Ceramic fiber paperboard and method of making the same

Abstract

The application discloses a ceramic fiber paperboard and a preparation method thereof. The preparation method of the ceramic fiber paperboard comprises the following steps: a) placing aluminum silicate fibers in a corrosion solution for soaking to obtain aluminum silicate fibers with corroded surfaces; b) mixing and stirring the aluminum silicate fibers with the corroded surfaces with a modifier to obtain aluminum silicate fibers loaded with the modifier; c) performing calcination treatment on the aluminum silicate fibers loaded with the modifier, and removing impurities after cooling to obtain modified aluminum silicate fibers; d) preparing the modified aluminum silicate fibers into a slurry, adding a bonding agent for stirring to obtain a mixed slurry, and preparing a paperboard precursor based on the mixed slurry; and e) performing bonding agent impregnation treatment on the paperboard precursor, removing excess bonding agent, and drying and shaping to obtain a finished ceramic fiber paperboard. The ceramic fiber paperboard prepared by the preparation method has excellent physical properties, and the applicability of the ceramic fiber paperboard can be improved.

Description

Technical Field

[0001] This application relates to the field of paperboard technology, and in particular to a ceramic fiber paperboard and its preparation method. Background Technology

[0002] With rapid economic development, people's demand for automobiles is increasing, leading to a continuous rise in car ownership. This increase inevitably brings three problems to society: environmental pollution, energy consumption, and urban traffic congestion. The three-way catalytic converter plays a crucial role in reducing vehicle emissions. The gasket is an important component of the catalytic converter, fixing and supporting the carrier to prevent damage, while also providing sealing and heat insulation. The performance index and the rationality of the gasket's related parameter design directly affect the catalytic converter's encapsulation and service life.

[0003] Ceramic fiber paperboard, as a high-performance liner material for three-way catalytic converters, has attracted much attention due to its excellent high-temperature resistance and low thermal conductivity. However, ceramic fiber paperboard prepared by existing processes still has some shortcomings in physical properties. First, its compressive strength is weak, making it difficult to withstand the continuous pressure generated by the three-way catalytic converter during long-term operation. This may lead to deformation and damage of the liner material, thereby affecting the performance of the three-way catalytic converter. Second, although ceramic fiber paperboard has good high-temperature resistance, its performance may still degrade under extreme high-temperature environments, limiting its application at higher temperatures. In addition, the elastic bending cycle of ceramic fiber paperboard is also low, making it difficult to meet the requirements of three-way catalytic converters used in complex vibration environments. Summary of the Invention

[0004] This application provides a ceramic fiber paperboard and its preparation method, aiming to solve the problem that the physical properties of ceramic fiber paperboard prepared by existing processes are still lacking, affecting its use.

[0005] To achieve the above objectives, this application proposes a method for preparing ceramic fiber paperboard, comprising the following preparation steps: a) Immerse aluminum silicate fibers in a corrosive solution to obtain aluminum silicate fibers with corroded surfaces; b) The surface-corroded aluminum silicate fibers are mixed and stirred with a modifier to obtain aluminum silicate fibers coated with the modifier. c) The aluminum silicate fiber coated with the modifier is calcined and impurities are removed after cooling to obtain the modified aluminum silicate fiber. d) The modified aluminosilicate fiber is prepared into a slurry, and an adhesive is added and stirred to obtain a mixed slurry. A paperboard precursor is prepared based on the mixed slurry. e) The paperboard precursor is impregnated with adhesive to remove excess adhesive, and then dried and shaped to obtain the finished ceramic fiber paperboard.

[0006] In some embodiments, in step a), the corrosive solution is an acidic solution with a concentration of 5% to 12%; or, the corrosive solution is an alkaline solution with a concentration of 10% to 16%. The aluminum silicate fiber is immersed in the corrosion solution for 4 to 8 hours.

[0007] In some embodiments, the acidic solution includes hydrochloric acid solution, nitric acid solution, sulfuric acid solution, carbonic acid solution, and phosphoric acid solution; the alkaline solution includes magnesium hydroxide solution, calcium hydroxide solution, nickel hydroxide solution, and manganese hydroxide solution.

[0008] In some embodiments, in step b), the mass of the modifier is 2% to 8% of the mass of the surface-corroded aluminosilicate fibers; The modifier is a mixture of alumina and inorganic materials, wherein the inorganic materials are one or more of high-alumina bauxite clinker, clay clinker, and zircon sand.

[0009] In some embodiments, in step c), the calcination temperature is 900–1100°C and the calcination time is 10–30 min.

[0010] In some embodiments, in step d), the concentration of the slurry prepared from the modified aluminosilicate fiber ranges from 0.02% to 0.05%.

[0011] In some embodiments, in steps d) and e), the adhesive is a mixture of an organic adhesive and an inorganic adhesive, wherein the mass percentage of the organic adhesive to the inorganic adhesive is 1:1.

[0012] In some embodiments, the organic adhesive is one or more of phenolic resin, styrene-acrylic resin, polyvinyl acetate emulsion, and synthetic latex; the inorganic adhesive is one or more of water glass, silica sol, polyaluminum chloride, aluminum chromium phosphate, aluminum sulfate, and aluminum phosphate.

[0013] In some embodiments, in step d), the mass of the adhesive is 5% to 15% of the mass of the slurry.

[0014] This application also provides a ceramic fiber paperboard, which is prepared by the ceramic fiber paperboard preparation method described above.

[0015] This application proposes a ceramic fiber paperboard and its preparation method. The preparation method includes the following steps: a) immersing aluminosilicate fibers in a corrosion solution to obtain aluminosilicate fibers with a corroded surface; b) mixing the corroded aluminosilicate fibers with a modifier to obtain aluminosilicate fibers coated with the modifier; c) calcining the aluminosilicate fibers coated with the modifier and removing impurities after cooling to obtain modified aluminosilicate fibers; d) preparing the modified aluminosilicate fibers into a slurry, adding an adhesive and stirring to obtain a mixed slurry, and preparing a paperboard precursor based on the mixed slurry; e) immersing the paperboard precursor in the adhesive, and obtaining the finished ceramic fiber paperboard after pressing and shaping. In the preparation method proposed in this application, steps a) to c) are actually modifications of the aluminosilicate fibers, thereby changing the crystalline state of the aluminosilicate fibers, increasing the mullite phase, and improving the fiber's compressive strength, flexibility, strain resilience, high-temperature resistance, and corrosion resistance, thus improving its performance from the fiber raw material itself. Steps d) and e) are molding processes for ceramic fiber paperboard, adding adhesives to both the interior and surface of the paperboard, which enhances the paper strength. Therefore, the ceramic fiber paperboard prepared by the method provided in this application possesses excellent physical properties, improving its applicability. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 This is a schematic flowchart of a method for preparing ceramic fiber paperboard according to an embodiment of this application. Detailed Implementation

[0017] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0018] See Figure 1 As shown, this application proposes a method for preparing ceramic fiber paperboard, which includes the following preparation steps: a) Immerse aluminum silicate fibers in a corrosive solution to obtain aluminum silicate fibers with corroded surfaces.

[0019] In this step, the aluminosilicate fibers are placed in a corrosive solution to alter their smooth surface, etching grooves or trenches to provide loading space for the modifier in subsequent steps. This allows the modifier to adhere better to the aluminosilicate fiber surface, improving loading capacity and stability.

[0020] To accommodate subsequent steps, the aluminosilicate fibers used in this application are prepared by a blown fiber method. Blown fiber-prepared aluminosilicate fibers typically have shorter fiber lengths and finer fiber diameters, which facilitates fiber cutting, dispersion, and uniform distribution of the adhesive. The aluminosilicate fibers can also undergo necessary pretreatment, such as cleaning and drying, before being immersed in the etching solution to remove surface impurities and moisture.

[0021] Depending on the requirements, a corrosion solution that can effectively corrode aluminosilicate fibers without completely destroying their structure should be selected. The degree of corrosion can be controlled by adjusting conditions such as soaking time and stirring speed. Generally, a longer soaking time will accelerate the corrosion process, leading to excessive damage to the fiber structure.

[0022] In some embodiments, the etching solution is an acidic solution with a concentration of 5% to 12%; or, the etching solution is an alkaline solution with a concentration of 10% to 16%; wherein the aluminosilicate fibers are immersed in the etching solution for 4 to 8 hours. Thus, the type and corresponding concentration of the etching solution are selected, and the immersion time of the aluminosilicate fibers in the etching solution is set. The immersion time of 4 to 8 hours is chosen based on a comprehensive consideration of the degree of corrosion and the integrity of the fiber structure, ensuring that sufficient grooves or trenches are formed without causing excessive corrosion of the fibers.

[0023] Furthermore, acidic solutions include hydrochloric acid, nitric acid, sulfuric acid, carbonic acid, and phosphoric acid solutions; alkaline solutions include magnesium hydroxide, calcium hydroxide, nickel hydroxide, and manganese hydroxide solutions. By selecting appropriate acidic or alkaline solutions and controlling parameters such as their concentration, soaking time, and temperature, grooves or trenches can be effectively formed on the surface of aluminosilicate fibers, providing loading space for modifiers in subsequent steps.

[0024] b) The corroded aluminum silicate fibers are mixed and stirred with a modifier to obtain aluminum silicate fibers coated with the modifier.

[0025] In this step, the added modifier can improve the high-temperature resistance, flexibility, strain elasticity, and corrosion resistance of aluminosilicate fibers, solving the problem of brittleness, reduced toughness, and reduced strain elasticity of aluminosilicate fibers after the formation of the mullite phase during high-temperature treatment. This modifier is a high-temperature composite modifier.

[0026] When added, the modifier's mass is 2% to 8% of the mass of the surface-corroded aluminosilicate fibers; this ratio ensures uniform distribution and appropriate loading of the modifier on the aluminosilicate fibers. The modifier is a mixture of alumina and inorganic materials, with alumina as the main component, providing fundamental structural reinforcement and performance improvement for the aluminosilicate fibers. The inorganic materials are one or more of high-alumina bauxite clinker, clay clinker, and zircon sand. These are all high-temperature resistant inorganic materials, containing silicate components and high-temperature resistant elements such as aluminum, bauxite, and zircon, and also act as treatment agents and catalysts for high-temperature reactions, improving the efficiency of the high-temperature modification reaction.

[0027] c) The aluminum silicate fiber coated with the modifier is calcined and impurities are removed after cooling to obtain the modified aluminum silicate fiber.

[0028] In this step, the aluminum silicate fibers loaded with modifiers can be calcined in a calcining furnace. The calcination process can change the internal crystal structure of the aluminum silicate fibers and increase the mullite phase of the fibers, thereby obtaining high-performance aluminum silicate fibers and achieving the modification of aluminum silicate fibers.

[0029] The cooling process involves gradually reducing the temperature of the calcining furnace, allowing the aluminosilicate fibers to cool slowly. This process not only helps prevent cracking or damage to the aluminosilicate fibers due to sudden temperature drops but also promotes the uniform distribution of the modifier within the fibers. After cooling, the aluminosilicate fibers are removed from the calcining furnace and impurities are removed. Since some gaseous or solid impurities, such as fiber slag balls, may be generated during calcination, these impurities need to be removed to ensure the purity and performance of the aluminosilicate fibers.

[0030] Based on the properties of the modifier and aluminum silicate, a suitable calcination temperature and time are set. In some embodiments, the calcination temperature is between 900 and 1100°C, and the calcination time is between 10 and 30 minutes. Selecting appropriate calcination temperature and time can ensure the modification effect and obtain modified aluminum silicate fibers with excellent performance.

[0031] d) The modified aluminum silicate fiber is prepared into a slurry, and an adhesive is added and stirred to obtain a mixed slurry. The paperboard precursor is prepared based on the mixed slurry.

[0032] This step begins with the preparation of the slurry.

[0033] In the preparation of the pulp, an appropriate amount of modified aluminosilicate fibers needs to be weighed, and an appropriate amount of water needs to be prepared according to the characteristics of the fibers and the required pulp concentration. Then, the aluminosilicate fibers are slowly added to the water while stirring to ensure that the fibers are evenly dispersed in the water. This step can use a stirrer or mixer to accelerate the dispersion process. The pulp concentration can be adjusted by adding water or fibers as needed. Generally, the pulp concentration affects the subsequent performance and structure of the paperboard. In this embodiment, the concentration range of the pulp prepared from the modified aluminosilicate fibers is 0.02% to 0.05%.

[0034] Then, the adhesive is added to the slurry and stirred.

[0035] Depending on the application requirements and the performance requirements of the paperboard, a suitable adhesive needs to be selected. In this embodiment, the added adhesive is a mixture of organic and inorganic adhesives, with a mass ratio of 1:1. The organic adhesive increases the wet strength and room temperature strength of the product, while the inorganic adhesive ensures the high-temperature strength of the product. For example, the organic adhesive is one or more of phenolic resin, styrene-acrylic resin, polyvinyl acetate emulsion, and synthetic latex; the inorganic adhesive is one or more of water glass, silica sol, polyaluminum chloride, aluminum chromium phosphate, aluminum sulfate, and aluminum phosphate. A suitable amount of adhesive is further weighed and slowly added to the aluminosilicate fiber slurry. In this embodiment, the adhesive mass is 5% to 15% of the slurry mass to ensure the strength and stability of the prepared ceramic fiber paperboard. A stirrer or mixer can be used to thoroughly mix the adhesive with the slurry, ensuring that the adhesive is evenly distributed between the fibers. The specific stirring time and speed should be adjusted according to the characteristics of the slurry and the type of adhesive.

[0036] Finally, the paperboard precursor is prepared.

[0037] In this embodiment, an inclined wire paper machine is used to prepare the paperboard precursor, which is beneficial for the uniform dispersion of fibers and the uniformity of the paper after forming, while also making the basis weight and thickness of the material precisely controllable. The steps typically include feeding the mixed pulp into the inclined wire paper machine, and through the operation of the inclined wire paper machine, the pulp is formed into a continuous wet ceramic fiber paperboard on the equipment. After dewatering, compaction and drying, the paperboard precursor is obtained.

[0038] e) The paperboard precursor is impregnated with adhesive to remove excess adhesive, and then dried and shaped to obtain the finished ceramic fiber paperboard.

[0039] The purpose of this adhesive impregnation process is to achieve a dual effect of internal adhesive application and external sizing in the paperboard precursor, thereby improving the bonding strength of the fiber components. This impregnation process can be carried out using the sizing section of an inclined wire paper machine. This impregnation process breaks away from the traditional method of spraying adhesives, resulting in a more uniform distribution of the adhesive between the ceramic fiber paperboard components and improving the overall strength of the finished product.

[0040] One way to remove excess adhesive is to press the impregnated paperboard precursor. This allows the adhesive to penetrate the ceramic fiber paperboard more evenly and squeezes out excess adhesive, enabling the adhesive to be reused.

[0041] Based on the above-mentioned method for preparing ceramic fiber paperboard, various ceramic fiber paperboards were prepared through multiple experiments. These paperboards can be further used as raw materials for the liner layer of three-way catalytic converters, providing excellent performance support for the converters, such as high-temperature stability, corrosion resistance, bending resistance, wear resistance, and mechanical strength. They also help reduce the emission of harmful gases, meeting environmental protection requirements. The physical properties of the ceramic fiber paperboard were tested, and the results are shown in Table 1. Table 1

[0042] It is evident that the ceramic fiber paperboard prepared by the method proposed in this application exhibits improved physical properties compared to ceramic fiber paperboard prepared by traditional processes.

[0043] Based on the above-described method for preparing ceramic fiber paperboard, specific embodiments are provided below, and the ceramic fiber paperboards prepared based on each embodiment are subjected to relevant physical property tests. It is understood that the specific embodiments presented below are only some examples based on the above technical solutions, with variations in material selection and parameter settings. In some other specific embodiments, materials can be freely combined and parameters set within the scope of the technical solutions claimed in this application to prepare the ceramic fiber paperboard of this application.

[0044] Example 1 a) Immerse aluminum silicate fibers in a 5% hydrochloric acid solution for 6 hours to obtain aluminum silicate fibers with corroded surfaces.

[0045] b) After cleaning and drying the corroded aluminum silicate fibers, mix them with the modifier and stir to obtain aluminum silicate fibers coated with the modifier; the amount of modifier added is 5% of the mass of the corroded aluminum silicate fibers; the modifier ratio is alumina: high alumina bauxite clinker: zircon sand = 9: 0.5: 0.5.

[0046] c) The aluminosilicate fibers coated with the modifier are placed in a calcining furnace and calcined at 1000℃ for 20 minutes. Then, the calcined aluminosilicate fibers are taken out, cooled, and then screened and purified to remove fiber slag balls and other impurities, thus obtaining the modified aluminosilicate fibers.

[0047] d) The modified aluminosilicate fibers were prepared into an inorganic fiber slurry with a concentration of 0.03%. The dispersed slurry was pumped to a mixing tank, where 5% phenolic resin and 5% water glass were added to obtain a mixed slurry. The mixed slurry was then fed to the paperboard forming section of a wire paper machine to prepare wet ceramic fiber paperboard, which was then subjected to press drying and dewatering treatment to obtain the paperboard precursor.

[0048] e) The paperboard precursor is conveyed to the sizing section of the inclined wire paper machine, where adhesive impregnation is performed using a sizing device. The type and amount of adhesive are the same as those added to the pulp. After a pressing process to remove excess adhesive, the paperboard enters the drying section for drying and shaping to produce the finished ceramic fiber paperboard.

[0049] The physical properties of the ceramic fiber paperboard prepared in this embodiment are shown in Table 2: Table 2

[0050] Example 2 a) Immerse aluminum silicate fibers in an 8% hydrochloric acid solution for 4 hours to obtain aluminum silicate fibers with corroded surfaces.

[0051] b) After cleaning and drying the corroded aluminum silicate fibers, mix them with the modifier and stir to obtain aluminum silicate fibers coated with the modifier; the amount of modifier added is 2% of the mass of the corroded aluminum silicate fibers; the modifier ratio is alumina: high alumina bauxite clinker: zircon sand = 9: 0.5: 0.5.

[0052] c) The aluminosilicate fibers coated with the modifier are placed in a calcining furnace and calcined at 900°C for 10 minutes. Then, the calcined aluminosilicate fibers are taken out, cooled, and then screened and purified to remove fiber slag balls and other impurities, thus obtaining the modified aluminosilicate fibers.

[0053] d) The modified aluminosilicate fibers were prepared into an inorganic fiber slurry with a concentration of 0.03%. The dispersed slurry was pumped to a mixing tank, where 2.5% phenolic resin and 2.55% water glass were added to obtain a mixed slurry. The mixed slurry was then fed to the paperboard forming section of a wire paper machine to prepare wet ceramic fiber paperboard, which was then subjected to press drying and dewatering treatment to obtain the paperboard precursor.

[0054] e) The paperboard precursor is conveyed to the sizing section of the inclined wire paper machine, where adhesive impregnation is performed using a sizing device. The type and amount of adhesive are the same as those added to the pulp. After a pressing process to remove excess adhesive, the paperboard enters the drying section for drying and shaping to produce the finished ceramic fiber paperboard.

[0055] The physical properties of the ceramic fiber paperboard prepared in this embodiment are shown in Table 3: Table 3

[0056] Example 3 a) Immerse aluminum silicate fibers in a 12% hydrochloric acid solution for 8 hours to obtain aluminum silicate fibers with corroded surfaces.

[0057] b) After cleaning and drying the corroded aluminum silicate fibers, mix them with the modifier and stir to obtain aluminum silicate fibers coated with the modifier; the amount of modifier added is 8% of the mass of the corroded aluminum silicate fibers; the modifier ratio is alumina: high alumina bauxite clinker: zircon sand = 9: 0.5: 0.5.

[0058] c) The aluminosilicate fibers coated with the modifier are placed in a calcining furnace and calcined at 1100℃ for 30 minutes. Then, the calcined aluminosilicate fibers are taken out, cooled, and then screened and purified to remove fiber slag balls and other impurities, thus obtaining the modified aluminosilicate fibers.

[0059] d) The modified aluminosilicate fibers were prepared into an inorganic fiber slurry with a concentration of 0.03%. The dispersed slurry was pumped to a mixing tank, where 7.5% phenolic resin and 7.5% water glass were added to obtain a mixed slurry. The mixed slurry was then fed to the paperboard forming section of a wire paper machine to prepare wet ceramic fiber paperboard, which was then subjected to press drying and dewatering treatment to obtain the paperboard precursor.

[0060] e) The paperboard precursor is conveyed to the sizing section of the inclined wire paper machine, where adhesive impregnation is performed using a sizing device. The type and amount of adhesive are the same as those added to the pulp. After a pressing process to remove excess adhesive, the paperboard enters the drying section for drying and shaping to produce the finished ceramic fiber paperboard.

[0061] The physical properties of the ceramic fiber paperboard prepared in this embodiment are shown in Table 4: Table 4

[0062] Based on the physical property tests of ceramic fiber paperboard in Examples 1-3 above, it can be seen that Example 1 is a more optimized preparation scheme of the present application, and the ceramic fiber paperboard prepared by it has more balanced properties and the best overall performance.

[0063] Examples 2 and 3 are two types of ceramic fiber paperboards prepared using the two extreme values ​​of the parameters in this application. All their indicators meet the technical requirements of this application. However, compared with Example 1, the indicators are either too high or too low, and neither achieves a reasonable balance.

[0064] Comparative Example 1 Compared with Example 1, the difference is that the corrosion treatment in step a) was not performed, while the other steps are the same. The physical properties of the ceramic fiber paperboard prepared in this comparative example are shown in Table 5: Table 5

[0065] Comparative Example 2 Compared with Example 1, the difference is that the step of adding the modifier in step b) was not performed, while the other steps are the same. The physical properties of the ceramic fiber paperboard prepared in this comparative example are shown in Table 6: Table 6

[0066] Comparative Example 3 Compared with Example 1, the difference is that the calcination treatment in step c) was not performed, while the other steps are the same. The physical properties of the ceramic fiber paperboard prepared in this comparative example are shown in Table 7: Table 7

[0067] Comparative Example 4 Compared with Example 1, the difference is that no adhesive was added in step d), while the other steps are the same. The physical properties of the ceramic fiber paperboard prepared in this comparative example are shown in Table 8: Table 8

[0068] Comparative Example 5 Compared with Example 1, the difference is that the surface coating part was not dipped in resin in step e), while the other steps are the same. The physical properties of the ceramic fiber paperboard prepared in this comparative example are shown in Table 9: Table 9

[0069] Results analysis: In Comparative Example 1, no surface corrosion treatment was performed on the aluminum silicate fiber, which reduced the amount of modifier adhering to the fiber surface. This resulted in a decrease in the performance modification of the aluminum silicate fiber during calcination, and consequently, a reduction in all properties of the prepared ceramic fiber paperboard.

[0070] In Comparative Example 2, no modifier was added. During the calcination process, only the mullite phase of the aluminosilicate fiber was added, which increased the fiber's high-temperature resistance but also increased its brittleness and reduced its elasticity. This shows that adding a modifier is an important condition for increasing the fiber's elastic compressive strength and corrosion resistance.

[0071] In Comparative Example 3, no high-temperature calcination treatment was performed, which prevented the added modifier from modifying the fibers and also did not change the fiber crystal structure. As a result, the prepared paperboard had poor performance in all aspects, and some properties were lower than those of commercial products. Therefore, high-temperature calcination treatment is a necessary condition for fiber modification and reinforcement.

[0072] In Comparative Example 4, the absence of adhesive added to the pulp resulted in a significant reduction in the strength of the prepared liner paper. In particular, the fiberboard was relatively loose after molding. When the adhesive was impregnated in the sizing section, the low strength of the board caused a large amount of fiber to fall off, making it difficult to complete the adhesive impregnation process. Therefore, adding adhesive to the pulp is an important condition for improving the bonding strength of fiberboard.

[0073] In Comparative Example 5, the lack of adhesive impregnation in the sizing section resulted in a significant reduction in the strength of the prepared fiberboard. Simply adding adhesive to the pulp is insufficient to achieve the required strength after fiberboard formation. Impregnation in the sizing section effectively improves adhesive retention on the fiber surface, thereby enhancing the bond strength between fibers. This also improves the compressive strength and elasticity of the fiberboard.

[0074] Therefore, the ceramic fiber paperboard prepared by the series of preparation methods proposed in this application has excellent physical properties and can be used as a raw material to prepare the three-way catalytic converter liner layer for automobiles, as well as other applications in high temperature and high pressure fields, thereby expanding the application range of ceramic fiber paperboard and improving its applicability.

[0075] The above description is only a part or preferred embodiment of this application. Neither the text nor the drawings should limit the scope of protection of this application. All equivalent structural transformations made using the content of this application's specification and drawings under the overall concept of this application, or direct / indirect applications in other related technical fields, are included within the scope of protection of this application.

Claims

1. A method for preparing ceramic fiber paperboard, characterized in that, The preparation steps include the following: a) Immerse aluminum silicate fibers in an acidic solution with a concentration of 5% to 12% or an alkaline solution with a concentration of 10% to 16% for 4 to 8 hours to obtain aluminum silicate fibers with a corroded surface. b) The surface-corroded aluminosilicate fibers are mixed and stirred with a modifier to obtain aluminosilicate fibers coated with the modifier; wherein the mass of the modifier is 2% to 8% of the mass of the surface-corroded aluminosilicate fibers; the modifier is a mixture of alumina and inorganic materials, and the inorganic materials are one or more of high-alumina bauxite clinker, clay clinker, and zircon sand. c) The aluminum silicate fiber coated with the modifier is calcined and impurities are removed after cooling to obtain the modified aluminum silicate fiber. d) The modified aluminosilicate fiber is prepared into a slurry, and an adhesive is added and stirred to obtain a mixed slurry. A paperboard precursor is prepared based on the mixed slurry. e) The paperboard precursor is impregnated with adhesive to remove excess adhesive, and then dried and shaped to obtain the finished ceramic fiber paperboard.

2. The method for preparing ceramic fiber paperboard according to claim 1, characterized in that, The acidic solutions include hydrochloric acid solution, nitric acid solution, sulfuric acid solution, carbonic acid solution, and phosphoric acid solution; The alkaline solution includes magnesium hydroxide solution, calcium hydroxide solution, nickel hydroxide solution, and manganese hydroxide solution.

3. The method for preparing ceramic fiber paperboard according to claim 1, characterized in that, In step c), the calcination temperature is 900–1100°C; the calcination time is 10–30 min.

4. The method for preparing ceramic fiber paperboard according to claim 1, characterized in that, In step d), the concentration range of the slurry prepared from the modified aluminosilicate fiber is 0.02% to 0.05%.

5. The method for preparing ceramic fiber paperboard according to claim 1, characterized in that, In steps d) and e), the adhesive is a mixture of organic and inorganic adhesives, wherein the mass percentage of the organic adhesive to the inorganic adhesive is 1:

1.

6. The method for preparing ceramic fiber paperboard according to claim 5, characterized in that, The organic adhesive is one or more of phenolic resin, styrene-acrylic resin, polyvinyl acetate emulsion, and artificial latex; the inorganic adhesive is one or more of water glass, silica sol, polyaluminum chloride, aluminum chromium phosphate, aluminum sulfate, and aluminum phosphate.

7. The method for preparing ceramic fiber paperboard according to claim 6, characterized in that, In step d), the mass of the adhesive is 5% to 15% of the mass of the slurry.

8. A ceramic fiber paperboard, characterized in that, It is prepared by the method for preparing ceramic fiber paperboard as described in any one of claims 1 to 7.

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