Preparation method and application of metal particle confinement porous oxide

Abstract

The invention discloses a preparation method and application of a metal particle confinement porous oxide, relates to the technical field of preparation of thermocatalytic materials, and is used for solving the technical problems of low propylene selectivity of a platinum catalyst and catalyst deactivation caused by high-temperature sintering and coke formation in the existing propane dehydrogenation technology. The preparation method of the metal particle confinement porous oxide comprises the following steps: obtaining a metal target material; the method comprises the following steps: putting a metal target material into an organic solvent, and bombarding the metal target material by adopting a laser beam under an ultrasonic condition to obtain a colloidal solution containing metal particles; adding aldehyde and amine into the colloidal solution, reacting, and washing and drying the precipitate to obtain first powder; dispersing the first powder in an ethanol solution of metal salt, uniformly mixing, concentrating and drying to obtain second powder; calcining the second powder to obtain a metal particle confinement porous oxide; the technical scheme of the invention is used for providing the preparation method and application of the metal particle confinement porous oxide.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal catalytic material preparation, and more specifically, to a preparation method and application of metal particle confined porous oxide. Background Art

[0002] With the rapid development of the global chemical industry, the demand for propylene, as an important basic chemical raw material, continues to grow. Propylene is widely used in the production of various chemicals such as polypropylene, acrylonitrile, propylene oxide, acrylic acid and its esters, and occupies an indispensable position in many industries such as plastics, textiles, medicine, and coatings. However, although traditional propylene production methods, such as steam cracking and fluid catalytic cracking, are mature in technology, they are limited by the source of raw materials and production costs and are difficult to meet the growing market demand for propylene.

[0003] In recent years, propane dehydrogenation (PDH) technology has gradually become the main method for propylene production because of its ability to efficiently utilize abundant shale gas resources and its high selectivity. Shale gas is an unconventional natural gas resource with huge reserves and wide distribution. Its rich propane content provides a stable source of raw materials for propane dehydrogenation to produce propylene. In addition, propane dehydrogenation technology has a high conversion rate and selectivity, and can directly convert propane into propylene, reducing the generation of intermediate links and by-products, thereby improving the production efficiency and economy of propylene.

[0004] However, in the application of propane dehydrogenation technology, the selection and performance of catalysts have become key factors restricting its development. Platinum metal occupies an important position in propane dehydrogenation catalysts due to its excellent catalytic activity. However, under high-temperature propane dehydrogenation reaction conditions, platinum catalysts face technical problems such as reduced propylene selectivity and catalyst deactivation due to high-temperature sintering and coke formation. This not only affects the yield and purity of propylene, but also increases the frequency of catalyst replacement and production costs. Summary of the invention

[0005] The purpose of the present invention is to provide a preparation method and application of metal particle confined porous oxide, which is used to solve the technical problems of low propylene selectivity of platinum catalyst and catalyst deactivation due to high temperature sintering and coke formation in existing propane dehydrogenation technology. In view of this, the present invention provides the following technical solution.

[0006] In a first aspect, the present invention provides a method for preparing a metal particle confined porous oxide, comprising: Obtaining metal target material; The metal target is placed in an organic solvent, and under ultrasonic conditions, a laser beam is used to bombard the metal target to obtain a colloidal solution containing metal particles; the temperature of the organic solvent is -20 to 0°C; adding aldehyde and amine to the colloidal solution, stirring until the reaction is completed, washing and drying the precipitate to obtain a first powder, wherein the first powder is a metal particle confined porous organic framework; Dispersing the first powder in an ethanol solution of a metal salt, mixing evenly, and concentrating and drying to obtain a second powder; The second powder is calcined to obtain a metal particle confined porous oxide; wherein the calcination temperature is 300-650° C. and the calcination time is 4-7 hours.

[0007] Compared with the prior art, in the preparation method of the metal particle confined porous oxide of the present invention, a colloidal solution containing metal particles can be obtained by bombarding a metal target with a laser beam. In this process, by controlling the temperature of the organic solvent to -20~0°C and carrying out under ultrasonic conditions, the metal particles obtained by bombarding the metal target with a laser beam can be prevented from agglomerating or aggregating in the organic solvent. Aldehydes and amines are added to the colloidal solution, and the aldehydes and amines react in the colloidal solution, and the precipitate is washed and dried to obtain a metal particle confined porous organic framework, in which the loading amount of metal particles can be as high as 15wt%. Further, using the porous organic framework as a template, the porous organic framework (first powder) is dispersed in an ethanol solution of a metal salt, and the metal salt will penetrate into the porous organic framework to obtain a second powder. Further, the second powder is calcined to remove the porous organic framework, thereby obtaining a metal particle confined porous oxide. In the above process, for example, the temperature of the organic solvent can be -20°C, -10°C or 0°C, the temperature of the calcination treatment is 300°C, 400°C, 550°C or 650°C, and the calcination time can be 4 hours, 5 hours, 6 hours or 7 hours. The metal particle confined porous oxide prepared by the present invention can provide a large number of active sites for the catalytic process, and is used for the propane dehydrogenation reaction to produce propylene. It has a high propane conversion rate and propylene selectivity, and will not sinter or form coke under high temperature conditions. The technical solution of the present invention solves the technical problems of low propylene selectivity of platinum catalysts and catalyst deactivation due to high-temperature sintering and coke formation in the existing propane dehydrogenation technology.

[0008] Furthermore, in the method for preparing the metal particle confined porous oxide of the present invention, the content of the metal particles in the colloidal solution is 0.0001-0.0015 g / ml; and / or, The laser beam is a nanosecond pulse laser beam, and the laser flux of the nanosecond pulse laser beam is 600-2000mJpulse -1 cm -1 , the bombardment time of the metal target is 2 to 15 minutes.

[0009] Furthermore, in the method for preparing the metal particle confined porous oxide of the present invention, the metal includes one or any two of platinum, silver, palladium, gold, gallium, cobalt, nickel, copper, iron, zinc and tin.

[0010] Furthermore, in the method for preparing the metal particle confined porous oxide of the present invention, the organic solvent includes n-butanol, methanol, ethanol, dimethyl sulfoxide, dioxane, N,N-dimethylformamide and N,N-dimethylacetamide.

[0011] Furthermore, in the preparation method of the metal particle confined porous oxide of the present invention, the aldehyde includes terephthalaldehyde, substituted terephthalaldehyde, isophthalic acid trimeraldehyde, biphenyl dicarboxaldehyde, substituted biphenyl dicarboxaldehyde, terphenyl dicarboxaldehyde, substituted terphenyl dicarboxaldehyde and trialdehyde phloroglucinol; and / or, The amines include p-phenylenediamine, substituted p-phenylenediamine, benzylenediamine, substituted benzylenediamine, terphenylenediamine, substituted terphenylenediamine and 1,3,5-triaminobenzene.

[0012] Furthermore, in the method for preparing the metal particle confined porous oxide of the present invention, the step of adding aldehyde and amine to the colloidal solution comprises: 0.01 mol of aldehyde and 0.01 mol of amine were added to every 200 ml of the colloidal solution.

[0013] Furthermore, in the preparation method of the metal particle confined porous oxide of the present invention, in the process of adding aldehyde and amine to the colloidal solution and stirring until the reaction is completed, the reaction temperature is 60-80° C. and the reaction time is 12-72 hours.

[0014] Furthermore, in the method for preparing the metal particle confined porous oxide of the present invention, the metal salt comprises aluminum nitrate, aluminum chloride, cerium nitrate, ammonium cerium nitrate, cerium chloride, zirconium nitrate and zirconium acetate; and / or, In the ethanol solution of the metal salt, the mass ratio of the metal salt to ethanol is 1:(35-50).

[0015] In a second aspect, the present invention provides a metal particle confined porous oxide, which is prepared using the above-mentioned method for preparing the metal particle confined porous oxide.

[0016] Compared with the prior art, the beneficial effects of the metal particle confined porous oxide of the present invention are the same as the beneficial effects of the method for preparing the metal particle confined porous oxide described in the above technical solution, and will not be repeated here.

[0017] In a third aspect, the present invention provides the use of the above-mentioned metal particle confined porous oxide in the dehydrogenation of propane to produce propylene. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 is an X-ray diffraction pattern of the Pt metal particle confined porous organic framework powder in Example 1 of the present invention; Figure 2 is an X-ray diffraction pattern of the Pt metal particle confined porous alumina in Example 1 of the present invention; Figure 3 is an X-ray diffraction pattern of the Pt metal particle-confined porous cerium oxide in Example 2 of the present invention; Figure 4 This is an X-ray photoelectron spectrum of the Pt metal particle confined porous organic framework powder in Example 1 of the present invention; Figure 5 This is an X-ray photoelectron spectrum of the Pt metal particle confined porous alumina in Example 1 of the present invention; Figure 6 This is an X-ray photoelectron spectrum of the Pt metal particle confined porous cerium oxide in Example 2 of the present invention; Figure 7 This is a high-angle annular dark-field scanning transmission electron microscopy image of the Pt metal particle confined porous organic framework in Example 1 of the present invention corrected for spherical aberration; Figure 8 This is a high-angle annular dark field scanning transmission electron microscope image of the Pt metal particle-confined porous alumina in Example 1 of the present invention; Fig. 9 This is a high-angle annular dark-field scanning transmission electron microscope image of the porous cerium oxide confined by Pt metal particles in Example 2 of the present invention; Fig.10 This is a performance diagram of direct dehydrogenation of propane of the Pt metal particle confined porous alumina composite catalytic material in Example 1 of the present invention; Fig.11 This is a performance diagram of CO2-assisted propane oxidative dehydrogenation of the Pt metal particle confined porous cerium oxide composite catalytic material in Example 2 of the present invention. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0020] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0021] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The meaning of "several" is one or more, unless otherwise clearly and specifically defined.

[0022] In recent years, propane dehydrogenation (PDH) technology has gradually become the main method for propylene production because of its ability to efficiently utilize abundant shale gas resources and its high selectivity. Shale gas, as an unconventional natural gas resource, has huge reserves and is widely distributed. Its rich propane content provides a stable source of raw materials for propane dehydrogenation to produce propylene. In addition, propane dehydrogenation technology has a high conversion rate and selectivity, and can directly convert propane into propylene, reducing the generation of intermediate links and by-products, thereby improving the production efficiency and economy of propylene. However, in the application of propane dehydrogenation technology, the selection and performance of catalysts have become key factors restricting its development. Platinum metal occupies an important position in propane dehydrogenation catalysts due to its excellent catalytic activity. However, under high-temperature propane dehydrogenation reaction conditions, platinum catalysts face technical problems such as reduced propylene selectivity and catalyst deactivation caused by high-temperature sintering and coke formation. Not only does it affect the yield and purity of propylene, but it also increases the frequency of catalyst replacement and production costs.

[0023] In order to solve the above technical problems, in a first aspect, the present invention provides a method for preparing a metal particle confined porous oxide, comprising: Obtaining metal target material; The metal target is placed in an organic solvent, and under ultrasonic conditions, a laser beam is used to bombard the metal target to obtain a colloidal solution containing metal particles; the temperature of the organic solvent is -20 to 0°C; adding aldehyde and amine to the colloidal solution, stirring until the reaction is completed, washing and drying the precipitate to obtain a first powder, wherein the first powder is a metal particle confined porous organic framework; Dispersing the first powder in an ethanol solution of a metal salt, mixing evenly, and concentrating and drying to obtain a second powder; The second powder is calcined to obtain a metal particle confined porous oxide; wherein the calcination temperature is 300-650° C. and the calcination time is 4-7 hours.

[0024] In the case of adopting the above technical scheme, compared with the prior art, in the preparation method of the metal particle confined porous oxide of the present invention, a colloidal solution containing metal particles can be obtained by bombarding a metal target with a laser beam. In this process, by controlling the temperature of the organic solvent to -20~0°C and carrying out under ultrasonic conditions, the metal particles obtained by bombarding the metal target with a laser beam can be prevented from agglomerating or aggregating in the organic solvent. Aldehydes and amines are added to the colloidal solution, and the aldehydes and amines react in the colloidal solution, and the precipitate is washed and dried to obtain a metal particle confined porous organic framework, in which the loading amount of metal particles can be as high as 15wt%. Further, using the porous organic framework as a template, the porous organic framework (first powder) is dispersed in an ethanol solution of a metal salt, and the metal salt will penetrate into the porous organic framework to obtain a second powder. Further, the second powder is calcined to remove the porous organic framework, thereby obtaining a metal particle confined porous oxide. In the above process, for example, the temperature of the organic solvent can be -20°C, -10°C or 0°C, the temperature of the calcination treatment is 300°C, 400°C, 550°C or 650°C, and the calcination time can be 4 hours, 5 hours, 6 hours or 7 hours. The metal particle confined porous oxide prepared by the present invention can provide a large number of active sites for the catalytic process, and is used for the propane dehydrogenation reaction to produce propylene. It has a high propane conversion rate and propylene selectivity, and will not sinter or form coke under high temperature conditions. The technical solution of the present invention solves the technical problems of low propylene selectivity of platinum catalysts and catalyst deactivation due to high-temperature sintering and coke formation in the existing propane dehydrogenation technology.

[0025] It should be understood that in the preparation method of the metal particle confined porous oxide of the present invention, the content of metal particles in the colloidal solution can be controlled by controlling the laser flux of the laser beam and the time of bombarding the metal target. For example, the laser beam can be a nanosecond pulse laser beam, and the laser flux of the nanosecond pulse laser beam is 600-2000mJpulse -1 cm -1 The time for bombarding the metal target is 2 to 15 minutes. In another example, the laser flux of the nanosecond pulse laser beam is 600 mJ pulse. - 1 cm -1 、1000mJpulse -1 cm -1 、15000mJpulse -1 cm -1or 2000mJpulse -1 cm -1 For example, the content of metal particles in the colloidal solution may be 0.0001-0.0015 g / ml.

[0026] It should also be understood that in the preparation method of the metal particle confined porous oxide of the present invention, the prepared metal particle confined porous oxide is used for the propane dehydrogenation to propylene reaction. In order to further improve the propane conversion rate and propylene selectivity, it is also necessary to control the types of metals and organic solvents. For example, the metal includes one or any two of platinum, silver, palladium, gold, gallium, cobalt, nickel, copper, iron, zinc and tin. For another example, the metal can be platinum, silver, palladium, gold, gallium, cobalt, nickel, copper, iron, zinc or tin, or platinum and silver, platinum and tin, platinum and gallium, cobalt and nickel, and gallium and zinc. For example, the organic solvent includes n-butanol, methanol, ethanol, dimethyl sulfoxide, dioxane, N,N dimethylformamide and N,N dimethylacetamide; for another example, the organic solvent can be n-butanol, methanol, ethanol, dimethyl sulfoxide, dioxane, N,N dimethylformamide or N,N dimethylacetamide.

[0027] It should also be understood that in the preparation method of the metal particle confined porous oxide of the present invention, different aldehydes and amines have different chemical structures and reactivity. By selecting specific aldehydes and amines, the reaction conditions can be optimized to improve the yield and purity of the target product; further, the types of aldehydes and amines will also directly affect the void structure of the porous organic framework, thereby affecting the structure and performance of the subsequent porous oxide, and the confinement effect of the metal particles in the porous organic framework will also be affected by the specific types of aldehydes and amines. Therefore, in order to obtain a porous organic framework with a better structure, the types of aldehydes and amines need to be controlled in the present invention. For example, the aldehydes include terephthalaldehyde, substituted terephthalaldehyde, trimeraldehyde, biphenyldiformaldehyde, substituted biphenyldiformaldehyde, terphenyldiformaldehyde, substituted terphenyldiformaldehyde and trialdehyde phloroglucinol; the amines include p-phenylenediamine, substituted p-phenylenediamine, biphenyldiamine, substituted biphenyldimethylamine, terphenyldimethylamine, substituted terphenyldimethylamine and 1,3,5-triaminobenzene. As another example, the aldehyde can be terephthalaldehyde, substituted terephthalaldehyde, isophthalaldehyde, biphenyldicarboxaldehyde, substituted biphenyldicarboxaldehyde, terphenyldicarboxaldehyde, substituted terphenyldicarboxaldehyde or trialdehyde phloroglucinol; the amine can be p-phenylenediamine, substituted p-phenylenediamine, biphenyldiamine, substituted biphenyldimethylamine, terphenyldimethylamine, substituted terphenyldimethylamine or 1,3,5-triaminobenzene.

[0028] It should also be understood that in the preparation method of the metal particle confined porous oxide of the present invention, in order to improve the generation rate and purity of the target product (i.e., the porous organic framework), in the process of adding aldehyde and amine to the colloidal solution, it is also necessary to control the mixing ratio of the colloidal solution to the aldehyde and amine within a reasonable range; for example, 0.01 mol of aldehyde and 0.01 mol of amine can be added to 200 ml of the colloidal solution.

[0029] It should also be understood that in the preparation method of the metal particle confined porous oxide of the present invention, in order to add aldehyde and amine to the colloidal solution, in order to make the aldehyde and amine react completely and obtain a porous organic framework with a better structure, it is also necessary to control the reaction temperature and reaction time within a reasonable range; illustratively, the reaction temperature can be 60~80℃, and the reaction time can be 12~72 hours; as another example, the reaction temperature can be 60℃, 70℃ or 80℃, and the reaction time can be 12 hours, 24 hours, 48 ​​hours or 72 hours.

[0030] It should also be understood that in the preparation method of the metal particle confined porous oxide of the present invention, the prepared metal particle confined porous oxide is used for the propane dehydrogenation reaction to produce propylene. In order to further improve the propane conversion rate and propylene selectivity, the type of metal salt should also be controlled. By way of example, the metal salt includes aluminum nitrate, aluminum chloride, cerium nitrate, ammonium cerium nitrate, cerium chloride, zirconium nitrate and zirconium acetate; by way of another example, the metal salt can be aluminum nitrate, aluminum chloride, cerium nitrate, ammonium cerium nitrate, cerium chloride, zirconium nitrate or zirconium acetate.

[0031] It should also be understood that in the preparation method of the metal particle confined porous oxide of the present invention, the first powder is dispersed in the ethanol solution of the metal salt, mixed evenly, and then concentrated and dried to obtain the second powder. In order to make the first powder evenly dispersed in the ethanol solution of the metal salt and prepare a porous oxide with higher propylene selectivity, it is also necessary to control the mass ratio of the metal salt to ethanol within a reasonable range; illustratively, the mass ratio of the metal salt to ethanol is 1: (35~50); as another example, the mass ratio of the metal salt to ethanol can be 1:35, 1:40 or 1:50.

[0032] In a second aspect, the present invention further provides a metal particle confined porous oxide, which is prepared using the preparation method of the metal particle confined porous oxide described in the above technical solution.

[0033] In the case of adopting the above technical scheme, the metal particle confined porous oxide of the present invention is prepared by the preparation method of the metal particle confined porous oxide described in the above technical scheme. In the preparation method, a colloidal solution containing metal particles can be obtained by bombarding a metal target with a laser beam. In this process, by controlling the temperature of the organic solvent to -20~0°C and carrying out under ultrasonic conditions, the metal particles obtained by bombarding the metal target with a laser beam can be prevented from agglomerating or aggregating in the organic solvent. Aldehydes and amines are added to the colloidal solution, and the aldehydes and amines react in the colloidal solution, and the precipitate is washed and dried to obtain a metal particle confined porous organic framework, in which the loading amount of metal particles can be as high as 15wt%. Further, using the porous organic framework as a template, the porous organic framework (first powder) is dispersed in an ethanol solution of a metal salt, and the metal salt will penetrate into the porous organic framework to obtain a second powder. Further, the second powder is calcined to remove the porous organic framework, thereby obtaining a metal particle confined porous oxide. The metal particle confined porous oxide prepared by the present invention can provide a large number of active sites for the catalytic process, and is used for the propane dehydrogenation reaction to produce propylene. It has a high propane conversion rate and propylene selectivity, and reduces the formation of sintering or coke under high temperature conditions.

[0034] In a third aspect, the present invention provides the use of the above-mentioned metal particle confined porous oxide in the dehydrogenation of propane to produce propylene.

[0035] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with specific embodiments, but the content of the present invention is not limited to the following embodiments.

[0036] Unless otherwise specified, the raw materials used in the following examples are commercially available. Example 1

[0037] This embodiment provides a method for preparing a metal particle confined porous oxide, comprising: S100, obtaining a polished metal platinum (Pt) sheet, the platinum sheet having a size of 2 cm×2 cm and a thickness of 2 cm; S200, the platinum sheet was placed in a glass bottle containing 10 ml of dimethyl sulfoxide, and the glass bottle was fixed in an ultrasonic machine with 0°C water circulation. Under continuous ultrasonic conditions, a laser flux of 1.0 mJ pulse was used. -1 cm -2 The platinum sheet was bombarded with a nanosecond pulse laser beam (Nd:YAG) for 15 minutes to prepare a Pt metal particle colloidal solution; the Pt metal content in the Pt metal particle colloidal solution was 0.0005 g / ml; S300, 1.08 g of p-phenylenediamine (0.01 mol) and 1.34 g of terephthalaldehyde (0.01 mol) were dispersed in 200 ml of the Pt metal particle colloidal solution of step S200, and ultrasonically treated for 30 min to make them dispersed evenly, and then placed in an oil bath, stirred at 60 ° C for 72 h to complete the reaction, and the stirring rate was 700 rpm; S400, after the reaction in step S300 is completed, a precipitate is formed. After the precipitate is centrifuged, it is washed three times with N, N-dimethylformamide and ethanol respectively, and then placed in an oven at 60° C. to dry overnight (dry for 12 hours) to obtain a first powder, that is, a Pt metal particle confined porous organic framework; S500, dispersing 2 g of the first powder obtained in step S400 in 100 ml of ethanol solution containing 2.25 g of aluminum nitrate nonahydrate, ultrasonicating for 30 min to make it evenly dispersed, and then rotary evaporating at 60° C. and drying overnight (drying for 12 hours) to obtain a second powder; S600, placing the second powder in step S500 in a muffle furnace, heating it to 600°C in air, and calcining it at 600°C for 6 hours, then cooling it to room temperature to obtain a light grey powder, i.e., a Pt metal particle confined porous alumina composite catalytic material; wherein the heating rate is 2°C / min. Example 2

[0038] This embodiment provides a method for preparing a metal particle confined porous oxide, comprising: S100, obtaining a polished metal platinum (Pt) sheet, the platinum sheet having a size of 2 cm×2 cm and a thickness of 2 cm; S200, the platinum sheet was placed in a glass bottle containing 10 ml of n-butanol, and the glass bottle was fixed in an ultrasonic machine with water circulation at -10°C. Under continuous ultrasonic conditions, a laser flux of 1.5 mJ pulse was used. -1 cm -2 The platinum sheet was bombarded with a nanosecond pulse laser beam (Nd:YAG) for 10 minutes to prepare a Pt metal particle colloidal solution; the Pt metal content in the Pt metal particle colloidal solution was 0.0003 g / ml; S300, 1.08 g of p-phenylenediamine (0.01 mol) and 1.34 g of terephthalaldehyde (0.01 mol) were dispersed in 200 ml of the Pt metal particle colloidal solution of step S200, and ultrasonically treated for 30 min to make them dispersed evenly, and then placed in an oil bath, stirred at 60 ° C for 48 h to complete the reaction, and the stirring rate was 800 rpm; S400, after the reaction in step S300 is completed, a precipitate is formed. After the precipitate is centrifuged, it is washed three times with N, N-dimethylformamide and ethanol respectively, and then placed in an oven at 60° C. to dry overnight (dry for 10 hours) to obtain a first powder, that is, a Pt metal particle confined porous organic framework; S500, dispersing 2 g of the first powder obtained in step S400 in 100 ml of ethanol solution containing 2 g of cerium nitrate hexahydrate, ultrasonicating for 30 min to make it evenly dispersed, and then rotary evaporating at 60° C. and drying overnight (drying for 12 hours) to obtain a second powder; S600, placing the second powder in step S500 in a muffle furnace, heating it to 350°C in air, and calcining it at 350°C for 5 hours, then cooling it to room temperature to obtain a light grey powder, i.e., a Pt metal particle confined porous cerium oxide composite catalytic material; wherein the heating rate is 2°C / min. Example 3

[0039] This embodiment provides a method for preparing a metal particle confined porous oxide, comprising: S100, obtaining a polished metal platinum (Pt) sheet, the platinum sheet having a size of 2 cm×2 cm and a thickness of 2 cm; S200, the platinum sheet was placed in a glass bottle containing 10 ml of ethanol, and the glass bottle was fixed in an ultrasonic machine with -20°C water circulation. Under continuous ultrasonic conditions, a laser flux of 1.2 mJ pulse was used. -1 cm -2 The platinum sheet was bombarded with a nanosecond pulse laser beam (Nd:YAG) for 5 minutes to prepare a Pt metal particle colloidal solution; the Pt metal content in the Pt metal particle colloidal solution was 0.001 g / ml; S300, 1.08 g of p-phenylenediamine (0.01 mol) and 1.34 g of terephthalaldehyde (0.01 mol) were dispersed in 200 ml of the Pt metal particle colloidal solution of step S200, and ultrasonically treated for 30 min to make them evenly dispersed, and then placed in an oil bath, stirred at 60 ° C for 72 h to complete the reaction, and the stirring rate was 500 rpm; S400, after the reaction in step S300 is completed, a precipitate is formed. After the precipitate is centrifuged, it is washed three times with N, N-dimethylformamide and ethanol respectively, and then placed in an oven at 60° C. to dry overnight (dry for 10 hours) to obtain a first powder, that is, a Pt metal particle confined porous organic framework; S500, dispersing 2 g of the first powder obtained in step S400 in 100 ml of ethanol solution containing 1.8 g of zirconium nitrate pentahydrate, ultrasonicating for 30 min to make it evenly dispersed, and then rotary evaporating at 60° C. and drying overnight (drying for 12 hours) to obtain a second powder; S600, placing the second powder in step S500 in a muffle furnace, heating it to 350°C in air, and calcining it at 350°C for 5 hours, then cooling it to room temperature to obtain a light grey powder, i.e., a Pt metal particle confined porous zirconia composite catalytic material; wherein the heating rate is 2°C / min. Example 4

[0040] This embodiment provides a method for preparing a metal particle confined porous oxide, comprising: S100, obtaining a polished metal tin (Sn) sheet, the specification of which is 2 cm×2 cm and the thickness is 2 cm; S200, the tin sheet was placed in a glass bottle containing 10 ml of dimethyl sulfoxide, and the glass bottle was fixed in an ultrasonic machine with -5°C water circulation. Under continuous ultrasonic conditions, a laser flux of 0.6 mJ pulse was used. -1 cm -2 The tin sheet was bombarded with a nanosecond pulse laser beam (Nd:YAG) for 1 minute to prepare a Sn metal particle colloidal solution; the Sn metal particle colloidal solution had a Sn content of 0.0015 g / ml; S300, 1.08 g of p-phenylenediamine (0.01 mol) and 2.1 g of trialdehyde phloroglucinol (0.01 mol) were dispersed in 200 ml of the Sn metal particle colloidal solution of step S200, ultrasonically treated for 30 min to make it evenly dispersed, and then placed in an oil bath, stirred at 60 ° C for 72 h to complete the reaction, and the stirring rate was 800 rpm; S400, after the reaction in step S300 is completed, a precipitate is formed. After the precipitate is centrifuged, it is washed three times with N, N-dimethylformamide and ethanol respectively, and then placed in an oven at 60° C. to dry overnight (dry for 12 hours) to obtain a first powder, that is, a Sn metal particle confined porous organic framework; S500, dispersing 2 g of the first powder obtained in step S400 in 100 ml of ethanol solution containing 2.25 g of aluminum nitrate nonahydrate, ultrasonicating for 30 min to make it evenly dispersed, and then rotary evaporating at 60° C. and drying overnight (drying for 12 hours) to obtain a second powder; S600, placing the second powder in step S500 in a muffle furnace, heating it to 600°C in air, and calcining it at 600°C for 6 hours, then cooling it to room temperature to obtain a light grey powder, i.e., a Sn metal particle confined porous alumina composite catalytic material; wherein the heating rate is 2°C / min. Example 5

[0041] This embodiment provides a method for preparing a metal particle confined porous oxide, comprising: S100, obtaining a polished nickel (Ni) sheet, the nickel sheet having a size of 2 cm×2 cm and a thickness of 2 cm; S200, the nickel sheet was placed in a glass bottle containing 10 ml of n-butanol, and the glass bottle was fixed in an ultrasonic machine with -10 °C water circulation. Under continuous ultrasonic conditions, a laser flux of 1.2 mJ pulse was used. -1 cm -2 The nickel sheet was bombarded with a nanosecond pulsed laser beam (Nd:YAG) for 1 minute to prepare a Ni metal particle colloidal solution; the Ni metal particle colloidal solution had a Ni content of 0.0008 g / ml; S300, 1.77 g of dichloro-p-phenylenediamine (0.01 mol) and 1.63 g of isophthalic acid trimeraldehyde (0.01 mol) were dispersed in 200 ml of the Ni metal particle colloidal solution of step S200, and ultrasonically treated for 30 min to make it evenly dispersed, and then placed in an oil bath, stirred at 60 ° C for 72 h to complete the reaction, and the stirring rate was 700 rpm; S400, after the reaction in step S300 is completed, a precipitate is formed. After the precipitate is centrifuged, it is washed three times with N, N-dimethylformamide and ethanol respectively, and then placed in an oven at 60° C. to dry overnight (dry for 10 hours) to obtain a first powder, that is, a Ni metal particle confined porous organic framework; S500, dispersing 2 g of the first powder obtained in step S400 in 100 ml of ethanol solution containing 2 g of cerium nitrate hexahydrate, ultrasonicating for 30 min to make it evenly dispersed, and then rotary evaporating at 60° C. and drying overnight (drying for 12 hours) to obtain a second powder; S600, placing the second powder in step S500 in a muffle furnace, heating it to 600°C in air, and calcining it at 600°C for 6 hours, then cooling it to room temperature to obtain a light gray powder, that is, obtaining a Ni metal particle-confined porous cerium oxide composite catalytic material; wherein the heating rate is 2°C / min. Example 6

[0042] This embodiment provides a method for preparing a metal particle confined porous oxide, comprising: S100, obtaining a polished metal cobalt (Co) sheet, the cobalt sheet having a size of 2 cm×2 cm and a thickness of 2 cm; S200, the cobalt sheet was placed in a glass bottle containing 10 ml of dimethyl sulfoxide, and the glass bottle was fixed in an ultrasonic machine with 0°C water circulation. Under continuous ultrasonic conditions, a laser flux of 1.0 mJ pulse was used. -1 cm -2 The cobalt sheet was bombarded with a nanosecond pulse laser beam (Nd:YAG) for 5 minutes to prepare a Co metal particle colloidal solution; the Co metal content in the Co metal particle colloidal solution was 0.0012 g / ml; S300, 1.08 g of p-phenylenediamine (0.01 mol) and 1.34 g of terephthalaldehyde (0.01 mol) were dispersed in 200 ml of the Co metal particle colloidal solution of step S200, ultrasonically treated for 40 min to make them evenly dispersed, and then placed in an oil bath, stirred at 60 ° C for 72 h to complete the reaction, and the stirring rate was 700 rpm; S400, after the reaction in step S300 is completed, a precipitate is formed. After the precipitate is centrifuged, it is washed three times with N, N-dimethylformamide and ethanol respectively, and then placed in an oven at 80° C. to dry overnight (dry for 12 hours) to obtain a first powder, that is, a Co metal particle confined porous organic framework; S500, dispersing 2 g of the first powder obtained in step S400 in 100 ml of ethanol solution containing 1.8 g of zirconium nitrate pentahydrate, ultrasonicating for 30 min to make it evenly dispersed, and then rotary evaporating at 60° C. and drying overnight (drying for 12 hours) to obtain a second powder; S600, placing the second powder in step S500 in a muffle furnace, heating it to 350°C in air, and calcining it at 350°C for 5 hours, then cooling it to room temperature to obtain a light grey powder, i.e., a Co metal particle confined porous zirconia composite catalytic material; wherein the heating rate is 2°C / min. Example 7

[0043] This embodiment provides a method for preparing a metal particle confined porous oxide, comprising: S100, obtaining a polished metal platinum (Pt) sheet and a metal tin (Sn) sheet, wherein the specifications of the platinum sheet and the tin sheet are both 2 cm×2 cm and 2 cm thick; S200, the platinum sheet was placed in a glass bottle containing 10 ml of dimethyl sulfoxide, and the glass bottle was fixed in an ultrasonic machine with 0°C water circulation. Under continuous ultrasonic conditions, a laser flux of 1.0 mJ pulse was used. -1 cm -2The platinum sheet was bombarded with a nanosecond pulse laser beam (Nd:YAG) for 5 minutes to prepare a colloidal solution of Pt metal particles; The tin sheet was then placed in a glass bottle containing 10 ml of dimethyl sulfoxide, and the glass bottle was fixed in an ultrasonic machine with -5°C water circulation. Under continuous ultrasonic conditions, a laser flux of 0.6 mJ pulse was used. -1 cm -2 The tin sheet was bombarded with a nanosecond pulse laser beam (Nd:YAG) for 5 minutes to prepare a colloidal solution of Sn metal particles; The content of metal Pt in the colloidal solution of Pt metal particles is 0.0003 g / ml, and the content of metal Sn in the colloidal solution of Sn metal particles is 0.001 g / ml; S300, mixing 100 ml of the Pt metal particle colloidal solution and 100 ml of the Sn metal particle colloidal solution in step S200 to obtain a mixed colloidal solution; dispersing 1.08 g of p-phenylenediamine (0.01 mol) and 1.34 g of terephthalaldehyde (0.01 mol) in 200 ml of the mixed colloidal solution respectively, ultrasonically treating the mixed colloidal solution for 30 min to make it uniformly dispersed, placing the mixed colloidal solution in an oil bath, stirring the mixed colloidal solution at 60° C. for 72 h to complete the reaction, and stirring the mixed colloidal solution at a rate of 700 rpm; S400, after the reaction in step S300 is completed, a precipitate is formed. After the precipitate is centrifuged, it is washed three times with N, N-dimethylformamide and ethanol respectively, and then placed in an oven at 60° C. to dry overnight (dry for 12 hours) to obtain a first powder, that is, a PtSn metal particle confined porous organic framework; S500, dispersing 2 g of the first powder obtained in step S400 in 100 ml of ethanol solution containing 2.4 g of aluminum nitrate hexahydrate, ultrasonicating for 30 min to make it evenly dispersed, and then rotary evaporating at 60° C. and drying overnight (drying for 12 hours) to obtain a second powder; S600, placing the second powder in step S500 in a muffle furnace, heating it to 600°C in air, and calcining it at 600°C for 6 hours, then cooling it to room temperature to obtain a light grey powder, i.e., a PtSn metal particle confined porous alumina composite catalytic material; wherein the heating rate is 2°C / min.

[0044] Through the above-mentioned Examples 1 to 7, the present invention respectively prepared Pt metal particles confined porous alumina composite catalytic materials, Pt metal particles confined porous cerium oxide composite catalytic materials, Pt metal particles confined porous zirconia composite catalytic materials, Sn metal particles confined porous alumina composite catalytic materials, Ni metal particles confined porous cerium oxide composite catalytic materials, Co metal particles confined porous zirconia composite catalytic materials, and PtSn metal particles confined porous alumina composite catalytic materials. The following will take Examples 1 and 2 as examples, combined with the attached Figure 1 To Attachment Fig.11 Explanation: From Figure 1 It can be seen that the porous organic framework (POFs) was successfully synthesized in Example 1, and the Pt metal particle confined porous organic framework (Pt@POF) obtained in Example 1 has excellent crystallinity and ordered structure; in addition, the characteristic diffraction peak of Pt (platinum) (PDF#04-0802) can be seen, proving that the Pt particles are highly uniformly distributed in the pores of the porous organic framework POFs. The present invention provides a feasible, simple and efficient strategy for in-situ implantation of metal active catalysts. Figure 2 It can be seen that the Pt metal particle confined porous alumina (Pt@Al2O3) composite catalytic material of Example 1 does not have a strong diffraction peak of alumina, indicating that the alumina carrier is amorphous, and a clear Pt diffraction peak can be observed (PDF#04-0802), proving that Pt was successfully implanted into the alumina carrier by using the composite material of Pt particle confined organic framework (POF) as a template. Figure 3 It can be seen that the Pt metal particle confined porous cerium oxide (Pt@CeO2) composite catalytic material of Example 2 has a strong diffraction peak of cerium oxide, and the Pt diffraction peak is not obvious, indicating that the smaller Pt particles are successfully confined uniformly in the cerium oxide carrier. Figure 4 It can be seen that the peaks at 73.1 eV and 76.4 eV in the XPS spectrum of Pt4f are attributed to Pt in the Pt@POF composite material. 2+ , proving that Pt was successfully implanted into the POF carrier. Figure 5 It can be seen that Pt 4f 5 / 2 overlaps with Al 2p (74.5 eV), while the peak at 71.2 eV corresponds to Pt 4f 7 / 2 , which also proves that Pt is successfully implanted into the alumina support. Figure 6 It can be seen that the peaks at 73.1 eV and 76.4 eV in the XPS spectrum of Pt 4f are attributed to the Pt δ+ (δ<2), proving that Pt was successfully implanted into the cerium oxide carrier. Figure 7 It can be seen that the Pt particles in the Pt metal particle confined porous organic framework (Pt@POF) are highly uniformly dispersed. Figure 8 It can be seen that the Pt particles are evenly distributed in the alumina support. Fig. 9 It can be seen that the Pt particles are evenly distributed within the ceria support.

[0045] Still taking the Pt metal particle confined porous alumina (Pt@Al2O3) composite catalytic material and the Pt metal particle confined porous cerium oxide (Pt@CeO2) composite catalytic material prepared in the above-mentioned Example 1 and Example 2 as examples, the Pt metal particle confined porous alumina (Pt@Al2O3) composite catalytic material and the Pt metal particle confined porous cerium oxide (Pt@CeO2) composite catalytic material are respectively applied to the dehydrogenation of propane to produce propylene. For example, the Pt metal particle confined porous alumina (Pt@Al2O3) composite catalytic material (hereinafter referred to as the first catalyst) of Example 1 is applied to the dehydrogenation of propane to produce propylene: 0.3g of the first catalyst is evenly mixed with 0.7g of 40-60 mesh quartz sand, and then loaded into a fixed bed reactor, and reactants (propane: argon = 5:15ml / min) are introduced at 600°C to carry out a direct dehydrogenation reaction of propane, from Fig.10 It can be seen that the initial propane conversion rate and propylene selectivity of the Pt metal particle confined porous alumina (Pt@Al2O3) composite catalytic material (first catalyst) are 37.36% and 97.22%, respectively. After 2160 minutes of catalysis, the propane conversion rate and propylene selectivity can still be maintained at 10% and 96.7%, respectively. This proves that the Pt particle confined porous alumina (Pt@Al2O3) composite catalytic material synthesized using the porous organic framework as a template has high selectivity and high stability, which strongly proves the high efficiency and feasibility of the technical solution of the present invention.

[0046] As another example, the Pt metal particle confined porous cerium oxide (Pt@CeO2) composite catalytic material (hereinafter referred to as the second catalyst) of Example 2 is applied to propane dehydrogenation to propylene: 0.3g of the second catalyst is mixed evenly with 0.7g of 40-60 mesh quartz sand, loaded into a fixed bed reactor, and reactants (propane: carbon dioxide: argon = 5:5:15ml / min) are introduced at 600°C to carry out propane oxidative dehydrogenation reaction, from Fig.11 It can be seen that the initial propane conversion rate, CO2 conversion rate and propylene selectivity of the Pt metal particle confined porous cerium oxide (Pt@CeO2) composite catalytic material (second catalyst) are 35.65%, 33.03% and 92.74%, respectively, proving that the Pt metal particle confined porous cerium oxide (Pt@CeO2) composite catalytic material synthesized with the porous organic framework as a template also has high selectivity and high stability.

[0047] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0048] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for preparing a metal particle confined porous oxide, characterized in that: include: Obtaining metal target; The metal target is placed in an organic solvent, and under ultrasonic conditions, a laser beam is used to bombard the metal target to obtain a colloidal solution containing metal particles; the temperature of the organic solvent is -20 to 0°C; adding aldehyde and amine to the colloidal solution, stirring until the reaction is completed, washing and drying the precipitate to obtain a first powder, wherein the first powder is a metal particle confined porous organic framework; Dispersing the first powder in an ethanol solution of a metal salt, mixing evenly, and concentrating and drying to obtain a second powder; The second powder is calcined to obtain a metal particle confined porous oxide; wherein the calcination temperature is 300-650° C. and the calcination time is 4-7 hours.

2. The method for preparing the metal particle confined porous oxide according to claim 1, characterized in that: The content of metal particles in the colloidal solution is 0.0001-0.0015 g / ml; The laser beam is a nanosecond pulse laser beam, and the laser flux of the nanosecond pulse laser beam is 600-2000mJpulse - 1 cm -1 , the bombardment time of the metal target is 2 to 15 minutes.

3. The method for preparing the metal particle confined porous oxide according to claim 2, characterized in that: The metal includes one or any two of platinum, silver, palladium, gold, gallium, cobalt, nickel, copper, iron, zinc and tin.

4. The method for preparing the metal particle confined porous oxide according to claim 3, characterized in that: The organic solvent includes n-butanol, methanol, ethanol, dimethyl sulfoxide, dioxane, N,N-dimethylformamide and N,N-dimethylacetamide.

5. The method for preparing the metal particle confined porous oxide according to claim 4, characterized in that: The aldehydes include terephthalaldehyde, substituted terephthalaldehyde, isophthalaldehyde, biphenyldicarboxaldehyde, substituted biphenyldicarboxaldehyde, terphenyldicarboxaldehyde, substituted terphenyldicarboxaldehyde and trialdehyde phloroglucinol; and / or, The amines include p-phenylenediamine, substituted p-phenylenediamine, benzylenediamine, substituted benzylenediamine, terphenylenediamine, substituted terphenylenediamine and 1,3,5-triaminobenzene.

6. The method for preparing the metal particle confined porous oxide according to claim 5, characterized in that: The step of adding aldehyde and amine to the colloidal solution comprises: 0.01 mol of aldehyde and 0.01 mol of amine were added to every 200 ml of the colloidal solution.

7. The method for preparing the metal particle confined porous oxide according to claim 6, characterized in that: In the process of adding aldehyde and amine into the colloidal solution and stirring until the reaction is completed, the reaction temperature is 60-80° C. and the reaction time is 12-72 hours.

8. The method for preparing the metal particle confined porous oxide according to claim 7, characterized in that: The metal salts include aluminum nitrate, aluminum chloride, cerium nitrate, cerium ammonium nitrate, cerium chloride, zirconium nitrate and zirconium acetate; and / or, In the ethanol solution of the metal salt, the mass ratio of the metal salt to ethanol is 1:(35-50).

9. A metal particle confined porous oxide, characterized in that: The metal particle confined porous oxide is prepared by the preparation method of any one of claims 1 to 8.

10. Use of the metal particle confined porous oxide according to claim 9 in the dehydrogenation of propane to produce propylene.

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