Sulfur-tolerant shift catalyst carrier and preparation method thereof

Abstract

The invention provides a sulfur-tolerant shift catalyst carrier and a preparation method thereof, and belongs to the field of catalyst carriers. The method comprises the following steps: obtaining an organic alcohol water solution with a set mass concentration; the organic alcohol aqueous solution and rho-Al2O3 powder are molded, and green pellets are obtained; and sequentially curing and roasting the green pellets to obtain the sulfur-tolerant shift catalyst carrier. The organic alcohol aqueous solution and the rho-Al2O3 powder are formed, on one hand, organic alcohol molecules existing among rho-Al2O3 powder particles are decomposed into CO2 and H2O in the roasting process to be completely volatilized, so that a loose and porous structure is formed, and the bulk density is reduced; on the other hand, compared with traditional plant straw fine powder, the organic alcohol aqueous solution simplifies the production process, and meanwhile, the problem that the plant straw fine powder is difficult to purchase is avoided, so that the bulk ratio of the sulfur-tolerant shift catalyst carrier is reduced, and meanwhile, the production cost is reduced.

Description

Technical Field

[0001] This application relates to the technical field of catalyst carriers, and particularly relates to a sulfur-tolerant shift catalyst carrier and a preparation method thereof. Background Art

[0002] Spherical carriers of wide-temperature sulfur-tolerant shift catalysts mainly use inorganic oxide materials such as alumina. These materials have a large specific surface area, good pore structure and chemical stability, which are beneficial to the dispersion of active components and the progress of catalytic reactions. Spherical carriers of wide-temperature sulfur-tolerant shift catalysts are widely used in industrial fields such as ammonia synthesis and hydrogen production.

[0003] The most significant indicators required for spherical carriers of wide-temperature sulfur-tolerant shift catalysts are that the bulk density of the product is lower than 0.5 g / mL and the average strength is greater than 60 N / particle. Before the 1990s, this kind of carrier was produced by doping a certain proportion of sesbania powder into ρ-Al2O3 powder, then spraying water in a granulating disk for shaping, and going through processes such as preliminary ripening, ripening, and calcination. In 1994, the Shandong Aluminum Research Institute used finely ground plant straw (residue less than 5% after passing through a 325-mesh sieve) as an additive. After mixing with ρ-Al2O3 powder, it was sprayed with water in a granulating disk for shaping, and successfully produced carrier balls that met the requirements. The production cost was further reduced, and it was well received by manufacturers using sulfur-tolerant shift catalyst carriers. However, in the production method of spraying water in the granulating disk, the particle size of the finely ground plant straw, the mixing uniformity, the shaping process, etc. all have a fatal impact on the stability of "bulk density", one of the most critical indicators of the product. At the same time, with the upgrading of environmental protection and other work, there are fewer and fewer enterprises processing finely ground plant straw or corn cob, the price remains high, and it is difficult to ensure timely supply. Therefore, how to reduce the bulk density of the sulfur-tolerant shift catalyst carrier while reducing the production cost and ensuring the raw material supply is a technical problem that needs to be solved urgently at present. Summary of the Invention

[0004] This application provides a sulfur-tolerant shift catalyst carrier and a preparation method thereof to solve the following technical problems: how to reduce the bulk density of the sulfur-tolerant shift catalyst carrier while reducing the production cost.

[0005] In a first aspect, this application provides a preparation method of a sulfur-tolerant shift catalyst carrier, and the method includes:

[0006] Obtaining an organic alcohol aqueous solution with a set mass concentration;

[0007] Shaping the organic alcohol aqueous solution and ρ-Al2O3 powder to obtain green balls; and

[0008] Successively ripening and calcining the green balls to obtain a sulfur-tolerant shift catalyst carrier.

[0009] Optionally, the organic alcohol in the organic alcohol aqueous solution is polyvinyl alcohol.

[0010] Optionally, the mass concentration of the polyvinyl alcohol is 0.15‰ to 0.3‰.

[0011] Optionally, the granulation is performed using a granulation disk. The forming of the organic alcohol aqueous solution and ρ-Al2O3 powder includes:

[0012] Adjust the rotation direction of the granulation disk to counterclockwise;

[0013] Adjust the inclination angle of the granulation disk to a set inclination angle;

[0014] Adjust the rotation speed of the granulation disk to a set rotation speed;

[0015] Adjust the feeding speed of the granulation disk to a set feeding speed;

[0016] Adjust the water spraying amount of the atomizing nozzle of the granulation disk to a set water spraying amount; and

[0017] Under set conditions, after there is ρ-Al2O3 powder in the granulation disk, atomize and spray the organic alcohol aqueous solution onto the surface of the ρ-Al2O3 powder to form the organic alcohol aqueous solution and ρ-Al2O3 powder.

[0018] Optionally, the set inclination angle is 42° to 43°; and / or,

[0019] The set rotation speed is 23 Hz to 25 Hz.

[0020] Optionally, the set feeding speed is 17.5 kg / m to 18.5 kg / m.

[0021] Optionally, the set water spraying amount is 7.4 L / m to 8 L / m.

[0022] Optionally, the environmental temperature for curing is > 25 °C, and the curing time is ≥ 24 h.

[0023] Optionally, the calcination temperature is 530 °C to 570 °C, and the calcination time is 2.5 h to 3.5 h.

[0024] In a second aspect, the present application provides a sulfur-resistant shift catalyst carrier prepared by the method according to any one of the embodiments in the first aspect. The sulfur-resistant shift catalyst carrier satisfies at least one of the following performances:

[0025] The bulk density ≤ 0.51 g / mL;

[0026] The average strength > 60 N / grain;

[0027] The specific surface area is 200 m 2 / g to 240 m 2 / g;

[0028] The pore volume is 0.46 mL / g to 0.50 mL / g.

[0029] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0030] The embodiment of the present application provides a preparation method of a sulfur-tolerant shift catalyst support, the method includes: obtaining an organic alcohol aqueous solution with a set mass concentration; shaping the organic alcohol aqueous solution and ρ-Al2O3 powder to obtain green balls; and successively aging and roasting the green balls to obtain a sulfur-tolerant shift catalyst support. By shaping the organic alcohol aqueous solution and ρ-Al2O3 powder, on the one hand, the water therein undergoes a hydration reaction with the ρ-Al2O3 powder and is transformed into crystal water, and the organic alcohol molecules existing between the ρ-Al2O3 powder particles decompose into CO2 and H2O during the roasting process, and the organic alcohol can completely volatilize, thereby forming a porous structure to achieve the purpose of reducing the bulk specific gravity of the product. On the other hand, compared with the traditional fine powder of plant straw, the organic alcohol aqueous solution simplifies the production processes of batching and mixing, and at the same time avoids the problem that it is difficult to purchase the fine powder of plant straw. Thus, while reducing the bulk specific gravity of the sulfur-tolerant shift catalyst support, the production cost is reduced and the production organization is facilitated. Description of the Drawings

[0031] The drawings here are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0033] Figure 1 It is a schematic flow chart of a preparation method of a sulfur-tolerant shift catalyst support provided by the embodiment of the present application;

[0034] Figure 2 It is a physical diagram of a granulating disk during the preparation of a sulfur-tolerant shift catalyst support provided by Embodiment 1 of the present application;

[0035] Figure 3 It is a 10-μm electron micrograph of a sulfur-tolerant shift catalyst support provided by Embodiment 1 of the present application;

[0036] Figure 4 It is a 10-μm electron micrograph of activated aluminum balls produced by a conventional method. Detailed Embodiments

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts belong to the scope protected by this application.

[0038] The various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be construed as a rigid limitation on the scope of this application; therefore, it should be considered that the described range description has specifically disclosed all possible sub-ranges and single values within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any cited number (fraction or integer) within the indicated range.

[0039] In addition, in the description of the specification of the present application, terms such as "include" and "comprise" mean "including but not limited to". In this text, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In this text, "and / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. Where A and B can be singular or plural. In this text, "at least one" means one or more, and "a plurality" means two or more. "At least one kind", "at least one item (piece) below" or similar expressions refer to any combination of these items, including any combination of single item (piece) or plural items (pieces). For example, "at least one item (piece) among a, b, or c", or, "at least one item (piece) among a, b, and c" can both mean: a, b, c, a - b (i.e., a and b), a - c, b - c, or a - b - c, where a, b, and c can be single or multiple respectively. The "parts representation method" such as weight parts and mass parts represents the proportional relationship between each component. In the proportional relationships involved in this text, the parameters that need to be described by proportion should be understood as the antecedents of the proportion formula in the order of description, and the proportional numbers should be understood as the consequents of the proportion formula. For example, if the mass ratio of substance A, substance B, and substance C is 1:2:3, then substance A, substance B, and substance C should correspond one by one with the proportional numbers in the proportion formula in the order of description, that is, the mass of substance A: the mass of substance B: the mass of substance C = 1:2:3.

[0040] Unless otherwise specifically stated, various raw materials, reagents, instruments, and equipment used in the present application can be obtained through market purchases or can be prepared by existing methods.

[0041] Figure 1 It is a schematic flow chart of a preparation method of a sulfur - tolerant shift catalyst support provided for the embodiments of the present application.

[0042] As Figure 1 shown, the present application provides a preparation method of a sulfur - tolerant shift catalyst support, and the method includes:

[0043] S1. Obtain an aqueous organic alcohol solution with a set mass concentration;

[0044] In some embodiments, the organic alcohol in the aqueous organic alcohol solution is polyvinyl alcohol.

[0045] In some embodiments, obtaining an aqueous organic alcohol solution with a set mass concentration specifically includes:

[0046] Dissolve the organic alcohol in water at a set temperature, where the set temperature > 90 °C, to obtain a mixed solution;

[0047] Add water into the forming tank;

[0048] Transfer the mixed solution into the forming tank to obtain an aqueous solution of organic alcohol with a set mass concentration; the temperature of the aqueous solution of organic alcohol > 25 °C, and a stirring component is provided in the forming tank.

[0049] The water temperature is related to the solubility of the organic alcohol. Limiting the set temperature > 90 °C is beneficial to the dissolution of the organic alcohol. According to multiple dissolution tests, every 180 L of water at about 95 °C can dissolve at most 5 kg. If more is added, the solution becomes more viscous and is not easy to discharge. After polyvinyl alcohol is dissolved, it is a milky white viscous liquid with dense small bubbles. After standing and cooling, it becomes a transparent viscous liquid. Limiting the temperature of the aqueous solution of organic alcohol in the forming tank > 25 °C and continuously stirring can avoid clogging the spray gun.

[0050] In the embodiments of the present application, soluble organic matter is selected, and a solvent with a suitable ratio is prepared. Direct forming by spraying the solution is the preferred technical route. After multiple rounds of tests (used in specific production), the embodiments of the present application finally select polyvinyl alcohol as the forming solvent to prepare an organic matter solution for the production of this wide-temperature sulfur-tolerant shift catalyst spherical carrier. After forming with a polyvinyl alcohol solution, the water therein undergoes a hydration reaction with ρ-Al2O3 powder and turns into crystal water. The organic alcohol molecules between the ρ-Al2O3 powder particles decompose into CO2 and H2O and volatilize during the calcination process, thus forming a porous structure to achieve the purpose of reducing the bulk specific gravity of the product.

[0051] In some embodiments, the mass concentration of the polyvinyl alcohol is 0.15‰ - 0.3‰.

[0052] Limiting the mass concentration of polyvinyl alcohol to 0.15‰ - 0.3‰ is beneficial to forming a porous structure to achieve the purpose of reducing the bulk specific gravity of the product. When the content of polyvinyl alcohol exceeds 0.3‰, the high concentration of polyvinyl alcohol increases the viscosity of the solution, and the solution cannot be normally atomized, resulting in frequent interruption of the forming process and seriously affecting production. Exemplarily, the mass concentration of polyvinyl alcohol is 0.15‰, 0.16‰, 0.18‰, 0.20‰, 0.22‰, 0.24‰, 0.28‰, 0.3‰, etc.

[0053] S2. Form the aqueous solution of organic alcohol and ρ-Al2O3 powder to obtain green balls; and

[0054] In some embodiments, the forming uses a granulating pan, and the forming of the aqueous solution of organic alcohol and ρ-Al2O3 powder includes:

[0055] Adjust the rotation direction of the granulation disc to counterclockwise;

[0056] Adjust the inclination angle of the granulation disc to the set inclination angle;

[0057] Adjust the rotation speed of the granulation disc to the set rotation speed;

[0058] Adjust the feeding speed of the granulation disc to the set feeding speed;

[0059] Adjust the water spraying amount of the atomizing nozzle of the granulation disc to the set water spraying amount; and

[0060] Under the set conditions, after there is ρ-Al2O3 powder in the granulation disc, atomize and spray the organic alcohol aqueous solution onto the surface of the ρ-Al2O3 powder to form a shape with the organic alcohol aqueous solution and the ρ-Al2O3 powder.

[0061] The granulation disc, also known as the pelletizing disc, is a shallow-bottomed rotating disc with an inclination angle, mainly used to press loose powdery materials into agglomerates with a certain geometric shape. The working principle of the granulation disc is mainly based on the action of the rotating disc and centrifugal force. During operation, the disc inside the equipment rotates at a certain speed, and the raw materials are evenly fed onto the disc through the feeding device. Under the high-speed rotation of the disc, the raw materials are affected by the centrifugal force and gradually move towards the edge of the disc and accumulate into a material layer with a certain thickness. At the same time, during the rolling, friction, and collision of the raw materials on the disc, particles are gradually formed. According to needs, a suitable binder, such as water or other binder solutions, should be sprayed during the rolling, friction, and collision of the raw materials on the disc to enhance the strength and stability of the particles. Finally, the formed particles slide off from the edge of the disc and are discharged through the discharging device for subsequent ripening, roasting, etc.

[0062] In some embodiments, the set inclination angle is 42° - 43°; and / or,

[0063] The set rotation speed is 23 Hz - 25 Hz.

[0064] The normal pelletizing inclination angle of the granulation disc is 45°. When producing low bulk ratio balls, appropriately reduce the inclination angle of the granulation disc, which can reduce the extrusion force on the balls in the granulation disc during growth, thereby reducing the bulk ratio. Limiting the rotation speed to 23 Hz - 25 Hz can balance the rolling times and rolling speed of the materials in the disc, help the materials roll evenly in the disc and gradually grow into balls, and at the same time avoid over-compaction and excessive extrusion force, thereby optimizing the particle formation process and reducing the bulk ratio. Exemplarily, the inclination angle can be 43°, 43.1°, 43.2°, 43.4°, 43.6°, 43.8°, 44°, etc., and the rotation speed can be 23 Hz, 23.2 Hz, 23.5 Hz, 24 Hz, 24.5 Hz, 25 Hz, etc.

[0065] In some embodiments, the set feeding speed is 17.5 kg / m to 18.5 kg / m.

[0066] By adjusting the feeding screw frequency of the granulation disc, the feeding speed of the granulation disc is controlled to be 17.5 kg / m to 18.5 kg / m. With a moderate feeding speed, the materials can be evenly distributed on the granulation disc, so that the extrusion force and frictional force received by the spheres during growth are moderate, which is conducive to forming a smooth and uniform sphere surface. At the same time, it can ensure sufficient friction and collision between the spheres and between the spheres and the disc wall, which helps the spheres to remain dispersed during the growth process and avoid adhesion and agglomeration. Exemplarily, the feeding speed can be 17.5 kg / m, 17.6 kg / m, 17.8 kg / m, 18 kg / m, 18.2 kg / m, 18.4 kg / m, 18.5 kg / m, etc.

[0067] In some embodiments, the set water spraying amount is 7.4 L / m to 8 L / m.

[0068] According to the feeding amount of the feeding screw, the water spraying amount of the atomizing nozzle is determined. If the water spraying amount of the atomizing nozzle is higher than 8 L / m, it is easy to adhere and the bulk specific gravity of the final product is too high. If the water spraying amount of the atomizing nozzle is lower than 7.4 L / m, the surface of the made balls is not smooth. Exemplarily, the water spraying amount of the atomizing nozzle can be 7.4 L / m, 7.5 L / m, 7.6 L / m, 7.7 L / m, 7.8 L / m, 7.9 L / m, 8 L / m, etc.

[0069] S3. Subject the green balls to aging and roasting in sequence to obtain a sulfur-tolerant shift catalyst support.

[0070] In some embodiments, the ambient temperature for aging is > 25 °C, and the aging time is ≥ 24 h.

[0071] By defining that the ambient temperature for aging is > 25 °C and the aging time is ≥ 24 h, it is ensured that the moisture and organic substances inside the green balls can be fully converted. The moisture therein undergoes a hydration reaction with ρ-Al2O3 powder and turns into crystal water. Exemplarily, the ambient temperature for aging can be 25.5 °C, 26 °C, 26.5 °C, 27 °C, 28 °C, etc., and the aging time can be 24 h, 25 h, 26 h, 27 h, 28 h, etc.

[0072] In some embodiments, the roasting temperature is 530 °C to 570 °C, and the roasting time is 2.5 h to 3.5 h.

[0073] The temperature of roasting is limited to 530°C to 570°C, and the roasting time is 2.5h to 3.5h, so as to ensure that the organic matter in the green balls can be completely burned, and at the same time, the inorganic components such as alumina undergo polymorphic transformation to form a stable carrier structure. Exemplarily, the roasting temperature can be 530°C, 540°C, 550°C, 560°C, 565°C, 570°C, etc., and the roasting time can be 2.5h, 2.6h, 2.8h, 3.0h, 3.2h, 3.4h, 3.5h, etc.

[0074] In the embodiments of the present application, by using the combination of an organic alcohol aqueous solution and ρ-Al2O3 powder, and through steps such as forming, curing, and roasting, compared with the traditional method using fine plant straw powder, significant advantages in many aspects are shown, as follows:

[0075] I. Advantages of raw materials

[0076] (1) Solve the procurement problem: The fine plant straw powder used in the traditional method is difficult to procure due to factors such as region, season, and environmental protection, and its price fluctuates greatly. This method uses organic alcohol, which, as a common chemical raw material, has stable supply, is easy to procure, and has a relatively stable price. (2) Storage safety: The fine plant straw powder is flammable and explosive, and there are serious fire hazards during storage. Organic alcohol does not have such problems and has higher storage safety.

[0077] II. Simplification of the production process

[0078] (1) Simplify steps: The traditional method requires complex steps such as mixing and conveying, and requires special personnel to prepare materials at any time. In this method, the organic alcohol and ρ-Al2O3 powder do not need to be mixed, and can be directly formed after preparing the solution, and the steps are more concise. (2) Reduce personnel and equipment occupancy: The traditional method requires more personnel to participate in steps such as mixing and conveying materials, and the equipment occupancy rate is high.

[0079] Due to the simplified steps of this method, the required personnel and equipment are both significantly reduced, improving the production efficiency.

[0080] III. Cost reduction

[0081] (1) Raw material cost: The price of the fine plant straw powder is affected by various factors, and the cost fluctuates greatly. Organic alcohol, as a common chemical raw material, has a relatively stable price, which is conducive to reducing production costs.

[0082] (2) Labor cost: The traditional method requires special personnel to prepare materials at any time and convey the materials into the pelletizer bin, increasing the labor cost. Due to the simplified steps of this method, preparing the solution once can complete the production of dozens of tons of products, reducing the labor demand and lowering the labor cost.

[0083] IV. Improvement of product quality

[0084] (1) Mixing uniformity: In traditional methods, due to the different specific gravities of the fine powder of plant straw and ρ-Al2O3 powder, it is not easy to mix them evenly, and they are prone to stratification during the process of being transported into the hopper of the pelletizing machine, which may lead to fluctuations in product quality. This method ensures the full contact and uniform distribution of ρ-Al2O3 powder and the forming medium through the uniform mixing of the organic alcohol aqueous solution, improving the stability of product quality. (2) No ash residue: Using the fine powder of plant straw as the raw material, ash is likely to remain in the catalyst carrier after calcination, affecting the product performance. The organic alcohol in this method burns completely without leaving any ash residue, ensuring the purity and performance of the product.

[0085] V. Environmentally friendly and pollution-free

[0086] (1) Environmental friendliness: Environmental pollution may be caused during the treatment process of the fine powder of plant straw in traditional methods. After the organic alcohol in this method is formed, the water in it undergoes a hydration reaction with ρ-Al2O3 powder. The organic alcohol between the ρ-Al2O3 powder particles decomposes into CO2 and H2O and volatilizes during the calcination process at a temperature higher than 530 °C, without causing any environmental pollution, meeting the environmental protection requirements.

[0087] VI. Good market application effect

[0088] (1) Large-scale production: This method has produced more than 600 tons of products for the market, proving the feasibility and stability of its large-scale production. (2) Application evaluation: The market application evaluation shows good results, proving the advantages of this method in terms of product quality, performance, and environmental friendliness.

[0089] In summary, the preparation method of this sulfur-tolerant shift catalyst carrier has shown significant advantages in terms of raw materials, production process, cost, product quality, environmental friendliness, and market application. This method not only solves many problems of traditional methods, but also improves production efficiency, reduces costs, enhances product quality, and meets environmental protection requirements, with broad market application prospects.

[0090] Based on a general inventive concept, this application provides a sulfur-tolerant shift catalyst carrier prepared by the method described in any one of the above embodiments, and the sulfur-tolerant shift catalyst carrier satisfies at least one of the following performances:

[0091] Bulk ratio ≤ 0.51 g / mL;

[0092] Average strength > 60 N / piece;

[0093] Specific surface area is 200 m 2 / g - 240 m 2 / g;

[0094] Pore volume is 0.46 mL / g - 0.51 mL / g.

[0095] This product is mainly used as a carrier for sulfur-tolerant shift catalysts. Sulfur-tolerant shift catalysts are essential catalysts in the synthetic ammonia and petrochemical industries, with an annual consumption of over 5,000 tons. This product can also be used as a dechlorination agent after being soaked in sodium hydroxide solution and dried. It is an essential catalyst carrier in the current chemical industry.

[0096] This sulfur-tolerant shift catalyst carrier is realized based on the above-mentioned preparation method of the sulfur-tolerant shift catalyst carrier. The specific steps of the preparation method of the sulfur-tolerant shift catalyst carrier can refer to the above-mentioned embodiments. Since this sulfur-tolerant shift catalyst carrier adopts some or all of the technical solutions of the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, and will not be elaborated one by one here.

[0097] The following will further elaborate on this application in combination with specific embodiments. It should be understood that these embodiments are only used to illustrate this application and not to limit the scope of this application. For the experimental methods without specific conditions noted in the following embodiments, they are usually determined according to industry standards. If there is no corresponding industry standard, they are carried out according to general international standards, conventional conditions, or the conditions recommended by the manufacturer.

[0098] Example 1

[0099] A preparation method of a sulfur-tolerant shift catalyst carrier provided in this example may include the following steps:

[0100] Step 1: Add tap water at room temperature (temperature > 25°C) to the molding water tank, control the water volume, calculate the required polyvinyl alcohol according to a ratio of 0.15‰, and prepare it. Prepare a container that can withstand a temperature of 100°C and has a volume of about 200L. The container is equipped with an electric stirrer and a drain valve at the bottom. Inject 180L of hot water into the container, requiring the water temperature to be greater than 90°C (normal temperature water can be injected and then heated with electric heating or steam equipment, etc.). Heat and dissolve. When the water temperature in the tank rises above 95°C, slowly add polyvinyl alcohol under the condition of stirring operation. When there are lumps in the polyvinyl alcohol, break them up and add them. After dissolution, it is a milky white viscous liquid with dense small bubbles. After standing and cooling, it becomes a transparent viscous liquid, obtaining a polyvinyl alcohol mixed solution with a mass concentration of about 3%.

[0101] Step 2: Lift the container containing the prepared polyvinyl alcohol solution above the molding water tank, open the drain valve to put the prepared solution into the molding water tank. The molding water tank needs to be equipped with a stirrer and keep it running throughout until the polyvinyl alcohol mixed solution in the water tank is used up, obtaining an aqueous polyvinyl alcohol solution with a mass concentration of 0.15‰ in the molding water tank, and the temperature of the aqueous polyvinyl alcohol solution in the molding water tank > 25°C.

[0102] Step 3: Use a granulating disk with a diameter of φ1.6 m, and adjust the rotation direction of the granulating disk to counterclockwise (adjust according to the position of the receiving chute of the granulating disk). The physical diagram of the granulating disk is as shown in Figure 2 shown.

[0103] Step 4: Adjust the inclination angle of the granulating disk to 43° and the rotation speed to 24 Hz.

[0104] Step 5: Adjust the feeding screw frequency of the granulating disk to make its feeding speed 18 kg / m.

[0105] Step 6: Adjust the water spraying amount of the atomizing nozzles of the granulating disk to 7.7 L / m. Under the condition of a fixed water supply pressure of 0.45 MPa, it can be achieved by increasing or decreasing the nozzles. In this embodiment, 7 spray guns and 7 atomizing nozzles are actually used.

[0106] Step 7: After the solution preparation and the adjustment of the granulating disk angle, rotation speed, feeding speed, and nozzle water spraying amount are in place, start the feeding screw of the granulating disk. After there is ρ-Al2O3 powder in the granulating disk, turn on the atomizing spray guns to start forming. When starting to form, seeds (seed balls ≤ 1 mm) need to be made. At this time, about 3 spray guns can be turned on. Control the number of seed balls in the granulating disk by finely adjusting (1 - 10 cm) the position of the spray guns (the distance from the spiral feeding position) or the spraying angle of the nozzles. When the number of seed balls in the granulating disk reaches 50% of the disk volume, adjust the position or angle of the spray guns to reduce the generation of seed balls and promote the gradual growth of the seed balls. During the gradual growth of the seed balls, the number of spray guns needs to be gradually increased according to the amount and dry-wet condition of the materials in the granulating disk (with the criterion that the spherical particles in the granulating disk do not stick to each other) until all 7 spray guns are fully open. If the spherical particles (hereinafter referred to as green balls) in the granulating disk do not reach the required particle size but fill the granulating disk, a certain amount of green balls need to be dug out manually with a dustpan so that the green balls in the disk can continue to grow to the required particle size. The dug-out green balls that do not reach the required particle size can be gradually filled back into the granulating disk with a dustpan during the entire forming process. If the green balls in the granulating disk have grown to the required particle size before the granulating disk is full, the green balls that reach the required particle size also need to be dug out manually and placed in a prepared large bag or hopper. When the granulating disk is full of green balls, the balls can be formed by the method of automatically throwing the balls into the receiving chute. To determine whether the green balls in the granulating disk reach the required particle size, a standard sieve needs to be prepared at the forming site so that the forming worker can screen and measure the green balls in the granulating disk at any time. Every 30 minutes when the granulating disk rotates, the forming worker needs to use special forming tools to clean the bottom and side of the disk. This step needs to strictly follow the operating procedures. For some granulating disks equipped with disk cleaning robots, the cleaning can be completed by the robot.

[0107] Step 8: The green balls in Step 7 are sealed and cured in a ton bag for 24 hours (ambient temperature > 25°C), and then roasted into finished products in a vertical furnace. The inlet temperature of the roasting furnace is set at 600 ± 20°C, the temperature in the furnace is controlled at 550 ± 20°C, and the roasting time is 2.5 - 3 h to obtain a sulfur-tolerant shift catalyst support. The 10-μm electron micrograph of the sulfur-tolerant shift catalyst support provided in Example 1 is as shown in Figure 3 shown.

[0108] Example 2

[0109] Based on the disclosure of Example 1, the following modifications are made in this example:

[0110] An aqueous solution of polyvinyl alcohol with a mass concentration of about 0.20‰ is obtained in the forming water tank.

[0111] Example 3

[0112] Based on the disclosure of Example 1, the following modifications are made in this example:

[0113] An aqueous solution of polyvinyl alcohol with a mass concentration of 0.30‰ is obtained in the forming water tank.

[0114] Example 4

[0115] Based on the disclosure of Example 1, the following modifications are made in this example:

[0116] The inclination angle of the granulating disc is 44°.

[0117] Comparative Example 1

[0118] Based on the disclosure of Example 1, the following modifications are made in this comparative example:

[0119] An aqueous solution of polyvinyl alcohol with a mass concentration of 0.10‰ is obtained in the forming water tank.

[0120] Comparative Example 2

[0121] Based on the disclosure of Example 1, the following modifications are made in this comparative example:

[0122] The inclination angle of the granulating disc is 45°.

[0123] Comparative Example 3

[0124] Based on the disclosure of Example 1, the following modifications are made in this comparative example:

[0125] The feeding speed is 15 kg / m.

[0126] Comparative Example 4

[0127] Based on the disclosure of Example 1, the following modifications are made in this comparative example:

[0128] The water spraying amount of the atomizing nozzle is 9 L / m.

[0129] The performance of the sulfur-tolerant shift catalyst supports obtained in Examples 1 to 4 and Comparative Examples 1 to 4 was measured, and the results are shown in Table 1.

[0130] Table 1 Performance of the sulfur-tolerant shift catalyst supports in Examples 1 to 4 and Comparative Examples 1 to 4

[0131]

[0132] As can be seen from Table 1, adjusting the concentration of the organic alcohol will affect the bulk density of the product, and the higher the concentration, the lower the bulk density; it will reduce the strength of the product, and the higher the concentration, the lower the strength, and even the surface of the sphere becomes extremely rough. Changing the angle of the pelletizing disk, increasing it will significantly increase the bulk density of the sphere, and decreasing it will cause a decrease; changing the water supply and feed rate will basically have no significant impact within a range of 10%. If this range is exceeded, when the feed is large (relatively less water), the strength of the product will significantly decrease and the abrasion will significantly increase (by about 0.3 - 0.5%). When the water is large (relatively), the most serious problem is that the surface of the sphere is not smooth and there are protrusions. Secondly, the bulk density will increase by 0.01 - 0.03%, and the specific surface area will decrease by about 10%, but the strength of the product will increase by more than 10%.

[0133] In addition, one or more technical solutions in the embodiments of the present application at least further have the following technical effects or advantages:

[0134] In the embodiments of the present application, the problems of difficult procurement and storage of ultrafine plant straw powder (plant straw powder is flammable and explosive after being powdered, posing a serious fire hazard), and easy uneven mixing are eliminated, and the problem of requiring a special person to prepare the ingredients at any time is also eliminated. After the organic alcohol solution is formed, the water in it undergoes a hydration reaction with the ρ-Al2O3 powder, and the organic alcohol molecules between the ρ-Al2O3 powder particles decompose into CO2 and H2O and volatilize during the calcination process, without causing any environmental pollution. It is a simple, environmentally friendly and low-cost production method for the spherical support of the sulfur-tolerant shift catalyst with a wide temperature range.

[0135] In the embodiments of the present application, the bulk density of the sulfur-tolerant shift catalyst support product is <0.50 g / ml, and can reach as low as 0.46 g / ml at the lowest; the strength of the product is increased by >10% compared with other methods; the specific surface area of the product is increased by more than 10% compared with other methods.

[0136] The above are only specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A preparation method of a sulfur-tolerant shift catalyst support, the method comprising: Obtaining an aqueous organic alcohol solution with a set mass concentration; Molding the aqueous organic alcohol solution and ρ-Al2O3 powder to obtain green pellets; and Successively aging and calcining the green pellets to obtain a sulfur-tolerant shift catalyst support.

2. The method according to claim 1, characterized in that, The organic alcohol in the aqueous organic alcohol solution is polyvinyl alcohol.

3. The method according to claim 2, wherein The mass concentration of the polyvinyl alcohol is 0.15‰ to 0.3‰.

4. The method according to claim 1, wherein The molding uses a granulating disk, and the molding of the aqueous organic alcohol solution and ρ-Al2O3 powder includes: Adjusting the rotation direction of the granulating disk to counterclockwise; Adjusting the inclination angle of the granulating disk to a set inclination angle; Adjusting the rotation speed of the granulating disk to a set rotation speed; Adjusting the feeding speed of the granulating disk to a set feeding speed; Adjusting the water spraying amount of the atomizing nozzle of the granulating disk to a set water spraying amount; and Under set conditions, after there is ρ-Al2O3 powder in the granulating disk, atomizing and spraying the aqueous organic alcohol solution onto the surface of the ρ-Al2O3 powder to form the aqueous organic alcohol solution and ρ-Al2O3 powder.

5. The method according to claim 4, wherein The set inclination angle is 42° to 43°; and / or, The set rotation speed is 23 Hz to 25 Hz.

6. The method according to claim 4, wherein The set feeding speed is 17.5 kg / m to 18.5 kg / m.

7. The method according to claim 4, characterized in that, The set water spraying amount is 7.4 L / m to 8 L / m.

8. The method according to claim 1, wherein The environmental temperature for aging is >25°C, and the aging time is ≥24 h.

9. The method according to claim 1, wherein The calcination temperature is 530°C to 570°C, and the calcination time is 2.5 h to 3.5 h.

10. A sulfur-tolerant shift catalyst support prepared by the method according to any one of claims 1 to 9, the sulfur-tolerant shift catalyst support satisfying at least one of the following properties: The bulk ratio ≤ 0.51 g / mL; The average strength > 60 N / grain; The specific surface area is 200 m 2 / g to 240 m 2 / g; The pore volume is 0.46 mL / g to 0.50 mL / g.

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