A kind of refractory material containing bauxite and preparation method thereof

Abstract

The present invention provides a refractory material containing bauxite and a preparation method thereof, and relates to the technical field of fireproof materials. The refractory material containing bauxite of the present invention is prepared from the following raw materials in parts by weight: 60-66 parts of bauxite, 8-10 parts of basalt fiber, 3-5 parts of silicon carbide, 10-14 parts of silicon dioxide powder, 6-10 parts of modified phenolic resin binder, 22-26 parts of ethanol, and 16-20 parts of water; the particle size of the bauxite is 240-300 mesh; the particle size of the silicon carbide is 50-100 mesh; the particle size of the silicon dioxide powder is 1000-1200 mesh; the diameter of the basalt fiber is 10-15 μm, and the length is 0.5-1 mm. The refractory material containing bauxite of the present invention can significantly improve the refractoriness and thermal stability of castings by optimizing its composition and performance.

Description

Technical Field

[0001] The invention relates to the technical field of fireproof materials, and in particular to a refractory material containing bauxite and a preparation method thereof. Background Art

[0002] Refractory materials are indispensable key materials in high-temperature industries and are widely used in metallurgy, building materials, chemical industry, electric power and other fields. With the continuous advancement of industrial technology, the requirements for high-temperature performance, chemical stability, mechanical strength and other aspects of refractory materials are increasing day by day. Bauxite, as a mineral resource rich in aluminum oxide, has become an important raw material for the preparation of high-performance refractory materials due to its unique physical and chemical properties.

[0003] Bauxite, also known as high-alumina bauxite, is a clay ore rich in aluminum oxide (Al2O3). my country has abundant bauxite resources, but the traditional production method is mainly based on calcining natural blocks, which has problems such as single variety, large quality fluctuations, poor resource utilization, high energy consumption and serious pollution. At the same time, excessive mining has led to the increasing scarcity of high-aluminum rich ore resources, and there is an urgent need to develop efficient and environmentally friendly preparation technologies.

[0004] Investment casting, also known as lost wax casting, is an ancient and complex casting process widely used in aviation, aerospace, precision machinery and other fields. This process involves making a fusible wax pattern, coating its surface with multiple layers of refractory coating to form a refractory shell, then heating and melting the wax pattern and pouring molten metal to finally obtain a high-precision, complex-shaped casting. In the investment casting process, the performance of the refractory coating is directly related to the quality and precision of the casting.

[0005] Investment casting requires refractory coatings to have extremely high refractoriness and thermal stability to withstand the high temperature during molten metal pouring and the rapid temperature changes during rapid cooling. During the investment casting process, the refractory coating needs to maintain a certain structural strength to prevent cracking or peeling during pouring and cooling. Based on this, the present invention provides a refractory material containing bauxite and a preparation method thereof. Summary of the invention

[0006] The purpose of the present invention is to provide a refractory material containing bauxite and a preparation method thereof, which optimizes the refractoriness and thermal stability of the refractory material, and also improves the stability of the material to prevent cracking.

[0007] On the one hand, the present invention provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight: 60-66 parts of bauxite, 8-10 parts of basalt fiber, 3-5 parts of silicon carbide, 10-14 parts of silicon dioxide powder, 6-10 parts of modified phenolic resin binder, 22-26 parts of ethanol, and 16-20 parts of water.

[0008] As the main component of refractory materials, bauxite has a high melting point and high thermal stability, and can maintain structural stability at high temperatures. When its particle size is 240-300 mesh, it not only ensures sufficient contact area between particles, but also facilitates mass transfer and densification during sintering.

[0009] Silicon carbide is a material with high melting point, high hardness and excellent high temperature resistance. When its particle size is 50-100 mesh, it can be used as a skeleton material to enhance the overall strength and refractoriness of refractory materials.

[0010] The high SiO2 content and fine particle size in silica powder enable the silica powder to fill the gaps between particles, increase the density of the material, and further improve the refractoriness and thermal stability.

[0011] Basalt fiber has good high temperature resistance and thermal stability, and can maintain its fiber shape at high temperatures to prevent the material from cracking due to thermal stress. At the same time, the addition of fiber can also increase the toughness and impact resistance of the material.

[0012] Furthermore, the raw material composition of the bauxite in parts by weight is: Al2O3: 70-74%, SiO2: 3-6%, TiO2: 1.5-2.5%, Fe2O3: 1.5-2% and others.

[0013] Furthermore, the particle size of the bauxite is 240-300 mesh; the particle size of the silicon carbide is 50-100 mesh.

[0014] Furthermore, the raw material composition of the silica powder by weight is: SiO2: 65-69%, Al2O3: 12-16%, CaO: 1-2%, MgO: 0.5-1.5% and others; the particle size of the silica powder is 1000-1200 mesh, and the compressive strength is 1000-2000kg / cm 2 , Shore hardness is 72-80Hs, specific surface area is 5.5-6.5m 2 / g, elastic modulus is 2.1-2.5×10 6 kg / cm 3 .

[0015] Furthermore, the basalt fiber has a diameter of 10-15 μm and a length of 0.5-1 mm.

[0016] Furthermore, the preparation method of the modified phenolic resin includes: mixing phenol, NaOH and water, heating at a temperature of 55-65°C for 10-12 minutes, adding formaldehyde solution when the temperature rises to 80-90°C, reacting for 60-70 minutes, adding lignin sulfonate, reacting at 88-92°C for 2.4-3 hours, then adding bentonite while maintaining the temperature and continuing to stir for 60-70 minutes, and then cooling to obtain the modified phenolic resin.

[0017] Furthermore, the weight ratio of the phenol, NaOH, water, formaldehyde, lignin sulfonate and bentonite is (24-28): (5-9): (65-75): (60-64): (10-12).

[0018] Furthermore, the mass concentration of the formaldehyde solution is 60-64%.

[0019] On the other hand, the present invention also provides a method for preparing a refractory material containing bauxite, the steps comprising:

[0020] (1) mixing bauxite, basalt fiber, silicon carbide, silicon dioxide powder and water to obtain a mixture A;

[0021] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0022] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0023] The beneficial effects of the present invention are:

[0024] When bauxite, basalt fiber, silicon carbide and silicon dioxide powder are selected for compounding in the present invention, each of these materials has a unique property, and the synergistic effect between them makes the compounded refractory material perform well in terms of refractoriness, thermal stability, and cracking prevention. Among them, the different particle size combinations of bauxite, silicon carbide and silicon dioxide powder form a good particle size distribution, which is conducive to the close stacking between particles and mass transfer during the sintering process, and reduces the cracking caused by uneven sintering. And the addition of basalt fiber plays a "bridge" role, connecting particles of different particle sizes, enhancing the integrity and toughness of the material, and effectively preventing the cracking caused by thermal stress concentration. The cooperation between them each constitutes an excellent base material for refractory materials, and other raw materials can also be added on the basis of these materials to further improve the material properties.

[0025] The present invention selects silica powder with a particle size of 1000-1200 mesh, which belongs to ultrafine powder, has a large specific surface area, is conducive to the close packing between particles and mass transfer during sintering, improves the density and strength of the material, and its own characteristics can improve the performance of refractory materials, wherein it also has a high content of SiO2 and an appropriate amount of Al2O3 to form stable silicate and aluminosilicate structures, which are not easy to decompose at high temperatures, thereby improving the refractoriness and thermal stability of refractory materials. And the fine particle size and moderate alkaline oxide content help to reduce the shrinkage and thermal stress of the material during sintering, thereby reducing the risk of cracking. When it is compounded with bauxite, particles of different particle sizes can form a more compact stacking structure when mixed, reduce porosity, improve the density and strength of the material, and the fine silica powder can promote the sintering reaction between bauxite particles, accelerate the densification process, and reduce the defects caused by uneven sintering.

[0026] The preparation method of the modified phenolic resin in the present invention is to first modify the phenolic resin with lignin and then use bentonite for compound modification. First, the phenolic resin can undergo a cross-linking reaction at high temperature. The active groups of lignin, such as hydroxyl and aldehyde groups, participate in the reaction to introduce larger substituent groups into the resin. The relative molecular mass of the reaction product gradually increases, and gradually cross-links to form a macromolecular network structure. This structure has high thermal stability and mechanical strength, and can withstand thermal stress and mechanical stress at high temperatures. Therefore, the lignin-modified phenolic resin is used as an adhesive. Its thermohardness characteristics enable the refractory material to maintain a high strength at high temperatures, and it is not easy to soften or deform. While improving the performance, it can also reduce the cost of the phenolic resin; and because of the characteristics of bentonite itself, its addition can enhance the refractory performance of the refractory material. At the same time, the compound modification of lignin and bentonite can achieve the stability of its crystal structure at high temperatures, and it is not easy to undergo phase change or decomposition, thereby maintaining the overall stability of the refractory material.

[0027] The mixed use of lignin modified phenolic resin and bentonite in the present invention can improve the microstructure of refractory materials, reduce internal defects and stress concentration points, and effectively prevent cracking. Lignin modified phenolic resin can form a uniform cross-linked network during the curing process, fill the micropores and cracks in the refractory materials, and improve the compactness and strength of the material. And bentonite has good expansibility and filling properties, and can form a fine filling layer in the refractory materials, further reducing internal defects and stress concentration points. The two work together so that the refractory materials can expand and contract evenly during the heating process, reducing the cracking phenomenon caused by uneven thermal stress. In addition, by experimental comparison, the modified phenolic resin obtained after the composite modification of bentonite and lignin to phenolic resin has a greater performance impact on refractory materials relative to bentonite directly as a raw material.

[0028] The modified phenolic resin in the present invention can solve the problem of poor high-temperature stability of bauxite to a certain extent when used in combination with bauxite; the modified phenolic resin as a binder contains a variety of active groups (such as hydroxyl, carboxyl, etc.) on its molecular chain, and these groups can chemically react or physically adsorb with hydroxyl or other functional groups on the surface of bauxite to form a strong chemical bond or physical bond. This bonding force not only enhances the interaction between bauxite particles, but also makes the entire refractory material structure more compact and stable. At high temperatures, this bonding force can resist the destruction of thermal stress and maintain the integrity of the material.

[0029] Furthermore, this modified phenolic resin with a three-dimensional network structure can form a dense protective film on the surface of bauxite particles. This protective film can block the erosion of bauxite by high-temperature gases and melts, and reduce the decomposition and phase change of bauxite at high temperatures. At the same time, the protective film can also reduce the direct contact between bauxite particles and reduce the thermal stress caused by the mismatch of thermal expansion coefficients. In addition, the modified phenolic resin also acts as a protective film on the surface of other raw materials to a certain extent, further improving the overall performance of refractory materials. DETAILED DESCRIPTION

[0030] The technical scheme of the present invention is described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. It should be noted that the raw materials can be obtained commercially.

[0031] Example 1

[0032] The present embodiment provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight: 63 parts of bauxite, 9 parts of basalt fiber, 4 parts of silicon carbide, 12 parts of silicon dioxide powder, 8 parts of modified phenolic resin binder, 24 parts of ethanol, and 18 parts of water;

[0033] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0034] In other embodiments, the raw material composition of bauxite by weight may also be: Al2O3: 70-74%, SiO2: 3-6%, TiO2: 1.5-2.5%, Fe2O3: 1.5-2% and any other interval values ​​may be taken.

[0035] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0036] In other embodiments, the particle size of bauxite can be any value in the range of 240-300 mesh, the particle size of silicon carbide can be any value in the range of 50-100 mesh; the diameter of basalt fiber is any value in the range of 10-15 μm, and the length is any value in the range of 0.5-1 mm.

[0037] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 1100 mesh, and the compressive strength is 1500kg / cm 2 , Shore hardness is 76Hs, specific surface area is 6m 2 / g, elastic modulus is 2.3×10 6 kg / cm 3 .

[0038] In other embodiments, the weight percentage of raw materials in the silica powder is: SiO2: 65-69%, Al2O3: 12-16%, CaO: 1-2%, MgO: 0.5-1.5% and all other interval values ​​can be any value; the particle size of the silica powder is any value between 1000-1200 mesh. After testing, the compressive strength of the silica powder is 1000-2000kg / cm 2 , Shore hardness is 72-80Hs, specific surface area is 5.5-6.5m 2 / g, elastic modulus is 2.1-2.5×10 6 kg / cm 3 .

[0039] The preparation method of the modified phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 60°C for 11 minutes, adding a formaldehyde solution with a mass concentration of 62% when the temperature reaches 85°C, reacting for 65 minutes, adding lignin sulfonate, reacting at 90°C for 2.7 hours, then adding bentonite while maintaining the temperature and continuing to stir for 65 minutes, and then cooling to obtain the modified phenolic resin; the weight ratio of phenol, NaOH, water, formaldehyde, lignin sulfonate and bentonite is 26:7:70:62:11.

[0040] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0041] (1) mixing bauxite, basalt fiber, silicon carbide, silicon dioxide powder and water to obtain a mixture A;

[0042] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0043] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0044] Example 2

[0045] The present embodiment provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight: 60 parts of bauxite, 8 parts of basalt fiber, 3 parts of silicon carbide, 10 parts of silicon dioxide powder, 6 parts of modified phenolic resin binder, 22 parts of ethanol, and 16 parts of water;

[0046] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0047] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0048] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 1100 mesh, and the compressive strength is 1500kg / cm 2 , Shore hardness is 76Hs, specific surface area is 6m 2 / g, elastic modulus is 2.3×10 6 kg / cm 3 .

[0049] The preparation method of the modified phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 55°C for 10 minutes, adding a formaldehyde solution with a mass concentration of 60% when the temperature reaches 80°C, reacting for 60 minutes, adding lignin sulfonate, reacting at 88°C for 2.4 hours, then adding bentonite while maintaining the temperature and continuing to stir for 60 minutes, and then cooling to obtain the modified phenolic resin; the weight ratio of phenol, NaOH, water, formaldehyde, lignin sulfonate and bentonite is 24:5:65:60:10.

[0050] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0051] (1) mixing bauxite, basalt fiber, silicon carbide, silicon dioxide powder and water to obtain a mixture A;

[0052] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0053] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0054] Example 3

[0055] The present embodiment provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight: 66 parts of bauxite, 10 parts of basalt fiber, 5 parts of silicon carbide, 14 parts of silicon dioxide powder, 10 parts of modified phenolic resin binder, 26 parts of ethanol, and 20 parts of water;

[0056] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0057] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0058] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 1100 mesh, and the compressive strength is 1500kg / cm 2 , Shore hardness is 76Hs, specific surface area is 6m 2 / g, elastic modulus is 2.3×10 6 kg / cm 3 .

[0059] The preparation method of the modified phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 65°C for 12 minutes, adding a formaldehyde solution with a mass concentration of 64% when the temperature reaches 90°C, reacting for 70 minutes, adding lignin sulfonate, reacting for 3 hours at 92°C, then adding bentonite while maintaining the temperature and continuing to stir for 70 minutes, and then cooling to obtain the modified phenolic resin; the weight ratio of phenol, NaOH, water, formaldehyde, lignin sulfonate and bentonite is 28:9:75:64:12.

[0060] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0061] (1) mixing bauxite, basalt fiber, silicon carbide, silicon dioxide powder and water to obtain a mixture A;

[0062] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0063] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0064] Example 4

[0065] The present embodiment provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight: 60 parts of bauxite, 10 parts of basalt fiber, 3 parts of silicon carbide, 14 parts of silicon dioxide powder, 6 parts of modified phenolic resin binder, 26 parts of ethanol, and 16 parts of water;

[0066] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0067] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0068] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 1100 mesh, and the compressive strength is 1500kg / cm 2 , Shore hardness is 76Hs, specific surface area is 6m 2 / g, elastic modulus is 2.3×10 6 kg / cm 3 .

[0069] The preparation method of the modified phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 65°C for 10 minutes, adding a formaldehyde solution with a mass concentration of 60% when the temperature reaches 90°C, reacting for 60 minutes, adding lignin sulfonate, reacting at 92°C for 2.4 hours, then adding bentonite while maintaining the temperature and continuing to stir for 70 minutes, and then cooling to obtain the modified phenolic resin; the weight ratio of phenol, NaOH, water, formaldehyde, lignin sulfonate and bentonite is 24:9:65:64:10.

[0070] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0071] (1) mixing bauxite, basalt fiber, silicon carbide, silicon dioxide powder and water to obtain a mixture A;

[0072] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0073] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0074] Comparative Example 1

[0075] This comparative example provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight:

[0076] 63 parts of bauxite, 9 parts of basalt fiber, 4 parts of silicon carbide, 12 parts of silicon dioxide powder, 8 parts of modified phenolic resin binder, 24 parts of ethanol, and 18 parts of water;

[0077] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0078] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0079] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 1100 mesh, and the compressive strength is 1500kg / cm 2 , Shore hardness is 76Hs, specific surface area is 6m 2 / g, elastic modulus is 2.3×10 6 kg / cm 3 .

[0080] The preparation method of the modified phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 60°C for 11 minutes, adding a formaldehyde solution with a mass concentration of 62% when the temperature reaches 85°C, reacting for 65 minutes, adding lignin sulfonate, reacting at 90°C for 2.7 hours, then maintaining the temperature and stirring for 65 minutes, and cooling to obtain the modified phenolic resin; the weight ratio of phenol, NaOH, water, formaldehyde and lignin sulfonate is 26:7:70:62.

[0081] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0082] (1) mixing bauxite, basalt fiber, silicon carbide, silicon dioxide powder and water to obtain a mixture A;

[0083] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0084] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0085] Comparative Example 2

[0086] This comparative example provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight:

[0087] 63 parts of bauxite, 9 parts of basalt fiber, 4 parts of silicon carbide, 12 parts of silicon dioxide powder, 8 parts of modified phenolic resin binder, 24 parts of ethanol, and 18 parts of water;

[0088] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0089] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0090] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 1100 mesh, and the compressive strength is 1500kg / cm 2 , Shore hardness is 76Hs, specific surface area is 6m 2 / g, elastic modulus is 2.3×10 6 kg / cm 3 .

[0091] The preparation method of the modified phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 60°C for 11 minutes, adding a formaldehyde solution with a mass concentration of 62% when the temperature reaches 85°C, reacting for 65 minutes, adding lignin sulfonate, reacting at 90°C for 2.7 hours, then maintaining the temperature and stirring for 65 minutes, and cooling to obtain the modified phenolic resin; the weight ratio of phenol, NaOH, water, formaldehyde and lignin sulfonate is 26:7:70:62.

[0092] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0093] (1) Bauxite, basalt fiber, silicon carbide, silicon dioxide powder, bentonite and water are mixed and stirred to obtain a mixture A; wherein the weight ratio of the lignin sulfonate to the bentonite is 62:11.

[0094] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0095] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0096] Comparative Example 3

[0097] This comparative example provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight:

[0098] 63 parts of bauxite, 9 parts of basalt fiber, 4 parts of silicon carbide, 12 parts of silicon dioxide powder, 8 parts of phenolic resin binder, 24 parts of ethanol, and 18 parts of water;

[0099] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0100] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0101] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 1100 mesh, and the compressive strength is 1500kg / cm 2 , Shore hardness is 76Hs, specific surface area is 6m 2 / g, elastic modulus is 2.3×10 6 kg / cm 3 .

[0102] The preparation method of the phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 60°C for 11 minutes, adding a formaldehyde solution with a mass concentration of 62% when the temperature reaches 85°C, reacting for 65 minutes, and cooling to obtain the phenolic resin; the weight ratio of the phenol, NaOH, water and formaldehyde is 26:7:70.

[0103] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0104] (1) mixing bauxite, basalt fiber, silicon carbide, silicon dioxide powder, bentonite and water to obtain a mixture A, wherein the weight ratio of phenol to bentonite is 26:11;

[0105] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0106] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0107] Comparative Example 4

[0108] This comparative example provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight:

[0109] 63 parts of bauxite, 9 parts of basalt fiber, 4 parts of silicon carbide, 12 parts of silicon dioxide powder, 8 parts of phenolic resin binder, 24 parts of ethanol, and 18 parts of water;

[0110] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0111] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0112] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 1100 mesh, and the compressive strength is 1500kg / cm 2 , Shore hardness is 76Hs, specific surface area is 6m 2 / g, elastic modulus is 2.3×10 6 kg / cm 3 .

[0113] The preparation method of the phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 60°C for 11 minutes, adding a formaldehyde solution with a mass concentration of 62% when the temperature reaches 85°C, reacting for 65 minutes, and cooling to obtain the phenolic resin; the weight ratio of the phenol, NaOH, water and formaldehyde is 26:7:70.

[0114] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0115] (1) mixing bauxite, basalt fiber, silicon carbide, silicon dioxide powder and water to obtain a mixture A;

[0116] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0117] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0118] Comparative Example 5

[0119] This comparative example provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight:

[0120] 63 parts of bauxite, 9 parts of basalt fiber, 4 parts of silicon carbide, 12 parts of silicon dioxide powder, 8 parts of modified phenolic resin binder, 24 parts of ethanol, and 18 parts of water;

[0121] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0122] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0123] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 800 mesh, and the compressive strength is 1400kg / cm 2 , Shore hardness is 72Hs, specific surface area is 4.5m 2 / g, elastic modulus is 2.1×10 6 kg / cm 3 .

[0124] The preparation method of the modified phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 60°C for 11 minutes, adding a formaldehyde solution with a mass concentration of 62% when the temperature reaches 85°C, reacting for 65 minutes, adding lignin sulfonate, reacting at 90°C for 2.7 hours, then adding bentonite while maintaining the temperature and continuing to stir for 65 minutes, and then cooling to obtain the modified phenolic resin; the weight ratio of phenol, NaOH, water, formaldehyde, lignin sulfonate and bentonite is 26:7:70:62:11.

[0125] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0126] (1) mixing bauxite, basalt fiber, silicon carbide, silicon dioxide powder and water to obtain a mixture A;

[0127] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0128] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0129] Comparative Example 6

[0130] This comparative example provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight:

[0131] 63 parts of bauxite, 9 parts of basalt fiber, 4 parts of silicon carbide, 12 parts of silicon dioxide powder, 8 parts of modified phenolic resin binder, 24 parts of ethanol, and 18 parts of water;

[0132] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0133] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0134] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 1400 mesh, and the compressive strength is 1600kg / cm 2 , Shore hardness is 80Hs, specific surface area is 8m 2 / g, elastic modulus is 2.5×10 6 kg / cm 3 .

[0135] The preparation method of the modified phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 60°C for 11 minutes, adding a formaldehyde solution with a mass concentration of 62% when the temperature reaches 85°C, reacting for 65 minutes, adding lignin sulfonate, reacting at 90°C for 2.7 hours, then adding bentonite while maintaining the temperature and continuing to stir for 65 minutes, and then cooling to obtain the modified phenolic resin; the weight ratio of phenol, NaOH, water, formaldehyde, lignin sulfonate and bentonite is 26:7:70:62:11.

[0136] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0137] (1) mixing bauxite, basalt fiber, silicon carbide, silicon dioxide powder and water to obtain a mixture A;

[0138] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0139] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0140] Comparative Example 7

[0141] This comparative example provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight:

[0142] 63 parts of bauxite, 9 parts of basalt fiber, 4 parts of silicon carbide, 8 parts of modified phenolic resin binder, 24 parts of ethanol, and 18 parts of water;

[0143] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0144] Among them, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh; the average diameter of basalt fiber is 12 μm, and the average length is 0.75 mm;

[0145] The preparation method of the modified phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 60°C for 11 minutes, adding a formaldehyde solution with a mass concentration of 62% when the temperature reaches 85°C, reacting for 65 minutes, adding lignin sulfonate, reacting at 90°C for 2.7 hours, then adding bentonite while maintaining the temperature and continuing to stir for 65 minutes, and then cooling to obtain the modified phenolic resin; the weight ratio of phenol, NaOH, water, formaldehyde, lignin sulfonate and bentonite is 26:7:70:62:11.

[0146] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0147] (1) mixing bauxite, basalt fiber, silicon carbide and water to obtain a mixture A;

[0148] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0149] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0150] Comparative Example 8

[0151] This comparative example provides a refractory material containing bauxite, which is prepared from the following raw materials in parts by weight:

[0152] 63 parts of bauxite, 4 parts of silicon carbide, 12 parts of silicon dioxide powder, 8 parts of modified phenolic resin binder, 24 parts of ethanol, and 18 parts of water;

[0153] The raw material composition of the bauxite by weight is: Al2O3: 72%, SiO2: 4.5%, TiO2: 2%, Fe2O3: 1.75% and others;

[0154] Wherein, the average particle size of bauxite is 270 mesh; the average particle size of silicon carbide is 75 mesh;

[0155] The raw material composition of the silica powder by weight is: SiO2: 67%, Al2O3: 14%, CaO: 1.5%, MgO: 1% and others; the average particle size of the silica powder is 1100 mesh, and the compressive strength is 1500kg / cm 2 , Shore hardness is 76Hs, specific surface area is 6m 2 / g, elastic modulus is 2.3×10 6 kg / cm 3 .

[0156] The preparation method of the modified phenolic resin comprises: mixing phenol, NaOH and water, heating at a temperature of 60°C for 11 minutes, adding a formaldehyde solution with a mass concentration of 62% when the temperature reaches 85°C, reacting for 65 minutes, adding lignin sulfonate, reacting at 90°C for 2.7 hours, then adding bentonite while maintaining the temperature and continuing to stir for 65 minutes, and then cooling to obtain the modified phenolic resin; the weight ratio of phenol, NaOH, water, formaldehyde, lignin sulfonate and bentonite is 26:7:70:62:11.

[0157] The method for preparing the refractory material containing bauxite in this embodiment comprises the following steps:

[0158] (1) mixing bauxite, silicon carbide, silicon dioxide powder and water to obtain a mixture A;

[0159] (2) mixing the modified phenolic resin binder and ethanol and stirring to obtain a mixture B;

[0160] (3) Mixing the mixture A and the mixture B to obtain the refractory material.

[0161] Test Example: The refractory materials prepared in the above-mentioned Examples 1-4 and Comparative Examples 1-8 were pressurized, shaped, dried, and subjected to the following tests:

[0162] Test fire resistance according to GB / T 14907-2018;

[0163] The refractory material was made into a test piece with a size of 500mm×500mm, and then the surface cracking was observed after 1 hour of refractory fire, and the number of cracks on the surface of the test piece was recorded;

[0164] The refractory material is made into a test piece of 500mm×500mm specification. According to the formula θ=(To-T) / To×100%, θ is the insulation efficiency attenuation, in %; To is the benchmark insulation efficiency, in min; T is the insulation efficiency after 1h of fire, in min.

[0165] The results are shown in Table 1 below:

[0166] Table 1

[0167]

[0168]

[0169] Finally, it should be noted that the above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents. All technical solutions and improvements that do not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A refractory material containing bauxite, characterized in that: It is prepared from the following raw materials in parts by weight: 60-66 parts of bauxite, 8-10 parts of basalt fiber, 3-5 parts of silicon carbide, 10-14 parts of silicon dioxide powder, 6-10 parts of modified phenolic resin binder, 22-26 parts of ethanol, and 16-20 parts of water; The raw material composition of the silicon dioxide powder by weight is: SiO2: 65-69%, Al2O3: 12-16%, CaO: 1-2%, MgO: 0.5-1.5% and others; the particle size of the silicon dioxide powder is 1000-1200 mesh, and the compressive strength is 1000-2000kg / cm 2 , Shore hardness is 72-80Hs, specific surface area is 5.5-6.5m 2 / g, elastic modulus is 2.1-2.5×10 6 kg / cm 3 ; The basalt fiber has a diameter of 10-15 μm and a length of 0.5-1 mm; The preparation method of the modified phenolic resin binder comprises: mixing phenol, NaOH and water, heating at a temperature of 55-65° C. for 10-12 min, adding formaldehyde solution when the temperature rises to 80-90° C., reacting for 60-70 min, adding lignin sulfonate, reacting at 88-92° C. for 2.4-3 h, then adding bentonite while maintaining the temperature and stirring for 60-70 min, and cooling to obtain the modified phenolic resin binder.

2. The refractory material containing bauxite according to claim 1, characterized in that: The raw material composition of the bauxite in parts by weight is: Al2O3: 70-74%, SiO2: 3-6%, TiO2: 1.5-2.5%, Fe2O3: 1.5-2% and others.

3. The refractory material containing bauxite according to claim 1, characterized in that: The particle size of the bauxite is 240-300 meshes; the particle size of the silicon carbide is 50-100 meshes.

4. The refractory material containing bauxite according to claim 1, characterized in that: The weight ratios of the phenol, NaOH, water, formaldehyde, lignin sulfonate and bentonite are (24-28): (5-9): (65-75): (60-64): (10-12).

5. The refractory material containing bauxite according to claim 1, characterized in that: The mass concentration of the formaldehyde solution is 60-64%.

6. A method for preparing a refractory material containing bauxite according to any one of claims 1 to 5, characterized in that the steps include: (1) Bauxite, basalt fiber, silicon carbide, silicon dioxide powder and water are mixed and stirred to obtain a mixture A; (2) mixing the modified phenolic resin binder and ethanol to obtain a mixture B; (3) Mixing mixture A and mixture B is performed to obtain the refractory material.

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