Preparation method of MOR type titanium silicalite molecular sieve for improving catalytic performance by introducing DDS

Abstract

The present invention relates to the preparation technology of molecular sieve catalysts, aiming to provide a preparation method of MOR-type titanium silicate molecular sieve with improved catalytic performance by introducing DDS. The method includes: using a silicon source, an aluminum source, potassium hydroxide, water, and dimethyldimethoxysilane DDS as an additive as raw materials, mixing them evenly to obtain a gel precursor; then successively carrying out hydrothermal crystallization reaction, ammonium exchange, acid treatment for dealumination, and titanium supplementation by gas-solid phase method, and finally obtaining Ti-MOR molecular sieve. In the preparation process of Ti-MOR in the present invention, no organic template agent is used, which has little environmental pollution; using the additive DDS for modification in the synthesis of MOR precursor can significantly improve the catalytic performance of the obtained Ti-MOR.

Description

Technical Field

[0001] The present invention belongs to the technical field of molecular sieve catalyst preparation, and particularly relates to a preparation method of MOR-type titanium silicalite for improving catalytic performance by introducing dimethyldimethoxysilane (DDS). Background Art

[0002] Zeolite molecular sieve is a special porous inorganic material, named because the pore diameter and structure inside it can screen molecules. Zeolite molecular sieves not only have a specific pore structure, but also adjustable acid properties, large pore volume, high specific surface area and good hydrothermal and chemical stability. They are widely used as adsorbents, ion exchangers and catalysts in industrial production.

[0003] Since the transition metal element Ti was successfully introduced into the pure silica zeolite framework, researchers successfully prepared titanium silicalite TS-1 with MFI topological structure. The TS-1 / H2O2 system was found to perform well in many selective oxidation processes such as alcohol oxidation, phenol hydroxylation, olefin epoxidation, and ketone ammoximation, being green and environmentally friendly with high product selectivity. Due to its wide use in the chemical industry, TS-1 has gradually become one of the most representative heteroatom molecular sieves. With the maturity of the artificial zeolite synthesis technology, titanium silicalites with other topological structures have also been synthesized successively, obtaining heteroatom molecular sieves with new catalytic characteristics. Various types of titanium silicalites can be divided into microporous structures such as TS-1, Ti-Beta, Ti-MOR, ITQ-7, Ti-MWW and mesoporous structures such as Ti-MCM-41, Ti-SBA-15 and Ti-HMS according to the pore size.

[0004] Among them, for the synthesis of MOR-type titanium silicalite, the problem with the traditional hydrothermal method of directly introducing titanium is that the high alkalinity and high aluminum concentration required in the synthesis process of MOR itself greatly affect the state and content of titanium species in the in-situ hydrothermally synthesized titanium-containing mordenite, making its catalytic performance unsatisfactory; the presence of framework aluminum species exacerbates the ineffective decomposition of hydrogen peroxide on the catalyst, further affecting the catalytic activity of the catalyst, and the synthesis system of high-silica mordenite often has higher costs and complexity.

[0005] Therefore, Kraushar et al. first proposed a method of implanting heteroatom Ti through the post-treatment of MOR-type molecular sieves: the first step is to acid-treat the MOR precursor, and the second step is to implant titanium atoms through a gas-phase method using TiCl4 as the Ti source or a liquid-phase method using (NH4)2TiF6 as the Ti source, respectively. Compared with the direct synthesis method, the precursor MOR of the post-treatment synthesis method can be synthesized by a structure-directing agent-free method, which can greatly reduce the production cost and avoid the environmental pollution problem caused by calcining to remove the structure-directing agent; acid treatment can controllably remove aluminum species, effectively inhibit the formation of non-framework Ti, and more effectively implant titanium into the molecular sieve framework. The post-treatment method is currently the main way to prepare highly active Ti-MOR molecular sieves.

[0006] However, for MOR synthesized under certain specific systems as the parent body, the catalytic performance of the Ti-MOR molecular sieve prepared by the post-treatment method is not satisfactory, and there is still room for improvement. Preparing MOR-type titanium silicate molecules with higher catalytic activity has always been a key research issue in the scientific and industrial communities.

[0007] Therefore, it is necessary to propose new catalyst modification technologies to solve the above problems. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to overcome the deficiencies in the prior art and provide a preparation method of MOR-type titanium silicate molecular sieve with improved catalytic performance by introducing DDS.

[0009] To solve the technical problem, the solution of the present invention is:

[0010] Provide a preparation method of MOR-type titanium silicate molecular sieve with improved catalytic performance by introducing DDS, including the following steps:

[0011] (1) Take a silicon source, an aluminum source, potassium hydroxide, water, and dimethyldimethoxysilane DDS as an additive, mix and stir evenly at room temperature to obtain a gel precursor for synthesizing the Ti-MOR molecular sieve precursor;

[0012] Control the addition amounts of each raw material so that the molar ratio of SiO2:Al2O3:KOH:additive:H2O in the gel precursor is 1:0.042 - 0.083:0.53 - 0.78:0.05 - 0.20:12 - 20;

[0013] (2) Load the gel precursor and an appropriate amount of MOR seeds into a hydrothermal crystallization synthesis kettle for crystallization reaction; after the reaction is completed, wash and dry the separated solid to obtain a K + type MOR precursor powder;

[0014] (3) Mix the K + type MOR precursor powder with an appropriate amount of ammonium chloride solution for ammonium exchange; repeat the ammonium exchange three times, and after washing, drying, and calcination, obtain H + type MOR;

[0015] (4) Mix the H + type MOR with nitric acid for acid treatment to remove a part of aluminum in the framework; wash to neutrality and then perform drying and calcination to obtain a dealuminated MOR precursor with defect sites;

[0016] (5) Place the dealuminated MOR precursor in a quartz tube, first pretreat it with flowing hot nitrogen; then pass heated TiCl4 carried by flowing nitrogen through the dealuminated MOR precursor to achieve contact, and implant titanium atoms into the dealuminated MOR precursor through a gas-solid phase reaction; wash the MOR precursor powder with titanium supplementation to neutrality, and after drying and calcination, obtain Ti-MOR zeolite.

[0017] As a preferred embodiment of the present invention, in the step (1), the aluminum source is aluminum sulfate octadecahydrate; the silicon source is silica sol with a solid content of 40%, and this ratio is in mass percentage.

[0018] As a preferred embodiment of the present invention, in the step (1), the stirring time during mixing at room temperature is 2 hours.

[0019] As a preferred embodiment of the present invention, in the step (2), the mass ratio of the MOR seed crystal to SiO2 in the gel precursor is 1:200; the crystallization reaction temperature is 180 °C and the time is 96 h.

[0020] As a preferred embodiment of the present invention, in the step (3), the concentration of the ammonium chloride solution is 1 - 1.5 mol / L, the solid-liquid ratio of the MOR precursor powder to the ammonium chloride solution is 1:100, the ammonium exchange temperature is 80 °C, and when the sodium oxide content in 0.01 g of the molecular sieve is ≤ 1000 ppm, it is considered that the ammonium exchange is completed; the drying temperature after ammonium exchange is 80 °C until it is dried; the calcination temperature is 550 - 600 °C and the time is 6 - 10 h.

[0021] As a preferred embodiment of the present invention, in the step (4), the concentration of nitric acid is 6 - 10 mol / L, the solid-liquid ratio of MOR to nitric acid is 1:20, the acid treatment time is 20 hours, and the temperature is 80 °C; the drying temperature is 80 °C until it is dried; the calcination temperature is 550 - 600 °C and the time is 4 - 8 h.

[0022] As a preferred embodiment of the present invention, in the step (4), when the silicon-aluminum ratio of the dealuminated sample is lower than 50, repeat the operation of acid treatment for dealumination until the silicon-aluminum ratio of the sample is greater than or equal to 50.

[0023] As a preferred embodiment of the present invention, in step (5), TiCl4 is placed in a bubbling flask and heated, and nitrogen gas is passed through the bubbling flask to carry TiCl4 into the quartz tube; the flow rate of nitrogen gas is controlled to be 30 - 60 mL / min, and the heating temperature of TiCl4 in the bubbling flask is 40°C - 80°C.

[0024] As a preferred embodiment of the present invention, in step (5), the temperature of the gas-solid phase reaction in the quartz tube is controlled to be 400 - 550°C, and the time is 6 - 15 h; the temperature during calcination is 550°C - 600°C, and the time is 4 - 8 h.

[0025] Description of the invention principle:

[0026] In the gas-solid phase preparation of MOR-type titanium silicalite molecular sieve, the activity of the molecular sieve catalyst is affected not only by conditions such as the flow rate of nitrogen gas, treatment time, and temperature during titanium supplementation, but also by the synthesis conditions of the parent body, modification treatment, and pretreatment conditions, which have a more crucial impact on the creation of defect sites in the framework and ultimately affect the activity of the prepared Ti-MOR catalyst. Many scholars have conducted a large number of explorations on the titanium supplementation conditions in the post-treatment method and found the optimal titanium supplementation conditions and processes applicable to the current industry. However, there is still a gap in the exploration of the impact of the synthesis conditions of the MOR parent body itself on the activity of the finally prepared Ti-MOR catalyst, such as the selection of silicon source / aluminum source / alkali source during the MOR synthesis process, whether to use a template agent, and the modification of MOR, etc.

[0027] Therefore, it is necessary to design the titanium-supplemented MOR parent body to obtain more and more effective titanium supplementation defect sites. Starting from this, the present invention proposes to add a class of organosilanes represented by dimethyldimethoxysilane (DDS) during the hydrothermal synthesis process of MOR raw powder, which can introduce a considerable amount of methyl groups into MOR. After calcination, the methyl groups are converted into hydroxyl groups or hydroxyl nests. And the hydroxyl groups or hydroxyl nests are the key to gas-solid phase titanium supplementation, which is beneficial to the implantation of titanium during the subsequent titanium supplementation process; at the same time, the molecular sieve rich in hydroxyl groups has better hydrophilicity and can better enrich H2O2. Through the above innovative preparation route, the purpose of effectively improving the catalytic performance of MOR-type titanium silicalite molecular sieve is finally achieved.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] 1. In the preparation process of Ti-MOR in the present invention, no organic template agent is used, which has little environmental pollution.

[0030] 2. Using the additive DDS for modification in the synthesis of the MOR precursor can significantly improve the catalytic performance of the obtained Ti-MOR. Description of the drawings

[0031] Figure 1 XRD pattern of the titanium silicalite molecular sieve prepared in Example 1 of the present invention.

[0032] Figure 2 FT-IR spectrum of the hydrogen-type molecular sieve prepared in Example 1 of the present invention.

[0033] Figure 3 FT-IR spectrum of the molecular sieve after dealumination prepared in Example 1 of the present invention.

[0034] Figure 4 FT-IR spectrum of the titanium silicalite molecular sieve prepared in Example 1 of the present invention.

[0035] Figure 5 XRD pattern of the as-synthesized molecular sieve powder synthesized in Comparative Example 1.

[0036] Figure 6 XRD pattern of the molecular sieve after dealumination prepared in Comparative Example 1.

[0037] Figure 7 XRD pattern of the titanium silicalite molecular sieve prepared in Comparative Example 1.

[0038] Figure 8 FT-IR spectrum of the hydrogen-type molecular sieve prepared in Comparative Example 1.

[0039] Figure 9 FT-IR spectrum of the molecular sieve after dealumination prepared in Comparative Example 1.

[0040] Figure 10 FT-IR spectrum of the titanium silicalite molecular sieve prepared in Comparative Example 1. Detailed implementation manners

[0041] The technical solutions and effects of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners, but the protection scope of the present invention is not limited thereto.

[0042] First part: Technical solutions of the present invention

[0043] The preparation method of the MOR-type titanium silicalite molecular sieve for improving catalytic performance by introducing DDS provided by the present invention includes the following steps:

[0044] (1) Take a silicon source, an aluminum source, potassium hydroxide, water, and dimethyldimethoxysilane DDS as an additive, mix and stir evenly at room temperature to obtain a gel precursor for synthesizing the Ti-MOR molecular sieve precursor;

[0045] Control the addition amounts of various raw materials so that the molar ratio of SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor is 1 : 0.042 - 0.083 : 0.53 - 0.78 : 0.05 - 0.20 : 12 - 20; optionally, the aluminum source is aluminum sulfate octadecahydrate; the silicon source is silica sol with a solid content of 40%, and this ratio is in mass percentage; the stirring time during mixing at room temperature is 2 hours.

[0046] (2) Load the gel precursor and an appropriate amount of MOR seeds into a hydrothermal crystallization synthesis autoclave for crystallization reaction; the mass ratio of MOR seeds to SiO2 in the gel precursor is 1:200; the temperature of the crystallization reaction is 180 °C and the time is 96 h; after the reaction is completed, wash and dry the separated solid to obtain the K + - type MOR precursor powder;

[0047] (3) Mix the K + - type MOR precursor powder with an appropriate amount of ammonium chloride solution for ammonium exchange; repeat the ammonium exchange three times, and consider the ammonium exchange completed when the sodium oxide content in 0.01 g of molecular sieve is ≤ 1000 ppm; after washing, drying, and calcination treatments, obtain H + - type MOR; optionally, the concentration of the ammonium chloride solution is 1 - 1.5 mol / L, the solid - liquid ratio of the MOR precursor powder to the ammonium chloride solution is 1:100, the ammonium exchange temperature is 80 °C; the drying temperature is 80 °C until dried; the calcination temperature is 550 - 600 °C and the time is 6 - 10 h.

[0048] (4) Mix the H + - type MOR with nitric acid for acid treatment to remove a part of the aluminum in the framework; after washing to neutrality, perform drying and calcination treatments to obtain a dealuminated MOR precursor with defect sites; when the silicon - aluminum ratio of the dealuminated sample is lower than 50, repeat the acid treatment for aluminum removal until the silicon - aluminum ratio of the sample is greater than or equal to 50. Optionally, the concentration of nitric acid is 6 - 10 mol / L, the solid - liquid ratio of MOR to nitric acid is 1:20, the acid treatment time is 20 hours, and the temperature is 80 °C; the drying temperature is 80 °C until dried; the calcination temperature is 550 - 600 °C and the time is 4 - 8 h.

[0049] (5) Place the dealuminated MOR precursor in a quartz tube, and first pretreat it with flowing hot nitrogen; then allow flowing nitrogen to carry the heated TiCl4 to flow through the dealuminated MOR precursor to achieve contact. Specifically, place TiCl4 in a bubbling flask and heat it to enable nitrogen to pass through the bubbling flask and carry TiCl4 into the quartz tube; control the flow rate of nitrogen to be 30 - 60 mL / min, and the heating temperature of TiCl4 in the bubbling flask to be 40°C - 80°C. Implant titanium atoms into the dealuminated MOR precursor through a gas-solid phase reaction. Wash the MOR precursor powder after titanium supplementation to neutrality, and after drying and calcination treatment, obtain the Ti-MOR molecular sieve. Optionally, control the temperature of the gas-solid phase reaction in the quartz tube to be 400 - 550°C, and the time to be 6 - 15 h; the temperature during calcination is 550°C - 600°C, and the time is 4 - 8 h.

[0050] Part Two: Examples and Comparative Examples

[0051] Example 1:

[0052] At room temperature, mix aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water, and stir for 2 hours to obtain a gel precursor for synthesizing the molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor = 1 : 0.042 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, load them into a hydrothermal crystallization synthesis kettle together, and raise the temperature to 180°C to cause a crystallization reaction for 96 h. After cooling, wash and dry to obtain MOR raw powder. Perform ammonium exchange treatment on it three times with 1 mol / L ammonium chloride solution at 80°C, with a solid-liquid ratio of 1:100. After washing again and drying at 80°C, calcine at 550°C for 6 h to obtain H-MOR. Treat the sample obtained in the above steps with 8 mol / L nitric acid at 80°C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80°C, then calcine at 550°C for 4 h to obtain dealuminated MOR; if the silicon-aluminum ratio of the dealuminated sample is lower than 50, the operation of acid treatment for removing aluminum should be repeated until the silicon-aluminum ratio of the sample is greater than or equal to 50 (the same applies hereinafter). Place the sample obtained in the above steps in a quartz tube, perform pretreatment at 500°C for 2 h under a nitrogen purge of 30 ml / min, then contact with TiCl4 heated to 60°C at 550°C for 6 h, and finally purge with nitrogen for 2 h. The obtained sample is washed and dried, and then calcined at 550°C for 4 h to obtain Ti-MOR.

[0053] The XRD pattern of Ti-MOR is as Figure 1 shown, the FT-IR pattern of H-MOR is as Figure 2 shown, and the FT-IR pattern of dealuminated MOR is asFigure 3 As shown, the FT-IR spectrum of Ti-MOR is as Figure 4 shown.

[0054] The catalytic activity of the synthesized Ti-MOR zeolite was evaluated by the cyclohexanone ammoximation reaction under the reaction conditions of: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were sequentially added to a flask, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 94.32%, and the selectivity of cyclohexanone oxime was 93.26%.

[0055] Example 2:

[0056] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for 2 h to obtain a gel precursor for synthesizing the zeolite. In terms of molar ratio, SiO2:Al2O3:KOH:additive:H2O in the gel precursor = 1:0.042:0.78:0.10:20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle and heated to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder, which was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps was placed in a quartz tube and pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0057] The catalytic activity of the synthesized Ti-MOR zeolite was evaluated by the cyclohexanone ammoximation reaction under the reaction conditions of: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were sequentially added to a flask, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 95.48%, and the selectivity of cyclohexanone oxime was 92.44%.

[0058] Example 3:

[0059] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for 2 hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2:Al2O3:KOH:additive:H2O in the gel precursor was 1:0.042:0.78:0.20:20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0060] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 91.99%, and the selectivity of cyclohexanone oxime was 91.51%.

[0061] Example 4:

[0062] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, additives and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additives : H2O in the gel precursor was 1 : 0.050 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to carry out a crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0063] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, catalyst and reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 50.47%, and the selectivity of cyclohexanone oxime was 85.84%.

[0064] Example 5:

[0065] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, additives and water are mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2:Al2O3:KOH:additives:H2O in the gel precursor is 1:0.083:0.78:0.05:20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they are loaded into a hydrothermal crystallization synthesis kettle together, and the temperature is raised to 180 °C to carry out a crystallization reaction for 96 h. After cooling, it is washed and dried to obtain MOR raw powder. It is subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it is calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps is treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it is calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps is placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample is washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0066] The catalytic activity of the synthesized Ti-MOR molecular sieve is evaluated by the cyclohexanone ammoximation reaction. The reaction conditions are as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process is as follows: tert-butanol, the catalyst and the reactants are added to the flask in sequence, and the reaction is carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction are as follows: the conversion rate of cyclohexanone is 52.04%, and the selectivity of cyclohexanone oxime is 82.73%.

[0067] Example 6:

[0068] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, additives and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2:Al2O3:KOH:additives:H2O = 1:0.042:0.53:0.05:20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to carry out a crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0069] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were as follows: the conversion rate of cyclohexanone was 85.37%, and the selectivity of cyclohexanone oxime was 94.38%.

[0070] Example 7

[0071] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, additives and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additives : H2O in the gel precursor was 1 : 0.042 : 0.62 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, MOR raw powder was obtained through washing and drying. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was further calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0072] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, catalyst and reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 79.86%, and the selectivity of cyclohexanone oxime was 94.33%.

[0073] Example 8:

[0074] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2:Al2O3:KOH:additive:H2O = 1:0.042:0.78:0.20:12. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to carry out a crystallization reaction for 96 h. After cooling, MOR raw powder was obtained through washing and drying. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0075] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence. Under stirring conditions, the reaction was carried out at 60 °C for 2 h. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 42.23%, and the selectivity of cyclohexanone oxime was 83.91%.

[0076] Example 9

[0077] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2 : Al2O3 : KOH : additive : H2O = 1 : 0.042 : 0.78 : 0.20 : 16. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to undergo a crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0078] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 48.80%, and the selectivity of cyclohexanone oxime was 90.47%.

[0079] Example 10:

[0080] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for 2 hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2 : Al2O3 : KOH : additive : H2O = 1 : 0.042 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1.5 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; if the silicon-aluminum ratio of the dealuminated sample was lower than 50, the operation of acid treatment for removing aluminum should be repeated until the silicon-aluminum ratio of the sample was greater than or equal to 50 (the same below). The sample obtained from the above steps was placed in a quartz tube and pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0081] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 49.73%, and the selectivity of cyclohexanone oxime was 87.48%.

[0082] Example 11:

[0083] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for 2 hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2 : Al2O3 : KOH : additive : H2O = 1 : 0.042 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C, and allowed to undergo a crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1.2 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was further calcined at 550 °C for 4 h to obtain dealuminated MOR; if the silicon-aluminum ratio of the dealuminated sample was lower than 50, the operation of acid treatment for aluminum removal should be repeated until the silicon-aluminum ratio of the sample was greater than or equal to 50 (the same below). The sample obtained in the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0084] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 54.26%, and the selectivity of cyclohexanone oxime was 86.62%.

[0085] Example 12:

[0086] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for 2 hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained from the above steps was treated with 6 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; if the silicon-aluminum ratio of the dealuminated sample was lower than 50, the operation of acid treatment for removing aluminum should be repeated until the silicon-aluminum ratio of the sample was greater than or equal to 50 (the same hereinafter). The sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0087] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence. Under stirring conditions, the reaction was carried out at 60 °C for 2 h. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 65.84%, and the selectivity of cyclohexanone oxime was 69.56%.

[0088] Example 13:

[0089] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for 2 hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2 : Al2O3 : KOH : additive : H2O = 1 : 0.042 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis autoclave together, and the temperature was raised to 180 °C to carry out a crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 10 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; if the silicon-aluminum ratio of the dealuminated sample was lower than 50, the operation of acid treatment for removing aluminum should be repeated until the silicon-aluminum ratio of the sample was greater than or equal to 50 (the same hereinafter). The sample obtained in the above steps was placed in a quartz tube and pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated at 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0090] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were sequentially added to a flask and reacted at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were as follows: the conversion rate of cyclohexanone was 90.84%, and the selectivity of cyclohexanone oxime was 92.56%.

[0091] Example 14:

[0092] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for 2 hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2 : Al2O3 : KOH : additive : H2O = 1 : 0.042 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C, and subjected to a crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; if the silicon-aluminum ratio of the dealuminated sample was lower than 50, the operation of acid treatment for removing aluminum should be repeated until the silicon-aluminum ratio of the sample was greater than or equal to 50 (the same below). The sample obtained in the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 45 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0093] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring. The reaction results measured after the reaction were as follows: the conversion rate of cyclohexanone was 94.45%, and the selectivity of cyclohexanone oxime was 94.25%.

[0094] Example 15:

[0095] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for 2 hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; if the silicon-aluminum ratio of the dealuminated sample was lower than 50, the operation of acid treatment for removing aluminum should be repeated until the silicon-aluminum ratio of the sample was greater than or equal to 50 (the same hereinafter). The sample obtained in the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 60 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and calcined at 550 °C for 4 h to obtain Ti-MOR.

[0096] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 93.31%, and the selectivity of cyclohexanone oxime was 94.25%.

[0097] Example 16:

[0098] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out a crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 400 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0099] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 76.81%, and the selectivity of cyclohexanone oxime was 83.33%.

[0100] Example 17:

[0101] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, additives and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additives : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, MOR raw powder was obtained through washing and drying. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 500 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0102] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, catalyst and reactants were sequentially added to a flask, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 86.91%, and the selectivity of cyclohexanone oxime was 91.86%.

[0103] Example 18:

[0104] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive and water are mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor is 1 : 0.042 : 0.78 : 0.05 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they are loaded into a hydrothermal crystallization synthesis kettle together, and the temperature is raised to 180 °C to carry out a crystallization reaction for 96 h. After cooling, it is washed and dried to obtain MOR raw powder. It is subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, and the solid-liquid ratio is 1:100. After washing again and drying at 80 °C, it is calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps is treated with 8 mol / L nitric acid at 80 °C for 20 h, and the solid-liquid ratio is 1:20. After washing and drying at 80 °C, it is calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps is placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 40 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample is washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0105] The catalytic activity of the synthesized Ti-MOR molecular sieve is evaluated by the cyclohexanone ammoximation reaction. The reaction conditions are as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process is as follows: tert-butanol, the catalyst and the reactants are added to the flask in sequence, and the reaction is carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction are as follows: the conversion rate of cyclohexanone is 93.85%, and the selectivity of cyclohexanone oxime is 92.46%.

[0106] Example 19:

[0107] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, additives and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additives : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.10 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, MOR raw powder was obtained through washing and drying. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated at 550 °C and 80 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0108] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, catalyst and reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 95.12%, and the selectivity of cyclohexanone oxime was 93.59%.

[0109] Example 20:

[0110] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 10 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0111] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 93.91%, and the selectivity of cyclohexanone oxime was 93.59%.

[0112] Example 21:

[0113] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to carry out a crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 15 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0114] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was: tert-butanol, catalyst, and reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 94.92%, and the selectivity of cyclohexanone oxime was 92.73%.

[0115] Example 22:

[0116] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2:Al2O3:KOH:additive:H2O = 1:0.042:0.78:0.20:20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out a crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 600 °C for 6 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0117] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 94.47%, and the selectivity of cyclohexanone oxime was 92.10%.

[0118] Example 23:

[0119] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2 : Al2O3 : KOH : additive : H2O = 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis autoclave together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 580 °C for 6 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0120] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 94.53%, and the selectivity of cyclohexanone oxime was 92.06%.

[0121] Example 24:

[0122] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, additives and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additives : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, MOR raw powder was obtained through washing and drying. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 8 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0123] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were as follows: the conversion rate of cyclohexanone was 94.85%, and the selectivity of cyclohexanone oxime was 94.84%.

[0124] Example 25:

[0125] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, MOR raw powder was obtained through washing and drying. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 10 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0126] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 94.61%, and the selectivity of cyclohexanone oxime was 91.68%.

[0127] Example 26:

[0128] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water are mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor is 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they are loaded into a hydrothermal crystallization synthesis kettle together, and the temperature is raised to 180 °C to carry out a crystallization reaction for 96 h. After cooling, it is washed and dried to obtain MOR raw powder. It is subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it is calcined at 550 °C for 8 h to obtain H-MOR. The sample obtained in the above steps is treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it is further calcined at 600 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps is placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample is washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0129] The catalytic activity of the synthesized Ti-MOR molecular sieve is evaluated by the cyclohexanone ammoximation reaction. The reaction conditions are as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process is as follows: tert-butanol, the catalyst, and the reactants are added to the flask in sequence, and the reaction is carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction are as follows: the conversion rate of cyclohexanone is 94.38%, and the selectivity of cyclohexanone oxime is 92.64%.

[0130] Example 27:

[0131] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive and water are mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2:Al2O3:KOH:additive:H2O in the gel precursor is 1:0.042:0.78:0.20:20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they are loaded into a hydrothermal crystallization synthesis kettle together, and the temperature is raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it is washed and dried to obtain MOR raw powder. It is subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, and the solid-liquid ratio is 1:100. After washing again and drying at 80 °C, it is calcined at 550 °C for 8 h to obtain H-MOR. The sample obtained in the above steps is treated with 8 mol / L nitric acid at 80 °C for 20 h, and the solid-liquid ratio is 1:20. After washing and drying at 80 °C, it is calcined at 580 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps is placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated at 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample is washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0132] The catalytic activity of the synthesized Ti-MOR molecular sieve is evaluated by the cyclohexanone ammoximation reaction. The reaction conditions are as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process is as follows: tert-butanol, the catalyst and the reactants are added to the flask in sequence, and the reaction is carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction are as follows: the conversion rate of cyclohexanone is 94.63%, and the selectivity of cyclohexanone oxime is 92.99%.

[0133] Example 28:

[0134] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2 : Al2O3 : KOH : additive : H2O = 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to carry out a crystallization reaction for 96 h. After cooling, MOR raw powder was obtained through washing and drying. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 8 h to obtain H-MOR. The sample obtained from the above steps was treated in 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0135] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were as follows: the conversion rate of cyclohexanone was 94.68%, and the selectivity of cyclohexanone oxime was 91.71%.

[0136] Example 29:

[0137] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 8 h to obtain H-MOR. The sample obtained in the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 8 h to obtain dealuminated MOR; the sample obtained in the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 4 h to obtain Ti-MOR.

[0138] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 94.85%, and the selectivity of cyclohexanone oxime was 94.39%.

[0139] Example 30:

[0140] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 8 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated at 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 600 °C for 4 h to obtain Ti-MOR.

[0141] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 94.64%, and the selectivity of cyclohexanone oxime was 92.91%.

[0142] Example 31:

[0143] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive and water are mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor is 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the mass of SiO2 in the gel precursor, they are loaded into a hydrothermal crystallization synthesis kettle together, and the temperature is raised to 180 °C to carry out a crystallization reaction for 96 h. After cooling, it is washed and dried to obtain MOR raw powder. It is subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, the solid-liquid ratio is 1:100, and after washing again and drying at 80 °C, it is calcined at 550 °C for 8 h to obtain H-MOR. The sample obtained in the above steps is treated with 8 mol / L nitric acid at 80 °C for 20 h, the solid-liquid ratio is 1:20, and after washing and drying at 80 °C, it is calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained in the above steps is placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample is washed and dried and then calcined at 580 °C for 4 h to obtain Ti-MOR.

[0144] The catalytic activity of the synthesized Ti-MOR molecular sieve is evaluated by the cyclohexanone ammoximation reaction. The reaction conditions are as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process is as follows: tert-butanol, the catalyst and the reactants are added to the flask in sequence, and the reaction is carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction are as follows: the conversion rate of cyclohexanone is 94.82%, and the selectivity of cyclohexanone oxime is 93.72%.

[0145] Example 32:

[0146] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, in the gel precursor, SiO2:Al2O3:KOH:additive:H2O = 1:0.042:0.78:0.20:20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to undergo a crystallization reaction for 96 h. After cooling, MOR raw powder was obtained through washing and drying. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 8 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 6 h to obtain Ti-MOR.

[0147] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence. Under stirring conditions, the reaction was carried out at 60 °C for 2 h. The reaction results measured after the reaction were as follows: the conversion rate of cyclohexanone was 94.33%, and the selectivity of cyclohexanone oxime was 93.00%.

[0148] Example 33:

[0149] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40%, an additive, and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : additive : H2O in the gel precursor was 1 : 0.042 : 0.78 : 0.20 : 20. After adding seeds with a mass ratio of 1:200 to the SiO2 in the gel precursor, they were loaded into a hydrothermal crystallization synthesis kettle together, and the temperature was raised to 180 °C to carry out the crystallization reaction for 96 h. After cooling, it was washed and dried to obtain MOR raw powder. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 8 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 8 h to obtain Ti-MOR.

[0150] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were as follows: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was as follows: tert-butanol, the catalyst, and the reactants were added to the flask in sequence, and the reaction was carried out at 60 °C for 2 h under stirring conditions. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 94.81%, and the selectivity of cyclohexanone oxime was 92.10%.

[0151] Comparative Example 1

[0152] Compared with Examples 1-3, in Comparative Example 1, additive DDS was not added during the synthesis process of MOR raw powder, that is, the molecular sieve catalyst was not modified, and the other preparation processes were basically the same. Specifically as follows:

[0153] At room temperature, aluminum sulfate octadecahydrate, potassium hydroxide, silica sol with a solid content of 40% and water were mixed and stirred for several hours to obtain a gel precursor for synthesizing molecular sieve. In terms of molar ratio, SiO2 : Al2O3 : KOH : H2O in the gel precursor was 1 : 0.021 : 0.78 : 20. After adding 0.05 g of seed crystals, they were loaded into a hydrothermal crystallization synthesis kettle together, heated to 180 °C to carry out the crystallization reaction for 96 h. After cooling, MOR raw powder was obtained through washing and drying. It was subjected to ammonium exchange treatment three times with 1 mol / L ammonium chloride solution at 80 °C, with a solid-liquid ratio of 1:100. After washing again and drying at 80 °C, it was calcined at 550 °C for 6 h to obtain H-MOR. The sample obtained from the above steps was treated with 8 mol / L nitric acid at 80 °C for 20 h, with a solid-liquid ratio of 1:20. After washing and drying at 80 °C, it was calcined at 550 °C for 4 h to obtain dealuminated MOR; the sample obtained from the above steps was placed in a quartz tube, pretreated at 500 °C for 2 h under a nitrogen purge of 30 ml / min, then contacted with TiCl4 heated to 60 °C at 550 °C for 6 h, and finally purged with nitrogen for 2 h. The obtained sample was washed and dried, and then calcined at 550 °C for 6 h to obtain Ti-MOR.

[0154] The XRD pattern of MOR raw powder is as Figure 5 shown, the XRD pattern of dealuminated MOR is as Figure 6 shown, the XRD pattern of Ti-MOR is as Figure 7 shown, the FT-IR pattern of H-MOR is as Figure 8 shown, the FT-IR pattern of dealuminated MOR is as Figure 9 shown, the FT-IR pattern of Ti-MOR is as Figure 10 shown.

[0155] The catalytic activity of the synthesized Ti-MOR molecular sieve was evaluated by the cyclohexanone ammoximation reaction. The reaction conditions were: 0.12 g of catalyst Ti-MOR, 0.39 g of cyclohexanone, 20 ml of tert-butanol, 0.45 g of hydrogen peroxide with a mass concentration of 30%, and 16.8 g of ammonia water. The specific process was: tert-butanol, catalyst and reactants were added to the flask in sequence, and reacted at 60 °C for 2 h under stirring. The reaction results measured after the reaction were: the conversion rate of cyclohexanone was 38.80%, and the selectivity of cyclohexanone oxime was 69.91%.

[0156] It can be seen from the attached drawings and the data of the comparative example and Examples 1-3 that compared with hydrogen-type MOR, the MOR raw powder after introducing DDS also has good crystallinity; the acid treatment and titanium supplementation processes did not destroy the crystallinity of the MOR sample; the MOR precursor prepared by introducing DDS has a peak in the range of 3100 - 3700 cm in the FT-IR spectrum -1There is a stronger peak there, indicating that it has more hydroxyl groups or hydroxyl nests (derived from the MOR raw powder with methyl groups after introducing DDS, and hydroxyl groups or hydroxyl nests are formed after calcination), and the acid treatment and titanium supplementation process do not destroy this part of the hydroxyl groups or hydroxyl nests.

[0157] It can be seen from the catalytic reaction test results of each example that, compared with the Ti-MOR molecular sieve in Comparative Example 1, the method of introducing DDS in Examples 1-3 makes the prepared Ti-MOR have better cyclohexanone ammoximation reaction activity.

[0158] As described above, these are only several embodiments of the present invention and do not impose any formal restrictions on the present invention. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A preparation method of MOR-type titanium silicalite molecular sieve for improving catalytic performance by introducing DDS, characterized in that, It includes the following steps: (1) Take a silicon source, an aluminum source, potassium hydroxide, water, and dimethyldimethoxysilane (DDS) as an additive, mix and stir evenly at room temperature to obtain a gel precursor for synthesizing a Ti-MOR zeolite precursor; Control the addition amounts of each raw material so that the molar ratio of SiO2:Al2O3:KOH:additive:H2O in the gel precursor is 1:0.042 - 0.083:0.53 - 0.78:0.05 - 0.20:12 - 20; the aluminum source is aluminum sulfate octadecahydrate; the silicon source is silica sol with a solid content of 40 wt%; (2) Load the gel precursor and an appropriate amount of MOR seeds into a hydrothermal crystallization synthesis kettle for crystallization reaction; after the reaction is completed, wash and dry the separated solid to obtain K + -type MOR precursor powder; the mass ratio of MOR seeds to SiO2 in the gel precursor is 1:200; the temperature of the crystallization reaction is 180 °C and the time is 96 h; (3) Mix the K + -type MOR precursor powder with an appropriate amount of ammonium chloride solution for ammonium exchange; repeat the ammonium exchange three times, and after washing, drying, and calcination, obtain the H + -type MOR; (4) Mix the H + -type MOR with nitric acid, and perform acid treatment to remove a part of aluminum in the framework; after washing to neutrality, perform drying and calcination treatments to obtain a dealuminated MOR precursor with defect sites; (5) Place the dealuminated MOR precursor in a quartz tube, first pretreat it with flowing hot nitrogen; then pass heated TiCl4 carried by flowing nitrogen through the dealuminated MOR precursor to achieve contact, and implant titanium atoms into the dealuminated MOR precursor through a gas-solid phase reaction; wash the titanium-supplemented MOR precursor powder to neutrality, and after drying and calcination, obtain the Ti-MOR zeolite.

2. The method according to claim 1, characterized in that In the step (1), the stirring time during mixing at room temperature is 2 hours.

3. The method according to claim 1, wherein In the step (3), the concentration of the ammonium chloride solution is 1 - 1.5 mol / L, the solid-liquid ratio of the MOR precursor powder to the ammonium chloride solution is 1:100, the ammonium exchange temperature is 80 °C, and when the sodium oxide content in 0.01 g of the zeolite is detected to be ≤ 1000 ppm, it is regarded as the completion of ammonium exchange; the drying temperature after ammonium exchange is 80 °C until it is dried; the calcination temperature is 550 - 600 °C, and the time is 6 - 10 h.

4. The method according to claim 1, characterized in that, In the step (4), the nitric acid concentration is 6 - 10 mol / L, the solid-liquid ratio of MOR to nitric acid is 1:20, the acid treatment time is 20 hours, and the temperature is 80 °C; the drying temperature is 80 °C until it is dried; the calcination temperature is 550 - 600 °C, and the time is 4 - 8 h.

5. The method according to claim 1, wherein In the step (4), when the silicon-aluminum ratio of the dealuminated sample is lower than 50, repeat the operation of acid treatment for dealumination until the silicon-aluminum ratio of the sample is greater than or equal to 50.

6. The method according to claim 1, wherein In the step (5), place TiCl4 in a bubbling bottle and heat it to make nitrogen pass through the bubbling bottle and carry TiCl4 into the quartz tube; control the flow rate of nitrogen to be 30 - 60 mL / min, and the heating temperature of TiCl4 in the bubbling bottle is 40 °C - 80 °C.

7. The method according to claim 1, characterized in that In the step (5), control the temperature of the gas-solid phase reaction in the quartz tube to be 400 - 550 °C, and the time is 6 - 15 h; the calcination temperature is 550 °C - 600 °C, and the time is 4 - 8 h.

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