Method for preparing porous ceramic through spontaneous solidification forming of emulsion

Abstract

The invention provides a method for preparing porous ceramic through spontaneous solidification forming of emulsion, and belongs to the technical field of porous ceramic materials. The method comprises the following steps: adding deionized water, an isobutylene and maleic anhydride copolymer, a defoaming agent, a plasticizer, a surface modifier and an oil phase into ceramic powder and / or sol nanoparticles, uniformly mixing, and mechanically stirring to obtain an emulsion with a spontaneous solidification characteristic; performing injection molding on the emulsion, performing spontaneous solidification molding at room temperature, and then performing drying and sintering to obtain the porous ceramic. According to the method, spontaneous solidification forming of the emulsion is achieved, the pore structure is regulated and controlled, the forming efficiency and quality are improved, and a new technical path is provided for large-scale and high-performance preparation of porous ceramics in complex shapes.

Description

Technical Field

[0001] This invention belongs to the field of porous ceramic materials technology, specifically relating to a method for preparing porous ceramics by spontaneous solidification of emulsion. Background Technology

[0002] Porous ceramics, with their high specific surface area, low density, high temperature resistance, corrosion resistance and excellent chemical stability, combined with the advantages of low thermal conductivity, low dielectric constant and high specific strength imparted by the porous structure, are widely used in gas / liquid filtration, catalyst carriers, biological scaffolds and heat exchangers. However, their application is still limited by insufficient control over the pore structure.

[0003] Currently, the main processes for preparing porous materials include organic foam impregnation, pore-forming agent addition, direct foaming, freeze-drying, and emulsion template methods. Among these, the emulsion template method, which uses emulsion droplets as pore-forming templates and forms porous structures through solvent removal, exhibits significant advantages in pore structure control. Specifically, by adjusting parameters such as emulsion type, phase ratio, emulsifier type, and dosage, gradient control of pore size from nanometer to micrometer scale can be achieved, meeting the differentiated needs of fields such as biomedicine and catalyst supports.

[0004] However, existing emulsion molding technology has significant technical bottlenecks: 1) Natural drying molding is inefficient, resulting in insufficient mechanical strength of the green body, and cracking defects are easily generated during drying shrinkage; 2) To improve the strength of the green body, auxiliary processes such as thermally initiated polymerization and freeze drying are usually required, but these methods rely excessively on external excitation conditions (such as temperature, pH, and chemical initiators), leading to reduced emulsion stability and structural instability phenomena such as droplet aggregation and phase separation, which seriously affect the uniformity of porosity and pore morphology. These defects restrict the application of emulsion molding in large-scale production, and there is an urgent need to develop a new, green, and efficient emulsion molding technology system to prepare porous materials.

[0005] Spontaneous solidification molding is an emerging ceramic colloidal molding technology. It uses a modified water-soluble isobutylene-maleic anhydride alternating copolymer as a dispersant for ceramic particles and a coagulant for the ceramic suspension. After standing, the suspension spontaneously solidifies to obtain a ceramic green body. The interaction between its molecular chains and solid particles forms a bridging network, enabling in-situ spontaneous solidification molding at room temperature. Ceramic products manufactured using spontaneous solidification molding include structural ceramics, foam ceramics, transparent ceramics, and plastic ceramics.

[0006] Chinese invention patent CN103130509A successfully developed a ceramic slurry with a solid content exceeding 50 vol.% based on an isobutylene-maleic anhydride alternating copolymer system. This slurry can spontaneously solidify at room temperature to form a highly dense green body. However, it suffers from defects such as low drying efficiency, green body cracking, and uneven density due to the high moisture content of the wet green body. Subsequent Chinese invention patent CN108748611A employed microwave-assisted technology to accelerate the gelation rate and water migration, while Chinese invention patent CN115448704B innovatively introduced a pressure-assisted process to achieve in-situ drainage. The synergistic optimization of these two technologies has led to their widespread application in the field of dense ceramics. Furthermore, the preparation of porous ceramics using spontaneous solidification technology is usually combined with high-temperature foaming agents and pore-forming agents to obtain a porous structure. This invention proposes using droplets as templates and utilizing spontaneous solidification to solidify and form a porous green body, eliminating the need for degreasing and overcoming problems such as pore wall defects caused by impurity residue and high-temperature decomposition.

[0007] However, there are no reports on introducing self-coagulating systems into emulsions to solidify and shape them for the preparation of porous ceramics. In particular, existing technologies struggle to achieve precise control of pore size, failing to meet the stringent requirements for pore uniformity in applications such as bioscaffolds and catalyst supports. The spontaneous coagulation technology for preparing porous ceramics from emulsions is not limited by material systems, is non-toxic and environmentally friendly, requires low dosage, eliminates the need for debinding, and produces excellent molding quality. This technology enables efficient in-situ solidification, providing a feasible new pathway for constructing large-size porous ceramics with uniform structure and controllable pore structure. Summary of the Invention

[0008] This invention addresses the challenge of preparing porous ceramics with complex shapes by proposing a method for preparing porous ceramics through spontaneous solidification of an emulsion. This invention utilizes hydrogen bonds formed between ceramic particles and the isobutylene-maleic anhydride copolymer. These hydrogen bonds collectively create a macromolecular network, thereby entangling the ceramic particles into a cohesive whole and achieving effective solidification of the continuous emulsion phase. The internal phase in the emulsion is removed during subsequent processing, resulting in in-situ pore formation. Simultaneously, the introduction of particles facilitates the formation of a relatively stable and uniformly dispersed system, preventing droplet aggregation and subsequent phase separation, thus enabling the control of the pore structure of the porous ceramic.

[0009] To achieve the above objectives, the specific technical solution of the present invention is as follows:

[0010] This invention provides a method for preparing porous ceramics by spontaneous solidification of emulsion, comprising the following steps:

[0011] S1. Add deionized water, isobutylene-maleic anhydride copolymer, defoamer, plasticizer, surface modifier and oil phase to ceramic powder and / or sol nanoparticles, mix evenly, and then mechanically stir to obtain an emulsion with spontaneous coagulation properties.

[0012] S2. The emulsion is poured into a mold and spontaneously solidified at room temperature, and then dried and sintered to obtain porous ceramics.

[0013] Optionally, in step S1, the amount of the isobutylene-maleic anhydride copolymer is 0.01-5 wt.% of the ceramic powder mass; the amount of the defoamer is 0.01-10 wt.% of the deionized water; the amount of the plasticizer is 0.01-10 wt.% of the deionized water; the amount of the surface modifier is 0-10.0 wt.% of the deionized water; the solid content of the emulsion is 5-85 wt.%; and the volume ratio of the oil phase to the deionized water is 1:19-99:1.

[0014] Optionally, in step S1, the ceramic powder is an oxide ceramic powder, a non-oxide ceramic powder, or a composite ceramic powder, selected from one or more of the following: alumina, silicon oxide, zirconium oxide, cerium oxide, magnesium oxide, yttrium oxide, titanium dioxide, hydroxyapatite, tricalcium β-phosphate, silicon nitride, silicon carbide, boron nitride, boron carbide, fly ash, coal gangue, secondary alumina ash, kaolin, tailings, and metallurgical slag.

[0015] The sol nanoparticles are one or a mixture of two or more of aluminum sol, silica sol, zirconium sol, titanium sol, and cerium sol.

[0016] Optionally, the isobutylene-maleic anhydride copolymer is a standard isobutylene-maleic anhydride copolymer, or an ammonium salt type, amide-ammonium salt type, imide type copolymer obtained by modification based thereon, or one or more mixtures of other modified isobutylene-maleic anhydride copolymers.

[0017] Optionally, the defoamer is one or a mixture of two or more of tert-butanol, polydimethylsiloxane, polyoxypropylene glycerol ether, and polyoxypropylene ethylene oxide glycerol ether.

[0018] Optionally, the plasticizer is one or a mixture of two or more of polyethylene glycol, polyvinyl alcohol, sodium pyrophosphate, sodium carboxymethyl cellulose, sodium carboxyethyl cellulose, polyvinylpyrrolidone, ethylene glycol, and glycerol.

[0019] Optionally, the surface modifier is one or a mixture of two or more of the following: sodium dodecyl sulfate, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, triethanolamine dodecyl sulfate, sodium α-alkenyl sulfonate, cocamidopropyl betaine, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, octadecanoic acid, superdispersant 41000 (full name Solsperse 41000, Chinese name Luborun), Tween series such as Tween 20 / 40 / 60 / 80, Span series such as Span 20 / 40 / 60 / 80, valeric acid, hexylamine, propyl gallate, trimethylchlorosilane, and sodium fatty alcohol polyoxyethylene ether sulfate.

[0020] Optionally, the oil phase is one or a mixture of two or more of the following: n-octane, n-hexane, n-decane, corn oil, toluene, styrene, n-heptane, cyclohexane, polydimethylsiloxane, glyceryl caprylate, liquid paraffin, silicone oil, soybean oil, rapeseed oil, and olive oil.

[0021] If the ceramic powder, sol nanoparticles, isobutylene-maleic anhydride copolymer, defoamer, plasticizer, surface modifier, and oil phase mentioned above are mixtures of two or more of the specific substances listed above, the proportion of the mixture can be arbitrary.

[0022] Optionally, in step S1, the mechanical stirring speed is 300-3000 rpm, and the time is 5 min-12 h.

[0023] Optionally, in step S2, the temperature for emulsion molding and drying is 15-80℃, and the time is 15 min-7 d; the heating rate during sintering is 0.1-20 ℃ / min, the sintering temperature is 800-2000 ℃, the sintering atmosphere is air, nitrogen or argon, and the holding time is 10 min-8 h.

[0024] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0025] This invention provides a method for preparing porous ceramics by spontaneous solidification of emulsion. During the molding process, oily droplets are uniformly dispersed in the ceramic emulsion. As the internal phase gradually evaporates, the droplets form a regular and uniform pore structure to meet the precise performance requirements of porous ceramics in different application scenarios.

[0026] Meanwhile, spontaneous solidification allows the emulsion to rapidly solidify at room temperature and pressure, eliminating the need for expensive equipment investment, significantly reducing production costs, simplifying the process, shortening the production cycle, and improving production efficiency. This makes the method more economical and feasible for large-scale industrial production of porous ceramics. Furthermore, this method is widely adaptable to ceramic materials, including traditional oxide ceramics such as alumina and zirconium oxide, as well as various non-oxide ceramics with special properties. By adjusting the type of emulsion, oil-water ratio, concentration of ceramic powder / sol nanoparticles, and coagulant formulation, high-quality porous ceramics can be prepared, providing strong technical support for the innovative development and application expansion of ceramic materials. Attached Figure Description

[0027] To more clearly illustrate the technical solution of this experimental example, the accompanying drawings in the description of the embodiments are now briefly explained.

[0028] Figure 1The image shows a SEM image of the porous silicon nitride ceramic preform prepared in Example 1.

[0029] Figure 2 This is a SEM image of the porous biphase calcium phosphate ceramic preform prepared in Example 2.

[0030] Figure 3 This is a macroscopic photograph of the porous biphase calcium phosphate ceramic preform prepared in Example 2.

[0031] Figure 4 The image shows a SEM image of the silicon nitride ceramic preform prepared in Comparative Example 2. Detailed Implementation

[0032] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the invention will be described in detail below with reference to specific embodiments. It should be understood that the selection of embodiments is merely an example of the feasibility of the technical solution and does not constitute any limitation on the invention.

[0033] Example 1

[0034] (1) Silicon nitride powder was added to a mixed solution consisting of deionized water, isobutylene-maleic anhydride copolymer, polydimethylsiloxane, polyvinyl alcohol, cocamidopropyl betaine, and n-octane, and the mixture was mechanically stirred at 3000 rpm for 1 h to obtain a stable emulsion. The isobutylene-maleic anhydride copolymer accounted for 0.01 wt.% of the silicon nitride powder, polydimethylsiloxane accounted for 7 wt.% of the deionized water, polyvinyl alcohol accounted for 10 wt.% of the deionized water, cocamidopropyl betaine accounted for 10.0 wt.% of the deionized water, the solid content of the emulsion was 20 wt.%, and the volume ratio of n-octane to deionized water was 2:1.

[0035] (2) The uniform and stable emulsion obtained by stirring above is injected into the mold, spontaneously solidified at room temperature, and dried at 15°C for 7 days to obtain silicon nitride ceramic blank. Figure 1 The image shows a SEM image of the porous silicon nitride ceramic preform prepared in Example 1. It can be seen that the preform already possesses a regular and uniform pore structure before sintering. The preform was sintered in a nitrogen atmosphere at a heating rate of 0.1 °C / min to 1900 °C and held for 10 min, yielding a porous silicon nitride ceramic with a porosity of 86.95%.

[0036] Example 2

[0037] (1) Hydroxyapatite and tricalcium phosphate powder were added to a mixed solution consisting of deionized water, ammonium salt isobutylene-maleic anhydride copolymer, tert-butanol, sodium carboxymethyl cellulose, sodium α-alkenyl sulfonate, and n-decane. The mixture was mechanically stirred at 1200 rpm for 8 h to obtain a stable emulsion. The ammonium salt isobutylene-maleic anhydride copolymer accounted for 0.5 wt.% of the ceramic powder, tert-butanol accounted for 10 wt.% of the deionized water, sodium carboxymethyl cellulose accounted for 5 wt.% of the deionized water, sodium α-alkenyl sulfonate accounted for 0% of the deionized water, the solid content of the emulsion was 55 wt.%, and the volume ratio of n-octane to deionized water was 10:1.

[0038] (2) The uniform and stable emulsion obtained by stirring above was injected into a mold and spontaneously solidified at room temperature. It was then dried at 80 °C for 15 min to obtain a composite green body of hydroxyapatite and tricalcium phosphate. In an air atmosphere, it was heated to 1250 °C at a heating rate of 5 °C / min and held for 2 h for sintering to obtain a porous duplex calcium phosphate ceramic with a porosity of 62.32%.

[0039] Figure 2 The image shows a SEM image of the porous biphase calcium phosphate ceramic green body prepared in Example 2, and... Figure 1 Similarly, it has a regular and uniform pore structure inside. Figure 3 This is a macroscopic photograph of the porous biphase calcium phosphate ceramic green body prepared in Example 2, illustrating that different molds can be selected to make the ceramic green body into various complex shapes.

[0040] Example 3

[0041] (1) A stable emulsion was prepared by adding silica powder to a mixed solution consisting of deionized water, an imide-type isobutylene-maleic anhydride copolymer, polyoxypropylene glycerol ether, polyvinylpyrrolidone, hexadecyltrimethylammonium chloride, and cyclohexane, and mechanically stirring at 300 rpm for 12 h. The imide-type amide-ammonium salt isobutylene-maleic anhydride copolymer accounted for 5 wt.% of the silica powder, polyoxypropylene glycerol ether accounted for 5 wt.% of the deionized water, polyvinylpyrrolidone accounted for 1 wt.% of the deionized water, hexadecyltrimethylammonium chloride accounted for 5 wt.% of the deionized water, the solid content of the emulsion was 85 wt.%, and the volume ratio of cyclohexane to deionized water was 1:19.

[0042] (2) The uniform and stable emulsion obtained by stirring above was injected into a mold and spontaneously solidified at room temperature. It was then dried at 50 °C for 48 h to obtain a ceramic green body. In an argon atmosphere, it was heated to 800 °C at a heating rate of 10 °C / min and held for 8 h to obtain a porous silica ceramic with a porosity of 40.20%.

[0043] Example 4

[0044] (1) Titanium sol nanoparticles were added to a mixed solution consisting of deionized water, amide-ammonium salt isobutylene and maleic anhydride copolymer, polyoxypropylene ethylene glycerol ether, polyethylene glycol, superdispersant 41000, and sunflower seed oil. The mixture was mechanically stirred at 2000 rpm for 5 min to obtain a stable emulsion. The amide-ammonium salt isobutylene and maleic anhydride copolymer accounted for 2 wt.% of the deionized water, polyoxypropylene ethylene glycerol ether accounted for 0.01 wt.% of the deionized water, polyethylene glycol accounted for 8 wt.% of the deionized water, superdispersant 41000 accounted for 8.5 wt.% of the deionized water, the solid content of the emulsion was 5 wt.%, and the volume ratio of sunflower seed oil to deionized water was 99:1.

[0045] (2) The uniform and stable emulsion obtained by stirring above was injected into a mold and spontaneously solidified at room temperature. It was then dried at 38 ℃ for 5 days to obtain a titanium dioxide ceramic green body. In an air atmosphere, it was heated to 1000 ℃ at a heating rate of 15 ℃ / min and held for 5 h for sintering to obtain a porous titanium dioxide ceramic with a porosity of 97.39%.

[0046] Example 5

[0047] (1) A mixture of fly ash and alumina sol nanoparticles was added to a mixed solution of deionized water, isobutylene-maleic anhydride copolymer, tert-butanol, sodium pyrophosphate, propyl gallate, and toluene. The mixture was mechanically stirred at 2500 rpm for 3 h to obtain a stable emulsion. The isobutylene-maleic anhydride copolymer accounted for 3.85 wt.% of the ceramic powder, tert-butanol accounted for 3 wt.% of the deionized water, sodium pyrophosphate accounted for 0.01 wt.% of the deionized water, propyl gallate accounted for 3.2 wt.% of the deionized water, the solid content of the emulsion was 68 wt.%, and the volume ratio of toluene to deionized water was 1:10.

[0048] (2) The uniform and stable emulsion obtained by stirring above was injected into a mold and spontaneously solidified at room temperature. It was then dried at 65 °C for 12 h to obtain a ceramic green body. In an air atmosphere, it was heated to 1650 °C at a heating rate of 20 °C / min and held for 6.5 h to obtain a porous multiphase ceramic with a porosity of 24.56%.

[0049] Comparative Example 1

[0050] (1) Silicon nitride powder was added to a mixed solution consisting of deionized water, isobutylene-maleic anhydride copolymer, polydimethylsiloxane, polyvinyl alcohol, hexylamine, and n-octane, and the mixture was mechanically stirred at 1500 rpm for 2 h to obtain a stable emulsion. The isobutylene-maleic anhydride copolymer accounted for 2 wt.% of the ceramic powder mass, polydimethylsiloxane accounted for 8 wt.% of the deionized water mass, polyvinyl alcohol accounted for 5 wt.% of the deionized water mass, hexylamine accounted for 2 wt.% of the deionized water mass, the solid content of the emulsion was 40 wt.%, and the volume ratio of n-octane to deionized water was 1:25.

[0051] (2) The uniform and stable emulsion obtained by stirring above was injected into a mold and spontaneously solidified at room temperature. After drying at 45 °C for 72 h, a silicon nitride ceramic green body was obtained. The porosity of the green body obtained by actual testing was 1.31%. This indicates that when the volume ratio of oil phase to deionized water is not within the parameter range of 1:19-99:1, the porous ceramic material provided by this invention cannot be obtained.

[0052] Comparative Example 2

[0053] (1) Silicon nitride powder was added to a mixed solution consisting of deionized water, isobutylene-maleic anhydride copolymer, polydimethylsiloxane, polyvinyl alcohol, hexadecyltrimethylammonium chloride, and n-octane, and the mixture was mechanically stirred at 1200 rpm for 1 h to obtain a stable emulsion. The isobutylene-maleic anhydride copolymer accounted for 3 wt.% of the ceramic powder mass, polydimethylsiloxane accounted for 5 wt.% of the deionized water mass, polyvinyl alcohol accounted for 4 wt.% of the deionized water mass, hexadecyltrimethylammonium chloride accounted for 8 wt.% of the deionized water mass, the solid content of the emulsion was 90 wt.%, and the volume ratio of n-octane to deionized water was 1:2.

[0054] (2) The uniform and stable emulsion obtained by stirring above is injected into the mold, spontaneously solidified at room temperature, and dried at 55 ℃ for 32 h to obtain silicon nitride ceramic blank. Figure 4 The image shows a SEM image of the silicon nitride ceramic green body prepared in Comparative Example 2, where a non-porous structure is formed. The actual measured porosity of the green body is 2.56%. This indicates that when the solid content in the emulsion is outside the parameter range of 5-85 wt.% specified in this invention, the porous ceramic material provided by this invention cannot be obtained.

[0055] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for preparing porous ceramics by spontaneous solidification of emulsion, characterized in that, Includes the following steps: S1. Add deionized water, isobutylene-maleic anhydride copolymer, defoamer, plasticizer, surface modifier and oil phase to ceramic powder and / or sol nanoparticles, mix evenly, and then mechanically stir to obtain an emulsion with spontaneous coagulation properties. S2. The emulsion is poured into a mold and spontaneously solidified at room temperature, and then dried and sintered to obtain porous ceramics.

2. The method for preparing porous ceramics by spontaneous solidification of emulsion according to claim 1, characterized in that, In step S1, the amount of the isobutylene-maleic anhydride copolymer is 0.01-5 wt.% of the ceramic powder mass; the amount of the defoamer is 0.01-10 wt.% of the deionized water; the amount of the plasticizer is 0.01-10 wt.% of the deionized water; the amount of the surface modifier is 0-10.0 wt.% of the deionized water; the solid content of the emulsion is 5-85 wt.%; and the volume ratio of the oil phase to the deionized water is 1:19-99:

1.

3. The method for preparing porous ceramics by spontaneous solidification of emulsion according to claim 1, characterized in that, In step S1, the ceramic powder is an oxide ceramic powder, a non-oxide ceramic powder, or a composite ceramic powder, selected from one or more of the following: alumina, silicon oxide, zirconium oxide, cerium oxide, magnesium oxide, yttrium oxide, titanium dioxide, hydroxyapatite, tricalcium β-phosphate, silicon nitride, silicon carbide, boron nitride, boron carbide, fly ash, coal gangue, secondary alumina ash, kaolin, tailings, and metallurgical slag. The sol nanoparticles are one or a mixture of two or more of aluminum sol, silica sol, zirconium sol, titanium sol, and cerium sol.

4. The method for preparing porous ceramics by spontaneous solidification of emulsion according to claim 1, characterized in that, In step S1, the isobutylene-maleic anhydride copolymer is a standard isobutylene-maleic anhydride copolymer, or an ammonium salt type, amide-ammonium salt type, imide type copolymer obtained by modification based on it, or one or more of other modified isobutylene-maleic anhydride copolymers.

5. The method for preparing porous ceramics by spontaneous solidification of emulsion according to claim 1, characterized in that, In step S1, the defoamer is one or a mixture of two or more of tert-butanol, polydimethylsiloxane, polyoxypropylene glycerol ether, and polyoxypropylene ethylene oxide glycerol ether.

6. The method for preparing porous ceramics by spontaneous solidification of emulsion according to claim 1, characterized in that, In step S1, the plasticizer is one or a mixture of two or more of polyethylene glycol, polyvinyl alcohol, sodium pyrophosphate, sodium carboxymethyl cellulose, sodium carboxyethyl cellulose, polyvinylpyrrolidone, ethylene glycol, and glycerol.

7. The method for preparing porous ceramics by spontaneous solidification of emulsion according to claim 1, characterized in that, In step S1, the surface modifier is one or a mixture of two or more of the following: sodium dodecyl sulfate, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, triethanolamine dodecyl sulfate, sodium α-alkenyl sulfonate, cocamidopropyl betaine, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, octadecanoic acid, superdispersant 41000, Tween series such as Tween 20 / 40 / 60 / 80, Span series such as Span 20 / 40 / 60 / 80, valeric acid, hexylamine, propyl gallate, trimethylchlorosilane, and sodium fatty alcohol polyoxyethylene ether sulfate.

8. The method for preparing porous ceramics by spontaneous solidification of emulsion according to claim 1, characterized in that, In step S1, the oil phase is one or a mixture of two or more of the following: n-octane, n-hexane, n-decane, corn oil, toluene, styrene, n-heptane, cyclohexane, polydimethylsiloxane, glyceryl caprylate, liquid paraffin, silicone oil, soybean oil, rapeseed oil, and olive oil.

9. The method for preparing porous ceramics by spontaneous solidification of emulsion according to claim 1, characterized in that, In step S1, the mechanical stirring speed is 300-3000 rpm, and the time is 5 min-12 h.

10. The method for preparing porous ceramics by spontaneous solidification of emulsion according to claim 1, characterized in that, In step S2, the temperature for emulsion molding and drying is 15-80℃, and the time is 15 min-7 d; the heating rate during sintering is 0.1-20 ℃ / min, the sintering temperature is 800-2000 ℃, the sintering atmosphere is air, nitrogen or argon, and the holding time is 10 min-8 h.

Images