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CN-122010592-A - Thin-wall cordierite honeycomb ceramic material with high porosity and narrow pore size distribution and preparation method thereof

CN122010592ACN 122010592 ACN122010592 ACN 122010592ACN-122010592-A

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 thereof. The diameter-thickness ratio of the flaky narrow-particle-size-distribution high-iron-content talcum in the inorganic solid component is more than or equal to 20, the sphericity of the spherical alumina and the sphericity of the spherical silica are more than or equal to 98%, the mass percentage of an amorphous phase in the spherical silica is more than or equal to 99.0%, the particle morphology of the shaped coarse silicon carbide is ellipsoidal, the particle size D 50 is 25-35 mu m, and the ratio of the particle size D 90 to the particle size D 10 is less than or equal to 3.0 mu m. The plastic coarse silicon carbide is adopted to replace expensive organic pore forming agent, high porosity can be realized by adding a small amount, the raw material cost is obviously reduced, and the micropore distribution is obviously narrowed by controlling the raw material granularity distribution, so that the strict requirements on PN high trapping efficiency and low back pressure are met.

Inventors

  • PAN JIQING
  • WU XIONGHUI
  • HUANG FEIHUI
  • JIANG TAO
  • CHENG GUOYUAN
  • Pan Jieyu
  • DU YAN

Assignees

  • 安徽奥福精细陶瓷有限公司
  • 山东奥福环保科技股份有限公司
  • 重庆奥福精细陶瓷有限公司

Dates

Publication Date
20260512
Application Date
20260415

Claims (10)

  1. 1. The thin-wall cordierite honeycomb ceramic material with high porosity and narrow pore size distribution is characterized in that the inorganic solid components of the honeycomb ceramic material comprise flaky talcum with narrow particle size distribution and high iron content, spherical alumina, spherical silica and reshaped coarse silicon carbide; the diameter-thickness ratio of the flaky narrow-particle-size-distribution high-iron-content talcum is more than or equal to 20; the sphericity of the spherical alumina and the sphericity of the spherical silica are both more than or equal to 98 percent, and the mass percentage of an amorphous phase in the spherical silica is more than or equal to 99.0 percent; the particle shape of the shaped coarse silicon carbide is ellipsoidal, the granularity D 50 is 25-35 mu m, and the ratio of the granularity D 90 to the granularity D 10 is less than or equal to 3.0 mu m.
  2. 2. The thin-walled cordierite honeycomb ceramic material of claim 1, wherein the shaped coarse silicon carbide has a mass percent of calcium oxide of less than or equal to 0.3% and a total mass percent of potassium oxide and sodium oxide of less than 0.5%.
  3. 3. The thin-walled cordierite honeycomb ceramic material of claim 1, wherein the flake-like, narrow-particle-size-distribution high-iron-content talc has a particle size D 50 -40 μm and a particle size D 97 of 60 μm or less, the spherical alumina has a particle size D 50 of 5.0-12.0 μm, and the spherical silica has a particle size D 50 of 20-28 μm.
  4. 4. The thin-walled cordierite honeycomb ceramic material of claim 3, wherein the flake-form narrow-particle-size-distribution high-iron-content talc has a mass percentage of iron oxide of at least 0.5%, a mass percentage of silicon oxide of at least 59.0%, a mass percentage of magnesium oxide of at least 30.0%, a mass percentage of calcium oxide of at least 0.5%, a mass percentage of aluminum oxide of at least 99.0%, and a mass percentage of silicon dioxide of at least 99.5%.
  5. 5. The thin-walled cordierite honeycomb ceramic material of any one of claims 1-4, characterized in that the inorganic solid component comprises, by mass, the flake narrow particle size distribution high iron content talc 42.61% -46.20%, the spherical alumina 35.29% -36.37%, the spherical silica 5.28% -15.08%, and the shaped coarse silicon carbide 7.00% -13.00%.
  6. 6. The thin-walled cordierite honeycomb ceramic material with high porosity and narrow pore size distribution according to any one of claims 1 to 4, further comprising a binder and a lubricant, wherein the binder is a polyvinyl alcohol binder, the viscosity of the polyvinyl alcohol binder is 10000-20000mpa.s under an environment of 2% aqueous solution and 20 ℃, and the lubricant is one or more of ethylene glycol, 1, 2-propylene glycol and polyethylene glycol.
  7. 7. The thin-walled cordierite honeycomb ceramic material of claim 6, wherein the binder comprises 2.6-7.5% by mass of the total mass of the inorganic solid components and the lubricant comprises 2.9-7.0% by mass of the total mass of the inorganic solid components.
  8. 8. The thin-walled cordierite honeycomb ceramic material of any one of claims 1-4 having a high-porosity narrow-pore-size distribution having a pore density of 200-400cpsi, a wall thickness of 6-8mil, a porosity of greater than 63%, a median pore diameter of 8.0-18.0 μm, a micropore distribution ratio of particle size D 90 to degree D 10 of 2.98-4.50, and a coefficient of thermal expansion of less than 0.5x10 -6 /°c between 25 ℃ and 800 ℃.
  9. 9. A method for producing a thin-walled cordierite honeycomb ceramic material having a high porosity and a narrow pore diameter distribution according to any one of claims 1 to 8, wherein a pug containing the inorganic solid component is obtained, the pug is kneaded into a pug, the pug is extruded and dried to obtain a green body, the green body is fired, and the honeycomb ceramic material is obtained after cooling, and the extrusion pressure is 2 to 4MPa.
  10. 10. The method for producing a thin-walled cordierite honeycomb ceramic material with a high porosity and a narrow pore diameter distribution according to claim 9, wherein the firing temperature is 1400 to 1450 ℃ and the holding time is 15 to 25 hours.

Description

Thin-wall cordierite honeycomb ceramic material with high porosity and narrow pore size distribution and preparation method thereof Technical Field 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 thereof. Background At present, the pollutant emission limit is further tightened in the industry, especially for soot particles, the PN particle size limit is tightened from more than or equal to 23nm to more than or equal to 10nm. Therefore, in order for PN emission to reach the standard and fuel consumption to reach the standard, the soot particulate matter trapping efficiency of the wall-flow honeycomb ceramic carrier of the tail gas of the motor vehicle needs to be improved and the backpressure thereof needs to be reduced. The improvement of the trapping efficiency and the reduction of the back pressure are contradictory, and conventional technical means such as by reducing the median pore diameter of the wall-flow carrier (the improvement of the trapping efficiency but the increase of the back pressure) or by increasing the porosity of the wall-flow carrier (the reduction of the back pressure but the reduction of the trapping efficiency) cannot be solved. There is a need to develop a narrow pore size distribution, high porosity, thin walled wall flow support. The conventional preparation method uses platy talcum, platy kaolin and irregularly-shaped alumina as main raw materials, and adds a large amount of organic pore formers with narrow particle size distribution to improve the porosity, and the method brings a plurality of problems, specifically: Organic pore formers with narrow particle size distribution such as polymethyl methacrylate (PMMA), polystyrene (PS) and water absorbent resin (SAP) are expensive, resulting in a large increase in cost, and in order to obtain high porosity (> 50%), a large amount of organic pore formers (> 20%) needs to be added, and during sintering, a large amount of organic additives are rapidly decomposed to form a large amount of heat, resulting in the formation of an internal-external temperature difference of the honeycomb ceramic carrier, resulting in thermal stress, and thinning of wall thickness (6-8 mil from 9-12 mil), weakening of green body strength, resulting in firing cracking. Disclosure of Invention The invention aims to provide a thin-wall cordierite honeycomb ceramic material with high porosity and narrow pore size distribution and a preparation method thereof. The technical scheme for solving the technical problems is as follows: The invention provides a thin-wall cordierite honeycomb ceramic material with high porosity and narrow pore size distribution, wherein the inorganic solid component of the honeycomb ceramic material comprises flaky talcum with narrow particle size distribution and high iron content, spherical alumina, spherical silica and reshaped coarse silicon carbide; the diameter-thickness ratio of the flaky narrow-particle-size-distribution high-iron-content talcum is more than or equal to 20; the sphericity of the spherical alumina and the sphericity of the spherical silica are both more than or equal to 98 percent, and the mass percentage of an amorphous phase in the spherical silica is more than or equal to 99.0 percent; the particle shape of the shaped coarse silicon carbide is ellipsoidal, the granularity D 50 is 25-35 mu m, and the ratio of the granularity D 90 to the granularity D 10 is less than or equal to 3.0 mu m. On the basis of the technical scheme, the invention can be improved as follows. Further, in the shaped coarse silicon carbide, the mass percent of calcium oxide is less than or equal to 0.3 percent, and the total mass percent of potassium oxide and sodium oxide is less than 0.5 percent. Further, the particle size D 50 of the flaky narrow particle size distribution high-iron content talc is 25-40 μm, the particle size D 97 is less than or equal to 60 μm, the particle size D 50 of the spherical alumina is 5.0-12.0 μm, and the particle size D 50 of the spherical silica is 20-28 μm. Further, in the flaky narrow particle size distribution 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%, the mass percentage of calcium oxide is less than or equal to 0.5%, in the spherical alumina, the mass percentage of aluminum oxide is greater than or equal to 99.0%, and in the spherical silica, the mass percentage of silicon dioxide is greater than or equal to 99.5%. Further, in the inorganic solid component, the mass percentage of each component is that talcum with flaky narrow particle size distribution and high iron content 42.61% -46.20%, spherical alumina 35.29% -36.37%, spherical silicon dioxide