Multi-metal supported catalyst with mimic enzyme function as well as preparation method and application of multi-metal supported catalyst

Abstract

The invention provides a multi-metal supported catalyst with a mimic enzyme function as well as a preparation method and application of the multi-metal supported catalyst. The multi-metal supported catalyst comprises a carrier, two transition metals and an alkali metal. The functional bionic principle is used for catalyst design, the distribution of active sites is regulated and controlled according to the chemical thermodynamics principle, and the atomic size required by multi-site coordination is achieved. According to the preparation method of the catalyst, the problem that no synergistic isolated site is generated is solved, the Na-Ir-W-ITQ-1 and K-Co-ZSM-57 catalysts have excellent catalytic performance when applied to propylene air epoxidation, and the selectivity of propylene oxide is larger than or equal to 85% when the conversion per pass reaches 15% or above.

Description

Technical Field

[0001] The present application relates to the field of petrochemical technology, and in particular to an enzyme-mimicking functional multi-metal supported catalyst and its preparation method and application. Background Art

[0002] Propylene oxide (PO) is the third-largest derivative of propylene and an important basic organic chemical raw material. Its downstream derivatives include nearly 100 products, including polyethers, polyols, propylene glycol, surfactants, and oilfield demulsifiers. It is widely used in industries such as polyurethane plastics, construction, food, pharmaceuticals, and cosmetics. The industrial synthesis of PO uses propylene as a raw material and primarily involves three methods: the chlorohydrin method, the hydrogen peroxide method, and the co-oxidation method. These industrial methods each have their own drawbacks and shortcomings. For example, the chlorohydrin method produces a large amount of calcium salt as a byproduct, hydrogen peroxide has high raw material costs, and the co-oxidation method is limited by market demand for the co-oxidation product.

[0003] Currently, the direct epoxidation of propylene with molecular oxygen faces significant challenges due to the lack of highly selective catalytic materials that can both highly activate molecular oxygen and suppress side reactions such as allylic hydrogen oxidation. This application designs a synergistically designed catalyst based on the spatial dimensions of an alkali metal and two transition metal supports. The two transition metals have a thermodynamic tendency to form salts, making the synergy between the three metal ions feasible and regular at the atomic scale. These catalytic materials demonstrate high catalytic activity, high selectivity, and good stability in the epoxidation of propylene and other olefins. Summary of the Invention

[0004] The present application aims to solve the shortcomings of the prior art and to provide several multi-metal-loaded enzyme-mimicking catalysts with high selectivity and high activity for olefin epoxidation reactions.

[0005] Based on the strong effect of complex ion pairs, this application regulates the catalyst-loaded multi-metal center to a spatially coordinated site with atomic size; secondly, the prepared multi-metal-loaded catalyst is applied to the epoxidation reaction of propylene, 3-chloropropylene, cyclohexene, and styrene.

[0006] The technical solution adopted in the present application is: an enzyme-mimicking functional multi-metal supported catalyst, wherein the multi-metal supported catalyst comprises a carrier, two transition metals, and an alkali metal.

[0007] Furthermore, the carrier is one of nano-silica, ZSM-57, and ITQ-1 molecular sieve.

[0008] Furthermore, of the two transition metals, one added in the form of a cationic solution is: manganese (Mn 2+ ), cobalt (Co 2+ ) Nickel (Ni 2+), copper (Cu 2+ ), iridium (Ir 3+ ) one of them; the other one is added as a metal anion solution: molybdenum (MoO4 2- ), tungsten (WO4 2- ), bismuth (BiO 3- ) is one of the following.

[0009] Furthermore, the alkali metal is one of lithium, sodium and potassium.

[0010] The preparation method of a multi-metal supported catalyst with enzyme-mimicking function includes the following steps: dispersing a carrier in deionized water, adding a transition metal anion solution to the suspension under vigorous stirring, stirring for several minutes, adding another transition metal cation solution, stirring for several minutes, filtering, washing with deionized water, and drying at 80°C for 3 hours; suspending the obtained solid in deionized water, adding an alkali metal ion salt solution, stirring for several minutes, adding ammonia water to adjust the pH to 7-11, filtering, washing with deionized water, drying at 60-120°C, and then calcining in a muffle furnace at 300-600°C to prepare the supported catalyst.

[0011] Furthermore, the metal loading in the supported catalyst is: anionic transition metal loading is 0.1-5 wt %, cationic transition metal loading is 0-5 wt %, and alkali metal loading is 0.1-3 wt %.

[0012] Application of enzyme-mimicking functional multi-metal supported catalyst, wherein the catalyst is applied to olefin epoxidation reaction.

[0013] Furthermore, the olefin is one of propylene, allyl chloride, cyclohexene, and styrene, and the oxidant for the epoxidation reaction is oxygen.

[0014] Furthermore, the olefin is propylene, and the reaction process is to load the catalyst into a fixed bed reactor, and pass propylene, oxygen, and balance gas into the fixed bed for a heterogeneous reaction, wherein the balance gas is nitrogen or argon; the fixed bed reaction conditions are a temperature of 80~350°C, a pressure of 0.1~3 MPa, and a volume ratio of each gas feed: propylene: balance gas: oxygen = 1:0~20:0.1~0.5.

[0015] Furthermore, the olefins are allyl chloride, cyclohexene, and styrene, and the reaction process is to add a solvent, an olefin raw material, and a catalyst into a stainless steel autoclave, fill the stainless steel autoclave with oxygen and a balance gas, and react under certain conditions; the solvent is one of acetonitrile, tetrahydrofuran, dioxane, cyclohexane, n-heptane, N,N-dimethylformamide (DMF), and N-methylpyrrolidone (NMP), and the balance gas is nitrogen or argon; the enzyme-mimicking multi-metal supported catalyst is used in the epoxidation reaction of allyl chloride, cyclohexene, and styrene, and the reaction conditions are: temperature 80~350℃, pressure 0.1~5MPa.

[0016] The present application achieves the following beneficial effects: Disclosed herein are methods for preparing multi-metal supported catalysts with enzyme-mimetic functions and their application in olefin epoxidation reactions. These methods primarily address the difficulty in achieving both conversion and selectivity when using air (or oxygen) as the oxidant for olefin epoxidation. This application utilizes the principles of functional biomimetic catalyst design, regulating the distribution of active sites based on chemical thermodynamics to achieve the atomic size required for multi-site synergy. First, a metal anion solution (tungstate, molybdate, bismuthate) is added to a suspension of a support (nanosilica, ZSM-57, ITQ-1) or its precursor sol, followed by a transition metal cation solution (manganese, cobalt, nickel, copper, iridium), allowing the two metals to be uniformly deposited in a salt-forming manner. The resulting supported material is then treated with an alkali metal ion solution (lithium, sodium, or potassium), filtered, dried, and calcined to yield a series of multi-metal supported catalysts.

[0017] The catalyst of the present application overcomes the problem of no synergistic isolated sites in the preparation method, and has the beneficial effect that the Na-Ir-W-ITQ-1 and K-Co-ZSM-57 catalysts have excellent catalytic performance when applied to the air epoxidation of propylene, and the propylene oxide selectivity is ≥85% when the single-pass conversion rate reaches more than 15%. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a scanning electron microscope (SEM) image of Na-Ir-W-ITQ-1 synthesized in Example 1 of the present application; Figure 2 This is a high-resolution transmission electron microscopy (TEM) image of Na-Ir-W-ITQ-1 synthesized in Example 1 of the present application. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0020] The preparation process of the catalyst in this application generally includes the following steps: (1) Step 1: Add deionized water and carrier into a glass flask in sequence, and stir at a constant temperature of 50-80 °C for 1-5 h; x m- ) solution was added dropwise to the suspension and stirring was continued for 1 to 5 h.

[0021] The carrier is one of nano-silica, ITQ-1, and ZSM-57; The transition metal anion salt (MO x m- ) is one of (NH4)2WO4, Na2WO4, (NH4)2MoO4, and NaBiO3; The amount of the transition metal anion salt is calculated based on the target loading amount of 0.1 to 5 wt%.

[0022] (2) The second step: a transition metal cation N n+ Add a soluble salt solution to the suspension, adjust the pH to 7-11 with ammonia, and stir at constant temperature for several hours. Cool the mixture to room temperature, filter, and wash the filter cake with deionized water until neutral. Dry the filter cake at 60°C for 3-5 hours.

[0023] The other transition metal cation N n+ Mn 2+ 、Co 2+ 、Ni 2+ 、Cu 2+ 、Ir 3+ One of the salts of which the soluble salt solutions refer to their nitrates, hydrochlorides, and acetates; The amount of the transition metal cation soluble salt is calculated based on the target loading amount of 0 to 5%.

[0024] (3) Step 3: Add the catalyst loaded with two transition metals to a three-necked flask, add deionized water, heat to 40-100°C, stir for 0.5-4 h, add the alkali metal salt solution, continue stirring for 1-12 h, add dilute ammonia water to adjust the pH to 8-11, and continue stirring for 1-5 h. After the mixture is cooled to room temperature, filter it, and wash the filter cake with deionized water until it is neutral. Dry the filter cake at 60°C for 3-5 h, then at 100°C for 3-8 h, and calcine at 450-600°C for 4-6 h to obtain the finished catalyst.

[0025] The alkali metal is one of Li, Na, and K; The alkali metal salt is nitrate, hydrochloride or acetate of the above three alkali metals, and its suitable usage is 0.1-10% of the mass of the carrier.

[0026] Application Example 1 The synthesized catalyst is applied to olefin epoxidation reaction in this application. The reaction apparatus comprises a fixed bed reactor, a stainless steel autoclave, and a normal pressure glass flask. The fixed bed reaction steps include: (1) placing the prepared catalyst in a fixed bed reactor; The fixed bed reactor is a normal pressure or high pressure fixed bed reactor (2) Activate the catalyst with oxygen or air at 100-300 °C for 1-5 h; (3) Cooling to room temperature and replacing the remaining air or oxygen in the fixed bed with the balance gas; The balance gas is nitrogen or argon (4) Introduce olefins, balance gas, and oxygen into the fixed bed to increase the pressure in the fixed bed to 0.1-2.0 MPa; The olefin is propylene; The balance gas is nitrogen or argon; The feed ratio (volume) of the olefin, balance gas, and oxygen is 10:0-100:0.05-2.0, and the preferred feed ratio is 10:1-30:0.5-1.5; The fixed bed pressure is controlled at 0.1~2.0 MPa.

[0027] (5) Gradually increase the temperature in the fixed bed to 90~350℃; The fixed bed heating rate is 5~10℃ / min.

[0028] (6) The reaction materials were sampled from the sampling port and the olefin conversion was analyzed by gas chromatography.

[0029] The gas chromatograph used was a GC9790P3600 gas chromatograph, supplied by Zhejiang Fuli Analytical Instrument Co., Ltd., with a dual detection system consisting of an FID detector and a long-legged TCD detector. The FID detector detected combustible components, while the TCD detector detected non-combustible components such as nitrogen, carbon dioxide, and carbon monoxide. The FID column used a stainless steel packed column, dimensions: 1.5 m x 1 / 8 inch (OD), stationary phase: Porapak Q 60-80 mesh, pre-column pressure: 0.08 MPa, column temperature: 150°C, maximum operating temperature: 250°C. The TCD column used a stainless steel packed column, dimensions: 3 m x 1 / 8 inch (OD), stationary phase: Porapak Q 60-80 mesh, carrier gas flow rate: 30 mL / min, column temperature: 150°C, maximum operating temperature: 250°C.

[0030] The propylene conversion includes the propylene conversion rate and the selectivity of the reaction target product propylene oxide, and the calculation formula is as follows.

[0031] The calculation formula of propylene single-pass conversion rate is: η 丙烯 100% (Formula 1) Propylene oxide (PO) selectivity calculation formula: S PO %……(Formula 2) Where: S PO is propylene oxide selective; PA PO The peak area of ​​propylene oxide (PO) in the reaction mixture; ∑PA C1产物 is the total peak area of ​​all C1 organic products (such as methanol, formaldehyde, formic acid, etc.) at the reactor outlet under stable operation; ∑PA C2产物 is the total peak area of ​​all C2 organic products (such as ethanol, acetaldehyde, acetic acid, etc.) at the reactor outlet under stable operation; ∑PA C3产物 It is the total peak area of ​​all C3 organic products (such as propylene oxide, propanol, propionaldehyde, acrolein, acetone, acrylic acid, propionic acid, etc.) at the reactor outlet under stable operation; PA CO2 is the peak area of ​​carbon dioxide at the reactor outlet under stable operation.

[0032] Application Example 2 The synthesized catalyst is applied to olefin epoxidation reaction in this application. The reaction apparatus comprises a fixed bed reactor, a stainless steel autoclave, and a normal pressure glass flask. The reaction steps in the stainless steel autoclave include: (1) Add the prepared catalyst, solvent, and olefin material into a stainless steel autoclave; The stainless steel autoclave is lined with PTFE; The olefins are cyclohexene, styrene, and 3-chloropropylene; The solvent is one of acetonitrile, tetrahydrofuran, dioxane, cyclohexane, n-heptane, N,N-dimethylformamide (DMF), and N-methylpyrrolidone (NMP); (2) Close the autoclave and perform gas replacement three times with the balance gas; The balance gas is nitrogen or argon; (3) Fill the balance gas cylinder with balance gas to a pressure of 0.15~1.0 MPa; (4) Fill the reactor with oxygen through an oxygen cylinder until the pressure inside the reactor is 0.17~1.2 MPa; (5) Slowly increase the temperature in the reactor to 80~350℃; Here, the heating rate is ≤10 °C / min.

[0033] (6) After a period of reaction, the autoclave is cooled and samples are taken from the sampling port of the autoclave for gas chromatography analysis to determine the reaction conversion rate and selectivity.

[0034] The conversion rate calculation formula of liquid olefin epoxidation reaction is: 100%... (Formula 3) The selectivity calculation formula for liquid olefin epoxidation reaction is: S 环氧 %……(Formula 4) η is the olefin conversion rate; n 0烯烃 is the amount of olefin raw material added (unit: mol), n i烯烃 is the remaining amount of olefin raw materials in the sample (unit: mol), n 环氧 is the amount of epoxidation product generated (unit: mol).

[0035] Example 1: Preparation of Na-Ir-W-ITQ-1 molecular sieve 2.0 g of ITQ-1 molecular sieve was suspended in 20 mL of deionized water and stirred at 100°C for 2 h. An ammonium tungstate solution (calculated based on a target loading of 5 wt%) was added and stirred at 60°C for 3 h. An iridium chloride solution (concentration calculated based on a target loading of 3.1 wt%) was slowly added to the suspension and stirred for 3 h. The pH was adjusted to 9–10 with 1 mol / L ammonia water and stirred at 60°C for 5 h. After cooling to room temperature, the precipitate was ultrasonically treated (40 kHz) for 30 min to promote dispersion. The precipitate was filtered, washed with deionized water until neutral, and dried at 75°C for 3 h.

[0036] The dried Ir-W-ITQ-1 molecular sieve was suspended in 10 mL of deionized water and added NaNO3 The solution (calculated based on a target loading of 0.5 wt%) was stirred at 60°C for 1 h. After filtration, the impregnation was repeated three times. The mixture was filtered and washed with deionized water. The filter cake was dried at 80°C for 5 h and then transferred to a muffle furnace and calcined in a static air atmosphere at 500°C for 5 h to obtain the catalyst Na-Ir-W-ITQ-1.

[0037] Example 2: Preparation of Na-Ir-Mo-SiO2 catalyst Add silica sol to a two-necked flask and stir in a 60°C water bath for 30 minutes to achieve uniform dispersion. Slowly add ammonium molybdate solution dropwise (at a controlled rate of 1 mL / min, based on a target loading of 4%) and continue stirring at 60°C for 3 hours. Slowly add iridium chloride solution dropwise (based on a target loading of 3.4%) to the mixture and stir for 30 minutes. Then, add aqueous ammonia dropwise to adjust the pH to 9–10. Heat to 100°C and reflux with stirring for 5 hours. Cool to room temperature, sonicate at 40 kHz for 30 minutes, filter, and wash with deionized water until neutral. Dry at 75°C for 2 hours.

[0038] The dried Ir-Mo-SiO2 intermediate is immersed in NaNO3 The solution (the amount used is calculated based on a target loading of 1.5%) was heated to 60°C and stirred for 1 hour. 0.5 mol / L ammonia was added dropwise to adjust the pH to 11 and stirring was continued for 5 hours. Filter and wash with deionized water. The filter cake was dried at 80°C for 5 hours and then transferred to a muffle furnace and calcined in a static air atmosphere at 500°C for 6 hours to obtain the final catalyst. Na-Ir-Mo-SiO2 .

[0039] Example 3: Preparation of K-Co-ZSM-57 molecular sieve Suspend ZSM-57 in deionized water, heat to 70°C, stir for 45 min, add cobalt nitrate solution (the amount used is calculated based on the target loading of 3 wt%), and continue stirring for 1 h. Add KOAc solution (the amount used is calculated based on the target loading of 2.6 wt%) dropwise, and continue stirring for 5 h. Filter and wash with deionized water until neutral (avoid K+ The resulting solid was transferred to a muffle furnace and calcined at 550°C in a static air atmosphere for 4 h to obtain the catalyst K-Co-ZSM-57.

[0040] Example 4: Preparation of Na-Ni-W-ITQ-1 molecular sieve The operation was carried out according to Example 1, and the ITQ-1 molecular sieve was treated with the metal precursors ammonium tungstate, nickel nitrate, and sodium chloride in sequence according to the target loading amounts (Na: 1 wt %, Ni: 6 wt %, W: 3 wt %) to obtain a Na-Ni-W-ITQ-1 catalyst.

[0041] Example 5: Fixed-bed propylene epoxidation reaction catalyzed by Na-Ir-W-ITQ-1 molecular sieve An 8 mm diameter quartz reaction tube was loaded with 0.5 g of the Na-Ir-W-ITQ-1 catalyst and placed in a fixed-bed reactor. Oxygen was introduced at 250°C for activation for 3 h. The reactor was cooled and continuously purged with nitrogen for gas replacement. The propylene, oxygen, and nitrogen flow rates were set to 20, 3.5, and 45 mL / min, respectively, using the control console. The reaction pressure was atmospheric pressure, the reactor inlet temperature was set to 80°C, and the furnace temperature was set to 200°C. The nitrogen valve was opened to introduce nitrogen into the reactor. After 5 minutes, the propylene valve was opened to introduce propylene. Another 5 minutes later, the oxygen valve was opened to introduce oxygen. A heating program was initiated, increasing the furnace temperature to 200°C at a rate of 5°C / min. One hour later, the reaction mixture was monitored by online gas chromatography, revealing a propylene conversion of 20.3% and a PO selectivity of 65.2%.

[0042] Example 6 Epoxidation of 3-Propylene Chloride in Autoclave Catalyzed by Na-Ir-W-ITQ-1 Molecular Sieve A 25 mL autoclave was charged with 3 mmol of 3-chloropropene, 10 mL of acetonitrile as solvent, and 0.1 g of the catalyst Na-Ir-W-ITQ-1. The atmosphere was then replaced with argon three times. Argon was introduced to raise the pressure in the autoclave to 1.0 MPa, and oxygen was introduced to maintain the pressure at 1.4 MPa. The autoclave was heated to 100°C via the control console and reacted for 5 hours. Gas chromatography revealed a 3-chloropropene conversion of 48.5% and an epichlorohydrin selectivity of 88.7%.

[0043] Example 7 Styrene Epoxidation Catalyzed by Na-Ni-W-ITQ-1 Molecular Sieve at Normal Pressure To a four-necked glass flask equipped with a magnetic stirrer and a serpentine condenser, 0.05 g of catalyst, 3 mmol of styrene, and 10 mL of N-methylpyrrolidone were added, sequentially. The reaction apparatus was gas-purged three times with nitrogen. An oxygen bulb was connected to the glass tee above the condenser to provide oxygen. The reaction was continued at 100°C for 3 h. Gas chromatography revealed a styrene conversion of 40.6% and a styrene epoxidation selectivity of 90.4%.

[0044] Example 8 Fixed-bed reaction of propylene epoxidation catalyzed by K-Co-ZSM-57 molecular sieve The operation was similar to that in Example 5, except that 0.5 g of catalyst was loaded, the catalyst activation temperature was 300°C, the activation time was 2.5 h, the propylene and oxygen flow rates were set at 85 and 15 mL / min, respectively, the reaction pressure was atmospheric pressure, the reactor inlet temperature was set at 80°C, and the furnace reaction temperature was set at 150°C. After a one-hour reaction, the reaction mixture was monitored by online gas chromatography, revealing a propylene conversion of 21.3% and a PO selectivity of 91.3%.

[0045] Example 9 Na-Ir-Mo-SiO2 catalyzed propylene epoxidation fixed bed reaction The operation was similar to that in Example 5, except that 0.8 g of unactivated catalyst was loaded. The balance gas was argon, and the propylene, oxygen, and argon flow rates were set at 83.5, 16.5, and 100 mL / min, respectively. The reaction pressure was atmospheric pressure, the reactor inlet temperature was set at 80°C, and the furnace temperature was set at 180°C. After a 1-hour reaction, the reaction mixture was monitored by online gas chromatography, revealing a propylene conversion of 9.4% and a PO selectivity of 60.6%.

[0046] Example 10 Fixed-bed propylene epoxidation reaction catalyzed by Na-Mo-ITQ-1 molecular sieve The operation was similar to that in Example 5, except that 0.5 g of catalyst was loaded, the catalyst activation temperature was 300°C, the activation time was 2.5 h, the propylene and oxygen flow rates were set at 85 and 15 mL / min, respectively, the reaction pressure was atmospheric pressure, the reactor inlet temperature was set at 80°C, and the furnace temperature was set at 250°C. After a one-hour reaction, the reaction mixture was monitored by online gas chromatography, revealing a propylene conversion of 10.7% and a PO selectivity of 45.3%.

[0047] Example 11 Fixed-bed propylene epoxidation reaction catalyzed by Li-Mo-ITQ-1 molecular sieve The operation was similar to that in Example 5, except that 0.5 g of catalyst was loaded, the catalyst activation temperature was 300°C, the activation time was 2.5 h, the propylene and oxygen flow rates were set at 85 and 15 mL / min, respectively, the reaction pressure was atmospheric pressure, the reactor inlet temperature was set at 80°C, and the furnace reaction temperature was set at 300°C. After a one-hour reaction, the reaction mixture was monitored by online gas chromatography, revealing a propylene conversion of 0.99% and a PO selectivity of 15.6%.

[0048] The above is only a preferred specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes based on the technical solution and inventive concept of the present application within the technical scope disclosed in the present application, and they should be covered by the scope of protection of the present application.

Claims

1. An enzyme-mimicking multi-metal supported catalyst, characterized by: The multi-metal supported catalyst comprises a carrier, two transition metals and an alkali metal.

2. The enzyme-mimicking multi-metal supported catalyst according to claim 1, characterized in that: The carrier is one of nano-silica, ZSM-57 and ITQ-1 molecular sieve.

3. The enzyme-mimicking multi-metal supported catalyst according to claim 2, characterized in that: Of the two transition metals, one added in the form of a cationic solution is one of manganese (Mn2+), cobalt (Co2+), nickel (Ni2+), copper (Cu2+), and iridium (Ir3+); the other added in the form of a metal anion solution is one of molybdenum (MoO4 2- ), tungsten (WO4 2- ), bismuth (BiO 3- ) is one of the following.

4. The enzyme-mimicking multi-metal supported catalyst according to claim 3, characterized in that: The alkali metal is one of lithium, sodium and potassium.

5. The method for preparing an enzyme-mimicking multi-metal supported catalyst according to claim 4, wherein: The following steps are involved: The carrier is dispersed in deionized water, and a transition metal anion solution is added to the suspension under vigorous stirring. After stirring for several minutes, another transition metal cation solution is added, stirred for several minutes, filtered, washed with deionized water, and dried at 80°C for 3 hours; the obtained solid is suspended in deionized water, an alkali metal ion salt solution is added, stirred for several minutes, ammonia water is added to adjust the pH to 7-11, filtered, washed with deionized water, dried at 60-120°C, and then calcined in a muffle furnace at 300-600°C to obtain a supported catalyst.

6. The method for preparing the enzyme-mimicking multi-metal supported catalyst according to claim 5, characterized in that: The metal loading amount in the supported catalyst is: anion transition metal loading amount is 0.1-5 wt %, cationic transition metal loading amount is 0-5 wt %, and alkali metal loading amount is 0.1-3 wt %.

7. Use of the enzyme-mimicking multimetal supported catalyst according to any one of claims 1 to 6, characterized in that: The catalyst is used in olefin epoxidation reaction.

8. The use of the enzyme-mimicking multi-metal supported catalyst according to claim 7, characterized in that: The olefin is one of propylene, allyl chloride, cyclohexene and styrene, and the oxidant for the epoxidation reaction is oxygen.

9. The use of the enzyme-mimicking multi-metal supported catalyst according to claim 8, characterized in that: The olefin is propylene, and the reaction process is as follows: a catalyst is loaded into a fixed-bed reactor, and propylene, oxygen, and balance gas are introduced into the fixed bed for a heterogeneous reaction, wherein the balance gas is nitrogen or argon; the fixed-bed reaction conditions are a temperature of 80-350°C, a pressure of 0.1-3 MPa, and a feed volume ratio of each gas material of propylene: balance gas: oxygen = 1:0-20:0.1-0.

5.

10. The use of the enzyme-mimicking multi-metal supported catalyst according to claim 8, characterized in that: The olefins are allyl chloride, cyclohexene, and styrene. The reaction process is to add a solvent, an olefin raw material, and a catalyst into a stainless steel autoclave, fill the stainless steel autoclave with oxygen and a balance gas, and react under certain conditions; the solvent is one of acetonitrile, tetrahydrofuran, dioxane, cyclohexane, n-heptane, N,N-dimethylformamide (DMF), and N-methylpyrrolidone (NMP), and the balance gas is nitrogen or argon. The enzyme-mimicking multi-metal supported catalyst is used in the epoxidation reaction of allyl chloride, cyclohexene, and styrene, and the reaction conditions are: temperature 80-350°C and pressure 0.1-5 MPa.

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