Catalyst for preparing C4 hydrocarbon from synthesis gas as well as preparation method and application of catalyst

Abstract

The invention discloses a catalyst for preparing C4 hydrocarbon from synthesis gas and a preparation method of the catalyst, and relates to the field of heterogeneous catalysis. The catalyst provided by the invention comprises an active component, a first metal additive, a second metal additive and a carrier, wherein the active component exists in a pore channel and on the outer surface of the carrier in a cluster form. The invention also provides at least three preparation methods of the catalyst, and provides application and application conditions of the catalyst in preparation of C4 hydrocarbon from synthesis gas. The catalyst is prepared through an in-situ packaging synthesis method, the carrier in the catalyst has a specific pore channel structure easy to diffuse and shape-selective catalytic characteristics, composite metal oxide clusters can be effectively limited, migration and agglomeration of the composite metal oxide clusters can be inhibited, and the selectivity of the packaging structure catalyst to low-carbon hydrocarbons, especially C4 hydrocarbons is improved; in addition, the stability of the packaging structure catalyst at high temperature can be improved, and the packaging structure catalyst has important industrial application potential.

Description

Technical Field

[0001] The present invention belongs to the technical field of heterogeneous catalysis, and in particular relates to a catalyst for preparing C4 hydrocarbons from synthesis gas, and a preparation method and application thereof. Background Art

[0002] C4 hydrocarbons (butane, isobutane, butylene, isobutylene, etc.) are important bulk chemicals with a wide range of applications. They can be used not only as fuel, but also in the synthesis of plastics, rubber, resins, medicines, pesticides, and additives. However, their sources are heavily dependent on petroleum resources, and their output is difficult to meet the growing market demand. For some countries or regions, coal resources are more abundant than oil. Synthesis gas is obtained by coal gasification, and then considerable hydrocarbon products can be obtained through Fischer-Tropsch synthesis or directional coupling catalysis.

[0003] The product distribution of Fischer-Tropsch synthesis is limited by the ASF carbon number distribution law, and it is difficult for C2-C4 hydrocarbon products to exceed 60%, as reported in patents CN105709772A, CN103657674A, etc. In order to further improve the selectivity of low-carbon hydrocarbons, the selectivity of low-carbon hydrocarbons can be effectively improved to 80-90% by constructing methanol-related intermediates through bifunctional coupling catalysts (OX-ZEO) (CN109701632A, CN102219628A, etc.). However, it is very challenging to achieve high selectivity for specific C4 hydrocarbons through CO hydrogenation. The selectivity for C4 hydrocarbons in the catalytic synthesis gas products reported so far is usually very low, mostly less than 30%.

[0004] For CO hydrogenation over the bifunctional OX-ZEO catalyst, first, the oxide part can construct a methanol intermediate, and then the intermediate is further converted into hydrocarbons on the acidic sites of the zeolite. In2O3 is an efficient catalyst for CO hydrogenation to methanol. Usually, in order to suppress the formation of CH4 and CO, various dopants are needed to adjust the crystal structure and surface electronic properties of In2O3. In addition, in order to obtain higher alkanes / olefins such as butane, the required molecular sieves need not only to have acidic sites, but also to have relatively large pore channels, so that they can accommodate the generation and rapid diffusion of larger reaction intermediates.

[0005] In addition, it is noted in the literature (Angew. Chem. Int. Ed. 2021 (60), 17735–17743) that the In2O3 active component is easily lost on conventional supports and causes rapid poisoning of the acidic sites on the catalyst.

[0006] In view of this, this application is hereby filed. Summary of the invention

[0007] The purpose of the present invention is to provide a catalyst for preparing C4 hydrocarbons from synthesis gas, and a preparation method and application thereof. The catalyst is prepared by an in-situ encapsulation synthesis method. The carrier in the catalyst has a specific, easily diffusible pore structure and shape-selective catalytic properties, which can effectively confine composite metal oxide clusters, inhibit their migration and agglomeration, and improve the selectivity of the encapsulated structure catalyst to low-carbon hydrocarbons, especially C4 hydrocarbons; in addition, it can also improve the stability of the encapsulated structure catalyst at high temperature, and has important industrial application potential.

[0008] In the first aspect, the present application provides a catalyst for preparing C4 hydrocarbons from synthesis gas, comprising an active component, a first metal additive, a second metal additive and a carrier; the active component, the first metal additive and the second metal additive exist in the form of clusters inside the pores and on the outer surface of the carrier.

[0009] In a second aspect, the present application provides a method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas, comprising the following steps:

[0010] (1) mixing a molecular sieve template, a silicon source, an aluminum source, potassium chloride and water in a mass ratio of (0.1-3.0):(15-50):(1-10):(0.5-5.0):100 in a hydrothermal reactor and stirring to obtain a carrier precursor;

[0011] (2) adding a water-soluble active component precursor, an encapsulation promoter, a water-soluble precursor of the first metal promoter and a water-soluble precursor of the second metal promoter to the hydrothermal kettle according to the mass ratio of the active component: encapsulation promoter: first metal promoter: second metal promoter: carrier precursor being (0.5-2.0):(0.5-2.0):(0.5-2.0):(0.2-1.0):100, heat treating, centrifuging, washing and drying to obtain a solid powder; wherein the mass of the active component is measured by the amount of the active metal element;

[0012] (3) calcining the solid powder to obtain the MFI molecular sieve encapsulated cluster catalyst;

[0013] (4) Immersing an equal volume of the MFI molecular sieve encapsulated cluster catalyst in an ammonium chloride solution, performing ion exchange, filtering, washing, drying, and calcining to obtain a MFI molecular sieve encapsulated cluster catalyst containing B acid.

[0014] In a third aspect, the present application provides another method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas, comprising the following steps:

[0015] (1) mixing a silicon source, an aluminum source, sodium hydroxide and water in a mass ratio of (5-10):(2-10):(0.5-2.0):100 in a hydrothermal reactor, stirring and aging to prepare a structure directing agent;

[0016] (2) according to the mass ratio of the active component: encapsulation promoter: first metal auxiliary agent: second metal auxiliary agent: structure directing agent being (0.5-2.0):(0.5-2.0):(0.5-2.0):(0.2-1.0):100, a water-soluble active component precursor, an encapsulation promoter, a water-soluble precursor of the first metal auxiliary agent and a water-soluble precursor of the second metal auxiliary agent are added to the hydrothermal kettle, and at the same time, a silicon source, an aluminum source and sodium hydroxide are added in the same proportion as step (1) but 5-10 times the amount of step (1), heat treatment, centrifugation, washing and drying are performed to obtain a solid powder; wherein the mass of the active component is measured by the amount of the active metal element;

[0017] (3) calcining the solid powder to obtain the FAU molecular sieve encapsulated nanocluster catalyst;

[0018] (4) Immersing an equal volume of the FAU molecular sieve encapsulated nanocluster catalyst in an ammonium chloride solution, performing ion exchange, filtering, washing, drying, and calcining to obtain a FAU molecular sieve encapsulated cluster catalyst containing B acid.

[0019] In a fourth aspect, the present application provides another method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas, comprising the following steps:

[0020] (1) mixing a silicon source, an aluminum source, a template and water in a mass ratio of (15-50):(1-10):(0.1-3.0):100 in a hydrothermal reactor and stirring to obtain a carrier precursor;

[0021] (2) adding a water-soluble active component precursor, an encapsulation promoter, a water-soluble precursor of the first metal promoter and a water-soluble precursor of the second metal promoter to the hydrothermal kettle according to the mass ratio of the active component: encapsulation promoter: first metal promoter: second metal promoter: carrier precursor being (0.5-2.0):(0.5-2.0):(0.5-2.0):(0.2-1.0):100, heat treating, centrifuging, washing and drying to obtain a solid powder; wherein the mass of the active component is measured by the amount of the active metal element;

[0022] (3) calcining the solid powder to obtain a Beta molecular sieve encapsulated nanocluster catalyst;

[0023] (4) Immersing an equal volume of the Beta molecular sieve encapsulated nanocluster catalyst in an ammonium chloride solution, performing ion exchange, filtering, washing, drying, and calcining to obtain a BEA* molecular sieve encapsulated cluster catalyst containing B acid.

[0024] In a fifth aspect, the present application provides an application of the catalyst in the reaction of preparing C4 hydrocarbons from synthesis gas, wherein the application conditions are:

[0025] The volume ratio of CO and H2 in the synthesis gas is 1:(1-5), the catalytic reaction temperature is 280-350℃, the catalytic reaction pressure is 2.5-6MPa, and the synthesis gas volume space velocity is 1000-3000h -1 .

[0026] The catalyst for preparing C4 hydrocarbons from synthesis gas provided in the present application, and its preparation method and application have the following beneficial effects:

[0027] 1. The present application utilizes molecular sieves to encapsulate metal active components and metal additives, and can utilize the molecular sieve microchannels to limit the size of composite metal oxide clusters, thereby reducing the size of the clusters, significantly increasing the active centers on the active components, and improving the catalytic activity of the catalyst.

[0028] 2. The present application utilizes the first metal additive and the second metal additive to adjust the dispersibility and electronic effect of the active component, which can further improve the catalytic performance of the active component of the catalyst, reduce the amount of the active component, and reduce the catalyst cost for industrialization. In addition, the high dispersibility of the structural additive can improve the stability of the active component of the catalyst, laying the foundation for industrial fixed bed continuous reaction.

[0029] 3. The silicon-aluminum ratio design of the molecular sieve carrier increases the proportion of alumina, the acid content and acid sites of the carrier, and can significantly increase the selectivity of low-carbon hydrocarbon products, especially the selectivity of C4 hydrocarbons, which can be as high as 49%.

[0030] 4. The present application provides a technology for encapsulating precious metal active components in molecular sieves and its expanded applications. The preparation method has the characteristics of strong operability, good economy, and stable quality.

[0031] 5. The catalyst provided in this application can be repeatedly recycled and regenerated, is very suitable for industrial production, and has high industrial value.

[0032] In summary, the present application performs bifunctional coupling by doping and modifying the In2O3 active component while preferably using a molecular sieve with strong acidity and a larger pore channel topology. The resulting catalyst can provide a high yield of C4 hydrocarbons for CO hydrogenation. At the same time, the present application uses the in-situ synthesis method of molecular sieves to encapsulate the active components and their doped and modified components, and confines the composite metal oxide clusters through the micropores and skeleton gaps of the molecular sieves, so that they can be effectively anchored, inhibiting their migration and loss, and significantly improving the catalytic stability of the OX-ZEO catalyst in CO hydrogenation. This design provides an important direction for the development of stable In-based catalysts in the process of exploring the preparation of specific hydrocarbon products by CO hydrogenation. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope of the present application.

[0034] Figure 1 This is the XRD pattern of the catalyst obtained in Example 1 of the present invention.

[0035] Figure 2 This is the XRD pattern of the catalyst obtained in Example 3 of the present invention. DETAILED DESCRIPTION

[0036] The embodiments of the present invention will be described in detail below in conjunction with specific examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present invention and should not be considered to limit the scope of the present invention. If specific conditions are not specified in the examples, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0037] In the present invention, the term "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0038] It should be noted that if there is a mixture in the following examples or comparative examples, and if the ratio relationship is not specified, the components can be in any ratio.

[0039] The present application discloses a catalyst for preparing C4 hydrocarbons from synthesis gas, which comprises an active component, a first metal additive, a second metal additive and a carrier; the active component, the first metal additive and the second metal additive exist in the form of clusters inside the pores and on the outer surface of the carrier.

[0040] In some embodiments, the active component includes In.

[0041] In some embodiments, the first metal promoter includes Zr.

[0042] In some embodiments, the second metal promoter includes Zn and / or Ga.

[0043] In some embodiments, the support comprises a molecular sieve support.

[0044] In some preferred embodiments, the carrier includes one or more of a ZSM-5 molecular sieve having an MFI topology, a Y molecular sieve having an FAU topology, or a Beta molecular sieve having a BEA* topology.

[0045] A method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas according to the present application comprises the following steps:

[0046] (1) A molecular sieve template, a silicon source, an aluminum source, potassium chloride and water in a mass ratio of (0.1-3.0):(15-50):(1-10):(0.5-5.0):100 are mixed in a hydrothermal kettle and stirred to obtain a carrier precursor; wherein the molecular sieve template, silicon source, aluminum source and potassium chloride are calculated by metal mass (ammonium is regarded as metal).

[0047] In some embodiments, the molecular sieve template agent includes one or more of tetrapropylammonium hydroxide, tetraethylammonium hydroxide or tetrabutylammonium hydroxide.

[0048] The silicon source is one or more of tetramethyl orthosilicate, tetraethyl orthosilicate, butyl orthosilicate or sodium silicate, etc.; the aluminum source is one or more of pseudo-boehmite, aluminum nitrate or sodium aluminate, etc.

[0049] In some embodiments, the stirring temperature is 30-50° C., and the stirring time is 6-24 h.

[0050] (2) According to the mass ratio of the active component: encapsulation promoter: first metal auxiliary agent: second metal auxiliary agent: carrier precursor being (0.5-2.0):(0.5-2.0):(0.5-2.0):(0.2-1.0):100, a water-soluble active component precursor, an encapsulation promoter, a water-soluble precursor of the first metal auxiliary agent and a water-soluble precursor of the second metal auxiliary agent are added to the hydrothermal kettle, heat treated, centrifuged, washed, and dried to obtain a solid powder. The mass of the active component is measured by the amount of the active metal element.

[0051] In some optional embodiments, the encapsulation promoter includes one or more of ethylenediamine, 1,3-butanediamine or 1,4-butanediamine.

[0052] In some optional embodiments, the water-soluble active component precursor includes indium nitrate and / or indium chloride.

[0053] In some optional embodiments, the water-soluble precursor of the first metal additive includes zirconium nitrate and / or zirconium chloride.

[0054] In some optional embodiments, the water-soluble precursor of the second metal additive includes one or more of zinc chloride, zinc nitrate, gallium nitrate or gallium chloride.

[0055] In some embodiments, the heat treatment is performed at 100-200° C. for 12-96 h.

[0056] (3) calcining the solid powder to obtain the MFI molecular sieve encapsulated cluster catalyst;

[0057] (4) Immersing an equal volume of the MFI molecular sieve encapsulated cluster catalyst in an ammonium chloride solution, performing ion exchange, filtering, washing, drying, and calcining to obtain a MFI molecular sieve encapsulated cluster catalyst containing B acid.

[0058] In some embodiments, the concentration of the ammonium chloride solution is 1.0-3.0 mol / L.

[0059] In some embodiments, the ion exchange temperature is 60-100° C., and the ion exchange time is 24-96 h.

[0060] In some embodiments, in step (3) and step (4), the calcination temperature is 500-650° C., and the calcination time is 5-15 h.

[0061] Another method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas in the present application comprises the following steps:

[0062] (1)(1) A silicon source, an aluminum source, sodium hydroxide and water in a mass ratio of (5-10):(2-10):(0.5-2.0):100 are mixed in a hydrothermal kettle, stirred and aged to prepare a structure directing agent; wherein the silicon source, the aluminum source and the sodium hydroxide are calculated by metal mass.

[0063] In some embodiments, the stirring temperature is 25-50° C., and the stirring time is 2-10 h.

[0064] (2) according to the mass ratio of the active component: encapsulation promoter: first metal auxiliary agent: second metal auxiliary agent: structure directing agent being (0.5-2.0):(0.5-2.0):(0.5-2.0):(0.2-1.0):100, a water-soluble active component precursor, an encapsulation promoter, a water-soluble precursor of the first metal auxiliary agent and a water-soluble precursor of the second metal auxiliary agent are added to the hydrothermal kettle, and at the same time, a silicon source, an aluminum source and sodium hydroxide are added in the same proportion as in step (1) but 5-10 times the amount of step (1), heat treatment, centrifugation, washing and drying are performed to obtain a solid powder; wherein the mass of the active component is measured by the amount of the active metal element.

[0065] In step (1), a small amount of silicon source, aluminum source and sodium hydroxide are added to prepare a small amount of structure directing agent, similar to seed crystals; in step (2), a large amount of silicon source and aluminum source are added to synthesize a large amount of Y molecular sieve (FAU) using the seed crystals as templates.

[0066] The silicon source is one or more of tetramethyl orthosilicate, tetraethyl orthosilicate, butyl orthosilicate or sodium silicate, etc.; the aluminum source is one or more of pseudo-boehmite, aluminum nitrate or sodium aluminate, etc.

[0067] In some embodiments, the encapsulation promoter includes one or more of ethylenediamine, 1,3-butanediamine, or 1,4-butanediamine.

[0068] In some embodiments, the water-soluble active component precursor includes indium nitrate and / or indium chloride.

[0069] In some embodiments, the water-soluble precursor of the first metal additive includes zirconium nitrate and / or zirconium chloride.

[0070] In some embodiments, the water-soluble precursor of the second metal additive includes one or more of zinc chloride, zinc nitrate, gallium nitrate or gallium chloride.

[0071] In some embodiments, the heat treatment is performed at 80-150° C. for 12-48 h.

[0072] (3) The solid powder is calcined to obtain the FAU molecular sieve encapsulated nanocluster catalyst.

[0073] (4) Immersing an equal volume of the FAU molecular sieve encapsulated nanocluster catalyst in an ammonium chloride solution, performing ion exchange, filtering, washing, drying, and calcining to obtain a FAU molecular sieve encapsulated cluster catalyst containing B acid.

[0074] In some embodiments, the concentration of the ammonium chloride solution is 1.0-3.0 mol / L.

[0075] In some embodiments, the ion exchange temperature is 60-110° C., and the ion exchange time is 12-96 h.

[0076] In some embodiments, in step (3) and step (4), the calcination temperature is 500-650° C., and the calcination time is 5-15 h.

[0077] Another method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas according to the present application comprises the following steps:

[0078] (1) A silicon source, an aluminum source, a template and water in a mass ratio of (15-50):(1-10):(0.1-3.0):100 are mixed in a hydrothermal kettle and stirred to obtain a carrier precursor; wherein the silicon source, the aluminum source and the template are calculated by metal mass (ammonium is regarded as metal).

[0079] In some embodiments, the templating agent includes tetraethylammonium hydroxide and / or tetraethylammonium bromide.

[0080] The silicon source is one or more of tetramethyl orthosilicate, tetraethyl orthosilicate, butyl orthosilicate or sodium silicate, etc.; the aluminum source is one or more of pseudo-boehmite, aluminum nitrate or sodium aluminate, etc.

[0081] In some embodiments, the stirring temperature is 20-50° C., and the stirring time is 4-24 h.

[0082] (2) adding a water-soluble active component precursor, an encapsulation promoter, a water-soluble precursor of the first metal additive and a water-soluble precursor of the second metal additive to the hydrothermal autoclave according to the mass ratio of the active component: encapsulation promoter: the first metal additive: the second metal additive: the carrier precursor of (0.5-2.0):(0.5-2.0):(0.5-2.0):(0.2-1.0):100, heat treating, centrifuging, washing and drying to obtain a solid powder; wherein the mass of the active component is measured by the amount of the active metal element.

[0083] In some embodiments, the encapsulation promoter includes one or more of ethylenediamine, 1,3-butanediamine, or 1,4-butanediamine.

[0084] In some embodiments, the water-soluble active component precursor includes indium nitrate and / or indium chloride.

[0085] In some embodiments, the water-soluble precursor of the first metal additive includes zirconium nitrate and / or zirconium chloride.

[0086] In some embodiments, the water-soluble precursor of the second metal additive includes one or more of zinc chloride, zinc nitrate, gallium nitrate or gallium chloride.

[0087] In some embodiments, the heat treatment is performed at 110-200° C. for 24-144 h.

[0088] (3) The solid powder is calcined to obtain the Beta molecular sieve encapsulated nanocluster catalyst.

[0089] (4) Immersing an equal volume of the Beta molecular sieve encapsulated nanocluster catalyst in an ammonium chloride solution, performing ion exchange, filtering, washing, drying, and calcining to obtain a BEA* molecular sieve encapsulated cluster catalyst containing B acid.

[0090] In some embodiments, the concentration of the ammonium chloride solution is 1.0-3.0 mol / L;

[0091] In some embodiments, the ion exchange temperature is 60-110° C., and the ion exchange time is 12-96 h;

[0092] In some embodiments, in step (3) and step (4), the calcination temperature is 450-650° C., and the calcination time is 8-24 h.

[0093] The catalyst of the present application is used in the reaction of preparing C4 hydrocarbons from synthesis gas, and its application conditions are:

[0094] The volume ratio of CO and H2 in the synthesis gas is 1:(1-5), the catalytic reaction temperature is 280-350℃, the catalytic reaction pressure is 2.5-6MPa, and the synthesis gas volume space velocity is 1000-3000h -1 .

[0095] Example 1

[0096] A method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas:

[0097] 2.44 g of tetrapropylammonium hydroxide, 8.32 g of tetramethyl orthosilicate, 170 mg of aluminum nitrate, 60 mg of potassium chloride and 14.4 g of water were mixed in a hydrothermal kettle and stirred at 40°C for 12 h; 64.8 mg of indium nitrate, 200 mg of ethylenediamine, 92.4 mg of zirconium nitrate and 72.1 mg of zinc nitrate were added to the hydrothermal kettle, heat treated at 150°C for 48 h, centrifuged, washed, dried at 100°C to obtain a solid powder, and calcined at 550°C for 8 h to obtain an MFI molecular sieve encapsulated cluster catalyst; an equal volume of the solid powder was immersed in a 2.0 mol / L ammonium chloride solution, ion exchanged at 80°C for 48 h, filtered, washed, dried at 100°C, and calcined at 550°C for 8 h to obtain an MFI molecular sieve encapsulated cluster catalyst containing B acid, whose XRD pattern is shown as follows: Figure 1The active component In, the first metal promoter Zr and the second metal promoter Zn in the catalyst exist in the form of clusters inside the pores and on the outer surface of the synthesized MFI molecular sieve carrier.

[0098] The obtained catalyst was used in the reaction of preparing C4 hydrocarbons from synthesis gas. The reaction conditions were: the volume ratio of CO and H2 in the synthesis gas was 1:4, and the synthesis gas volume space velocity was 2000h -1 , the catalytic reaction temperature is 320°C, the catalytic reaction pressure is 4MPa, and the reaction test results are shown in Table 1.

[0099] Example 2

[0100] A method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas:

[0101] 2.44 g of tetrapropylammonium hydroxide, 8.32 g of tetramethyl orthosilicate, 170 mg of aluminum nitrate, 60 mg of potassium chloride and 14.4 g of water are mixed in a hydrothermal kettle and stirred at 40° C. for 12 h; 64.8 mg of indium nitrate, 200 mg of ethylenediamine, 74 mg of zirconium nitrate and 72.5 mg of gallium nitrate are added to the hydrothermal kettle, heat treated at 150° C. for 48 h, centrifuged, washed, dried at 100° C. to obtain a solid powder, and calcined at 550° C. for 8 h to obtain an MFI molecular sieve encapsulated cluster catalyst; an equal volume of the solid powder is immersed in a 2.0 mol / L ammonium chloride solution, ion exchanged at 80° C. for 48 h, filtered, washed, dried at 100° C., and calcined at 550° C. for 8 h to obtain an MFI molecular sieve encapsulated cluster catalyst containing B acid. The active component In, the first metal promoter Zr and the second metal promoter Ga in the catalyst exist in the form of clusters inside the pores and on the outer surface of the synthesized MFI molecular sieve carrier.

[0102] The obtained catalyst was used in the reaction of preparing C4 hydrocarbons from synthesis gas. The reaction conditions were: the volume ratio of CO and H2 in the synthesis gas was 1:4, and the synthesis gas volume space velocity was 2000h -1 , the catalytic reaction temperature is 320°C, the catalytic reaction pressure is 4MPa, and the reaction test results are shown in Table 1.

[0103] Example 3

[0104] A method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas:

[0105] 1.77 g of tetraethylammonium hydroxide, 8.32 g of tetramethyl orthosilicate, 56.8 mg of aluminum nitrate and 14.4 g of water were mixed in a hydrothermal kettle and stirred at 40°C for 12 h; 63.6 mg of indium nitrate, 200 mg of ethylenediamine, 90.2 mg of zirconium nitrate and 56.3 mg of zinc nitrate were added to the hydrothermal kettle, heat treated at 150°C for 48 h, centrifuged, washed, dried at 100°C to obtain a solid powder, and calcined at 550°C for 8 h to obtain a Beta molecular sieve encapsulated nanocluster catalyst; an equal volume of the solid powder was immersed in a 2.0 mol / L ammonium chloride solution, ion exchanged at 80°C for 48 h, filtered, washed, dried at 100°C, and calcined at 550°C for 8 h to obtain a BEA* molecular sieve encapsulated cluster catalyst containing B acid, whose XRD pattern is shown as follows: Figure 2 The active component In, the first metal promoter Zr and the second metal promoter Zn in the catalyst exist in the form of clusters inside the pores and on the outer surface of the synthesized BEA* molecular sieve carrier.

[0106] The obtained catalyst was used in the reaction of preparing C4 hydrocarbons from synthesis gas. The reaction conditions were: the volume ratio of CO and H2 in the synthesis gas was 1:4, and the synthesis gas volume space velocity was 2000h -1 , the catalytic reaction temperature is 320°C, the catalytic reaction pressure is 4MPa, and the reaction test results are shown in Table 1.

[0107] Example 4

[0108] A method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas:

[0109] 1.77 g of tetraethylammonium hydroxide, 8.32 g of tetramethyl orthosilicate, 56.8 mg of aluminum nitrate and 14.4 g of water were mixed in a hydrothermal kettle and stirred at 40° C. for 12 h; 63.6 mg of indium nitrate, 200 mg of ethylenediamine, 90.2 mg of zirconium nitrate and 88.4 mg of gallium nitrate were added to the hydrothermal kettle, heat treated at 150° C. for 48 h, centrifuged, washed, dried at 100° C. to obtain a solid powder, and calcined at 550° C. for 8 h to obtain a Beta molecular sieve encapsulated nanocluster catalyst; an equal volume of the solid powder was immersed in a 2.0 mol / L ammonium chloride solution, ion exchanged at 80° C. for 48 h, filtered, washed, dried at 100° C., and calcined at 550° C. for 8 h to obtain a BEA* molecular sieve encapsulated cluster catalyst containing B acid. The active component In, the first metal promoter Zr and the second metal promoter Ga in the catalyst exist in the form of clusters inside the pores and on the outer surface of the synthesized BEA* molecular sieve carrier.

[0110] The obtained catalyst was used in the reaction of preparing C4 hydrocarbons from synthesis gas. The reaction conditions were: the volume ratio of CO and H2 in the synthesis gas was 1:4, and the synthesis gas volume space velocity was 2000h -1, the catalytic reaction temperature is 320°C, the catalytic reaction pressure is 4MPa, and the reaction test results are shown in Table 1.

[0111] Example 5

[0112] A method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas:

[0113] 0.83 g of tetramethyl orthosilicate, 0.34 g of aluminum nitrate, 64 mg of sodium hydroxide and 1.4 g of water were mixed in a hydrothermal kettle and stirred at 45° C. for 8 h; 77.4 mg of indium nitrate, 200 mg of ethylenediamine, 137.8 mg of zirconium nitrate, 86 mg of zinc nitrate, 7.49 g of tetramethyl orthosilicate, 3.06 g of aluminum nitrate and 576 mg of sodium hydroxide were added to the hydrothermal kettle, heat treated at 150° C. for 48 h, centrifuged, washed, dried at 100° C. to obtain a solid powder, and calcined at 550° C. for 8 h to obtain a FAU molecular sieve encapsulated nanocluster catalyst; an equal volume of the solid powder was immersed in a 2.0 mol / L ammonium chloride solution, ion exchanged at 80° C. for 48 h, filtered, washed, dried at 100° C., and calcined at 550° C. for 8 h to obtain a FAU molecular sieve encapsulated cluster catalyst containing B acid. The active component In, the first metal promoter Zr and the second metal promoter Zn in the catalyst exist in the form of clusters inside the pores and on the outer surface of the synthesized FAU molecular sieve carrier.

[0114] The obtained catalyst was used in the reaction of preparing C4 hydrocarbons from synthesis gas. The reaction conditions were: the volume ratio of CO and H2 in the synthesis gas was 1:4, and the synthesis gas volume space velocity was 2000h -1 , the catalytic reaction temperature is 320°C, the catalytic reaction pressure is 4MPa, and the reaction test results are shown in Table 1.

[0115] Example 6

[0116] A method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas:

[0117] 0.83 g of tetramethyl orthosilicate, 0.34 g of aluminum nitrate, 64 mg of sodium hydroxide and 1.4 g of water were mixed in a hydrothermal kettle and stirred at 45° C. for 8 h; 77.4 mg of indium nitrate, 200 mg of ethylenediamine, 110.3 mg of zirconium nitrate, 135.2 mg of gallium nitrate, 7.49 g of tetramethyl orthosilicate, 3.06 g of aluminum nitrate and 576 mg of sodium hydroxide were added to the hydrothermal kettle, heat treated at 150° C. for 48 h, centrifuged, washed, dried at 100° C. to obtain a solid powder, and calcined at 550° C. for 8 h to obtain a FAU molecular sieve encapsulated nanocluster catalyst; an equal volume of the solid powder was immersed in a 2.0 mol / L ammonium chloride solution, ion exchanged at 80° C. for 48 h, filtered, washed, dried at 100° C., and calcined at 550° C. for 8 h to obtain a FAU molecular sieve encapsulated cluster catalyst containing B acid. The active component In, the first metal promoter Zr and the second metal promoter Ga in the catalyst exist in the form of clusters inside the pores and on the outer surface of the synthesized FAU molecular sieve carrier.

[0118] The obtained catalyst was used in the reaction of preparing C4 hydrocarbons from synthesis gas. The reaction conditions were: the volume ratio of CO and H2 in the synthesis gas was 1:4, and the synthesis gas volume space velocity was 2000h -1 , the catalytic reaction temperature is 320°C, the catalytic reaction pressure is 4MPa, and the reaction test results are shown in Table 1.

[0119] Comparative Example 1

[0120] The difference from Example 1 is that the second metal additive zinc nitrate is not added.

[0121] Comparative Example 2

[0122] The difference from Example 1 is that the added amount of aluminum nitrate is 568 mg.

[0123] In the present invention, the product analysis method in the embodiments and comparative examples adopts Agilent chromatography analysis, and the specific detection method of each hydrocarbon product is:

[0124] Injection volume: 0.5 μL; chromatographic column: Agilent alumina model (50m*530um*10um); column temperature: 40°C for 3 min, increase to 75°C at 5°C / min, maintain for 1 min, increase to 190°C at 10°C / min, maintain for 10 min; injection port temperature 220°C; detector temperature: 250°C.

[0125] Septum purge gas flow rate: 3ml / min; chromatographic column flow rate (N2): 9ml / min; split injection, split ratio is 10:1; hydrogen flow rate: 40ml / min; air flow rate: 350ml / min; tail gas purge flow rate: 25ml / min.

[0126] Table 1 Comparison of catalyst performance evaluation of examples and comparative examples

[0127]

[0128]

[0129] As can be seen from Table 1, in Examples 1-6, by encapsulating metal active components and metal additives using molecular sieves, the size of the composite metal oxide clusters can be restricted by the molecular sieve microchannels, thereby reducing the size of the clusters, significantly increasing the active centers on the active components, and improving the catalytic activity of the catalyst.

[0130] In Comparative Example 1, due to the lack of the second metal additive, the dispersibility and electronic effect of the active component cannot be adjusted, and the catalytic activity is lower than that of Examples 1-6 at the same dosage.

[0131] The carrier of Comparative Example 2 has a relatively low silicon-aluminum ratio, low acid content and acid sites, and its selectivity for low-carbon hydrocarbon products, especially C4 hydrocarbons, is lower than that of Examples 1-6.

[0132] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements 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.

[0133] In addition, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present invention and form different embodiments. For example, in the above claims, any one of the claimed embodiments may be used in any combination. The information disclosed in this background technology section is intended only to deepen the understanding of the overall background technology of the present invention and should not be regarded as an admission or in any form of suggestion that the information constitutes prior art known to those skilled in the art.

Claims

1. A catalyst for preparing C4 hydrocarbons from synthesis gas, characterized in that: The catalyst comprises an active component, a first metal promoter, a second metal promoter and a carrier; The active component, the first metal auxiliary agent and the second metal auxiliary agent exist in the form of clusters inside the pores and on the outer surface of the carrier.

2. The catalyst according to claim 1, characterized in that The active component includes In; And / or, the first metal additive includes Zr; And / or, the second metal additive includes Zn and / or Ga; And / or, the carrier comprises a molecular sieve carrier.

3. The catalyst according to claim 1 or 2, characterized in that The carrier includes one or more of a ZSM-5 molecular sieve with an MFI topology structure, a Y molecular sieve with a FAU topology structure, and a Beta molecular sieve with a BEA* topology structure.

4. A method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas according to claims 1-3, characterized in that: The steps include: (1) mixing a molecular sieve template, a silicon source, an aluminum source, potassium chloride and water in a mass ratio of (0.1-3.0):(15-50):(1-10):(0.5-5.0):100 in a hydrothermal kettle and stirring to obtain a carrier precursor; wherein the molecular sieve template, silicon source, aluminum source and potassium chloride are calculated by metal mass; (2) adding a water-soluble active component precursor, an encapsulation promoter, a water-soluble precursor of the first metal promoter and a water-soluble precursor of the second metal promoter to the hydrothermal kettle according to the mass ratio of the active component: encapsulation promoter: first metal promoter: second metal promoter: carrier precursor being (0.5-2.0):(0.5-2.0):(0.5-2.0):(0.2-1.0):100, heat treating, centrifuging, washing and drying to obtain a solid powder; wherein the mass of the active component is measured by the amount of the active metal element; (3) calcining the solid powder to obtain the MFI molecular sieve encapsulated cluster catalyst; (4) Immersing an equal volume of the MFI molecular sieve encapsulated cluster catalyst in an ammonium chloride solution, performing ion exchange, filtering, washing, drying, and calcining to obtain a MFI molecular sieve encapsulated cluster catalyst containing B acid.

5. The method for preparing the catalyst according to claim 4, characterized in that: The molecular sieve template agent includes one or more of tetrapropylammonium hydroxide, tetraethylammonium hydroxide or tetrabutylammonium hydroxide; and / or, the encapsulation promoter comprises one or more of ethylenediamine, 1,3-butanediamine or 1,4-butanediamine; and / or, the water-soluble active component precursor comprises indium nitrate and / or indium chloride; And / or, the water-soluble precursor of the first metal additive includes zirconium nitrate and / or zirconium chloride; And / or, the water-soluble precursor of the second metal additive includes one or more of zinc chloride, zinc nitrate, gallium nitrate or gallium chloride; And / or, the stirring temperature is 30-50°C and the stirring time is 6-24h; And / or, the heat treatment is performed at 100-200° C. for 12-96 h; And / or, the concentration of the ammonium chloride solution is 1.0-3.0 mol / L; And / or, the ion exchange temperature is 60-100° C., and the ion exchange time is 24-96 h; And / or, in step (3) and step (4), the calcination temperature is 500-650° C. and the calcination time is 5-15 h.

6. A method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas according to claims 1-3, characterized in that: The steps include: (1) mixing a silicon source, an aluminum source, sodium hydroxide and water in a mass ratio of (5-10):(2-10):(0.5-2.0):100 in a hydrothermal kettle, stirring and aging to prepare a structure directing agent; wherein the silicon source, the aluminum source and the sodium hydroxide are calculated by metal mass; (2) according to the mass ratio of the active component: encapsulation promoter: first metal auxiliary agent: second metal auxiliary agent: structure directing agent being (0.5-2.0):(0.5-2.0):(0.5-2.0):(0.2-1.0):100, a water-soluble active component precursor, an encapsulation promoter, a water-soluble precursor of the first metal auxiliary agent and a water-soluble precursor of the second metal auxiliary agent are added to the hydrothermal kettle, and at the same time, a silicon source, an aluminum source and sodium hydroxide are added in the same proportion as step (1) but 5-10 times the amount of step (1), heat treatment, centrifugation, washing and drying are performed to obtain a solid powder; wherein the mass of the active component is measured by the amount of the active metal element; (3) calcining the solid powder to obtain the FAU molecular sieve encapsulated nanocluster catalyst; (4) Immersing an equal volume of the FAU molecular sieve encapsulated nanocluster catalyst in an ammonium chloride solution, performing ion exchange, filtering, washing, drying, and calcining to obtain a FAU molecular sieve encapsulated cluster catalyst containing B acid.

7. The method for preparing a catalyst according to claim 6, characterized in that: In step (1) and step (2), the encapsulation promoter includes one or more of ethylenediamine, 1,3-butanediamine or 1,4-butanediamine; and / or, the water-soluble active component precursor comprises indium nitrate and / or indium chloride; And / or, the water-soluble precursor of the first metal additive includes zirconium nitrate and / or zirconium chloride; And / or, the water-soluble precursor of the second metal additive includes one or more of zinc chloride, zinc nitrate, gallium nitrate or gallium chloride; And / or, the stirring temperature is 25-50°C and the stirring time is 2-10h; And / or, the heat treatment is performed at 80-150° C. for 12-48 hours; And / or, the concentration of the ammonium chloride solution is 1.0-3.0 mol / L; And / or, the ion exchange temperature is 60-110° C., and the ion exchange time is 12-96 h; And / or, in step (3) and step (4), the calcination temperature is 500-650° C. and the calcination time is 5-15 h.

8. A method for preparing a catalyst for preparing C4 hydrocarbons from synthesis gas according to claims 1-3, characterized in that: The steps include: (1) mixing a silicon source, an aluminum source, a template and water in a mass ratio of (15-50):(1-10):(0.1-3.0):100 in a hydrothermal kettle and stirring to obtain a carrier precursor; wherein the silicon source, the aluminum source and the template are calculated by metal mass; (2) adding a water-soluble active component precursor, an encapsulation promoter, a water-soluble precursor of the first metal promoter and a water-soluble precursor of the second metal promoter to the hydrothermal kettle according to the mass ratio of the active component: encapsulation promoter: first metal promoter: second metal promoter: carrier precursor being (0.5-2.0):(0.5-2.0):(0.5-2.0):(0.2-1.0):100, heat treating, centrifuging, washing and drying to obtain a solid powder; wherein the mass of the active component is measured by the amount of the active metal element; (3) calcining the solid powder to obtain a Beta molecular sieve encapsulated nanocluster catalyst; (4) Immersing an equal volume of the Beta molecular sieve encapsulated nanocluster catalyst in an ammonium chloride solution, performing ion exchange, filtering, washing, drying, and calcining to obtain a BEA* molecular sieve encapsulated cluster catalyst containing B acid.

9. The method for preparing a catalyst according to claim 8, characterized in that: The template comprises tetraethylammonium hydroxide and / or tetraethylammonium bromide; and / or, the encapsulation promoter comprises one or more of ethylenediamine, 1,3-butanediamine or 1,4-butanediamine; and / or, the water-soluble active component precursor comprises indium nitrate and / or indium chloride; And / or, the water-soluble precursor of the first metal additive includes zirconium nitrate and / or zirconium chloride; And / or, the water-soluble precursor of the second metal additive includes one or more of zinc chloride, zinc nitrate, gallium nitrate or gallium chloride; And / or, the stirring temperature is 20-50°C and the stirring time is 4-24h; And / or, the heat treatment is performed at 110-200° C. for 24-144 h; And / or, the concentration of the ammonium chloride solution is 1.0-3.0 mol / L; And / or, the ion exchange temperature is 60-110° C., and the ion exchange time is 12-96 h; And / or, in step (3) and step (4), the calcination temperature is 450-650° C. and the calcination time is 8-24 h.

10. Use of the catalyst according to any one of claims 1 to 3 in the reaction of preparing C4 hydrocarbons from synthesis gas, characterized in that: The application conditions are: The volume ratio of CO and H2 in the synthesis gas is 1:(1-5), the catalytic reaction temperature is 280-350℃, the catalytic reaction pressure is 2.5-6MPa, and the synthesis gas volume space velocity is 1000-3000h -1 .

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