Thin-wall cordierite honeycomb ceramic material with high porosity and narrow pore size distribution and preparation method thereof

Abstract

The invention relates to the technical field of honeycomb ceramics, in particular to a thin-wall cordierite honeycomb ceramic material with high porosity and narrow pore size distribution and a preparation method. The diameter-thickness ratio of the flaky narrow-particle-size-distribution high-iron-content talc in the inorganic solid component is greater than or equal to 20; the sphericity degrees of the spherical aluminum oxide and the spherical silicon dioxide are both greater than or equal to 98%, and the mass percentage of an amorphous phase in the spherical silicon dioxide is greater than or equal to 99.0%; the particle morphology of the shaped coarse silicon carbide is ellipsoidal, the particle size D50 is 25-35 microns, and the ratio of the particle size D90 to the particle size D10 is smaller than or equal to 3.0 microns. Shaped coarse silicon carbide is adopted to replace an expensive organic pore-forming agent, and high porosity can be realized only by adding a small amount, so that the raw material cost is remarkably reduced; and by controlling the particle size distribution of the raw materials, the micropore distribution is remarkably narrowed, and the strict requirements on high PN trapping efficiency and low back pressure are met.

Description

Technical Field

[0001] This invention relates to the field of honeycomb ceramic technology, and more specifically, to thin-walled cordierite honeycomb ceramic materials with high porosity and narrow pore size distribution, and their preparation methods. Background Technology

[0002] Currently, the industry has further tightened the limits on pollutant emissions, especially for particulate matter, with the PN particle size limit being tightened from ≥23nm to ≥10nm.

[0003] Therefore, to achieve PN emission and fuel consumption standards, it is necessary to improve the particulate matter capture efficiency and reduce the back pressure of the wall-flow honeycomb ceramic carrier for vehicle exhaust. Improving capture efficiency and reducing back pressure are contradictory, and conventional techniques such as reducing the median pore size of the wall-flow carrier (increasing capture efficiency but also increasing back pressure) or increasing the porosity of the wall-flow carrier (reducing back pressure but also decreasing capture efficiency) cannot solve this problem. It is necessary to develop wall-flow carriers with narrow pore size distribution and high porosity, thin-walled structures.

[0004] Conventional preparation methods use flaky talc, flaky kaolin, and irregularly shaped alumina as main raw materials, adding a large amount of narrow-particle-size organic pore-forming agents to increase porosity. This method brings many problems, specifically: Narrow-particle-size organic pore-forming agents, such as polymethyl methacrylate microspheres (PMMA), polystyrene microspheres (PS), and superabsorbent polymer (SAP) microspheres, are expensive, significantly increasing costs. To obtain high porosity (>50%), a large amount of organic pore-forming agent (>20%) needs to be added. During sintering, a large amount of organic additives decompose rapidly, generating a large amount of heat, causing a temperature difference between the inside and outside of the honeycomb ceramic carrier, resulting in thermal stress. Furthermore, the thinning of the wall thickness (from 9-12 mil to 6-8 mil) weakens the strength of the green body, causing cracking during firing. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution and a preparation method thereof.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: This invention provides a thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution. The inorganic solid components of the honeycomb ceramic material include flaky narrow-particle-size high-iron-content talc, spherical alumina, spherical silica, and shaped coarse silicon carbide. The aspect ratio of the flaky, narrow-particle-size talc with high iron content is greater than or equal to 20. The sphericity of both the spherical alumina and the spherical silica is greater than or equal to 98%, and the mass percentage of the amorphous phase in the spherical silica is greater than or equal to 99.0%. The shaped coarse silicon carbide particles have an ellipsoidal morphology and a particle size D. 50 The particle size is 25-35 μm, D. 90 With particle size D 10 The ratio is less than or equal to 3.0 μm.

[0007] Based on the above technical solution, the present invention can be further improved as follows.

[0008] Furthermore, in the shaped crude silicon carbide, the mass percentage of calcium oxide is less than or equal to 0.3%, and the total mass percentage of potassium oxide and sodium oxide is less than 0.5%.

[0009] Furthermore, the particle size D of the flaky, narrow-particle-size, high-iron-content talc... 50 The particle size is 25-40 μm, D. 97 The particle size D of the spherical alumina is less than or equal to 60 μm. 50 The particle size D of the spherical silica is 5.0-12.0 μm. 50 It is 20-28μm.

[0010] Furthermore, in the flaky, narrow-particle-size, high-iron-content talc, the mass percentage of iron oxide is greater than or equal to 0.5%, the mass percentage of silicon oxide is greater than or equal to 59.0%, the mass percentage of magnesium oxide is greater than or equal to 30.0%, and the mass percentage of calcium oxide is less than or equal to 0.5%; in the spherical alumina, the mass percentage of alumina is greater than or equal to 99.0%; and in the spherical silica, the mass percentage of silica is greater than or equal to 99.5%.

[0011] Furthermore, the mass percentages of each component in the inorganic solid component are as follows: 42.61%-46.20% for the flaky narrow-particle-size high-iron talc, 35.29%-36.37% for the spherical alumina, 5.28%-15.08% for the spherical silica, and 7.00%-13.00% for the shaped crude silicon carbide.

[0012] Furthermore, the raw materials of the honeycomb ceramic material also include a binder and a lubricant; the binder is a polyvinyl alcohol binder, and the viscosity of the polyvinyl alcohol binder is 10000-20000 mPa·s in a 2% aqueous solution at 20°C; the lubricant is one or more of ethylene glycol, 1,2-propanediol, and polyethylene glycol.

[0013] Furthermore, the mass percentage of the adhesive is 2.6%-7.5% of the total mass of the inorganic solid components, and the mass percentage of the lubricant is 2.9%-7.0% of the total mass of the inorganic solid components.

[0014] Furthermore, the cellular ceramic material has a pore density of 200-400 cpsi, a wall thickness of 6-8 mil, a porosity greater than 63%, a median pore size of 8.0-18.0 μm, and a particle size D. 90 With degree D 10 The micropore distribution ratio is 2.98-4.50; the coefficient of thermal expansion of the honeycomb ceramic material is less than 0.5×10⁻⁶ between 25℃ and 800℃. -6 / ℃.

[0015] The present invention also provides a method for preparing thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution as described above, wherein a clay material containing the inorganic solid components is obtained, the clay material is kneaded into clay segments, the clay segments are extruded and dried to obtain a green body, the green body is fired, and the honeycomb ceramic material is obtained after cooling; the extrusion pressure is 2-4 MPa.

[0016] Furthermore, the firing temperature is 1400-1450℃, and the holding time is 15-25 hours.

[0017] The beneficial effects of this invention are as follows: (1) The thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution of the present invention uses shaped coarse silicon carbide instead of expensive organic pore-forming agents, which significantly reduces the cost of raw materials; (2) The thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution of the present invention utilizes the characteristic that shaped coarse silicon carbide oxidizes and decomposes at 1100-1400℃ to generate a large amount of carbon dioxide gas, and forms a large number of well-connected open micropores during high-temperature sintering. Only 7-13% is needed to achieve high porosity. (3) The thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution of the present invention uses flaky narrow-particle-size high iron content talc, spherical alumina and spherical silica, combined with shaped coarse silicon carbide. By controlling the particle size distribution of raw materials, the micropore distribution is significantly narrowed, which meets the strict requirements of high PN capture efficiency and low back pressure. (4) The preparation method of the thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution of the present invention optimizes the particle size and ratio of raw materials, so that the extrusion pressure is stably controlled within the range of 2-4 MPa. This ensures that the green body has sufficient strength to meet the requirements of thin-walled extrusion molding, and also ensures that the clay has good plasticity and fluidity, thus realizing the controllable preparation of 6-8mil ultra-thin-walled honeycomb structure. Attached Figure Description

[0018] Figure 1 This is a SEM image of silicon carbide S1 used in the embodiments of the present invention. Detailed Implementation

[0019] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0020] The high-porosity, narrow-pore-distribution thin-walled cordierite honeycomb ceramic material of the present invention comprises, in its inorganic solid components, plate-like narrow-particle-distribution high-iron-content talc, spherical alumina, spherical silica, and shaped coarse silicon carbide; the aspect ratio of the plate-like narrow-particle-distribution high-iron-content talc is greater than or equal to 20; the sphericity of both the spherical alumina and spherical silica is greater than or equal to 98%, and the mass percentage of the amorphous phase in the spherical silica is greater than or equal to 99.0%; the particle morphology of the shaped coarse silicon carbide is ellipsoidal, with a particle size D. 50 The particle size is 25-35 μm, D. 90 With particle size D 10 The ratio is less than or equal to 3.0 μm.

[0021] The thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution of the present invention does not use organic pore-forming agents, but uses coarsely shaped silicon carbide for pore formation, which can effectively reduce costs while maintaining excellent performance.

[0022] The pore-forming principle of coarsely shaped silicon carbide is as follows: Talc with a narrow, plate-like particle size distribution and high iron content forms a liquid phase above 950℃. The maximum liquid phase volume during cordierite synthesis occurs in the temperature range of 1300-1400℃. Under an oxidizing atmosphere, the coarsely shaped silicon carbide begins to oxidize slightly at 1100-1200℃, forming silicon dioxide and releasing carbon dioxide. At 1300-1400℃, it is completely oxidized to silicon dioxide and carbon dioxide, releasing a large amount of carbon dioxide gas. Due to the high viscosity of the cordierite liquid phase, the gas is not easily discharged. The high-temperature sintering process uses negative pressure sintering, releasing a large amount of carbon dioxide gas and forming numerous interconnected open micropores. Therefore, a high porosity (51-63%) and narrow pore size distribution (D) are obtained. 90 / D 10 The microstructure is ≤3.5; the silica formed by the oxidation of silicon carbide can also provide the silica component needed for the synthesis of cordierite, reducing the amount of spherical silica added and lowering the cost.

[0023] To address the microstructure and particle size of excessively coarse silicon carbide, this invention selects ellipsoidal particles without sharp corners and controls their particle size and particle size distribution, thereby forming the required median pore size micropores and micropore distribution.

[0024] Limiting the content of alkali metals and alkaline earth metals in excessively coarse silicon carbide can prevent the thermal expansion coefficient of the honeycomb ceramic carrier from being affected by excessive content of these components.

[0025] This invention does not specifically limit the content of free silicon and residual carbon in coarsely shaped silicon carbide. A small amount of free silicon can be hydrated to form silica sol during the preparation of clay, thereby increasing the strength of the green body and facilitating firing. Residual carbon is converted into carbon dioxide during firing, which helps to increase porosity.

[0026] In addition, a diameter-to-thickness ratio of 20 or greater for flaky, narrow-particle-size talc with high iron content is beneficial for the directional arrangement of talc and reduces the coefficient of thermal expansion of the product.

[0027] When spherical alumina and spherical silica are melted at high temperatures, the high-density alumina and silica transform into low-density cordierite, expanding in volume to form a loose, highly porous material. The high sphericity of both effectively improves the flowability of the powder.

[0028] The confinement of the amorphous phase in spherical silica ensures that the honeycomb ceramic material has a good coefficient of thermal expansion. If the content of the amorphous phase is too low, the content of the cristobalite phase will be too high. However, the transformation of the cristobalite phase into the cordierite phase is incomplete, leaving residues. The cristobalite phase has a very high coefficient of thermal expansion, resulting in a high overall coefficient of thermal expansion for the honeycomb ceramic carrier, poor thermal shock resistance, and a tendency to crack during use.

[0029] Preferably, the shaped coarse silicon carbide of the present invention can be selected from refractory-grade silicon carbide raw materials, which are low in cost and easy to obtain, and can effectively reduce the production cost of honeycomb ceramic carrier materials.

[0030] Preferably, in the shaped crude silicon carbide, the mass percentage of calcium oxide is less than or equal to 0.3%, and the total mass percentage of potassium oxide and sodium oxide is less than 0.5%.

[0031] Preferably, the particle size D of the flaky, narrow-particle-size talc with high iron content is... 50 The particle size is 25-40 μm, D. 97 The particle size should be less than or equal to 60 μm. The above particle size limit can prevent coarse particles of high-iron-content talc with a narrow particle size distribution from clogging the mold and causing appearance defects such as missing grids and deformed channels in the product. When the conversion rate of alumina to cordierite is low, the unconverted part will be converted into corundum crystal phase with a large coefficient of thermal expansion. The particle size limit can prevent the above situation from occurring.

[0032] The coarse, flaky, narrow-particle-size talc with high iron content occupies the position to form a liquid phase at high temperatures (>1050℃). Under the action of capillary force, the liquid phase migrates to spherical alumina and spherical molten silica particles, reacting to form cordierite, leaving pores and forming micropores.

[0033] Preferably, the particle size D of spherical alumina 50The particle size is 5.0-12.0μm; the spherical alumina particles can be as coarse as possible while ensuring the formation of deposited pores.

[0034] Preferably, the particle size D of the spherical silica is... 50 It is 20-28μm.

[0035] Preferably, in the flaky, narrow-particle-size talc with high iron content, the mass percentage of iron oxide is greater than or equal to 0.5%, the mass percentage of silicon oxide is greater than or equal to 59.0%, the mass percentage of magnesium oxide is greater than or equal to 30.0%, and the mass percentage of calcium oxide is less than or equal to 0.5%; in the spherical alumina, the mass percentage of alumina is greater than or equal to 99.0%; and in the spherical silica, the mass percentage of silica is greater than or equal to 99.5%.

[0036] Talc with high iron content exhibits a low temperature and a large volume of liquid phase, which is conducive to the formation of high porosity. Shaped silicon carbide, under an oxidizing atmosphere, begins to undergo slight oxidation at 1100-1200℃, forming silica and releasing carbon dioxide. At 1300-1400℃, it is completely oxidized to silica and carbon dioxide, releasing a large amount of carbon dioxide gas. Due to the high viscosity of the cordierite liquid phase, the gas is not easily expelled. The high-temperature sintering process employs negative pressure sintering, releasing a large amount of carbon dioxide gas and forming numerous interconnected open micropores. Therefore, a high porosity (51-63%) and narrow pore size distribution (D) are obtained. 90 / D 10 Microstructure of ≤3.5).

[0037] Preferably, spherical alumina and spherical silica can be prepared by flame method.

[0038] In the inorganic solid component of this invention, the mass percentages of each component are as follows: 42.61%-46.20% of flaky narrow-particle-size talc with high iron content, 35.29%-36.37% of spherical alumina, 5.28%-15.08% of spherical silica, and 7.00%-13.00% of shaped coarse silicon carbide.

[0039] The raw materials of the honeycomb ceramic material of the present invention also include binders and lubricants.

[0040] The adhesive is polyvinyl alcohol (PVA) adhesive, with a viscosity of 10,000-20,000 mPa·s in a 2% aqueous solution at 20°C.

[0041] Using high-viscosity water-soluble polyvinyl alcohol (PVA) as a binder has the advantages of high viscosity, low dosage, and favorable firing conditions. Water-soluble PVA reacts easily with water, has good film-forming properties, and helps improve the plasticity and flowability of the clay. At the same time, the long molecular chain of PVA means it does not burn and decomposes rapidly during sintering, and has a wide carbonization temperature range, which is also beneficial for firing.

[0042] The lubricant is a water-soluble, low-molecular-weight polyol. Based on the principle of "like dissolves like," the polyol can promote the dissolution of polyvinyl alcohol (PVA), which is beneficial to the fluidity of the clay and reduces the elastic deformation of the clay caused by the use of PVA. At the same time, the low molecular weight polyol has a low volatilization temperature and is easy to decompose and volatilize at low temperatures, reducing heat accumulation and reducing firing cracking.

[0043] Preferably, the lubricant can be one or more of ethylene glycol, 1,2-propanediol, and polyethylene glycol.

[0044] Preferably, the mass percentage of the binder is 2.6%-7.5% of the total mass of the inorganic solid components, and the mass percentage of the lubricant is 2.9%-7.0% of the total mass of the inorganic solid components.

[0045] Preferably, the raw materials of the cellular ceramic carrier of the present invention also include water, and the amount of water added is 20%-28.5% of the inorganic solid components.

[0046] The honeycomb ceramic material of this invention has a pore density of 200-400 cpsi, a wall thickness of 6-8 mil, a porosity greater than 63%, a median pore size of 8.0-18.0 μm, and a particle size D. 90 With degree D 10 The micropore distribution ratio is 2.98-4.50; the coefficient of thermal expansion of the honeycomb ceramic material is less than 0.5×10⁻⁶ between 25℃ and 800℃. -6 / ℃.

[0047] Preferably, in the structure of the honeycomb ceramic carrier material of the present invention, the shape of the honeycomb grid is not particularly limited. It can adopt a single hole shape such as triangle, square, or hexagon, or it can adopt multiple hole shapes such as square, hexagon, or asymmetrical. It is not necessary to adopt a single hole shape in the honeycomb structure. It is preferred to adopt, for example, a square hole.

[0048] Preferably, the diameter of the cellular ceramic carrier material of the present invention is 4.0-13 inches and the height is 3-12 inches. These dimensions are conventional in actual use and can be determined by cutting during the preparation process.

[0049] The present invention discloses a method for preparing thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution. The method involves obtaining clay containing inorganic solid components, kneading the clay into clay segments, extruding and drying the clay segments to obtain a green body, firing the green body, and cooling it to obtain the honeycomb ceramic material. The extrusion pressure is 2-4 MPa.

[0050] Based on the inorganic solid components and other components of the honeycomb ceramic material of the present invention, the extrusion pressure required in its preparation method is low, which effectively reduces the energy consumption of preparation and optimizes the preparation process.

[0051] Preferably, the firing temperature is 1400-1450℃ and the holding time is 15-25 hours.

[0052] In one embodiment of the present invention, the preparation method specifically includes the following steps: S1. Use an inclined high-pressure mixer to mix the dry powder of inorganic solid components and binder for 0.5-1.0 hours to obtain a uniform mixed powder.

[0053] S2. Place the mixed powder in a kneading machine, add polyethylene glycol and purified water, and knead for 30-60 minutes to obtain mud.

[0054] S3. The clay is processed into plastic clay segments using a clay kneading machine. Vacuuming is required during the kneading process, and the vacuum level must be maintained above -0.095MPa.

[0055] S4. The mud segments are extruded into a honeycomb structure using a continuous extruder, and the green body is obtained by dielectric drying.

[0056] S5. Perform precise dimensional cutting on the green body.

[0057] S6. The green body is fired and then cold-worked to obtain a thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution.

[0058] The effects of the present invention will be illustrated below through specific embodiments and comparative examples.

[0059] Table 1 lists the specific parameters of the inorganic solid components in each embodiment. Among them, the flaky narrow-particle-size high-iron-content talc is specifically talc T1, talc T2, and talc T3; the spherical alumina is specifically alumina A1, alumina A2, and alumina A3; the spherical silica is specifically silica F1, silica F2, and silica F3; and the shaped coarse silicon carbide is specifically silicon carbide S1, silicon carbide S2, and silicon carbide S3.

[0060] SEM image of silicon carbide S1 as shown Figure 1 As shown.

[0061] Loss on ignition (LOI) of flaky, narrow-particle-size, high-iron-content talc refers to the percentage of weight lost by the raw material dried at 105-110℃ after ignition at 1000-1100℃. The components lost on ignition are mainly those decomposed by heat, such as water or carbon dioxide, and also include some organic matter. In this invention, the LII is primarily water of crystallization.

[0062] Table 2 lists the specific proportions of the inorganic solid components, binder, lubricant, and water in each embodiment. The mass percentages of the binder, lubricant, and water are based on the inorganic solid components being 100%.

[0063] Comparative Example 1 uses a conventional method for synthesizing cordierite, with the following specific components: 41.36% flaky talc, 42.94% flaky kaolin, 15.69% alumina, 45% pore-forming agent (starch), 7.5% high-viscosity (6000-10000mPa.s) HPMC, and 6% fatty acids.

[0064] Table 3 shows the performance test results of the examples and comparative examples.

[0065] Table 1. List of Raw Material Shapes Table 2. Component proportions of each embodiment Table 3 Comparison of the performance of honeycomb ceramics in each embodiment and comparative example The performance test results of Examples 1-10 show that the extrusion pressure tends to increase with increasing pore density and thinner wall thickness, but all examples are controlled within the range of 2-4 MPa. Under the same pore density and wall thickness conditions, the finer the raw material particle size, the lower the extrusion pressure. This is because fine-grained raw materials have a large specific surface area and relatively poor flowability, but the reduced interparticle friction is actually beneficial to reducing the extrusion pressure. At the same time, the refinement of the raw material reduces the median pore size and increases the reactivity, making it easier to synthesize cordierite phase, thereby reducing the coefficient of thermal expansion and improving thermal shock resistance.

[0066] On the other hand, as the particle size of flaky narrow-particle-size talc, spherical alumina, spherical silica, and coarse silicon carbide increases, the porosity significantly increases, reaching a maximum of 65.99%. Although the coefficient of thermal expansion increases somewhat, it is still controlled at 0.5 × 10⁻⁶. -6 Below / ℃, the thermal shock resistance meets the requirement of not cracking after three cycles at 800℃. Furthermore, the narrower the particle size distribution of the raw material, the narrower the micropore distribution, with the optimal value reaching D. 90 / D 10 ≤3.0, which is far superior to 6.12 in Comparative Example 1.

[0067] This invention uses crude silicon carbide as a pore-forming agent, which exhibits excellent pore-forming ability. Only 7-13% can achieve a porosity of 51-65.99%, and the median pore size can be controlled within the range of 8.0-18.0 μm. Its elliptical particles without sharp corners easily form accumulated pores. The CO2 gas released by high-temperature oxidation can form a large number of well-connected open micropores. The SiO2 generated by oxidation can also be used as a component source for synthesizing cordierite to reduce the amount of spherical silicon dioxide added and reduce costs.

[0068] Compared with Comparative Example 1, which uses starch or graphite as a pore-forming agent, the embodiments of the present invention show significant advantages in terms of porosity, micropore distribution, coefficient of thermal expansion and thermal shock resistance, which can meet the application requirements of different wall-flow carriers and are suitable for catalyst carriers such as GPF, DPF, and SCRF.

[0069] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution, characterized in that, The inorganic solid components of the honeycomb ceramic material include flaky, narrow-particle-size, high-iron-content talc, spherical alumina, spherical silica, and shaped coarse silicon carbide. The aspect ratio of the flaky, narrow-particle-size talc with high iron content is greater than or equal to 20. The sphericity of both the spherical alumina and the spherical silica is greater than or equal to 98%, and the mass percentage of the amorphous phase in the spherical silica is greater than or equal to 99.0%. The shaped coarse silicon carbide particles have an ellipsoidal morphology and a particle size D. 50 The particle size is 25-35 μm, D. 90 With particle size D 10 The ratio is less than or equal to 3.0 μm.

2. The thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution according to claim 1, characterized in that, In the shaped crude silicon carbide, the mass percentage of calcium oxide is less than or equal to 0.3%, and the total mass percentage of potassium oxide and sodium oxide is less than 0.5%.

3. The thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution according to claim 1, characterized in that, The particle size D of the flaky, narrow-particle-size, high-iron-content talc 50 The particle size is 25-40 μm, D. 97 The particle size D of the spherical alumina is less than or equal to 60 μm. 50 The particle size D of the spherical silica is 5.0-12.0 μm. 50 It is 20-28μm.

4. The thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution according to claim 3, characterized in that, In the flaky, narrow-particle-size, high-iron-content talc, the mass percentage of iron oxide is greater than or equal to 0.5%, the mass percentage of silicon oxide is greater than or equal to 59.0%, the mass percentage of magnesium oxide is greater than or equal to 30.0%, and the mass percentage of calcium oxide is less than or equal to 0.5%; in the spherical alumina, the mass percentage of alumina is greater than or equal to 99.0%; and in the spherical silica, the mass percentage of silica is greater than or equal to 99.5%.

5. A thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution according to any one of claims 1-4, characterized in that, The inorganic solid components have the following mass percentages: 42.61%-46.20% for the flaky narrow-particle-size high-iron talc, 35.29%-36.37% for the spherical alumina, 5.28%-15.08% for the spherical silica, and 7.00%-13.00% for the shaped coarse silicon carbide.

6. A thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution according to any one of claims 1-4, characterized in that, The raw materials of the honeycomb ceramic material also include a binder and a lubricant; the binder is a polyvinyl alcohol binder, and the viscosity of the polyvinyl alcohol binder is 10000-20000 mPa·s in a 2% aqueous solution at 20°C; the lubricant is one or more of ethylene glycol, 1,2-propanediol, and polyethylene glycol.

7. A thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution according to claim 6, characterized in that, The binder comprises 2.6%-7.5% of the total mass of the inorganic solid components, and the lubricant comprises 2.9%-7.0% of the total mass of the inorganic solid components.

8. A thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution according to any one of claims 1-4, characterized in that, The honeycomb ceramic material has a pore density of 200-400 cpsi, a wall thickness of 6-8 mil, a porosity greater than 63%, a median pore size of 8.0-18.0 μm, and a particle size D. 90 With degree D 10 The micropore distribution ratio is 2.98-4.50; the coefficient of thermal expansion of the honeycomb ceramic material is less than 0.5×10⁻⁶ between 25℃ and 800℃. -6 / ℃.

9. A method for preparing a thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution as described in any one of claims 1-8, characterized in that, Obtain clay containing the inorganic solid components, knead the clay into clay segments, extrude and dry the clay segments to obtain a green body, fire the green body, and cool it to obtain the honeycomb ceramic material; the extrusion pressure is 2-4 MPa.

10. The method for preparing a thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution according to claim 9, characterized in that, The firing temperature is 1400-1450℃, and the holding time is 15-25 hours.

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