Composite molecular sieve catalyst, preparation method and catalytic reaction device

Abstract

The invention provides a composite molecular sieve catalyst, a preparation method and a catalytic reaction device, the composite molecular sieve catalyst comprises a molecular sieve, perovskite and a conductive carbon material, the perovskite and the conductive carbon material are loaded on at least part of the surface of the molecular sieve, and the surface of the conductive carbon material comprises a connecting functional group; at least part of the connecting functional groups are connected with the molecular sieve. The composite molecular sieve catalyst provided by the invention has high conductivity and excellent catalytic performance, realizes the synergistic effect of conductivity, catalyst acidity and hydrogenation activity, and is used for improving the reaction thermal efficiency, so that energy can be supplied in an electric-thermal conversion mode, and carbon emission is reduced.

Description

Technical Field

[0001] This invention relates to the field of catalysts, and more particularly to a composite molecular sieve catalyst, its preparation method, and a catalytic reaction apparatus. Background Technology

[0002] The petrochemical industry is a vital pillar of the national economy, but traditional petrochemical processes rely on fossil fuels for heating, resulting in low thermal efficiency, high carbon emissions, and slow temperature response. With the rapid development of renewable energy, electricity supply capacity has significantly improved. Driven by the "dual carbon" goal (carbon reduction and emission reduction), introducing electricity into petrochemical production and using it to directly drive catalytic reactions, replacing traditional combustion heating with electrothermal catalysis technology, can substantially reduce carbon emissions and improve energy efficiency.

[0003] Molecular sieves are core catalysts in petrochemical reactions, but their insulating properties have become a key bottleneck restricting the application of electrothermal catalysis. Current technologies mostly rely on external heating sources and have not yet achieved a purely electrically driven reaction mode. In traditional electrothermal catalytic systems, metal-based catalysts are the mainstream conductive catalytic materials, but these catalysts have limitations; their catalytic performance is poor when directly applied to petrochemical reactions, and they are not effectively compatible with molecular sieve catalytic systems. How to construct an electrothermal catalytic system adapted to molecular sieves based on electric drive remains a pressing technical challenge in the petrochemical field.

[0004] Therefore, addressing the issues of high carbon emissions and low thermal efficiency in existing catalytic systems using fuel heating is a key requirement for the green transformation of the petrochemical industry. Summary of the Invention

[0005] This invention provides a composite molecular sieve catalyst with good electrical conductivity and catalytic activity, achieving a synergistic effect of electrical conductivity, catalyst acidity and hydrogenation activity to improve reaction thermal efficiency, thereby providing energy through electrothermal conversion and reducing carbon emissions.

[0006] The present invention also provides a method for preparing a composite molecular sieve catalyst, which can prepare the above-mentioned composite molecular sieve catalyst.

[0007] The present invention also provides a catalytic reaction apparatus, which provides a reaction apparatus for using the above-mentioned composite molecular sieve catalyst to carry out catalytic reactions.

[0008] In a first aspect, the present invention provides a composite molecular sieve catalyst comprising a molecular sieve and a perovskite and conductive carbon material supported on at least a portion of the surface of the molecular sieve, wherein the surface of the conductive carbon material includes connecting functional groups; at least a portion of the connecting functional groups are connected to the molecular sieve.

[0009] Furthermore, the mass ratio of the conductive carbon material, perovskite, and molecular sieve is (1~6):(4~70):1.

[0010] Furthermore, the connecting functional group includes at least one of the following: amino, imino, amide, cyano, nitro, pyridyl, nitroso, hydroxyl, carboxyl, and epoxy groups.

[0011] Furthermore, the conductive carbon material comprises at least one of ordered mesoporous carbon, graphite, activated carbon, carbon nanotubes, graphene, and carbon aerogel.

[0012] Furthermore, the chemical formula of the perovskite is ABO3, wherein A includes La. 3+ Ba 2+ 、Nd 3+ Y 3+ At least one of them, B includes Cu 2+ Co 2+ Ni 2+ Fe 3+ Zn 2+ Mn 2+ At least one of them.

[0013] Furthermore, the molecular sieve includes at least one of ZSM molecular sieve, Beta molecular sieve, SAPO molecular sieve, MOR molecular sieve, and Y-type molecular sieve.

[0014] Secondly, the present invention provides a method for preparing a composite molecular sieve catalyst, comprising the following steps:

[0015] The carbon source is etched with acid and then sintered in one step to obtain a conductive carbon material with the aforementioned connecting functional groups on its surface.

[0016] The composite molecular sieve catalyst is obtained by combining the perovskite, the conductive carbon material with interconnected functional groups on its surface, and the molecular sieve.

[0017] Furthermore, the primary sintering process specifically includes the following steps: under a nitrogen flow rate of 5-30 mL / min, the temperature is raised to 400-900 ℃ at a heating rate of 1-5 ℃ / min, and held at that temperature for 2-6 h.

[0018] The composite method includes mechanical mixing or a single hydrothermal treatment;

[0019] The composite process further includes a secondary hydrothermal treatment and a tertiary sintering treatment; wherein the secondary hydrothermal treatment is performed at a temperature of 120~220 ℃ for a time of 6~20 h; the tertiary sintering treatment includes sintering at 400~600 ℃ for 1~6 h.

[0020] Furthermore, the perovskite is prepared by a method comprising the following process: subjecting a mixed system comprising a solvent, a metal source, citric acid and a polyol to a secondary sintering treatment to obtain the perovskite; the metal source comprises metal A and metal B; the molar ratio of the metal source, citric acid and polyol is 2 : (1~2) : (2~6);

[0021] Preferably, the secondary sintering treatment specifically includes the following process: heating from room temperature to 200-300 ℃ at a heating rate of 1-10 ℃ / min, holding at that temperature for 1-2 h, then heating to 600-800 ℃, and holding at that temperature for 2-4 h.

[0022] Thirdly, the present invention provides a catalytic reaction apparatus comprising a power source, an insulated reactor, and a catalytic bed, wherein the catalytic bed is disposed within the insulated reactor; the catalytic bed comprises the composite molecular sieve catalyst described in the first aspect.

[0023] The composite molecular sieve catalyst provided by this invention, wherein the perovskite and conductive carbon materials prepared by this invention have good conductivity, and the perovskite can simultaneously provide dehydrogenation sites, thereby improving the conductivity and catalytic activity of the composite molecular sieve catalyst through the synergistic effect of conductivity, molecular sieve acid activation and hydrogenation activity, and enabling energy to be supplied through electrothermal conversion. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the accompanying drawings used in the description of the embodiments of the present invention or related technologies are briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 A schematic diagram of a catalytic reaction apparatus for a specific embodiment;

[0026] Figure 2 This is an infrared thermal image of the catalytic reaction apparatus of Example 1;

[0027] Figure 3 The images show the XRD patterns of the perovskite LaCuO3 obtained in Example 1, the perovskite LaCoO3 obtained in Example 8, and the ordered mesoporous carbon CMK-3 obtained in Example 1. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below. The specific embodiments listed below are merely descriptions of the principles and features of the present invention, and the examples are only for explaining the present invention and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] In a first aspect, the present invention provides a composite molecular sieve catalyst comprising a molecular sieve and perovskite and conductive carbon materials supported on at least a portion of the surface of the molecular sieve; the surface of the conductive carbon material includes connecting functional groups; at least a portion of the connecting functional groups are connected to the molecular sieve.

[0030] The surface of a conductive carbon material refers to a surface in which at least a portion of the material's surface includes connecting functional groups. Regarding the positional relationship between perovskite and conductive carbon materials, this invention does not impose any particular limitation. In some embodiments, perovskite includes, but is not limited to, being dispersed on the surface (including the inner and / or outer surfaces of the pores) and in the gaps of the molecular sieve. The gaps between the perovskite and the molecular sieve are at least partially filled with conductive carbon materials. The three interact closely through the connecting functional groups (such as hydrogen bonds or coordination bonds formed between the hydroxyl groups on the conductive carbon surface and the silanol groups on the molecular sieve, and between the metal ions on the perovskite surface), achieving spatial contact and ultimately constructing a three-dimensional structure of interconnected "conductive carbon materials-perovskite-molecular sieve" within the entire catalyst system. Since both perovskite and conductive carbon materials have good conductivity, after they form spatial contact with the molecular sieve components, they construct a continuous conductive network covering the entire catalyst. When the reaction system is energized, the current is transmitted along this network, and free electrons within the catalyst move directionally under the action of the electric field and collide with the crystal lattice, converting electrical energy into Joule heat. This achieves rapid in-situ heating of the system, reduces heat loss, improves heat utilization efficiency, and ultimately achieves the effect of uniform catalytic reaction without an external heat source. In this composite molecular sieve catalyst, the molecular sieve component, relying on its regular pore structure and acidic sites, can achieve shape-selective catalysis of reactants, avoiding over-reaction. Perovskite metal ions, in addition to helping construct the conductive network, also possess addition and dehydrogenation reactivity due to their variable valence states and d-orbital characteristics, thus aiding in the completion of specific target reactions. Throughout the process, the molecular sieve not only performs a sieving function but also participates in reactant activation through its active sites, synergistically achieving a complete catalytic cycle of "shape-selective sieving - adsorption activation - high-efficiency reaction" with the perovskite, making it suitable for various catalytic scenarios.

[0031] For example, perovskite is uniformly dispersed in the molecular sieve surface and interstices in the form of flakes, fibers or granules, and conductive carbon material is uniformly filled in the gaps between the molecular sieve and the perovskite in the form of flakes, fibers or granules.

[0032] In a preferred embodiment, the mass ratio of the conductive carbon material, perovskite, and molecular sieve is (1~6):(4~10):1. This ratio range further ensures that the composite molecular sieve catalyst achieves a synergistic effect of conductivity, acidity, and hydrogenation activity. Specifically, this ratio range ensures optimal spatial dispersion and functional synergy among the three components in the composite molecular sieve catalyst. This means that a reasonable ratio allows perovskite particles to uniformly fill the surface and interstices of the molecular sieve, preventing agglomeration due to excessive perovskite content that masks the active sites of the molecular sieve, or insufficient conductivity or catalytic performance due to insufficient perovskite content. Simultaneously, it ensures that conductive carbon material fills the interfacial voids at an appropriate level, sufficient to construct a continuous conductive network covering the entire catalyst, ensuring efficient conversion of electrical energy into Joule heat or smooth charge transfer, while avoiding excessive carbon material clogging the molecular sieve channels, thus maintaining good mass transfer efficiency. Furthermore, it fixes the bulk proportion of the molecular sieve, ensuring its full role as the core active carrier in the catalytic reaction is fully realized. Ultimately, this allows the composite molecular sieve catalyst to achieve a balance between conductivity, catalytic activity, mass transfer efficiency, and structural stability, providing clear parameter guidelines for the large-scale preparation and industrial application of the catalyst, and ensuring the consistency and reliability of performance across different batches of products.

[0033] For example, the mass ratio of conductive carbon material, perovskite and molecular sieve is 1:4:1, 1:5:1, 1:6:1, 1:7:1, 1:8:1, 1:9:1, 1:10:1, 3:4:1, 3:5:1, 3:6:1, 3:7:1, 3:8:1, 3:9:1, 3:10:1, 6:4:1, 6:5:1, 6:6:1, 6:7:1, 6:8:1, 6:9:1, 6:10:1, preferably 3:4:1.

[0034] The present invention does not specifically limit the application scenarios of the above-mentioned composite molecular sieve catalyst. Due to its advantages, in some embodiments, the composite molecular sieve catalyst of the present invention can be used for catalytic cracking reactions, isomerization reactions, aromatization reactions, and hydrocracking reactions with molecular sieve as the active phase.

[0035] For example, in catalytic cracking reactions (such as the catalytic cracking of heavy oil to produce light olefins), molecular sieves achieve "shape-selective sieving" based on their regular microporous structure, allowing only appropriately sized large hydrocarbon molecules in the heavy oil to enter the pores and break down the large molecular chains into smaller intermediates through their own acidic sites; simultaneously, perovskites (such as LaFeO3) can, under the influence of an electric field, utilize Fe... 3+ / Fe 2+The valence state cycling assists in activating C-C bonds, lowering the activation energy of the pyrolysis reaction. The continuous network constructed from conductive carbon materials can generate Joule heat through electric current, providing the necessary high-temperature environment (typically 500~600℃) for the pyrolysis reaction. When composite molecular sieve catalysts are used in catalytic pyrolysis reactions, the reaction system does not require an external heat source, avoiding heat loss. At the same time, their high conductivity can reduce the deposition of carbon precursors in the molecular sieve channels during the reaction, extending the service life of the composite molecular sieve catalyst.

[0036] For example, in isomerization reactions (such as the isomerization of n-butane to isobutane), the acidic sites of the molecular sieve (such as the Brønsted acid sites of ZSM-5) are responsible for adsorbing n-butane and catalyzing its carbon chain skeleton rearrangement, while perovskite assists in dehydrogenation to form reaction intermediates. The conductive carbon material, on the one hand, forms a strong interfacial bond with the molecular sieve through hydroxyl groups, preventing the loss of active sites due to perovskite particle aggregation; on the other hand, its constructed conductive network can quickly compensate for heat loss through Joule heating when the reaction requires temperature fine-tuning (isomerization reactions typically require 150~250℃), maintaining a stable reaction system temperature and ensuring isomerization efficiency. Simultaneously, the presence of an external electric field can promote the formation of reaction intermediates through electron transfer. When composite molecular sieve catalysts are used in isomerization reactions, the reaction system does not require an external heat source, avoiding heat loss. Furthermore, their high conductivity can reduce the deposition of carbon precursors in the molecular sieve channels during the reaction, extending the lifespan of the composite molecular sieve catalyst.

[0037] For example, in aromatization reactions (such as the aromatization of low-carbon olefins to prepare benzene, toluene, and xylene), the shape-selective pore structure of HZSM-5 molecular sieves creates a steric confinement effect on reactants and intermediates, limiting their diffusion paths and thus selectively guiding the reaction towards the formation of benzene, toluene, and xylene (BTX); the Co of perovskites (such as LaCoO3) 3+ It can serve as a dehydrogenation active center, assisting in the dehydrogenation of cyclization intermediates to form aromatic rings and improving the aromatization conversion rate. Conductive carbon materials not only promote electron transfer in the reaction through high conductivity (accelerating the dehydrogenation process), but also utilize their high specific surface area to disperse perovskite active sites, avoiding deep dehydrogenation and carbon deposition of low-carbon olefins due to active site aggregation. Simultaneously, the hierarchical porous structure formed by it and the molecular sieve can reduce the diffusion resistance of aromatic products and decrease secondary reactions of products within the pores. When composite molecular sieve catalysts are used in aromatization reactions, the reaction system does not require an external heat source, avoiding heat loss. Furthermore, its high conductivity can reduce the deposition of carbon precursors in the molecular sieve pores during the reaction, extending the service life of the composite molecular sieve catalyst.

[0038] For example, in hydrocracking reactions (such as vacuum gas oil hydrocracking to produce diesel and gasoline), the acidic sites of the molecular sieve are responsible for catalyzing hydrocarbon cracking, while perovskite can assist H2 activation to generate active hydrogen species by loading metal active components, promoting the hydrogenation saturation of cracking products; the conductive network constructed by conductive carbon materials can provide a stable heat source for the reaction through Joule heat converted from electrical energy when the reaction requires mild heating (hydrocracking usually requires 300~400℃), while its good conductivity can promote the migration of active hydrogen species on the surface of the composite molecular sieve catalyst, improving hydrogenation efficiency, and the anti-coking performance of carbon materials can reduce the coverage of acidic sites of molecular sieve by carbon deposits during cracking, extending the operating cycle of the composite molecular sieve catalyst.

[0039] For example, in electrocatalytic dehydrogenation reactions, if the reaction requires higher temperatures, "charge transfer" and "Joule heating" can be achieved simultaneously through the same conductive network. In this case, the composite molecular sieve catalyst has the dual function of electrocatalysis (charge participating in the reaction) and electric heating (thermal energy assisting the reaction).

[0040] In a preferred embodiment, the surface of the conductive carbon material includes connecting functional groups, which include at least one of the following: amino-NH2, imino-NH-, amide-CONH2, cyano-CN, nitro-NO2, pyridyl-C5H4N-, nitroso-NO, hydroxyl-OH, carboxyl-COOH, and epoxy-COC. By forming hydrogen bonds or Si-OC covalent bonds with the silanol and aluminol hydroxyl groups on the molecular sieve surface through the connecting functional groups, the interfacial bonding between the conductive carbon material and the molecular sieve is strengthened to suppress component separation.

[0041] In this invention, the surface of the conductive carbon material includes connecting functional groups, which further ensures that, on the one hand, the functional groups enhance the interfacial bonding between the conductive carbon material and the molecular sieve to promote charge transfer and reduce charge loss at the interface. By utilizing nitrogen doping sites and hydroxyl groups to regulate the surface electronic state and optimize the π electron density, the conductivity of the conductive carbon material and the overall composite molecular sieve catalyst is improved. On the other hand, the enhanced interfacial bonding between the connecting functional groups and the perovskite and molecular sieve allows the conductive carbon material to act as a "charge bridge," that is, as an auxiliary active site to synergistically construct a catalytic center with the active sites of the molecular sieve, transferring electrons from the external circuit to the perovskite dehydrogenation active sites, promoting redox reactions, and thus improving the catalytic activity of the composite molecular sieve catalyst.

[0042] In a preferred embodiment, the conductive carbon material comprises at least one of ordered mesoporous carbon, graphite, activated carbon, carbon nanotubes, graphene, and carbon aerogel.

[0043] In this invention, conductive carbon materials of different materials all possess electrical conductivity. The introduction of conductive carbon materials can, on the one hand, bring good conductivity to the composite molecular sieve catalyst, and on the other hand, the conductive carbon materials can also support the molecular sieve and adsorb carbon deposition precursors, thereby improving the stability and anti-carbon deposition ability of the composite molecular sieve catalyst. The application scenarios of the above-mentioned conductive carbon materials are not particularly limited in this invention. Due to its above-mentioned advantages, in some embodiments, the conductive carbon materials of this invention can be selected as needed to adapt to different catalytic reaction requirements.

[0044] For example, when ordered mesoporous carbon is used as the conductive carbon material, it has a regular mesoporous structure, a moderate degree of graphitization, and few surface defects. When combined with molecular sieves, its regular mesoporous structure can form a "hierarchical pore network" with the molecular sieve channels, enhancing mass transfer efficiency. This allows the composite molecular sieve catalyst containing this conductive carbon material to possess both high conductivity and excellent catalytic performance, enabling energy supply via electrothermal conversion.

[0045] For example, when carbon nanotubes and activated carbon are combined as conductive carbon materials, the carbon nanotubes, with their hollow tubular structure, high degree of graphitization, and large aspect ratio, provide efficient conductive pathways by concentrating surface defects at the tube ends and sidewall imperfections, thus compensating for the insufficient conductivity of activated carbon. Activated carbon, a mixture of amorphous carbon and a small amount of graphite microcrystals, has a large specific surface area and numerous surface defects. Its high specific surface area and abundant functional groups enhance the interfacial bonding with the molecular sieve, compensating for the lack of functional groups in the carbon nanotubes. Simultaneously, the hierarchical porous structure formed by both materials improves mass transfer efficiency, making it suitable for scenarios requiring high conductivity and high dispersibility, such as electrocatalytic dehydrogenation. Therefore, the composite molecular sieve catalyst containing this conductive carbon material possesses both high conductivity and excellent catalytic performance, enabling energy supply via electrothermal conversion.

[0046] For example, in the electrothermal catalytic cracking reaction of heavy oil, when a combination of carbon nanotubes and ordered mesoporous carbon is used as the conductive carbon material, the carbon nanotubes, with their high graphitization structure and aspect ratio, construct continuous conductive pathways, efficiently converting electrical energy into Joule heat and ensuring the high temperature required for the reaction. The ordered mesoporous carbon, with its regular mesopores and molecular sieves, forms a multi-level pore network, solving the problem of carbon nanotubes easily agglomerating and clogging the pores, thus facilitating the mass transfer of heavy oil macromolecules and the discharge of light olefin products. The synergy of the two satisfies both the electrothermal efficiency and ensures smooth mass transfer, improving the conversion rate of heavy oil and reducing reaction energy consumption compared to a single carbon material. Therefore, the composite molecular sieve catalyst containing this conductive carbon material possesses both high conductivity and excellent catalytic performance, enabling energy supply through electrothermal conversion.

[0047] In a preferred embodiment, the perovskite has the chemical formula ABO3, wherein A includes La. 3+ Ba 2+ 、Nd 3+ Y 3+At least one of them, B includes Cu 2+ Co 2+ Ni 2+ Fe 3+ Zn 2+ Mn 2+ At least one of them.

[0048] For example, the chemical formula of perovskite is ABO3, where A stands for La. 3+ Ba 2+ 、Nd 3+ Y 3+ In any one of them, B is Cu 2 + Co 2+ Ni 2+ Fe 3+ Zn 2+ Mn 2+ Any one of them.

[0049] The core structure of the perovskite described above is an ABO3-type three-dimensional crystal framework. B-site metal cations and oxygen ions form BO6 octahedra, which are connected to form a three-dimensional network through shared oxygen vertices. A-site metal ions fill the interstices of the network to balance the charge and stabilize the structure. This three-dimensional octahedral network can serve as a "secondary channel" for charge transport. Simultaneously, the rigidity of the three-dimensional octahedral network and the flexible replacement of interstitial metal ions endow the material with high stability and structural tolerance, allowing for performance modulation through elemental combinations. Furthermore, the continuous octahedral network provides migration channels for electrons (or ions), enabling efficient charge transport through orbital coupling between metal and oxygen, thus giving the material conductivity. In addition, perovskites, relying on the variable valence state and d-orbital characteristics of B-site transition metal ions, provide catalytic functions such as dehydrogenation, oxidation, and electron transfer. For example, B-site ions can assist in dehydrogenation or activate oxidants through valence state cycling and electron transfer. Thus, the composite molecular sieve catalyst contains the aforementioned perovskite with good conductivity and catalytic activity, which promotes charge transport in the reaction system, provides dehydrogenation sites for the composite molecular sieve catalyst, expands the application range of the composite molecular sieve catalyst in catalytic reactions, and makes it suitable for electrocatalysis, photocatalysis and other scenarios.

[0050] In a preferred embodiment, the molecular sieve comprises at least one of ZSM molecular sieve, Beta molecular sieve, SAPO molecular sieve, MOR molecular sieve, and Y-type molecular sieve.

[0051] In some embodiments, the silica-to-alumina ratio of ZSM series molecular sieves is 25~1000, the silica-to-alumina ratio of Beta series molecular sieves is 20~100, the silica-to-alumina ratio of SAPO series molecular sieves is 0.4~0.8, the silica-to-alumina ratio of MOR series molecular sieves is 4.17~5, and the silica-to-alumina ratio of Y series molecular sieves is 2.5~6.

[0052] In this invention, the aforementioned molecular sieve serves as the core catalytic center of the composite molecular sieve catalyst. It achieves shape-selective sieving through its regular channels, allowing only reactants of matching size to enter and suppressing macromolecular side reactions to enhance selectivity. Furthermore, its high specific surface area disperses perovskite and conductive carbon materials, preventing agglomeration that could lead to loss of active sites or interruption of conductive pathways. Simultaneously, its surface hydroxyl groups form interfacial interactions with the perovskite and conductive carbon materials, enhancing structural stability. Ultimately, the molecular sieve, perovskite, and conductive carbon materials synergistically improve catalytic selectivity, efficiency, and stability, making it suitable for various catalytic scenarios. Thus, the composite molecular sieve catalyst containing this molecular sieve possesses both high conductivity and excellent catalytic performance, enabling energy supply via electrothermal conversion.

[0053] As for the particle size of molecular sieves, perovskites and conductive carbon materials, the present invention does not impose any particular limitation. For example, the particle size of molecular sieves is 0.01 μm to 10 μm, the particle size of perovskites is 20 nm to 500 nm, and the particle size of conductive carbon materials is 0.6 nm to 200 nm.

[0054] Secondly, the present invention provides a method for preparing the above-mentioned composite molecular sieve catalyst, comprising the following steps:

[0055] The carbon source is etched with acid and then sintered once to obtain a conductive carbon material with interconnected functional groups on the surface.

[0056] A composite molecular sieve catalyst is obtained by combining perovskite, conductive carbon material with surface-connecting functional groups, and molecular sieve.

[0057] In this invention, the connecting functional groups include: oxygen-containing and nitrogen-containing functional groups obtained by etching a carbon source with acid, and nitrogen-containing functional groups introduced by a single sintering process. Different types of acid etching can introduce different functional groups; for example, nitric acid etching can introduce nitrogen-containing functional groups.

[0058] The above etching process can, through the defect sites on the surface of carbon oxide materials, increase oxygen-containing (such as -OH, -COOH) and nitrogen-containing (such as -NH2, pyridyl) functional groups, which can form hydrogen bonds or chemical bonds with hydroxyl groups on the surface of molecular sieves. At the same time, it increases the surface roughness of carbon materials to strengthen mechanical interlocking, thereby enhancing the bonding with molecular sieves. On the other hand, it removes surface impurities and clears conductive pathways to improve conductivity.

[0059] In some embodiments, the acid is either HNO3 or H2SO4.

[0060] In some embodiments, the primary sintering process specifically includes the following steps: heating to 400-900 °C at a nitrogen flow rate of 5-30 mL / min and a heating rate of 1-5 °C / min, and holding at that temperature for 2-6 h.

[0061] The composite methods include mechanical mixing or single hydrothermal treatment;

[0062] After the composite process, a second hydrothermal treatment and a third sintering treatment are also performed. The temperature of the second hydrothermal treatment is 120~220 ℃ and the time is 6~20 h. The third sintering treatment includes sintering at 400~600 ℃ for 1~6 h.

[0063] In some embodiments, the above-mentioned primary sintering process also includes heating from room temperature to 400-900 °C.

[0064] In some embodiments, the nitrogen flow rate during the primary sintering process effectively removes residual moisture and small molecule byproducts from the etching process, preventing structural defects caused by bubbles. Slow heating and sufficient heat preservation promote the formation of a dense and uniform skeletal structure in the carbon material, reducing microcracks caused by thermal stress and improving the material's mechanical stability and molding integrity. High-temperature nitrogen treatment retains the aforementioned connecting functional groups (the functional groups on the surface of the conductive carbon material generated after etching the carbon source) while introducing new nitrogen-containing functional groups. These groups can form interfacial interactions (hydrogen bonds or coordination bonds) with the silanol groups and perovskite metal ions on the molecular sieve surface, significantly enhancing the bonding strength between the three and reducing the interfacial charge barrier. Heat treatment promotes increased graphitization of the conductive carbon material and a more complete π-conjugated system; simultaneously, it removes disordered carbon and impurities from the surface, reducing electron transport resistance and providing a good conductive foundation for applications such as electrothermal catalysis.

[0065] For example, when ordered mesoporous carbon is used as a conductive carbon material, it initially has a regular mesoporous structure (pore size 2~50 nm), moderate graphitization, and few surface defects. After acid etching, the mesoporous pore walls are etched, introducing a moderate density of hydroxyl groups (-OH) and a small amount of carboxyl groups (-COOH). After high-temperature calcination under nitrogen, the more stable hydroxyl groups are retained. The hydroxyl groups combine with the silanol groups of the molecular sieve through hydrogen bonds, improving interfacial stability. At the same time, acid etching has limited damage to its conjugated structure, while removing disordered carbon and impurities from the surface, reducing electron transport resistance. The regularized pores are more conducive to forming contact with the molecular sieve, and the conductivity is basically stable, providing a good conductive basis for applications such as electrothermal catalysis.

[0066] For example, the nitrogen flow rate during the first sintering can be 5 mL / min, 10 mL / min, 15 mL / min, 20 mL / min, 25 mL / min, or 30 mL / min, preferably 25 mL / min.

[0067] For example, the heating rate of the above-mentioned first sintering can be 1 ℃ / min, 2 ℃ / min, 3 ℃ / min, 4 ℃ / min, or 5 ℃ / min, preferably 2 ℃ / min.

[0068] For example, the first heat preservation time for the first sintering can be 2 h, 3 h, 4 h, 5 h, or 6 h, preferably 4 h.

[0069] In a preferred embodiment, the above-mentioned composite method is a mechanical mixing method. Specifically, molecular sieve, conductive carbon material, perovskite and solvent are mixed and ultrasonically dispersed for 0.5 to 2 hours. After ultrasonication, stirring is continued for 1 to 6 hours.

[0070] The mechanical mixing method used in the above preparation method is convenient and allows for flexible control of the loading of conductive carbon materials and perovskite. At the same time, physical composite relies only on van der Waals forces and mechanical interlocking, which will not damage the microporous / mesoporous structure of the molecular sieve. It can fully preserve its shape-selective catalytic advantages and avoid the destruction of the crystal structure of conductive materials—conductive carbon materials and perovskite (such as the graphitized structure of conductive carbon materials and the BO6 octahedral structure of perovskite) due to the chemical environment. This maintains stable conductivity and provides a reliable current path for electrothermal conversion.

[0071] In some embodiments, the above-mentioned composite method is a single hydrothermal treatment (in-situ growth). This single hydrothermal treatment involves mixing conductive materials—conductive carbon materials and perovskite—with molecular sieve precursors, and then directly generating molecular sieves on the surface / within the pores of the perovskite or conductive carbon materials through chemical reactions such as pyrolysis and hydrothermal synthesis, thereby forming a composite molecular sieve catalyst. The composite molecular sieve catalyst synthesized through this single hydrothermal treatment method allows the perovskite or conductive carbon materials to form chemical bonds with the molecular sieves through coordination bonds and covalent bonds. This results in high bonding strength, preventing material detachment and agglomeration during electric heating cycles or reaction fluid scouring, ensuring long-term operational stability, and meeting the high requirements of industrial applications for catalyst comprehensive performance.

[0072] For example, the ultrasonic dispersion time can be 0.5 h, 1 h, or 2 h, preferably 1 h.

[0073] For example, after the above-mentioned ultrasound is completed, stirring is continued for 1 h, 2 h, 3 h, 4 h, 5 h, or 6 h, preferably 2 h.

[0074] The secondary hydrothermal treatment in the above preparation method can make the components of the composite molecular sieve catalyst prepared by the composite step more tightly bound, and make the final composite molecular sieve catalyst product more robust. At the same time, after the above secondary hydrothermal treatment, the conductive carbon material and perovskite distributed around the molecular sieve are more uniform, thus making the conductivity of the composite molecular sieve catalyst more stable.

[0075] For example, the temperature of the above-mentioned secondary hydrothermal treatment is 120 ℃, 140 ℃, 160 ℃, 180 ℃, 200 ℃, or 220 ℃, preferably 200 ℃.

[0076] For example, the duration of the secondary hydrothermal treatment is 6 h, 8 h, 10 h, 12 h, 14 h, 16 h, 18 h, or 20 h, preferably 10 h.

[0077] In some embodiments, perovskite is prepared by a method comprising the following process: subjecting a mixed system comprising a solvent, a metal source, citric acid and a polyol to a secondary sintering process to obtain perovskite; the metal source comprising metal A and metal B; the molar ratio of the metal source, citric acid and polyol being 2 : (1~2) : (2~6);

[0078] Preferably, the secondary sintering treatment specifically includes the following process: heating from room temperature to 200-300 ℃ at a heating rate of 1-10 ℃ / min, holding at that temperature for 1-2 h, then heating to 600-800 ℃, and holding at that temperature for 2-4 h.

[0079] For example, the polyol is one of ethylene glycol, 1,3-propanediol, 1,2-propanediol, and glycerol.

[0080] For example, the temperatures of the three sintering processes are 400 ℃, 500 ℃, and 600 ℃, with 500 ℃ being preferred.

[0081] For example, the sintering times for the three sintering processes can be 1 h, 2 h, 3 h, 4 h, 5 h, or 6 h, with 2 h being preferred.

[0082] In a preferred embodiment, the perovskite preparation process, after obtaining the mixed system including solvent, metal source, citric acid and polyol, and before the secondary sintering treatment, further includes stirring to form a complex and drying at a temperature of 100~120 °C.

[0083] For example, the drying temperature is 100 ℃, 110 ℃, or 120 ℃, preferably 110 ℃.

[0084] In some embodiments, the perovskite obtained by the above preparation method has the chemical formula ABO3, where A is provided by metal source A and B is provided by metal source B. Metal source A is at least one of La(NO3)3, Ba(NO3)2, Nd(NO3)3, and Y(NO3)3, and metal source B is at least one of Cu(NO3)2, Co(NO3)2, Ni(NO3)2, Fe(NO3)3, Zn(NO3)2, and Mn(NO3)2. The molar ratio of metal cations of metal source A to metal source B is 1:1.

[0085] In a preferred embodiment, in the above preparation method, a secondary sintering treatment is performed by slowly heating the material to 200-300 °C at a rate of 1-10 °C / min, holding it at that temperature for 1-2 h, and then heating it to 600-800 °C for a third holding period of 2-4 h. This reduces particle cracking or sintering caused by thermal stress, ensures uniform perovskite particle size, and prevents agglomeration that could block the pores of the conductive carbon material and the molecular sieve. This improves the conductivity and catalytic activity of the composite molecular sieve catalyst.

[0086] In a preferred embodiment, the metal source for the secondary sintering is a metal cation, and the molar ratio of metal cation:citric acid:ethylene glycol is 2:1:4.

[0087] For example, the above-mentioned secondary sintering is carried out by raising the temperature from room temperature to 200 ℃, 250 ℃, or 300 ℃, preferably 200 ℃.

[0088] Thirdly, the present invention provides a catalytic reaction apparatus 1, which includes a power source 10, an insulated reactor 21, and a catalytic bed 22, wherein the catalytic bed 22 is placed inside the insulated reactor 21; the catalytic bed 22 includes a composite molecular sieve catalyst as described in the first aspect.

[0089] In a preferred embodiment, such as Figure 1 As shown, the catalytic reaction device 1 includes a power supply 10 and a reaction vessel 20. The power supply 10 includes a positive electrode and a negative electrode, which are connected to the reaction vessel 20 to supply power to the reaction vessel 20.

[0090] The reaction vessel 20 includes an insulated reactor 21, a catalyst bed 22, electrode plates 23, and an inlet / outlet A. The inlet / outlet A is located on the reaction vessel 20 and connects to the inner cavity of the insulated reactor 21, allowing the reactants to enter the inner cavity of the insulated reactor 21. In this invention, a composite molecular sieve catalyst is disposed within the inner cavity of the insulated reactor 21, allowing contact with the reactants, and a catalyst bed 22 is formed at the location of the composite molecular sieve catalyst. The catalyst bed 22 is connected to the electrode plates 23.

[0091] The insulating reactor 21 is made of an insulating material, which may be, for example, quartz.

[0092] The composite molecular sieve catalyst on the catalyst bed 22 is connected to the power source 10 through the electrode plate 23. Specifically, the composite molecular sieve catalyst prepared in this invention is filled into the inner cavity of the insulating reactor 21, and the positive and negative electrodes of the power source 10 are connected to the electrode plate 23 respectively. The electrode plate 23 is connected to the composite molecular sieve catalyst. A complete conductive circuit of "power source-electrode plate-composite molecular sieve catalyst" is constructed through direct contact or indirect contact through a conductive medium to ensure that the current can be stably transmitted to the composite molecular sieve catalyst of this invention after power is applied.

[0093] In some embodiments, the catalytic reaction device 1 includes a raw material tank, a raw material pump, a preheating furnace, a heat preservation device, a catalytic bed 22, a quartz reaction tube, an electrode 23, and a DC power supply.

[0094] After being energized, the composite molecular sieve catalyst converts electrical energy into Joule heat through electrothermal conversion, providing the necessary heat energy for the reaction and satisfying the electrothermal conversion required for driving the catalytic reaction with electrical power. On the other hand, it participates in the electron transfer process as an electrocatalytic active support, assisting the target catalytic reaction to proceed efficiently.

[0095] To further understand the present invention, the technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0096] Unless otherwise specified, all reagents involved in the embodiments of this invention are commercially available products and can be purchased through commercial channels.

[0097] Example 1

[0098] The preparation of a composite molecular sieve catalyst includes the following steps:

[0099] (1) Ordered mesoporous carbon CMK-3 was added to a solution of HNO3 with a mass fraction of 15 wt.%, and the suspension was stirred in a water bath at 80°C for 3 h. Then it was rinsed with deionized water several times until neutral and placed in an oven to dry at 110°C for 4 h. The dried carbon material was subjected to a sintering treatment under a nitrogen atmosphere, that is, under a nitrogen flow rate of 25 mL / min, the temperature was raised to 700°C at a heating rate of 2°C / min and held for 4 h. Then it was cooled to room temperature to obtain conductive carbon material.

[0100] (2) A metal source (La(NO3)3 and Cu(NO3)2 in a molar ratio of 1:1) was dissolved in deionized water with citric acid and ethylene glycol in a molar ratio of metal cation:citric acid:ethylene glycol of 2:1:4 to produce a homogeneous solution. The solution was stirred overnight at room temperature and then microwaved at 80 °C for 1 h to form a complex. The water was then evaporated in an oil bath at 90 °C. After forming a gel, the mixture was transferred to a drying oven and dried at 110 °C. The dried gel was calcined at 200 °C at a heating rate of 5 °C / min, and held at this temperature for 2 h. Then the temperature was increased to 700 °C and calcined for 4 h at a heating rate of 5 °C / min to obtain perovskite LaCuO3.

[0101] (3) The ZSM-5 molecular sieve and the conductive carbon material obtained in step (1) are combined in a mass ratio of 1:3 to obtain a composite material. Then, the above composite material and LaCuO3 are weighed in a mass ratio of 1:1. The conductive carbon material obtained in step (1), the perovskite obtained in step (2) and the ZSM-5 molecular sieve are placed in deionized water in a mass ratio of 3:4:1 and ultrasonically dispersed for 1 h. After ultrasonic dispersion, the mixture is stirred for another 2 h. The solution is then transferred into the lining of a 100 mL hydrothermal reactor. The reactor is then placed in a vacuum drying oven at 200 °C and hydrothermally reacted for 10 h. After cooling to room temperature, the product is washed and filtered multiple times with deionized water and anhydrous ethanol. It is then dried overnight in an oven at 80 °C. After grinding, the product is transferred to a crucible and placed in a muffle furnace. It is then calcined in an air atmosphere at 500 °C for 2 h to finally obtain the composite molecular sieve catalyst.

[0102] Example 2

[0103] It is basically the same as Example 1, except that the mass ratio of the conductive carbon material obtained in step (1), the perovskite obtained in step (2), and the ZSM-5 molecular sieve is 1:4:1.

[0104] Example 3

[0105] It is basically the same as Example 1, except that the mass ratio of the conductive carbon material obtained in step (1), the perovskite obtained in step (2), and the ZSM-5 molecular sieve is 6:4:1.

[0106] Example 4

[0107] It is basically the same as Example 1, except that the mass ratio of the conductive carbon material obtained in step (1), the perovskite obtained in step (2), and the ZSM-5 molecular sieve is 1:10:1.

[0108] Example 5

[0109] It is basically the same as Example 1, except that the mass ratio of the conductive carbon material obtained in step (1), the perovskite obtained in step (2), and the ZSM-5 molecular sieve is 6:10:1.

[0110] Example 6

[0111] It is basically the same as Example 1, except that in step (1), graphite is added to a solution of HNO3 with a mass fraction of 15 wt.%.

[0112] Example 7

[0113] It is basically the same as Example 1, except that the mass ratio of the conductive carbon material obtained in step (1) to the perovskite and SAPO molecular sieve obtained in step (2) is 3:4:1.

[0114] Example 8

[0115] The results are basically the same as in Example 1, except that the metal sources are La(NO3)3 and Co(NO3)2 in a molar ratio of 1:1, resulting in a perovskite with the chemical formula LaCoO3.

[0116] Example 9

[0117] The results are basically the same as in Example 1, except that the metal sources are La(NO3)3 and Fe(NO3)2 in a molar ratio of 1:1, resulting in a perovskite with the chemical formula LaFeO3.

[0118] Table 1:

[0119]

[0120] Experimental Example 1

[0121] The composite molecular sieve catalyst obtained in Example 1 was placed in a... Figure 1 In the catalytic reaction apparatus shown, the catalytic bed is heated to 450 °C by electric power supply, and then 1-hexene and H2O are mixed and fed to carry out the catalytic cracking reaction of 1-hexene to produce low carbon olefins.

[0122] Table 2:

[0123]

[0124] Infrared thermography images of the catalytic cracking unit in progress are shown in the attached image. Figure 2 Infrared thermal imaging of the catalytic reaction apparatus shown. Figure 2 As shown, the composite molecular sieve catalyst provided in Example 1, when applied to the electrically powered heating reaction device described above, can ensure uniform heating of the catalytic cracking reaction and improve catalytic performance.

[0125] Experimental Example 2

[0126] The results were basically the same as in Experiment 1, except that the catalyst bed was heated to 500 °C using an electric power source, as shown in Table 2.

[0127] Experimental Example 3

[0128] It is basically the same as Experiment 1, except that the catalyst bed is heated to 550 °C by electric power supply, as shown in Table 2.

[0129] Test Example 4

[0130] The composite molecular sieve catalyst obtained in Example 9 was placed in a... Figure 1 In the catalytic reaction apparatus shown, the catalytic bed is heated to 550 °C by electric power supply, and then 1-hexene and H2O are mixed and fed to carry out the catalytic cracking reaction of 1-hexene to produce low carbon olefins.

[0131] Experimental Example 5

[0132] It is basically the same as Experimental Example 1, except that the catalyst bed is heated by external heating.

[0133] Experimental Example 6

[0134] It is basically the same as Experimental Example 2, except that the catalyst bed is heated by external heating.

[0135] Experimental Example 7

[0136] It is basically the same as Experimental Example 3, except that the catalyst bed is heated by external heating.

[0137] Experimental Example 8

[0138] The composite molecular sieve catalyst obtained in Example 6 was placed in a... Figure 1 In the catalytic reaction apparatus shown, the catalytic bed is heated to 550 °C by electric power supply, and then 1-hexene and H2O are mixed and fed to carry out the catalytic cracking reaction of 1-hexene to produce low carbon olefins.

[0139] Comparative Example 1

[0140] ZSM-5 molecular sieve with a silicon-to-aluminum ratio of 25 was pressed into tablets and sieved to obtain molecular sieve particles of 40-60 mesh. Without combining with other materials, the obtained molecular sieve catalyst was placed in the catalytic reaction device provided by the present invention. The catalytic bed was heated to 550 °C by external heating. Then, 1-hexene and H2O were mixed and fed to carry out the catalytic cracking reaction of 1-hexene to produce low-carbon olefins, as shown in Table 2.

[0141] Comparative Example 2

[0142] It is basically the same as Comparative Example 1, except that the catalyst bed is heated to 500 °C, as shown in Table 2.

[0143] Comparative Example 3

[0144] It is basically the same as Comparative Example 1, except that the catalyst bed is heated to 450 °C, as shown in Table 2.

[0145] Comparative Example 4

[0146] The preparation of a composite molecular sieve catalyst includes the following steps:

[0147] (1) A metal source (La(NO3)3 and Cu(NO3)2 in a molar ratio of 1:1) was dissolved in deionized water with citric acid and ethylene glycol in a molar ratio of metal cation:citric acid:ethylene glycol of 2:1:4 to produce a homogeneous solution. The solution was stirred overnight at room temperature and then microwaved at 80 °C for 1 h to form a complex. The water was then evaporated in an oil bath at 90 °C. After forming a gel, the mixture was transferred to a drying oven and dried at 110 °C. The dried gel was calcined at 200 °C at a heating rate of 5 °C / min, and held at this temperature for 1-2 h. Then the temperature was raised to 700 °C and calcined for 2-4 h, with a heating rate of 5 °C / min, to obtain perovskite LaCuO3.

[0148] (2) ZSM-5 molecular sieve and ordered mesoporous carbon CMK-3 were composited in a mass ratio of 1:3. Then, the above composite material and LaCuO3 were weighed in a mass ratio of 1:1. The ordered mesoporous carbon CMK-3, the perovskite obtained in step (1) and ZSM-5 molecular sieve were placed in deionized water in a mass ratio of 3:4:1 and ultrasonically dispersed for 1 h. After ultrasonication, the mixture was stirred for another 2 h. The solution was then transferred into the lining of a 100 mL hydrothermal reactor. The reactor was then placed in a vacuum drying oven at 200 °C and hydrothermally reacted for 10 h. After cooling to room temperature, the product was washed and filtered multiple times with deionized water and anhydrous ethanol. It was then dried overnight in an oven at 80 °C. After grinding, the product was transferred to a crucible and placed in a muffle furnace. It was calcined in an air atmosphere at 500 °C for 2 h to finally obtain a composite molecular sieve catalyst without connecting functional groups.

[0149] The catalyst is placed in such Figure 1 In the catalytic reaction apparatus shown, the catalytic bed is heated to 550 °C by electric power supply. Then, 1-hexene and H2O are mixed and fed to carry out the catalytic cracking reaction of 1-hexene to produce low-carbon olefins, as shown in Table 2.

[0150] Test Example 1

[0151] The conductivity of the composite molecular sieve catalysts provided in Examples 1-9 was tested, and the results are shown in Table 1. It can be seen that the composite molecular sieve catalysts provided in Examples 1-9 have higher conductivity, and therefore better electrothermal conversion efficiency. Therefore, the composite molecular sieve catalyst of the present invention can convert the introduced electrical energy into Joule heat, realizing a catalytic reaction system that relies solely on electric heating, while possessing both high conductivity and catalytic performance.

[0152] The catalytic cracking performance of the catalysts provided in Examples 1, 6, 9, and Comparative Examples 1-4 was tested, and the test results are shown in Table 2. Under the same heating conditions, the conversion rate of the catalytic reaction using the composite molecular sieve catalyst provided in this application is higher than that using the composite molecular sieve catalyst with ZSM-5 molecular sieve and no connecting functional groups, resulting in a higher yield. Therefore, compared with the comparative examples, the composite molecular sieve catalyst of the present invention has good catalytic activity.

[0153] Furthermore, the results of Experiments 1-3 and 5-7 show that, at the same heating temperature, when using the composite molecular sieve catalyst prepared in Example 1, the catalytic cracking reaction performed by the electric heating method provided by this invention has significantly better results compared to external heating. This is because electric heating allows Joule heating to be generated in situ through the conductivity of the catalyst, eliminating the heat loss associated with external heating and resulting in higher energy utilization. Simultaneously, the presence of an external electric field can activate the reactants, promote the formation of reaction intermediates, improve reaction efficiency, and significantly reduce the occurrence of side reactions that occur with external heating.

[0154] Meanwhile, by comparing various performance parameters, the preparation method of the composite molecular sieve catalyst provided in this application embodiment can produce composite molecular sieve catalysts with better performance.

[0155] Test Example 2

[0156] X-ray diffraction analysis was performed on the perovskite LaCuO3 obtained in Example 1, the perovskite LaCoO3 obtained in Example 8, and the ordered mesoporous carbon CMK-3 obtained in Example 1. For specific test results, please refer to [link to relevant documentation]. Figure 3 .

[0157] like Figure 3 As shown, the perovskite LaCuO3 obtained in Example 1 and the perovskite LaCoO3 obtained in Example 8 both have typical diffraction peaks of perovskite; the ordered mesoporous carbon CMK-3 obtained in Example 1 has typical diffraction peaks of CMK-3.

[0158] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A composite molecular sieve catalyst, characterized in that, The invention comprises a molecular sieve and a perovskite and conductive carbon material supported on at least a portion of the surface of the molecular sieve, wherein the surface of the conductive carbon material includes connecting functional groups; at least a portion of the connecting functional groups are connected to the molecular sieve.

2. The composite molecular sieve catalyst according to claim 1, characterized in that, The mass ratio of the conductive carbon material, perovskite, and molecular sieve is (1~6):(4~10):

1.

3. The composite molecular sieve catalyst according to claim 1 or 2, characterized in that, The connecting functional group includes at least one of the following: amino, imino, amide, cyano, nitro, pyridyl, nitroso, hydroxyl, carboxyl, and epoxy.

4. The composite molecular sieve catalyst according to any one of claims 1-3, characterized in that, The conductive carbon material comprises at least one of ordered mesoporous carbon, graphite, activated carbon, carbon nanotubes, graphene, and carbon aerogel.

5. The composite molecular sieve catalyst according to any one of claims 1-4, characterized in that, The chemical formula of the perovskite is ABO3, wherein A includes La. 3+ Ba 2+ 、Nd 3+ Y 3+ At least one of them, B includes Cu 2+ Co 2+ Ni 2+ Fe 3+ Zn 2+ Mn 2+ At least one of them.

6. The composite molecular sieve catalyst according to any one of claims 1-5, characterized in that, The molecular sieve includes at least one of ZSM molecular sieve, Beta molecular sieve, SAPO molecular sieve, MOR molecular sieve, and Y-type molecular sieve.

7. A method for preparing the composite molecular sieve catalyst according to any one of claims 1-6, characterized in that, Includes the following steps: The carbon source is etched using acid, followed by a sintering process to obtain a conductive carbon material with the aforementioned connecting functional groups on its surface. The composite molecular sieve catalyst is obtained by combining the perovskite, the conductive carbon material with interconnected functional groups on its surface, and the molecular sieve.

8. The preparation method according to claim 7, characterized in that, The first sintering process specifically includes the following steps: under a nitrogen flow rate of 5-30 mL / min, the temperature is raised to 400-900 ℃ at a heating rate of 1-5 ℃ / min, and held for 2-6 h. The composite method includes mechanical mixing or a single hydrothermal treatment; The composite process further includes a secondary hydrothermal treatment and a tertiary sintering treatment; wherein the secondary hydrothermal treatment is performed at a temperature of 120~220 ℃ for a time of 6~20 h; the tertiary sintering treatment includes sintering at 400~600 ℃ for 1~6 h.

9. The preparation method according to claim 7 or 8, characterized in that, The perovskite is prepared by a method comprising the following process: a mixed system comprising a solvent, a metal source, citric acid and a polyol is subjected to a secondary sintering treatment to obtain the perovskite; the metal source comprises metal A and metal B; the molar ratio of the metal source, citric acid and polyol is 2 : (1~2) : (2~6); Preferably, the secondary sintering treatment specifically includes the following process: heating from room temperature to 200-300 ℃ at a heating rate of 1-10 ℃ / min, holding at that temperature for 1-2 h, then heating to 600-800 ℃, and holding at that temperature for 2-4 h.

10. A catalytic reaction apparatus, characterized in that, The catalytic reaction device includes a power source, an insulated reactor, and a catalytic bed, wherein the catalytic bed is placed inside the insulated reactor; the catalytic bed contains a composite molecular sieve catalyst as described in any one of claims 1-6.

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