A ceramic sintering aid and its application

Abstract

The present invention relates to the field of ceramic membrane technology, and in particular to a ceramic sintering aid and its application. The ceramic sintering aid, in parts by weight, comprises 2‑4 parts of manganese dioxide and 4‑8 parts of modified aluminum powder, the modified aluminum powder comprises aluminum particles, the surface of the aluminum particles is coated with an epoxy resin layer; the mass ratio of aluminum particles to epoxy resin is 2‑3:1. Based on the fact that low-valent manganese ions are not corrosion-resistant, the present invention improves the corrosion resistance of manganese ion-containing ceramics by coating ceramic particles with a corrosion-resistant layer. At the same time, the melting point of aluminum oxide is extremely high, and it is very difficult to form a coating layer. The present invention coats aluminum powder with resin, and the ceramic is sintered in an inert gas atmosphere. At high temperatures, the resin vaporizes, and the aluminum melts to form a liquid phase with good fluidity to coat the raw material particles; after cooling, it is changed to an air atmosphere, so that the aluminum liquid is oxidized to form a dense aluminum oxide layer, isolating the low-valent manganese oxides that are easily corroded by acid, so as to achieve high density and corrosion resistance of the ceramic.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramic membranes, and in particular to a ceramic sintering aid and application thereof. Background Art

[0002] The performance of honeycomb ceramic thermal storage body is an important indicator of RTO. The dense ceramic can provide better mechanical properties and can accommodate more heat per unit volume, which can effectively improve the life of the ceramic.

[0003] Prior art CN 107445627 B relates to a method for preparing a double-layered ceramic powder coated with a phenolic resin and manganese dioxide, comprising the following steps: (1) adding potassium permanganate to deionized water to form a homogeneous solution, and evenly distributing ceramic powder in the homogeneous solution; (2) dripping a manganese acetate solution into the mixed solution, filtering, drying, and sieving to obtain a MnO2-coated ceramic powder; (3) mixing the MnO2-coated ceramic powder with a phenolic resin, adding a sufficient amount of ethanol solvent, and rotary evaporating to a small amount of ethanol; (4) removing the composite powder, drying, grinding, and sieving to obtain a double-layered ceramic powder coated with a phenolic resin and manganese dioxide. This invention has a simple process, good coating effect, and low equipment requirements. It effectively solves the problems of uneven distribution of sintering aids in the matrix and uneven distribution of binders in the ceramic powder, and can effectively improve the sintering performance and mechanical properties of ceramic parts. However, its sintering aid manganese dioxide will reduce the acid corrosion resistance of the ceramic. At the same time, the co-precipitation method for preparing coating materials is complex and difficult to implement industrially.

[0004] Prior art CN 118459232 A discloses an alumina ceramic membrane sintering aid, a preparation method and application thereof, relating to the field of ceramic membrane technology. The alumina ceramic membrane sintering aid is composed of nano-silicon oxide and foaming powder. The foaming powder includes 20 parts of alumina powder, 5080 parts of potassium feldspar, 520 parts of sodium feldspar, 0.11 parts of sodium carboxymethyl cellulose, 0.11 parts of sodium tripolyphosphate, 0.53 parts of sodium hexametaphosphate, 0.31 parts of 1000 mesh manganese dioxide, 0.10.6 parts of 1000 mesh silicon carbide, and 100 parts of water. The alumina ceramic membrane sintering aid of this invention has controllable particle size and temperature control during the preparation of the alumina ceramic membrane support. During the preparation of the alumina ceramic membrane support, the nano-silica in the sintering aid can adjust the viscosity of the high-temperature liquid state and accelerate the reaction between the sintering aid and the alumina powder, providing a significant bridging effect. The porous liquid state at high temperatures can ensure the strength of the alumina ceramic membrane support while increasing its porosity. However, the manganese dioxide in the material can reduce the ceramic's acid corrosion resistance and make alumina sintering difficult. Summary of the Invention

[0005] The purpose of the present invention is to provide a ceramic sintering aid for improving the density and corrosion resistance of ceramics and its application.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A ceramic sintering aid comprises, by weight, 2-4 parts of manganese dioxide and 4-8 parts of modified aluminum powder, wherein the modified aluminum powder comprises aluminum particles, the surfaces of which are coated with an epoxy resin layer; and the mass ratio of the aluminum particles to the epoxy resin is 2-3:1.

[0008] The present invention promotes ceramic densification through the elemental solid solution of manganese ions, and at the same time utilizes the chemical stability of the alumina coating layer to isolate the corrosion source. However, due to the high melting point of alumina, the coating process is complicated. In the present invention, aluminum particles are used as the aluminum source to introduce alumina. Metallic aluminum has a low melting point, and high-temperature aluminum liquid has good fluidity and can spread on the surface of the particles, forming an aluminum liquid coating layer of the ceramic raw material during the sintering process. After cooling, the sample is exposed to the air to oxidize the aluminum to form an alumina coating layer. Since aluminum is relatively active, aluminum oxidation must be avoided before sintering, otherwise it will result in the inability to form aluminum liquid during the sintering process. Therefore, the present invention uses epoxy resin to coat aluminum powder, effectively isolating the air, thereby avoiding the oxidation of aluminum during the ceramic preparation process, ensuring that aluminum liquid can be formed to wrap the ceramic during the sintering process, and at the same time promoting the densification of the ceramic. The oxidized alumina layer plays a role in isolating the corrosion source.

[0009] In a preferred embodiment, the method for preparing the modified aluminum powder includes the following steps: uniformly dispersing aluminum particles and epoxy resin in a solvent, and drying to obtain the modified aluminum powder.

[0010] In a preferred embodiment, the added mass of the solvent is 4-9 times the mass of the solid.

[0011] Using anhydrous ethanol (ethyl acetate) as a solvent, aluminum particles and epoxy resin are dispersed into a 10wt%-20wt% solution, stirred under a magnetic stirrer for 30-60 minutes to prepare a dispersion, and then the dispersion is placed in a vacuum drying oven and solidified to obtain modified aluminum powder.

[0012] In a preferred embodiment, the drying time is 3-5 hours and the temperature is 50-70°C.

[0013] Too short a curing time will result in incomplete curing and poor surface quality; too long a curing time will cause the surface coating to become hard and brittle.

[0014] In a preferred embodiment, the solvent is ethanol or ethyl acetate.

[0015] In a preferred embodiment, the solvent is anhydrous ethanol or ethyl acetate.

[0016] Water has poor solubility for epoxy resin and reacts with aluminum particles, severely degrading ceramic performance. Solvents with high evaporation rates, such as acetone, can lead to uneven coating during the curing process. Anhydrous ethanol and ethyl acetate have good solubility for epoxy resin and moderate evaporation rates, resulting in a uniform coating.

[0017] In a preferred embodiment, the epoxy resin is bisphenol A epoxy resin.

[0018] In a preferred embodiment, the viscosity of the epoxy resin is 100-500 mPa·s.

[0019] If the viscosity is too high, it will be difficult to mix evenly with the aluminum powder; if the viscosity is too low, it will be difficult to effectively adhere to the surface of the aluminum powder.

[0020] In a preferred embodiment, the epoxy equivalent weight of the epoxy resin is 150-200 g / eq.

[0021] In a preferred embodiment, the particle size D50 of the modified aluminum powder is 5-10 μm, and the particle size distribution (D90D10) / D50≤3.0.

[0022] Based on the same inventive concept, the present invention provides the use of the ceramic sintering aid in the preparation of a honeycomb ceramic thermal storage body.

[0023] Based on the same inventive concept, the present invention provides a honeycomb ceramic heat storage body, comprising the ceramic sintering aid.

[0024] In one preferred embodiment, the honeycomb ceramic heat storage body further comprises: 40-60 parts of bauxite powder, 2-7 parts of cordierite powder, 1-4 parts of Suzhou kaolin, 0.5-1.5 parts of pyrope powder, 20-35 parts of mullite powder, 2-5 parts of potassium feldspar, 3-9 parts of raw talc; 0.2-0.5 parts of dispersant, and 0.5-0.2 parts of grinding aid.

[0025] In a preferred embodiment, the dispersant is sodium acrylate.

[0026] In a preferred embodiment, the grinding aid is glycerol.

[0027] In a preferred embodiment, the aluminum oxide content in the bauxite powder is greater than 80%.

[0028] Based on the same inventive concept, the present invention provides a method for preparing the honeycomb ceramic thermal storage body, comprising the following steps:

[0029] The raw materials except the ceramic sintering aid are mixed and ball-milled to obtain a mixture;

[0030] The mixed material, kneading agent and ceramic sintering aid are mixed and then kneaded, refined, molded and dried to obtain a dry blank;

[0031] The dry blank is sintered to obtain the honeycomb ceramic heat storage body.

[0032] In a preferred embodiment, the kneading agent includes 1-4 parts of cellulose, 1-3 parts of palm oil, and 0.3-1 part of polyethylene oxide.

[0033] In a preferred embodiment, the viscosity of the cellulose is 80,000-120,000; the melting point of palm oil is 24-28°; and the molecular weight of polyethylene oxide is 1,000,000-8,000,000.

[0034] In one preferred embodiment, the sintering process is as follows: in a nitrogen atmosphere, the temperature is raised to 850-950°C at a rate of 5-10°C / min, and then the temperature is raised to 1200-1300°C at a rate of 2-4°C / min, and kept warm for 2-3 hours; then the temperature is lowered, and the nitrogen atmosphere is maintained during the cooling process. When the temperature drops below 300°C, the nitrogen is stopped and the temperature is continued to cool to room temperature.

[0035] Kneading, refining, pressing and drying are all common steps and means for preparing honeycomb ceramic thermal storage bodies.

[0036] The beneficial effects of the present invention are:

[0037] The present invention has developed a sintering aid for highly dense, corrosion-resistant ceramic materials. The manganese dioxide and aluminum particles used are inexpensive, and ceramic samples sintered in a nitrogen atmosphere have extremely high density. The increased density comes from the elemental solid solution of the added manganese dioxide and the low-valent manganese ions decomposed at high temperatures with the ceramic matrix. The lattice distortion caused by the solid solution greatly increases the material diffusion rate, and the high-temperature liquid phase formed by the melting of aluminum powder in a nitrogen atmosphere can also promote mass transfer and fill pores, thereby obtaining a highly dense ceramic. However, low-valent manganese ions are not corrosion-resistant. The present invention improves the corrosion resistance of manganese ion-containing ceramics by coating the ceramic particles with a corrosion-resistant layer. Alumina has good chemical stability, but its melting point is extremely high, and it is very difficult to form a coating layer. Therefore, the present invention uses resin to coat aluminum powder to avoid oxidation of the aluminum powder during the treatment process before sintering; the modified aluminum powder is sintered in an inert gas atmosphere. At high temperatures, the resin vaporizes and the aluminum melts to form a liquid phase with good fluidity to wrap the raw material particles; after cooling, it is changed to an air atmosphere, so that the aluminum liquid oxidizes to form a dense aluminum oxide layer, isolating the low-valent manganese oxide that is easily corroded by acid, so as to achieve the high density and corrosion resistance of the prepared ceramic. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a flow chart for preparing the high-density, corrosion-resistant honeycomb ceramic according to Example 2 of the present invention. DETAILED DESCRIPTION

[0039] The present invention is not limited to the following specific embodiments. Those skilled in the art can implement the present invention in various other specific embodiments based on the content disclosed in the present invention. Any simple changes or modifications made to the design structure and ideas of the present invention fall within the scope of protection of the present invention. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other unless otherwise specified. Unless otherwise specified, the relevant percentages are weight percentages.

[0040] Example 1

[0041] Effect of Manganese Dioxide Addition Amount on Ceramics Properties

[0042] A high-density honeycomb ceramic thermal storage body comprises a base raw material powder and other components. The base raw material powder is composed of the following base raw materials by weight (kg): 55 parts of bauxite powder with an aluminum oxide content greater than 80%, 5 parts of cordierite powder, 2 parts of Suzhou kaolin, 0.5 parts of pyrope powder, 30 parts of mullite powder, 3.5 parts of potassium feldspar, and 4 parts of raw talc. Sodium acrylate as a dispersant is then added at a concentration of 5‰ of the total weight of the base raw material powder, along with glycerin as a grinding aid at a concentration of 2‰ of the total weight of the base raw material powder. Manganese dioxide is then added at concentrations of 0%, 2%, 4%, 6%, 8%, and 10% of the total weight of the base raw material, respectively. The performance of the samples is then tested.

[0043] The preparation method of the high-density honeycomb ceramic heat storage body is as follows:

[0044] Weigh each raw material by weight, put the raw materials into a ball mill, and ball mill at a speed of 30 revolutions per minute for 6 hours to obtain a mixture; add the mixture into a kneader, add 2% of 100,000 viscosity cellulose, 2% of 28-degree palm oil, 8‰ of 5 million molecular weight polyethylene oxide, and 13% of deionized water, set the kneader speed to 30 revolutions per minute, and knead for 20 minutes to obtain a kneaded mud segment; put the kneaded mud segment into a vacuum mud kneading machine, and refine it at a vacuum degree of 0.07 to obtain a refined mud segment; use a mold to press it into the desired product to obtain a wet blank; dry the wet blank to obtain a dry blank; cut both ends of the dry blank, and the cutting size is 1.20 times the length of the finished product to obtain a cut dry blank; put the cut dry blank into a kiln, heat it to 900°C at a rate of 5°C / min, and then heat it to 1250°C at a rate of 3°C / min, and keep it warm for two hours.

[0045] Measure the true density, sintering line shrinkage, water absorption and thermal expansion coefficient of the sample. The specific test method is as follows:

[0046] The true density test method is implemented in accordance with the national standard GB / T 24203-2024.

[0047] The thermal expansion coefficient test method is implemented in accordance with the national standard GB / T 16920-2015.

[0048] The calculation method of sintering line shrinkage is:

[0049] Wherein, L% is the sintering linear shrinkage; L1 is the length of the sample before sintering; L2 is the length of the sample after sintering.

[0050] The water absorption rate is calculated as follows:

[0051] Among them, M% is the water absorption rate; M1 is the mass before water absorption; M2 is the mass after water absorption.

[0052] The sample was then immersed in a 28% sodium hydroxide solution and magnetically stirred at 25° C. for 96 hours, and the mass loss rate of the sample was measured.

[0053] The sample was immersed in a 50% dilute sulfuric acid solution and magnetically stirred at 25°C for 96 hours. After drying, the mass loss rate of the sample was measured to characterize the acid and alkali corrosion resistance of the sample.

[0054] The test results are shown in Table 1.

[0055] Table 1 Effect of different contents of manganese dioxide on ceramic properties

[0056]

[0057] It can be seen from Table 1 that with the increase of manganese dioxide addition, the true density of the sample gradually increases. When the addition amount reaches 4wt%, the true density of the sample reaches the maximum, and when the addition amount is 6wt%, the true density of the ceramic decreases rapidly.

[0058] In terms of sintering line shrinkage and water absorption, increasing manganese dioxide addition increases shrinkage and decreases water absorption. When the manganese dioxide addition reaches 6wt%, the ceramic volume shrinks further compared to the 4wt% addition, but the true density is significantly lower than when the addition is 4wt%. This decrease in true density despite volume shrinkage may be due to, on the one hand, changes in the ceramic phase and content caused by changes in manganese dioxide addition, and, on the other hand, the decomposition of manganese dioxide into low-valent manganese oxides and oxygen at high temperatures. The released oxygen results in a mass loss, resulting in a decrease in true density despite the volume shrinkage.

[0059] Judging from the weight loss rate after acid-base treatment, with the increase of manganese dioxide, the alkali resistance of the ceramic increases, reaching the highest at 4wt%, and then the alkali resistance decreases due to the increase of glass phase content in the ceramic; with the increase of manganese dioxide, the acid resistance of the ceramic gradually weakens. Manganese dioxide itself is insoluble in cold sulfuric acid. The weakening of acid resistance is due to the increase of glass phase on the one hand, and the decomposition of manganese dioxide into low-valent manganese oxide at high temperature on the other hand. Low-valent manganese oxide is soluble in most inorganic acids. Therefore, the weight loss rate of the ceramic in dilute sulfuric acid solution gradually increases.

[0060] From the perspective of thermal expansion coefficient, the increase in thermal expansion coefficient of ceramics with the addition of 2wt% and 4wt% manganese dioxide is small, indicating that manganese dioxide promotes the production of less liquid phase. When the manganese dioxide addition amount is 6wt%, the thermal expansion coefficient of ceramics increases significantly, which is because excessive addition of manganese dioxide leads to a large amount of liquid phase generated.

[0061] When the manganese dioxide addition exceeds 6%, the ceramic sample exhibits "bubbling" and sharply deteriorates the ceramic surface morphology. Therefore, the addition of manganese dioxide should not be too high. When the addition is 4%, the sample density is high and the thermal expansion coefficient increases slightly. However, the acid resistance of the sample with the addition of manganese dioxide deteriorates because low-valent manganese ions easily react with acid. To improve the corrosion resistance of manganese-containing ceramics, the present invention considers adding aluminum powder in the form of a composite to form an in-situ aluminum oxide coating, utilizing the excellent chemical stability of aluminum oxide to improve the problem of reduced acid resistance caused by manganese ions.

[0062] Example 2

[0063] Effect of 4% manganese dioxide + different contents of aluminum powder on ceramic properties

[0064] according to Figure 1 The process shown is for preparing a high-density, corrosion-resistant ceramic material, including basic raw material powder and other components. The basic raw material powder is composed of the following raw materials in parts by weight (kg): 55 parts of bauxite powder with an aluminum oxide content >80%, 5 parts of cordierite powder, 2 parts of Suzhou kaolin, 0.5 parts of pyrope powder, 30 parts of mullite powder, 3.5 parts of potassium feldspar, 4 parts of raw talc, 5‰ of the total mass of the basic raw material powder as a dispersant, 2‰ of the total mass of the basic raw material powder as a grinding aid, and 4wt% of manganese dioxide as a total mass of the basic raw material powder.

[0065] The raw materials are weighed by weight, placed in a ball mill, and ball-milled at a speed of 30 revolutions per minute for 6 hours to prepare a mixture; aluminum particles are dispersed in anhydrous ethanol to prepare a dispersion with a solid content of 40-60wt%, and an epoxy resin accounting for one-third of the mass of the aluminum particles is dissolved in the anhydrous ethanol, wherein the epoxy resin is a bisphenol A-type epoxy resin with a viscosity of 400mPa·s and an epoxy equivalent of 150g / eq; the mixture is stirred under a magnetic stirrer for 30 minutes; and the dispersion is placed in a vacuum drying oven at a temperature of 60°C for 4 hours to obtain organic-coated modified aluminum powder. The mixture was added to a kneader, followed by 2% by weight of 100,000 viscosity cellulose, 2% of 28-degree palm oil, 8‰ of 5,000,000 molecular weight polyethylene oxide, 13% of deionized water, and the aforementioned amount of modified aluminum powder. The kneader was set to 30 rpm and kneaded for 20 minutes to produce a kneaded clay segment. The kneaded clay segment was then placed in a vacuum kneader and refined at a vacuum of 0.07 to produce a refined clay segment. The resulting product was then pressed into a mold to produce a wet billet. The wet billet was then dried in a vacuum drying oven at 125°C for 4 hours to produce a dry billet. The dry billet was then placed in a kiln and heated at a rate of 5°C / min to 900°C, then at a rate of 3°C / min to 1250°C, under a nitrogen atmosphere, and maintained at this temperature for two hours. During the cooling process, the nitrogen atmosphere was maintained as the kiln cooled. When the temperature dropped to approximately 300°C, the nitrogen flow was stopped, and the sample was exposed to air to produce a test specimen.

[0066] Measure the true density, sintering line shrinkage, water absorption and thermal expansion coefficient of the sample. The specific test method is the same as above.

[0067] The sample was immersed in 28% sodium hydroxide solution and magnetically stirred at 25°C for 96 hours, and the mass loss rate of the sample was measured;

[0068] The sample was immersed in a 50% dilute sulfuric acid solution and magnetically stirred at 25°C for 96 hours. After drying, the mass loss rate of the sample was measured to characterize the acid and alkali corrosion resistance of the sample.

[0069] The test results are shown in Table 2.

[0070] Table 2 Effects of 4% manganese dioxide + modified aluminum powder with different contents on ceramic properties

[0071]

[0072] Adding 2, 4, 6, 8, and 10% modified aluminum powder to a 4% manganese dioxide addition resulted in a ceramic density that initially increased and then decreased. This is because the modified aluminum powder in a nitrogen atmosphere forms a liquid phase at high temperatures, promoting mass transfer and filling pores. When the ceramic sample is cooled to approximately 300°C after sintering and exposed to air, aluminum oxidation causes a certain volume expansion. Within a certain range, compressive stress is present in the ceramic matrix, which enhances the toughness of the ceramic. However, as the modified aluminum powder addition increases, excessive expansion leads to a decrease in ceramic density. With increasing modified aluminum powder addition, the ceramic's acid and alkali corrosion resistance initially increases and then decreases. This improvement in corrosion resistance suggests that the strategy of forming a liquid phase at high temperature and then oxidizing in air after cooling can effectively isolate corrosive substances. However, as the modified aluminum powder addition increases, the ceramic density decreases. When the addition exceeds 6%, the sample's weight loss in acid and alkali solutions increases. Therefore, the appropriate modified aluminum powder addition level is 4-8%.

[0073] Example 3

[0074] Effect of epoxy resin addition on ceramic properties,

[0075] The difference between this embodiment and embodiment 2 is that the addition amount of modified aluminum powder is fixed at 6%, and the proportion of epoxy resin is changed. The properties of the prepared ceramic samples are shown in Table 3.

[0076] Table 3 Effects of different ratios of modified aluminum powder and epoxy resin on ceramic properties

[0077]

[0078] When the ratio of aluminum particles to epoxy resin is 2-3:1 (especially 3:1, that is, the epoxy resin mass accounts for 1 / 4-1 / 3), the ceramic density and corrosion resistance reach their peak. The possible reason is that too little epoxy resin cannot play the role of coating the aluminum powder, resulting in oxidation of part of the aluminum powder and poor sintering density of the ceramic; too much epoxy resin will cause excessive gas produced after the decomposition of organic matter, acting as a pore-forming agent. The pores inside the ceramic sample increase the contact area between the sample and the corrosion source. The same amount of aluminum powder added has limited isolation effect, which also leads to a decrease in corrosion resistance.

[0079] Example 4

[0080] The effects of different solvents on ceramic properties were investigated. This example differs from Example 2 in that the modified aluminum powder addition level was fixed at 6% and the epoxy resin addition level was one-third of the aluminum powder mass. The effects of different solvents on ceramic properties were investigated. The properties of the ceramic samples produced using different solvents are shown in Table 4.

[0081] Table 4 Effects of different solvents on ceramic properties

[0082]

[0083]

[0084] Due to the different solvents' different solubility for epoxy resin and their different volatility, the effects of different solvents on the quality of the organic coating layer vary significantly. Pure water has poor solubility for epoxy resin and reacts with aluminum powder, causing aluminum powder oxidation, and is basically unable to provide effective performance improvement for the ceramic. Acetone has a high volatilization rate and may cause cracking of the organic coating layer during the ceramic drying process. Anhydrous ethanol and ethyl acetate have better solubility for epoxy resin and their volatilization rates are moderate, which can effectively control the drying and curing rate. In the present invention, the solvent should be anhydrous ethanol or ethyl acetate.

[0085] Example 5

[0086] Effects of different organic coating materials on ceramic properties

[0087] The difference between this embodiment and embodiment 2 is that the addition amount of modified aluminum powder is 6% of the base powder, and phenolic resin is used instead of epoxy resin. The effects of different coating materials on ceramic properties are shown in Table 5.

[0088] Table 5 Effects of different organic coating materials on ceramic properties

[0089]

[0090] The phenolic resin was purchased from the market and was the same as that in the prior art CN 107445627 B.

[0091] The main function of the coating organic matter is to wrap the aluminum powder to prevent it from oxidizing during the ceramic preparation process. Ultimately, it will be sintered and decomposed in a nitrogen atmosphere. Different coating materials have different effects on the performance of the ceramic.

[0092] It should be noted that the above embodiments are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. A person skilled in the art would be able to make other variations or modifications based on the above description. It is not possible to enumerate all embodiments here. Any obvious variations or modifications arising from the technical solution of the present invention remain within the scope of protection of the present invention.

Claims

1. A ceramic sintering aid, characterized in that: The invention comprises, by weight, 2-4 parts of manganese dioxide and 4-8 parts of modified aluminum powder, wherein the modified aluminum powder comprises aluminum particles, the surface of which is coated with an epoxy resin layer; the mass ratio of the aluminum particles to the epoxy resin is 2-3:1; The preparation method of the modified aluminum powder comprises the following steps: uniformly dispersing aluminum particles and epoxy resin in a solvent, and drying to obtain the modified aluminum powder; the solvent is anhydrous ethanol or ethyl acetate.

2. The ceramic sintering aid according to claim 1, characterized in that The added mass of the solvent is 4-9 times the mass of the solid; the drying time is 3-5 hours, and the temperature is 50-70°C.

3. The ceramic sintering aid according to any one of claims 1 to 2, characterized in that: The epoxy resin is bisphenol A epoxy resin; the particle size D50 of the modified aluminum powder is 5-10 μm.

4. A honeycomb ceramic heat storage body, characterized in that: The ceramic sintering aid comprises the ceramic sintering aid according to any one of claims 1 to 3.

5. The honeycomb ceramic heat storage body according to claim 4, characterized in that: The honeycomb ceramic heat storage body includes, by mass, 6-12 parts of ceramic sintering aid, 40-60 parts of bauxite powder, 2-7 parts of cordierite powder, 1-4 parts of Suzhou kaolin, 0.5-1.5 parts of pyrope powder, 20-35 parts of mullite powder, 2-5 parts of potassium feldspar, and 3-9 parts of raw talc; 0.2-0.5 parts of dispersant, and 0.5-0.2 parts of grinding aid.

6. The honeycomb ceramic heat storage body according to claim 5, characterized in that: The dispersant is sodium acrylate; the grinding aid is glycerol; and the aluminum oxide content in the bauxite powder is greater than 80%.

7. A method for preparing the honeycomb ceramic thermal storage body according to any one of claims 4 to 6, characterized in that: The following steps are involved: The raw materials except the ceramic sintering aid are mixed and ball-milled to obtain a mixture; The mixed material, kneading agent and ceramic sintering aid are mixed and then kneaded, refined, molded and dried to obtain a dry blank; The dry blank is sintered to obtain the honeycomb ceramic heat storage body.

8. The method according to claim 7, characterized in that The kneading agent comprises 1-4 parts of cellulose, 1-3 parts of palm oil, and 0.3-1 part of polyethylene oxide; the viscosity of the cellulose is 80,000-120,000; the melting point of the palm oil is 24-28° C.; and the molecular weight of the polyethylene oxide is 1 million-8 million.

9. The method according to claim 7, characterized in that The sintering process is as follows: in a nitrogen atmosphere, heating to 850-950°C at a rate of 5-10°C / min, then heating to 1200-1300°C at a rate of 2-4°C / min, and keeping warm for 2-3 hours; then cooling, maintaining a nitrogen atmosphere during the cooling process, stopping the nitrogen flow when the temperature drops below 300°C, and continuing to cool to room temperature.

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