A high-thermal-conductivity catalyst for synthesis gas to olefin, a preparation method and application thereof

Abstract

The application provides a high-heat-conductivity catalyst for synthesis gas to olefin, a preparation method and application, the catalyst comprising: an active component, an alkaline auxiliary agent and a carbon nanotube network structure, the catalyst containing 20-65% of the carbon nanotube network structure in terms of mass percentage. The alkaline auxiliary agent is mainly coated on the surface of the active component in a thin layer, and the active component and the alkaline auxiliary agent form a point-like cross-interacting structure with the carbon nanotube network structure. The carbon nanotube network structure inside the catalyst can timely transfer the heat inside the catalyst to the outside by virtue of its high mass transfer and heat transfer performance, eliminate the potential high temperature inside, improve the operation life of the catalyst and prolong the action time of high olefin selectivity. Further, due to the advantage of a large aspect ratio of the carbon nanotube, the carbon nanotube existing in the catalyst can effectively wind the active phase particles, can significantly improve the overall strength of the catalyst and reduce the abrasion rate of the catalyst under a large flow rate.

Description

Technical Field

[0001] This invention relates to catalysts for the preparation of light hydrocarbons from syngas and the field of preparation technology, and particularly to a catalyst for the preparation of olefins from syngas with high thermal conductivity, its preparation method and application. Background Technology

[0002] One-step synthesis of olefins from syngas is an emerging catalytic process and represents the latest technological and industrial trend both domestically and internationally. Its main advantage lies in the fact that syngas can be produced from various sources, including coal, natural gas, biomass, diesel, and other hydrocarbons. Furthermore, the one-step olefin synthesis process eliminates the need for a methanol synthesis reactor, a high-energy-consuming methanol refining unit, and a large reactor for methanol-to-olefin synthesis. This significantly reduces parameters such as the highest temperature and pressure points, resulting in a shorter process flow, lower consumption, lower investment, and better intrinsic safety.

[0003] Analysis of the one-step synthesis of olefins from syngas reveals that it couples two processes: the production of methanol from syngas and the subsequent production of olefins from methanol (both exothermic reactions). The use of a catalyst is crucial for facilitating these conversions. However, different catalysts require different olefin production conditions. For example, composite catalysts combining metal oxides and molecular sieves, as well as metal-supported catalysts (where the active components include carbides, metals, or metal oxides), are more suitable for feedstocks with a hydrogen-to-carbon ratio of 2:1. For coal-based crude syngas and crude syngas produced from diesel, due to insufficient hydrogen, the hydrogen-to-carbon ratio may even be less than 1:1. Therefore, the catalyst needs to possess water-gas shift function (an exothermic reaction) to increase the hydrogen-to-carbon ratio in the feedstock, thereby releasing a significant amount of heat. Furthermore, the entire process operates under high pressure. Traditional catalysts, due to their large particle size, exhibit a phenomenon where the internal temperature is significantly higher than the external surface temperature or the bulk gas phase temperature of the catalyst bed. Even with a multifunctional catalyst, the extremely high internal temperature and the significant temperature difference between the inside and outside are detrimental to the long-term stable operation of the catalyst. Summary of the Invention

[0004] To address the aforementioned problems in the existing technology, this invention provides a catalyst structure with high thermal conductivity formed by carrying active components and alkaline additives on carbon nanotubes. By leveraging the high mass transfer performance of carbon nanotubes, the internal temperature of the catalyst is rapidly conducted away, achieving relatively uniform internal and external temperatures, and extending the catalyst's high olefin selectivity reaction time and service life.

[0005] The specific details of the invention are as follows:

[0006] In a first aspect, the present invention provides a catalyst for the synthesis of olefins from syngas with high thermal conductivity, characterized in that the catalyst comprises: an active component, an alkaline promoter, and a carbon nanotube network structure;

[0007] The active component includes one or more of the following: iron carbide, molybdenum carbide, cobalt carbide, gold, copper, zinc, iron, chromium, and iron(II,III) oxide, and the active component accounts for 30%-65% of the mass percentage of the catalyst.

[0008] The alkaline auxiliary agent is one or more of sodium, potassium, calcium and magnesium oxygen-containing compounds, and the alkaline auxiliary agent accounts for 5%-15% of the mass percentage of the catalyst.

[0009] The carbon nanotube network structure accounts for 20%-65% of the mass of the catalyst.

[0010] Optionally, the carbon nanotubes have a diameter of 0.5-20 nm and an aspect ratio of 200-20000.

[0011] Optionally, the active component, by mass percentage, consists of 60-65% iron carbide, 15-20% chromium, and 20-30% iron;

[0012] The active component accounts for 60-65% of the mass percentage of the catalyst.

[0013] Optionally, the particle size of the active component is 2-12 nm.

[0014] Optionally, the alkaline additive is one or a combination of two of sodium nitrate, potassium nitrate, magnesium nitrate, sodium bicarbonate, basic calcium carbonate, sodium hydroxide, potassium hydroxide, magnesium hydroxide, and calcium hydroxide.

[0015] In a second aspect, the present invention provides a method for preparing the catalyst for syngas-to-olefins as described in the first aspect above, the method comprising:

[0016] Add the active components and carbon nanotubes to the alkaline additive precursor solution, stir at 5-50℃ for 3-6 hours, then raise the temperature to 80-120℃ and continue stirring until the slurry viscosity reaches 1000-3000 mPa·S.

[0017] The slurry is extruded into strips with a diameter of 2-5 mm. The strips are then transferred to an environment of 300-450°C for calcination for 1-2 hours. After cooling, a catalyst for the synthesis of olefins from syngas is obtained.

[0018] Optionally, the alkaline auxiliary agent precursor solution is prepared by dissolving the alkaline auxiliary agent in deionized water.

[0019] Thirdly, the present invention provides an application of the catalyst for syngas-to-olefins described in the first aspect above, characterized in that it comprises:

[0020] The catalyst is loaded into a reactor, and a mixture of hydrogen and carbon monoxide with a molar ratio of 0.8:1 to 2:1 is introduced into the reactor.

[0021] Under preset reaction conditions, the mixed gas reacts with the catalyst to produce olefins.

[0022] Optionally, the preset reaction conditions are:

[0023] The gas pressure in the reactor is 2-6 MPa;

[0024] The temperature in the reactor is 250-400℃;

[0025] The catalyst mass space velocity in the reactor is 1-15 h⁻¹ -1 .

[0026] Optionally, when the carbon monoxide conversion rate is 60%-95%, the selectivity of the olefin is 70%-90%.

[0027] Alternatively, the reactor used may be an axially fixed bed or a radially fixed bed.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] The present invention provides a high thermal conductivity catalyst for syngas-to-olefins production, comprising an active component, a basic promoter, and carbon nanotubes. The active material and the basic promoter are dispersed within and on the surface of the catalyst structure. Furthermore, there is no limitation on the amount of active component loaded onto the carbon nanotubes, thus overcoming the limitations of existing supports on the loading capacity of the active component. This provides the advantage of a large active material loading volume, allowing for higher operating space velocities and improving the reactor's production efficiency.

[0030] Furthermore, since the catalyst contains 20%-65% carbon nanotubes, the one-dimensional linear structure of carbon nanotubes exhibits strong mass and heat transfer effects. This accelerates the hydrogen transfer rate during the reaction (promoting hydrogen overflow) and effectively conducts heat from the catalyst's interior to the exterior, eliminating potential internal high temperatures. This reduces the temperature difference between the inside and outside of the catalyst to within 0.5℃, improving the catalyst's operating life and extending the time for high olefin selectivity. Moreover, due to the high aspect ratio of carbon nanotubes, they can effectively entangle the active phase particles, significantly improving the overall strength of the catalyst and reducing its wear rate at high flow rates.

[0031] Furthermore, the combination of the active component and the alkaline auxiliary agent enables the catalyst to have the dual functions of olefin synthesis and water-gas shift conversion. This allows the syngas-to-olefins catalyst provided by the present invention to be used to catalyze syngas feedstocks with low hydrogen-to-carbon ratios without the need for additional water-gas shift units, effectively reducing investment in production costs, steam consumption, and carbon emissions per unit mass of olefins. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 A flowchart of the preparation method of the catalyst for syngas-to-olefins provided in the embodiments of the present invention is shown;

[0034] Figure 2 A flowchart illustrating the application of the catalyst for syngas-to-olefins provided in an embodiment of the present invention is shown. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention. Furthermore, all other embodiments obtained by those skilled in the art without inventive effort are within the protection scope of the present invention.

[0036] Specific experimental steps or conditions are not specified in the embodiments; they can be performed according to the conventional experimental steps or conditions described in the prior art. Reagents and other instruments used, unless otherwise specified, are all commercially available conventional reagent products. Furthermore, the accompanying drawings are merely illustrative diagrams of the embodiments of the present invention and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore, repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0037] Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of this specification.

[0038] In the description of this invention, it should be understood that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0039] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] In a first aspect, the present invention provides a high thermal conductivity catalyst for syngas-to-olefins production, characterized in that the catalyst comprises: an active component, a basic promoter, and a carbon nanotube network structure. By mass percentage, the catalyst contains 20%-65% carbon nanotube network structure, with the remainder being the active component and the basic promoter. The carbon nanotube network structure, the active component, and the basic promoter are tightly bonded together. The basic promoter mainly forms a thin layer coating on the surface of the active component, and the active component and the basic promoter form a point-like cross-contact structure with the carbon nanotube network structure. The carbon nanotube network structure located inside the catalyst, through its efficient mass and heat transfer properties, promptly transfers heat from the catalyst's interior to the exterior, eliminating potential internal high temperatures and reducing the temperature difference between the inside and outside of the catalyst to within 0.5°C, thereby improving the catalyst's operating life and extending the reaction time for high olefin selectivity. The carbon nanotube network structure also creates numerous mesopores within the catalyst, promoting reaction diffusion and product migration. Furthermore, due to the advantage of carbon nanotubes having a large aspect ratio, the carbon nanotubes present in the catalyst can effectively entangle the active phase particles, which can significantly improve the overall strength of the catalyst and reduce the wear rate of the catalyst under high flow rates.

[0041] In specific implementation, the particle size of the active component is 2-12 nm, accounting for 30%-65% of the mass percentage of the catalyst. The active component can be selected from one or more combinations of iron carbide, molybdenum carbide, cobalt carbide, gold, copper, zinc, iron, chromium, and iron(II,III) oxide. In terms of the mass percentage of the active component, the preferred active component consists of 60-65% iron carbide, 15-20% chromium, and 20-30% iron, accounting for 60-65% of the mass percentage of the catalyst.

[0042] In specific implementation, the alkaline additive accounts for 5%-15% of the mass of the catalyst. The alkaline additive is one or more of sodium, potassium, calcium and magnesium oxygen-containing compounds, preferably sodium nitrate, potassium nitrate, magnesium nitrate, sodium bicarbonate, sodium bicarbonate, basic calcium carbonate, sodium hydroxide, potassium hydroxide, magnesium hydroxide and calcium hydroxide, or one or two of these compounds.

[0043] Secondly, the present invention provides a method for preparing the catalyst for syngas-to-olefins as described in the first aspect above. Figure 1 A flowchart illustrating the preparation method of the catalyst for syngas-to-olefins provided in an embodiment of the present invention is shown, as follows: Figure 1 As shown, the preparation method includes the following steps:

[0044] S1. Add the active components and carbon nanotubes to the alkaline auxiliary agent precursor solution, stir at 5-50℃ for 3-6 hours, then raise the temperature to 80-120℃ and continue stirring until the slurry viscosity reaches 1000-3000mPa·S.

[0045] S2. The slurry is extruded to form strips with a diameter of 2-5 mm. The strips are then transferred to an environment of 300-450°C for calcination for 1-2 hours. After cooling, a catalyst for the synthesis of olefins from syngas is obtained.

[0046] In practice, the active component, carbon nanotubes, and basic auxiliary agent precursor solution are first stirred at 25-50℃. The carbon nanotubes form a network structure and are thoroughly mixed with the active component and basic auxiliary agent. Then, the temperature is raised to 80-120℃, and stirring continues to remove excess water from the slurry. After the slurry viscosity reaches 1000-2000 mPa·s, it is extruded, calcined, and cooled to obtain the catalyst for syngas-to-olefins production. This preparation method has the advantages of being easy to operate and low in cost. Furthermore, this preparation method does not limit the amount of active component loaded on the carbon nanotubes, thus overcoming the limitations of existing supports on the loading amount of active components, and can prepare syngas-to-olefins catalysts suitable for higher operating space velocities.

[0047] In some embodiments, the alkaline auxiliary agent precursor solution is prepared by dissolving the alkaline auxiliary agent in deionized water.

[0048] Thirdly, the present invention provides an application of the catalyst for syngas-to-olefins production described in the first aspect above. Figure 2 The following is a flowchart illustrating the application of the catalyst for syngas-to-olefins provided by the present invention: Figure 2 As shown, it includes:

[0049] S21. The catalyst is loaded into the reactor, and a mixture of hydrogen and carbon monoxide with a molar ratio of 0.8:1 to 2:1 is introduced into the reactor.

[0050] S22. Under preset reaction conditions, the mixed gas reacts with a catalyst to produce olefins.

[0051] In specific implementation, this invention uses an axially fixed bed or a radially fixed bed as a syngas-to-olefins reactor, and loads a catalyst and sets the preset reaction conditions as follows: the gas pressure in the reactor is 2-6 MPa; the temperature in the reactor is 250-400℃; and the mass hourly space velocity of the catalyst in the reactor is 1-15 h⁻¹. -1 Then, a mixture of hydrogen and carbon monoxide is introduced to prepare olefins. When the conversion rate of carbon monoxide is 60%-95%, the selectivity of olefins is 70%-90%.

[0052] To enable those skilled in the art to more clearly understand the present invention, the following embodiments are provided to illustrate in detail a high thermal conductivity catalyst for syngas-to-olefins, its preparation method, and its application.

[0053] Example 1

[0054] The active component (iron carbide, particle size 60 nm) and carbon nanotubes (diameter 20 nm, aspect ratio 200) were added together to a pre-prepared alkaline auxiliary agent precursor solution (sodium nitrate, concentration 1.2 mol / L), and stirred at 50 °C for 3 hours to obtain a mixture. The mixture was continuously stirred at 80 °C until the viscosity reached 3000 mPa·s, and then extruded to form strips with a diameter of 2 mm, which were then calcined at 300 °C for 2 hours.

[0055] The strip-shaped material was cooled to obtain a catalyst for the synthesis of olefins from syngas (the active component accounts for 30% of the mass percentage of the catalyst; the basic promoter accounts for 5% of the mass percentage of the catalyst; the carbon nanotubes account for 65% of the mass percentage of the catalyst; and the thickness of the thin layer of basic promoter on the surface of the active component is 0.5 nm). The catalyst was then stored under dry and sealed conditions.

[0056] The catalyst was loaded into a reactor, and a mixture of hydrogen and carbon monoxide in a molar ratio of 0.8:1 was introduced into the reactor; under the preset reaction conditions (gas pressure of 2 MPa for olefin synthesis; reaction temperature of 350 °C for olefin synthesis; catalyst mass hourly space velocity of 1 h⁻¹), the reaction proceeded as planned. -1 In the process of preparing olefins by performing an olefin synthesis reaction on the mixed gas under the following conditions, when the conversion rate of carbon monoxide is 60%, the selectivity of the olefins is 70%. Based on the mass of hydrogen in the synthesis gas, the hydrogen atom economy of the hydrocarbons is 85%.

[0057] Example 2

[0058] The active components (50% molybdenum carbide, 50% cobalt carbide, particle size 2 nm) and carbon nanotubes (diameter 0.5 nm, aspect ratio 20000) were added together to a pre-prepared alkaline auxiliary agent precursor solution (potassium carbonate; concentration 0.1 mol / L), and stirred at 5 °C for 6 hours to obtain a mixture. The mixture was continuously stirred at 120 °C until the viscosity reached 1000 mPa·s, and then extruded to form strips with a diameter of 5 mm, and calcined at 450 °C for 1 hour.

[0059] The strip-shaped material was cooled to obtain a catalyst for the synthesis of olefins from syngas (the active component accounts for 65% of the mass percentage of the catalyst; the basic promoter accounts for 5% of the mass percentage of the catalyst; the carbon nanotubes account for 30% of the mass percentage of the catalyst; and the thickness of the thin layer of basic promoter on the surface of the active component is 0.5 nm). The catalyst was then stored under dry and sealed conditions.

[0060] The catalyst was loaded into a reactor, and a mixture of hydrogen and carbon monoxide in a molar ratio of 2:1 was introduced into the reactor; under the preset reaction conditions (gas pressure of 6 MPa for olefin synthesis; reaction temperature of 400 °C for olefin synthesis; catalyst mass hourly space velocity of 15 h⁻¹), the reaction proceeded as planned. -1 In the process of preparing olefins by performing an olefin synthesis reaction on the mixed gas under the conditions of ), when the conversion rate of carbon monoxide is 95%, the selectivity of the olefins is 90%. Based on the mass of hydrogen in the synthesis gas, the hydrogen atom economy of the hydrocarbons is 60%.

[0061] Example 3

[0062] The active components (80% iron carbide, 2% copper, 18% iron(III) oxide, particle size 3-10 nm) and carbon nanotubes (diameter 0.5-5 nm, aspect ratio 1000) were added together to a pre-prepared alkaline auxiliary precursor solution (sodium bicarbonate, basic calcium carbonate; concentration 0.5 mol / L), and stirred at 40 °C for 5 hours to obtain a mixture. The mixture was continuously stirred at 100 °C until the viscosity reached 2000 mPa·s, and then extruded to form strips with a diameter of 3 mm, which were then calcined at 350 °C for 2 hours.

[0063] The strip-shaped material is cooled to obtain a catalyst for the synthesis of olefins from syngas (the active component accounts for 30% of the mass percentage of the catalyst; the basic promoter accounts for 15% of the mass percentage of the catalyst; the carbon nanotubes account for 55% of the mass percentage of the catalyst; and the thickness of the thin layer of basic promoter on the surface of the active component is 10 nm). The catalyst is then stored under dry and sealed conditions.

[0064] The catalyst was loaded into a reactor, and a mixture of hydrogen and carbon monoxide in a molar ratio of 1.5:1 was introduced into the reactor; under the preset reaction conditions (gas pressure of 4 MPa for olefin synthesis; reaction temperature of 250 °C for olefin synthesis; catalyst mass hourly space velocity of 2 h⁻¹), the reaction proceeded as planned. -1 In the process of preparing olefins by performing an olefin synthesis reaction on the mixed gas under the given conditions, when the conversion rate of carbon monoxide is 93%, the selectivity of the olefins is 75%. Based on the mass of hydrogen in the synthesis gas, the hydrogen atom economy of the hydrocarbons is 83%.

[0065] Example 4

[0066] The active components (30% molybdenum carbide, 0.5% gold, 39.5% iron carbide, 30% iron(II,III) oxide, with a particle size of 2-30 nm) and carbon nanotubes (10-15 nm in diameter, with an aspect ratio of 10000) were added together to a pre-prepared alkaline auxiliary precursor solution (calcium hydroxide, sodium hydroxide; concentration 1.0 mol / L). The mixture was stirred at 30 °C for 4 hours to obtain a mixture. The mixture was continuously stirred at 100 °C until the viscosity reached 2000 mPa·s. Then, it was extruded to form strips with a diameter of 4.5 mm and calcined at 380 °C for 1.2 hours.

[0067] The strip-shaped material was cooled to obtain a catalyst for the synthesis of olefins from syngas (the active component accounts for 65% of the mass percentage of the catalyst; the basic promoter accounts for 15% of the mass percentage of the catalyst; the carbon nanotubes account for 20% of the mass percentage of the catalyst; and the thickness of the thin layer of basic promoter on the surface of the active component is 9 nm). The catalyst was then stored under dry and sealed conditions.

[0068] The catalyst was loaded into a reactor, and a mixture of hydrogen and carbon monoxide in a molar ratio of 1.2:1 was introduced into the reactor. The reactor was then subjected to the preset reaction conditions (gas pressure of 3.6 MPa for olefin synthesis; reaction temperature of 290 °C; catalyst mass hourly space velocity of 6 h⁻¹). -1 In the process of preparing olefins by performing an olefin synthesis reaction on the mixed gas, when the conversion rate of carbon monoxide is 75%, the selectivity of the olefins is 80%. Based on the mass of hydrogen in the synthesis gas, the hydrogen atom economy of the hydrocarbons is 75%.

[0069] Example 5

[0070] The active components (65% iron carbide, 20% iron, 15% chromium, particle size 12-20 nm) and carbon nanotubes (diameter 15-20 nm, aspect ratio 2000) were added together to a pre-prepared alkaline auxiliary precursor solution (sodium carbonate, calcium hydroxide; concentration 0.5 mol / L), and stirred at 20 °C for 4 hours to obtain a mixture. The mixture was continuously stirred at 90 °C until the viscosity reached 1500 mPa·s, and then extruded to form strips with a diameter of 4.5 mm, which were then calcined at 320 °C for 1.5 hours.

[0071] The strip-shaped material was cooled to obtain a catalyst for the synthesis of olefins from syngas (the active component accounts for 30% of the mass percentage of the catalyst; the basic promoter accounts for 5% of the mass percentage of the catalyst; the carbon nanotubes account for 65% of the mass percentage of the catalyst; and the thickness of the thin layer of basic promoter on the surface of the active component is 1.6 nm). The catalyst was then stored under dry and sealed conditions.

[0072] The catalyst was loaded into a reactor, and a mixture of hydrogen and carbon monoxide in a molar ratio of 1.8:1 was introduced into the reactor; under the preset reaction conditions (gas pressure of 3 MPa for olefin synthesis; reaction temperature of 360 °C for olefin synthesis; catalyst mass hourly space velocity of 5 h⁻¹), the reaction proceeded as planned. -1 In the process of preparing olefins by performing an olefin synthesis reaction on the mixed gas under the conditions of ), when the conversion rate of carbon monoxide is 90%, the selectivity of the olefins is 82%. Based on the mass of hydrogen in the synthesis gas, the hydrogen atom economy of the hydrocarbons is 79%.

[0073] Example 6

[0074] The active components (45% iron carbide, 20% cobalt carbide, 35% molybdenum carbide, particle size 6-20 nm) and carbon nanotubes (diameter 6-10 nm, aspect ratio 5000) were added together to a pre-prepared alkaline auxiliary precursor solution (magnesium nitrate, sodium carbonate; concentration 0.6 mol / L), and stirred at 25 °C for 3 hours to obtain a mixture. The mixture was continuously stirred at 95 °C until the viscosity reached 2500 mPa·s, and then extruded to form hollow strips with a diameter of 4 mm (hollow diameter 1 mm), and calcined at 350 °C for 1.5 hours.

[0075] The strip-shaped material was cooled to obtain a catalyst for the synthesis of olefins from syngas (the active component accounts for 35% of the mass of the catalyst; the basic promoter accounts for 10% of the mass of the catalyst; the carbon nanotubes account for 55% of the mass of the catalyst; and the thickness of the thin layer of basic promoter on the surface of the active component is 6 nm). The catalyst was then stored under dry and sealed conditions.

[0076] The catalyst was loaded into a reactor, and a mixture of hydrogen and carbon monoxide in a molar ratio of 1.3:1 was introduced into the reactor; under the preset reaction conditions (gas pressure of 2.5 MPa for olefin synthesis; reaction temperature of 340 °C for olefin synthesis; catalyst mass hourly space velocity of 3.5 h⁻¹), the reaction proceeded as planned. -1 In the process of preparing olefins by performing an olefin synthesis reaction on the mixed gas, when the conversion rate of carbon monoxide is 84%, the selectivity of the olefins is 87.2%. Based on the mass of hydrogen in the synthesis gas, the hydrogen atom economy of the hydrocarbons is 82%.

[0077] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0078] For the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, as some steps can be performed in other orders or simultaneously according to the present invention. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and components involved are not necessarily essential to the present invention.

[0079] The above provides a detailed description of a high thermal conductivity catalyst for syngas-to-olefins production, its preparation method, and its applications. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A high thermal conductive catalyst for synthesis gas to olefin, characterized by, The catalyst comprises: an active component, an alkaline auxiliary agent, and a carbon nanotube network structure; The active component comprises a combination of one or more of iron carbide, molybdenum carbide, cobalt carbide, gold, copper, zinc, iron, chromium, and magnetite, and the active component accounts for 30%-65% of the mass percentage of the catalyst; The alkaline auxiliary agent is one or a combination of two of sodium nitrate, potassium nitrate, magnesium nitrate, sodium bicarbonate, basic calcium carbonate, sodium hydroxide, potassium hydroxide, magnesium hydroxide, and calcium hydroxide, and the alkaline auxiliary agent accounts for 5%-15% of the mass percentage of the catalyst; The carbon nanotube network structure accounts for 20%-65% of the mass percentage of the catalyst; The carbon nanotube has a diameter of 0.5-20 nm and an aspect ratio of 200-20,000; The catalyst is prepared by a method comprising the following steps: The active component and the carbon nanotube are added to an alkaline auxiliary agent precursor solution, stirred at 5-50 ℃ for 3-6 hours, and then warmed to 80-120 ℃ for continuous stirring until the slurry viscosity reaches 1,000-3,000 mPa·S; The slurry is formed into a strip with a diameter of 2-5 mm by extrusion, the strip is transferred to an environment at 300-450 ℃ for calcination for 1-2 hours, and the catalyst for preparing olefins from synthesis gas is obtained after cooling.

2. The catalyst for producing olefin from synthesis gas according to claim 1, wherein The particle size of the active component is 2-12 nm.

3. The catalyst for producing olefin from synthesis gas according to claim 1, wherein The alkaline auxiliary agent precursor solution is prepared by dissolving the alkaline auxiliary agent in deionized water.

4. Use of a catalyst according to any one of claims 1 to 3 for the synthesis of olefins from synthesis gas, characterized in that, Comprising: The catalyst is loaded into a reactor, and a mixed gas of hydrogen and carbon monoxide in a molar ratio of 0.8:1-2:1 is introduced into the reactor; Under preset reaction conditions, the mixed gas reacts under the action of the catalyst to obtain olefins.

5. Use according to claim 4, characterized in that, The preset reaction conditions are: The gas pressure in the reactor is 2-6 MPa; The temperature in the reactor is 250-400 ℃; The mass space velocity of the catalyst in the reactor is 1 -15 h -1 .

6. Use according to claim 4, characterized in that, When the carbon monoxide conversion rate is 60%-95%, the selectivity of the olefins is 70%-90%.

7. Use according to claim 4, characterized in that, The reactor used is an axial fixed bed or a radial fixed bed.

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