Red mud resource reutilization method

Abstract

The invention provides a red mud resource reutilization method which comprises the following steps: weighing raw materials according to the proportion of the raw materials, and grinding the raw materials into powder to obtain mixed powder; the raw materials comprise 70%-95% of matrix ceramic, 0.1%-30% of auxiliary ceramic and 0.1%-30% of red mud. Putting the mixed powder into a planetary ball mill, taking out after wet milling, and drying in a vacuum drying oven; crushing the dried powder by using a crusher, and screening by using a screen; the sieved powder is loaded into a graphite mold to be pre-pressed; and sintering the graphite mold filled with the green body in a discharge plasma sintering furnace. And cooling along with the furnace to obtain the red mud doped alumina-based composite ceramic material. According to the method for recycling the red mud, efficient utilization of the red mud is achieved, the red mud is combined with aluminum oxide and auxiliary ceramic, the red mud-doped aluminum oxide-based composite ceramic material is prepared through the processes of high-energy ball milling, spark plasma sintering and the like, and the prepared material has the advantages of being high in toughness, hardness and strength and the like.

Description

Technical Field

[0001] The present invention relates to the field of solid waste resource utilization, and particularly to a method for resource recycling of red mud. Background Art

[0002] Red mud is a harmful solid waste generated in the alumina production process. Its composition is complex, and it shows a red appearance due to the rich iron oxide, so it is called red mud. At present, the Bayer process is the main process for producing alumina. For every 1 ton of alumina produced, 1 - 2 tons of red mud will be produced as a by - product. In the Bayer process, strong alkali is mainly used to leach the aluminum element in bauxite, so the waste residue also has strong alkalinity. The pollution problem of red mud has always been a global issue, and there is still no effective method to solve it. It is urgent to solve the pollution problem of red mud. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for resource recycling of red mud, which realizes the efficient utilization of red mud. By combining with alumina and auxiliary ceramics, and adopting processes such as high - energy ball milling and spark plasma sintering, a red mud - doped alumina - based composite ceramic material is prepared. The prepared material has the advantages of high toughness, high hardness, and high strength.

[0004] To achieve the above - mentioned purpose, the present invention provides a method for resource recycling of red mud, which includes the following steps:

[0005] Weigh the raw materials according to the raw material ratio, and grind the raw materials into powder to obtain a mixed powder; the raw material ratio is 70% - 95% of matrix ceramic, 0.1% - 30% of auxiliary ceramic, and 0.1% - 30% of red mud.

[0006] Place the mixed powder in a planetary ball mill, take it out after wet - milling, and place it in a vacuum drying oven for drying.

[0007] Crush the dried powder with a crusher and pass it through a sieve.

[0008] Load the sieved powder into a graphite mold for pre - pressing.

[0009] Place the graphite mold containing the green body in a spark plasma sintering furnace for sintering. The furnace temperature is raised from room temperature to the target temperature, and the pressure value reaches the target pressure when the furnace temperature reaches the target temperature. After cooling with the furnace, a red mud - doped alumina - based composite ceramic material is obtained.

[0010] Preferably, the matrix ceramic is alumina;

[0011] The auxiliary ceramic includes at least one of zirconia, titanium carbide, and chromium oxide.

[0012] Preferably, the average particle size of the matrix ceramic is 100 - 300 nm; the average particle size of zirconia is 100 - 200 nm; the average particle size of titanium carbide is 30 - 60 μm; the average particle size of chromium oxide is 700 - 900 nm.

[0013] Preferably, the mass ratio of balls to materials in the ball mill is 8 - 10:1, the rotation speed is 200 - 320 r / min, the wet grinding medium is anhydrous ethanol, and the ball milling time is 10 - 24 h.

[0014] Preferably, the drying oven is a vacuum drying oven, the drying temperature is set at 70 - 85 °C, and the drying time is set at 24 h.

[0015] Preferably, the pre-pressing pressure during pre-pressing is 15 - 25 MPa, and the pressure holding time is 5 - 10 min.

[0016] Preferably, the heating rate is 70 - 80 °C / min, the target pressure is 30 - 50 MPa, the sintering time is 10 - 20 min, and the target temperature is 1050 °C - 1250 °C.

[0017] A composite ceramic prepared by a method for the resource utilization of red mud.

[0018] Therefore, the present invention adopts the above-mentioned method for the resource utilization of red mud, and the technical effects are as follows:

[0019] 1. In this paper, alumina, auxiliary ceramics, and red mud are used as raw materials, and a red mud-doped alumina-based composite ceramic material is prepared by planetary ball milling, drying, pulverizing, sieving, pre-pressing, spark plasma sintering, and demolding. The red mud-doped alumina-based composite ceramic material prepared by the present invention has the advantages of high toughness, high hardness, high strength, and low sintering temperature.

[0020] 2. Compared with traditional alumina ceramics, the present invention has higher strength and toughness. It has a lower sintering temperature than alumina ceramics. Using red mud as a doping phase provides an effective method for disposing of red mud, and the preparation process is energy-saving and pollution-free.

[0021] 3. The mechanical properties of the red mud-doped alumina-based composite ceramic material prepared by the present invention are greatly improved. The maximum hardness is 2068.26 HV; the maximum flexural strength is 413.96 MPa; the maximum fracture toughness is 6.50 MPa·m 0.5 . Specific embodiments

[0022] The technical solutions of the present invention will be further described below through examples.

[0023] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the field to which the present invention belongs.

[0024] When preparing red mud-alumina composites by spark plasma sintering (SPS), the reaction mechanism for enhancing the flexural strength mainly relies on the synergistic effect between red mud and alumina, the rapid densification effect of SPS, and the formation of uniformly distributed reinforcement phases. The active SiO2, Fe2O3, and alkaline components (such as Na2O, CaO) in red mud are activated under high temperature and pulsed current, and undergo solid-phase reactions with alumina to form high-modulus mullite (3Al2O3·2SiO2) and calcium hexaaluminate (CaAl 12 O9). These needle-like or granular reinforcement phases are uniformly distributed in the matrix, and significantly improve the flexural strength of the material through crack deflection, bridging effect, and load transfer mechanisms. At the same time, Fe2O3 in red mud is partially reduced to Fe3O4 nanoparticles (magnetite) during the SPS process. This plastic phase further toughens the composite material through pinning effect and energy absorption. In addition, the calcium aluminosilicate glass phases (such as gehlenite, andradite) formed by CaO in red mud with Al2O3 and SiO2 fill the particle gaps, optimize the interfacial bonding, and relieve stress concentration. The rapid sintering of SPS inhibits grain growth, forms a fine-grained structure, and promotes ion diffusion through the electric field, reducing the reaction activation energy, ensuring the uniform distribution and high density of the reinforcement phases. Finally, the synergistic effect of these reinforcement phases (mullite, calcium hexaaluminate, oxide nanoparticles, and glass phase) endows the composite material with excellent flexural properties while maintaining high hardness. And the doping of red mud reduces the sintering temperature of the ceramic.

[0025] Example 1

[0026] A method for the resource recycling of red mud, comprising the following steps:

[0027] (1) Using red mud and alumina as raw materials, mixing them according to the mass ratio of red mud:alumina = x:(1 - x), where x = (0.05, 0.10, 0.15, 0.20, 0.25).

[0028] (2) Placing the mixed powder in a planetary ball mill, using anhydrous ethanol as the grinding medium according to a ball-to-material ratio of 10:1, and ball-milling for 24 h at a rotation speed of 200 r / min;

[0029] (3) Placing the slurry obtained by ball-milling in a vacuum drying oven and drying at 75 °C for 24 h, crushing it with a crusher and passing it through a 200-mesh sieve to obtain dry powder.

[0030] (4) Placing the dried powder in a graphite mold and pre-pressing it with a tablet press at a pressure of 15 MPa for 5 min.

[0031] (5) Place the graphite mold containing the green body in a spark plasma sintering furnace for sintering. The heating rate is 70 °C / min, the sintering temperature is 1100 °C, and the sintering pressure is 40 MPa. The pressure value reaches the target pressure when the furnace temperature reaches the target temperature. After cooling with the furnace, the red mud-doped alumina-based composite ceramic material is obtained.

[0032] When preparing the red mud-alumina composite material by spark plasma sintering (SPS), its reaction mechanism mainly depends on the synergistic effect of red mud and alumina, the rapid densification effect of SPS, and the formation of uniformly distributed reinforcing phases. The active SiO2, Fe2O3, and alkaline components (such as Na2O, CaO) in red mud are activated under the action of high temperature and pulsed current, and undergo solid-phase reactions with alumina to form high-modulus mullite (3Al2O3·2SiO2) and calcium hexaaluminate (CaAl 12 O 19 ), and these needle-like or granular reinforcing phases are uniformly distributed in the matrix, significantly improving the flexural strength of the material through crack deflection, bridging effect, and load transfer mechanisms. At the same time, Fe2O3 in red mud is partially reduced to Fe3O4 nanoparticles (magnetite) during the SPS process, and this plastic phase further toughens the composite material through pinning effect and energy absorption. In addition, the calcium aluminosilicate glass phase (such as calcium aluminosilicate, calcium iron garnet, etc.) formed by CaO in red mud with Al2O3 and SiO2 fills the particle gaps, optimizes the interface bonding, and relieves stress concentration. The rapid sintering of SPS inhibits grain growth, forms a fine-grained structure, promotes ion diffusion through the electric field, reduces the reaction activation energy, and ensures the uniform distribution and high density of the reinforcing phase. Finally, the synergistic effect of these reinforcing phases (mullite, calcium hexaaluminate, oxide nanoparticles, and glass phase) endows the composite material with excellent flexural properties while maintaining high hardness. And the doping of red mud reduces the sintering temperature of the ceramic.

[0033] As shown in Table 1, when x = 0.10, the red mud-alumina composite material prepared in this example has relatively excellent comprehensive properties, among which: the density is 95.53%; the Vickers hardness is 2107.33 HV; the flexural strength is 605.32 MPa; the fracture toughness is 11.29 MPa·m0.5.

[0034] Table 1 When x = 0.10, the red mud-alumina composite material prepared in this example has relatively excellent comprehensive properties

[0035]

[0036] Example 2

[0037] A preparation method of a red mud-doped alumina-based composite ceramic material, comprising the following steps:

[0038] (1) Red mud, alumina and zirconium oxide are used as raw materials, and the ingredients are mixed according to the mass ratio of red mud: alumina: zirconium oxide = 0.1 (1.0-x): 0.9 (1.0-x): x, where x = (0.05, 0.10, 0.15, 0.20, 0.25).

[0039] (2) The mixed powder was placed in a planetary ball mill with a ball-to-material ratio of 10:1 and anhydrous ethanol as the grinding medium, and the mixture was ball milled at a speed of 200 r / min for 24 h;

[0040] (3) The slurry obtained by ball milling was placed in a vacuum drying oven at 75°C and dried for 24 hours, crushed with a pulverizer and passed through a 200-mesh sieve to obtain a dry powder.

[0041] (4) The dried powder was placed in a graphite mold and pre-compressed using a tablet press at a pressure of 15 MPa for 5 min.

[0042] (5) The graphite mold containing the green body is placed in a spark plasma sintering furnace for sintering at a heating rate of 70°C / min and a sintering temperature of 1100°C. The sintering pressure is 40 MPa, and the pressure value reaches the target pressure when the furnace temperature reaches the target temperature. After cooling in the furnace, a red mud-doped alumina-based composite ceramic material is obtained.

[0043] When red mud-alumina composites are prepared by spark plasma sintering (SPS), the reaction mechanism of enhancing the flexural strength mainly depends on the synergistic effect of red mud and alumina, the rapid densification effect of SPS, and the formation of uniformly distributed reinforcement phases. The active SiO2, Fe2O3 and alkaline components (such as Na2O and CaO) in red mud are activated under high temperature and pulse current, and react with alumina in the solid phase to generate high modulus mullite (3Al2O3·2SiO2) and calcium hexaaluminate (CaAl 12O9), these acicular or granular reinforcing phases are uniformly distributed in the matrix, and significantly improve the flexural strength of the material through crack deflection, bridging effect and load transfer mechanism. At the same time, Fe2O3 in the red mud is partially reduced to Fe3O4 nanoparticles (magnetite) during the SPS process. This plastic phase further toughens the composite material through pinning effect and energy absorption. In addition, the calcium aluminosilicate glass phase (such as gehlenite, andradite, etc.) formed by CaO, Al2O3 and SiO2 in the red mud fills the particle gaps, optimizes the interfacial bonding and relieves stress concentration. The rapid sintering of SPS inhibits grain growth, forms a fine-grained structure, promotes ion diffusion through the electric field, reduces the reaction activation energy, and ensures the uniform distribution and high density of the reinforcing phases. Finally, the synergistic effect of these reinforcing phases (mullite, calcium hexaaluminate, oxide nanoparticles and glass phase) endows the composite material with excellent flexural properties while maintaining high hardness. And the doping of red mud reduces the sintering temperature of the ceramic. The improvement of the properties of zirconia (ZrO2) on alumina (Al2O3) ceramics is mainly achieved through the synergistic action of multiple mechanisms such as transformation toughening, fine grain strengthening, solid solution strengthening and residual stress regulation. During the sintering and cooling process, zirconia undergoes a martensitic transformation (tetragonal phase t-ZrO2 changes to monoclinic phase m-ZrO2), accompanied by a volume expansion of 3% - 5%, forming microcracks and local compressive stress fields in the matrix. When the main crack propagates to the vicinity of t-ZrO2 particles, the transformation consumes energy and generates a compressive stress field, effectively hindering crack propagation. At the same time, the microcracks induced by the transformation significantly improve the fracture toughness (KIC can be increased by more than 50%) by dispersing the energy of the main crack. Nano-ZrO2 particles are distributed at the Al2O3 grain boundaries, inhibit the growth of Al2O3 grains through the pinning effect, refine the matrix grains to the micron scale, and improve the strength and hardness of the material using the Hall-Petch effect. At the same time, the addition of ZrO2 reduces the sintering temperature of Al2O3 and promotes densification. At high temperature, Zr 4+ is partially dissolved in the Al2O3 lattice, causing lattice distortion and enhancing the resistance to dislocation movement. The eutectic liquid phase that may form between ZrO2 and Al2O3 at high temperature forms a strongly bonded grain boundary phase after cooling, further optimizing the interfacial bonding strength. The difference in thermal expansion coefficients between ZrO2 and Al2O3 forms a moderate compressive stress during cooling, delaying the initiation of surface cracks.

[0044] As shown in Table 2, when x = 0.15, the red mud-alumina composite material prepared in this example has relatively excellent comprehensive properties, among which: the density is 95.27%; the Vickers hardness is 1659.93 HV; the flexural strength is 583.21 MPa; the fracture toughness is 14.73 MPa·m0.5.

[0045] Table 2 When x = 0.15, the red mud-alumina composite material prepared in this example has relatively excellent comprehensive properties

[0046]

[0047]

[0048] Example 3

[0049] A preparation method of a red mud-doped alumina-based composite ceramic material, comprising the following steps:

[0050] (1) Using red mud, alumina, and chromium oxide powders as raw materials, proportioning according to the mass ratio of red mud:alumina:chromium oxide = 0.1(1.0 - x):0.9(1.0 - x):x, where x = (0.01, 0.015, 0.02, 0.025, 0.03) for mixing.

[0051] (2) Placing the mixed powder in a planetary ball mill, with a ball-to-material ratio of 10:1, using anhydrous ethanol as the grinding medium, and ball milling for 24 h at a rotation speed of 200 r / min;

[0052] (3) Placing the slurry obtained by ball milling in a vacuum drying oven and drying at 75 °C for 24 h, crushing with a pulverizer and passing through a 200-mesh sieve to obtain dry powder.

[0053] (4) Placing the dried powder in a graphite mold and performing pre-pressing with a tablet press at a pressure of 15 MPa and maintaining for 5 min.

[0054] (5) Placing the graphite mold containing the green body in a spark plasma sintering furnace for sintering, with a heating rate of 70 °C / min and a sintering temperature of 1100 °C. The sintering pressure is 40 MPa, and the pressure value reaches the target pressure when the furnace temperature reaches the target temperature. After cooling with the furnace, a red mud-doped alumina-based composite ceramic material is obtained.

[0055] When preparing red mud-alumina composites by spark plasma sintering (SPS), the reaction mechanism for enhancing the flexural strength mainly depends on the synergistic effect of red mud and alumina, the rapid densification effect of SPS, and the formation of uniformly distributed reinforcing phases. The active SiO2, Fe2O3, and alkaline components (such as Na2O, CaO) in red mud are activated under high temperature and pulsed current, and undergo solid-phase reactions with alumina to form high-modulus mullite (3Al2O3·2SiO2) and calcium hexaaluminate (CaAl 12O9), these acicular or granular reinforcing phases are uniformly distributed in the matrix, and significantly improve the flexural strength of the material through crack deflection, bridging effect and load transfer mechanism. At the same time, Fe2O3 in the red mud is partially reduced to Fe3O4 nanoparticles (magnetite) during the SPS process. This plastic phase further toughens the composite material through pinning effect and energy absorption. In addition, the calcium aluminosilicate glass phase (such as gehlenite and andradite) formed by CaO, Al2O3 and SiO2 in the red mud fills the particle gaps, optimizes the interfacial bonding and relieves stress concentration. The rapid sintering of SPS inhibits grain growth, forms a fine-grained structure, promotes ion diffusion through the electric field, reduces the reaction activation energy, and ensures the uniform distribution and high density of the reinforcing phase. Finally, the synergistic effect of these reinforcing phases (mullite, calcium hexaaluminate, oxide nanoparticles and glass phase) endows the composite material with excellent flexural properties while maintaining high hardness. And the doping of red mud reduces the sintering temperature of the ceramic. The influence of chromium oxide (Cr2O3) on the properties of alumina ceramics is mainly achieved through solid solution strengthening and grain boundary modification. Cr 3+ ions partially replace Al 3+ entering the Al2O3 lattice, causing lattice distortion and hindering dislocation movement, significantly improving the hardness and strength of the material. At the same time, Cr2O3 forms a (Cr,Al)2O3 solid solution at the grain boundary, optimizes the grain boundary bonding strength and inhibits abnormal grain growth, keeping the material in a fine-grained structure. In addition, the introduction of Cr2O3 can improve the sintering activity of Al2O3 ceramics, promote densification, and achieve functional modification while maintaining the excellent mechanical properties of the matrix.

[0056] As shown in Table 3, when x = 0.02, the red mud-alumina composite material prepared in this example has relatively excellent comprehensive properties, among which: the density is 97.02%; the Vickers hardness is 1885.35 HV; the flexural strength is 654.78 MPa; the fracture toughness is 16.41 MPa·m0.5.

[0057] Table 3 When x = 0.02, the red mud-alumina composite material prepared in this example has relatively excellent comprehensive properties

[0058]

[0059] Example 4

[0060] A preparation method of a red mud-doped alumina-based composite ceramic material, comprising the following steps:

[0061] (1) Using red mud, alumina, and titanium carbide powders as raw materials, mixing them according to the mass ratio of red mud:alumina:titanium carbide = 0.1(1.0 - x):0.9(1.0 - x):x, where x = (0.02, 0.04, 0.06, 0.08, 0.10).

[0062] (2) Place the mixed powder in a planetary ball mill. With a ball-to-powder ratio of 10:1, use absolute ethanol as the grinding medium, and ball mill for 24 h at a rotation speed of 200 r / min.

[0063] (3) Place the slurry obtained by ball milling in a vacuum drying oven and dry at 75 °C for 24 h. Crush it with a pulverizer and pass through a 200-mesh sieve to obtain the dried powder.

[0064] (4) Place the dried powder in a graphite mold and perform pre-pressing with a tablet press at a pressure of 15 MPa for 5 min.

[0065] (5) Place the graphite mold containing the green body in a spark plasma sintering furnace for sintering. The heating rate is 70 °C / min, and the sintering temperature is 1100 °C. The sintering pressure is 40 MPa, and the pressure value reaches the target pressure when the furnace temperature reaches the target temperature. After cooling with the furnace, the red mud-doped alumina-based composite ceramic material is obtained.

[0066] When preparing red mud-alumina composites by spark plasma sintering (SPS), the reaction mechanism for enhancing the flexural strength mainly depends on the synergistic effect of red mud and alumina, the rapid densification effect of SPS, and the formation of uniformly distributed reinforcing phases. The active SiO2, Fe2O3, and alkaline components (such as Na2O, CaO) in red mud are activated under high temperature and pulsed current, and undergo solid-phase reactions with alumina to form high-modulus mullite (3Al2O3·2SiO2) and calcium hexaaluminate (CaAl 12 O9). These needle-like or granular reinforcing phases are uniformly distributed in the matrix, and significantly improve the flexural strength of the material through crack deflection, bridging effect, and load transfer mechanisms. At the same time, Fe2O3 in red mud is partially reduced to Fe3O4 nanoparticles (magnetite) during the SPS process. This plastic phase further toughens the composite material through pinning effect and energy absorption. In addition, the calcium aluminosilicate glass phase (such as calcium aluminates and andradite) formed by CaO in red mud with Al2O3 and SiO2 fills the particle gaps, optimizes the interface bonding, and relieves stress concentration. The rapid sintering of SPS inhibits grain growth, forms a fine-grained structure, and promotes ion diffusion through the electric field, reducing the reaction activation energy, ensuring the uniform distribution and high density of the reinforcing phases. Finally, the synergistic effect of these reinforcing phases (mullite, calcium hexaaluminate, oxide nanoparticles, and glass phase) endows the composite material with excellent flexural properties while maintaining high hardness. The influence of chromium oxide (Cr2O3) on the properties of alumina ceramics is mainly achieved through solid solution strengthening and grain boundary modification. Cr 3+ ions partially replace Al 3+Entering the Al2O3 lattice, it causes lattice distortion and hinders dislocation movement, significantly improving the hardness and strength of the material. Moreover, the doping of red mud reduces the sintering temperature of the ceramic. The enhancement of the properties of alumina ceramics by titanium carbide (TiC) is mainly achieved through second-phase strengthening and interface optimization. TiC particles are uniformly dispersed in the Al2O3 matrix, inhibiting the growth of matrix grains through the pinning effect and forming a fine-grained structure; at the same time, the high-hardness TiC significantly improves the hardness and wear resistance of the material as a rigid reinforcing phase. The semi-coherent binding energy formed at the TiC / Al2O3 interface can effectively transfer the load and generate appropriate compressive stress during cooling due to the difference in thermal expansion coefficients, synergistically improving the fracture toughness and flexural strength of the material.

[0067] As shown in Table 4, the red mud-alumina composite material prepared in this example has excellent comprehensive properties, among which: the relative density is 96.89%; the Vickers hardness is 1532.35 HV; the flexural strength is 456.73 MPa; the fracture toughness is 7.86 MPa·m 0.5 。

[0068] Table 4 The red mud-alumina composite material prepared in this example has excellent comprehensive properties

[0069]

[0070] From the above test results, it can be seen that the red mud-alumina composite material prepared by the present invention has the advantages of high relative density, low sintering temperature, high Vickers hardness, high flexural strength and high fracture toughness. It not only overcomes some problems existing in alumina ceramics but also solves the problem of resource utilization of red mud.

[0071] Therefore, by adopting the above-mentioned method for the resource recycling of red mud, the present invention realizes the efficient utilization of red mud. Combined with alumina and auxiliary ceramics, the red mud-doped alumina-based composite ceramic material is prepared by processes such as high-energy ball milling and spark plasma sintering. The prepared material has the advantages of high toughness, high hardness and high strength.

[0072] 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 them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify or equivalently replace the technical solutions of the present invention, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for the resource recycling of red mud, characterized in that, It includes the following steps: Weigh the raw materials according to the raw material ratio, grind the raw materials into powder to obtain a mixed powder; the raw material ratio is 70% - 95% of matrix ceramic, 0.1% - 30% of auxiliary ceramic, and 0.1% - 30% of red mud; Place the mixed powder in a planetary ball mill, take it out after wet grinding, and place it in a vacuum drying oven for drying; Crush the dried powder with a crusher and pass it through a sieve; Load the sieved powder into a graphite mold for pre-pressing; Place the graphite mold containing the green body in a spark plasma sintering furnace for sintering. The furnace temperature rises from room temperature to the target temperature, and the pressure value reaches the target pressure when the furnace temperature reaches the target temperature. After cooling with the furnace, a red mud-doped alumina-based composite ceramic material is obtained.

2. The method for resource utilization of red mud according to claim 1, characterized in that The matrix ceramic is alumina; The auxiliary ceramic includes at least one of zirconia, titanium carbide, and chromium oxide.

3. The method for resource recycling of red mud according to claim 2, characterized in that The average particle size of the matrix ceramic is 100 - 300 nm; the average particle size of zirconia is 100 - 200 nm; the average particle size of titanium carbide is 30 - 60 μm; the average particle size of chromium oxide is 700 - 900 nm.

4. A method for the resource recycling of red mud according to claim 1, characterized in that, The mass ratio of balls to materials in the ball mill is 8 - 10:1, the rotation speed is 200 - 320 r / min, the wet grinding medium is anhydrous ethanol, and the ball milling time is 10 - 24 h.

5. A method for the resource recycling of red mud according to claim 1, characterized in that, The drying oven is a vacuum drying oven, the drying temperature is set at 70 - 85 °C, and the drying time is set at 24 h.

6. A method for the resource utilization of red mud according to claim 1, characterized in that, The pre-pressing pressure during pre-pressing is 15 - 25 MPa, and the pressure holding time is 5 - 10 min.

7. A method for the resource recycling of red mud according to claim 1, characterized in that, The heating rate is 70 - 80 °C / min, the target pressure is 30 - 50 MPa, the sintering time is 10 - 20 min, and the target temperature is 1050 °C - 1250 °C.

8. A composite ceramic prepared by the method for resource recycling of red mud according to claim 1.

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