Ru-based catalyst for directly preparing olefin from synthesis gas, forming method and application of Ru-based catalyst

Abstract

The invention provides a Ru-based catalyst for direct preparation of olefin from synthesis gas, a forming method and application thereof, and the forming method comprises the following steps: dipping a strip-shaped carrier subjected to extrusion forming in a precursor solution, drying and roasting to obtain the formed Ru-based catalyst; the precursor solution is formed by mixing a soluble salt corresponding to a Ru element, a soluble salt corresponding to a first metal M1 element and a soluble salt corresponding to a second metal M2 element. According to the invention, the carrier material is extruded into the strip-shaped carrier through the banded extruder, and the active component is loaded on the strip-shaped carrier through impregnation, so that small-size catalyst particles are obtained, the influence of diffusion limitation of a fixed bed reactor is reduced, the uniform distribution of the active component is ensured, and the catalytic performance and stability of the catalyst are improved; the catalyst has high CO conversion rate and low methane and CO2 total selectivity when being applied to a reaction for preparing olefin from synthesis gas, meanwhile, the total olefin selectivity is high, and particularly, the yield of C5 + olefin is remarkable.

Description

Technical Field

[0001] The invention belongs to the technical field of catalyst material preparation, and in particular relates to a Ru-based catalyst for direct preparation of olefins from synthesis gas, a molding method and application thereof. Background Art

[0002] As an important basic raw material for the petrochemical industry, linear alpha olefins (LAO) play a key role in the high-end polyolefin and high-end lubricant industries due to their unique molecular structure and properties. However, my country needs to import a large amount of LAO and its derivatives every year to meet industrial demand, which not only increases corporate costs but also restricts the development of related industrial chains. As an important industrial chemical reaction, direct production of olefins from synthesis gas can convert synthesis gas (a mixture of carbon monoxide and hydrogen) into high-value-added olefin products, providing an effective way for the chemical conversion of fossil fuels such as natural gas and coal.

[0003] In the process of direct synthesis of olefins from synthesis gas, the performance of the catalyst is crucial, directly affecting the reaction rate, product selectivity and catalyst stability. In recent years, ruthenium (Ru)-based catalysts have attracted widespread attention in the field of direct synthesis of olefins from synthesis gas due to their high activity, high selectivity and good stability. However, the preparation and industrial application of ruthenium-based catalysts still face challenges, especially the catalyst molding method. The catalyst particles prepared by traditional molding methods are large, difficult to diffuse, and have low strength. These problems limit the performance and stability of the catalyst, which in turn affects its industrial application.

[0004] Therefore, it is necessary to provide an improved technical solution to address the above-mentioned deficiencies in the prior art, aiming to obtain smaller catalyst particles, reduce diffusion limitations, ensure uniform distribution of active components on the carrier, thereby improving the performance and stability of the catalyst, and providing an efficient and stable catalyst for the industrial application of direct production of olefins from synthesis gas. Summary of the invention

[0005] In view of the shortcomings of the prior art described above, the object of the present invention is to provide a Ru-based catalyst for direct synthesis of olefins from synthesis gas, a molding method and its application, so as to solve the problems in the prior art that the catalyst particles used for direct synthesis of olefins from synthesis gas are large, difficult to diffuse, and have low strength, which limits its catalytic performance and stability.

[0006] To achieve the above-mentioned purpose and other related purposes, the present invention provides a molding method for a Ru-based catalyst for direct production of olefins from synthesis gas, the molding method comprising the following steps: immersing an extruded strip-shaped carrier in a precursor solution, drying and calcining to obtain a molded Ru-based catalyst; the precursor solution is a mixture of a soluble salt corresponding to the Ru element, a soluble salt corresponding to the first metal M1 element, and a soluble salt corresponding to the second metal M2 element.

[0007] Preferably, the soluble salt corresponding to the Ru element is selected from one or a combination of ruthenium nitrate, ruthenium trichloride, and ruthenium acetylacetonate.

[0008] Preferably, the M1 element is selected from one or a combination of Na, K, Ca and Mg elements.

[0009] Preferably, the M2 element is selected from one or a combination of Mn, Zn, Ce and La elements.

[0010] Preferably, in the precursor solution, the mass ratio of Ru, M1 and M2 elements is 1:(0-0.3):(0-0.3).

[0011] Preferably, when preparing the precursor solution, a surface dispersant is also added, and the surface dispersant is selected from one of polyvinyl pyrrolidone, glucose, and ethylenediaminetetraacetic acid.

[0012] Preferably, the mass ratio between the added amount of the surface dispersant and the Ru element is 0.1-1.

[0013] Preferably, the molding method of the strip-shaped carrier includes the following steps: mixing the carrier powder and the auxiliary agent evenly, adding them to a mixed solution containing a regulator and water, then adding a binder, mixing and stirring, kneading and kneading evenly, extruding and molding, drying at 60-80°C, and then calcining at 400-600°C for 2-12 hours to obtain a molded strip-shaped carrier.

[0014] Preferably, based on the total mass of the carrier powder, auxiliary agent and binder, the mass percentage of the carrier powder is 80wt% to 95wt%, the mass percentage of the auxiliary agent is 1wt% to 5wt%, and the mass percentage of the binder is 1wt% to 5wt%.

[0015] Preferably, the mass ratio of the regulator to the carrier powder is 1% to 5%.

[0016] Preferably, the carrier powder is selected from one or a combination of SiO2, Al2O3, TiO2, and pure Si molecular sieve.

[0017] Preferably, the auxiliary agent is selected from one or a combination of starch, sesbania powder, graphite, activated carbon and hydroxymethyl cellulose.

[0018] Preferably, the regulator is selected from one or a combination of oxalic acid, citric acid, nitric acid, polyethylene glycol, polyvinyl alcohol, acetic acid, NaOH, and ammonia water.

[0019] Preferably, the binder is selected from one or a combination of glycerol, silica sol, sodium silicate and aluminum sol.

[0020] Preferably, the impregnation process is specifically to use a rotary spray impregnation method to evenly spray the precursor solution onto the surface of the strip-shaped carrier.

[0021] Preferably, the drying temperature is 60-80° C.; the calcination is carried out in an air atmosphere at a temperature of 300-550° C. and a calcination time of 2-12 hours.

[0022] Preferably, in the molded Ru-based catalyst, the mass ratio between the Ru element and the strip-shaped carrier is 0.5 wt% to 5 wt%.

[0023] The present invention also provides a Ru-based catalyst formed by the above-mentioned forming method, wherein the compressive strength of the Ru-based catalyst is not less than 50N / cm.

[0024] The present invention also provides an application of the Ru-based catalyst in a synthesis gas to olefins reaction, wherein the Ru-based catalyst is used in the synthesis gas to olefins reaction at a reaction temperature of 250 to 270° C. and / or a reaction pressure of 5 to 12 bar.

[0025] As described above, the Ru-based catalyst for direct synthesis of olefins from synthesis gas, the molding method and the application thereof of the present invention have the following characteristics:

[0026] Beneficial effects:

[0027] The present invention extrude the carrier material into a strip carrier by an extruder, and then load the active component onto the strip carrier by impregnation to obtain small-sized catalyst particles, thereby reducing the influence of diffusion limitation of the fixed bed reactor and ensuring the uniform distribution of the active component, thereby improving the catalytic performance and stability of the catalyst; at the same time, the molding method is simple and the raw material cost is low, which is suitable for large-scale production, reduces the production cost of the catalyst, and improves the economic benefit.

[0028] The present invention improves the catalytic performance and stability of the Ru-based catalyst by improving the molding method of the Ru-based catalyst, and provides a catalyst with high activity, high selectivity and stability for the industrial application of direct synthesis of olefins from synthesis gas; the molded catalyst of the present invention shows a CO conversion rate of more than 85% in the synthesis gas to olefin reaction, a total selectivity of methane and CO2 of less than 7%, and a total olefin selectivity of more than 70%, especially C5 + The yield of olefins is remarkable, C5 + The yield of olefins is greater than 0.08 g / gcat / h, which can more effectively produce high value-added products in industrial applications and promote the development of the domestic polyolefin industry. DETAILED DESCRIPTION

[0029] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0030] Before further describing the specific embodiments of the present invention, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments described below; it should also be understood that the terms used in the examples of the present invention are intended to describe specific embodiments, rather than to limit the scope of protection of the present invention. The test methods in the following examples without specifying specific conditions are generally carried out under conventional conditions or under conditions recommended by the manufacturers.

[0031] When the embodiments give numerical ranges, it should be understood that, unless otherwise specified in the present invention, both endpoints of each numerical range and any numerical value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those generally understood by those skilled in the art. In addition to the specific methods, equipment, and materials used in the embodiments, according to the grasp of the prior art by those skilled in the art and the record of the present invention, any methods, equipment, and materials of the prior art similar or equivalent to the methods, equipment, and materials described in the embodiments of the present invention can also be used to realize the present invention.

[0032] The problems existing in the molding method of traditional catalysts, such as large catalyst particles, difficulty in diffusion, and low strength, will affect the performance and stability of the catalyst, thus limiting its industrial application. The traditional molding method usually presses the raw materials of the catalyst into a specific shape, such as granules or strips, for easy use in industrial reactors. Although this method can improve the mechanical strength of the catalyst, it will limit the accessibility and diffusibility of the active components.

[0033] To solve these problems, the present invention provides a molding method for a Ru-based catalyst for direct production of olefins from synthesis gas, the molding method comprising the following steps: immersing an extruded strip-shaped carrier in a precursor solution, drying and calcining to obtain a molded Ru-based catalyst; the precursor solution is a mixture of a soluble salt corresponding to the Ru element, a soluble salt corresponding to the first metal M1 element, and a soluble salt corresponding to the second metal M2 element.

[0034] Specifically, a strip carrier of a certain shape is obtained by extrusion molding, and the active components are loaded onto the strip carrier by impregnation to obtain smaller catalyst particles, reduce the impact of diffusion limitation, and ensure the uniform distribution of active components on the carrier, thereby improving its catalytic performance and stability.

[0035] As an example, the soluble salt corresponding to the Ru element is selected from one or a combination of ruthenium nitrate, ruthenium trichloride, and ruthenium acetylacetonate.

[0036] As an example, the M1 element is selected from one or a combination of Na, K, Ca, and Mg elements.

[0037] Specifically, the soluble salt corresponding to the M1 element is preferably one or a combination of sodium nitrate, potassium nitrate, calcium nitrate and magnesium nitrate.

[0038] As an example, the M2 element is selected from one or a combination of Mn, Zn, Ce, and La elements.

[0039] Specifically, the soluble salt corresponding to the M2 element is preferably one or a combination of manganese nitrate, zinc nitrate, cerium nitrate, and lanthanum nitrate.

[0040] As an example, in the precursor solution, the mass ratio between Ru, M1, and M2 elements is 1:(0-0.3):(0-0.3).

[0041] Specifically, the precursor solution may not contain the M1 element, may not contain the M2 element, or may be a precursor solution containing only the Ru element.

[0042] As an example, when preparing the precursor solution, a surface dispersant needs to be added, and the surface dispersant is selected from one of polyvinyl pyrrolidone (PVP), glucose, and ethylenediaminetetraacetic acid (EDTA).

[0043] As an example, the mass ratio between the amount of the surface dispersant added and the Ru element is 0.1 to 1 (eg, 0.1, 0.3, 0.5, 0.7, 0.9, 1, etc.).

[0044] As an example, the molding method of the strip-shaped carrier includes the following steps: mixing the carrier powder and the auxiliary agent evenly, adding them to a mixed solution containing a regulator and water, then adding a binder, mixing and stirring, and kneading them evenly, after extrusion into strips, drying at 60-80°C (such as 60°C, 65°C, 70°C, 75°C, 80°C, etc.), and then placing them at 400-600°C (such as 400°C, 450°C, 500°C, 550°C, 600°C, etc.) and calcining them at 2-12h (such as 2h, 4h, 6h, 8h, 10h, 12h, etc.) to obtain a molded strip-shaped carrier.

[0045] Specifically, the extrusion molding is carried out by using an extruder, and the aperture of the extruder die used is 1mm~5mm (for example, 1mm, 2mm, 3mm, 4mm, 5mm, etc.). The strip carriers obtained with different apertures have different sizes. The larger the size, the more obvious the diffusion effect in the fixed bed reaction. Of course, in order to meet industrial production, the size cannot be too small. In a specific embodiment of the present invention, the aperture of the extruder die is preferably 2mm~2.5mm, and the obtained molded strip carrier has a suitable pore structure and mechanical strength. The molded strip carrier is a cylindrical strip, and the diameter of the strip carrier after calcination is 1.5~2mm (for example, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, etc.).

[0046] As an example, based on the total mass of the carrier powder, the auxiliary agent and the binder, the mass percentage of the carrier powder is 80wt% to 95wt% (for example, 80wt%, 85wt%, 90wt%, 95wt%, etc.), the mass percentage of the auxiliary agent is 1wt% to 5wt% (for example, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, etc.), and the mass percentage of the binder is 1wt% to 5wt% (for example, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, etc.).

[0047] As an example, the mass ratio between the regulator and the carrier powder is 1% to 5% (eg, 1%, 2%, 3%, 4%, 5%, etc.).

[0048] Specifically, the addition of the regulator is beneficial to enhance the bonding force between particles.

[0049] Preferably, the mass ratio between water and carrier powder is 1 to 4 (eg, 1, 2, 3, 4, etc.).

[0050] As an example, the carrier powder is selected from one or a combination of SiO2, Al2O3, TiO2, and pure Si molecular sieve. Preferably, the carrier powder is SiO2 or TiO2.

[0051] Preferably, the particle size of the carrier powder is greater than 200 meshes. The finer the carrier powder, the closer the contact between the particles, and the more the strength of the strip carrier after forming can meet the requirements.

[0052] As an example, the auxiliary agent is selected from one or a combination of starch, sesbania powder, graphite, activated carbon, and hydroxymethyl cellulose.

[0053] As an example, the regulator is selected from one or a combination of oxalic acid, citric acid, nitric acid, polyethylene glycol, polyvinyl alcohol, acetic acid, NaOH, and ammonia water.

[0054] As an example, the binder is selected from one or a combination of glycerol, silica sol, sodium silicate, and aluminum sol.

[0055] Preferably, the binder is one of silica sol and sodium silicate or a mixture thereof.

[0056] As an example, in the Ru-based catalyst forming method, the impregnation process is specifically to use a rotary spray impregnation method to evenly spray the precursor solution onto the surface of the strip carrier.

[0057] As an example, in the molding method of Ru-based catalyst, the drying temperature is 60-80°C (for example, 60°C, 65°C, 70°C, 75°C, 80°C, etc.); the calcination is carried out in an air atmosphere, the calcination temperature is 300-550°C (for example, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, etc.), and the calcination time is 2-12h (for example, 2h, 4h, 6h, 8h, 10h, 12h, etc.).

[0058] As an example, in the shaped Ru-based catalyst, the mass ratio between the Ru element and the strip-shaped carrier is 0.5 wt % to 5 wt %.

[0059] Specifically, in the molded Ru-based catalyst, the loading amount of Ru may include 0.5 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, and the like.

[0060] The present invention also provides a Ru-based catalyst formed by the above-mentioned forming method, and the compressive strength of the Ru-based catalyst is not less than 50N / cm.

[0061] In addition, the present invention also provides an application of a Ru-based catalyst in a synthesis gas to olefins reaction, wherein the Ru-based catalyst is used in the synthesis gas to olefins reaction, and the reaction temperature is 250-270°C (e.g., 250°C, 255°C, 260°C, 265°C, 270°C, etc.); and / or the reaction pressure is 5-12 bar (e.g., 5 bar, 6 bar, 8 bar, 10 bar, 12 bar, etc.).

[0062] In order to better understand the Ru-based catalyst, molding method and application thereof for direct synthesis of olefins from synthesis gas in the present invention, the Ru-based catalyst, molding method and application thereof for direct synthesis of olefins from synthesis gas in the present invention are described below with reference to specific embodiments. It should be noted that these embodiments are merely descriptive and do not limit the present invention in any way.

[0063] Example 1

[0064] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0065] S1. Preparation of strip carrier: 10 g of carrier powder (SiO2 powder) and 0.5 g of auxiliary agent (starch) were mixed evenly, and added to a mixed solution containing 0.2 g of regulator (ammonia water) and 20 g of water, and then a binder (0.1 g of silica sol and 0.05 g of sodium silicate) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder mold (with a circular hole having an aperture of 2 mm). The formed carrier was placed in an oven at 60° C. and dried for 4 h, and then calcined at 450° C. in an air atmosphere in a muffle furnace for 6 h to obtain a strip carrier having a diameter of 1.5 mm.

[0066] S2. Preparation of a precursor solution: uniformly disperse a soluble salt containing 0.2 g of Ru element, a soluble salt containing 0.03 g of Na and 0.03 g of K element, and a soluble salt containing 0.03 g of Mn and 0.02 g of Ce element in water, and then add 0.02 g of a surface dispersant (PVP) and stir evenly to obtain a precursor solution;

[0067] S3. Immerse the formed strip carrier in the precursor solution, and use the rotary spray impregnation method to evenly spray the precursor solution onto the surface of the strip carrier. The impregnated catalyst particles are placed in an oven at 60°C for 4 hours, and then calcined at 400°C for 4 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 60N / cm (denoted as: Ru / Na / K / Mn / Ce@SiO2).

[0068] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefins reaction in a fixed bed reactor. The specific reaction conditions are: reaction temperature is 260°C, reaction pressure is 8 bar, and the catalytic results are shown in Table 1.

[0069] Example 2

[0070] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0071] S1. Preparation of strip carrier: 15 g of carrier powder (TiO2 powder) and 0.5 g of auxiliary agent (Sesbania powder) were mixed evenly, and added to a mixed solution containing 0.3 g of regulator (citric acid) and 25 g of water, and then a binder (0.15 g of silica sol and 0.075 g of sodium silicate) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder die (with a circular hole having an aperture of 2.5 mm). The formed carrier was placed in an oven at 70°C and dried for 5 h, and then calcined at 500°C in an air atmosphere in a muffle furnace for 7 h to obtain a strip carrier having a diameter of 1.9 mm.

[0072] S2. Preparation of precursor solution: Disperse 0.2 g of soluble salt containing Ru element, 0.05 g of soluble salt corresponding to Ca element, 0.03 g of Mn and 0.02 g of soluble salt corresponding to La element uniformly in water, then add 0.03 g of surface dispersant (glucose) and stir uniformly to obtain a precursor solution;

[0073] S3. The formed strip carrier is immersed in the precursor solution, and the precursor solution is evenly sprayed onto the surface of the strip carrier by the rotary spray impregnation method. The impregnated catalyst particles are placed in an oven at 70°C for 5 hours, and then calcined at 450°C for 5 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 65N / cm (denoted as: Ru / Ca / Mn / La@TiO2).

[0074] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefin reaction. The specific reaction conditions are: reaction temperature is 250°C, reaction pressure is 6 bar, and the catalytic results are shown in Table 1.

[0075] Example 3

[0076] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0077] S1. Preparation of strip carrier: 20 g of carrier powder (SiO2 powder) and 1 g of auxiliary agent (graphite) were mixed evenly, and added to a mixed solution containing 0.4 g of regulator (NaOH) and 30 g of water, and then a binder (0.2 g of silica sol and 0.1 g of polyethylene glycol) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder mold (with a circular hole of 2.5 mm in diameter). The formed carrier was placed in a 75°C oven and dried for 6 h, and then calcined at 550°C in an air atmosphere in a muffle furnace for 8 h to obtain a strip carrier with a diameter of 2 mm.

[0078] S2. Preparation of a precursor solution: uniformly disperse a soluble salt containing 0.4 g of Ru element, a soluble salt containing 0.1 g of K element, 0.06 g of Zn and 0.03 g of Ce element in water, and then add 0.04 g of a surface dispersant (PVP) and stir evenly to obtain a precursor solution;

[0079] S3. Immerse the formed strip carrier in the precursor solution, and use the rotary spray impregnation method to evenly spray the precursor solution onto the surface of the strip carrier. The impregnated catalyst particles are placed in an oven at 75°C for 6 hours, and then calcined at 500°C for 6 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 68N / cm (denoted as: Ru / K / Zn / Ce@SiO2).

[0080] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefins reaction. The specific reaction conditions are: reaction temperature is 265°C, reaction pressure is 6 bar, and the catalytic results are shown in Table 1.

[0081] Example 4

[0082] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0083] S1. Preparation of strip carrier: 20 g of carrier powder (TiO2 powder) and 1.5 g of auxiliary agent (Sesbania powder) were mixed evenly, and added to a mixed solution containing 0.6 g of regulator (polyethylene glycol) and 35 g of water, and then a binder (0.25 g of silica sol and 0.125 g of sodium silicate) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder mold (with a circular hole having an aperture of 2.5 mm). The formed carrier was placed in an oven at 80°C and dried for 7 h, and then calcined at 600°C in an air atmosphere in a muffle furnace for 9 h to obtain a strip carrier having a diameter of 1.8 mm.

[0084] S2. Preparation of a precursor solution: a soluble salt containing 0.6 g of Ru element, a soluble salt containing 0.05 g of Na and 0.08 g of Mg element, and a soluble salt containing 0.08 g of Zn and 0.1 g of La element are uniformly dispersed in water, and then 0.06 g of a surface dispersant (PVP) is added and stirred to obtain a precursor solution;

[0085] S3. The formed strip carrier is immersed in the precursor solution, and the precursor solution is evenly sprayed onto the surface of the strip carrier by the rotary spray impregnation method. The impregnated catalyst particles are placed in an oven at 80°C for 7 hours and then calcined at 550°C for 7 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 80N / cm (denoted as: Ru / Na / Mg / Zn / La@TiO2).

[0086] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefins reaction. The specific reaction conditions are: reaction temperature is 255°C, reaction pressure is 7 bar, and the catalytic results are shown in Table 1.

[0087] Example 5

[0088] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0089] S1. Preparation of strip carrier: 20 g of carrier powder (pure Si molecular sieve) and 2 g of auxiliary agent (graphite) were mixed evenly, added to a mixed solution containing 0.8 g of regulator (nitric acid) and 40 g of water, and then a binder (0.4 g of silica sol) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder mold (with a circular hole having an aperture of 2.5 mm). The formed carrier was placed in an oven at 85° C. and dried for 7 h, and then calcined at 600° C. in an air atmosphere in a muffle furnace for 10 h to obtain a strip carrier having a diameter of 2.1 mm.

[0090] S2. Preparation of a precursor solution: uniformly disperse a soluble salt containing 0.8 g of Ru element, a soluble salt containing 0.1 g of K and 0.1 g of Ca element, and a soluble salt corresponding to 0.14 g of Ce element in water, and then add 0.08 g of a surface dispersant (EDTA) and stir evenly to obtain a precursor solution;

[0091] S3. The formed strip carrier is immersed in the precursor solution, and the precursor solution is evenly sprayed onto the surface of the strip carrier by the rotary spray impregnation method. The impregnated catalyst particles are placed in an oven at 85°C for 7 hours, and then calcined at 550°C for 8 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 90N / cm (denoted as: Ru / K / Ca / Ce@pure Si molecular sieve).

[0092] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefins reaction. The specific reaction conditions are: reaction temperature is 260°C, reaction pressure is 9 bar, and the catalytic results are shown in Table 1.

[0093] Example 6

[0094] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0095] S1. Preparation of strip carrier: 20 g of carrier powder (SiO2 powder) and 1.5 g of auxiliary agent (hydroxymethyl cellulose) were mixed evenly, and added to a mixed solution containing 0.6 g of regulator (oxalic acid) and 35 g of water, and then a binder (0.25 g of silica sol and 0.125 g of sodium silicate) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder mold (with a circular hole having an aperture of 2.5 mm). The formed carrier was placed in a 70°C oven and dried for 6 h, and then calcined at 500°C in an air atmosphere in a muffle furnace for 8 h to obtain a strip carrier having a diameter of 2 mm.

[0096] S2. Preparation of a precursor solution: uniformly disperse a soluble salt containing 0.6 g of Ru element, a soluble salt corresponding to 0.1 g of Na element, and 0.08 g of Mn and 0.1 g of Zn element in water, and then add 0.06 g of a surface dispersant (PVP) and stir evenly to obtain a precursor solution;

[0097] S3. Immerse the formed strip carrier in the precursor solution, and use the rotary spray impregnation method to evenly spray the precursor solution onto the surface of the strip carrier. The impregnated catalyst particles are placed in an oven at 70°C for 6 hours, and then calcined at 450°C for 7 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 86N / cm (denoted as: Ru / Na / Mn / Zn-@).

[0098] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefin reaction. The specific reaction conditions are: reaction temperature is 250°C, reaction pressure is 6 bar, and the catalytic results are shown in Table 1.

[0099] Example 7

[0100] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0101] S1. Preparation of strip carrier: 20 g of carrier powder (Al2O3 powder) and 2 g of auxiliary agent (Sesbania powder) were mixed evenly, and added to a mixed solution containing 0.8 g of regulator (acetic acid) and 40 g of water, and then a binder (0.125 g of sodium silicate) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder mold (with a circular hole of 2 mm in diameter). The formed carrier was placed in an oven at 80°C and dried for 7 h, and then calcined at 550°C in an air atmosphere in a muffle furnace for 9 h to obtain a strip carrier with a diameter of 1.6 mm.

[0102] S2. Preparation of precursor solution: Disperse 0.5 g of soluble salt containing Ru element, 0.02 g of soluble salt corresponding to Na element, and 0.05 g of soluble salt corresponding to Zn element uniformly in water, then add 0.08 g of surface dispersant (glucose) and stir uniformly to obtain a precursor solution;

[0103] S3. The formed strip carrier is immersed in the precursor solution, and the precursor solution is evenly sprayed onto the surface of the strip carrier by the rotary spray impregnation method. The impregnated catalyst particles are placed in an oven at 80°C for 12 hours and then calcined at 500°C for 12 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 55N / cm (denoted as: Ru / Na / Zn@Al2O3).

[0104] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefins reaction. The specific reaction conditions are: reaction temperature is 255°C, reaction pressure is 7 bar, and the catalytic results are shown in Table 1.

[0105] Example 8

[0106] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0107] S1. Preparation of strip carrier: 20 g of carrier powder (pure Si molecular sieve) and 2 g of auxiliary agent (graphite) were mixed evenly, added to a mixed solution containing 0.8 g of regulator (polyvinyl alcohol) and 40 g of water, and then a binder (0.4 g of silica sol and 0.2 g of glycerol) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder die (with a circular hole having an aperture of 2.5 mm). The formed carrier was placed in an oven at 85° C. and dried for 7 h, and then calcined at 600° C. in an air atmosphere in a muffle furnace for 10 h to obtain a strip carrier having a diameter of 2.1 mm.

[0108] S2. Preparation of a precursor solution: a soluble salt containing 0.8 g of Ru element, a soluble salt containing 0.2 g of Na and 0.1 g of K element, and a soluble salt containing 0.14 g of Mn and 0.16 g of La element are uniformly dispersed in water, and then 0.08 g of a surface dispersant (EDTA) is added and stirred to obtain a precursor solution;

[0109] S3. The formed strip carrier is immersed in the precursor solution, and the precursor solution is evenly sprayed onto the surface of the strip carrier by the rotary spray impregnation method. The impregnated catalyst particles are placed in an oven at 85°C for 7 hours, and then calcined at 550°C for 8 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 66N / cm (denoted as: Ru / Na / K / Mn / La@pure Si molecular sieve).

[0110] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefins reaction. The specific reaction conditions are: reaction temperature is 260°C, reaction pressure is 9 bar, and the catalytic results are shown in Table 1.

[0111] Example 9

[0112] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0113] S1. Preparation of strip carrier: 20 g of carrier powder (SiO2 powder) and 1.5 g of auxiliary agent (starch) were mixed evenly, and added to a mixed solution containing 0.6 g of regulator (acetic acid) and 35 g of water, and then a binder (0.25 g of silica sol and 0.125 g of sodium silicate) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder mold (with a circular hole of 2 mm in diameter). The formed carrier was placed in a 70°C oven and dried for 6 h, and then calcined at 500°C in an air atmosphere in a muffle furnace for 8 h to obtain a strip carrier with a diameter of 1.7 mm.

[0114] S2. Preparation of a precursor solution: Disperse 0.6 g of a soluble salt containing Ru element and 0.06 g of a soluble salt corresponding to Ce element uniformly in water, then add 0.06 g of a surface dispersant (PVP) and stir uniformly to obtain a precursor solution;

[0115] S3. Immerse the formed strip carrier in the precursor solution, and use the rotary spray impregnation method to evenly spray the precursor solution onto the surface of the strip carrier. The impregnated catalyst particles are placed in an oven at 70°C for 6 hours, and then calcined at 450°C for 7 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 77N / cm (denoted as: Ru / Ce@SiO2).

[0116] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefin reaction. The specific reaction conditions are: reaction temperature is 250°C, reaction pressure is 6 bar, and the catalytic results are shown in Table 1.

[0117] Example 10

[0118] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0119] S1. Preparation of strip carrier: 20 g of carrier powder (TiO2 powder) and 2 g of auxiliary agent (Sesbania powder) were mixed evenly, and added to a mixed solution containing 0.8 g of regulator (citric acid) and 40 g of water, and then a binder (0.25 g of silica sol and 0.125 g of sodium silicate) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder mold (with a circular hole having an aperture of 2.5 mm). The formed carrier was placed in an oven at 80°C and dried for 7 h, and then calcined at 550°C in an air atmosphere in a muffle furnace for 9 h to obtain a strip carrier having a diameter of 1.8 mm.

[0120] S2. Preparation of precursor solution: Disperse 0.8 g of soluble salt containing Ru element and 0.2 g of soluble salt containing Na and 0.04 g of soluble salt corresponding to Mg element uniformly in water, then add 0.08 g of surface dispersant (glucose) and stir uniformly to obtain a precursor solution;

[0121] S3. The formed strip carrier is immersed in the precursor solution, and the precursor solution is evenly sprayed onto the surface of the strip carrier by the rotary spray impregnation method. The impregnated catalyst particles are placed in an oven at 80°C for 7 hours and then calcined at 500°C for 7 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 82N / cm (denoted as: Ru / Na / Mg@TiO2).

[0122] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefins reaction. The specific reaction conditions are: reaction temperature is 255°C, reaction pressure is 7 bar, and the catalytic results are shown in Table 1.

[0123] Embodiment 11

[0124] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0125] S1. Preparation of strip carrier: 20 g of carrier powder (pure Si molecular sieve) and 2 g of auxiliary agent (graphite) were mixed evenly, added to a mixed solution containing 0.8 g of regulator (nitric acid) and 40 g of water, and then a binder (0.4 g of silica sol and 0.2 g of glycerol) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder die (with a circular hole having an aperture of 2.5 mm). The formed carrier was placed in an oven at 85° C. and dried for 7 h, and then calcined at 600° C. in an air atmosphere in a muffle furnace for 10 h to obtain a strip carrier having a diameter of 2.1 mm.

[0126] S2. Preparation of a precursor solution: Disperse 0.8 g of a soluble salt containing Ru element, 0.2 g of a soluble salt corresponding to K element, 0.14 g of Mn and 0.1 g of a soluble salt corresponding to La element uniformly in water, then add 0.08 g of a surface dispersant (glucose) and stir uniformly to obtain a precursor solution;

[0127] S3. The formed strip carrier is immersed in the precursor solution, and the precursor solution is evenly sprayed onto the surface of the strip carrier by the rotary spray impregnation method. The impregnated catalyst particles are placed in an oven at 85°C for 7 hours, and then calcined at 550°C for 8 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 67N / cm (denoted as: Ru / K / Mn / La@pure Si molecular sieve).

[0128] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefins reaction. The specific reaction conditions are: reaction temperature is 260°C, reaction pressure is 9 bar, and the catalytic results are shown in Table 1.

[0129] Example 12

[0130] This embodiment provides a method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, comprising the following steps:

[0131] S1. Preparation of strip carrier: 20 g of carrier powder (SiO2 powder) and 1.5 g of auxiliary agent (starch) were mixed evenly, and added to a mixed solution containing 0.6 g of regulator (ammonia water) and 35 g of water, and then a binder (0.25 g of silica sol and 0.125 g of sodium silicate) was added. After mixing and stirring, the mixture was kneaded evenly, and then extruded using an extruder die (with a circular hole having an aperture of 2.5 mm). The formed carrier was placed in an oven at 70°C and dried for 6 h, and then calcined at 500°C in an air atmosphere in a muffle furnace for 8 h to obtain a strip carrier having a diameter of 1.9 mm.

[0132] S2. Preparation of a precursor solution: Disperse 0.6 g of a soluble salt containing Ru element, 0.15 g of a soluble salt corresponding to Na element, 0.1 g of Mn and 0.05 g of a soluble salt corresponding to Ce element uniformly in water, then add 0.06 g of a surface dispersant (PVP) and stir uniformly to obtain a precursor solution;

[0133] S3. The formed strip carrier is immersed in the precursor solution, and the precursor solution is evenly sprayed onto the surface of the strip carrier by the rotary spray impregnation method. The impregnated catalyst particles are placed in an oven at 70°C for 6 hours, and then calcined at 450°C for 7 hours in an air atmosphere in a muffle furnace to obtain a formed Ru-based catalyst with a compressive strength of 64N / cm (denoted as: Ru / Na / Zn / Ce@SiO2).

[0134] This embodiment also provides a Ru-based catalyst and its application. The Ru-based catalyst formed by the molding method in this embodiment is applied to the synthesis gas to olefin reaction. The specific reaction conditions are: reaction temperature is 250°C, reaction pressure is 6 bar, and the catalytic results are shown in Table 1.

[0135] Table 1. Compressive strength and catalytic reaction performance data of Ru-based catalysts in Examples 1 to 12

[0136]

[0137] It can be seen from Examples 1-12 that the present invention obtains Ru-based catalyst particles with a smaller particle diameter through the extrusion impregnation method, and conducts relevant fixed-bed experiments on the Ru-based catalyst. At a temperature of 250-270°C and a pressure of 5-12 bar, it exhibits a CO conversion rate of more than 85%, a total selectivity of methane and CO2 of less than 7%, a total olefin selectivity of more than 70%, and a C5+ olefin yield of more than 0.08 g / gcat / h.

[0138] In summary, the present invention extrude the carrier material into a strip carrier by an extruder, and then load the active components onto the strip carrier by impregnation to obtain small-sized catalyst particles, thereby reducing the influence of the diffusion limitation of the fixed bed reactor and ensuring the uniform distribution of the active components, thereby improving the catalytic performance and stability of the catalyst; at the same time, the molding method is simple and the raw material cost is low, which is suitable for large-scale production, reduces the production cost of the catalyst, and improves the economic benefit. The present invention improves the catalytic performance and stability of the Ru-based catalyst by improving the molding method of the Ru-based catalyst, and provides a catalyst with high activity, high selectivity and stability for the industrial application of direct production of olefins from synthesis gas; the catalyst molded by the present invention exhibits a CO conversion rate of more than 85% in the synthesis gas to olefin reaction, and the total selectivity of methane and CO2 is less than 7%, while the total olefin selectivity is greater than 70%, especially C5+ The yield of olefins is remarkable, C5 + The yield of olefins is greater than 0.08 g / gcat / h, which can more effectively produce high value-added products in industrial applications and promote the development of the domestic polyolefin industry. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0139] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas, characterized in that: The molding method comprises the following steps: immersing the extruded strip carrier in a precursor solution, drying and calcining to obtain a molded Ru-based catalyst; the precursor solution is a mixture of a soluble salt corresponding to the Ru element, a soluble salt corresponding to the first metal M1 element, and a soluble salt corresponding to the second metal M2 element.

2. The method for forming a Ru-based catalyst for direct synthesis of olefins from synthesis gas according to claim 1, characterized in that: Includes one or a combination of the following conditions: The soluble salt corresponding to the Ru element is selected from one or a combination of ruthenium nitrate, ruthenium trichloride, and ruthenium acetylacetonate; The M1 element is selected from one or a combination of Na, K, Ca, and Mg elements; The M2 element is selected from one or a combination of Mn, Zn, Ce and La elements; In the precursor solution, the mass ratio of Ru, M1 and M2 elements is 1:(0-0.3):(0-0.3).

3. The molding method of Ru-based catalyst for direct synthesis of olefins from synthesis gas according to claim 1, characterized in that: When preparing the precursor solution, a surface dispersant needs to be added, and the surface dispersant is selected from one of polyvinyl pyrrolidone, glucose, and ethylenediaminetetraacetic acid.

4. The molding method of Ru-based catalyst for direct synthesis of olefins from synthesis gas according to claim 3, characterized in that: The mass ratio between the added amount of the surface dispersant and the Ru element is 0.1-1.

5. The molding method of Ru-based catalyst for direct synthesis of olefins from synthesis gas according to claim 1, characterized in that: The strip carrier forming method comprises the following steps: uniformly mixing carrier powder and auxiliary agent, adding the mixture into a mixed solution containing a regulator and water, then adding a binder, mixing and stirring, kneading and kneading the mixture uniformly, extruding and forming the strips, drying the mixture at 60-80°C, and then calcining the mixture at 400-600°C for 2-12 hours to obtain a formed strip carrier.

6. The molding method of Ru-based catalyst for direct synthesis of olefins from synthesis gas according to claim 5, characterized in that: Includes one or a combination of the following conditions: Based on the total mass of the carrier powder, the auxiliary agent and the binder, the mass percentage of the carrier powder is 90wt% to 95wt%, the mass percentage of the auxiliary agent is 1wt% to 5wt%, and the mass percentage of the binder is 1wt% to 5wt%; The mass ratio of the regulator to the carrier powder is 1% to 5%.

7. The molding method of Ru-based catalyst for direct synthesis of olefins from synthesis gas according to claim 5, characterized in that: Includes one or a combination of the following conditions: The carrier powder is selected from one or a combination of SiO2, Al2O3, TiO2, and pure Si molecular sieve; The auxiliary agent is selected from one or a combination of starch, sesbania powder, graphite, activated carbon, and hydroxymethyl cellulose; The regulator is selected from one or a combination of oxalic acid, citric acid, nitric acid, polyethylene glycol, polyvinyl alcohol, acetic acid, NaOH, and ammonia; The binder is selected from one or a combination of glycerol, silica sol, sodium silicate and aluminum sol.

8. The molding method of Ru-based catalyst for direct synthesis of olefins from synthesis gas according to claim 1, characterized in that: The impregnation process is specifically to use a rotary spray impregnation method to evenly spray the precursor solution onto the surface of the strip carrier.

9. The molding method of Ru-based catalyst for direct synthesis of olefins from synthesis gas according to claim 1, characterized in that: The drying temperature is 60-80° C.; the calcination is carried out in an air atmosphere, the calcination temperature is 300-550° C., and the calcination time is 2-12 hours.

10. The molding method of Ru-based catalyst for direct synthesis of olefins from synthesis gas according to claim 1, characterized in that: In the molded Ru-based catalyst, the mass ratio between the Ru element and the strip-shaped carrier is 0.5 wt % to 5 wt %.

11. A Ru-based catalyst formed by the forming method according to any one of claims 1 to 10, characterized in that: The compressive strength of the molded Ru-based catalyst is not less than 50 N / cm.

12. Use of the Ru-based catalyst as claimed in claim 11 in a synthesis gas to olefins reaction, characterized in that: The Ru-based catalyst is used in a synthesis gas to olefin reaction, and the reaction temperature is 250-270° C.; and / or the reaction pressure is 5-12 bar.

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