Modification method of Ti-MOR titanium silicalite molecular sieve and application of Ti-MOR titanium silicalite molecular sieve in ammoximation reaction

Abstract

The invention discloses a modification method of a Ti-MOR titanium silicalite molecular sieve and an application of the Ti-MOR titanium silicalite molecular sieve in ammoximation reaction, and is characterized in that the Ti-MOR topological structure titanium silicalite molecular sieve Ti-MOR is used as a raw material, silicon is inserted into a skeleton defect site through high-temperature gas-solid phase reaction with silicon tetrachloride steam, and the Ti-MOR titanium silicalite molecular sieve with a constant skeleton crystal structure is prepared. The modified Ti-MOR titanium silicalite molecular sieve catalyst with repaired skeleton defects is obtained, the Ti-MOR titanium silicalite molecular sieve chemically treated by silicon tetrachloride is used as the catalyst for one-step ammoximation reaction of a carbonyl-containing reaction substrate, ammonia and hydrogen peroxide to prepare oxygen / nitrogen-containing oxime chemicals, and both the ketone conversion rate and the ketoxime selectivity of the product are up to 99%. Compared with the prior art, the method provided by the invention has the advantages of good catalytic performance, environmental friendliness and simple and convenient post-treatment, further broadens the research and application field of ammoximation catalytic reaction, and has very important industrial application value and good application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of inorganic catalysts and their applications, in particular to a modification method of a Ti-MOR titanium silicon molecular sieve and its application in an ammoximation reaction. Background Art

[0002] Zeolite molecular sieves are a type of microporous material with unique crystal structure, sub-nanometer multidimensional pores at molecular scale, and adjustable skeleton elements. They are widely used in ion exchange, adsorption separation, catalysis and other fields. Among them, silica-alumina zeolite is used on a large scale as a solid acid catalyst in industrial processes such as petroleum refining, energy chemical industry and shape-selective catalysis; and the titanium silicalite molecular sieve obtained by isomorphous substitution of titanium on its silicon oxide skeleton has the characteristics of mild reaction conditions, high selectivity for target oxygen-containing (nitrogen) chemicals, and water as the only by-product when catalyzing the liquid-phase oxidation reaction of hydrocarbons and hydrogen peroxide. It has been widely used and promoted in the green synthesis process of propylene oxide, hydroquinone and ketoxime products, and has achieved milestone results recognized at home and abroad in the field of catalysis. The first generation of titanium silicalite molecular sieve is the TS-1 catalyst with MFI topology. Due to its relatively small 10-membered ring pores, the improvement of catalytic performance and application promotion have encountered bottlenecks. To this end, large microporous titanium silicalite molecular sieves containing 12-membered ring channels have been developed, such as MOR topology Ti-MOR, MWW topology Ti-MWW and *BEA topology Ti-Beta. Ti-MOR shows better catalytic performance than TS-1 in the one-step ammoximation reaction of ketones or aldehydes with hydrogen peroxide and ammonia to synthesize oxime chemicals, and has been put into practical industrial application.

[0003] The new generation of Ti-MOR titanium silicalite shows better ammoximation performance than the traditional TS-1 titanium silicalite, which is due to the chemical modification of Ti-MOR titanium silicalite, such as alkaline silicon dissolution to form mesopores (J. Catal., 2011, 281, 263), fluoride treatment (J. Catal., 2014, 320, 160), alkali metal cation exchange (J. Catal., 2014, 309, 1) and other chemical modifications, which effectively improve the performance of Ti-MOR catalytic ammoximation reaction from the perspective of enhancing the diffusion and mass transfer performance of Ti-MOR, improving the chemical microenvironment of the titanium active center of Ti-MOR, and eliminating the acidity that is unfavorable to the reaction. Further exploring the potential catalytic performance of Ti-MOR is inseparable from the development of more suitable new chemical modification methods. Inhibiting the hydrophilicity of Ti-MOR titanium silicalite and appropriately increasing and improving its hydrophobicity is expected to further improve the catalytic performance of Ti-MOR catalysts in water-related reaction systems. Silanization of silicon oxide materials in organic solvents using expensive organosilicon reagents is a well-known conventional method for improving the hydrophobicity of zeolite molecular sieves and mesoporous silicon oxide materials (Chem. Commun., 1996, 145). However, the use of organic raw materials leads to high processing costs and environmental pollution.

[0004] Adhering to the concept of "green chemistry", we develop methods to rationally utilize inorganic modified Ti-MOR titanium silicalite to reduce environmental load, improve industrial feasibility and practical application value, and hope to create more efficient selective oxidation catalytic materials and form new catalytic reaction technology. Summary of the invention

[0005] The purpose of the present invention is to provide a modification method of Ti-MOR titanium silicon molecular sieve and its application in ammoximation reaction in view of the deficiencies of the prior art. MOR topological structure titanium silicon molecular sieve Ti-MOR is used as raw material, and high-temperature gas-solid phase reaction with silicon tetrachloride steam is performed to make silicon insert into the skeleton defect position due to the reaction of silicon tetrachloride gas phase treatment with hydrophilic hydroxyl groups, so as to obtain a modified Ti-MOR titanium silicon molecular sieve catalyst with the skeleton crystal structure maintained unchanged and the skeleton defect position repaired, so that the titanium coordination state and affinity are significantly optimized and adjusted, and the hydrophobicity of Ti-MOR titanium silicon molecular sieve is greatly improved. The modification method has the advantages of good catalytic performance, environmental friendliness, and simple post-processing, and the process flow is simple, easy to operate, and has strong feasibility of amplification. The Ti-MOR catalyst after chemical modification of silicon tetrachloride is mixed and stirred with ketones, ammonia and hydrogen peroxide, and a one-step liquid phase ammoximation reaction can be realized to efficiently prepare the corresponding ketoxime product, and the ketone conversion rate and product ketoxime selectivity are both as high as 99%. It further broadens the research and application fields of ammonia oximation catalytic reactions and has very important industrial application value and good application prospects.

[0006] The object of the present invention is achieved by: a modification method of Ti-MOR titanium silicon molecular sieve, which is characterized in that a commercially available MOR topological structure titanium silicon molecular sieve Ti-MOR is used as a raw material, and a modified Ti-MOR titanium silicon molecular sieve catalyst is prepared by high-temperature gas-solid phase reaction with silicon tetrachloride vapor, wherein the framework crystal structure is maintained unchanged, the framework defect sites are repaired, and the titanium coordination state and affinity are optimized and adjusted. The preparation specifically comprises the following steps:

[0007] Step 1: Load the commercially available MOR topology titanium silicon molecular sieve Ti-MOR powder solid into a fixed bed tubular reactor, heat the reaction tube to 300-500°C, and under this temperature condition, purge with dry nitrogen for 2-5 hours to dehydrate the loaded Ti-MOR titanium silicon molecular sieve solid.

[0008] Step 2: The temperature of the reaction tube filled with Ti-MOR titanium silicon molecular sieve is adjusted to 100 ~ 600 ° C, and dry nitrogen is used as a carrier to flow through the silicon tetrachloride liquid storage tank, and the silicon tetrachloride vapor is brought into the reaction tube to contact with the dehydrated Ti-MOR titanium silicon molecular sieve solid for chemical reaction. The weight ratio of the amount of silicon tetrachloride brought into the reaction tube by the nitrogen carrier gas per unit time to the Ti-MOR titanium silicon molecular sieve is 0.01 ~ 2 h -1 The treatment time is 0.1 to 4 hours. After the treatment, switch to pure nitrogen carrier gas and purge for 1 hour at the same temperature to remove the silicon tetrachloride physically adsorbed on the Ti-MOR solid surface.

[0009] Step 3: Cool the reaction tube to room temperature in a nitrogen atmosphere, cool the tetrachlorosilane-treated reaction tube to room temperature, take out the tetrachlorosilane-treated Ti-MOR titanium silicon molecular sieve solid filled therein, repeatedly wash and filter with deionized water until the filtrate pH is > 6, and dry in an oven at 100 to 120°C for 2 to 5 hours to finally obtain the Ti-MOR titanium silicon molecular sieve catalytic material chemically treated with silicon tetrachloride.

[0010] The invention discloses an application of a catalyst prepared by a modification method of Ti-MOR titanium silicon molecular sieve in an ammoximation reaction, wherein the catalyst is used for a one-step ammoximation reaction of a carbonyl reaction substrate, ammonia and hydrogen peroxide to prepare an oxygen / nitrogen-containing oxime chemical. The specific operation is as follows:

[0011] Step 1: sequentially add the Ti-MOR titanium silicon molecular sieve catalyst chemically treated with silicon tetrachloride, the organic reaction substrate containing carbonyl, the oxidant and the ammonia source reactant to a glass flask reactor, heat to 50-80° C. in a constant temperature water bath, and stir to react for 0.5-2 hours, wherein the molar ratio of the organic reaction substrate containing carbonyl to the oxidant is 0.5-1.2; the molar ratio of the ammonia source to the organic reaction substrate containing carbonyl is 1.0-2.0; the mass ratio of the Ti-MOR titanium silicon molecular sieve catalyst chemically treated with silicon tetrachloride to the organic reaction substrate containing carbonyl is 0.2-1; the organic reaction substrate is a carbonyl-containing ketone compound, and the carbon number thereof ranges from 3 to 6; the oxidant is a hydrogen peroxide aqueous solution, and the mass concentration thereof ranges from 5 to 50%; the ammonia source is one or a mixture of two or more selected from ammonia gas, ammonia water, ammonium bicarbonate and ammonium carbonate.

[0012] Step 2: After the reaction is completed, the glass flask is placed in an ice-water bath for cooling, and the catalyst solid is removed by centrifugation to obtain the corresponding ketoxime product. The reaction liquid is analyzed by gas chromatography to determine the conversion rate of the organic reaction substrate and the selectivity of the ketoxime product.

[0013] Compared with the prior art, the present invention has the following beneficial technical effects and significant technical progress:

[0014] 1) The chemical modification of silicon tetrachloride of the present invention focuses on precisely controlling its hydrophilicity and hydrophobicity without the need to use expensive organosilane reagents;

[0015] 2) The raw materials required for the present invention are widely available, the preparation process is simple, no organic solvent is required, the process is environmentally friendly, and it is easy to industrialize;

[0016] 3) The present invention can greatly improve the catalytic performance of Ti-MOR catalyst in clean synthesis of ketoxime chemicals, with the ketone conversion rate and product ketoxime selectivity both reaching 99%, further broadening the research and application fields of ammonia oximation catalytic reactions, forming a greener and more environmentally friendly catalytic process technology, and having very important industrial application value and good application prospects;

[0017] 4) The present invention has the advantages of good catalytic performance, environmental friendliness, and simple post-treatment, and the process flow is simple, the operation is simple, and the feasibility of scale-up is strong. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of a Ti-MOR titanium silicon molecular sieve silicon tetrachloride steam gas solid phase treatment device;

[0019] Figure 2 The X-ray diffraction spectra of Ti-MOR titanium silicon molecular sieve before and after chemical modification of silicon tetrachloride;

[0020] Figure 3 Scanning electron microscope photos of Ti-MOR titanium silicon molecular sieve before and after chemical modification of silicon tetrachloride;

[0021] Figure 4 Weight loss (TG) determination curve of Ti-MOR titanium silicon molecular sieve before and after chemical modification of silicon tetrachloride; DETAILED DESCRIPTION

[0022] The raw materials, chemical treatment method and catalytic application of the present invention are further described in detail below through specific examples. In order to simplify the description, only key steps and technical parameters are listed.

[0023] Example 1

[0024] See also Figure 1 The preparation of the modified Ti-MOR titanium silicon molecular sieve catalyst specifically includes the following steps:

[0025] Step 1: Dehydration

[0026] 5 g of MOR topological structure titanium silicon molecular sieve Ti-MOR powder was loaded into a fixed bed tubular reactor, the reaction tube was heated to 500° C., and dry nitrogen was used for purging for 2.5 hours to dehydrate the loaded Ti-MOR titanium silicon molecular sieve solid.

[0027] Step 2: Modification

[0028] The temperature of the reaction tube after dehydration in step 1 was adjusted to 400°C, and nitrogen was passed through the liquid storage tank of silicon tetrachloride to bring silicon tetrachloride vapor into the reaction tube. The Ti-MOR titanium silicon molecular sieve was subjected to gas-solid phase treatment for 1 hour, during which the mass of silicon tetrachloride vapor brought into the reaction tube was 0.5g. Then, the gas line was switched to dry pure nitrogen, which was purged at 500°C for half an hour to remove the silicon tetrachloride physically adsorbed on the Ti-MOR solid surface.

[0029] Step 3: Wash and Dry

[0030] In a nitrogen atmosphere, the tetrachlorosilane-treated reaction tube was cooled to room temperature, the Ti-MOR titanium silicon molecular sieve solid treated with tetrachlorosilane filled therein was taken out, and the solid was repeatedly washed and filtered with deionized water until the pH of the filtrate was > 6, and dried in an oven at 115° C. for 3 hours to obtain the Ti-MOR titanium silicon molecular sieve catalytic material chemically modified with tetrachlorosilane.

[0031] See also Figure 2The Ti-MOR catalyst chemically modified with silicon tetrachloride prepared above was characterized by X-ray diffraction (Cu-Kα,λ = 1.5406 Å). The crystalline structure was a MOR topological structure, and its crystallinity was equivalent to that of the Ti-MOR parent material before silicon tetrachloride modification. The silicon tetrachloride treatment did not cause the collapse of the crystal structure.

[0032] See also Figure 3 a, The Ti-MOR matrix material before SiCl4 modification showed a blocky nanocrystal morphology with a size of 200 ~ 500 nm under scanning electron microscopy.

[0033] See also Figure 3 b. The crystal morphology and size of the Ti-MOR catalyst chemically modified with silicon tetrachloride prepared in Example 1 as shown by scanning electron microscopy are similar to those of the Ti-MOR parent material before modification with silicon tetrachloride.

[0034] See also Figure 4 The Ti-MOR catalyst chemically modified with silicon tetrachloride prepared in Example 1, after saturated water absorption, was tested by thermogravimetric test, and its water adsorption capacity was 4.86%, which was significantly decreased compared with the water adsorption capacity (9.96%) of the Ti-MOR parent material before silicon tetrachloride modification. The chemical modification with silicon tetrachloride significantly reduced the hydrophilicity of the Ti-MOR catalyst, that is, effectively improved its hydrophobicity.

[0035] Example 2

[0036] Step 1: 3 g of MOR topology structure titanium silicon molecular sieve Ti-MOR powder is loaded into a fixed bed tubular reactor, the reaction tube is heated to 400° C., and dry nitrogen is used for purging for 3.5 hours to dehydrate the loaded Ti-MOR titanium silicon molecular sieve solid.

[0037] Step 2: Adjust the temperature of the reaction tube after dehydration in step 1 to 500°C, pass nitrogen through the liquid storage tank of silicon tetrachloride, bring silicon tetrachloride vapor into the reaction tube, and perform gas-solid phase treatment on Ti-MOR titanium silicon molecular sieve for 2 hours, during which the mass of silicon tetrachloride vapor brought into the reaction tube is 1.0g. Then, switch the gas line to dry pure nitrogen, purge at 500°C for half an hour to remove silicon tetrachloride physically adsorbed on the solid surface of Ti-MOR.

[0038] Step 3: In a nitrogen atmosphere, the tetrachlorosilane-treated reaction tube was cooled to room temperature, the Ti-MOR titanium silicon molecular sieve solid treated with tetrachlorosilane filled therein was taken out, and the solid was repeatedly washed and filtered with deionized water until the pH of the filtrate was > 6, and dried in an oven at 110° C. for 4 hours to finally obtain the Ti-MOR titanium silicon molecular sieve catalytic material chemically treated with tetrachlorosilane.

[0039] The Ti-MOR catalyst chemically modified with silicon tetrachloride prepared in Example 2 was characterized by X-ray diffraction (Cu-Kα, λ =1.5406 Å), and the crystalline structure was a MOR topological structure, and its crystallinity was equivalent to that of the Ti-MOR parent material before silicon tetrachloride modification. The silicon tetrachloride treatment did not cause the collapse of the crystal structure.

[0040] The Ti-MOR catalyst chemically modified with silicon tetrachloride prepared in Example 2, after saturated water absorption, has a water adsorption capacity of 4.3% as measured by thermogravimetric test (TG), which is significantly decreased compared with the water adsorption capacity (9.96%) of the Ti-MOR parent material before silicon tetrachloride modification. The chemical modification with silicon tetrachloride significantly reduces the hydrophilicity of the Ti-MOR catalyst, that is, effectively improves the hydrophobicity.

[0041] The Ti-MOR titanium silicon molecular sieve chemically modified with silicon tetrachloride prepared in Example 1 was used as a catalyst in the following reaction of ammoximation of ketone, ammonia and hydrogen peroxide to prepare the corresponding ketoxime (Examples 3 to 5), and it was found that it exhibited a better catalytic activity than the unmodified Ti-MOR original.

[0042] Example 3

[0043] Step 1: 0.5 g of the Ti-MOR titanium silicon molecular sieve chemically modified with silicon tetrachloride prepared in Example 1, 20 mmol of cyclohexanone, 22 mmol of hydrogen peroxide (6% aqueous solution by mass concentration), and 25 mmol of ammonia water (25% aqueous solution by mass concentration) were added to a glass flask reactor in sequence, heated to 70° C. in a constant temperature water bath, and stirred for reaction for 2 hours.

[0044] Step 2: After the reaction is completed, the glass flask is placed in an ice-water bath for cooling, the catalyst solid is removed by centrifugation, and the liquid product is analyzed by gas chromatography (Shimadzu 2014, FID detector) to calculate the cyclohexanone conversion rate and the selectivity of the target product cyclohexanone oxime.

[0045] The comparison of the results of the cyclohexanone ammoximation reaction using the Ti-MOR catalyst without chemical modification of silicon tetrachloride in Example 3 and Comparative Example 1 is shown in Table 1 below:

[0046] Table 1 Comparison of the cyclohexanone ammoximation reaction performance of Example 3 and Comparative Example 1

[0047] Cyclohexanone conversion rate (%) Cyclohexanone oxime selectivity (%) Example 3 99.6 99.8 Comparative Example 1 75.3 98.6

[0048] The Ti-MOR catalyst not chemically modified with silicon tetrachloride used in Comparative Example 1 is the same as the Ti-MOR raw material used in Example 1, and the conditions for the ammoximation reaction of cyclohexanone, ammonia and hydrogen peroxide are the same as those in Example 3. The product was analyzed by gas chromatography, and the measured data proved that the Ti-MOR catalyst chemically modified with silicon tetrachloride used in Example 3 had a more superior catalytic performance than the Ti-MOR catalyst not chemically modified with silicon tetrachloride.

[0049] Example 4

[0050] Step 1: 0.45 g of the Ti-MOR titanium silicon molecular sieve chemically modified with silicon tetrachloride prepared in Example 1, 18 mmol of butanone, 25 mmol of hydrogen peroxide (aqueous solution with a mass concentration of 10%), and 28 mmol of ammonia water (aqueous solution with a mass concentration of 25%) were added to a glass flask reactor in sequence, heated to 65° C. in a constant temperature water bath, and stirred for reaction for 1.5 hours.

[0051] Step 2: After the reaction is completed, the glass flask is placed in an ice-water bath for cooling, the catalyst solid is removed by centrifugation, and the liquid product is analyzed by gas chromatography (Shimadzu 2014, FID detector), and the butanone conversion rate and the selectivity of the target product of butanone oxime (methyl ethyl ketone oxime) are calculated. The results of the butanone ammoximation reaction using the original Ti-MOR catalyst without silicon tetrachloride chemical modification in Example 4 and Comparative Example 2 are compared in detail in Table 2 below:

[0052] Table 2 Comparison of butanone ammoximation reaction performance between Example 4 and Comparative Example 2

[0053] Butanone conversion rate (%) Butanone oxime selectivity (%) Example 4 99.8 99.3 Comparative Example 2 75.6 97.3

[0054] The Ti-MOR catalyst not chemically modified with silicon tetrachloride used in Comparative Example 2 is the same as the Ti-MOR raw material used in Example 2, and the conditions for the ammoximation reaction of butanone, ammonia and hydrogen peroxide are the same as those in Example 4. The product was analyzed by gas chromatography, and the measured data proved that the Ti-MOR catalyst chemically modified with silicon tetrachloride used in Example 4 has a more superior catalytic performance than the Ti-MOR catalyst not chemically modified with silicon tetrachloride.

[0055] Example 5

[0056] Step 1: 0.35 g of the Ti-MOR titanium silicon molecular sieve chemically modified with silicon tetrachloride prepared in Example 1, 15 mmol acetone, 16.5 mmol hydrogen peroxide (30% aqueous solution by mass concentration), and 18 mmol ammonia water (25% aqueous solution by mass concentration) were added to a glass flask reactor in sequence, heated to 60° C. in a constant temperature water bath, and stirred for reaction for 3 hours.

[0057] Step 2: After the reaction is completed, the glass flask is placed in an ice-water bath for cooling, the catalyst solid is removed by centrifugation, and the liquid product is analyzed by gas chromatography (Shimadzu 2014, FID detector), and the acetone conversion rate and the selectivity of the target product of propionoxime are calculated. The results of the acetone ammoximation reaction using the original Ti-MOR catalyst without silicon tetrachloride chemical modification in Example 5 and Comparative Example 3 are compared in detail in Table 3 below:

[0058] Table 3 Comparison of acetone ammoximation reaction performance between Example 5 and Comparative Example 3

[0059] Acetone conversion rate (%) Acetone oxime selectivity (%) Example 5 99.2 99.4 Comparative Example 3 77.8 96.8

[0060] The Ti-MOR catalyst not chemically modified with silicon tetrachloride used in Comparative Example 3 is the same as the Ti-MOR raw material used in Example 5, and the conditions used for the ammoximation reaction of acetone, ammonia and hydrogen peroxide are the same as those in Example 5. The product was analyzed by gas chromatography, and the measured data proved that the Ti-MOR catalyst chemically modified with silicon tetrachloride used in Example 4 had a more superior catalytic performance than the Ti-MOR catalyst not chemically modified with silicon tetrachloride.

[0061] The protection content of the present invention is not limited to the above embodiments. Without departing from the spirit and scope of the inventive concept, any simple modification or modification in form made by those skilled in the art to the embodiments of the present invention is included in the present invention and is protected by the attached claims. Other fine adjustments to the raw materials, feed ratio, temperature, time and other conditions of the present invention are considered to infringe the rights and interests of the present invention.

Claims

1. A method for modifying Ti-MOR titanium silicon molecular sieve, characterized in that: The modified Ti-MOR titanium silicon molecular sieve catalyst is prepared by using a MOR topological structure titanium silicon molecular sieve Ti-MOR and silicon tetrachloride to react in a gas-solid phase to insert silicon into the framework defect position, thereby obtaining a modified Ti-MOR titanium silicon molecular sieve catalyst having an unchanged framework crystal structure and repaired framework defect positions. The preparation specifically includes the following steps: Step 1: using dry nitrogen to purge the MOR topological titanium silicon molecular sieve Ti-MOR powder solid filled in the reaction tube at a temperature of 300 to 500 ° C for 2 to 5 hours for dehydration treatment; Step 2: Using dry nitrogen as a carrier, silicon tetrachloride vapor is brought into the reaction tube to modify the dehydrated Ti-MOR titanium silicon molecular sieve solid for 0.1 to 4 hours. The weight ratio of silicon tetrachloride brought into the reaction tube by nitrogen carrier gas per unit time to Ti-MOR titanium silicon molecular sieve is 0.01 to 2 h-1. After the treatment is completed, switch to pure nitrogen and purge at the same temperature for 1 hour to remove silicon tetrachloride physically adsorbed on the surface of Ti-MOR solid; Step 3: The reaction tube is cooled to room temperature in a nitrogen atmosphere, the Ti-MOR titanium silicon molecular sieve solid treated with tetrachlorosilane is taken out, and the solid is repeatedly washed and filtered with deionized water until the pH value of the filtrate is > 6, and dried at a temperature of 100 to 120°C for 2 to 5 hours to obtain a Ti-MOR titanium silicon molecular sieve catalytic material chemically modified with silicon tetrachloride.

2. Use of a catalyst prepared by the modification method of the Ti-MOR titanium silicon molecular sieve according to claim 1 in an ammoximation reaction, characterized in that: The Ti-MOR titanium silicon molecular sieve chemically treated with silicon tetrachloride is used as a catalyst for a one-step ammoximation reaction of a carbonyl reaction substrate, ammonia and hydrogen peroxide to prepare oxygen / nitrogen-containing oxime chemicals. The specific operation is as follows: Step 1: sequentially add a Ti-MOR titanium silicon molecular sieve catalyst chemically treated with silicon tetrachloride, an organic reaction substrate containing carbonyl groups, an oxidant and an ammonia source reactant into a reactor, and stir the reaction at a temperature of 50 to 80°C for 0.5 to 2 hours; the organic reaction substrate is a carbonyl-containing ketone compound having a carbon number of 3 to 6; the oxidant is a hydrogen peroxide aqueous solution having a mass concentration of 5 to 50%; the ammonia is one or a mixture of two or more selected from ammonia gas, ammonia water, ammonium bicarbonate and ammonium carbonate; the molar ratio of the organic reaction substrate containing carbonyl groups to the oxidant is 0.5 to 1.2; the molar ratio of ammonia to the organic reaction substrate containing carbonyl groups is 1.0 to 2.0; the mass ratio of the Ti-MOR titanium silicon molecular sieve chemically treated with silicon tetrachloride to the organic reaction substrate containing carbonyl groups is 0.2 to 1; Step 2: After the reaction is completed, the reaction solution is cooled and centrifuged to remove the catalyst solid, and the product is the corresponding ketoxime product. The reaction solution is analyzed by gas chromatography to determine the conversion rate of the organic reaction substrate and the selectivity of the ketoxime product.

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