Bifunctional microspherical catalyst for catalyzing CO x +H2 into aromatic chemicals / liquid fuels and preparation method and application thereof

Abstract

The application provides a bifunctional microspherical catalyst for catalyzing CO x The application provides a bifunctional microspherical catalyst for catalyzing CO + H2 into aromatic chemical products / liquid fuel, a preparation method and application thereof. First, a basic metal oxide and a silicon-aluminum molecular sieve are mixed with nano-yttrium oxide modified phosphoric acid ceramic glue, and are calcined in a reducing atmosphere. Under the action of the modified yttrium oxide ceramic glue, the basic metal oxide is electrically welded on the surface of the silicon-aluminum molecular sieve to form a composite catalyst (a first precursor) in which the basic metal oxide and the silicon-aluminum molecular sieve are closely combined. Then, an acid silicon sol is used as a main binder, and an aluminum-containing glue is used as an auxiliary binder. The binder, a base material, the first precursor and deionized water are mixed to form a gel-like suspension, and the gel-like suspension is subjected to high-speed shearing treatment, spray granulation treatment and calcination treatment, so that the bifunctional microspherical catalyst with high wear resistance and the requirement of catalyst activity is prepared. The wear index of the catalyst is less than 2, and even can reach 1.2.

Description

Technical Field

[0001] This invention relates to the field of direct synthesis of aromatics from syngas, specifically to a catalyst for CO2 production. x Bifunctional microsphere catalysts for the production of aromatic chemicals / liquid fuels from H2, their preparation methods, and applications. Background Technology

[0002] As a greenhouse gas, excessive CO2 emissions can cause a series of environmental problems, such as the greenhouse effect and ocean acidification. Therefore, effectively converting CO2 into value-added chemicals can not only control atmospheric CO2 concentrations but also provide a way to replace fossil fuels and achieve sustainable development for human society. Both national renewable energy transitions and the commitment of responsible major powers to dual-carbon goals require the development of renewable liquid fuels and chemicals. Using carbon dioxide as a carbon source combined with green electricity and green hydrogen obtained from wind and solar power to produce high-value-added liquid fuels and green chemicals can be seen as a new and profitable industrial process for large-scale utilization of carbon dioxide and green hydrogen. There are two main routes for producing aromatics from a mixture of carbon dioxide and hydrogen: one is to use a methanol catalyst mixed with molecular sieves to produce aromatics via a methanol- and other oxygen-containing compound-mediated pathway, and the other is to use a modified Fischer-Tropsch catalyst mixed with molecular sieves to produce aromatics via an olefin-mediated pathway. Among them, the aromatic components prepared through the olefin-mediated pathway are mainly light aromatics such as BTX. Aromatics are prepared through the oxygen-containing compound-mediated pathway such as methanol. By controlling the reaction conditions and adjusting the physicochemical properties of the catalyst, the diversification of aromatic products can be achieved, and the production of liquid fuels with C6 to C12 as the main products can be regulated.

[0003] For process routes using fluidized bed reactors to produce aromatic chemicals / liquid fuels from carbon dioxide and hydrogen, the preparation process of the fluidized bed catalyst is crucial. Due to the small particle size and poor binding properties of molecular sieves, it is difficult to directly mold them for use as fluidized bed catalysts. Furthermore, the one-step carbon dioxide hydrogenation process requires the introduction of metal oxides to form heterojunction structures with molecular sieves, placing higher demands on the molding process. In actual production, fluidized bed catalysts generally consist of catalyst powder, binder, and matrix material. Through molding techniques, suitable catalytic activity, selectivity, stability, morphology, and wear resistance are obtained to meet the requirements of industrial processes.

[0004] The key to preparing fluidized bed catalysts is selecting a suitable binder. Currently, commonly used binders are alumina sol and silica sol. Alumina sol possesses excellent binding and forming properties, resulting in fluidized bed catalysts with high wear resistance, and is widely used in the preparation of fluidized bed catalysts for catalytic cracking processes. However, alumina sol itself is highly acidic, directly affecting the overall catalyst performance and product composition. Silica sol, on the other hand, has lower acidity, and using it as a binder in fluidized bed catalyst production has minimal impact on the molecular sieve itself, making it very suitable as a binder for catalyst forming. However, fluidized bed catalysts produced by spray granulation using commercial silica sol as a binder have poor strength, and the formed products exhibit a "hollow" phenomenon, making it difficult for the prepared catalyst products to meet the wear resistance requirements of fluidized bed processes. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, the present invention provides a method for catalyzing CO2. x A bifunctional microsphere catalyst for the production of aromatic chemicals / liquid fuels from H2, its preparation method, and its application, aiming to obtain a bifunctional microsphere catalyst with both high wear resistance and high catalytic efficiency. The specific invention details are as follows:

[0006] In a first aspect, the present invention provides a method for catalyzing CO. x A method for preparing a bifunctional microsphere catalyst for the production of aromatic chemicals / liquid fuels using H2, the method comprising the following preparation steps:

[0007] S1. After uniformly mixing the nano-yttrium oxide modified phosphate ceramic adhesive, the alkaline metal oxide, and the silica-alumina molecular sieve, the mixture is placed in a reducing atmosphere calcination furnace for calcination to obtain the first precursor; wherein, the weight ratio of the alkaline metal oxide to the silica-alumina molecular sieve is 0.1-10, and the nano-yttrium oxide modified phosphate ceramic adhesive accounts for 5%-30% of the total mass of the alkaline metal oxide and the silica-alumina molecular sieve;

[0008] S2. The first precursor is mixed evenly with binder, matrix material and deionized water to form a suspension, and then the pH is adjusted to 2.5-5.5 to make the suspension into a gel.

[0009] S3. After high-speed shearing of the suspension, the suspension is granulated by spray granulation to obtain solid microspheres. The solid microspheres are then calcined to form the bifunctional microsphere catalyst.

[0010] Optionally, in step S1, the nano-yttrium oxide modified phosphoric acid ceramic adhesive is prepared by mixing industrial phosphoric acid, aluminum hydroxide powder, silica, light magnesium oxide, yttrium oxide, and water under heating conditions, with the following mass ratio of each raw material:

[0011] Industrial phosphoric acid: 55%–58%;

[0012] Aluminum hydroxide powder: 11.5%–11.85%;

[0013] Silicic acid: 1.03%–1.05%;

[0014] Light magnesium oxide: 2.05%–2.06%;

[0015] Yttrium oxide: 0.02%–0.09%;

[0016] The rest is water.

[0017] Optionally, in step S1, the alkaline metal oxide is a single metal oxide, a bimetallic oxide, or a metal-supported oxide in which the metal is spontaneously monodispersed on the single metal oxide or bimetallic oxide, and the morphology of the alkaline metal oxide is spinel, perovskite, solid solution or mesoporous single crystal.

[0018] The silica-alumina molecular sieve is a hydrogen-type silica-alumina molecular sieve with a silica-alumina ratio of 20-200, selected from H-ZSM5, ZSM-5, ZSM-11 or ZSM-48;

[0019] The calcination conditions are as follows: the pressure inside the calcination furnace is controlled at 0.5-1 MPa, the hydrogen flow rate is 0.1-1000 ml / min, the temperature is 150-350℃, and the calcination time is 1-10 h.

[0020] Optionally, in step S1, the single metal oxide is MnO. x The bimetallic oxide is spinel ZnCrO x Or perovskite-type LaFeO3;

[0021] The silica-aluminum molecular sieve is H-ZSM5;

[0022] The weight ratio of the alkaline metal oxide to the silica-alumina molecular sieve is 1:1, and the nano-yttrium oxide modified phosphate ceramic adhesive accounts for 20% of the total mass of the alkaline metal oxide and silica-alumina molecular sieve.

[0023] Optionally, in step S2, the adhesive is composed of a mixture of silica sol and aluminum sol, wherein the dry basis mass ratio of the silica sol and aluminum sol is 1:0.01 to 0.25;

[0024] The matrix material is selected from at least one of clay, hydrotalcite, kaolin, clay, montmorillonite, bentonite, and saponin.

[0025] In the suspension, the dry matrix ratio of the first precursor, binder, and matrix material is 10-70:10-30:20-45; the mass percentage of the deionized water is 55-65%.

[0026] Optionally, in step S3, the pH of the suspension is 3.5.

[0027] Optionally, in step S3, the inlet temperature of the granulation tower used for spray granulation is 350°C and the outlet temperature is 200°C.

[0028] The roasting temperature is 300-450℃.

[0029] Secondly, the present invention provides a CO preparation method obtained by the preparation method described in the first aspect above. x Bifunctional microsphere catalyst for the production of aromatic chemicals / liquid fuels using H2.

[0030] Thirdly, the present invention provides a method for catalyzing CO obtained by the preparation method described in the first aspect above. x Application of bifunctional microsphere catalysts for the production of aromatic chemicals / liquid fuels from CO2 / CO1+H2 in fluidized bed reactors.

[0031] Optionally, the bifunctional microsphere catalyst is used in a fluidized bed reactor to catalyze CO2 production. x The catalytic conditions for the production of aromatic chemicals / liquid fuels from H2 are as follows:

[0032] The temperature is 270-380℃;

[0033] The space velocity is 300-1000 mL / h·gcat;

[0034] Hydrogen and CO x The volume ratio is 0.5 to 3.

[0035] Compared with the prior art, the present invention has the following advantages:

[0036] This invention provides a method for catalyzing CO. xA method for preparing a bifunctional microsphere catalyst for the production of aromatic chemicals / liquid fuels using +H2 involves first thoroughly mixing an alkaline metal oxide and aluminosilicate molecular sieve with a nano-yttrium oxide-modified phosphate ceramic colloid, followed by calcination in a reducing atmosphere. Under the action of the modified yttrium oxide ceramic colloid, the alkaline metal oxide is electrically welded to the surface of the aluminosilicate molecular sieve, forming a composite catalyst (first precursor) with a tight bond between the alkaline metal oxide and the aluminosilicate molecular sieve. Then, using acidic silica sol as the main binder and aluminum-containing colloid as an auxiliary binder, the binder, matrix material, first precursor, and deionized water are mixed to form a gel-like suspension, which undergoes high-speed shearing, spray granulation, and calcination to prepare a bifunctional microsphere catalyst with high wear resistance and maintained catalyst activity, exhibiting an wear index of less than 2, and even reaching 1.2. Experimental results show that this bifunctional microsphere catalyst achieves a single-pass carbon dioxide conversion rate of over 30% in the catalytic reaction of carbon dioxide hydrogenation to aromatic chemicals / liquid fuels in a fluidized bed reactor, with a C6-C12 liquid fuel selectivity of over 80%, an aromatic selectivity of over 90%, and a methane selectivity of less than 3%, demonstrating excellent prospects for carbon neutralization applications. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of this application 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 this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 A flowchart illustrating the preparation method of the bifunctional microsphere catalyst provided in an embodiment of the present invention is shown;

[0039] Figure 2 The XRD pattern of the bifunctional microsphere catalyst provided in the embodiments of the present invention is shown.

[0040] Figure 3 This shows a scanning electron microscope image of the bifunctional microsphere catalyst provided in an embodiment of the present invention;

[0041] Figure 4 The temperature-programmed reduction curve of the bifunctional microsphere catalyst provided in the embodiments of the present invention is shown.

[0042] Figure 5 The image shows a scanning electron microscope (SEM) image of the bifunctional microsphere catalyst provided in an embodiment of the present invention after reaction in a fluidized bed reactor. Detailed Implementation

[0043] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection 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.

[0044] Specific experimental steps or conditions are not specified in the examples; however, 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.

[0045] In addition to high activity, good selectivity, and a specific particle size distribution, fluidized bed catalysts also require high wear resistance. Catalysts with poor mechanical strength are prone to loss during the reaction process, causing environmental pollution and potentially affecting the proper distribution of the catalyst in the dilute and dense phases, even rendering the plant inoperable. When the finished catalyst enters the reaction-regeneration system for continuous catalytic reaction, constant collisions and friction occur between catalysts, between the catalyst and the reactor wall, between the catalyst and the delivery pipeline, and between the catalyst and the regeneration system, making catalyst pulverization unavoidable. If the catalyst strength is poor, severe catalyst wear will occur during the reaction.

[0046] To reduce the wear of fluidized bed catalysts, good wear resistance is required. Existing preparation methods often use silica sol or alumina sol as binders in the preparation of fluidized bed catalysts for catalytic cracking processes. The binder is mixed with molecular sieves and then spray-dried to obtain catalyst microspheres with a certain degree of wear resistance. However, since the main component of silica sol is SiO2, the catalytic performance of the silica-alumina molecular sieves in the fluidized bed catalyst is significantly affected by it. Furthermore, granulated products obtained by using only commercial silica sol as a binder have poor wear resistance and exhibit obvious hollowness.

[0047] Based on this, the present invention aims to provide a novel method for preparing bifunctional microsphere catalysts, which, while avoiding the influence of added binders on the catalytic performance of the catalyst, yields catalysts with high wear resistance and suitable for catalytic CO2 catalysis. xA bifunctional microsphere catalyst for the production of aromatic chemicals / liquid fuels from H2. Specifically, nano-yttrium oxide-modified phosphate ceramic colloid, silica sol, and alumina sol are used as binders in the preparation of the fluidized bed catalyst. The use of nano-yttrium oxide-modified phosphate ceramic colloid not only facilitates the tight bonding between the alkali metal oxide and the silica-alumina molecular sieve, but also effectively reduces the amount of silica sol used, thus minimizing the impact of silica sol on the catalytic performance of the silica-alumina molecular sieve and contributing to the improvement of the catalytic performance of the bifunctional microsphere catalyst. In other words, this invention, by adjusting the content of nano-yttrium oxide-modified phosphate ceramic colloid, silica sol, and alumina sol in the preparation process of the bifunctional microsphere catalyst, ultimately obtains a catalyst for catalytic CO2 production that meets the practical application requirements in terms of both wear resistance and catalytic performance. x A bifunctional microsphere catalyst for the production of aromatic chemicals / liquid fuels using H2. Specific implementation details are as follows:

[0048] In a first aspect, the present invention provides a method for catalyzing CO. x A method for preparing bifunctional microsphere catalysts for the production of aromatic chemicals / liquid fuels using H2. Figure 1 A flowchart illustrating the preparation method of the bifunctional microsphere catalyst provided in this embodiment of the invention is shown, as follows: Figure 1 As shown, the preparation method includes the following preparation steps:

[0049] S1. After uniformly mixing the nano-yttrium oxide modified phosphate ceramic adhesive, the alkaline metal oxide, and the silica-alumina molecular sieve, the mixture is placed in a reducing atmosphere calcination furnace for calcination to obtain the first precursor; wherein, the weight ratio of the alkaline metal oxide to the silica-alumina molecular sieve is 0.1-10, and the dry basis of the nano-yttrium oxide modified phosphate ceramic adhesive accounts for 5%-30% of the total mass of the alkaline metal oxide and the silica-alumina molecular sieve;

[0050] In practical implementation, the bifunctional catalyst provided by this invention is used for fluidized bed catalysis of CO. x +H2 to produce aromatic chemicals / liquid fuels, CO in the process x The catalyst first converts the material into methanol, which is then further converted into aromatic chemicals / liquid fuels under the action of the catalyst. Therefore, in the selection of the catalyst, this invention chooses an alkaline metal oxide (used for catalyzing CO2). xThe above conversion is achieved using alkali metal oxides (converted to methanol) and silica-alumina molecular sieves (used for catalytic conversion of methanol to aromatic chemicals / liquid fuels). Specifically, the alkali metal oxides can be selected from monometallic oxides, bimetallic oxides, or metal-supported oxides with the metal spontaneously dispersed on the monometallic oxides or bimetallic oxides; the alkali metal oxides are in the form of spinel, perovskite, solid solution, or mesoporous single crystals; the silica-alumina molecular sieves can be selected from hydrogen-form silica-alumina molecular sieves, with a silica-alumina ratio of 20-200, and selected from H-ZSM5, ZSM-5, ZSM-11, or ZSM-48. The weight ratio of alkali metal oxides to silica-alumina molecular sieves can be 0.1-10.

[0051] Furthermore, in this preparation step, the nano-yttrium oxide-modified phosphate ceramic adhesive is prepared by mixing industrial phosphoric acid, aluminum hydroxide powder, silicic acid, light magnesium oxide, yttrium oxide, and water, and then heating and stirring until the solution becomes transparent. The heating temperature is controlled at 110-150℃, and the mass percentages of each raw material component are as follows: industrial phosphoric acid: 55%-58%; aluminum hydroxide powder: 11.5%-11.85%; silicic acid: 1.03%-1.05%; light magnesium oxide: 2.05%-2.06%; yttrium oxide: 0.02%-0.09%; the remainder is water. The added nano-yttrium oxide-modified phosphate ceramic adhesive accounts for 10%-30% of the total mass of the alkali metal oxide and the silica-alumina molecular sieve.

[0052] Furthermore, in this preparation step, after uniformly mixing the nano-yttrium oxide-modified phosphate ceramic adhesive, alkali metal oxide, and silica-alumina molecular sieve, the mixture is placed in a reducing atmosphere calcination furnace for calcination. During this process, the presence of yttrium oxide in the modified yttrium oxide ceramic adhesive causes the alkali metal oxide to be electrically welded to the surface of the silica-alumina molecular sieve in a "welding" manner, forming a composite catalyst (first precursor) with a tight bond between the alkali metal oxide and the silica-alumina molecular sieve, thus enhancing the overall integrity of the alkali metal oxide and the silica-alumina molecular sieve. This helps to strengthen the wear resistance of the final fluidized bed catalyst. The calcination conditions are controlled as follows: pressure in the calcination furnace is 0.5-1 MPa, hydrogen flow rate is 0.1-1000 ml / min, temperature is 150-350℃, and calcination time is 1-10 h.

[0053] In some embodiments, as a preferred example, the preferred nano-yttrium oxide modified phosphate ceramic adhesive provided by the present invention has the following composition: 338g of 85% industrial phosphoric acid, 68g of 320-mesh aluminum hydroxide powder, 6g of silica, 12g of light magnesium oxide, 0.5g of nano-yttrium oxide, and 1000g of purified water.

[0054] In some embodiments, the preferred single metal oxide is MnO. x The preferred bimetallic oxide is spinel ZnCrO. xOr perovskite-type LaFeO3; the preferred silica-alumina molecular sieve is H-ZSM5; the preferred weight ratio of alkaline metal oxide to silica-alumina molecular sieve is 1:1, and the preferred nano-yttrium oxide modified phosphate ceramic adhesive accounts for 20% of the total mass of alkaline metal oxide and silica-alumina molecular sieve.

[0055] Furthermore, the metal-supported oxide spontaneously and monodispersed on the single-metal oxide or bimetal oxide specifically has single metal atoms of Zn, Cu, Cr, Mn, Pd, Zr, Al, Mo, Ge, In, Ni, Au, Fe, or Y, uniformly supported on the single-metal oxide MnOx, bimetal oxide LaFeO3, or bimetal oxide ZnCrO in the form of chemical bonds. x The surface forms a regular atomic arrangement; the mass of a single metal atom accounts for 0.01 to 10% of the mass of the metal oxide.

[0056] S2. The first precursor is mixed evenly with binder, matrix material and deionized water to form a suspension, and then the pH is adjusted to 2.5-5.5 to make the suspension into a gel.

[0057] In this preparation process, considering that using only silica sol as a binder in large quantities would affect the catalytic performance of the catalyst, the inventors discovered during their research that adding an appropriate amount of alumina sol to commercial silica sol can significantly improve the fluidity of the suspension, reduce the hollowness of the granulated product, and improve the wear resistance of the catalyst product. Furthermore, the presence of nano-yttrium oxide-modified phosphate ceramic adhesive in the first precursor can further reduce the amount of silica sol used, avoiding the impact of large amounts of silica sol on the catalytic performance of the catalyst. That is, the binder used in this invention is actually composed of silica sol, alumina sol, and nano-yttrium oxide-modified phosphate ceramic adhesive. Since the nano-yttrium oxide-modified phosphate ceramic adhesive was already added in step S1, silica sol (as the main binder) and alumina sol (as the auxiliary binder) are added in this step. Further research revealed that adding too high a content of auxiliary binder will reduce the activity of the catalyst product and the selectivity of the target chemical, while adding too low a content of auxiliary binder will reduce the wear resistance of the catalyst product and increase the wear index. Therefore, based on multiple experiments, the embodiments of the present invention have found that when the dry basis mass ratio of silica sol to alumina sol is 1:0.01 to 0.25, the wear resistance of the catalyst and the catalytic performance of the catalyst product are both in a good state of comprehensive balance.

[0058] In specific implementation, the matrix material is selected from at least one of clay, hydrotalcite, kaolin, montmorillonite, bentonite, and saponin. In the suspension, the dry matrix ratio of the first precursor, binder, and matrix material is controlled at 10-70:10-30:20-45; the mass percentage of deionized water is controlled at 55-65%.

[0059] This invention employs a granulation method to prepare microsphere catalysts. The composite catalyst (first precursor) obtained in step 1 is mixed uniformly with a binder, matrix material, and an appropriate amount of deionized water to form a suspension. The fluidity of the suspension is adjusted to ensure it has both sufficient flowability and the ability to form solid microspheres for granulation. Therefore, in this specific implementation, after uniformly mixing the first precursor with the binder, matrix material, and deionized water to form a suspension, the pH of the suspension is adjusted to obtain a gel-like suspension with a certain degree of fluidity. Spray granulation is then performed in the gel state. Because the fluidity of the gel state is poor, the pH value of the slurry needs careful adjustment. Based on repeated experiments, this invention has determined that a pH range of 2.5–5.5 for the suspension satisfies the requirements for both fluidity and the formation of solid microspheres for granulation. Preferably, the pH of the suspension is controlled between 3.1 and 3.9. More preferably, the pH is 3.5.

[0060] In some embodiments, the dry matrix ratio of the preferred first precursor, binder, and matrix material is controlled at 25%; the mass percentage of deionized water is controlled at 70%.

[0061] S3. After high-speed shearing of the suspension, the suspension is granulated by spray granulation to obtain solid microspheres. These solid microspheres are then calcined to form the CO2. x Bifunctional microsphere catalyst for the production of aromatic chemicals / liquid fuels using H2.

[0062] In this step, the suspension after high-speed shearing is prepared into solid microspheres using spray granulation. The inlet temperature of the spray granulation tower is 350℃, and the outlet temperature is 200℃. The obtained solid microspheres are further calcined at 300-450℃ for 2-5 hours to obtain materials suitable for CO2 processing. x Bifunctional microsphere catalyst for the production of aromatic chemicals / liquid fuels using H2.

[0063] In a second aspect, the present invention provides a bifunctional microsphere catalyst obtained by the preparation method described in the first aspect above.

[0064] Thirdly, the present invention provides an application of the bifunctional microsphere catalyst obtained by the preparation method described in the first aspect above, wherein the bifunctional microsphere catalyst is used for catalytic CO2 catalysis in a fluidized bed reactor. x +H2 to produce aromatic chemicals / liquid fuels.

[0065] Furthermore, the bifunctional microsphere catalyst is used in a fluidized bed reactor to catalyze CO2 production. xThe catalytic conditions for the production of aromatic chemicals / liquid fuels from hydrogen (H2) are: temperature 270-380℃; space velocity 300-1000 mL / h·gcat; hydrogen and CO... x The volume ratio is 0.5 to 3.

[0066] To enable those skilled in the art to more clearly understand this application, the following examples illustrate the method for catalytic CO2 production described in this application. x This paper provides a detailed description of bifunctional microsphere catalysts for the production of aromatic chemicals / liquid fuels from H2, their preparation methods, and applications.

[0067] Example 1

[0068] ZnCrO x Bifunctional microsphere catalyst prepared by combining with H-ZSM5

[0069] (a) Preparation of nano-yttrium oxide modified phosphate ceramic adhesive

[0070] Add 338g of 85% industrial phosphoric acid, 68g of 320-mesh aluminum hydroxide powder, 6g of silica, 12g of light magnesium oxide, 0.5g of nano-yttrium oxide, and 1000g of purified water to a beaker in sequence. Stir and slowly heat to 150°C until the solution becomes transparent to obtain nano-yttrium oxide modified phosphate ceramic adhesive.

[0071] (b) Weigh 1122.5g of ZnCrOx spinel oxide prepared by co-precipitation and 1000g of H-ZSM5 molecular sieve and mix them evenly;

[0072] (c) Mix the components from steps (a) and (b) thoroughly and heat to 80°C until the mixture becomes gel-like. Then dry the gel component at 120°C overnight.

[0073] (d) The powder obtained in step (c) is calcined in a special high-pressure reduction calcination furnace at a pressure of 0.5 MPa and a reducing gas of hydrogen at a flow rate of 100 ml / min for 5 h.

[0074] (e) Mix 10 parts of the powder obtained in step (d) with 30 parts of the binder and an appropriate amount of water in a stirring vessel until homogeneous; the binder consists of 45% silica sol and 10% aluminum-containing hydrosol by mass, with the dry basis mass ratio of the two components in the binder being 1:0.25; then add 20 dry basis parts of kaolin to the mixed suspension and stir to obtain a suspension emulsion with a solid mass content of 35%; adjust the pH of the suspension emulsion to 3.5 to make it gel-like;

[0075] (f) The gel was granulated and dried using a spray granulation method. The inlet temperature of the granulation tower was 350℃ and the outlet temperature was 200℃ to produce solid microspheres.

[0076] (g) Solid microspheres are calcined in the range of 300-450℃ to prepare bifunctional microsphere catalysts for the production of aromatic chemicals / liquid fuels from CO2 / CO1+H2;

[0077] The reaction performance of the catalyst was evaluated using a fixed-bed microreactor. The experimental conditions were as follows: catalyst loading was 1.0 g, reaction gases were carbon dioxide and hydrogen in a volume ratio of 1:3, reaction temperature was 320 °C, reaction pressure was 3 MPa, and weight hourly space velocity was 300 ml / g·h.

[0078] Example 2

[0079] This embodiment uses Fe / ZnCrO with single-metal Fe deposition. x The bifunctional microsphere catalyst prepared by combining the catalyst with H-ZSM5, that is, compared with Example 1, the difference is that in step (b) of this example, Fe / ZnCrO with single-metal Fe placement is weighed. x The catalyst and H-ZSM5 were used, and the remaining steps were the same as in Example 1.

[0080] Fe / ZnCrO with single-metal Fe deposition x The catalyst is prepared as follows:

[0081] Step 1: Prepare a bimetallic oxide support with abundant oxygen vacancies and metal defect landing sites on its surface.

[0082] (1) Weigh 13.98g of zinc nitrate hexahydrate and 37.61g of chromium nitrate nonahydrate and dissolve them in beaker A containing 1000g of deionized water. Then place beaker A in a heatable magnetic stirrer. Heat the magnetic stirrer to 60°C and stir continuously for 60 minutes until the solid salts are completely dissolved.

[0083] (2) Prepare a beaker containing 500g of deionized water, labeled beaker B. Add 48.05g of ammonium carbonate to beaker B and place beaker B on a heated magnetic stirrer. Set the temperature to 45℃ and stir thoroughly until the solid is completely dissolved.

[0084] (3) Prepare a three-necked flask, slowly add the solutions in beaker A and beaker B into the three-necked flask, maintain the temperature of the mixed solution at 70-100℃, control the pH of the mixed solution in the three-necked flask to be between 5.5 and 8.5 by adjusting the rate of addition of the solution in beaker A or B, and keep stirring throughout the process.

[0085] (4) After mixing, continue stirring and introduce nitrogen gas to allow the mixture to crystallize under a nitrogen atmosphere for 8 hours.

[0086] (5) After crystallization in step 4, add carbon nanotubes to the mixture at a ratio of 1:0.01. At the same time, turn off the heating and continue stirring, maintaining natural cooling and stirring for 2 to 6 hours until room temperature.

[0087] (6) The obtained metal oxide precursor was subjected to three cycles of vacuum filtration and washing, dried at 110℃, and calcined at 450℃ for 2 hours in air at a rate of 5℃ / min. This yielded ZnCrO₂ with abundant oxygen vacancies and metal defect sites on its surface. x Bimetallic oxide support.

[0088] Step 2: Metal falls into place spontaneously

[0089] (1) A certain amount of ferric nitrate nonahydrate was dissolved in deionized water and reacted under microwave power of 300W for 2 min-5 min to prepare a uniformly dissolved single metal atom stock solution, wherein the mass ratio of Fe to metal oxide was 0.03:1;

[0090] (2) The ZnCrO prepared in step 1 x The bimetallic oxide support was uniformly mixed with a single-atom stock solution, and then subjected to ultrasonic treatment at a power of 600 W, a frequency of 40 kHz, and a duration of 4 h. After ultrasonication, the mixture was calcined in air at a rate of 1 °C / min to 350 °C for 2 h. This yielded Fe / ZnCrO₂ with spontaneously dissipated Fe metal. x catalyst.

[0091] Example 3

[0092] This embodiment uses ZnCrO x The bifunctional microsphere catalyst prepared by combining with commercially available ordinary ZSM5, that is, the difference from Example 1, is that in step (b) of this example, ZnCrO is weighed. x The remaining steps are the same as in Example 1, except for ZSM5.

[0093] Example 4

[0094] This embodiment uses a bifunctional microsphere catalyst prepared by combining LaFeO3 perovskite metal oxide and H-ZSM5 obtained by citric acid complexation. That is, compared with Example 1, the difference is that in step (b) of this embodiment, LaFeO3 perovskite metal oxide and H-ZSM5 are weighed, while the other steps are the same as in Example 1.

[0095] The steps for preparing LaFeO3 perovskite metal oxide using the citric acid complexation method are as follows:

[0096] 8.08 g of lanthanum nitrate hexahydrate and 7.55 g of ferric nitrate nonahydrate were added to 50 ml of deionized water at room temperature and stirred rapidly until completely dissolved. Then, 23.1 g of anhydrous citric acid was added. The solution was stirred at 550 rpm and heated to 80 °C. Ammonium carbonate solution was gradually added dropwise to adjust the pH to approximately 7. Excess liquid was evaporated, and the mixture was stirred to form a viscous gel. The gel was then removed. The gel was then dried in an oven at 110 °C for 24 hours and ground after natural cooling to obtain the LaFeO3 precursor. The dried precursor perovskite was calcined in a muffle furnace at 450 °C for 2 hours to obtain the LaFeO3 perovskite matrix.

[0097] The obtained LaFeO3 perovskite parent material was placed in a 10% reducing gas / N2 mixture and reduced at 350℃ with a pressure of 0.5 MPa and a flow rate of 300 ml / min for 2 h to obtain LaFeO3 perovskite metal oxide.

[0098] Example 5

[0099] This embodiment uses MnO x The bifunctional microsphere catalyst prepared by combining with H-ZSM5, that is, compared with Example 1, differs in that MnO is weighed in step (b) of this example. x The remaining steps are the same as in Example 1, except for H-ZSM5.

[0100] single metal oxide MnO x The preparation method is as follows:

[0101] (1) Dissolve manganese nitrate tetrahydrate in deionized water, with a mass ratio of manganese nitrate tetrahydrate to deionized water of 1:20; stir the prepared manganese nitrate solution continuously on a magnetic stirrer until fully dissolved, and heat to 70-80℃;

[0102] (2) Prepare a certain amount of ammonium acetate solution with pH 9-10, and the mass ratio of the ammonium acetate solution to the manganese nitrate solution is 1:2;

[0103] (3) Add manganese nitrate solution and ammonium acetate solution to the three-necked flask slowly at the same time, control the pH between 6 and 8, maintain the temperature of the solution in the three-necked flask at 70-80°C in a water bath, and stir vigorously throughout the process.

[0104] (4) After mixing, continue stirring and introduce nitrogen gas to allow the mixture to crystallize under a nitrogen atmosphere for 24 seconds.

[0105] (5) After crystallization in step 4, add glucose to the mixture at a ratio of 1:0.1. At the same time, turn off the heating and continue stirring, maintaining natural cooling and stirring for 2 to 6 hours until room temperature.

[0106] (6) The obtained metal oxide precursor was subjected to three cycles of vacuum filtration and washing, dried at 110℃, and calcined at 550℃ for 2 hours in air at a rate of 10℃ / min. This yielded MnO with abundant oxygen vacancies and metal defect sites on its surface. x Single metal oxides.

[0107] Comparative Example 1

[0108] The difference between this comparative example and Example 1 is that no nano-yttrium oxide modified phosphate ceramic adhesive is added. The weight component of the ceramic adhesive is supplemented by silica sol. All other implementation steps are the same as in Example 1.

[0109] Comparative Example 2

[0110] The difference between this comparative example and Example 1 is that the high-pressure reduction calcination step (d) was not performed, and the dried powder was directly subjected to the subsequent spraying step. All other implementation steps are the same as in Example 1.

[0111] The present invention uses the bifunctional microsphere catalyst prepared in Example 1 for spectral characterization, wherein, Figure 2 The XRD pattern of the bifunctional microsphere catalyst provided in the embodiments of the present invention is shown. Figure 3 This shows a scanning electron microscope image of the bifunctional microsphere catalyst provided in an embodiment of the present invention; Figure 4 The temperature-programmed reduction curve of the bifunctional microsphere catalyst provided in the embodiments of the present invention is shown. Figure 5 The image shows a scanning electron microscope (SEM) image of the bifunctional microsphere catalyst provided in this embodiment of the invention after reaction in a fluidized bed reactor. From the above images, we can see that after the addition of modified yttrium oxide ceramic adhesive and other binders, Figure 2 The XRD pattern showed that the crystal phase did not change, proving that the crystal form of the catalyst did not change after the molding process; Figure 3 The scanning electron microscope images shown demonstrate that the bifunctional microsphere catalyst is well-formed; from Figure 4 It can be seen that the addition of the colloid did not change the reduction temperature of the catalyst, indicating that the active component and the colloid did not interact. Figure 5 The results showed that the comparative catalyst was not strong enough and broke down after reaction in the fluidized bed.

[0112] Verification of the wear index

[0113] The wear index of the formed fluidized bed catalyst was determined according to standard ASTM D5757-95 using the air jet method. Specifically, a certain amount of catalyst was loaded into the wear index measuring device, and humidified air was passed at high speed through a wear tube with three small holes at the bottom, repeatedly purging the catalyst. The fine catalyst powder shed during the wear process was collected through a specific powder filter collection device. After one hour, the weight of the blown-out fine powder was weighed. A new powder filter collection device was then used, and purging continued for another three hours under the same conditions. The weight of the blown-out fine powder and the weight of the catalyst remaining in the wear tube were weighed, and the wear index of the sample was calculated using the formula.

[0114] The catalytic performance and attrition data of the bifunctional microsphere catalysts for producing aromatic chemicals / liquid fuels from CO2 / CO1+H2 prepared in Examples 1-5 and Comparative Examples 1-2 are shown in Table 1.

[0115] Table 1 Catalytic performance and wear data of bifunctional microsphere catalysts

[0116] Example Carbon dioxide conversion rate Aromatic selectivity Wear Index Example 1 30％ 80％ 1.2 Comparative Example 1 8％ 56％ 6.2 Comparative Example 2 15％ 63％ 1.9 Example 2 35％ 82％ 1.5 Example 3 28％ 66％ 1.9 Example 4 32％ 82％ 1.3 Example 5 31％ 79％ 1.8

[0117] As can be seen from the table above, the present invention prepares a catalyst for CO2 catalysis in a fluidized bed reactor. x In the process of producing bifunctional microsphere catalysts for aromatic chemicals / liquid fuels using +H2, nano-yttrium oxide-modified phosphate ceramic colloids are added. The three components—nano-yttrium oxide-modified phosphate ceramic colloids, alkaline metal oxides, and silica-alumina molecular sieves—are first calcined under a reducing atmosphere. This process can achieve a fluidized bed catalyst with improved wear resistance, aromatic selectivity, and feed conversion rate for the bifunctional microsphere catalyst.

[0118] The above describes the catalytic CO provided by this invention. x This paper provides a detailed description of a bifunctional microsphere catalyst for the production of aromatic chemicals / liquid fuels from H2, its preparation method, and its applications. Specific examples are used to illustrate the principles and implementation methods of this invention. The descriptions of the above examples are only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A process for the preparation of a bifunctional microspherical catalyst for catalyzing the conversion of CO x + H2 to aromatic chemicals, characterized in that, The preparation method comprises the following preparation steps: S1, the nano yttria modified phosphoric acid ceramic glue, the basic metal oxide and the silica alumina molecular sieve are mixed uniformly, then are placed in a reducing atmosphere calcination furnace to carry out calcination, to obtain a first precursor; wherein, the weight ratio of the basic metal oxide and the silica alumina molecular sieve is 0.1-10, and the nano yttria modified phosphoric acid ceramic glue accounts for 5%-30% of the total mass of the basic metal oxide and the silica alumina molecular sieve; S2, the first precursor is mixed with a binder, a matrix material and deionized water to form a suspension, and then the pH is adjusted to 2.5-5.5, so that the suspension becomes a gel; S3, after high-speed shearing of the suspension, the suspension is granulated by a spray granulation method to obtain solid microspheres, and the solid microspheres are calcined to form the CO x bifunctional microsphere catalyst for producing aromatic chemicals In step S1, the silica alumina molecular sieve is a hydrogen type silica alumina molecular sieve, the silica alumina ratio is 20-200, and the silica alumina molecular sieve is selected from H-ZSM5, ZSM-5, ZSM-11 or ZSM-48; The nano yttria modified phosphoric acid ceramic glue is prepared by mixing industrial phosphoric acid, aluminum hydroxide powder, silicic acid, light magnesium oxide, yttrium oxide and water under heating conditions, and the mass ratio of each raw material is: Industrial phosphoric acid: 55%-58%; Aluminum hydroxide powder: 11.5%-11.85%; Silicic acid: 1.03%-1.05%; Light magnesium oxide: 2.05%-2.06%; Yttrium oxide: 0.02%-0.09%; The rest is water; In step S2, the binder is composed of silica sol and aluminum sol, and the dry base mass ratio of the silica sol and the aluminum sol is 1:0.01-0.25; In step S3, the inlet temperature of the granulation tower for the spray granulation is 350 ℃, and the outlet temperature is 200 ℃.

2. The production method according to claim 1, characterized by, In step S1, the basic metal oxide is a single metal oxide, a double metal oxide, or a metal supported oxide in which a metal is spontaneously and monodispersed on the single metal oxide or the double metal oxide, and the form of the basic metal oxide is spinel, perovskite, solid solution or mesoporous single crystal. The calcination conditions are as follows: the pressure in the calcination furnace is controlled to be 0.5-1 Mpa, the hydrogen flow rate is 0.1-1000 ml / min, the temperature is 150-350 ℃, and the calcination time is 1-10 h.

3. The preparation method according to claim 2, characterized in that, In step S1, the monometallic oxide is MnO x , the bimetallic oxide is spinel ZnCrO x or perovskite LaFeO3; and the silicon-aluminum molecular sieve is H-ZSM.

4. The method of claim 1, wherein, In step S1, the weight ratio of the basic metal oxide and the silica alumina molecular sieve is 1:1, and the nano yttria modified phosphoric acid ceramic glue accounts for 20% of the total mass of the basic metal oxide and the silica alumina molecular sieve.

5. The preparation method according to claim 1, characterized in that, In step S2, the matrix material is selected from at least one of hydrotalcite, kaolin, montmorillonite, bentonite and bentonite; In the suspension, the dry base ratio of the first precursor, the binder and the matrix material is 10-70:10-30:20-45, and the mass ratio of the deionized water is 55-65%.

6. The method of claim 1, wherein, In step S3, the calcination temperature is 300-450 ℃.

7. A bifunctional microspherical catalyst obtained by the preparation method of any one of claims 1-6.

8. Use of the bifunctional microspherical catalyst obtained by the production process according to any one of claims 1 to 6, characterized in that, The bifunctional microspheres catalyst is used for catalyzing CO x +H2 into aromatic chemicals in a fluidized bed reactor.

9. Use according to claim 8, characterized in that, The bifunctional microspheres catalyst is used in a fluidized bed reactor to catalyze the production of aromatic chemicals from CO x +H2 under the following catalytic conditions: The temperature is 270-380 ℃; The space velocity is 300-1000 mL / h•gcat; hydrogen and CO x 0.5 to 3 in volume ratio.

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