CN116174011A - Metal nanoparticle and molecular sieve composite catalytic material and preparation method and application thereof - Google Patents

Abstract

The present disclosure relates to a metal nanoparticle and molecular sieve composite catalytic material, a preparation method and application thereof, wherein the composite catalytic material comprises an all-silicon molecular sieve and metal elements M dispersed in crystals of the all-silicon molecular sieve; the metal element M is a metal element capable of forming an oxide aggregate; the composite catalytic material has the following XPS characteristics: 2p of the metal element M to be in the composite catalytic material _3/2 The binding energy of the electrons is denoted as T ₁ 2p of the metal element M to be in the oxide aggregate _3/2 The binding energy of the electrons is denoted as T ₂ T as defined by the following formula (1) ₀ Is any value between 0.5 and 1.0 eV; t (T) ₀ ＝T ₁ ‑T ₂ Formula (1).

Description

Metal nanoparticle and molecular sieve composite catalytic material and preparation method and application thereof

Technical Field

The present disclosure relates to the field of catalytic materials, and in particular, to a metal nanoparticle and molecular sieve composite catalytic material, and preparation and application thereof.

Background

The molecular sieve has the advantages of high specific surface area, high thermal stability, high mechanical stability and the like, and is a good carrier of the metal catalyst. In addition, the regular micropores and mesoporous structures of the molecular sieve can play a role in shape selection (screening of reactants, reaction intermediates and products) in the reaction, and can play a role in synergy or continuous catalysis with the catalysis of the metal active center.

However, for metal catalysts, metal particles having higher surface energy and surface tension are easily sintered by Ostwald ripening or migration-agglomeration processes in a high temperature or hydrothermal environment, resulting in an increase in particle size and a decrease in catalytic activity. In theory, there are two main strategies to improve the sintering resistance of metal particles: (1) Enhancing the interaction between the nanoparticle and the support, e.g., the metal nanoparticle is susceptible to interaction with some of the reducing oxide support (e.g., tiO ₂ 、CeO ₂ Etc.), the strong metal-carrier interactions (SMSI) formed are activated under certain conditions. At this time, obvious electronic offset exists between the general metal and the carrier, and the carrier can cover up the surface of the metal particles through wrapping, modifying or migrating, so that a strong stabilizing and binding effect is generated on the metal, and the sintering resistance of the metal is obviously enhanced. (2) Embedding metal nano particles into weak metal-carrier interaction media such as oxides, mesoporous materials or molecular sieves,the thermal migration path of the metal particles is blocked by confinement.

In general, it is difficult to highly disperse metals into molecular sieve crystals by conventional impregnation methods because the molecular sieve has small micro-pore size, and impregnation methods generally use metal salt solutions for impregnation, and the metal hydrated ions have a size generally larger than the molecular sieve pore size, cannot diffuse into pores, and can only gather on the outer surface of molecular sieve particles. For this study, two series of preparation methods, direct synthesis and post synthesis, were developed.

Direct synthesis generally refers to the direct introduction of a metal precursor during crystallization of a molecular sieve, and the interaction of the metal precursor with the molecular sieve secondary structure can be generated by electrostatic interaction or van der Waals force during hydrothermal crystallization, so that metal nanoparticles are uniformly embedded into the molecular sieve framework during self-assembly of the secondary structural unit. Since the above process is performed under strongly alkaline and high temperature hydrothermal conditions, the metal precursor is extremely prone to form hydroxide precipitates. To solve this problem, precursor metal ions often form complexes with ligands containing lone pair electrons (e.g., organic amine ligands or ammonia, etc.), such as Wang, etc., using ethylenediamine ligands with PdCl ₂ Formation of [ Pd (NH) ₂ CH ₂ CH ₂ NH ₂ )]Cl ₂ The complex precursor is directly synthesized into the silicalite-1 molecular sieve (Pd@silicalite-1) embedding and dispersing uniformly Pd nano particles by a hydrothermal crystallization method.

The microporous molecular sieve can only be diffused by reactants with small molecular size due to the limitation of pore channels, so that the reaction participated by a macromolecular substrate cannot be catalyzed. In order to overcome the defect, mesoporous and even macroporous molecular sieves are introduced into the microporous molecular sieves to form molecular sieves with multi-level pore diameters, so that the performance of the microporous molecular sieves when the microporous molecular sieves are applied to macromolecular reactants is improved. According to different synthesis methods, the synthesis method of the hierarchical pore molecular sieve mainly comprises a skeleton atom removal method, a double-template agent synthesis method ordered micro-mesoporous composite molecular sieve, a hard template agent method, a dry gel conversion method and a silanization method. Among them, the silylation method is relatively simple and one method is applied more.

However, it is still difficult to achieve the two purposes of "complexing a metal precursor with an organic ligand and then introducing the complexed metal precursor into a molecular sieve to perform hydrothermal crystallization to disperse nano particles within the molecular sieve at Cheng Laigao degrees" and "preparing a multi-stage pore molecular sieve by using a silanization method" at present at the same time, so as to obtain a molecular sieve with the advantages of the two, namely, the multi-stage pore molecular sieve capable of directly preparing highly dispersed metal cannot be obtained.

Disclosure of Invention

The purpose of the present disclosure is to provide a metal nanoparticle and molecular sieve composite catalytic material, and a preparation method and application thereof, wherein the composite material has a large specific surface area, a large pore volume and a large molecular substrate reaction activity; the metal nano particles have uniform particle size and are uniformly dispersed in the molecular sieve pore channels.

To achieve the above object, a first aspect of the present disclosure provides a metal nanoparticle and molecular sieve composite catalytic material, including an all-silicon molecular sieve and a metal element M dispersed in crystals of the all-silicon molecular sieve; the metal element M is a metal element capable of forming an oxide aggregate; the composite catalytic material has the following XPS characteristics: the electron binding energy of the metal element M in the composite catalytic material is denoted as T ₁ The electron binding energy of the metal element M in the oxide aggregate is denoted as T ₂ T as defined by the following formula (1) ₀ Is any value between 0.5 and 1.0 eV; t (T) ₀ ＝T ₁ -T ₂ Formula (1).

Optionally, said T ₀ The value of (2) is any value between 0.55 and 0.85 eV.

Optionally, the all-silicon molecular sieve in the composite catalytic material is at least one of an MFI structure molecular sieve, an MEL structure molecular sieve, a BEA structure molecular sieve, an MWW structure molecular sieve, a two-dimensional hexagonal structure molecular sieve, an MOR structure molecular sieve and a TUN structure molecular sieve; preferably one or more selected from MFI structure molecular sieve, MEL structure molecular sieve, BEA structure molecular sieve, MCM structure molecular sieve and SBA structure molecular sieve; further preferably one or more of MFI structure molecular sieve, MEL structure molecular sieve and BEA structure molecular sieve;

the metal M is selected from one or more of manganese, iron, cobalt, nickel, palladium, platinum, copper and gold.

Optionally, the metal M is Co, and the oxide aggregate is Co ₃ O ₄ An aggregate;

the metal M is Mn, and the oxide aggregate is MnO ₂ An aggregate;

the metal M is Fe, and the oxide aggregate is Fe ₂ O ₃ An aggregate;

the metal M is Ni, and the oxide aggregate is NiO aggregate;

the metal M is Pd, and the oxide aggregate is a PdO aggregate;

The metal M is Pt, and the oxide aggregate is PtO ₂ An aggregate; or alternatively

The metal M is Cu, and the oxide aggregate is a CuO aggregate;

preferably, when the metal element M is Co, mn, fe, ni or Cu, the electron binding energy of the metal element M is 2p of the metal element M _3/2 Binding energy of electrons; when the metal element M is Pt, the electron binding energy of the metal element M is 4f of the metal element M _7/2 Binding energy of electrons; when the metal element M is Pd, the electron binding energy of the metal element M is 3d of the metal element M _5/2 Binding energy of electrons.

Optionally, in the composite catalytic material, the molar ratio of the metal M element to the silicon element is (0.001-0.2): 1, preferably (0.001 to 0.15): 1.

optionally, the BET specific surface area of the composite catalytic material is 400-800 m ² And/g, wherein the total pore volume is 0.3-0.65 mL/g, the micropore volume is 0.1-0.19 mL/g, the mesopore volume is 0.15-0.46 mL/g, the metal element M in the composite catalytic material exists in the form of metal nano particles, and the average particle size of the metal nano particles is 0.5-10 nm.

A second aspect of the present disclosure provides a method of preparing a metal nanoparticle and molecular sieve composite catalytic material, comprising the steps of:

S1, mixing a template agent, a silicon source, water, a metal M precursor, a silanization reagent and a structural filler to obtain a reaction mixture, wherein the structural filler is an amphiphilic surfactant and/or a hard template agent; s2, carrying out hydrothermal crystallization treatment and roasting treatment on the reaction mixture.

Optionally, in step S1, the silicon source: template agent: water: metal M element: the molar ratio of the silylating agent is 1: (0.001-1): (5-100): (0.001-0.2): (0.025-0.4); preferably 1: (0.005-0.5): (5-100): (0.001-0.15): (0.025-0.3); siO in the reaction mixture ₂ The weight ratio of the structural filler to the structural filler is (3-100): 1.

optionally, step S1 includes:

a. mixing a template agent, a silicon source and water to obtain a silicon hydrolysis solution;

b. mixing a metal M precursor and the silicon hydrolysis solution to obtain a first mixed material;

c. respectively adding a silylation reagent and a structural filler into the first mixed material, and mixing to obtain a reaction mixture; preferably, the conditions of mixing in step c include: stirring at 20-80 deg.c for 0.5-2 hr.

Optionally, the silicon source is selected from at least one of silicone grease, solid silica gel, white carbon black and silica sol; preferably at least one selected from the group consisting of silicone grease, solid silica gel and white carbon black;

Further preferred is a silicone grease having a structure represented by the following formula (A):

wherein R is _a 、R _b 、R _c 、R _d Each independently selected from alkyl groups having 1 to 6 carbon atoms, said alkyl groups being branched or straight chain alkyl groups; preferably, R _a 、R _b 、R _c 、R _d Each independently selected from a straight chain alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 to 4 carbon atoms; further preferably, the R _a 、R _b 、R _c 、R _d Each independently of the otherSelected from methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl; further preferably, the organic silicone grease is selected from one or more of tetramethyl silicate, tetraethyl silicate, tetrabutyl silicate and dimethyl diethyl silicone grease.

Optionally, in step S1, the template agent is an organic base, preferably at least one selected from quaternary ammonium base, aliphatic amine and aliphatic alcohol amine; further preferably, the template is at least one selected from structural quaternary ammonium bases represented by the following formula (B):

R ₁ 、R ₂ 、R ₃ and R is ₄ Each selected from alkyl groups having 1 to 4 carbon atoms, preferably straight chain alkyl groups having 1 to 4 carbon atoms and branched alkyl groups having 3 to 4 carbon atoms, more preferably R ₁ 、R ₂ 、R ₃ And R is ₄ At least one selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl and tert-butyl;

Further preferably, the all-silicon molecular sieve is an MFI type molecular sieve, and the template agent is tetrapropylammonium hydroxide or a mixture of tetrapropylammonium hydroxide and one or more selected from tetrapropylammonium chloride and tetrapropylammonium bromide; or the all-silicon molecular sieve is a MEL molecular sieve, and the template agent is tetrabutylammonium hydroxide or a mixture of tetrabutylammonium hydroxide and one or more selected from tetrabutylammonium chloride and tetrabutylammonium bromide; or the molecular sieve is Beta-type molecular sieve, and the template agent is tetraethylammonium hydroxide or a mixture of tetraethylammonium hydroxide and one or more selected from tetraethylammonium chloride and tetraethylammonium bromide.

Optionally, in the step a, the silicon source is organic silicone grease, and the step a further comprises hydrolysis alcohol removal treatment after the template agent, the organic silicone grease and water are mixed to obtain a hydrolysis solution of the silicon;

the conditions for the hydrolysis alcohol expelling treatment comprise: stirring and hydrolyzing for 2-10 hours at 0-95 ℃; preferably at 50-95 deg.C for 2-8 hr.

Optionally, in step S1, the metal M precursor is one or more of an inorganic metal compound and an organic metal compound; the inorganic metal compound is water-soluble inorganic salt of metal M; the water-soluble inorganic salt of the metal M is selected from one or more of chloride, hydrated chloride, sulfate, hydrated sulfate and nitrate of the metal M; the organic metal compound is an organic ligand compound of metal M; preferably, the metal M precursor is a water-soluble inorganic salt of metal M;

The metal M is selected from one or more of manganese, iron, cobalt, nickel, palladium, platinum, copper and gold;

preferably, the metal M precursor is in the form of an aqueous solution of the metal M precursor, and the molar ratio of the metal M element to water in the aqueous solution of the metal M precursor is 1: (50-500).

Optionally, in step S1, the silylating agent has the general formula R ₅ Si(R ₆ )(R ₇ )R ₈ Wherein R is ₅ 、R ₆ 、R ₇ 、R ₈ Each independently is halogen, alkyl, alkoxy, aryl, mercapto or amino, and R ₅ 、R ₆ 、R ₇ 、R ₈ At least one of which is alkyl, alkoxy, aryl, mercapto or amino; the carbon atoms of the alkyl, alkoxy, mercapto and amino are each independently 1-18, and the carbon atoms of the aryl are 6-18;

preferably, the silylating agent is selected from one or more of dimethyldichlorosilane, N-phenyl-3-aminopropyl trimethoxysilane, phenyl trimethoxysilane, 1, 7-dichlorooctanethyltetrasiloxane, hexadecyl trimethoxysilane, octyl triethoxysilane, 3-aminopropyl trimethoxysilane, N-beta- (aminoethyl) -gamma-aminopropyl trimethoxysilane and 3-mercaptopropyl trimethoxysilane; further preferably one or more selected from the group consisting of N-phenyl-3-aminopropyl trimethoxysilane, N-beta- (aminoethyl) -gamma-aminopropyl trimethoxysilane and 3-mercaptopropyl trimethoxysilane.

Optionally, in step S1, the structural filler is selected from one or more of cetyltrimethylammonium bromide, sodium dodecylbenzenesulfonate, PEO-PPO-PEO triblock copolymer, mesoporous carbon and natural cellulose.

Optionally, in step S2, the conditions of the hydrothermal crystallization treatment include: the hydrothermal crystallization time is 0.5-10 days, and the hydrothermal crystallization temperature is 110-200 ℃; preferably, the hydrothermal crystallization time is 0.5-5 days, and the hydrothermal crystallization temperature is 150-200 ℃; the pressure is autogenous pressure;

the conditions of the calcination treatment include: roasting temperature is 400-900 ℃ and roasting time is 1-16 hours; preferably, the roasting temperature is 400-800 ℃ and the roasting time is 2-8 hours.

A third aspect of the present disclosure provides a metal nanoparticle and molecular sieve composite catalytic material prepared according to the method of the second aspect of the present disclosure.

A fourth aspect of the present disclosure provides the use of the metal nanoparticle and molecular sieve composite catalytic material of the first or third aspect of the present disclosure in catalyzing a co-oxidation reaction of a macromolecular aldehyde/olefin; preferably in catalyzing the co-oxidation of cyclooctene and isobutyraldehyde.

Through the technical scheme, the metal nano particle and molecular sieve composite catalytic material, the preparation method and the application thereof are provided, and the metal nano particle and molecular sieve composite material is prepared by simultaneously adding a metal precursor, a silanization reagent and a macromolecular structure filler into a crystallization system, wherein the molecular sieve of the prepared composite material has large specific surface area, pore volume and macromolecular substrate reaction activity; the metal nano particles have uniform particle size and are uniformly dispersed in mesoporous pore canals of the hierarchical pore molecular sieve; the XPS binding energy of the metal M element in the composite material is 0.5-1.0 eV higher than that of the metal M element in the oxide aggregate of the metal M, and the composite material has higher catalytic activity in the co-oxidation reaction of cyclooctene and isobutyraldehyde.

Additional features and advantages of the present disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification, illustrate the disclosure and together with the description serve to explain, but do not limit the disclosure. In the drawings:

FIG. 1 is an SEM spectrum of the product prepared according to example 1 of the disclosure.

Fig. 2 is an XRD spectrum of the product prepared in example 1 of the present disclosure.

Fig. 3 is a TEM spectrum of the product prepared in example 1 of the present disclosure.

FIG. 4 is an infrared (FT-IR) spectrum of the product prepared in example 1 of the present disclosure.

FIG. 5 is a graph of diffuse ultraviolet-visible (UV-Vis) reflectance of a product prepared in example 1 of the present disclosure.

FIG. 6 is an EDX spectrum of the product obtained in example 1.

Figure 7 is an XRD pattern for the product obtained in example 10.

FIG. 8 is an XRD spectrum of the product obtained in example 11.

Fig. 9 is a Co XPS spectrum of the metal element of the product obtained in example 1.

Detailed Description

Specific embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating and illustrating the disclosure, are not intended to limit the disclosure.

The inventors of the present disclosure surprisingly found in experiments that, by introducing a metal precursor during the synthesis of a molecular sieve, and then continuously introducing a silylating agent and a structural filler, the obtained mixture is subjected to hydrothermal crystallization, washing and roasting, and the obtained composite catalytic material comprising all-silicon molecular sieve and metal M-oxide nanoparticles has a large specific surface area and pore volume, the metal oxide nanoparticles have uniform particle size and are uniformly dispersed in the pores of the molecular sieve, and when T is contained in the composite material ₀ (i.e.T ₁ -T ₂ ) Has a value of 0.5eV or more (T ₁ Representing the metals in the composite catalytic materialXPS binding energy of M element, T ₂ Representing the XPS binding energy of the metal M element in the oxide aggregate of the metal M), the composite material has good catalytic activity in the co-oxidation reaction of macromolecular aldehyde/olefin, for example, when the composite material is used for the co-oxidation reaction of cyclooctene and isobutyraldehyde, higher cyclooctene conversion rate and cyclooctene epoxide selectivity can be obtained.

A first aspect of the present disclosure provides a metal oxide nanoparticle and molecular sieve composite catalytic material comprising an all-silicon molecular sieve and a metal element M dispersed within crystals of the all-silicon molecular sieve; the metal element M is a metal element capable of forming an oxide aggregate;

The composite catalytic material has the following XPS characteristics:

the electron binding energy of the metal element M in the composite catalytic material is denoted as T ₁ ，

The electron binding energy of the metal element M in the oxide aggregate is denoted as T ₂ T as defined by the following formula (1) ₀ Is any value between 0.5 and 1.0 eV;

T ₀ ＝T ₁ -T ₂ formula (1).

The present disclosure provides a metal oxide nanoparticle and molecular sieve composite catalytic material, the molecular sieve of the composite material having a large specific surface area, pore volume and macromolecular substrate reactivity; the metal oxide nano particles have uniform particle size and are uniformly dispersed in mesoporous pore channels of the hierarchical pore molecular sieve; the XPS binding energy of the metal M element in the composite material is 0.5-1.0 eV higher than that of the metal M element in the oxide aggregate of the metal M, and the composite material has higher catalytic activity in the co-oxidation reaction of cyclooctene and isobutyraldehyde.

In the present disclosure, metal M oxide aggregates refer to the species of conventional oxides obtained after calcination treatment of metal M precursors (e.g., nitrates, chlorides, etc.) known in the art during molecular sieve synthesis, e.g., metal cobalt oxide aggregates are Co ₃ O ₄ The aggregate of the oxide of the metal Cu is CuO.

In a preferred embodiment, theT of (2) ₀ The value of (2) is any value between 0.55 and 0.85eV, and the T of the composite catalytic material ₀ Within this range, there is higher catalytic activity, and higher cyclooctene conversion and cyclooctene epoxide selectivity.

In one embodiment, the all-silicon molecular sieve in the composite catalytic material is at least one of an MFI structure molecular sieve, an MEL structure molecular sieve, a BEA structure molecular sieve, an MWW structure molecular sieve, a two-dimensional hexagonal structure molecular sieve, an MOR structure molecular sieve and a TUN structure molecular sieve; preferably one or more selected from MFI structure molecular sieve, MEL structure molecular sieve, BEA structure molecular sieve, MCM structure molecular sieve and SBA structure molecular sieve; further preferably one or more of MFI structure molecular sieve, MEL structure molecular sieve and BEA structure molecular sieve;

the metal M is selected from one or more of manganese, iron, cobalt, nickel, palladium, platinum, copper and gold; preferably one or more selected from manganese, iron, cobalt, nickel, palladium, platinum and copper.

In an alternative embodiment, the metal M is Co and the oxide aggregate is Co ₃ O ₄ An aggregate;

in an alternative embodiment, the metal M is Mn and the oxide aggregate is MnO ₂ An aggregate;

in an alternative embodiment, the metal M is Fe and the oxide aggregate is Fe ₂ O ₃ An aggregate;

in an alternative embodiment, the metal M is Ni and the oxide aggregate is NiO aggregate;

in an alternative embodiment, the metal M is Pd and the oxide aggregates are PdO aggregates;

in an alternative embodiment, the metal M is Pt and the oxide aggregate is PtO ₂ An aggregate;

in an alternative embodiment, the metal M is Cu and the oxide aggregate is a CuO aggregate;

preferably, when the metal element M is Co, mn, fe, ni or Cu, the electrons of the metal element M2p with binding energy of metal element M _3/2 Binding energy of electrons; when the metal element M is Pt, the electron binding energy of the metal element M is 4f of the metal element M _7/2 Binding energy of electrons; when the metal element M is Pd, the electron binding energy of the metal element M is 3d of the metal element M _5/2 Binding energy of electrons.

In one embodiment, in the composite catalytic material, the molar ratio of the metal M element to the silicon element is (0.001 to 0.2): 1, preferably (0.001 to 0.15): 1.

in one embodiment, the metal element M in the composite catalytic material is present in the form of metal nanoparticles having an average particle diameter of 0.5 to 10nm, preferably 0.5 to 5nm; BET specific surface area of 400-800 m ² Preferably 400 to 700m ² /g; the total pore volume is 0.3-0.65 mL/g, preferably 0.31-0.63 mL/g; the micropore volume is 0.1-0.19 mL/g, preferably 0.11-0.18 mL/g; the mesoporous volume is 0.15-0.46 mL/g, preferably 0.17-0.46 mL/g. The composite catalytic material also has a multi-stage pore structure, is favorable for catalyzing reaction substrates with different sizes, and is particularly suitable for catalyzing macromolecular substrate reactions.

A second aspect of the present disclosure provides a method of preparing a metal nanoparticle and molecular sieve composite catalytic material, comprising the steps of:

s1, mixing a template agent, a silicon source, water, a metal M precursor, a silanization reagent and a structural filler to obtain a reaction mixture, wherein the structural filler is an amphiphilic surfactant and/or a hard template agent;

s2, carrying out hydrothermal crystallization treatment and roasting treatment on the reaction mixture.

The metal precursor, the silanization reagent and the macromolecular structure filler are introduced into the molecular sieve synthesis raw material, so that the hole expanding effect of the highly dispersed metal oxide nano particles and the molecular sieve support layer can be considered, and the multistage pore molecular sieve composite catalytic material of the highly dispersed metal oxide nano particles can be prepared.

In the method, metal ions and a silanization reagent form a complex, and metal oxide nano particles in a pore canal of a molecular sieve obtained after hydrothermal crystallization and roasting have high dispersity; and the silicon hydroxyl of the silanization reagent and the silicon hydroxyl of the organic silicon source are hydrolyzed and condensed to generate stable Si-O-Si bond, thereby ensuring the realization of the hole expanding effect of the support layer. In addition, the long carbon chain of the silylation agent and the structural filler of the amphiphilic surfactant can form a stable and controllable structural unit (the long carbon chain of the silylation agent and the hydrophobic group of the surfactant are close to each other and interact with van der Waals force), so that fine adjustment effect on expanding the support layer is achieved; or the space filling function is realized by using a hard template agent with controllable size. The molecular sieve of the finally obtained composite catalytic material generates a mesoporous structure with ordered and controllable pore diameter (controlled by the chain length of the alkyl chain of the silylating agent). And metal M oxide nano particles formed by metal M introduced in the molecular sieve synthesis process can be uniformly dispersed in mesoporous pore channels of the hierarchical pore molecular sieve.

In one embodiment, in step S1, the silicon source: template agent: water: metal M element: the molar ratio of the silylating agent is 1: (0.001-1): (5-100): (0.001-0.2): (0.025-0.4); preferably 1: (0.005-0.5): (5-100): (0.001-0.15): (0.025-0.3); siO in the reaction mixture ₂ The weight ratio of the structural filler to the structural filler is (3-100): 1. specifically, the water used in step S1 may be water commonly used in synthesizing molecular sieves, and deionized water is preferred in order to avoid the introduction of heteroatoms.

In a preferred embodiment, step S1 comprises:

a. mixing a template agent, a silicon source and water to obtain a silicon hydrolysis solution;

b. mixing a metal M precursor and the silicon hydrolysis solution to obtain a first mixed material;

c. respectively adding a silylation reagent and a structural filler into the first mixed material, and mixing to obtain a reaction mixture; preferably, the conditions of mixing in step c include: stirring at 20-80 deg.c for 0.5-2 hr.

In one embodiment, in step S1, the silicon source is at least one selected from the group consisting of silicone grease, solid silica gel, white carbon black, and silica sol; preferably at least one selected from the group consisting of silicone grease, solid silica gel and white carbon black; the general formula of the silicone grease is a structure shown in the following formula (A):

wherein R is _a 、R _b 、R _c 、R _d Each independently selected from alkyl groups having 1 to 6 carbon atoms, said alkyl groups being branched or straight chain alkyl groups; preferably, R _a 、R _b 、R _c 、R _d Each independently selected from a straight chain alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 to 4 carbon atoms. For example R _a 、R _b 、R _c 、R _d Each independently is methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl. Further preferably R _a 、R _b 、R _c 、R _d Each independently is methyl or ethyl.

In a preferred embodiment, the silicone grease is selected from one or more of tetramethyl silicate, tetraethyl silicate, tetrabutyl silicate and dimethyl diethyl silicone grease.

According to the present disclosure, in step S1, the template agent is an organic base, preferably at least one selected from the group consisting of quaternary ammonium bases, aliphatic amines, and aliphatic alcohol amines. Wherein, the quaternary ammonium base can be organic quaternary ammonium base; the aliphatic amine may be NH ₃ A compound formed by substituting at least one hydrogen of the compound with an aliphatic hydrocarbon group (e.g., an alkyl group); the aliphatic alcohol amine can be various NH ₃ A compound in which at least one hydrogen is substituted with an aliphatic group having a hydroxyl group (e.g., an alkyl group).

Further preferably, the template is at least one selected from structural quaternary ammonium bases represented by the following formula (B):

R ₁ 、R ₂ 、R ₃ and R is ₄ Each selected from alkyl groups having 1 to 4 carbon atoms, preferably straight chain alkyl groups having 1 to 4 carbon atoms and branched alkyl groups having 3 to 4 carbon atoms, further preferably R ₁ 、R ₂ 、R ₃ And R is ₄ Each is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl. A step of

The template is preferably at least one of tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide (including various isomers of tetrapropylammonium hydroxide, such as tetra-n-propylammonium hydroxide and tetraisopropylammonium hydroxide), and tetrabutylammonium hydroxide (including various isomers of tetrabutylammonium hydroxide, such as tetra-n-butylammonium hydroxide and tetraisobutylammonium hydroxide).

In a preferred embodiment, the all-silicon molecular sieve is an MFI-type molecular sieve, and the template agent is tetrapropylammonium hydroxide or a mixture of tetrapropylammonium hydroxide and one or more selected from tetrapropylammonium chloride and tetrapropylammonium bromide; or in another preferred embodiment, the all-silicon molecular sieve is MEL type molecular sieve, and the template agent is tetrabutylammonium hydroxide or a mixture of tetrabutylammonium hydroxide and one or more selected from tetrabutylammonium chloride and tetrabutylammonium bromide; alternatively, in another preferred embodiment, the molecular sieve is a Beta-type molecular sieve, and the template agent is tetraethylammonium hydroxide or a mixture of tetraethylammonium hydroxide and one or more selected from tetraethylammonium chloride and tetraethylammonium bromide. The molecular sieve with different structures can be prepared by selecting different templates.

In one embodiment, the silicon source is organic silicone grease, and the method further comprises hydrolysis alcohol removal treatment after the template agent, the organic silicone grease and water are mixed to obtain a hydrolysis solution of the silicon;

the conditions for the hydrolysis alcohol expelling treatment comprise: stirring and hydrolyzing for 2-10 hours at 0-95 ℃; preferably, the hydrolysis is carried out for 2 to 8 hours under stirring at 50 to 95 ℃;

preferably, the hydrolysis alcohol-expelling treatment is performed so that the mass content of alcohol produced by hydrolysis of the obtained silicone grease in the silicon hydrolysis solution is 10ppm or less.

According to the present disclosure, the metal precursor may have a wide range of types, and any material containing the metal (e.g., a compound containing a metal element and/or a metal simple substance) may achieve the object of the present disclosure.

In one embodiment, in step S1, the metal M precursor is one or more of an inorganic metal compound and an organic metal compound; the organic metal compound is water-soluble inorganic salt of metal M; the water-soluble inorganic salt of the metal M is selected from one or more of chloride, hydrated chloride, sulfate, hydrated sulfate and nitrate of the metal M; the organic metal compound is an organic ligand compound of metal M; preferably, the metal M precursor is a water-soluble inorganic salt of metal M;

The metal M is selected from one or more of manganese, iron, cobalt, nickel, palladium, platinum, copper and gold;

preferably, the metal M precursor is an aqueous solution of metal M precursor, and the molar ratio of metal M element to water in the aqueous solution of metal M precursor is 1: (50-500).

In one embodiment, in step S1, the silylating agent has the general formula R ₅ Si(R ₆ )(R ₇ )R ₈ Wherein R is ₅ 、R ₆ 、R ₇ 、R ₈ Each independently is halogen, alkyl, alkoxy, aryl, mercapto or amino, and R ₅ 、R ₆ 、R ₇ 、R ₈ At least one of which is alkyl, alkoxy, aryl, mercapto or amino; the number of carbon atoms of the alkyl group, the alkoxy group, the mercapto group and the amine group is 1 to 18, preferably 1 to 12; the number of carbon atoms of the aromatic group may be 6 to 18, preferably 6 to 12.

Preferably, the silylating agent is selected from one or more of dimethyldichlorosilane, N-phenyl-3-aminopropyl trimethoxysilane, phenyl trimethoxysilane, 1, 7-dichlorooctanethyltetrasiloxane, hexadecyl trimethoxysilane, octyl triethoxysilane, 3-aminopropyl trimethoxysilane, N-beta- (aminoethyl) -gamma-aminopropyl trimethoxysilane and 3-mercaptopropyl trimethoxysilane; further preferred is at least one of N-phenyl-3-aminopropyl trimethoxysilane, N-beta- (aminoethyl) -gamma-aminopropyl trimethoxysilane and 3-mercaptopropyl trimethoxysilane.

In one embodiment, in step S1, the structural filler is selected from one or more of cetyltrimethylammonium bromide, sodium dodecylbenzenesulfonate, PEO-PPO-PEO triblock copolymer, mesoporous carbon and natural cellulose.

In one embodiment, in step S2, the conditions of the hydrothermal crystallization treatment include: the hydrothermal crystallization time is 0.5-10 days, and the hydrothermal crystallization temperature is 110-200 ℃; preferably, the hydrothermal crystallization time is 0.5-5 days, and the hydrothermal crystallization temperature is 150-200 ℃; the pressure is autogenous pressure.

In one embodiment, in step S2, the conditions of the baking process include: roasting temperature is 400-900 ℃ and roasting time is 1-16 hours; preferably, the roasting temperature is 400-800 ℃ and the roasting time is 2-8 hours.

A third aspect of the present disclosure provides a metal nanoparticle and molecular sieve composite catalytic material prepared according to the method of the second aspect of the present disclosure.

A fourth aspect of the present disclosure provides the use of the metal nanoparticle and molecular sieve composite catalytic material of the first or third aspect of the present disclosure to catalyze the co-oxidation of macromolecular aldehydes/olefins; preferably in catalyzing the co-oxidation of cyclooctene and isobutyraldehyde.

In a specific embodiment, the reaction conditions in the use of catalyzing the co-oxidation of cyclooctene and isobutyraldehyde include: the molar ratio of isobutyraldehyde to cyclooctene is 2-8: 1, taking the total weight of isobutyraldehyde and cyclooctene as a reference, wherein the weight ratio of the metal nano particles to the molecular sieve composite material is 1-20 percent; 0.1-2 MPa, the reaction temperature is 20-120 ℃ and the reaction time is 2-48 hours. Alternatively, the reaction is carried out in a slurry bed reactor.

When the composite catalytic material is used for catalyzing the co-oxidation reaction of cyclooctene and isobutyraldehyde, the conversion rate of cyclooctene is not lower than 75mol percent, the selectivity of the target product cyclooctene is not lower than 85mol percent, and the conversion rate of isobutyraldehyde is not lower than 98mol percent.

The present disclosure will be further illustrated by the following examples.

In the present disclosure, X-ray diffraction (XRD) pattern measurement of a sample was performed on a Siemens D5005 type X-ray diffractometer with a source of kα (Cu) and a test range of 2θ from 0.5 ° to 70 °.

The Fourier infrared (FT-IR) spectrum of the sample is measured on a Nicolet 8210 type Fourier infrared spectrometer, and the measuring range is 400-4000 cm ^-1 。

The solid ultraviolet-visible diffuse reflectance spectrum (UV-vis) of the sample is measured on a SHIMADZU UV-3100 ultraviolet-visible spectrometer with a test range of 400-4000 cm ^-1 。

SEM images of the samples were obtained on a high resolution cold field emission scanning electron microscope in hitachi S4800.

Transmission electron microscopy TEM of the samples was obtained on a Tecnai G2F20S-TWIN transmission electron microscope from FEI company. The average particle diameter of the metal oxide nanoparticles was obtained according to TEM electron microscopy.

XPS characterization of the samples was performed on an ESCALAB 250 type X-ray photoelectron spectrometer, monochromatic AlK alpha X rays, energy 1486.6eV, power 150W, and C1s peak (284.8 eV) of pollution carbon was used to correct nuclear power shift.

The total specific surface area and total pore volume of the samples were measured on a Micromeritics company ASAP245 static nitrogen adsorber according to ASTM D4222-98 standard method. The determination of the adsorption and desorption isotherms for low temperature nitrogen adsorption of the sample was performed according to ASTM D4222-98 standard method.

The cobalt nitrate used in the examples of the present disclosure was cobalt nitrate hexahydrate.

Example 1

(1) 1.6g of an aqueous solution of tetrapropylammonium hydroxide (TPAOH, 0.002 mol) having a concentration of 25.05 wt%, 20.8g of tetraethyl silicate (0.1 mol, siO) ₂ 6 g) and 52.8g of water (3 mol) were added in sequence to a 500mL beaker and placed in a flask with the addition ofUniformly mixing the materials on a magnetic stirrer with the functions of heating and stirring, stirring the materials for 2 hours at 50 ℃, and supplementing evaporated water at fixed time to obtain colorless transparent silica gel solution;

(2) Uniformly stirring 0.03g of cobalt nitrate hexahydrate (0.0001 mol) and 0.18g of water (0.01 mol) to obtain an aqueous cobalt solution, and mixing the aqueous cobalt solution with the silicon hydrolysis solution obtained in the step (1);

(3) To the mixture of step (2) was added 0.64g of N-phenyl-3-aminopropyl trimethoxysilane (PHAPTMS, 0.0025 mol) and 0.3g of PEO-PPO-PEO triblock copolymer (P123, purchased from Inoki, weight average molecular weight 5800) and stirred for 0.5 hours;

(4) Transferring the mixture obtained in the step (3) into a stainless steel closed reaction kettle, crystallizing at the constant temperature of 175 ℃ for 24 hours to obtain a sample, filtering and washing the obtained sample, drying at the temperature of 110 ℃ for 6 hours, and roasting at the temperature of 600 ℃ in a muffle furnace for 6 hours to obtain the metal oxide nanoparticle and molecular sieve composite material product, namely CAT-1.

The BET specific surface area, total pore volume, micropore volume, mesopore volume, and average particle size of the metal nanoparticles contained in the composite catalytic material of CAT-1 are shown in Table 2.

SEM of CAT-1 is shown in FIG. 1; XRD spectrum of CAT-1 is shown in figure 2, and XRD analysis shows that it has MFI structure; a TEM image of CAT-1 is shown in FIG. 3; the infrared spectrum of CAT-1 is shown in FIG. 4; the ultraviolet-visible spectrum of CAT-1 is shown in the figure. From FIGS. 1 and 3, it can be seen that CAT-1 prepared in this example has regular shape and uniform size; 960cm in FIG. 4 ^-1 The characteristic peaks in the vicinity indicate that Co is bonded to the silicon skeleton surface; the characteristic peaks at 450 to 700nm in FIG. 5 illustrate the interaction between Co and Si. The EDX obtained by TEM test of CAT-1 is shown in FIG. 6, and it can be seen that the metal Co is uniformly dispersed in the molecular sieve. XPS spectra of metallic element Co of CAT-1 is shown in FIG. 9.

Comparative example 1

This comparative example was prepared as in example 1, except that no silylating agent and no structural filler were added, and the proportions and synthesis conditions, and the results are shown in Table 1. Other conditions and operations refer to example 1. The product obtained was designated as sample D-1.

Comparative example 2

This comparative example was prepared according to the method disclosed in patent CN 109821568A.

Into the flask, 0.51g of cobalt nitrate hexahydrate, 1.28g of cetyltrimethylammonium bromide and 2.11g of sodium hydroxide were added, followed by addition of 65ml of deionized water, heating in a 40℃water bath and stirring at 400 rpm for 2 hours. Ethyl orthosilicate was added dropwise to the above solution at a rate of 4 seconds per drop, the final molar ratio of metallic cobalt to silicon source was 0.08, and stirring was continued at 400 revolutions per minute for 24 hours. The silicate hydrosol containing the metal nitrate is moved into a reaction kettle, and the volume of the silicate hydrosol accounts for about 70 percent of the kettle. The silicate hydrosol is put into a reaction kettle for hydrothermal crystallization at 120 ℃ for 24 hours. And adding the product obtained in the reaction kettle into deionized water with the volume of 30 times, washing for 3 times, centrifuging to be neutral, and drying the obtained product at 100 ℃ for 12 hours. Roasting at 550 ℃ for 300min at a temperature rising rate of 1 degree/min to 550 ℃, and obtaining the product which is marked as D-2.

Comparative example 3

This comparative example was prepared according to the method of Ning Wang et al (JACS, 2016, vol.138 pages 7484-7487).

Deionized water was mixed with 13g of TPAOH solution and stirred continuously for 10 minutes, followed by the addition of 8.32g of ethyl orthosilicate (0.04 mol). After stirring continuously for 6 hours, the mixture became clear after complete hydrolysis. Preparation of [ Pd (NH) by dissolving 0.052g of cobalt nitrate hexahydrate (0.18 mmol, molar ratio of metallic cobalt to silicon source 0.0045) in a mixture of 0.3mL of ethylenediamine and 3mL of water ₂ CH ₂ CH ₂ NH ₂ ) ₂ ]Cl ₂ The solution was then added dropwise to the above mixture, and stirring was carried out for 30 minutes without precipitation occurring. The reaction mixture was transferred to a 100mL stainless steel autoclave lined with polytetrafluoroethylene and subjected to static crystallization in a conventional oven at 170 ℃ for 4 days. The solid product obtained was centrifuged, washed several times with water and ethanol, oven-dried overnight at 80 ℃, calcined in an air atmosphere at 550 ℃ for 8 hours, and finally reduced with hydrogen to give the product, designated D-3.

Examples 2 to 9

The corresponding products CAT-2 to CAT-9 were prepared in the same manner as in example 1, the proportions and synthesis conditions and the results are shown in Table 1. Other conditions and operations refer to example 1. SEM images of CAT-2 to CAT-9 are similar to those of FIG. 1 and XRD images are similar to those of FIG. 2, and XRD analysis shows that the catalyst has an MFI structure; the TEM image is similar to that of fig. 3; the FT-IR spectrum is similar to that of FIG. 4; the UV-Vis spectrum is similar to that of FIG. 5.

Example 10

The cobalt-containing hierarchical pore beta molecular sieve was prepared by changing the ratio and the template agent according to the method of example 1, wherein the template agent is tetraethylammonium hydroxide (TEAOH), the ratio and the synthesis conditions and the results are shown in Table 1, and the obtained product is CAT-10. The XRD spectrum of the obtained product is shown in figure 7, and shows that the product has a beta molecular sieve structure.

Example 11

Cobalt-containing hierarchical pore MEL molecular sieves were prepared in practice, the ratio and the template were changed by the method of example 1, the template used was tetrabutylammonium hydroxide (TBAOH), the ratio and synthesis conditions and the results are shown in Table 1, and the obtained product was designated CAT-11. The XRD spectrum of the obtained product is shown in figure 8, and shows that the product has MEL molecular sieve structure.

Example 12

The cobalt-containing hierarchical pore MFI molecular sieve was prepared by the method of reference example 1, and the proportions, synthesis conditions and results are shown in Table 1. The resulting product was designated CAT-12. Wherein the hydrothermal crystallization temperature is 140 ℃ and the hydrothermal crystallization time is 7 days; the roasting temperature is 840 ℃ and the roasting time is 9 hours.

The BET specific surface areas, total pore volumes, micropore volumes, mesopore volumes, and average particle diameters of metal nanoparticles contained in the composite materials of the products obtained in the above examples and comparative examples are listed in table 2 below.

TABLE 1

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In table 1, TPAOH is tetrapropylammonium hydroxide, TPABr is tetrapropylammonium bromide, TBAOH is tetrabutylammonium hydroxide, TEAOH is tetraethylammonium hydroxide; PHAPTMS is N-phenyl-3-aminopropyl trimethoxy silane, APTES is 3-aminopropyl triethoxy silane, KH792 is silane coupling agent KH792 (diamino functional silane); p123 is PEO-PPO-PEO triblock copolymer, CTAB is cetyl trimethyl ammonium bromide, SDBS is sodium dodecyl benzene sulfonate. Reagents employed in the present disclosure may be obtained through conventional purchase channels.

TABLE 2

Wherein the pores with the diameter smaller than 2nm are micropore diameters; the pores with the diameter of 2-50 nm are mesoporous.

As can be seen from Table 2, compared with D-1 prepared in comparative example 1 (without addition of silylating agent and structural filler) and D-3 prepared in comparative example 3 (without addition of silylating agent and structural filler), examples 1-12 of the present disclosure added silylating agent and structural filler during the preparation process, and the resulting products CAT-1-CAT-12 had higher mesoporous volume, demonstrating that the method provided by the present disclosure is capable of effectively reaming molecular sieves.

Test case

This test example illustrates the reaction effect of the examples provided in this disclosure and the samples prepared in the comparative examples for the co-oxidation of cyclooctene and isobutyraldehyde.

The reagents used in this test example were all commercially available chemically pure reagents, and the concentrations of the respective substances after the reaction were quantitatively analyzed by gas chromatography. 6890 type gas chromatograph manufactured by Agilent company is used; the analytical chromatographic column used was an HP-5 column.

The conversion of cyclooctene, isobutyraldehyde conversion, and cyclooctene selectivity of the examples were calculated according to the following formulas (2) - (4), respectively:

the samples prepared in the above comparative examples and examples were taken, respectively, according to isobutyraldehyde: cyclooctene = 3:1 in a slurry bed, wherein a slurry bed closed system is connected with a normal pressure pure oxygen balloon as an oxygen source, the oxygen pressure is 0.1MPa, the cyclooctene dosage is 1mmol, the catalyst dosage is 50mg, and the solvent acetonitrile dosage is 2.5mL. The reaction was stable at 25℃for 6 hours, and the results of the sample analysis are shown in Table 3.

TABLE 3 Table 3

Wherein, cobalt oxide aggregate Co ₃ O ₄ T of (2) ₂ T of NiO, an oxide aggregate of nickel, with a value of 781.25eV ₂ Oxide aggregate MnO of manganese with value 854.80eV ₂ T of (2) ₂ T of copper oxide aggregate CuO with value 642.10eV ₂ Iron oxide aggregate Fe with a value of 933.60eV ₂ O ₃ T of (2) ₂ The value was 710.80eV.

As can be seen from the data in Table 3, the metal oxide nanoparticles prepared in the examples of the present disclosure and molecular sieve composite catalytic materials CAT-1 to CAT-12 have T compared with D-1 to D-3 prepared in the comparative example ₀ Between 0.5 and 1.0eV, the catalyst has higher catalytic activity in the co-oxidation reaction of cyclooctene and isobutyraldehyde, and the conversion rate of cyclooctene and the selectivity of cyclooctene oxide are higher.

As can be seen from comparing CAT-1 to CAT11 with CAT-12, T of CAT-1 to CAT11 ₀ The value of (C) is between 0.55 and 0.85eV, CAThe conversion rate of the cyclooctene, the conversion rate of the isobutyraldehyde and the selectivity of the cyclooctene of the T-1 to CAT-11 are higher.

The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings, but the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solutions of the present disclosure within the scope of the technical concept of the present disclosure, and all the simple modifications belong to the protection scope of the present disclosure.

In addition, the specific features described in the above embodiments may be combined in any suitable manner without contradiction. The various possible combinations are not described further in this disclosure in order to avoid unnecessary repetition.

Moreover, any combination between the various embodiments of the present disclosure is possible as long as it does not depart from the spirit of the present disclosure, which should also be construed as the disclosure of the present disclosure.

Claims (18)

1. The composite catalytic material of the metal nano particles and the molecular sieve is characterized by comprising an all-silicon molecular sieve and metal elements M dispersed in crystals of the all-silicon molecular sieve; the metal element M is a metal element capable of forming an oxide aggregate;

the composite catalytic material has the following XPS characteristics:

the electron binding energy of the metal element M in the composite catalytic material is denoted as T ₁ ，

The electron binding energy of the metal element M in the oxide aggregate is denoted as T ₂ ，

T as defined by the following formula (1) ₀ Is any value between 0.5 and 1.0 eV;

T ₀ ＝T ₁ -T ₂ formula (1).

2. The composite catalytic material of claim 1, wherein T ₀ The value of (2) is any value between 0.55 and 0.85 eV.

3. The composite catalytic material of claim 1, wherein the all-silicon molecular sieve in the composite catalytic material is at least one of an MFI structure molecular sieve, a MEL structure molecular sieve, a BEA structure molecular sieve, an MWW structure molecular sieve, a two-dimensional hexagonal structure molecular sieve, a MOR structure molecular sieve, and a TUN structure molecular sieve; preferably one or more selected from MFI structure molecular sieve, MEL structure molecular sieve, BEA structure molecular sieve, MCM structure molecular sieve and SBA structure molecular sieve; further preferably one or more of MFI structure molecular sieve, MEL structure molecular sieve and BEA structure molecular sieve;

The metal M is selected from one or more of manganese, iron, cobalt, nickel, palladium, platinum, copper and gold.

4. The composite catalytic material of claim 3, wherein the metal M is Co and the oxide aggregates are Co ₃ O ₄ An aggregate;

the metal M is Mn, and the oxide aggregate is MnO ₂ An aggregate;

the metal M is Fe, and the oxide aggregate is Fe ₂ O ₃ An aggregate;

the metal M is Ni, and the oxide aggregate is NiO aggregate;

the metal M is Pd, and the oxide aggregate is a PdO aggregate;

the metal M is Pt, and the oxide aggregate is PtO ₂ An aggregate; or alternatively, the process may be performed,

the metal M is Cu, and the oxide aggregate is a CuO aggregate;

preferably, when the metal element M is Co, mn, fe, ni or Cu, the electron binding energy of the metal element M is 2p of the metal element M _3/2 Binding energy of electrons; when the metal element M is Pt, the electron binding energy of the metal element M is 4f of the metal element M _7/2 Binding energy of electrons; when the metal element M is Pd, the electron binding energy of the metal element M is 3d of the metal element M _5/2 Binding energy of electrons.

5. The composite catalytic material according to claim 1, wherein the molar ratio of the metal M element to the silicon element is (0.001 to 0.2): 1, preferably (0.001 to 0.15): 1.

6. The composite catalytic material according to claim 1, wherein the BET specific surface area of the composite catalytic material is 400 to 800m ² Per gram, the total pore volume is 0.3-0.65 mL/g, the micropore volume is 0.1-0.19 mL/g, and the mesopore volume is 0.15-0.46 mL/g; the metal element M in the composite catalytic material exists in the form of metal nano particles, and the average particle size of the metal nano particles is 0.5-10 nm.

7. A method for preparing a metal nanoparticle and molecular sieve composite catalytic material, comprising the steps of:

s1, mixing a template agent, a silicon source, water, a metal M precursor, a silanization reagent and a structural filler to obtain a reaction mixture, wherein the structural filler is an amphiphilic surfactant and/or a hard template agent;

s2, carrying out hydrothermal crystallization treatment and roasting treatment on the reaction mixture.

8. The method of claim 7, wherein in step S1, the silicon source: template agent: water: metal M element: the molar ratio of the silylating agent is 1: (0.001-1): (5-100): (0.001-0.2): (0.025-0.4); preferably 1: (0.005-0.5): (5-100): (0.001-0.15): (0.025-0.3); siO in the reaction mixture ₂ The weight ratio of the structural filler to the structural filler is (3-100): 1.

9. the method according to claim 7, wherein step S1 comprises:

a. mixing a template agent, a silicon source and water to obtain a silicon hydrolysis solution;

b. mixing a metal M precursor and the silicon hydrolysis solution to obtain a first mixed material;

c. respectively adding a silylation reagent and a structural filler into the first mixed material, and mixing to obtain a reaction mixture; preferably, the conditions of mixing in step c include: stirring at 20-80 deg.c for 0.5-2 hr.

10. The method of claim 7, wherein the silicon source is selected from at least one of silicone grease, solid silica gel, white carbon black, and silica sol; preferably at least one selected from the group consisting of silicone grease, solid silica gel and white carbon black;

further preferred is a silicone grease having a structure represented by the following formula (A):

wherein R is _a 、R _b 、R _c 、R _d Each independently selected from alkyl groups having 1 to 6 carbon atoms, said alkyl groups being branched or straight chain alkyl groups; preferably, R _a 、R _b 、R _c 、R _d Each independently selected from a straight chain alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 to 4 carbon atoms; further preferably, the R _a 、R _b 、R _c 、R _d Each independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, or tert-butyl; further preferably, the organic silicone grease is selected from one or more of tetramethyl silicate, tetraethyl silicate, tetrabutyl silicate and dimethyl diethyl silicone grease.

11. The method according to claim 7, wherein in step S1, the template agent is an organic base, preferably at least one selected from the group consisting of quaternary ammonium bases, aliphatic amines and aliphatic alcohol amines;

further preferably, the template is at least one selected from structural quaternary ammonium bases represented by the following formula (B):

R ₁ 、R ₂ 、R ₃ and R is ₄ Each selected from alkyl groups having 1 to 4 carbon atoms, preferably straight chain alkyl groups having 1 to 4 carbon atoms and branched alkyl groups having 3 to 4 carbon atoms, more preferably R ₁ 、R ₂ 、R ₃ And R is ₄ At least one selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl and tert-butyl;

further preferably, the all-silicon molecular sieve is an MFI type molecular sieve, and the template agent is tetrapropylammonium hydroxide or a mixture of tetrapropylammonium hydroxide and one or more selected from tetrapropylammonium chloride and tetrapropylammonium bromide; or the all-silicon molecular sieve is a MEL molecular sieve, and the template agent is tetrabutylammonium hydroxide or a mixture of tetrabutylammonium hydroxide and one or more selected from tetrabutylammonium chloride and tetrabutylammonium bromide; or the molecular sieve is Beta-type molecular sieve, and the template agent is tetraethylammonium hydroxide or a mixture of tetraethylammonium hydroxide and one or more selected from tetraethylammonium chloride and tetraethylammonium bromide.

12. The method according to claim 9, wherein in step a, the silicon source is an organic silicone grease, and further comprising hydrolysis alcohol removal treatment after mixing the template agent, the organic silicone grease and water to obtain a hydrolysis solution of the silicon;

the conditions for the hydrolysis alcohol expelling treatment comprise: stirring and hydrolyzing for 2-10 hours at 0-95 ℃; preferably at 50-95 deg.C for 2-8 hr.

13. The method according to claim 7, wherein in step S1, the metal M precursor is one or more of an inorganic metal compound and an organic metal compound; the inorganic metal compound is water-soluble inorganic salt of metal M; the water-soluble inorganic salt of the metal M is selected from one or more of chloride, hydrated chloride, sulfate, hydrated sulfate and nitrate of the metal M; the organic metal compound is an organic ligand compound of metal M; preferably, the metal M precursor is a water-soluble inorganic salt of metal M;

the metal M is selected from one or more of manganese, iron, cobalt, nickel, palladium, platinum, copper and gold;

preferably, the metal M precursor is in the form of an aqueous solution of the metal M precursor, and the molar ratio of the metal M element to water in the aqueous solution of the metal M precursor is 1: (50-500).

14. The method of claim 7, wherein in step S1, the silylating agent has the general formula R ₅ Si(R ₆ )(R ₇ )R ₈ Wherein R is ₅ 、R ₆ 、R ₇ 、R ₈ Each independently is halogen, alkyl, alkoxy, aryl, mercapto or amino, and R ₅ 、R ₆ 、R ₇ 、R ₈ At least one of which is alkyl, alkoxy, aryl, mercapto or amino; the carbon atoms of the alkyl, alkoxy, mercapto and amino are each independently any integer from 1 to 18, and the carbon atoms of the aryl are each any integer from 6 to 18;

preferably, the silylating agent is selected from one or more of dimethyldichlorosilane, N-phenyl-3-aminopropyl trimethoxysilane, phenyl trimethoxysilane, 1, 7-dichlorooctanethyltetrasiloxane, hexadecyl trimethoxysilane, octyl triethoxysilane, 3-aminopropyl trimethoxysilane, N-beta- (aminoethyl) -gamma-aminopropyl trimethoxysilane and 3-mercaptopropyl trimethoxysilane; further preferably one or more selected from the group consisting of N-phenyl-3-aminopropyl trimethoxysilane, N-beta- (aminoethyl) -gamma-aminopropyl trimethoxysilane and 3-mercaptopropyl trimethoxysilane.

15. The method according to claim 7, wherein in step S1, the structural filler is selected from one or more of cetyltrimethylammonium bromide, sodium dodecylbenzenesulfonate, PEO-PPO-PEO triblock copolymer, mesoporous carbon and natural cellulose.

16. The method according to claim 7, wherein in step S2, the conditions of the hydrothermal crystallization treatment include: under autogenous pressure, the hydrothermal crystallization time is 0.5-10 days, and the hydrothermal crystallization temperature is 110-200 ℃; preferably, the hydrothermal crystallization time is 0.5-5 days, and the hydrothermal crystallization temperature is 150-200 ℃;

the conditions of the calcination treatment include: roasting temperature is 400-900 ℃ and roasting time is 1-16 hours; preferably, the roasting temperature is 400-800 ℃ and the roasting time is 2-8 hours.

17. A metal nanoparticle and molecular sieve composite catalytic material prepared according to the method of any one of claims 7 to 16.

18. Use of the metal nanoparticle of any one of claims 1 to 6 or the metal nanoparticle of claim 17 in combination with a molecular sieve composite catalytic material for catalyzing the co-oxidation of macromolecular aldehydes/olefins; preferably in catalyzing the co-oxidation of cyclooctene and isobutyraldehyde.

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