CN114751730B - Porous mullite ceramic and preparation method thereof - Google Patents
Porous mullite ceramic and preparation method thereof Download PDFInfo
- Publication number
- CN114751730B CN114751730B CN202110183298.4A CN202110183298A CN114751730B CN 114751730 B CN114751730 B CN 114751730B CN 202110183298 A CN202110183298 A CN 202110183298A CN 114751730 B CN114751730 B CN 114751730B
- Authority
- CN
- China
- Prior art keywords
- crystalline silicon
- cutting waste
- porous mullite
- mullite ceramic
- ceramic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/16—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silicates other than clay
- C04B35/18—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silicates other than clay rich in aluminium oxide
- C04B35/185—Mullite 3Al2O3-2SiO2
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/62204—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products using waste materials or refuse
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3217—Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3217—Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
- C04B2235/3218—Aluminium (oxy)hydroxides, e.g. boehmite, gibbsite, alumina sol
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
- C04B2235/3256—Molybdenum oxides, molybdates or oxide forming salts thereof, e.g. cadmium molybdate
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/42—Non metallic elements added as constituents or additives, e.g. sulfur, phosphor, selenium or tellurium
- C04B2235/428—Silicon
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
- C04B2235/6567—Treatment time
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
- C04B2235/9607—Thermal properties, e.g. thermal expansion coefficient
- C04B2235/9615—Linear firing shrinkage
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/60—Production of ceramic materials or ceramic elements, e.g. substitution of clay or shale by alternative raw materials, e.g. ashes
Abstract
The invention provides a porous mullite ceramic and a preparation method thereof, wherein the porous mullite ceramic comprises the following raw materials: the mass ratio of the mixed powder to the adhesive is 100; the mixed powder comprises crystalline silicon cutting waste, an aluminum source and a molybdenum additive in a mass ratio of 10-25; the silicon cutting waste material contains 90-97% of silicon; the molybdenum-based additive is selected from one or more of molybdenum trioxide, ammonium molybdate, ammonium paramolybdate and aluminum molybdate. The method takes the crystal silicon cutting waste as the silicon source, thereby not only changing waste into valuable and reducing the cost, but also generating corresponding environmental benefit. The porous mullite ceramic with the characteristics of mullite crystal bar cross-linking interlocking structure, higher bending strength and higher porosity is obtained by adopting a molybdenum additive and performing reactive sintering. The volume increment brought by the oxidation of the crystalline silicon waste compensates the sintering shrinkage of the ceramic, so that the linear dimension change rate of the ceramic is-0.89-1.86%.
Description
Technical Field
The invention relates to the technical field of porous ceramics, in particular to porous mullite ceramic and a preparation method thereof.
Background
Solar energy is a green, clean, renewable energy source, and the photovoltaic industry, which converts solar energy into electrical energy, is rapidly developing. Solar cells prepared by taking monocrystalline silicon wafers and polycrystalline silicon wafers as elements have led to the global photovoltaic market for many years. The traditional crystal silicon wafer cutting mode is mortar cutting containing silicon carbide abrasive materials, and the diamond wire cutting process is a crystal silicon wafer cutting mode which is newly appeared and is gradually dominant in recent years. During the cutting of the silicon ingot into crystalline silicon wafers by the diamond wire, about 40% of the crystalline silicon is wasted in the form of sawdust. Because organic additives, peeled diamond particles and metal chips which are introduced as cutting fluid in the cutting process can be mixed with the crystalline silicon chips, and the purity requirement of the crystalline silicon of the solar crystalline silicon plate is extremely high (6N level), the crystalline silicon chips generated in the cutting process are difficult to be recycled. The direct discarding of the crystalline silicon cutting waste material causes environmental pollution and wastes valuable resources in the waste material. Therefore, the research on the recycling way of the crystal silicon cutting waste can realize the purpose of changing waste into valuable and can also generate better environmental benefit.
Currently, in the research on recycling of diamond wire-electrode cutting crystalline silicon waste materials, there are various secondary utilization methods such as recovery and purification into pure silicon, synthesis of silicon nitride after pretreatment, preparation of silicon electrode materials after purification, and the like. These recovery methods generally require pretreatment processes such as acid washing or high-temperature impurity removal under a protective atmosphere, and these processes cause certain environmental pollution and energy consumption. Therefore, if the crystalline silicon cutting waste can be directly utilized after being simply treated, the method has important significance for realizing secondary full utilization of the crystalline silicon cutting waste, reducing environmental pollution and reducing energy consumption.
Disclosure of Invention
In view of the above, the present invention aims to provide a porous mullite ceramic and a preparation method thereof, wherein crystalline silicon cutting waste is used as a silicon source in the preparation process, and the prepared porous mullite ceramic has a low linear dimension change rate.
The invention provides a porous mullite ceramic, which comprises the following raw materials:
the mass ratio of the mixed powder to the adhesive is 100;
the mixed powder comprises crystalline silicon cutting waste, an aluminum source and a molybdenum additive in a mass ratio of 10-25;
the crystalline silicon cutting waste contains 90-97% of silicon;
the molybdenum-based additive is one or more selected from molybdenum trioxide, ammonium molybdate, ammonium paramolybdate and aluminum molybdate.
Preferably, the aluminium source is selected from one or more of aluminium oxide, aluminium hydroxide, a calcined product of aluminium hydroxide at 300-800 ℃, diaspore, pseudo-diaspore and bauxite.
Preferably, the grain size of the crystalline silicon cutting waste material is less than 200 meshes.
Preferably, the binder is selected from one or more of water, a sodium carboxymethylcellulose (CMC) aqueous solution with a mass fraction of 1-6%, and a polyvinyl alcohol (PVA) aqueous solution with a mass fraction of 1-6%.
The invention provides a preparation method of the porous mullite ceramic in the technical scheme, which comprises the following steps:
pretreating waste materials generated by cutting crystalline silicon by diamond wires to obtain pretreated crystalline silicon cutting waste materials;
mixing the pretreated crystal silicon cutting waste with an aluminum source and a molybdenum additive to obtain mixed powder;
adding an adhesive into the mixed powder, and pressing to obtain a green body;
and drying and degreasing the green body, and sintering in an air atmosphere to obtain the porous mullite ceramic.
Preferably, the pre-treatment comprises the steps of:
and grinding waste materials generated by cutting the crystalline silicon by the diamond wire, washing with water, drying, grinding again, and sieving by a 200-mesh sieve to obtain the pretreated crystalline silicon cutting waste materials.
Preferably, the mixing mode is ball milling mixing with a ball-to-material ratio of 10.
Preferably, the temperature of the drying and degreasing treatment is 120-150 ℃, and the time of the drying and degreasing treatment is 15-20 h.
Preferably, the sintering temperature is 800-1000 ℃ and the sintering time is 2-5 h.
The invention provides a porous mullite ceramic, which comprises the following raw materials: the mass ratio of the mixed powder to the adhesive is 100; the mixed powder comprises crystalline silicon cutting waste, an aluminum source and a molybdenum additive in a mass ratio of 10-25; the crystalline silicon cutting waste contains 90-97% of silicon; the molybdenum-based additive is one or more selected from molybdenum trioxide, ammonium molybdate, ammonium paramolybdate and aluminum molybdate. The method takes the crystalline silicon cutting waste as the silicon source for preparing the porous mullite ceramic, is a secondary utilization of the crystalline silicon cutting waste, can realize the purpose of changing waste into valuable, reduces the production cost of the porous mullite ceramic, and can generate corresponding environmental benefits. Meanwhile, compared with the conventional secondary utilization of the crystalline silicon cutting waste, the method does not need to carry out complex pretreatment processes such as acid washing impurity removal, high-temperature reduction and the like on the crystalline silicon cutting waste, simplifies the process flow, and can completely dry and squeeze the crystalline silicon cutting waste at one time. The metallic silicon in the crystalline silicon cutting waste can be oxidized to generate amorphous silicon dioxide with high reaction activity in the calcining process, has a promoting effect on the reaction sintering with alumina, and is an excellent silicon source for preparing the porous mullite ceramic at low temperature. In addition, after the metal silicon is oxidized into silicon dioxide, the volume is greatly increased, which can compensate sintering shrinkage frequently generated during ceramic sintering, so that the linear dimension change rate of the sample before and after sintering is extremely low. The porous mullite ceramic with the mullite crystal bar cross-linking interlocking structure can be obtained by adopting the molybdenum additive as a catalyst or a catalyst precursor of the mullite reaction and performing reaction sintering at a lower temperature. In a word, the invention realizes the clean and harmless utilization of the crystal silicon cutting waste material and also realizes the preparation of the mullite porous ceramic with low cost, low energy consumption and environmental protection.
Drawings
FIG. 1 is an X-ray diffraction pattern of a porous mullite ceramic made in accordance with example 1 of the present invention;
FIG. 2 is a scanning electron microscope cross-sectional view of the porous mullite ceramic made in accordance with example 1 of the present invention.
Detailed Description
The invention provides a porous mullite ceramic, which comprises the following raw materials:
the mass ratio of the mixed powder to the adhesive is 100;
the mixed powder comprises crystalline silicon cutting waste, an aluminum source and a molybdenum additive in a mass ratio of 10-25;
the crystalline silicon cutting waste contains 90-97% of silicon;
the molybdenum-based additive is selected from one or more of ammonium molybdate, ammonium metamolybdate and aluminum molybdate.
The preparation raw materials of the porous mullite ceramic provided by the invention comprise mixed powder; the mixed powder comprises crystalline silicon cutting waste, an aluminum source and a molybdenum additive in a mass ratio of 10-25; the crystalline silicon cutting waste material contains 90-97% of silicon.
In the invention, the crystalline silicon cutting waste contains 90-97% of silicon simple substance; the granularity of the crystalline silicon cutting waste is less than 200 meshes. The crystal silicon cutting waste is a commercial product.
In the present invention, the aluminum source is selected from one or more of aluminum oxide, aluminum hydroxide, a calcined product of aluminum hydroxide at 300 to 800 ℃, diaspore, pseudo-diaspore and bauxite. In specific examples, the aluminum source is aluminum oxide, a product of calcining aluminum hydroxide at 450 ℃, a product of calcining aluminum hydroxide at 800 ℃, or a mixture of bauxite and aluminum oxide in a mass ratio of 1.
The molybdenum additive is one or more selected from molybdenum trioxide, ammonium molybdate, ammonium paramolybdate and aluminum molybdate. In a specific embodiment, the molybdenum additive is molybdenum trioxide, ammonium molybdate or ammonium metapholybdate.
In the invention, the adhesive is selected from one or more of water, CMC aqueous solution with the mass fraction of 1-6% and PVA aqueous solution with the mass fraction of 1-6%. In a specific embodiment, the binder is an aqueous solution of CMC with a mass fraction of 3%.
In the present invention, the mass ratio of the mixed powder to the binder is 100; in a specific embodiment, the mass ratio of the mixed powder to the binder is 30.
In the specific embodiment, the mass ratio of the crystalline silicon cutting waste material to the aluminum source to the molybdenum additive is 10; or 10.6; or 10; or 10; or 10.
The invention provides a preparation method of the porous mullite ceramic in the technical scheme, which comprises the following steps:
pretreating waste materials generated by cutting crystalline silicon by diamond wires to obtain pretreated crystalline silicon cutting waste materials;
mixing the pretreated crystal silicon cutting waste with an aluminum source and a molybdenum additive to obtain mixed powder;
adding an adhesive into the mixed powder, and pressing to obtain a green body;
and drying and degreasing the green body, and sintering in an air atmosphere to obtain the porous mullite ceramic.
In the present invention, the pretreatment preferably comprises the steps of:
and grinding waste materials generated by cutting the crystalline silicon by the diamond wire, washing, drying, grinding again, and sieving by a 200-mesh sieve to obtain the pretreated crystalline silicon cutting waste materials. The invention is preferably ground to 80 mesh and washed with water.
The mixing mode is ball-milling mixing according to the ball-to-material ratio of 10. In the specific example, the time for ball milling mixing is 4h.
The temperature of the drying and degreasing treatment is 120-150 ℃, and the time of the drying and degreasing treatment is 15-20 h. In a specific embodiment, the temperature for drying and degreasing is 120 ℃; the time is 20h.
The sintering is carried out in an air atmosphere; the sintering temperature is 800-1000 ℃, and the sintering time is 2-5 h. The sintering is preferably carried out for 0.5h at 800 ℃, and the temperature is continuously raised to 900 ℃ or 1000 ℃ for 3h; or keeping the temperature at 800 ℃ for 3.5h.
The invention provides a method for preparing porous mullite ceramic by using crystalline silicon cutting waste, which recycles the crystalline silicon cutting waste, reduces the preparation cost of mullite, and also reduces the environmental burden; the method provided by the invention can prepare the porous mullite ceramic with higher porosity and bending strength at lower temperature. The metallic silicon in the crystalline silicon cutting waste material can be oxidized into silicon dioxide in the sintering process, the volume can be gradually increased along with the reaction, the compensation effect on the sintering shrinkage which often occurs in the ceramic sintering process can be realized, and the linear dimension change rate of the sample size before and after sintering is extremely low. According to the method, waste materials generated by cutting crystalline silicon by diamond wires are used as silicon sources, and after the silicon sources are mixed with an aluminum source and a molybdenum-series additive, a pore-forming agent is not required to be added additionally, and the porous mullite ceramic with the mullite crystal bar cross-linking interlocking structure can be prepared by low-temperature sintering in the air atmosphere.
The porosity of the porous mullite ceramic is obtained by testing in a distilled water medium based on the Archimedes principle;
the bending strength of the porous mullite ceramic is calculated according to a GB/T1965-1996 porous ceramic bending strength test method.
The rate of change in the linear dimension of the porous ceramic is calculated by the following formula:
in the formula:
S 0 linear dimensional change, positive values representing linear expansion and negative values representing linear shrinkage
L 0 Green radial length
L-radial length of sample after sintering
In order to further illustrate the present invention, the following examples are provided to describe in detail the porous mullite ceramic and the method for preparing the same, but they should not be construed as limiting the scope of the present invention.
Example 1
Step one, grinding 200g of crystalline silicon cutting waste into powder, enabling the crystalline silicon cutting waste to completely pass through a 80-mesh sieve, then adding the crystalline silicon cutting waste into 1kg of deionized water, stirring for two hours, carrying out solid-liquid separation in a suction filtration mode, drying a filter cake, repeating the processes, grinding the finally obtained crystalline silicon cutting waste into powder, and sieving the powder through the 200-mesh sieve;
and step two, ball-milling 10g of the crystalline silicon cutting waste pretreated in the step one, 52.32g of alumina and 13.8g of ammonium molybdate for 4 hours according to a ball-to-material ratio of 10.
And step three, taking 60g of the mixed powder obtained in the step two, adding 2g of CMC aqueous solution with the mass fraction of 3 percent as an adhesive, uniformly mixing, pressing into a green body, and treating the green body for 20 hours at the temperature of 120 ℃.
And step four, putting the green body treated in the step three into a muffle furnace for calcination, wherein the calcination condition is that the temperature is kept at 800 ℃ for 0.5h, and the temperature is continuously raised to 900 ℃ for 3h, so that the porous mullite ceramic is obtained. The test shows that the porosity of the porous mullite ceramic is 42.11 percent, the bending strength is 44.33MPa, and the linear expansion coefficient is 0.47 percent.
The porous mullite ceramic obtained by sintering is characterized by an X-ray diffractometer, and the result is shown in figure 1. As seen in FIG. 1, when sintering is carried out at 900 deg.C, the mullite phase is already formed and highly crystallized, and the reactants are reacted completely.
The fracture morphology of the porous mullite ceramic obtained by sintering is characterized by a scanning electron microscope, and the result is shown in figure 2. As shown in FIG. 2, after sintering at 900 ℃, the prepared porous mullite ceramic has a microstructure of mullite rod cross-linking and interlocking, and no obvious glass phase exists.
Example 2
Step one, grinding 200g of the crystalline silicon cutting waste into powder, enabling the crystalline silicon cutting waste to completely pass through a sieve of 80 meshes, then adding the crystalline silicon cutting waste into 1kg of deionized water, stirring for two hours, carrying out solid-liquid separation in a suction filtration mode, drying a filter cake, repeating the processes, grinding the finally obtained crystalline silicon cutting waste into powder, and sieving the powder through a sieve of 200 meshes.
And step two, calcining aluminum hydroxide at 450 ℃, taking 61.6g of calcined product as an aluminum source, and ball-milling the calcined product, 10g of the pretreated crystal silicon cutting waste in the step one and 9.2g of ammonium molybdate for 4 hours according to a ball-to-material ratio of 10.
And step three, taking 60g of the mixed powder obtained in the step two, adding 2g of CMC aqueous solution with the mass fraction of 3 percent as a bonding agent, uniformly mixing, pressing into a green body, and treating the green body at 120 ℃ for 20 hours.
And step four, putting the green body treated in the step three into a muffle furnace for calcination, wherein the calcination condition is to keep the temperature at 800 ℃ for 0.5h, continuously heating to 1000 ℃ and keeping the temperature for 3h, and sintering to obtain the porous mullite ceramic. The test shows that the porosity of the porous mullite ceramic is 50.89%, the bending strength is 40.77MPa, and the linear expansion rate is 0.62%.
Example 3
Step one, grinding 200g of crystal silicon cutting waste into powder, enabling the crystal silicon cutting waste to completely pass through a sieve of 80 meshes, then adding the crystal silicon cutting waste into 1kg of deionized water, stirring for two hours, carrying out solid-liquid separation in a suction filtration mode, drying a filter cake, repeating the processes, grinding the finally obtained crystal silicon cutting waste into powder, and sieving the powder through a sieve of 200 meshes.
And step two, calcining aluminum hydroxide at 800 ℃, taking 52.32g of calcined product as an aluminum source, and ball-milling 10g of the crystal silicon cutting waste pretreated in the step one and 13.8g of ammonium molybdate for 4 hours according to a ball-to-material ratio of 10.
And step three, taking 60g of the mixed powder obtained in the step two, adding 2g of CMC aqueous solution with the mass fraction of 3 percent as a bonding agent, uniformly mixing, pressing into a green body, and treating the green body at 120 ℃ for 20 hours.
And step four, putting the green body treated in the step three into a muffle furnace for calcination, wherein the calcination condition is that the temperature is kept at 800 ℃ for 3.5 hours, and sintering to obtain the porous mullite ceramic. The test shows that the porosity of the porous mullite ceramic is 44.39%, the bending strength is 31.67MPa, and the linear expansion rate is 1%.
Example 4
Step one, grinding 200g of the crystalline silicon cutting waste into powder, enabling the crystalline silicon cutting waste to completely pass through a sieve of 80 meshes, then adding the crystalline silicon cutting waste into 1kg of deionized water, stirring for two hours, carrying out solid-liquid separation in a suction filtration mode, drying a filter cake, repeating the processes, grinding the finally obtained crystalline silicon cutting waste into powder, and sieving the powder through a sieve of 200 meshes.
And step two, ball-milling 10g of the crystal silicon cutting waste pretreated in the step one, 52.32g of alumina and 4.6g of ammonium metamolybdate for 4 hours according to the ball-to-material ratio of 10.
And step three, taking 60g of the mixed powder obtained in the step two, adding 2g of CMC aqueous solution with the mass fraction of 3 percent as an adhesive, uniformly mixing, pressing into a green body, and treating the green body for 20 hours at the temperature of 120 ℃.
And step four, putting the green body treated in the step three into a muffle furnace for calcination, wherein the calcination condition is to keep the temperature at 800 ℃ for 0.5h, continuously heating to 1000 ℃ and keeping the temperature for 3h, and sintering to obtain the porous mullite ceramic. The test shows that the porosity of the porous mullite ceramic is 41.28 percent, the bending strength is 43.79MPa, and the linear expansion coefficient is 0.25 percent.
Example 5
Step one, grinding 200g of the crystalline silicon cutting waste into powder, enabling the crystalline silicon cutting waste to completely pass through a sieve of 80 meshes, then adding the crystalline silicon cutting waste into 1kg of deionized water, stirring for two hours, carrying out solid-liquid separation in a suction filtration mode, drying a filter cake, repeating the processes, grinding the finally obtained crystalline silicon cutting waste into powder, and sieving the powder through a sieve of 200 meshes.
And step two, ball-milling 10g of the crystal silicon cutting waste pretreated in the step one, 52.32g of alumina and 9.2g of ammonium molybdate for 4 hours according to the ball-to-material ratio of 10.
And step three, taking 60g of the mixed powder obtained in the step two, adding 2g of CMC aqueous solution with the mass fraction of 3 percent as a bonding agent, uniformly mixing, pressing into a green body, and treating the green body at 120 ℃ for 20 hours.
And step four, putting the green body treated in the step three into a muffle furnace for calcination, wherein the calcination condition is that the temperature is kept at 800 ℃ for 0.5h, the temperature is continuously raised to 900 ℃ for 3h, and the porous mullite ceramic is obtained by sintering. The test shows that the porosity of the porous mullite ceramic is 40.93 percent, the bending strength is 53.18MPa, and the linear expansion coefficient is 0.51 percent.
Example 6
Step one, grinding 200g of crystal silicon cutting waste into powder, enabling the crystal silicon cutting waste to completely pass through a sieve of 80 meshes, then adding the crystal silicon cutting waste into 1kg of deionized water, stirring for two hours, carrying out solid-liquid separation in a suction filtration mode, drying a filter cake, repeating the processes, grinding the finally obtained crystal silicon cutting waste into powder, and sieving the powder through a sieve of 200 meshes.
And step two, ball-milling 10g of the crystal silicon cutting waste pretreated in the step one, 15g of bauxite, 45g of alumina and 9.2g of ammonium molybdate for 4 hours according to the ball-to-material ratio of 10.
And step three, taking 60g of the mixed powder obtained in the step two, adding 2g of CMC aqueous solution with the mass fraction of 3 percent as an adhesive, uniformly mixing, pressing into a green body, and treating the green body for 20 hours at the temperature of 120 ℃.
And step four, putting the green body treated in the step three into a muffle furnace for calcination, wherein the calcination condition is to keep the temperature at 800 ℃ for 0.5h, continuously heating to 1000 ℃ and keeping the temperature for 3h, and sintering to obtain the porous mullite ceramic. The test shows that the porosity of the porous mullite ceramic is 43.21 percent, the bending strength is 47.62MPa, and the linear shrinkage rate is 0.89 percent.
Example 7
Grinding 200g of the crystalline silicon cutting waste into powder, enabling the crystalline silicon cutting waste to completely pass through a sieve of 80 meshes, then adding the crystalline silicon cutting waste into 1kg of deionized water, stirring for two hours, carrying out solid-liquid separation in a suction filtration mode, drying a filter cake, repeating the processes, grinding the finally obtained crystalline silicon cutting waste into powder, and sieving the powder through a sieve of 200 meshes.
And step two, ball-milling 10g of the crystal silicon cutting waste pretreated in the step one, 52.32g of alumina and 9.2g of molybdenum trioxide according to a ball-to-material ratio of 10.
And step three, taking 60g of the mixed powder obtained in the step two, adding 2g of CMC aqueous solution with the mass fraction of 3 percent as an adhesive, uniformly mixing, pressing into a green body, and treating the green body for 20 hours at the temperature of 120 ℃.
And step four, placing the green body treated in the step three into a muffle furnace for calcination under the condition of keeping the temperature at 800 ℃ for 0.5h, continuously heating to 900 ℃ and keeping the temperature for 3h, and sintering to obtain the porous mullite ceramic. The test shows that the porosity of the porous mullite ceramic is 46.57 percent, the bending strength is 22.77MPa, and the linear expansion coefficient is 1.86 percent.
According to the embodiment, the invention provides the porous mullite ceramic, which comprises the following raw materials of mixed powder and a binding agent in a mass ratio of 100; the mixed powder comprises crystalline silicon cutting waste, an aluminum source and a molybdenum additive in a mass ratio of 10-25; the crystalline silicon cutting waste contains 90-97% of silicon; the molybdenum additive is one or more selected from molybdenum trioxide, ammonium molybdate, ammonium paramolybdate and aluminum molybdate. The method takes the crystalline silicon cutting waste as the silicon source for preparing the porous mullite ceramic, is a secondary utilization of the crystalline silicon cutting waste, can realize the purpose of changing waste into valuable, reduces the production cost of the porous mullite ceramic, and can generate corresponding environmental benefits. Meanwhile, compared with the secondary utilization of the conventional crystalline silicon cutting waste material, the method does not need to carry out complex pretreatment processes such as acid washing impurity removal, high-temperature reduction and the like on the crystalline silicon cutting waste material, simplifies the process flow and can completely dry and squeeze the crystalline silicon cutting waste material once. The metal silicon in the crystalline silicon cutting waste material can be oxidized in the calcining process to generate amorphous silicon dioxide with high reaction activity, has a promoting effect on the reaction sintering with alumina, and is an excellent silicon source for preparing the porous mullite ceramic at low temperature. In addition, after the metal silicon is oxidized into silicon dioxide, the volume is greatly increased, which can compensate sintering shrinkage frequently generated during ceramic sintering, so that the linear dimension change rate of the sample before and after sintering is extremely low. The porous mullite ceramic with the mullite crystal bar cross-linking interlocking structure can be obtained by adopting the molybdenum substance as the catalyst or the catalyst precursor of the mullite reaction and performing reaction sintering at a lower temperature. In a word, the invention realizes the clean and harmless utilization of the crystal silicon cutting waste material and also realizes the preparation of the mullite porous ceramic with low cost, low energy consumption and environmental protection. The experimental results show that: after sintering at 800-1000 deg.c, the porous mullite ceramic has porosity of 40.93-50.89%, bending strength of 22.77-53.18 MPa and linear size change rate of-0.89-1.86%.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and amendments can be made without departing from the principle of the present invention, and these modifications and amendments should also be considered as the protection scope of the present invention.
Claims (9)
1. The porous mullite ceramic is prepared from the following raw materials:
the mass ratio of the mixed powder to the adhesive is 100;
the mixed powder comprises a crystalline silicon cutting waste material, an aluminum source and a molybdenum additive in a mass ratio of 10 to 25;
the silicon cutting waste material contains 90-97% of silicon;
the molybdenum additive is one or more selected from molybdenum trioxide, ammonium molybdate, ammonium paramolybdate and aluminum molybdate;
the porosity of the porous mullite ceramic is 40.93-50.89%, and the linear dimension change rate is-0.89-1.86%.
2. The porous mullite ceramic of claim 1, wherein the aluminum source is selected from one or more of aluminum oxide, aluminum hydroxide, a calcined product of aluminum hydroxide at 300 to 800 ℃, gibbsite and bauxite.
3. The porous mullite ceramic of claim 1, wherein the crystalline silicon cut waste has a particle size of less than 200 mesh.
4. The porous mullite ceramic according to claim 1, wherein the binder is selected from one or more of water, an aqueous solution of sodium carboxymethylcellulose with a mass fraction of 1 to 6%, and an aqueous solution of polyvinyl alcohol with a mass fraction of 1 to 6%.
5. A preparation method of the porous mullite ceramic disclosed by any one of claims 1 to 4 comprises the following steps:
pretreating waste materials generated by cutting crystalline silicon by diamond wires to obtain pretreated crystalline silicon cutting waste materials;
mixing the pretreated crystal silicon cutting waste with an aluminum source and a molybdenum additive to obtain mixed powder;
adding an adhesive into the mixed powder, and pressing to obtain a green body; and drying and degreasing the green body, and sintering in an air atmosphere to obtain the porous mullite ceramic.
6. The method for preparing according to claim 5, wherein the pretreatment comprises the steps of:
and grinding waste materials generated by cutting the crystalline silicon by the diamond wire, washing with water, drying, grinding again, and sieving by a 200-mesh sieve to obtain the pretreated crystalline silicon cutting waste materials.
7. The preparation method of claim 5, wherein the mixing is performed by ball milling at a ball-to-feed ratio of 10 to 1, and the ball-milling mixing time is 3.5 to 4.5 hours.
8. The preparation method according to claim 5, wherein the temperature of the drying and degreasing treatment is 120 to 150 ℃, and the time of the drying and degreasing treatment is 15 to 20h.
9. The production method according to claim 5, wherein the sintering is performed under an air atmosphere; the sintering temperature is 800 to 1000 ℃, and the sintering time is 2 to 5h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110183298.4A CN114751730B (en) | 2021-02-10 | 2021-02-10 | Porous mullite ceramic and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110183298.4A CN114751730B (en) | 2021-02-10 | 2021-02-10 | Porous mullite ceramic and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114751730A CN114751730A (en) | 2022-07-15 |
| CN114751730B true CN114751730B (en) | 2023-04-11 |
Family
ID=82325678
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110183298.4A Active CN114751730B (en) | 2021-02-10 | 2021-02-10 | Porous mullite ceramic and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114751730B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107365156A (en) * | 2017-07-19 | 2017-11-21 | 北京科技大学 | A kind of method that silicon nitride is prepared using diamond wire saw polycrystalline silicon wastes |
| CN109851378A (en) * | 2018-12-28 | 2019-06-07 | 天津大学 | Preparation method of ceramic matrix fiber composite sealing gasket |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0992467B1 (en) * | 1998-10-01 | 2003-02-12 | Corning Incorporated | Production of porous mullite bodies |
| CN104072160B (en) * | 2014-05-14 | 2015-09-09 | 山东嘉腾实业有限公司 | Ultralow pore mullite brick |
| CN106904939B (en) * | 2017-03-27 | 2020-04-03 | 河南科技大学 | Coal gangue doped high-strength ceramic floor tile and preparation process thereof |
| CN107010973B (en) * | 2017-05-10 | 2020-05-19 | 济南大学 | Light complex-phase porous heat-insulating refractory material, mullite refractory material and preparation method thereof |
| CN110240483B (en) * | 2018-03-07 | 2021-10-19 | 海南大学 | Method for preparing silicon carbide porous ceramic by using crystalline silicon waste mortar |
| CN111807817B (en) * | 2020-07-23 | 2022-07-05 | 明光市铭垚凹凸棒产业科技有限公司 | Mullite whisker-attapulgite porous ceramic with high specific surface area and preparation method thereof |
-
2021
- 2021-02-10 CN CN202110183298.4A patent/CN114751730B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107365156A (en) * | 2017-07-19 | 2017-11-21 | 北京科技大学 | A kind of method that silicon nitride is prepared using diamond wire saw polycrystalline silicon wastes |
| CN109851378A (en) * | 2018-12-28 | 2019-06-07 | 天津大学 | Preparation method of ceramic matrix fiber composite sealing gasket |
Non-Patent Citations (1)
| Title |
|---|
| Mingzhao Liu et al..Development of highly porous mullite whisker ceramic membranes for oil-in-water separation and resource utilization of coal gangue.《Separation and Purification Technology》.2019,第237卷1-10页. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114751730A (en) | 2022-07-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104556022B (en) | It is a kind of that the method for expanding microcrystalline graphite material is prepared with micro crystal graphite | |
| CN103819219B (en) | Acid and alkali corrosion-resistant silicon carbide porous support | |
| CN104328478A (en) | Preparation method of SiC crystal whisker | |
| CN108585779B (en) | Method for preparing aluminum-silicon composite material by using gasified slag | |
| JP2010173916A (en) | Method of manufacturing silicon carbide from silicon waste | |
| CN103553647B (en) | Method for preparation of silicon nitride bonded silicon carbide refractory material by using silicon cutting waste mortar | |
| CN111847475A (en) | Preparation method of 13X molecular sieve and 13X molecular sieve | |
| CN106745134A (en) | A kind of method of sapphire diamond wire cutting waste material recycling | |
| CN110818297A (en) | Method for preparing α type high-strength gypsum by microwave irradiation of phosphogypsum crystal transformation under normal pressure | |
| CN104150911B (en) | A kind of method of microwave-assisted quickly synthesis in low temperature nano-silicon nitride-silicon carbide composite powder body | |
| Xing et al. | Mullite rod-enhanced porous SiC ceramics prepared at low temperature from photovoltaic waste | |
| Liu et al. | Recycling photovoltaic silicon waste for fabricating porous mullite ceramics by low-temperature reaction sintering | |
| KR20120133439A (en) | Manufacturing Method of Sintered SiC Regenerative Materials From Silicon Sludge | |
| CN114751730B (en) | Porous mullite ceramic and preparation method thereof | |
| CN102433583A (en) | Preparation method of mullite whiskers | |
| CN113233877A (en) | Sodium removal method for calcining alpha alumina | |
| CN110240483B (en) | Method for preparing silicon carbide porous ceramic by using crystalline silicon waste mortar | |
| CN113234234B (en) | Method for preparing aluminum-based metal-organic framework material by using high-alumina fly ash | |
| CN110092381B (en) | Preparation method of high-purity silicon carbide material | |
| CN112760703A (en) | Method for preparing mullite whisker from dedusting ash of electric melting alpha-beta alumina brick | |
| CN110407241B (en) | Preparation method of high-activity calcium oxide | |
| CN106348773A (en) | Erosion fire-resistant crucible of Lithium electricity resistance material added with SiAlON-AlN-TiN | |
| CN105924170A (en) | Si-SiC substrate material and preparation method thereof | |
| CN114790107B (en) | SiO preparation at low temperature by using polycrystalline silicon cutting waste 2 -Si 3 N 4 Method for compounding ceramic | |
| CN105621468B (en) | A kind of preparation method of high purity aluminium oxide |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |