Refractory material taking secondary aluminum ash as raw material and preparation method thereof

Abstract

The invention relates to a refractory material taking secondary aluminum ash as a raw material and a preparation method thereof, and in the preparation method of the refractory material taking the secondary aluminum ash as the raw material, a mixture and water are contained; the mixture is prepared from the following raw materials: treated secondary aluminum ash, attapulgite, limestone, modified mullite fiber, an adhesive and muscovite; the preparation method of the modified mullite fiber comprises the following steps: impregnating mullite fiber in a mixed solution of liquid phenolic resin, silicon powder and isopropanol, and sequentially carrying out drying and heat treatment after impregnation to obtain the modified mullite fiber, a treatment method of the treated secondary aluminum ash comprises the steps that the secondary aluminum ash is crushed, then acid leaching and water washing are conducted in sequence, and finally the treated secondary aluminum ash is obtained through drying. According to the present invention, the resource utilization of the industrial solid waste can be achieved, the production cost of the refractory material can be reduced, and the refractory material has advantages of excellent refractoriness, excellent refractoriness under load, excellent compression strength at normal temperature, excellent reheating linear change and excellent thermal shock resistance, such that the refractory material can be suitable for the high-temperature industrial kiln.

Description

Technical Field

[0001] The present invention relates to the technical field of solid waste resource utilization in the aluminum industry, and in particular to a refractory material using secondary aluminum ash as a raw material and a preparation method thereof. Background Art

[0002] Aluminum is a key component of common refractories, and its high content requires significant aluminum resources during their production. If the resulting secondary aluminum ash is not properly handled and stored for extended periods, it will not only occupy valuable land resources but also cause severe pollution to the atmosphere, soil, and water bodies due to its toxic components, such as nitrides, fluorides, and chlorides, endangering both the ecological environment and human health. Furthermore, the unused large amounts of secondary aluminum ash represent a significant waste of resources. Secondary aluminum ash typically contains over 60% aluminum oxide and approximately 5%-10% magnesium oxide, possessing significant potential for utilization. To address the challenges of aluminum ash disposal and achieve resource recycling, numerous technologies have been developed to prepare refractory materials from aluminum ash. However, the presence of various impurities in secondary aluminum ash, such as Mg, Ca, F, Fe, Cu, Zn, and Si, severely degrades the performance of the resulting refractory materials, resulting in poor performance in key indicators such as strength, refractoriness, and high-temperature cracking resistance. These impurities make it difficult to meet the increasingly stringent requirements of modern high-temperature industries. For example, in some high-temperature kilns, insufficient refractory strength leads to frequent damage to the furnace lining, necessitating frequent repairs and replacements, which not only increases production costs but also reduces efficiency. Insufficient refractoriness limits the operating temperature of the kiln, hindering the implementation of some new processes. Poor high-temperature cracking resistance can cause cracks in the refractory materials during drastic temperature fluctuations, leading to leakage of high-temperature gases within the furnace, posing a safety hazard and accelerating the deterioration of the refractory materials.

[0003] Therefore, in view of the shortcomings of the existing technology, it is necessary to provide a refractory material preparation method using secondary aluminum ash as raw material and a preparation method thereof to solve the shortcomings of the existing technology. Summary of the Invention

[0004] The first object of the present invention is to overcome the shortcomings of the prior art and provide a method for preparing a refractory material using secondary aluminum ash as a raw material. The refractory material obtained by the method uses secondary aluminum ash as a raw material, has high refractoriness and does not crack under high temperature conditions.

[0005] The above-mentioned purpose of the present invention is achieved through the following technical measures: Provided is a method for preparing refractory materials using secondary aluminum ash as raw materials, comprising a mixture and water; the raw materials of the mixture contain treated secondary aluminum ash, attapulgite, limestone, modified mullite fiber, adhesive and muscovite.

[0006] Preferably, the modified mullite fiber is prepared by dipping the mullite fiber in a mixture of liquid phenolic resin, silicon powder and isopropyl alcohol, and then drying and heat treating the mixture in sequence to obtain the modified mullite fiber.

[0007] Preferably, the processing method of the above-mentioned treated secondary aluminum ash is to crush the secondary aluminum ash, then carry out acid leaching and water washing in sequence, and finally dry it to obtain the treated secondary aluminum ash; in the secondary aluminum ash, the weight proportion of aluminum oxide is 70wt% to 80wt%, the weight proportion of magnesium oxide is 5wt% to 7wt%, and the weight proportion of silicon dioxide is less than 8wt%.

[0008] The present invention is a method for preparing a refractory material using secondary aluminum ash as raw material, wherein the mixture comprises, by weight percentage: Secondary aluminum ash after treatment: 65wt%~70wt%; Attapulgite: 5wt% to 8wt%; Limestone: 2wt%~5wt%; Modified mullite fiber: 5wt% to 10wt%; Binder: 3wt% to 5wt%; Muscovite: remainder.

[0009] The present invention is a method for preparing a refractory material using secondary aluminum ash as raw material, wherein the mixture comprises, by weight percentage: Secondary aluminum ash after treatment: 68.5wt%; Attapulgite: 6.5wt%; Limestone: 3.8wt%; Modified mullite fiber: 7.6wt%; Binder: 4.2wt%; Muscovite: remainder.

[0010] The mass ratio of liquid phenolic resin, silicon powder and isopropyl alcohol in the mixed liquid is (10-15): (3-8): (60-80), and the mass ratio of the mullite fiber to the mixed liquid is (3-5): (5-10).

[0011] The mass ratio of the liquid phenolic resin, silicon powder and isopropyl alcohol in the mixed liquid is 12:6.5:72, and the mass ratio of the mullite fiber to the mixed liquid is 4:9.

[0012] Preferably, the preparation method of the modified mullite fiber is carried out by the following steps: A1. Immerse the mullite fiber in a mixture of liquid phenolic resin and silicon powder for 1 to 3 hours, and then remove the immersed mullite fiber; A2, drying the impregnated mullite fiber of A1 at a temperature of 70° C. to 90° C. for 8 h to 12 h to obtain dried mullite fiber; A3. Heat-treating the dried mullite fiber of A2 at a temperature of 750° C. to 900° C. for 4 h to 8 h to obtain modified mullite fiber.

[0013] Preferably, the method for processing the secondary aluminum ash after the above treatment is: B1. Crushing the secondary aluminum ash to above 400 mesh to obtain crushed secondary aluminum ash; B2, mixing the crushed secondary aluminum ash of B1 with hydrochloric acid at a weight ratio of 1: (0.8-1) and a concentration of 5.0wt%, stirring at room temperature for 4h-8h, and then filtering to obtain the acid-leached secondary aluminum ash; B3, using pure water to wash the acid-leached secondary aluminum ash of B2 until the pH value of the washing liquid is 6.5-7.5, and finally drying the solid to obtain the treated secondary aluminum ash.

[0014] Preferably, the preparation method of the modified mullite fiber is carried out by the following steps: A1. Immerse the mullite fiber in a mixture of liquid phenolic resin and silicon powder for 1-3 hours, and then remove the immersed mullite fiber; A2, drying the impregnated mullite fiber of A1 at 82.5° C. for 10 h to obtain dried mullite fiber; A3. The dried mullite fiber of A2 is heat-treated at 856° C. for 6 h to obtain modified mullite fiber.

[0015] Preferably, the method for processing the secondary aluminum ash after the above treatment is: B1. Crush the secondary aluminum ash to above 400 mesh; B2, mixing the crushed secondary aluminum ash of B1 with hydrochloric acid having a weight ratio of 1:0.85 and a concentration of 5.0wt%, stirring at room temperature for 6 hours, and then filtering to obtain the acid-leached secondary aluminum ash; B3, using pure water to wash the acid-leached secondary aluminum ash of B2 until the pH value of the washing liquid is 6.5-7.5, and finally drying the solid to obtain the treated secondary aluminum ash.

[0016] The method for preparing a refractory material using secondary aluminum ash as raw material of the present invention is carried out by the following steps: S1. Stir and mix the raw materials according to the proportions, let them stand, and obtain a mixture; S2. Mix the mixture obtained in S1 with water and press-form the mixture at a pressure of 60 MPa to 65 MPa for a holding time of 30 s to 120 s to obtain a green body, wherein the mass ratio of the mixture to water is 1:0.5 to 0.8; S3. The green body is subjected to high-temperature calcination, with a heating rate of 5°C / min to 10°C / min, a temperature of 1250°C to 1550°C, and a time of 60min to 240min to obtain the refractory material.

[0017] The second object of the present invention is to avoid the shortcomings of the prior art and provide a refractory material using secondary aluminum ash as raw material. The refractory material using secondary aluminum ash as raw material uses secondary aluminum ash as the main raw material and has high refractoriness and does not crack under high temperature conditions.

[0018] The above-mentioned purpose of the present invention is achieved through the following technical measures: Provided is a refractory material using secondary aluminum ash as a raw material, which is prepared by the above-mentioned method for preparing a refractory material using secondary aluminum ash as a raw material.

[0019] The present invention provides a refractory material using secondary aluminum ash as a raw material and a preparation method thereof, wherein the preparation method of the refractory material using secondary aluminum ash as a raw material comprises a mixture and water; the raw materials of the mixture comprise treated secondary aluminum ash, attapulgite, limestone, modified mullite fiber, a binder, and muscovite; the preparation method of the modified mullite fiber comprises impregnating the mullite fiber in a mixture of liquid phenolic resin, silicon powder, and isopropyl alcohol, drying and heat-treating the modified mullite fiber after the impregnation is completed; and the processing method of the treated secondary aluminum ash comprises crushing the secondary aluminum ash, then acid-leaching and washing the secondary aluminum ash in sequence, and finally drying the treated secondary aluminum ash. The raw material refractory material of the present invention uses secondary aluminum ash as a main raw material, can realize resource utilization of industrial solid waste, and can reduce the production cost of the refractory material. Moreover, the refractory material obtained by the present invention has excellent refractoriness, softening temperature under load, room temperature compressive strength, reburning line change, and thermal shock resistance, so the refractory material can be applied to high-temperature industrial kilns. DETAILED DESCRIPTION

[0020] The technical solutions of the present invention are further illustrated with reference to the following examples. Unless otherwise specified, the raw materials used in the following examples are all commercially available products. The adhesive of the present invention is sodium carboxymethyl cellulose (CMC), and the liquid phenolic resin is purchased from Wuxi Mingyang Adhesive Materials Co., Ltd. under the model number 2123. Silicon powder is purchased from Anyang Zhongyu Jinming Silicon Industry Co., Ltd. under the model number 5N. Mullite fiber is purchased from Zibo Yubang Energy Saving Materials Co., Ltd. under the model number SS-PMF1700.

[0021] Example 1 A method for preparing refractory materials using secondary aluminum ash as raw materials comprises a mixture and water; the raw materials of the mixture comprise treated secondary aluminum ash, attapulgite, limestone, modified mullite fiber, adhesive and muscovite.

[0022] In the mixture, by weight percentage: Secondary aluminum ash after treatment: 65wt%~70wt%; Attapulgite: 5wt% to 8wt%; Limestone: 2wt%~5wt%; Modified mullite fiber: 5wt% to 10wt%; Binder: 3wt% to 5wt%; Muscovite: remainder.

[0023] The modified mullite fiber is prepared by impregnating the mullite fiber in a mixture of liquid phenolic resin, silica fume, and isopropyl alcohol, followed by drying and heat treatment to obtain the modified mullite fiber. The mass ratio of the liquid phenolic resin, silica fume, and isopropyl alcohol in the mixture is (10-15):(3-8):(60-80), and the mass ratio of the mullite fiber to the mixture is (3-5):(5-10).

[0024] The preparation method of modified mullite fiber is carried out by the following steps: A1. Immerse the mullite fiber in a mixture of liquid phenolic resin and silicon powder for 1 to 3 hours, and then remove the immersed mullite fiber; A2, drying the impregnated mullite fiber of A1 at a temperature of 70° C. to 90° C. for 8 h to 12 h to obtain dried mullite fiber; A3. Heat-treating the dried mullite fiber of A2 at a temperature of 750° C. to 900° C. for 4 h to 8 h to obtain modified mullite fiber.

[0025] The method for treating the treated secondary aluminum ash is to crush the secondary aluminum ash, then carry out acid leaching and water washing in sequence, and finally dry it to obtain the treated secondary aluminum ash.

[0026] The treatment method of secondary aluminum ash after treatment is: B1. Crushing the secondary aluminum ash to above 400 mesh to obtain crushed secondary aluminum ash; B2, mixing the crushed secondary aluminum ash of B1 with hydrochloric acid at a weight ratio of 1: (0.8-1) and a concentration of 5.0wt%, stirring at room temperature for 4h-8h, and then filtering to obtain the acid-leached secondary aluminum ash; B3, using pure water to wash the acid-leached secondary aluminum ash of B2 until the pH value of the washing liquid is 6.5-7.5, and finally drying the solid to obtain the treated secondary aluminum ash.

[0027] In the secondary aluminum ash of the present invention, the weight proportion of aluminum oxide is 65wt% to 75wt%, the weight proportion of magnesium oxide is 5wt% to 7wt%, and the weight proportion of silicon dioxide is less than 8wt%.

[0028] It should be noted that, since the secondary aluminum ash contains a small amount of elemental metal, alkaline earth metal oxide, non-metallic oxide, and some AlN, the present invention removes low-melting-point, volatile impurities, easily hydrated, and easily gas-generating components by acid leaching and water washing the secondary aluminum ash, thereby reducing the interference of impurity ions, improving sintering performance, and enriching high-refractory phases, eliminating structural hidden dangers such as expansion, cracking, and porosity, and ultimately significantly improving the refractoriness, structural stability, and high-temperature strength of the refractory material, so that it meets the use requirements of industrial high-temperature environments. The role of the modified mullite fiber of the present invention is to form silicon carbide by adding a carbon source and a silicon source, thereby doping silicon carbide in the mullite fiber, so that a network skeleton is formed between the refractory material and other materials. When the refractory material produces microcracks due to thermal stress, the modified mullite fiber can consume energy through bridging, pull-out, and other effects to prevent crack propagation. In addition, the modified mullite fiber can also improve the tensile strength and fracture toughness of the fiber itself, making it less prone to brittleness at high temperatures, and reduce the overall thermal expansion difference of the material, reducing structural damage caused by thermal shock.

[0029] The method for preparing a refractory material using secondary aluminum ash as raw material of the present invention is carried out by the following steps: S1, stirring and mixing the raw materials of the mixture according to the proportion, and letting it stand to obtain a mixture; S2. Mix the mixture obtained in S1 with water and press-form the mixture at a pressure of 60 MPa to 65 MPa for a holding time of 30 s to 120 s to obtain a green body. The mass ratio of the mixture to water is 1:0.5 to 0.8. S3. The green body is subjected to high-temperature calcination. The heating rate of the high-temperature calcination is 5°C / min to 10°C / min, the temperature is 1250°C to 1550°C, and the time is 60min to 240min to obtain a refractory material.

[0030] The refractory material of the present invention uses secondary aluminum ash as raw material. The refractory material uses secondary aluminum ash as the main raw material, which can not only realize the resource utilization of industrial solid waste, but also reduce the production cost of refractory materials. Moreover, the refractory material obtained by the present invention has excellent refractoriness, softening temperature under load, room temperature compressive strength, reburning line change and thermal shock resistance, so the refractory material can be used in high-temperature industrial kilns.

[0031] Example 2 A method for preparing a refractory material using secondary aluminum ash as raw material, the other features of which are the same as those of Example 1, except that: In the mixture, by weight percentage: Secondary aluminum ash after treatment: 65wt%; Attapulgite: 8wt%; Limestone: 5wt%; Modified mullite fiber: 10wt%; Binder: 3wt%; Muscovite: remainder.

[0032] The modified mullite fiber is prepared by impregnating the mullite fiber in a mixture of liquid phenolic resin, silica fume, and isopropyl alcohol. Following impregnation, the fiber is dried and then heat-treated to obtain the modified mullite fiber. The mass ratio of the liquid phenolic resin, silica fume, and isopropyl alcohol in the mixture is 15:3:80, and the mass ratio of the mullite fiber to the mixture is 3:5.

[0033] The preparation method of modified mullite fiber is carried out by the following steps: A1. Immerse the mullite fiber in a mixture of liquid phenolic resin and silicon powder for 1 hour, and then remove the immersed mullite fiber; A2, drying the impregnated mullite fiber of A1 at 70° C. for 8 h to obtain dried mullite fiber; A3. The dried mullite fiber of A2 is heat-treated at 750° C. for 8 h to obtain modified mullite fiber.

[0034] The method for treating the treated secondary aluminum ash is to crush the secondary aluminum ash, then carry out acid leaching and water washing in sequence, and finally dry it to obtain the treated secondary aluminum ash.

[0035] The treatment method of secondary aluminum ash after treatment is: B1. Crushing the secondary aluminum ash to above 400 mesh to obtain crushed secondary aluminum ash; B2, mixing the crushed secondary aluminum ash of B1 with hydrochloric acid having a weight ratio of 1:0.8 and a concentration of 5.0 wt%, stirring at room temperature for 4 h, and then filtering to obtain the acid-leached secondary aluminum ash; B3, using pure water to wash the acid-leached secondary aluminum ash of B2 until the pH value of the washing liquid is 6.5, and finally drying the solid to obtain the treated secondary aluminum ash.

[0036] The elemental composition of the secondary aluminum ash from a recycled aluminum plant used in this embodiment is shown in Table 1: Table 1: Composition of secondary aluminum ash in this embodiment

[0037] The method for preparing a refractory material using secondary aluminum ash as raw material of the present invention is carried out by the following steps: S1, stirring and mixing the raw materials of the mixture according to the proportion, and letting it stand to obtain a mixture; S2. Mix the mixture obtained in S1 with water and press-form the mixture at a pressure of 60 MPa and a holding time of 120 s to obtain a green body. The mass ratio of the mixture to water is 1:0.8. S3. The green body is subjected to high-temperature calcination with a heating rate of 10°C / min, a temperature of 1550°C, and a calcination time of 240 min to obtain a refractory material.

[0038] Example 3 A method for preparing a refractory material using secondary aluminum ash as raw material, the other features of which are the same as those of Example 1, except that: In the mixture, by weight percentage: Secondary aluminum ash after treatment: 70wt%; Attapulgite: 5wt%; Limestone: 2wt%; Modified mullite fiber: 5wt%; Binder: 5wt%; Muscovite: remainder.

[0039] The modified mullite fiber is prepared by impregnating the mullite fiber in a mixture of liquid phenolic resin, silica fume, and isopropyl alcohol. After impregnation, the fiber is dried and then heat-treated to obtain the modified mullite fiber. The mass ratio of the liquid phenolic resin, silica fume, and isopropyl alcohol in the mixture is 10:8:60, and the mass ratio of the mullite fiber to the mixture is 5:10.

[0040] The preparation method of modified mullite fiber is carried out by the following steps: A1. Immerse the mullite fiber in a mixture of liquid phenolic resin and silicon powder for 1 hour, and then remove the immersed mullite fiber; A2, drying the impregnated mullite fiber of A1 at 90° C. for 12 h to obtain dried mullite fiber; A3. The dried mullite fiber of A2 is heat-treated at 900° C. for 4 h to obtain modified mullite fiber.

[0041] The method for treating the treated secondary aluminum ash is to crush the secondary aluminum ash, then carry out acid leaching and water washing in sequence, and finally dry it to obtain the treated secondary aluminum ash.

[0042] The treatment method of secondary aluminum ash after treatment is: B1. Crushing the secondary aluminum ash to above 400 mesh to obtain crushed secondary aluminum ash; B2, mixing the crushed secondary aluminum ash in B1 with hydrochloric acid having a weight ratio of 1:1 and a concentration of 5.0 wt%, stirring at room temperature for 8 h, and then filtering to obtain the acid-leached secondary aluminum ash; B3, washing the acid-leached secondary aluminum ash of B2 with pure water until the pH value of the washing liquid is 7.5, and finally drying the solid to obtain the treated secondary aluminum ash.

[0043] The composition of the secondary aluminum ash from a recycled aluminum plant used in this embodiment is shown in Table 2: Table 2: Composition of secondary aluminum ash in this embodiment

[0044] The method for preparing a refractory material using secondary aluminum ash as raw material of the present invention is carried out by the following steps: S1, stirring and mixing the raw materials of the mixture according to the proportion, and letting it stand to obtain a mixture; S2. Mix the mixture obtained in S1 with water and press-form the mixture at a pressure of 65 MPa and a holding time of 30 seconds to obtain a green body. The mass ratio of the mixture to water is 1:0.8. S3. The green body is subjected to high-temperature calcination with a heating rate of 5°C / min, a temperature of 1250°C, and a calcination time of 60 min to obtain a refractory material.

[0045] Example 4 A method for preparing a refractory material using secondary aluminum ash as raw material, the other features of which are the same as those of Example 1, except that: in the mixture, by weight percentage: Secondary aluminum ash after treatment: 68.5wt%; Attapulgite: 6.5wt%; Limestone: 3.8wt%; Modified mullite fiber: 7.6wt%; Binder: 4.2wt%; Muscovite: remainder.

[0046] The modified mullite fiber is prepared by impregnating the mullite fiber in a mixture of liquid phenolic resin, silica fume, and isopropyl alcohol. After impregnation, the fiber is dried and then heat-treated to obtain the modified mullite fiber. The mass ratio of the liquid phenolic resin, silica fume, and isopropyl alcohol in the mixture is 12:6.5:72, and the mass ratio of the mullite fiber to the mixture is 4:9.

[0047] The preparation method of modified mullite fiber is carried out by the following steps: A1. Immerse the mullite fiber in a mixture of liquid phenolic resin and silicon powder for 1-3 hours, and then remove the immersed mullite fiber; A2, drying the impregnated mullite fiber of A1 at 82.5° C. for 10 h to obtain dried mullite fiber; A3. The dried mullite fiber of A2 is heat-treated at 856° C. for 6 h to obtain modified mullite fiber.

[0048] The method for treating the treated secondary aluminum ash is to crush the secondary aluminum ash, then carry out acid leaching and water washing in sequence, and finally dry it to obtain the treated secondary aluminum ash.

[0049] The treatment method of secondary aluminum ash after treatment is: B1. Crush the secondary aluminum ash to above 400 mesh; B2, mixing the crushed secondary aluminum ash of B1 with hydrochloric acid having a weight ratio of 1:0.85 and a concentration of 5.0wt%, stirring at room temperature for 6 hours, and then filtering to obtain the acid-leached secondary aluminum ash; B3, washing the acid-leached secondary aluminum ash of B2 with pure water until the pH value of the washing solution is 7.0, and finally drying the solid to obtain the treated secondary aluminum ash.

[0050] The elemental composition of the secondary aluminum ash from a recycled aluminum plant used in this embodiment is shown in Table 3: Table 3: Composition of secondary aluminum ash in this embodiment

[0051] The method for preparing a refractory material using secondary aluminum ash as raw material of the present invention is carried out by the following steps: S1, stirring and mixing the raw materials of the mixture according to the proportion, and letting it stand to obtain a mixture; S2. Mix the mixture obtained in S1 with water and press-form the mixture at a pressure of 63 MPa and a holding time of 60 s to obtain a green body. The mass ratio of the mixture to water is 1:0.6. S3. The green body is subjected to high-temperature calcination with a heating rate of 8°C / min, a temperature of 1400°C, and a calcination time of 150 min to obtain a refractory material.

[0052] Comparative Example 1 A method for preparing a refractory material using secondary aluminum ash as raw material, the other features of which are the same as those of Example 4, except that: in the mixture, by weight percentage: Secondary aluminum ash after treatment: 50.0wt%; Attapulgite: 10.0wt%; Limestone: 8.0wt%; Modified mullite fiber: 3.0wt%; Binder: 4.2wt%; Muscovite: remainder.

[0053] Comparative Example 2 A method for preparing a refractory material using secondary aluminum ash as raw material, the other features of which are the same as those of Example 4, except that: in the mixture, by weight percentage: Secondary aluminum ash after treatment: 75.0wt%; Attapulgite: 4.0wt%; Limestone: 1.0wt%; Modified mullite fiber: 13.0wt%; Binder: 4.2wt%; Muscovite: remainder.

[0054] Comparative Example 3 A method for preparing a refractory material using secondary aluminum ash as raw material, with other features identical to those of Example 4, except that the modified mullite fiber is prepared by immersing the mullite fiber in a mixture of liquid phenolic resin, silica fume, and isopropyl alcohol, followed by drying and heat treatment to obtain the modified mullite fiber. The mass ratio of the liquid phenolic resin, silica fume, and isopropyl alcohol in the mixture is 5:10:72, and the mass ratio of the mullite fiber to the mixture is 4:9.

[0055] Comparative Example 4 A method for preparing a refractory material using secondary aluminum ash as raw material, with other features identical to those of Example 4, except that the modified mullite fiber is prepared by immersing the mullite fiber in a mixture of liquid phenolic resin, silica fume, and isopropyl alcohol, followed by drying and heat treatment to obtain the modified mullite fiber. The mass ratio of the liquid phenolic resin, silica fume, and isopropyl alcohol in the mixture is 12:6.5:72, and the mass ratio of the mullite fiber to the mixture is 8:3.

[0056] Comparative Example 5 A method for preparing a refractory material using secondary aluminum ash as raw material, the other features of which are the same as those of Example 4, except that: in this embodiment, the modified mullite fiber in the mixture is replaced by mullite fiber.

[0057] Comparative Example 6 A method for preparing a refractory material using secondary aluminum ash as raw material, the other features of which are the same as those of Example 4, except that: in this embodiment, the treated secondary aluminum ash in the mixture is replaced by untreated secondary aluminum ash.

[0058] Comparative Example 7 A method for preparing a refractory material using secondary aluminum ash as raw material, the other features of which are the same as those of Example 4, except that: in the mixture, by weight percentage: Secondary aluminum ash after treatment: 68.5wt%; Attapulgite: 14.1wt%; Limestone: 3.8wt%; Binder: 4.2wt%; Muscovite: remainder.

[0059] Comparative Example 8 A method for preparing a refractory material using secondary aluminum ash as raw material, the other features of which are the same as those of Example 4, except that: in the mixture, by weight percentage: Secondary aluminum ash after treatment: 68.5wt%; Modified mullite fiber: 14.1wt%; Limestone: 3.8wt%; Binder: 4.2wt%; Muscovite: remainder.

[0060] Effect Examples The refractory materials of Examples 2 to 4 and the refractory materials of Comparative Examples 1 to 8 were subjected to various performance tests to obtain performance data as shown in Table 4, wherein the test method is as follows: (1) Refractoriness: Tested in accordance with GB7322-87 Refractories Refractoriness Test; (2) Load softening temperature: measured in accordance with the "YB370-75 load softening temperature test method"; (3) Normal temperature compressive strength: Tested in accordance with GB / T5072-2008 Test method for normal temperature compressive strength of refractory materials; (4) Reburning line change: Test in accordance with GB5988-86 Test method for reburning line change of dense shaped refractory products; (5) Thermal shock resistance: Tested in accordance with GB / T 30873-2014 Test method for thermal shock resistance of refractory materials.

[0061] Table 4. Performance data of refractory materials

[0062] In summary, the present invention utilizes a unique filler ratio, combining treated secondary aluminum ash, attapulgite, limestone, modified mullite fiber, a binder, and muscovite, resulting in a refractory material with excellent refractoriness. The material can withstand temperatures exceeding 1784°C and maintain a softening temperature above 1562°C. Furthermore, the refractory material of the present invention exhibits higher compressive and flexural strengths than the comparative example, exhibiting excellent mechanical properties, thereby extending its service life and effectively preventing cracking.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for preparing refractory materials using secondary aluminum ash as raw material, characterized by: Contains mix and water; The raw materials of the mixture include treated secondary aluminum ash, attapulgite, limestone, modified mullite fiber, adhesive and muscovite; The modified mullite fiber is prepared by dipping the mullite fiber in a mixture of liquid phenolic resin, silicon powder and isopropyl alcohol, and then drying and heat treating the mixture in sequence to obtain the modified mullite fiber. The method for treating the treated secondary aluminum ash is to crush the secondary aluminum ash, then sequentially perform acid leaching and water washing, and finally dry the treated secondary aluminum ash to obtain the treated secondary aluminum ash.

2. The method for preparing refractory materials using secondary aluminum ash as raw material according to claim 1, characterized in that: In the mixture, by weight percentage: Secondary aluminum ash after treatment: 65wt%~70wt%; Attapulgite: 5wt% to 8wt%; Limestone: 2wt%~5wt%; Modified mullite fiber: 5wt% to 10wt%; Binder: 3wt% to 5wt%; Muscovite: remainder.

3. The method for preparing refractory materials using secondary aluminum ash as raw material according to claim 2, characterized in that: In the mixture, by weight percentage: Secondary aluminum ash after treatment: 68.5wt%; Attapulgite: 6.5wt%; Limestone: 3.8wt%; Modified mullite fiber: 7.6wt%; Binder: 4.2wt%; Muscovite: remainder.

4. The method for preparing refractory materials using secondary aluminum ash as raw material according to any one of claims 1 to 3, characterized in that: The mass ratio of liquid phenolic resin, silicon powder and isopropyl alcohol in the mixed liquid is (10-15): (3-8): (60-80), and the mass ratio of the mullite fiber to the mixed liquid is (3-5): (5-10).

5. The method for preparing refractory materials using secondary aluminum ash as raw material according to claim 4, characterized in that: The mass ratio of the liquid phenolic resin, silicon powder and isopropyl alcohol in the mixed liquid is 12:6.5:72, and the mass ratio of the mullite fiber to the mixed liquid is 4:

9.

6. The method for preparing refractory materials using secondary aluminum ash as raw material according to any one of claims 1 to 3, characterized in that: The preparation method of the modified mullite fiber is carried out by the following steps: A1. Immerse the mullite fiber in a mixture of liquid phenolic resin and silicon powder for 1 to 3 hours, and then remove the immersed mullite fiber; A2, drying the impregnated mullite fiber of A1 at a temperature of 70° C. to 90° C. for 8 h to 12 h to obtain dried mullite fiber; A3. Heat-treating the dried mullite fiber of A2 at a temperature of 750° C. to 900° C. for 4 h to 8 h to obtain modified mullite fiber.

7. The method for preparing refractory materials using secondary aluminum ash as raw material according to claim 6, characterized in that: The processing method of the secondary aluminum ash after the treatment is: B1. Crushing the secondary aluminum ash to above 400 mesh to obtain crushed secondary aluminum ash; B2, mixing the crushed secondary aluminum ash of B1 with hydrochloric acid at a weight ratio of 1: (0.8-1) and a concentration of 5.0wt%, stirring at room temperature for 4h-8h, and then filtering to obtain the acid-leached secondary aluminum ash; B3, using pure water to wash the acid-leached secondary aluminum ash of B2 until the pH value of the washing liquid is 6.5-7.5, and finally drying the solid to obtain the treated secondary aluminum ash.

8. The method for preparing refractory materials using secondary aluminum ash as raw material according to claim 7, characterized in that: The preparation method of the modified mullite fiber is carried out by the following steps: A1. Immerse the mullite fiber in a mixture of liquid phenolic resin and silicon powder for 1-3 hours, and then remove the immersed mullite fiber; A2, drying the impregnated mullite fiber of A1 at 82.5° C. for 10 h to obtain dried mullite fiber; A3, heat treating the dried mullite fiber of A2 at 856°C for 6 hours to obtain modified mullite fiber; The processing method of the secondary aluminum ash after the treatment is: B1. Crush the secondary aluminum ash to above 400 mesh; B2, mixing the crushed secondary aluminum ash of B1 with hydrochloric acid having a weight ratio of 1:0.85 and a concentration of 5.0wt%, stirring at room temperature for 6 hours, and then filtering to obtain the acid-leached secondary aluminum ash; B3, using pure water to wash the acid-leached secondary aluminum ash of B2 until the pH value of the washing liquid is 6.5-7.5, and finally drying the solid to obtain the treated secondary aluminum ash.

9. The method for preparing refractory materials using secondary aluminum ash as raw material according to any one of claims 1 to 3, characterized in that: Proceed as follows: S1, stirring and mixing the raw materials of the mixture according to the proportion, and letting it stand to obtain the mixture; S2. Mix the mixture obtained in S1 with water and press-form the mixture at a pressure of 60 MPa to 65 MPa for a holding time of 30 s to 120 s to obtain a green body, wherein the mass ratio of the mixture to water is 1:0.5 to 0.8; S3. The green body is subjected to high-temperature calcination, with a heating rate of 5°C / min to 10°C / min, a temperature of 1250°C to 1550°C, and a time of 60min to 240min to obtain the refractory material.

10. A refractory material using secondary aluminum ash as raw material, characterized in that: The refractory material is prepared by the refractory material preparation method using secondary aluminum ash as raw material as described in any one of claims 1 to 9.

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