Honeycomb ceramic carrier and preparation method and application thereof

Abstract

The invention provides a honeycomb ceramic carrier as well as a preparation method and application thereof. The honeycomb ceramic carrier comprises a plurality of silicon carbide ceramic unit bodies and a plurality of hole blocking parts, wherein the hole blocking parts are prepared by sintering raw materials containing silicon carbide, aluminum oxide, strontium carbonate, metal silicon and additives; wherein the ratio of the bending strength of the axis A of the ceramic unit body to the bending strength of the hole blocking part is 1: (0.8-1.9), the bending strength of the axis A of the ceramic unit body ranges from 2.5 MPa to 38.5 MPa, and the bending strength of the hole blocking part ranges from 3 MPa to 35 MPa. According to the scheme provided by the invention, it is ensured that the bending strength of the carrier and the bending strength of the ceramic unit body have a higher matching degree, so that the yield of the carrier is improved while it is ensured that the carrier has excellent performance.

Description

Technical Field

[0001] This invention relates to the field of cellular ceramic technology, specifically to a cellular ceramic carrier, its preparation method, and its application. Background Technology

[0002] Honeycomb ceramics, particularly structures made of silicon carbide (SiC) ceramic materials, have wide applications in modern industry. These structures play a crucial role in various devices such as internal combustion engines, boilers, chemical reaction equipment, and fuel cell reformers. Their primary functions are as catalyst supports, utilizing their catalytic action, and as particulate matter collection during exhaust gas treatment, such as capturing particulate matter (PM) in diesel engine exhaust. These ceramic honeycomb structures are commonly used as diesel particulate filters (DPFs), forming a wall-flow filter by separating the individual chambers through their unique septum design.

[0003] Wall-flow honeycomb ceramics require staggered plugging to achieve the desired effect. The performance of the plugging material significantly impacts the honeycomb ceramic. Current technologies primarily focus on matching the thermal expansion coefficient of the plugging material with that of the honeycomb ceramic to improve its thermal shock resistance and reduce cracking after repeated heating and cooling. Silicon carbide powder is typically used as the main plugging material. However, the wear resistance or hardness of such plugging materials often does not match that of the honeycomb ceramic matrix.

[0004] A mismatch in wear resistance or hardness means that the plugging material and the honeycomb ceramic will perform differently under the same wear conditions. If the plugging material has poor wear resistance, it will wear away quickly, leading to the exposure and vulnerability of the honeycomb ceramic. Conversely, if the plugging material has excessive wear resistance, it will exert stress on the compartments during end-face grinding, easily causing the compartments to crack or the plugging material to fall off.

[0005] Furthermore, because the silicon carbide cell strips contain a significant amount of pore-forming material, their wear resistance and hardness decrease after sintering. Related technologies involve adding pore-forming agents to the plugging material to similarly reduce its wear resistance and hardness, thus matching the two materials' properties. However, the addition of pore-forming material to the plugging material can easily lead to smoke leakage in the honeycomb ceramic, hindering particle capture and increasing the defect rate.

[0006] Therefore, it is very important to find a new method to control the hardness and wear resistance of plugging materials. Summary of the Invention

[0007] The purpose of this invention is to provide a honeycomb ceramic carrier, its preparation method, and its application. By adding metallic silicon, alumina, and strontium carbonate to traditional silicon carbide plugging materials, the hardness and wear resistance of the plugging materials are controlled to ensure that the bending strength of the plugged part and the ceramic unit in the honeycomb ceramic carrier are matched. This avoids damage to the honeycomb ceramic carrier during the end face grinding process during the preparation of the honeycomb ceramic carrier, thereby improving the yield of the honeycomb ceramic carrier during the preparation process. At the same time, it ensures that the honeycomb ceramic carrier has high mechanical strength and thermal shock resistance, and the preparation method is simple and low in cost.

[0008] To achieve the above objectives, the present invention provides the following technical solution: A honeycomb ceramic carrier, comprising: Multiple silicon carbide ceramic units, each having multiple compartments separated by partitions and extending longitudinally along the ceramic unit, the compartments forming a fluid flow path extending from the inlet end face to the outlet end face; Multiple plugging sections are provided at the ends of the air inlet and air outlet faces of the ceramic unit. The plugging sections are made by sintering raw materials containing silicon carbide, alumina, strontium carbonate, metallic silicon and additives. The ratio of the bending strength of the ceramic unit A-axis to the bending strength of the plugging part is 1:(0.8~1.9), the bending strength of the ceramic unit A-axis is 2.5MPa~38.5MPa, and the bending strength of the plugging part is 3MPa~35MPa.

[0009] To achieve the above objectives, the present invention also provides the following technical solution: A method for preparing the above-mentioned honeycomb ceramic carrier includes the following steps: S10 provides raw materials containing silicon carbide, alumina, strontium carbonate, metallic silicon and additives, and mixes them to obtain a honeycomb ceramic plugging material; S30, providing the ceramic unit body; and S50, the honeycomb ceramic plugging material is used to plug the holes in the ceramic unit, and the honeycomb ceramic carrier is obtained by sintering, splicing and end face grinding.

[0010] To achieve the above objectives, the present invention also provides the following technical solution: Application of the above-mentioned honeycomb ceramic support or the honeycomb ceramic support obtained by the above preparation method as a catalyst support in waste gas treatment.

[0011] Other applicable fields will become apparent from the description provided in this invention.

[0012] To achieve the above objectives, the present invention further provides the following technical solution: A method for predicting the flexural strength of the plugged portion in a honeycomb ceramic carrier as described above, or the plugged portion in a honeycomb ceramic carrier obtained by the above preparation method, includes the following steps: S20, obtaining the weight proportions of silicon carbide, strontium carbonate, and alumina in the plugging material of the honeycomb ceramic carrier; and S40, according to the formula Z=1.7622×e (0.0563·Si+0.7616·Sr+0.9898·Al) Calculate the bending strength of the plugged portion, where Z is the bending strength of the plugged portion, Si is the weight parts of silicon carbide, Sr is the weight parts of strontium carbonate, and Al is the weight parts of alumina.

[0013] In this invention, the bending strength of the plugging material mainly depends on the mass ratio of silicon carbide, strontium carbonate, and alumina. Its bending strength can be predicted by formula Z to match a suitable ceramic unit.

[0014] The descriptions and specific examples in the invention summary are intended to be illustrative only and are not intended to limit the scope of the invention.

[0015] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects: The honeycomb ceramic carrier provided by this invention adjusts the hardness and wear resistance of the plugged part by adding metallic silicon, alumina and strontium carbonate to traditional silicon carbide plugging material, ensuring that its bending strength and the bending strength of the ceramic unit have a higher degree of matching, thereby avoiding the damage of the honeycomb ceramic carrier during the end face grinding process during the preparation of the honeycomb ceramic carrier, thereby improving the yield of the honeycomb ceramic carrier in the preparation process, while ensuring that the honeycomb ceramic carrier has high mechanical strength, and the preparation method is simple and low cost. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other solutions can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of a honeycomb ceramic carrier provided in one embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a ceramic unit body provided in one embodiment of the present invention; Figure 3 A flowchart illustrating a method for preparing a cellular ceramic carrier according to an embodiment of the present invention; Figure 4 This is a flowchart illustrating a method for predicting the bending strength of the plugged portion in a honeycomb ceramic carrier according to an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It should be understood that the specific embodiments described herein are only for illustration and explanation of the present invention and are not intended to limit the present invention.

[0019] Any specific numerical values ​​disclosed herein (including the endpoints of numerical ranges) are not limited to their exact values, but should be understood to also include values ​​close to the exact value, such as all possible values ​​within ±5% of the exact value. Furthermore, with respect to the disclosed numerical ranges, one or more new numerical ranges can be obtained by arbitrarily combining the endpoint values ​​of the range, the endpoint values ​​with specific point values ​​within the range, and the specific point values ​​themselves; these new numerical ranges should also be considered as specifically disclosed herein.

[0020] The terminology used in this invention is for the purpose of describing specific exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” as used herein are intended to include the plural forms as well. The terms “comprising,” “including,” “containing,” and “having” are inclusive and thus describe the presence of said features, elements, compositions, steps, integers, operations, and / or components, but do not exclude the presence or inclusion of one or more other features, integers, steps, operations, elements, components, and / or sets thereof. Although the open-ended term “comprising” should be understood as a non-limiting term used to describe and claim the various embodiments described in this invention, in some aspects it may instead be understood as a more restrictive and limiting term, such as “consisting of” or “essentially composed of.” Thus, for any given embodiment describing a composition, material, component, element, feature, integer, operation, and / or process step, the invention also particularly includes embodiments consisting of or substantially consisting of such compositions, materials, components, elements, features, integers, operations, and / or process steps. In the case of “consisting of…”, the alternative embodiments exclude any additional compositions, materials, components, elements, features, integers, operations and / or process steps. In the case of “essentially composed of…”, any additional compositions, materials, components, elements, features, integers, operations and / or process steps that substantially affect the essential and novel characteristics are excluded from such embodiments. However, any compositions, materials, components, elements, features, integers, operations and / or process steps that do not substantially affect the essential and novel characteristics may be included in the embodiments.

[0021] Any method steps, processes, and operations described in this invention should not be construed as necessarily requiring them to be performed in the specific order discussed or shown, unless explicitly specified. It should also be understood that, unless otherwise stated, additional or alternative steps may be used.

[0022] In this invention, except where expressly stated, any matters or issues not mentioned are directly applicable to those known in the art without any modification. Furthermore, any embodiment described in this invention can be freely combined with one or more other embodiments described in this invention, and the resulting technical solutions or concepts are considered part of the original disclosure or original record of this invention, and should not be regarded as new content not disclosed or anticipated by this invention, unless those skilled in the art consider the combination to be clearly unreasonable.

[0023] Unless otherwise stated, the terms used herein have the same meaning as commonly understood by those skilled in the art, and if a term is defined herein and its definition differs from the common understanding in the art, the definition herein shall prevail.

[0024] Unless otherwise stated, when % is mentioned in this document, it refers to wt%.

[0025] It is worth noting that "cpsi" in this application specification refers to channels per square inch, which means "the number of channels per square inch of cross-section", commonly known as "mesh count".

[0026] It is understood that the "shrinkage rate" in this application refers to the percentage reduction in the size of the honeycomb ceramic material before and after sintering during the sintering process. The shrinkage rate described in this application was measured under the following conditions: the length, width, and height of the unit cell before and after sintering were measured using vernier calipers, and then calculated.

[0027] It is understood that “adhesive A” and “adhesive B”, “lubricant A” and “lubricant B” as described in this application specification are each independently selected from one or more components.

[0028] First aspect See Figures 1-2 This invention provides a honeycomb ceramic carrier comprising a plurality of silicon carbide ceramic unit cells 100. Each ceramic unit cell 100 has a plurality of compartments 11 separated by partitions and extending longitudinally along the ceramic unit cell, such as... Figure 2 The compartment 11 forms a fluid flow path extending from the air inlet end face 1A to the air outlet end face 1B.

[0029] The honeycomb ceramic carrier also includes multiple plugging portions 12, which are disposed at the ends of the air inlet and air outlet faces of the ceramic unit 100, such as... Figure 2 As shown. The plugging part 12 is made by sintering raw materials containing silicon carbide, aluminum oxide, strontium carbonate, metallic silicon and additives.

[0030] In the aforementioned cellular ceramic carrier, the ratio of the bending strength of the ceramic unit A axis to the bending strength of the plugging portion is 1:(0.8~1.9).

[0031] The honeycomb ceramic carrier provided by this invention adjusts the hardness and wear resistance of the plugged part by adding metallic silicon, alumina and strontium carbonate to traditional silicon carbide plugging material, ensuring a higher degree of matching between its bending strength and the bending strength of the ceramic unit, thereby avoiding damage to the honeycomb ceramic carrier during the end face grinding process during the preparation of the honeycomb ceramic carrier, thus improving the yield of the honeycomb ceramic carrier in the preparation process, while ensuring that the honeycomb ceramic carrier has high mechanical strength and thermal shock resistance, and the preparation method is simple and low cost.

[0032] It should be noted that each ceramic unit 100 is distributed and connected within the cross-section of the honeycomb ceramic carrier, and the longitudinal direction of the ceramic unit 100 is the same as the longitudinal direction of the honeycomb ceramic carrier, such as... Figure 1 As shown.

[0033] In some embodiments of the present invention, the honeycomb ceramic carrier is a cylinder or a polygonal prism.

[0034] In the context of this invention, the bending strength of the ceramic unit along the A-axis has a meaning known in the art, representing the maximum stress per unit area resisting fracture when the material is subjected to a bending load in the A-axis direction (i.e., the axial direction of the honeycomb channels). This strength can be obtained by testing with instruments and methods known in the art. For example, a three-point bending test is typically used, and the strength is calculated by measuring the fracture load (formula: σ=3PL / 2bh², where P is the fracture load in N; L is the span in mm; b is the specimen width in mm; and h is the specimen thickness in mm).

[0035] The value of “1: (0.8~1.9)” mentioned above includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 1:0.8, 1:0.9, 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9; or any range of values ​​between them.

[0036] In some preferred embodiments, the ratio of the bending strength of the ceramic unit A axis in the cellular ceramic carrier to the bending strength of the plugging portion is 1:(0.8~1.2).

[0037] In some embodiments of the present invention, the bending strength of the ceramic unit A axis is 2.5MPa to 38.5MPa. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 3MPa, 5MPa, 10MPa, 15MPa, 20MPa, 25MPa, 30MPa, 35MPa, 38MPa; or any range of values ​​between them.

[0038] In some embodiments of the present invention, the bending strength of the plugging portion is 3MPa to 35MPa. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 3MPa, 5MPa, 8MPa, 10MPa, 12MPa, 15MPa, 18MPa, 20MPa, 22MPa, 25MPa, 28MPa, 30MPa, 32MPa; or any range of values ​​between them.

[0039] In some embodiments of the present invention, the mass ratio of alumina, strontium carbonate and metallic silicon in the plugging material is 1:(0.69~6.5):(10~52).

[0040] The values ​​of "1: (0.69~6.5): (10~52)" mentioned above include the minimum and maximum ratios within this range, as well as every ratio between the minimum and maximum ratios. Specific examples include, but are not limited to, the ratios in the embodiments and the following ratios: 1:1:10, 1:1.5:10, 1:2:10, 1:2.5:10, 1:3:10, 1:3.5:10, 1:4:10, 1:4.5:10, 1:5:10, 1:5.5:10, 1:6:10, 1:1:20, 1: 2:20, 1:3:20, 1:4:20, 1:5:20, 1:6:20, 1:6.5:20, 1:1:30, 1:2:30, 1:3:30, 1:4:30, 1:5:30, 1:6:30, 1:1:40, 1:2:40, 1:3:40, 1:4:40, 1:5:40, 1:6:40, 1:1:52, 1:2:52, 1:3:52, 1:4:52, 1:5:52, 1:6:52; or any range of values ​​between them.

[0041] In some embodiments of the present invention, the plugging part is made by sintering a raw material comprising the following components in parts by weight: 60 to 80 parts silicon carbide, 3 to 18.6 parts metallic silicon, 0.1 to 1.25 parts alumina, 0.38 to 1.68 parts strontium carbonate, and 7 to 10 parts additives.

[0042] In the context of this invention, metallic silicon refers to silicon with a content of about 98% and a small amount of impurities (such as iron, aluminum, and calcium). The crystal structure of metallic silicon is more stable than that of ordinary silicon, and it is a metallic crystal structure formed by a large number of silicon atoms connected by metallic bonds.

[0043] Among the above raw materials, silicon carbide is the main component, while metallic silicon, alumina and strontium carbonate are key components for adjusting the hardness and wear resistance of the material. Additives are components for adjusting the flowability of the material. Together they form a plugging material suitable for sealing silicon carbide honeycomb ceramics.

[0044] The above-mentioned "60 to 80 portions" values ​​include the minimum and maximum values ​​of this range, as well as every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 60 portions, 65 portions, 70 portions, 75 portions, 80 portions; or any range consisting of any two values.

[0045] The above-mentioned "3 to 14.5 parts" values ​​include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 3 parts, 5 parts, 8 parts, 10 parts, 12 parts, 14 parts, 14.5 parts; or any range consisting of any two values.

[0046] The above-mentioned "0.1 parts to 1.25 parts" values ​​include the minimum and maximum values ​​of this range, as well as every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 0.1 parts, 0.2 parts, 0.4 parts, 0.6 parts, 0.8 parts, 1.0 parts, 1.2 parts, 1.25 parts; or any range consisting of any two values.

[0047] The above-mentioned "0.16 parts to 1.68 parts" values ​​include the minimum and maximum values ​​of this range, as well as every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 0.16 parts, 0.18 parts, 1.0 parts, 1.2 parts, 1.4 parts, 1.6 parts, 1.68 parts; or any range consisting of any two values.

[0048] The above-mentioned "7 to 10 parts" values ​​include the minimum and maximum values ​​of this range, as well as every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, 10 parts; or any range consisting of any two values.

[0049] In some embodiments of the present invention, the silicon carbide in the plugging part is made of two different particle sizes. Specifically, the silicon carbide includes silicon carbide with a first particle size and silicon carbide with a second particle size. The D50 of the first particle size silicon carbide is 30μm to 50μm, and the D50 of the second particle size silicon carbide is 15μm to 30μm.

[0050] In the context of this invention, "D50" refers to the volume average particle size of silicon carbide particles, which has a meaning known in the art. It represents the particle size corresponding to a cumulative volume distribution percentage of 50% for the material, and can be tested using instruments and methods known in the art. For example, it can be conveniently tested using a laser particle size analyzer, such as the Mastersizer 2000E laser particle size analyzer from Malvern Instruments Ltd., UK, in accordance with GB / T 19077-2016 Particle Size Distribution Laser Diffraction Method.

[0051] The above-mentioned "30μm~50μm" values ​​include the minimum and maximum values ​​of this range, as well as every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 30μm, 32μm, 34μm, 36μm, 38μm, 40μm, 42μm, 44μm, 46μm, 48μm, 50μm; or any range consisting of any two values.

[0052] The above-mentioned "15μm~30μm" values ​​include the minimum and maximum values ​​of this range, as well as every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 15μm, 17μm, 19μm, 21μm, 23μm, 24μm, 25μm, 26μm, 27μm, 28μm, 30μm; or any range consisting of any two values.

[0053] Using two different particle sizes of silicon carbide can enhance the material's density and effectively prevent gas escape. Furthermore, the material's coefficient of thermal expansion can be adjusted.

[0054] In some embodiments of the present invention, the additive comprises binder A and lubricant A. The binder A and 3 to 5.5 parts of lubricant A are used. In some alternative embodiments, the adhesive A is 2 to 5 parts by weight, and specific examples of adhesive A may include one or more of polyvinyl alcohol, glycerol, ethyl cellulose, polyethylene glycol, methyl cellulose, potassium laurate, and carboxymethyl cellulose.

[0055] In some alternative embodiments, the lubricant A is obtained in parts by weight of 3 to 5.5 parts, and specific examples of the lubricant A may include one or more of glycerin, polyacrylamide liquid, paraffin oil and vegetable oil.

[0056] The above adhesives and lubricants will not have a negative effect on the mechanical properties of the material, such as its flexural strength.

[0057] In some embodiments of the present invention, the ceramic unit body is sintered from raw materials comprising the following weight fractions: 75-85 parts silicon carbide, 15-25 parts metallic silicon, 0.2-3 parts alkaline earth metal oxide, 15-25 parts binder B, 25-35 parts pore-forming agent, 0.5-1 part clay, and 3.5-5 parts lubricant B. In some alternative embodiments, the alkaline earth metal oxidation includes one or more of beryllium oxide, magnesium oxide, calcium oxide, strontium oxide, and barium oxide.

[0058] In some alternative embodiments, the adhesive B comprises one or more of polyvinyl alcohol, glycerol, ethyl cellulose, polyethylene glycol, methyl cellulose, potassium laurate, and carboxymethyl cellulose.

[0059] In some alternative embodiments, the lubricant B includes one or more of glycerin, polyacrylamide gel, paraffin oil, and vegetable oil.

[0060] In some alternative embodiments, the pore-forming agent includes one or more of the following: walnut powder, graphite, benzoic acid, starch, ammonium bicarbonate, ammonium chloride, polymethyl methacrylate, and expanded microspheres.

[0061] In some alternative embodiments, the clay includes one or more of kaolin, bentonite, montmorillonite, diatomite, perlite, illite, and petrolatum.

[0062] In an advantageous embodiment, the silicon carbide in the ceramic unit also uses two different particle sizes. In a more advantageous embodiment, the particle size of the silicon carbide used in the ceramic unit is the same as that of the silicon carbide used in the plugging section. Furthermore, the ceramic unit also uses a mixture of the first and second particle size silicon carbide as raw material, thereby advantageously achieving that the ceramic unit and the plugging section in the final obtained honeycomb ceramic carrier have the same or similar coefficients of thermal expansion.

[0063] In some embodiments of the present invention, the plugging portion comprises the following components by weight percentage: 70%~94% silicon carbide, 2%~7% silicon dioxide, 3%~8% silicon, 0.1%~2% strontium oxide, and 0.1%~2% aluminum oxide.

[0064] In some embodiments of the present invention, the ceramic unit comprises the following components by weight percentage: 60%~75% silicon carbide, 5%~15% silicon dioxide, 15%~30% silicon, 0.1%~2.5% alkaline earth metal oxides, and 0.1%~2.5% alumina.

[0065] In some embodiments of the present invention, the porosity of the honeycomb ceramic carrier is 40% to 70%. Understandably, the porosity of the honeycomb ceramic carrier can be 40%, 45%, 50%, 55%, 60%, 65%, 70%, and any value between them, or a range between any two values.

[0066] In some embodiments of the present invention, the shrinkage rate of the honeycomb ceramic carrier is less than 5%. Understandably, the shrinkage rate of the honeycomb ceramic carrier may be less than 5%, less than 4.5%, less than 4%, less than 3.5%, less than 3%, less than 2.5%, less than 2%, less than 1.5%, or less than 1%.

[0067] In some embodiments of the present invention, the pore density of the cellular ceramic carrier is 150 cpsi to 500 cpsi. Understandably, the pore density of the cellular ceramic carrier can be 150 cpsi, 200 cpsi, 250 cpsi, 300 cpsi, 350 cpsi, 400 cpsi, 450 cpsi, 500 cpsi, or any value between them, or a range between any two values.

[0068] Second aspect See Figure 3 The present invention provides a method for preparing the above-mentioned honeycomb ceramic carrier, comprising the following steps: S10 provides raw materials containing silicon carbide, alumina, strontium carbonate, metallic silicon and additives, and mixes them to obtain a honeycomb ceramic plugging material; S30, providing the ceramic unit body described in any of the above embodiments; and S50, the honeycomb ceramic plugging material is used to plug the holes in the ceramic unit, and the honeycomb ceramic carrier is obtained by sintering, splicing and end face grinding.

[0069] The sintering in step S50 may include oxygen-free sintering and oxidation sintering. Further, the sintering is performed sequentially as oxygen-free sintering and oxidation sintering. Both oxygen-free sintering and oxidation sintering are methods well-known to those skilled in the art.

[0070] In some embodiments of the present invention, the sintering temperature of the oxygen-free sintering is 1400℃~1500℃.

[0071] In some embodiments of the present invention, the sintering temperature of the oxidation sintering is 1200℃~1300℃.

[0072] Third aspect This invention provides an application of the above-mentioned honeycomb ceramic support or the honeycomb ceramic support obtained by the above preparation method as a catalyst support in waste gas treatment.

[0073] Specifically, in the field of waste gas treatment, the honeycomb ceramic carrier described in this invention or the honeycomb ceramic carrier obtained by the above preparation method can be used as a catalyst carrier in various devices such as internal combustion engines, boilers, chemical reaction equipment, and fuel cell reformers.

[0074] Fourth aspect See Figure 4 The present invention provides a method for predicting the flexural strength of the plugged portion in the above-described honeycomb ceramic carrier or the plugged portion in the honeycomb ceramic carrier obtained by the above-described preparation method, comprising the following steps: S20, obtaining the weight proportions of silicon carbide, strontium carbonate, and alumina in the plugging material of the honeycomb ceramic carrier; and S40, according to the formula Z=1.7622×e (0.0563·Si+0.7616·Sr+0.9898·Al) Calculate the bending strength of the plugged portion, where Z is the bending strength of the plugged portion, Si is the weight parts of silicon carbide, Sr is the weight parts of strontium carbonate, and Al is the weight parts of alumina.

[0075] In this invention, the bending strength of the plugging material mainly depends on the mass ratio of silicon carbide, strontium carbonate, and alumina. Its bending strength can be predicted by formula Z to match a suitable ceramic unit.

[0076] Example To better understand the present invention, the following description is provided in conjunction with embodiments. However, the scope of protection of the present invention is not limited to the scope of the embodiments.

[0077] In the following examples, unless otherwise specified, all experimental instruments and raw materials involved are commercially available products or can be prepared by known methods. Experimental methods not specifying particular conditions in the examples were performed under conventional conditions, such as those described in literature, books, or methods recommended by the manufacturer.

[0078] Unless otherwise specified, the specific parameters used in each step of the material preparation process in each embodiment and comparative example are the same. For example, the process parameters involved in the oxygen-free sintering step, such as the sintering temperature, are the same in each embodiment and comparative example.

[0079] Example 1 1. Hole plugging material 1) Prepare the following quantities of ingredients by weight: 40 parts of silicon carbide powder with a D50 of 35μm, 20 parts of silicon carbide powder with a D50 of 25μm, 6.69 parts of metallic silicon powder, 0.47 parts of alumina, 0.78 parts of strontium carbonate, 5 parts of glycerol, and 5 parts of vegetable oil.

[0080] 2) Mix the raw materials from step 1) above to obtain the plugging material.

[0081] 2. Honeycomb ceramic carrier 1) Provide the following parts by weight of raw materials: 80 parts silicon carbide powder, 18 parts metallic silicon powder, 1.5 parts magnesium oxide, 0.8 parts kaolin, 10 parts hydroxymethyl cellulose, 5 parts polyvinyl alcohol, 3 parts glycerol, 2.5 parts potassium laurate, 10 parts starch, and 5 parts walnut powder.

[0082] 2) Add all the raw materials from step 1) above to a high-speed mixer and mix at high speed for 15 minutes.

[0083] 3) Add 23wt% water and 3.5 parts polyacrylamide solution, which is the total mass of the solid raw materials, and continue to mix at high speed for 5 minutes.

[0084] 4) Add the raw material mixture obtained in step 3) to a biaxial kneader and knead for 15 minutes.

[0085] 5) Add the raw material mixture obtained in step 4) to the extruder for extrusion.

[0086] 6) Microwave drying to obtain unit blanks.

[0087] 7) Place the plugging material obtained in step 1 into the storage area of ​​the automatic plugging equipment. The automatic plugging equipment performs staggered plugging on the unit blank obtained in step 6) (i.e., alternately plugging the two ends of adjacent honeycomb channels). After plugging, the unit blank is subjected to oxygen-free sintering and oxidation sintering to obtain the sintered unit.

[0088] 8) Assemble the fired unit bodies obtained in step 7) and build them into a blank body of appropriate size according to the carrier specifications.

[0089] 9) Add splicing material to the splicing seam of the blank obtained in step 8) to obtain the unit body as a whole. The splicing material is any splicing material known to those skilled in the art.

[0090] 10) Grind the outer periphery and end face of the unit obtained in step 9) to obtain a silicon carbide honeycomb ceramic blank of appropriate size and shape.

[0091] 11) The polished silicon carbide honeycomb ceramic blank is skinned and dried.

[0092] Example 2 1. Hole plugging material 1) Prepare the following quantities of ingredients by weight: 47 parts of silicon carbide powder with a D50 of 35μm, 21 parts of silicon carbide powder with a D50 of 25μm, 14.44 parts of metallic silicon powder, 0.66 parts of alumina, 1.68 parts of strontium carbonate, 2 parts of glycerol, 2 parts of polyvinyl alcohol, and 5 parts of polyacrylamide liquid.

[0093] 2) Mix the raw materials from step 1) above to obtain the plugging material.

[0094] 2. Honeycomb ceramic carrier 1) Provide the following parts by weight of raw materials: 80 parts silicon carbide powder, 23 parts metallic silicon powder, 1 part beryllium oxide, 0.5 parts strontium oxide, 1 part kaolin, 10 parts ethyl cellulose, 10 parts polyethylene glycol, 5 parts graphite, and 4 parts expanded microspheres.

[0095] 2) Add all the raw materials from step 1) above to a high-speed mixer and mix at high speed for 15 minutes.

[0096] 3) Add 23wt% water, 2 parts vegetable oil, and 2 parts glycerin, and continue mixing at high speed for 5 minutes.

[0097] The remaining steps 4) to 11) are the same as steps 4) to 11) in Example 1.

[0098] Example 3 1. Hole plugging material 1) Prepare the following quantities of ingredients by weight: 35 parts of silicon carbide powder with a D50 of 30μm, 25 parts of silicon carbide powder with a D50 of 20μm, 5.12 parts of metallic silicon powder, 0.1 parts of alumina, 0.65 parts of strontium carbonate, 2 parts of potassium laurate, 3 parts of polyvinyl alcohol, and 3 parts of paraffin oil.

[0099] 2) Mix the raw materials from step 1) above to obtain the plugging material.

[0100] 2. Honeycomb ceramic carrier 1) Provide the following parts by weight of raw materials: 80 parts silicon carbide powder, 15 parts metallic silicon powder, 1.5 parts calcium oxide, 1 part diatomaceous earth, 10 parts carboxymethyl cellulose, 10 parts polyethylene glycol, 10 parts benzoic acid, 15 parts starch, and 5 parts expanded microspheres.

[0101] 2) Add all the raw materials from step 1) above to a high-speed mixer and mix at high speed for 15 minutes.

[0102] 3) Add 23wt% water, 3 parts glycerin, and 2 parts vegetable oil (based on the total mass of the solid raw materials), and continue mixing at high speed for 5 minutes.

[0103] The remaining steps 4) to 11) are the same as steps 4) to 11) in Example 1.

[0104] Example 4 1. Hole plugging material 1) Prepare the following quantities of ingredients by weight: 35 parts of silicon carbide powder with a D50 of 32μm, 25 parts of silicon carbide powder with a D50 of 26μm, 9.66 parts of metallic silicon powder, 0.85 parts of alumina, 0.88 parts of strontium carbonate, 1 part of glycerol, 1 part of polyvinyl alcohol, 1 part of methylcellulose, and 4 parts of vegetable oil.

[0105] 2) Mix the raw materials from step 1) above to obtain the plugging material.

[0106] 2. Honeycomb ceramic carrier 1) Provide the following parts by weight of raw materials: 80 parts silicon carbide powder, 20 parts metallic silicon powder, 0.5 parts calcium oxide, 0.5 parts strontium oxide, 0.5 parts magnesium oxide, 1 part illite, 5 parts potassium laurate, 10 parts methylcellulose, and 15 parts starch.

[0107] 2) Add all the raw materials from step 1) above to a high-speed mixer and mix at high speed for 15 minutes.

[0108] 3) Add 23wt% water and 4 parts paraffin oil (based on the total mass of the solid raw materials) and continue mixing at high speed for 5 minutes.

[0109] The remaining steps 4) to 11) are the same as steps 4) to 11) in Example 1.

[0110] Example 5 1. Hole plugging material 1) Prepare the following quantities of ingredients by weight: 28 parts of silicon carbide powder with a D50 of 45μm, 40 parts of silicon carbide powder with a D50 of 18μm, 3.20 parts of metallic silicon powder, 0.16 parts of alumina, 0.16 parts of strontium carbonate, 4 parts of glycerol, 1 part of polyvinyl alcohol, and 5.5 parts of paraffin oil.

[0111] 2) Mix the raw materials from step 1) above to obtain the plugging material.

[0112] 2. Honeycomb ceramic carrier 1) Provide the following parts by weight of raw materials: 80 parts silicon carbide powder, 0 parts metallic silicon powder, 1.5 parts strontium oxide, 1 part petrolatum, 1 part perlite, 10 parts glycerol, 5 parts polyvinyl alcohol, 15 parts starch, 15 parts polymethyl methacrylate, 10 parts expanded microspheres, and 10 parts ammonium bicarbonate.

[0113] 2) Add all the raw materials from step 1) above to a high-speed mixer and mix at high speed for 15 minutes.

[0114] 3) Add 23wt% water, 1 part glycerin, and 2.5 parts vegetable oil (based on the total mass of the solid raw materials), and continue mixing at high speed for 5 minutes.

[0115] The remaining steps 4) to 11) are the same as steps 4) to 11) in Example 1.

[0116] Example 6 1. Hole plugging material 1) Prepare the following quantities of ingredients by weight: 15 parts of silicon carbide powder with a D50 of 50μm, 55 parts of silicon carbide powder with a D50 of 25μm, 12.42 parts of metallic silicon powder, 1.24 parts of alumina, 0.85 parts of strontium carbonate, 1 part of polyvinyl alcohol, 1 part of polyethylene glycol, 1 part of glycerin, and 2.5 parts of vegetable oil.

[0117] 2) Mix the raw materials from step 1) above to obtain the plugging material.

[0118] 2. Honeycomb ceramic carrier 1) Provide the following parts by weight of raw materials: 75 parts silicon carbide powder, 25 parts metallic silicon powder, 1 part magnesium oxide, 0.5 parts strontium oxide, 3 parts illite, 1 part bentonite, 10 parts glycerol, 6 parts methylcellulose, and 18 parts walnut powder.

[0119] 2) Add all the raw materials from step 1) above to a high-speed mixer and mix at high speed for 15 minutes.

[0120] 3) Add 23wt% water, 1 part glycerin, 1 part vegetable oil, and 4 parts paraffin oil of the total weight of the solid raw materials, and continue to mix at high speed for 5 minutes.

[0121] The remaining steps 4) to 11) are the same as steps 4) to 11) in Example 1.

[0122] Example 7 1. Hole plugging material 1) Prepare the following quantities of ingredients by weight: 40 parts of silicon carbide powder with a D50 of 35μm, 40 parts of silicon carbide powder with a D50 of 25μm, 6.69 parts of metallic silicon powder, 0.47 parts of alumina, 0.78 parts of strontium carbonate, 5 parts of glycerol, 2.5 parts of glycerol, and 2.5 parts of paraffin oil.

[0123] 2) Mix the raw materials from step 1) above to obtain the plugging material.

[0124] 2. Honeycomb ceramic carrier It is basically the same as Example 4, except that the plugging material in step 7) is the plugging material described above.

[0125] Comparative Example 1 1. Hole plugging material Same as Example 3.

[0126] 2. Honeycomb ceramic carrier It is basically the same as Example 2, except that the plugging material in step 7) is the same as the plugging material in Example 3.

[0127] Comparative Example 2 1. Hole plugging material Same as Example 1.

[0128] 2. Honeycomb ceramic carrier It is basically the same as Example 5, except that the plugging material in step 7) is the same as the plugging material in Example 1 (the same plugging material in Example 1).

[0129] Comparative Example 3 1. Hole plugging material 1) Prepare the following quantities of ingredients by weight: 40 parts of silicon carbide powder with a D50 of 39 μm, 40 parts of silicon carbide powder with a D50 of 15 μm, 0 parts of metallic silicon powder, 0 parts of alumina, 0 parts of strontium carbonate, 2 parts of ethyl cellulose, 1 part of carboxymethyl cellulose, and 5 parts of glycerol.

[0130] 2) Mix the raw materials from step 1) above to obtain the plugging material.

[0131] 2. Honeycomb ceramic carrier It is basically the same as Example 1, except that the plugging material in step 7) is the plugging material mentioned above.

[0132] Comparative Examples 4-9 It is basically the same as Example 1, except that the raw materials and amounts of the plugging material are different, as detailed in Table 1.

[0133] The raw materials and their amounts used in the preparation methods of the plugging materials in Examples 1-7 and Comparative Examples 1-9 are listed in Table 1 below. It should be noted that p in Table 1 is the mass ratio of alumina, strontium carbonate, and metallic silicon in the plugging material raw materials: Table 1

[0134] Test case The performance of the honeycomb ceramic carrier materials obtained in the above embodiments and comparative examples was tested in the following manner and recorded in Table 2 below: (1) Bending strength of the plugging material The prepared plugging material was extruded and sintered to obtain a sample block of 25mm×25mm×60mm. The sample was measured using a universal testing machine from Suzhou Topbo, and the test method was the national standard: GB / T 4740-1999.

[0135] (2) Bending strength of unit A axis The bending strength of the unit was measured by preparing a sample block with a length, width, and height of 25mm × 25mm × 60mm and using a universal testing machine from Suzhou Topbo. The test method was in accordance with the national standard GB / T 4740-1999.

[0136] (3) Carrier end face grinding pass rate Take 100 honeycomb ceramic products after firing and perform end face grinding. Count the number of damaged products. The end face grinding pass rate = [(100 - number of damaged products) / 100] × 100%.

[0137] (4) Thermal shock resistance of the carrier The test plan is the one in Appendix C of the national standard GB / T 25994-2010.

[0138] (5) The Z value in Table 2 is the theoretical value of the bending strength of the plugging part material, which is based on the formula Z=1.7622×e (0.0563 ·Si+0.7616·Sr+0.9898·Al) The calculations show that Si is the weight percentage of silicon carbide in the plugging material, Sr is the weight percentage of strontium carbonate in the plugging material, and Al is the weight percentage of alumina in the plugging material.

[0139] Table 2

[0140] According to Table 2, comparing Examples 1-7 with Comparative Examples 1-9, it can be seen that the flexural strength of the plugging part formed by the raw materials containing metallic silicon, alumina and strontium carbonate is more adjustable, the flexural strength between the plugging part and the ceramic unit of the honeycomb ceramic carrier is better matched, the flexural strength is within the range of the above examples, and the end face grinding qualification rate of the honeycomb ceramic carrier is higher.

[0141] According to Table 2, comparing Examples 1-6 with Example 7, it can be seen that the ratio of the bending strength of the ceramic unit A axis to the bending strength of the plugging part is preferably 1:(0.8~1.9), more preferably 1:(0.8~1.2). When the ratio of the bending strength of the ceramic unit A axis to the bending strength of the plugging part is in the range of 1:(0.8~1.2), the end face grinding qualification rate of the honeycomb ceramic carrier is higher, reaching 99%.

[0142] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims. Furthermore, specific examples have been used in the specification to illustrate the principles and implementation methods of the present invention. The above description of the embodiments is only for the purpose of helping to understand the method and core ideas of the present invention, and the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A honeycomb ceramic carrier, characterized in that, include: Multiple silicon carbide ceramic units, each having multiple compartments separated by partitions and extending longitudinally along the ceramic unit, the compartments forming a fluid flow path extending from the inlet end face to the outlet end face; Multiple plugging sections are provided at the ends of the air inlet and air outlet faces of the ceramic unit. The plugging sections are made by sintering raw materials containing silicon carbide, alumina, strontium carbonate, metallic silicon and additives. The ratio of the bending strength of the ceramic unit A-axis to the bending strength of the plugging part is 1:(0.8~1.9), the bending strength of the ceramic unit A-axis is 2.5MPa~38.5MPa, and the bending strength of the plugging part is 3MPa~35MPa.

2. The honeycomb ceramic carrier according to claim 1, characterized in that, The ratio of the bending strength of the ceramic unit A axis to the bending strength of the plugging part is 1:(0.8~1.2).

3. The honeycomb ceramic carrier according to claim 1 or 2, characterized in that, The mass ratio of the alumina, the strontium carbonate and the metallic silicon is 1:(0.69~6.5):(10~52).

4. The honeycomb ceramic carrier according to claim 1 or 2, characterized in that, The plugging part is made by sintering raw materials comprising the following components in parts by weight: 60-80 parts silicon carbide Metallic silicon: 0 to 14.5 parts Alumina 3 parts to 1.25 parts, Strontium carbonate 0.16 parts to 1.68 parts, Additives: 7 to 10 parts.

5. The honeycomb ceramic carrier according to claim 4, characterized in that, The silicon carbide includes silicon carbide with a first particle size and silicon carbide with a second particle size, wherein the D50 of the first particle size silicon carbide is 30μm to 50μm and the D50 of the second particle size silicon carbide is 15μm to 30μm.

6. The honeycomb ceramic carrier according to claim 4, characterized in that, The additive comprises 2 to 5 parts of binder A and 3 to 5.5 parts of lubricant A; Optionally, the adhesive A includes one or more of polyvinyl alcohol, glycerol, ethyl cellulose, polyethylene glycol, methyl cellulose, potassium laurate, and carboxymethyl cellulose; Optionally, the lubricant A includes one or more of glycerin, polyacrylamide gel, paraffin oil, and vegetable oil.

7. The honeycomb ceramic carrier according to claim 1 or 2, characterized in that, The ceramic unit is made by sintering raw materials containing the following components in parts by weight: 75-85 parts of silicon carbide 15-25 parts of metallic silicon, 0.2-3 parts of alkaline earth metal oxides, Adhesive B 15-25 parts, 25-35 parts of pore-forming agent, 0.5 to 1 part clay Lubricant B: 3.5 to 5 parts; Optionally, the alkaline earth metal oxide includes one or more of beryllium oxide, magnesium oxide, calcium oxide, strontium oxide, and barium oxide; Optionally, the adhesive B comprises one or more of polyvinyl alcohol, glycerol, ethyl cellulose, polyethylene glycol, methyl cellulose, potassium laurate, and carboxymethyl cellulose; Optionally, the lubricant B includes one or more of glycerin, polyacrylamide gel, paraffin oil, and vegetable oil; Optionally, the pore-forming agent includes one or more of the following: walnut powder, graphite, benzoic acid, starch, ammonium bicarbonate, ammonium chloride, polymethyl methacrylate, and expanded microspheres. Optionally, the clay includes one or more of kaolin, bentonite, montmorillonite, diatomite, perlite, illite, and petrolatum.

8. The honeycomb ceramic carrier according to claim 1 or 2, characterized in that, The plugging portion comprises the following components by weight percentage: Silicon carbide 70%~94%, 2%~7% silicon dioxide Silicon 3%~8%, Strontium oxide 0.1%~2%, Alumina 0.1%~2%; And / or, the ceramic unit comprises the following components by weight percentage: Silicon carbide 60%~75%, 5%~15% silica Silicon 15%~30%, Alkaline earth metal oxides: 0.1%~2.5%, Alumina 0.1%~2.5%.

9. The honeycomb ceramic carrier according to any one of claims 1 to 8, characterized in that, The cellular ceramic carrier satisfies at least one of the following conditions (1) to (3): (1) The porosity of the honeycomb ceramic carrier is 40% to 70%; (2) The shrinkage rate of the honeycomb ceramic carrier is less than 5%; (3) The pore density of the honeycomb ceramic carrier is 150 cpsi ~ 500 cpsi.

10. A method for preparing a honeycomb ceramic carrier as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S10 provides raw materials containing silicon carbide, alumina, strontium carbonate, metallic silicon and additives, and mixes them to obtain a honeycomb ceramic plugging material; S30, providing the ceramic unit body; and S50, the honeycomb ceramic plugging material is used to plug the holes in the ceramic unit, and the honeycomb ceramic carrier is obtained by sintering, splicing and end face grinding.

11. The application of a honeycomb ceramic carrier as described in any one of claims 1 to 9 or a honeycomb ceramic carrier obtained by the preparation method described in claim 10 as a catalyst carrier in waste gas treatment.

12. A method for predicting the flexural strength of the plugged portion in a honeycomb ceramic carrier as described in any one of claims 1 to 9, or in a honeycomb ceramic carrier obtained by the preparation method as described in claim 10, characterized in that, Includes the following steps: S20, obtaining the weight proportions of silicon carbide, strontium carbonate, and alumina in the plugging material of the honeycomb ceramic carrier; and S40, according to the formula Z=1.7622×e (0.0563·Si+0.7616·Sr+0.9898·Al) Calculate the bending strength of the plugged portion, where Z is the bending strength of the plugged portion, Si is the weight parts of silicon carbide, Sr is the weight parts of strontium carbonate, and Al is the weight parts of alumina.

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