve is 90nm, and the exposure of the crystal plane perpendicular to the b-axis direction is 70%. The SiO2 / Al2O3 molar ratio of the molecular sieve E1 is 200. The static water initial contact angle test results of the molecular sieve E1 are shown in Figure 3 The infrared spectrum of molecular sieve E1 is shown in Figure 4 As shown, at 680-760cm -1 There are two strong peaks.

[0084] Through testing, the micropore volume of catalyst F1 is 0.14 cm 3 ·g -1 , the mesopore volume is 0.64 cm 3 ·g -1 , mechanical strength is 110N / cm, bulk density is 0.54g·cm -3 .

[0085] [Example 2]

[0086] This embodiment is used to synthesize a catalyst for alkylation of benzene to ethylbenzene, and the specific preparation process is as follows:

[0087] 152.2 g of tetramethyl silicate, 2.66 g of aluminum sulfate 18-hydrate, 360 g of water, 73.1 g of n-butylamine and 70.8 g of the structural formula (wherein R1 and R2 are methoxyl groups, R3 is ethoxyl group, R4 is N-aminoethyl group, and R5 is a hydrogen atom) and organic matter II are uniformly mixed to obtain mixture A2, wherein tetramethyl silicate is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: n-butylamine: organic matter II = 1:0.004:20:1:0.3 (molar ratio). Mixture A2 is stirred at 130°C for 1 hour in a sealed container to obtain mixture B2. 101 g of mixture B2, 60 g of white carbon black, 0.408 g of pseudo-boehmite, 360 g of water, 61 g of tetrapropylammonium hydroxide and 38.9 g of the structural formula (wherein R1-R3 are phenyl groups, and R4-R6 are ethyl groups) and an organic substance III are contacted to obtain a mixture C2, wherein white carbon is calculated as SiO2: pseudo-boehmite is calculated as Al2O3: water: tetrapropylammonium hydroxide: organic substance III = 1: 0.004: 20: 0.3: 0.1 (molar ratio). C2 is crystallized at 170°C in a sealed container for 6 hours to obtain a mixture D2, which is then centrifuged to obtain a solid, which is washed with deionized water for multiple times until the pH of the washing liquid reaches 7.5, and then the washed solid is dried at 200°C for 5 hours to obtain a molecular sieve E2.

[0088] 50 g of E2, 20 g of alumina monohydrate, 60 g of 3% nitric acid aqueous solution, 2.5 g of sesbania powder and 10 g of a polymer mixture (including 7 g of starch and 3 g of P123) were mixed and extruded into a four-leaf clover shape, and then treated at 200°C for 5 hours; 600°C for 4 hours; treated with 10% ammonium chloride solution at 80°C for 1 hour, and exchanged 4 times continuously; treated at 450°C in a saturated water vapor atmosphere for 4 hours; treated with 3% hydrochloric acid solution at 80°C for 1 hour to obtain catalyst F2.

[0089] Molecular sieve E2 has typical ZSM-5 molecular sieve diffraction peaks as characterized by XRD. The b-axis thickness of molecular sieve E2 is 60nm, and the exposure of the crystal plane perpendicular to the b-axis is 71%. The SiO2 / Al2O3 molar ratio of molecular sieve E2 is 250. The static water initial contact angle value of molecular sieve E2 is 154°. The infrared spectrum of molecular sieve E2 is 680-760cm -1 There are two strong peaks.

[0090] Through testing, the micropore volume of catalyst F2 is 0.16cm 3 ·g -1 , the mesopore volume is 0.81cm 3 ·g -1 , mechanical strength is 96N / cm, bulk density is 0.51g·cm -3 .

[0091] [Example 3]

[0092] This embodiment is used to synthesize a catalyst for alkylation of benzene to ethylbenzene, and the specific preparation process is as follows:

[0093] 208.3 g of tetraethyl silicate, 2.20 g of aluminum sulfate 18-hydrate, 90 g of water, 20.34 g of tetrapropylammonium hydroxide and 16.05 g of the structural formula (wherein R1 is methoxy, R2 is ethoxy, R3 is 3-methoxypropyl, R4 and R5 are methyl) and organic matter II are uniformly mixed to obtain mixture A3, wherein tetraethyl silicate is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: tetrapropylammonium hydroxide: organic matter II = 1: 0.0033: 5: 0.1: 0.05 (molar ratio). Mixture A3 is stirred at 60°C for 72 hours in a sealed container to obtain mixture B3. 18.23 g of mixture B3, 208.3 g of tetraethyl silicate, 2.20 g of aluminum sulfate 18hydrate, 144 g of water, 7.34 g of n-butylamine and 4.09 g of the structural formula (wherein R1, R2, R4 and R5 are phenyl groups, and R3 and R6 are methyl groups) and an organic substance III are contacted to obtain a mixture C3, wherein tetraethyl silicate is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: n-butylamine: organic substance III = 1: 0.0033: 8: 0.1: 0.01 (molar ratio). C3 is crystallized in a sealed container at 110°C for 72 hours to obtain a mixture D3, which is then centrifuged to obtain a solid, which is washed with deionized water for multiple times until the pH of the washing solution reaches 7.5, and then the washed solid is dried at 100°C for 12 hours to obtain a molecular sieve E3.

[0094] 50 g of E3, 5 g of alumina monohydrate, 25 g of 3% nitric acid aqueous solution, 0.5 g of sesbania powder and 1.5 g of a polymer mixture (including 0.825 g of starch and 0.675 g of F127) were mixed and extruded into a four-leaf clover shape, and then treated at 100°C for 12 hours; 500°C for 10 hours; treated with 2% ammonium acetate solution at 20°C for 10 hours, and exchanged 4 times in succession; treated at 300°C in a saturated water vapor atmosphere for 10 hours; treated with 0.1% oxalic acid solution at 20°C for 10 hours to obtain catalyst F3.

[0095] Molecular sieve E3 has typical ZSM-5 molecular sieve diffraction peaks as characterized by XRD. The b-axis thickness of molecular sieve E3 is 95nm, and the exposure of the crystal plane perpendicular to the b-axis is 69%. The SiO2 / Al2O3 molar ratio of molecular sieve E3 is 302. The static water initial contact angle value of molecular sieve E3 is 121°. The infrared spectrum of molecular sieve E3 is 680-760cm -1 There are two strong peaks.

[0096] Through testing, the micropore volume of catalyst F3 is 0.13cm 3 ·g -1 , the mesopore volume is 0.52cm 3 ·g -1 , mechanical strength is 104N / cm, bulk density is 0.58g·cm -3 .

[0097] [Example 4]

[0098] This embodiment is used to synthesize a catalyst for alkylation of benzene to ethylbenzene, and the specific preparation process is as follows:

[0099] 208.3 g of tetraethyl silicate, 180 g of water, 101.68 g of tetrapropylammonium hydroxide and 19.13 g of the structural formula (wherein R1 is a methoxy group, R2 and R3 are ethoxy groups, and R4 and R5 are hydrogen atoms) and organic matter II are uniformly mixed to obtain a mixture A4, wherein tetraethyl silicate is calculated as SiO2: water: tetrapropylammonium hydroxide: organic matter II = 1:10:0.5:0.1 (molar ratio). Mixture A4 is stirred at 110°C for 36 hours in a sealed container to obtain mixture B4. 26.6 grams of mixture B4, 60 grams of silicon powder, 3.33 grams of aluminum sulfate 18hydrate, 180 grams of water, 9.02 grams of ethylamine and 14.25 grams of the structural formula (wherein R1 and R4 are phenyl groups, and R2, R3, R5 and R6 are methyl groups) and an organic substance III are contacted to obtain a mixture C4, wherein silicon powder is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: ethylamine: organic substance III = 1: 0.005: 10: 0.2: 0.05 (molar ratio). C4 is crystallized in a sealed container at 150°C for 48 hours to obtain a mixture D4, which is then centrifuged to obtain a solid, which is washed with deionized water for multiple times until the pH of the washing liquid reaches 7.5, and then the washed solid is dried at 150°C for 10 hours to obtain a molecular sieve E4.

[0100] 50 g of E4, 15 g of alumina monohydrate, 30 g of 5% nitric acid aqueous solution, 1.5 g of sesbania powder and 5 g of a polymer mixture (including 3 g of starch and 2 g of hexadecyltrimethylammonium bromide) were mixed and extruded into a cylindrical shape, and then treated at 150° C. for 8 hours; 550° C. for 6 hours; treated with 5% ammonium sulfate solution at 50° C. for 6 hours, and exchanged 4 times continuously; treated at 400° C. in a saturated water vapor atmosphere for 6 hours; treated with 0.5% hydrochloric acid solution at 40° C. for 5 hours to obtain catalyst F4.

[0101] Molecular sieve E4 has typical ZSM-5 molecular sieve diffraction peaks as characterized by XRD. The b-axis thickness of molecular sieve E4 is 85nm, and the exposure of the crystal plane perpendicular to the b-axis is 71%. The SiO2 / Al2O3 molar ratio of molecular sieve E4 is 202. The static water initial contact angle value of molecular sieve E4 is 133°. The infrared spectrum of molecular sieve E2 is 680-760cm -1 There are two strong peaks.

[0102] Through testing, the micropore volume of catalyst F4 is 0.14cm 3 ·g -1 , the mesopore volume is 0.65cm 3 ·g -1 , mechanical strength is 106N / cm, bulk density is 0.54g·cm -3 .

[0103] [Comparative Example 1]

[0104] Compared with Example 1, the only difference is that: no addition of the structural formula (wherein R1 is a methoxy group, R2 and R3 are ethoxy groups, and R4 and R5 are hydrogen atoms) organic substance II, the specific preparation process of the catalyst is as follows:

[0105] 208.3 g of tetraethyl silicate, 3.33 g of aluminum sulfate 18hydrate, 180 g of water and 101.68 g of tetrapropylammonium hydroxide were mixed to obtain mixture A5, wherein tetraethyl silicate was calculated as SiO2: aluminum sulfate 18hydrate was calculated as Al2O3: water: tetrapropylammonium hydroxide = 1:0.005:10:0.5 (molar ratio). Mixture A5 was stirred at 110°C for 36 hours in a sealed container to obtain mixture B5. 26.6 g of mixture B5, 60 g of silicon powder, 3.33 g of aluminum sulfate 18hydrate, 180 g of water, 9.02 g of ethylamine and 14.25 g of the structural formula (wherein R1 and R4 are phenyl groups, and R2, R3, R5 and R6 are methyl groups) and organic matter III are contacted to obtain a mixture C5, wherein silicon powder is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: ethylamine: organic matter III = 1: 0.005: 10: 0.2: 0.05 (molar ratio). C5 is crystallized at 150°C for 48 hours in a sealed container to obtain a mixture D5, which is then centrifuged to obtain a solid, which is washed with deionized water for multiple times until the pH of the washing liquid reaches 7.5, and then the washed solid is dried at 150°C for 10 hours to obtain a molecular sieve E5.

[0106] 50 g of E5, 15 g of alumina monohydrate, 30 g of 5% nitric acid aqueous solution, 1.5 g of sesbania powder and 5 g of a polymer mixture (including 3 g of starch and 2 g of hexadecyltrimethylammonium bromide) were mixed and extruded into a cylindrical shape, and then treated at 150° C. for 8 hours; 550° C. for 6 hours; treated with 5% ammonium sulfate solution at 50° C. for 6 hours, and exchanged 4 times continuously; treated at 400° C. in a saturated water vapor atmosphere for 6 hours; treated with 0.5% hydrochloric acid solution at 40° C. for 5 hours to obtain catalyst F5.

[0107] The XRD spectrum of molecular sieve E5 is as follows Figure 5 As shown, it has typical ZSM-5 molecular sieve diffraction peaks. The SEM photo of molecular sieve E5 is shown in Figure 6 As shown, the b-axis thickness of the molecular sieve is 160nm, and the exposure of the crystal plane perpendicular to the b-axis direction is 61%. The SiO2 / Al2O3 molar ratio of the molecular sieve E5 is 202. The static water initial contact angle value of the molecular sieve E5 is 138°. The infrared spectrum of the molecular sieve E2 is at 680-760cm -1 There are two strong peaks.

[0108] Through testing, the micropore volume of catalyst F5 is 0.13cm 3 ·g -1 , the mesopore volume is 0.58 cm 3 ·g -1 , mechanical strength is 107N / cm, bulk density is 0.55g·cm-3 .

[0109] [Comparative Example 2]

[0110] Compared with Example 1, the only difference is that: no addition of the structural formula (wherein R1 and R4 are phenyl groups, and R2, R3, R5 and R6 are methyl groups) organic compound III, the specific preparation process of the catalyst is as follows:

[0111] 208.3 g of tetraethyl silicate, 3.33 g of aluminum sulfate 18hydrate, 180 g of water, 101.68 g of tetrapropylammonium hydroxide and 19.13 g of the structural formula (wherein R1 is a methoxy group, R2 and R3 are ethoxy groups, and R4 and R5 are hydrogen atoms) and organic matter II are uniformly mixed to obtain a mixture A6, wherein tetraethyl silicate is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: tetrapropylammonium hydroxide: organic matter II = 1: 0.005: 10: 0.5: 0.1 (molar ratio). Mixture A6 is stirred at 110° C. for 36 hours in a sealed container to obtain a mixture B6. 26.6 g of mixture B6, 60 g of silicon powder, 3.33 g of aluminum sulfate 18hydrate, 180 g of water and 9.02 g of ethylamine are contacted to obtain a mixture C6, wherein silicon powder is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: ethylamine = 1: 0.005: 10: 0.2 (molar ratio). C6 was crystallized at 150° C. for 48 hours in a sealed container to obtain a mixture D6, which was then centrifuged to obtain a solid, which was washed with deionized water for multiple times until the pH of the washing solution reached 7.5, and then the washed solid was dried at 150° C. for 10 hours to obtain the molecular sieve E6.

[0112] 50 g of E6, 15 g of alumina monohydrate, 30 g of 5% nitric acid aqueous solution, 1.5 g of sesbania powder and 5 g of a polymer mixture (including 3 g of starch and 2 g of hexadecyltrimethylammonium bromide) were mixed and extruded into a cylindrical shape, and then treated at 150° C. for 8 hours; 550° C. for 6 hours; treated with 5% ammonium sulfate solution at 50° C. for 6 hours, and exchanged 4 times continuously; treated at 400° C. in a saturated water vapor atmosphere for 6 hours; treated with 0.5% hydrochloric acid solution at 40° C. for 5 hours to obtain catalyst F6.

[0113] Molecular sieve E6 has typical ZSM-5 molecular sieve diffraction peaks as characterized by XRD. The b-axis thickness of molecular sieve E6 is 185nm, and the exposure of the crystal plane perpendicular to the b-axis is 61%. The SiO2 / Al2O3 molar ratio of molecular sieve E6 is 201. The static water initial contact angle of molecular sieve E6 is 43°. The infrared spectrum of molecular sieve E6 is 680-760cm -1 There are no two strong peaks.

[0114] Through testing, the micropore volume of catalyst F6 is 0.13cm 3 ·g -1 , the mesopore volume is 0.58 cm 3 ·g -1 , mechanical strength is 110N / cm, bulk density is 0.55g·cm -3 .

[0115] [Comparative Example 3]

[0116] Compared with Example 1, the only difference is that organic matter II and organic matter III are added at the same time.

[0117] 208.3 g of tetraethyl silicate, 3.33 g of aluminum sulfate 18hydrate, 180 g of water and 101.68 g of tetrapropylammonium hydroxide were mixed to obtain a mixture A7, wherein the molar ratio of tetraethyl silicate as SiO2: aluminum sulfate 18hydrate as Al2O3: water: tetrapropylammonium hydroxide = 1:0.005:10:0.5). Mixture A7 was stirred at 110°C for 36 h in a sealed container to obtain mixture B7. 26.6 g of mixture B7, 60 g of silicon powder, 3.33 g of aluminum sulfate 18hydrate, 180 g of water, 9.02 g of ethylamine, 0.995 g of the structural formula (wherein R1 is a methoxy group, R2 and R3 are ethoxy groups, and R4 and R5 are hydrogen atoms) and 14.25 grams of organic compound II with the structural formula (wherein R1 and R4 are phenyl groups, and R2, R3, R5 and R6 are methyl groups) and organic matter III are contacted to obtain a mixture C7, wherein silicon powder is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: ethylamine: organic matter III = 1: 0.005: 10: 0.2: 0.05 (molar ratio). C7 is crystallized at 150°C in a sealed container for 48 hours to obtain a mixture D7, which is then centrifuged to obtain a solid, which is washed with deionized water for multiple times until the pH of the washing liquid reaches 7.5, and then the washed solid is dried at 150°C for 10 hours to obtain a molecular sieve E7.

[0118] 50 g of E7, 15 g of alumina monohydrate, 30 g of 5% nitric acid aqueous solution, 1.5 g of sesbania powder and 5 g of a polymer mixture (including 3 g of starch and 2 g of hexadecyltrimethylammonium bromide) were mixed and extruded into a cylindrical shape, and then treated at 150° C. for 8 hours; 550° C. for 6 hours; treated with 5% ammonium sulfate solution at 50° C. for 6 hours, and exchanged 4 times continuously; treated at 400° C. in a saturated water vapor atmosphere for 6 hours; treated with 0.5% hydrochloric acid solution at 40° C. for 5 hours to obtain catalyst F7.

[0119] Molecular sieve E7 has typical ZSM-5 molecular sieve diffraction peaks as characterized by XRD. The b-axis thickness of molecular sieve E7 is 155nm, and the exposure of the crystal plane perpendicular to the b-axis is 62%. The SiO2 / Al2O3 molar ratio of molecular sieve E7 is 202. The static water initial contact angle of molecular sieve E7 is 140°. The infrared spectrum of molecular sieve E7 is at 680-760cm -1 There are two strong peaks.

[0120] Through testing, the micropore volume of catalyst F7 is 0.13cm 3 ·g -1 , the mesopore volume is 0.60cm 3 ·g -1 , mechanical strength is 103N / cm, bulk density is 0.55g·cm -3 .

[0121] [Comparative Example 4]

[0122] Compared with Example 1, the only difference is that the equimolar structural formula is (wherein R1 is a methoxy group, R2 and R3 are ethoxy groups, and R4 and R5 are hydrogen atoms) the alternative structural formula of the organic compound II is (wherein R1 and R4 are phenyl groups, and R2, R3, R5 and R6 are methyl groups) an organic compound III.

[0123] 208.3 g of tetraethyl silicate, 3.33 g of aluminum sulfate 18hydrate, 180 g of water, 101.68 g of tetrapropylammonium hydroxide and 19.13 g of the structural formula (wherein R1 is a methoxy group, R2 and R3 are ethoxy groups, and R4 and R5 are hydrogen atoms) and organic matter II are uniformly mixed to obtain a mixture A8, wherein tetraethyl silicate is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: tetrapropylammonium hydroxide: organic matter II = 1: 0.005: 10: 0.5: 0.1 (molar ratio). Mixture A8 is stirred at 110°C for 36 hours in a sealed container to obtain mixture B8. 26.6 grams of mixture B8, 60 grams of silicon powder, 3.33 grams of aluminum sulfate 18hydrate, 180 grams of water, 9.02 grams of ethylamine and 9.57 grams of the structural formula (wherein R1 is a methoxy group, R2 and R3 are ethoxy groups, and R4 and R5 are hydrogen atoms) and an organic substance II are contacted to obtain a mixture C8, wherein silicon powder is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: ethylamine: organic substance II = 1: 0.005: 10: 0.2: 0.05 (molar ratio). C8 is crystallized in a sealed container at 150°C for 48 hours to obtain a mixture D8, which is then centrifuged to obtain a solid, which is washed with deionized water for multiple times until the pH of the washing liquid reaches 7.5, and then the washed solid is dried at 150°C for 10 hours to obtain a molecular sieve E8.

[0124] 50 g of E8, 15 g of alumina monohydrate, 30 g of 5% nitric acid aqueous solution, 1.5 g of sesbania powder and 5 g of a polymer mixture (including 3 g of starch and 2 g of hexadecyltrimethylammonium bromide) were mixed and extruded into a cylindrical shape, and then treated at 150° C. for 8 hours; 550° C. for 6 hours; treated with 5% ammonium sulfate solution at 50° C. for 6 hours, and exchanged 4 times continuously; treated at 400° C. in a saturated water vapor atmosphere for 6 hours; treated with 0.5% hydrochloric acid solution at 40° C. for 5 hours to obtain catalyst F8.

[0125] Molecular sieve E8 has typical ZSM-5 molecular sieve diffraction peaks as characterized by XRD. The b-axis thickness of molecular sieve E8 is 146nm, and the exposure of the crystal plane perpendicular to the b-axis is 62%. The SiO2 / Al2O3 molar ratio of molecular sieve E8 is 201. The static water initial contact angle of molecular sieve E8 is 82°. The infrared spectrum of molecular sieve E8 is at 680-760cm -1 There are no two strong peaks.

[0126] Through testing, the micropore volume of catalyst F8 is 0.14cm 3 ·g -1 , the mesopore volume is 0.61cm 3 ·g -1 , mechanical strength is 102N / cm, bulk density is 0.55g·cm -3 .

[0127] [Comparative Example 5]

[0128] Compared with Example 1, the only difference is that the equimolar structural formula is (wherein R1 and R4 are phenyl groups, and R2, R3, R5 and R6 are methyl groups) the alternative structural formula of the organic compound III is (wherein R1 is a methoxy group, R2 and R3 are ethoxy groups, and R4 and R5 are hydrogen atoms) an organic substance II.

[0129] 208.3 g of tetraethyl silicate, 3.33 g of aluminum sulfate 18hydrate, 180 g of water, 101.68 g of tetrapropylammonium hydroxide and 28.5 g of the structural formula (wherein R1 and R4 are phenyl groups, and R2, R3, R5 and R6 are methyl groups) and organic matter III are uniformly mixed to obtain mixture A9, wherein tetraethyl silicate is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: tetrapropylammonium hydroxide: organic matter III = 1: 0.005: 10: 0.5: 0.1 (molar ratio). Mixture A9 is stirred at 110°C for 36 hours in a sealed container to obtain mixture B9. 26.6 grams of mixture B9, 60 grams of silicon powder, 3.33 grams of aluminum sulfate 18hydrate, 180 grams of water, 9.02 grams of ethylamine and 14.25 grams of the structural formula (wherein R1 and R4 are phenyl groups, and R2, R3, R5 and R6 are methyl groups) and organic matter III are contacted to obtain a mixture C9, wherein silicon powder is calculated as SiO2: aluminum sulfate 18hydrate is calculated as Al2O3: water: ethylamine: organic matter III = 1: 0.005: 10: 0.2: 0.05 (molar ratio). C9 is crystallized at 150°C in a sealed container for 48 hours to obtain a mixture D9, which is then centrifuged to obtain a solid, which is washed with deionized water for multiple times until the pH of the washing liquid reaches 7.5, and then the washed solid is dried at 150°C for 10 hours to obtain a molecular sieve E9.

[0130] 50 g of E9, 15 g of alumina monohydrate, 30 g of 5% nitric acid aqueous solution, 1.5 g of sesbania powder and 5 g of a polymer mixture (including 3 g of starch and 2 g of hexadecyltrimethylammonium bromide) were mixed and extruded into a cylindrical shape, and then treated at 150° C. for 8 hours; 550° C. for 6 hours; treated with 5% ammonium sulfate solution at 50° C. for 6 hours, and exchanged 4 times continuously; treated at 400° C. in a saturated water vapor atmosphere for 6 hours; treated with 0.5% hydrochloric acid solution at 40° C. for 5 hours to obtain catalyst F9.

[0131] Molecular sieve E9 has typical ZSM-5 molecular sieve diffraction peaks as characterized by XRD. The b-axis thickness of molecular sieve E9 is 150nm, and the exposure of the crystal plane perpendicular to the b-axis is 62%. The SiO2 / Al2O3 molar ratio of molecular sieve E9 is 201. The static water initial contact angle of molecular sieve E9 is 152°. The infrared spectrum of molecular sieve E9 is 680-760cm -1 There are two strong peaks.

[0132] Through testing, the micropore volume of catalyst F9 is 0.13cm 3 ·g -1 , the mesopore volume is 0.61cm 3 ·g -1 , mechanical strength is 106N / cm, bulk density is 0.55g·cm -3 .

[0133] [Examples 5-8]

[0134] Catalysts F1-F4 prepared in Examples 1-4 were respectively applied to the alkylation of benzene to produce ethylbenzene, wherein the ethylene mass concentration was 50%, the reaction temperature was 340°C, the pressure was 2.2 MPa, and the ethylene mass space velocity was 0.8 h -1 , under the condition that the molar ratio of benzene to ethylene was 4.5, the ethylene conversion rate, the ethyl selectivity in the alkylation product and the content of the key impurity xylene were tested. The test results are shown in Table 1 below.

[0135] [Comparative Examples 6-10]

[0136] Catalysts F5-F9 prepared in Comparative Examples 1-5 were respectively applied to the alkylation of benzene to produce ethylbenzene, wherein the ethylene mass concentration was 50%, the reaction temperature was 340°C, the pressure was 2.2 MPa, and the ethylene mass space velocity was 0.8 h -1 , under the condition that the molar ratio of benzene to ethylene was 4.5, the ethylene conversion rate, the ethyl selectivity in the alkylation product and the content of the key impurity xylene were tested. The test results are shown in Table 1 below.

[0137] Table 1 Benzene alkylation reaction results for ethylbenzene

[0138]

[0139] [Examples 9-12]

[0140] Catalysts F1-F4 prepared in Examples 1-4 were tested for their one-way life in the alkylation of benzene to ethylbenzene reaction under ultra-high ethylene mass space velocity reaction conditions, wherein the ethylene mass concentration was 50%, the reaction temperature was 340°C, the pressure was 2.2 MPa, and the ethylene mass space velocity was 10 h -1 The test was conducted under the condition that the molar ratio of benzene to ethylene was 4.5. The single-pass life refers to the time from the start of the reaction to the time when the ethylene conversion rate drops to 40% of the initial conversion rate. The test results are shown in Table 2 below.

[0141] [Comparative Examples 11-15]

[0142] The catalysts F5-F9 prepared in Examples 1-5 were tested for their one-way life in the reaction of benzene alkylation to ethylbenzene under ultra-high ethylene mass space velocity reaction conditions, wherein the ethylene mass concentration was 50%, the reaction temperature was 340°C, the pressure was 2.2 MPa, and the ethylene mass space velocity was 10 h -1 , tested under the condition of benzene and ethylene molar ratio of 4.5, one-way life refers to the time from the start of the reaction to the time when the ethylene conversion rate drops to 40% of the initial conversion rate. The test results are shown in Table 2 below. Under ultra-high ethylene space velocity reaction conditions, the one-way life of catalysts F1-F4 is significantly longer than that of catalysts F5-F9.

[0143] Table 2 Single-pass life test results of catalysts under ultra-high space velocity reaction conditions

[0144] Catalyst No. One-way life, h F1 388 F2 372 F3 366 F4 382 F5 243 F6 258 F7 246 F8 243 F9 258

[0145] The above describes the specific implementation of the present invention in detail, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the various technical features being combined in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A ZSM-5 molecular sieve, characterized in that: In the molecular sieve, the b-axis thickness is 30-100 nm, preferably 50-90 nm, and the exposure degree of the crystal plane perpendicular to the b-axis direction is 65%-75%, preferably 69%-71%.

2. The molecular sieve according to claim 1, characterized in that: The static water initial contact angle of the molecular sieve is in the range of 120-160°.

3. The molecular sieve according to claim 1 or 2, characterized in that: The infrared spectrum of the molecular sieve is between 680 and 760 cm -1 There are two strong peaks.

4. The molecular sieve according to claim 1, characterized in that: The SiO2 / Al2O3 molar ratio of the molecular sieve is 100-300.

5. The method for preparing the ZSM-5 molecular sieve according to any one of claims 1 to 4, comprising: (a) mixing a silicon source I, an optional aluminum source I, water, an organic substance I and an organic substance II to obtain a mixture A; (b) treating mixture A to obtain mixture B; (c) mixing mixture B, silicon source II, aluminum source II, water, template and organic matter III to obtain mixture C; (d) After the mixture C is crystallized, liquid-solid separation, washing and drying are performed to obtain the molecular sieve.

6. The preparation method according to claim 5, characterized in that: In step (a), the organic substance I is one or more of tetrapropylammonium hydroxide, ethylamine, ethylenediamine, n-butylamine, butanediamine, hexamethyleneimine, and piperidine; And / or, the structural formula of organic substance II in step (a) is wherein R1-R3 are each independently selected from methoxy, ethoxy or 3-methoxypropyl, and R4 and R5 are each independently selected from hydrogen, methyl, ethyl, N-aminomethyl or N-aminoethyl; And / or, the structural formula of the organic compound III in step (c) is Wherein R1-R6 are each independently selected from methyl, ethyl, propyl or phenyl, and the number of R1-R6 that are simultaneously phenyl is 1-4.

7. The preparation method according to claim 5 or 6, characterized in that: In step (a), the silicon source I is one or more of tetramethyl silicate, tetraethyl silicate, tetrapropyl silicate, tetrabutyl silicate, and tetraphenyl silicate; and / or, in step (a), the aluminum source I is one or more of aluminum sulfate, aluminum isopropoxide, sodium aluminate, and pseudo-boehmite; Preferably, in step (a), the molar ratios of silicon source I, aluminum source I, water, organic matter I and organic matter II are respectively silicon source I: aluminum source I: water: organic matter I: organic matter II = 1: (0-0.02): (5-20): (0.1-1.0): (0.05-0.3), wherein silicon source I and aluminum source I are calculated as SiO2 and Al2O3, respectively.

8. The preparation method according to claim 5 or 6, characterized in that: The treatment in step (b) is carried out under closed conditions at 60-130° C. with stirring for 1-72 hours; and / or the crystallization conditions in step (d) are carried out under closed conditions at 110-170° C. for 6-72 hours.

9. The preparation method according to claim 5 or 6, characterized in that: In step (c), the silicon source II is one or more of silica sol, white carbon black, silicon powder, tetramethyl silicate, tetraethyl silicate, tetrapropyl silicate, tetrabutyl silicate, and tetraphenyl silicate; and / or, the aluminum source II in step (c) is one or more of aluminum nitrate, aluminum chloride, aluminum sulfate, aluminum isopropoxide, sodium aluminate, and pseudo-boehmite; and / or, the template in step (c) is one or more of tetrapropylammonium bromide, tetrapropylammonium hydroxide, ethylamine, ethylenediamine, n-propylamine, propylenediamine, n-butylamine, butanediamine, n-hexylamine, hexamethylenediamine, ammonia water, hexamethyleneimine, piperidine, and piperazine; Preferably, in step (c), the molar ratios of silicon source II, aluminum source II, water, template and organic matter III are respectively silicon source II: aluminum source II: water: template: organic matter III = 1: (0.0033-0.010): (8-20): (0.1-0.3): (0.01-0.10), and the ratio of the mass of the mixture B to the total mass of the five substances of silicon source II, aluminum source II, water, template and organic matter III is (0.05-0.2): 1, wherein the silicon source II and the aluminum source II are calculated as SiO2 and Al2O3, respectively.

10. A catalyst for preparing ethylbenzene by alkylation of benzene, characterized in that: The catalyst comprises the molecular sieve according to any one of claims 1 to 4 or the molecular sieve prepared by the method according to any one of claims 5 to 9, and optionally comprises aluminum oxide.

11. The catalyst according to claim 10, characterized in that The catalyst has a molecular sieve content of more than 80%, preferably 80%-90%, and an alumina content of less than 20%, preferably 10%-20%, based on the mass of the catalyst.

12. The catalyst according to claim 10, characterized in that The micropore volume of the catalyst is 0.13-0.17 cm 3 ·g -1 , the mesopore volume is 0.50-0.80cm 3 ·g -1 , mechanical strength is 50-120N / cm, bulk density is 0.50-0.60g·cm -3 .

13. A method for preparing a catalyst for preparing ethylbenzene by alkylation of benzene, comprising: (e) mixing at least one of the molecular sieves described in any one of claims 1 to 4 and the molecular sieves prepared by the method described in any one of claims 5 to 9, alumina and a polymer mixture, and then forming the mixture, drying, calcining, ammonium exchange, steam treatment and acid washing to obtain the catalyst.

14. The preparation method according to claim 13, characterized in that: The alumina in step (e) is alumina monohydrate; and / or the polymer mixture in step (e) is a mixture of starch and at least one substance selected from cetyltrimethylammonium bromide, P123 or F127, wherein the mass ratio of starch to the polymer mixture is 55%-70%; Preferably, in step (e), the mass ratio of molecular sieve E, alumina and polymer mixture is: molecular sieve E: alumina: polymer mixture = 1: (0.1-0.4): (0.03-0.2); Preferably, in step (e), the drying condition is 100-200°C for 5-12 hours; the roasting condition is 500-600°C for 4-10 hours; and the steam treatment condition is 300-450°C for 4-10 hours in a saturated steam atmosphere.

15. A method for preparing ethylbenzene by alkylation of benzene, characterized in that: The reaction raw materials benzene and ethylene are contacted with the catalyst described in any one of claims 10-12 or the catalyst prepared by the method described in any one of claims 13-14 to generate ethylbenzene.

16. The method according to claim 15, characterized in that The ethylene mass concentration in the ethylene feedstock is 10%-100%; and / or, the reaction conditions are as follows: the reaction temperature is 320-380°C, the reaction pressure is 0.5-2.6MPa, and the ethylene mass space velocity is 0.2-1.0h -1 , the molar ratio of benzene to ethylene is 4.0-6.0.

Images