CN118125459A - Silicon-aluminum composite aerogel material with controllable structure and preparation method thereof - Google Patents
Silicon-aluminum composite aerogel material with controllable structure and preparation method thereof Download PDFInfo
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- 239000004964 aerogel Substances 0.000 title claims abstract description 45
- CSDREXVUYHZDNP-UHFFFAOYSA-N alumanylidynesilicon Chemical compound [Al].[Si] CSDREXVUYHZDNP-UHFFFAOYSA-N 0.000 title claims abstract description 28
- 239000002131 composite material Substances 0.000 title claims abstract description 26
- 239000000463 material Substances 0.000 title claims abstract description 25
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 98
- 239000010881 fly ash Substances 0.000 claims abstract description 57
- 238000000034 method Methods 0.000 claims abstract description 23
- 239000011324 bead Substances 0.000 claims abstract description 19
- 238000007667 floating Methods 0.000 claims abstract description 19
- 239000002019 doping agent Substances 0.000 claims abstract description 18
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 claims abstract description 12
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 35
- 235000019441 ethanol Nutrition 0.000 claims description 34
- 239000011259 mixed solution Substances 0.000 claims description 30
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 18
- 238000001035 drying Methods 0.000 claims description 18
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 14
- 238000003756 stirring Methods 0.000 claims description 14
- 239000008367 deionised water Substances 0.000 claims description 13
- 229910021641 deionized water Inorganic materials 0.000 claims description 13
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims description 12
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 12
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 claims description 12
- 239000003960 organic solvent Substances 0.000 claims description 10
- 238000002791 soaking Methods 0.000 claims description 9
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 8
- 238000000227 grinding Methods 0.000 claims description 8
- 238000007873 sieving Methods 0.000 claims description 8
- GOOHAUXETOMSMM-UHFFFAOYSA-N Propylene oxide Chemical compound CC1CO1 GOOHAUXETOMSMM-UHFFFAOYSA-N 0.000 claims description 7
- 238000001914 filtration Methods 0.000 claims description 7
- 239000000126 substance Substances 0.000 claims description 7
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 6
- ZHNUHDYFZUAESO-UHFFFAOYSA-N Formamide Chemical compound NC=O ZHNUHDYFZUAESO-UHFFFAOYSA-N 0.000 claims description 6
- OMOVVBIIQSXZSZ-UHFFFAOYSA-N [6-(4-acetyloxy-5,9a-dimethyl-2,7-dioxo-4,5a,6,9-tetrahydro-3h-pyrano[3,4-b]oxepin-5-yl)-5-formyloxy-3-(furan-3-yl)-3a-methyl-7-methylidene-1a,2,3,4,5,6-hexahydroindeno[1,7a-b]oxiren-4-yl] 2-hydroxy-3-methylpentanoate Chemical compound CC12C(OC(=O)C(O)C(C)CC)C(OC=O)C(C3(C)C(CC(=O)OC4(C)COC(=O)CC43)OC(C)=O)C(=C)C32OC3CC1C=1C=COC=1 OMOVVBIIQSXZSZ-UHFFFAOYSA-N 0.000 claims description 6
- DKGAVHZHDRPRBM-UHFFFAOYSA-N Tert-Butanol Chemical compound CC(C)(C)O DKGAVHZHDRPRBM-UHFFFAOYSA-N 0.000 claims description 5
- 239000000725 suspension Substances 0.000 claims description 5
- 238000004108 freeze drying Methods 0.000 claims description 4
- 239000002202 Polyethylene glycol Substances 0.000 claims description 3
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 claims description 3
- 229920001223 polyethylene glycol Polymers 0.000 claims description 3
- LFQCEHFDDXELDD-UHFFFAOYSA-N tetramethyl orthosilicate Chemical compound CO[Si](OC)(OC)OC LFQCEHFDDXELDD-UHFFFAOYSA-N 0.000 claims description 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 238000000967 suction filtration Methods 0.000 claims description 2
- 238000005406 washing Methods 0.000 claims description 2
- 230000001476 alcoholic effect Effects 0.000 claims 1
- 239000002994 raw material Substances 0.000 abstract description 13
- 229910052710 silicon Inorganic materials 0.000 abstract description 5
- 239000010703 silicon Substances 0.000 abstract description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 abstract description 4
- 230000007547 defect Effects 0.000 abstract description 4
- 238000003980 solgel method Methods 0.000 abstract description 4
- 229910018557 Si O Inorganic materials 0.000 abstract description 3
- 230000001105 regulatory effect Effects 0.000 abstract description 3
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Inorganic materials [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 abstract description 3
- 239000002904 solvent Substances 0.000 abstract description 3
- 229910018125 Al-Si Inorganic materials 0.000 abstract description 2
- 229910018520 Al—Si Inorganic materials 0.000 abstract description 2
- 238000007796 conventional method Methods 0.000 abstract description 2
- 238000009776 industrial production Methods 0.000 abstract 1
- 239000010883 coal ash Substances 0.000 description 16
- 230000000052 comparative effect Effects 0.000 description 8
- 239000000243 solution Substances 0.000 description 8
- 238000002386 leaching Methods 0.000 description 6
- 239000011148 porous material Substances 0.000 description 5
- 238000009413 insulation Methods 0.000 description 4
- 230000007935 neutral effect Effects 0.000 description 4
- 238000001179 sorption measurement Methods 0.000 description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 239000003513 alkali Substances 0.000 description 3
- 239000003054 catalyst Substances 0.000 description 3
- 239000003245 coal Substances 0.000 description 3
- 239000000084 colloidal system Substances 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- -1 silicate ester Chemical class 0.000 description 2
- 239000004965 Silica aerogel Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000002612 dispersion medium Substances 0.000 description 1
- 238000012377 drug delivery Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000013618 particulate matter Substances 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 238000004321 preservation Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 239000011343 solid material Substances 0.000 description 1
- 239000002910 solid waste Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/20—Silicates
- C01B33/26—Aluminium-containing silicates, i.e. silico-aluminates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
- B01J13/0091—Preparation of aerogels, e.g. xerogels
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/12—Surface area
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/16—Pore diameter
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Dispersion Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Silicon Compounds (AREA)
Abstract
The invention discloses a silicon-aluminum composite aerogel material with a controllable structure and a preparation method thereof, and belongs to the technical field of aerogel materials. The silicon-aluminum composite aerogel material is prepared from fly ash floating beads and silicate containing a Si-O structure serving as raw materials, ethanol serving as a solvent and a specific doping agent serving as auxiliary materials through a doped sol-gel method. The obtained silicon-aluminum composite aerogel material has the advantages of good mechanical hardness, high porosity, low density and large specific surface area. Compared with the conventional method which takes the fly ash as the raw material independently and directly, the method not only greatly improves the content and the utilization rate of silicon and aluminum in the raw material, but also overcomes the defect that the proportion of Al-Si in the raw material cannot be effectively regulated when the fly ash is taken as the raw material independently, and can realize fine regulation and control on the structure and the performance of the silicon and aluminum composite aerogel. The preparation process of the silicon-aluminum composite aerogel material is relatively simple, has low cost, can realize industrial production, and widens the research thought for the resource utilization of the fly ash.
Description
Technical Field
The invention belongs to the technical field of aerogel materials, and particularly relates to a silicon-aluminum composite aerogel material with a controllable structure and a preparation method thereof.
Background
Combustion is the most direct way to obtain energy in coal, however, during coal combustion, a large amount of fly ash is produced, wherein fly ash discharged by thermal power generation has become the largest pollution source of industrial solid waste. If the fly ash is improperly treated, numerous damages are caused to the environment and human health, for example, the amount of the fly ash generated by coal burning is relatively large, and a large amount of land is occupied in the storage process; particulate matter formed by fly ash in the atmosphere can promote the formation of haze; the heavy metal and other pollutants contained in the fly ash can enter and pollute the soil along with the rainwater leaching process. Therefore, the comprehensive utilization research of the fly ash is very necessary.
The main chemical components of the fly ash are SiO 2 and Al 2O3 (accounting for about 50% -90% of the total amount), and in order to utilize the effective components, some researchers prepare the fly ash into silica aerogel, alumina aerogel or silicon-aluminum composite aerogel. Aerogel is a highly dispersed solid material in which colloidal particles coalesce with each other to form a nanoporous network structure and the pores are filled with a gaseous dispersion medium. Because of the unique characteristics of ultra-low density, ultra-large specific surface area, ultra-low heat conductivity, ultra-strong adsorption performance, ultra-strong heat insulation performance and the like, the catalyst is widely applied to the fields of heat preservation, heat insulation, adsorption separation, catalytic carrier and the like. The requirements for aerogel structures for different fields of application are also different: in the field of thermal insulation, the structure of aerogel needs to have a high pore structure and low thermal conductivity to provide excellent thermal insulation properties; in the field of adsorption materials, the structure of aerogel is required to have a large specific surface area and uniform pore distribution so as to improve adsorption performance; in the field of catalyst supports, the structure of aerogels needs to have a high pore structure and a large specific surface area to improve the activity and stability of the catalyst; in the biomedical field, the structure of aerogel is required to have good biocompatibility and controllable pore structure for drug delivery, tissue engineering and other applications.
Chinese patents CN101717214A and CN107998996A disclose a method for preparing silicon-aluminum composite aerogel by taking fly ash as a raw material, but because the proportion of Al 2O3 and SiO 2 in the fly ash is fixed, fine control on the structure of the silicon-aluminum composite aerogel cannot be realized, so that the obtained silicon-aluminum composite aerogel has smaller specific surface area, larger aperture and unstable structural performance, and cannot meet the diversified requirements of different fields on the structure of the aerogel; chinese patent CN110668452a discloses a method for preparing a silicon-aluminum composite aerogel from fly ash, which adopts an alkali fusion-acid leaching process to extract silicon-aluminum components in the fly ash, and adopts a sol-gel method to synthesize the silicon-aluminum composite aerogel, however, the technology has the defects of low silicon-aluminum utilization rate, high raw material cost and the like; chinese patent CN116354373A adopts a two-step leaching method of alkali fusion, water leaching and acid leaching to prepare silicon-aluminum composite aerogel from fly ash, and the method improves the total utilization rate of silicon-aluminum elements, but has more complicated steps.
Disclosure of Invention
The invention aims to provide a silicon-aluminum composite aerogel material with a controllable structure and a preparation method thereof, so as to overcome the defects that the silicon-aluminum utilization rate is low, the steps are complicated, the structure performance of the silicon-aluminum composite aerogel is unstable and fine control cannot be realized when the silicon-aluminum composite aerogel is prepared from fly ash in the prior art.
The technical scheme adopted by the invention is as follows:
the preparation method of the silicon-aluminum composite aerogel with controllable structure comprises the following steps:
(1) Grinding and sieving the fly ash, pouring the fly ash into deionized water, centrifuging, carrying out suction filtration and drying to obtain fly ash floating beads; the fly ash is the fly ash containing more than 20 percent of Al 2O3 by mass and more than 35 percent of SiO 2 by mass;
(2) Soaking the fly ash floating beads in hydrochloric acid for 4-8 hours to obtain sol, filtering the sol and washing the sol with deionized water to neutrality;
(3) Placing the washed sol into a mixed solution of ethanol and water, stirring and dissolving the sol, and adding a doping agent into the sol to obtain gel;
(4) Soaking the gel in a mixed solution of silicate and absolute ethyl alcohol under the water bath condition of 40-80 ℃, and replacing the mixed solution of silicate and ethyl alcohol for 3-5 times every 8-12 hours;
(5) And (3) replacing the soaked gel with an alcohol organic solvent, and drying the aerogel material.
Further, the specific process of the step (1) is as follows: grinding the fly ash, sieving with a 100-150 mesh sieve, pouring into deionized water, stirring uniformly, putting into a centrifuge, centrifuging for 5-10 minutes at a rotation speed of 5000-8000 rpm, taking the suspension at the upper layer, filtering, and drying at 80-110 ℃ for 8-12 hours to obtain the fly ash floating beads.
Further, the concentration of the hydrochloric acid in the step (2) is 1-4 mol/L, and each time of soaking, the soaking is carried out according to the proportion that 20-100 mL of hydrochloric acid is added into each 1g of fly ash floating beads.
Further, in the mixed solution of ethanol and water in the step (3), the volume ratio of ethanol to water is 1 (1-4), and the volume ratio of gel to the mixed solution of ethanol and water is 1:2-10 when soaking each time.
Further, the dopant in the step (3) is a mixture of a substance a and a substance B, wherein the substance a is propylene oxide or butylene oxide, and the substance B is at least one of formamide, N-dimethylformamide or polyethylene glycol.
Further, the addition amount of the doping agent in the step (3) is 30-37 times of the mass of the fly ash floating beads, wherein the mass ratio of the substance A to the substance B is 1: (1.6-2.5).
Further, in the mixed solution of silicate and absolute ethyl alcohol in the step (4), the volume ratio of silicate to absolute ethyl alcohol is (1-5): 100, wherein the silicate is at least one of methyl orthosilicate or ethyl orthosilicate.
Further, in the soaking in the step (4), the volume ratio of the gel to the mixed solution of silicate and ethanol is 1:2-10.
Further, the alcohol organic solvent in the step (5) is at least one of methanol, ethanol, isopropanol, acetone or tertiary butanol.
Further, the specific process of solvent replacement in the step (5) is as follows: soaking the gel soaked in the step (4) in an alcohol organic solvent, and replacing the alcohol organic solvent for three times every 8-12 hours.
Further, the drying in the step (5) is freeze drying or normal pressure drying, wherein the freeze drying is that gel subjected to alcohol organic solvent replacement is dried for 24-36 hours at the temperature of-70 to-40 ℃; and the normal pressure drying is to dry the gel after the replacement of the alcohol organic solvent at 50-70 ℃ for 24-36 h.
The invention also provides the silicon-aluminum composite aerogel material with the controllable structure, which is prepared by the method.
The invention has the beneficial effects that:
The invention takes fly ash floating beads and silicate ester containing Si-O structure as raw materials, ethanol as solvent and specific doping agent as auxiliary materials, and prepares the silicon-aluminum composite aerogel material with controllable structure by doping sol-gel method. The obtained silicon-aluminum composite aerogel material has the advantages of good mechanical hardness, high porosity, low density and large specific surface area. Compared with the conventional method which directly takes the fly ash as the raw material alone, the method firstly prepares the fly ash into the fly ash floating beads, avoids the loss of silicon and aluminum in the processes of alkali melting, acid leaching and the like, and greatly improves the content and the utilization rate of the silicon and aluminum in the raw material; and then the fly ash floating beads and silicate ester containing Si-O structure are matched to serve as raw materials, and the silicon source content is regulated in the sol-gel process, so that the defect that the Al-Si proportion in the raw materials cannot be effectively regulated when the fly ash is independently used as the raw materials is overcome, and the fine regulation and control on the structure and the performance of the silicon-aluminum composite aerogel are realized. In addition, the addition of the specific dopant not only shortens the reaction flow time by 6-8 hours, but also can further regulate and control the uniformity and mechanical strength of the aperture of the silicon-aluminum composite aerogel by adjusting the dosage of the dopant so as to meet the diversified demands of different fields on the aerogel structure.
The aerogel material has the advantages of relatively simple preparation process and low cost, can be industrially produced, and widens the research ideas for the resource utilization of the fly ash.
Detailed Description
The invention is further described below with reference to examples, which are not to be construed as limiting the scope of the invention, but rather as falling within the scope of the invention, since numerous insubstantial modifications and adaptations of the invention will now occur to those skilled in the art in light of the foregoing disclosure.
Example 1
Grinding coal ash of a coal-fired unit, sieving the coal ash with a 100-mesh sieve, and determining that the mass percentage of Al 2O3 and SiO 2 in the coal ash is 20% and 35% respectively, wherein the coal ash source is a 4# unit of a three-river power plant in Hebei province.
Pouring the sieved fly ash into deionized water, stirring, putting into a centrifuge, centrifuging for 5 minutes at a rotation speed of 5000rpm after stirring uniformly, taking the suspension at the upper layer, filtering, and drying at 80 ℃ for 12 hours to obtain the fly ash floating beads.
1G of the floating beads are soaked in 20-100ml of 1mol/L hydrochloric acid for 4 hours to obtain sol, and the sol is filtered and washed to be neutral by deionized water. Stirring and dissolving the washed sol into a mixed solution of ethanol and water, wherein the ratio of the ethanol to the water in the mixed solution is 1:2, then 10g of propylene oxide and 20g of formamide were added thereto as dopants to obtain a gel. The gel was immersed in a mixed solution of 5mL of methyl orthosilicate and 100mL of absolute ethanol at a water bath temperature of 60℃and the ethyl orthosilicate/ethanol solution was replaced three times every 12 hours. And (3) replacing the soaked gel with tertiary butanol, replacing tertiary butanol once every 12 hours for three times, and drying the colloid at 60 ℃ under normal pressure for 32 hours to obtain the fly ash aerogel material.
Example 2
Grinding coal ash of a coal-fired unit, sieving the coal ash with a 150-mesh sieve, and determining that the mass percentage of Al 2O3 and SiO 2 in the coal ash is 35% and 45% respectively, wherein the coal ash is from a 1# unit of a Hebei Sanhe power plant.
Pouring the sieved fly ash into deionized water, stirring, putting into a centrifuge, centrifuging for 5 minutes at a rotational speed of 8000 revolutions per minute after stirring uniformly, taking the suspension at the upper layer, filtering, and drying at 80 ℃ for 12 hours to obtain the fly ash floating beads.
1G of the floating beads are soaked in 20-100ml of 4mol/L hydrochloric acid for 4 hours to obtain sol, and the sol is filtered and washed to be neutral by deionized water. Stirring and dissolving the washed sol into a mixed solution of ethanol and water, wherein the ratio of the ethanol to the water in the mixed solution is 1:4, then 12g of butylene oxide and 25g of polyethylene glycol were added thereto as dopants to obtain a gel. The gel was immersed in a mixed solution of 1mL of ethyl orthosilicate and 100mL of absolute ethanol at a water bath temperature of 60℃and the ethyl orthosilicate/ethanol solution was replaced three times every 12 hours. And (3) replacing the soaked gel with methanol, replacing the methanol every 8 hours for three times, and drying the colloid at the temperature of-70 ℃ for 24 hours to obtain the fly ash aerogel material.
Example 3
Grinding coal ash of a coal-fired unit, sieving the coal ash with a 100-mesh sieve, and determining that the mass percentage of Al 2O3 and SiO 2 in the coal ash is 35% and 40% respectively, wherein the coal ash source is a 2# unit of a three-river power plant in Hebei province.
Pouring the sieved fly ash into deionized water, stirring, putting into a centrifuge, centrifuging for 10 minutes at a rotation speed of 5000 rpm after stirring uniformly, taking the suspension at the upper layer, filtering, and drying at 110 ℃ for 8 hours to obtain the fly ash floating beads.
1G of the floating beads are soaked in 20-100ml of 2mol/L hydrochloric acid for 4 hours to obtain sol, and the sol is filtered and washed to be neutral by deionized water. Stirring and dissolving the washed sol into a mixed solution of ethanol and water, wherein the ratio of the ethanol to the water in the mixed solution is 1:1, then 10g of propylene oxide and 25g of N, N-dimethylformamide were added thereto as dopants to obtain a gel. The gel was immersed in a mixed solution of 2mL of ethyl orthosilicate and 100mL of absolute ethanol at a water bath temperature of 60c, and the ethyl orthosilicate/ethanol solution was replaced three times every 12 hours. And replacing the soaked gel with isopropanol, replacing the isopropanol every 12 hours for three times, and freeze-drying the gel at-40 ℃ for 36 hours to obtain the fly ash aerogel material.
Example 4
The preparation method was the same as in example 3, except that after the gel was obtained, the mixed solution in which the gel was immersed was a mixed solution prepared from 5mL of ethyl orthosilicate and 100mL of absolute ethanol.
Example 5
The preparation method is the same as in example 3, except that the drying is performed by adopting a normal pressure drying mode.
Comparative example 1
Grinding coal ash of a coal-fired unit, sieving the coal ash with a 100-mesh sieve, and determining that the mass percentage of Al 2O3 and SiO 2 in the coal ash is 35% and 40% respectively, wherein the coal ash source is a 2# unit of a three-river power plant in Hebei province.
1G of the fly ash is soaked in 20-100ml of 2mol/L hydrochloric acid for 4 hours to obtain sol, and the sol is filtered and washed to be neutral by deionized water. Stirring and dissolving the washed sol into a mixed solution of ethanol and water, wherein the ratio of the ethanol to the water in the mixed solution is 1:1, then 12g of propylene oxide and 25g of N, N-dimethylformamide were added thereto as dopants to obtain a gel. The gel was immersed in a mixed solution of 2mL of ethyl orthosilicate and 100mL of absolute ethanol at a water bath temperature of 60c, and the ethyl orthosilicate/ethanol solution was replaced three times every 12 hours. And replacing the soaked gel with isopropanol, replacing the isopropanol every 12 hours for three times, and drying the gel at the temperature of minus 40 ℃ for 36 hours to obtain the fly ash aerogel material.
Comparative example 2
The preparation method was the same as in example 3, except that after the gel was obtained, the solution in which the gel was immersed was 100mL of an absolute ethanol solution.
Comparative example 3
The preparation method was the same as in example 3, except that after the gel was obtained, the mixed solution in which the gel was immersed was a mixed solution prepared from 0.5mL of ethyl orthosilicate and 100mL of absolute ethanol.
Comparative example 4
The preparation method was the same as in example 3, except that after the gel was obtained, the mixed solution in which the gel was immersed was a mixed solution prepared from 10mL of ethyl orthosilicate and 100mL of absolute ethanol.
Comparative example 5
The preparation was carried out as in example 3, except that 6g of propylene oxide and 18g of N, N-dimethylformamide were used as dopants.
Comparative example 6
The preparation method is the same as in example 3, except that no dopant is added.
Comparative example 7
The preparation was the same as in example 3, except that only 10g of propylene oxide was added as dopant.
Comparative example 8
The preparation was the same as in example 3, except that only 25g of N, N-dimethylformamide was added as dopant.
Table 1 Performance parameters of the fly ash aerogel materials prepared in various examples
The above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and those skilled in the art may modify or substitute the technical solution of the present invention, and the scope of the present invention is defined by the claims.
Claims (10)
1. The preparation method of the silicon-aluminum composite aerogel with the controllable structure is characterized by comprising the following steps of:
(1) Grinding and sieving the fly ash, pouring the fly ash into deionized water, centrifuging, carrying out suction filtration and drying to obtain fly ash floating beads; the fly ash is the fly ash containing more than 20 percent of Al 2O3 by mass and more than 35 percent of SiO 2 by mass;
(2) Soaking the fly ash floating beads in hydrochloric acid for 4-8 hours to obtain sol, filtering the sol and washing the sol with deionized water to neutrality;
(3) Placing the washed sol into a mixed solution of ethanol and water, stirring and dissolving the sol, and adding a doping agent into the sol to obtain gel;
(4) Soaking the gel in a mixed solution of silicate and absolute ethyl alcohol under the water bath condition of 40-80 ℃, and replacing the mixed solution of silicate and ethyl alcohol for 3-5 times every 8-12 hours;
(5) And (3) replacing the soaked gel with an alcohol organic solvent, and drying the aerogel material.
2. The method according to claim 1, wherein the specific process of step (1) is: grinding the fly ash, sieving with a 100-150 mesh sieve, pouring into deionized water, stirring uniformly, putting into a centrifuge, centrifuging for 5-10 minutes at a rotation speed of 5000-8000 rpm, taking the suspension at the upper layer, filtering, and drying at 80-110 ℃ for 8-12 hours to obtain the fly ash floating beads.
3. The method according to claim 1, wherein the concentration of hydrochloric acid in the step (2) is1 to 4mol/L.
4. The method according to claim 1, wherein the volume ratio of ethanol to water in the mixed solution of ethanol and water in the step (3) is1 (1-4).
5. The method of claim 1, wherein the dopant of step (3) is a mixture of a substance a and a substance B, wherein substance a is propylene oxide or butylene oxide and substance B is at least one of formamide, N-dimethylformamide or polyethylene glycol.
6. The method according to claim 1, wherein the dopant is added in the amount of 30-37 times the mass of the fly ash floating beads in the step (3), wherein the mass ratio of the substance A to the substance B is 1: (1.6-2.5).
7. The method according to claim 1, wherein in the mixed solution of silicate and absolute ethanol in the step (4), the volume ratio of silicate to absolute ethanol is (1-5): 100, wherein the silicate is at least one of methyl orthosilicate or ethyl orthosilicate.
8. The method of claim 1, wherein the alcoholic organic solvent of step (5) is at least one of methanol, ethanol, isopropanol, acetone, or t-butanol.
9. The method according to claim 1, wherein the freeze drying is to replace the gel with an alcohol organic solvent, and the gel is dried for 24-36 hours at-70 to-40 ℃; and the normal pressure drying is to dry the gel after the replacement of the alcohol organic solvent at 50-70 ℃ for 24-36 h.
10. A structurally controllable silica-alumina composite aerogel material prepared by the method of any one of claims 1 to 9.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101717214A (en) * | 2009-11-26 | 2010-06-02 | 西南科技大学 | Method for preparing silicon-aluminum aerogel by using fly ash as raw material through normal pressure drying |
| CN104591193A (en) * | 2014-12-29 | 2015-05-06 | 中国神华能源股份有限公司 | Method for preparing Al2O3-SiO2 aerogel |
| CN109621849A (en) * | 2019-01-25 | 2019-04-16 | 浙江工业大学 | A kind of atmospheric preparation method of coated with silica alumina composite aeroge |
| CN112456961A (en) * | 2020-11-27 | 2021-03-09 | 南京龙宇光电材料科技有限公司 | Composite aerogel heat insulation material and preparation method and application thereof |
| WO2023239952A1 (en) * | 2022-06-10 | 2023-12-14 | Aspen Aerogels, Inc. | Aluminosilicate aerogels |
-
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- 2024-03-18 CN CN202410304389.2A patent/CN118125459A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101717214A (en) * | 2009-11-26 | 2010-06-02 | 西南科技大学 | Method for preparing silicon-aluminum aerogel by using fly ash as raw material through normal pressure drying |
| CN104591193A (en) * | 2014-12-29 | 2015-05-06 | 中国神华能源股份有限公司 | Method for preparing Al2O3-SiO2 aerogel |
| CN109621849A (en) * | 2019-01-25 | 2019-04-16 | 浙江工业大学 | A kind of atmospheric preparation method of coated with silica alumina composite aeroge |
| CN112456961A (en) * | 2020-11-27 | 2021-03-09 | 南京龙宇光电材料科技有限公司 | Composite aerogel heat insulation material and preparation method and application thereof |
| WO2023239952A1 (en) * | 2022-06-10 | 2023-12-14 | Aspen Aerogels, Inc. | Aluminosilicate aerogels |
Non-Patent Citations (1)
| Title |
|---|
| 马志斌等: ""循环流化床粉煤灰理化特性及元素溶出行为研究进展"", 《循环流化床粉煤灰理化特性及元素溶出行为研究进展》, vol. 40, no. 6, 30 June 2021 (2021-06-30), pages 3058 - 3071 * |
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