Composition for chemically activating silico-aluminous materials, chemically activated silico-aluminous materials, and methods of making and using the same

Abstract

The present application relates to the technical field of chemically activated silico-aluminate material, and discloses a composition for chemically activated silico-aluminate material, a chemically activated silico-aluminate material, and a preparation method and application thereof.The composition contains a main agent and an auxiliary agent; the main agent includes a base component, carbon black, and a chemical activator; the base component contains 60-80wt% of slag, 5-20wt% of metakaolin, and 5-20wt% of silica fume, based on the total weight of the base component; the specific surface area of the carbon black is 405-435m 2 / g, and the average particle size is 20-40nm.The chemically activated silico-aluminate material obtained by using the composition for chemically activated silico-aluminate material provided by the present application has excellent mechanical strength and electrical conductivity, and has good application prospects in the fields of building structure health monitoring, traffic state detection, energy conversion and storage, snow melting and deicing, and building heating.

Description

Technical Field

[0001] This invention relates to the field of chemically activated aluminosilicate materials, specifically to compositions for chemically activated aluminosilicate materials, chemically activated aluminosilicate materials, their preparation methods, and applications. Background Technology

[0002] Conductive cement concrete is an advanced functional building material. By adding highly conductive fillers such as carbon fiber, graphene, carbon nanotubes, and carbon black to the matrix material, its electrical properties can be improved, making it more intelligent.

[0003] Currently, cement-based materials are commonly used as the matrix material for conductive cement concrete. However, cement production is an energy-intensive process that is accompanied by the emission of large amounts of dust and harmful gases such as sulfur, carbon, and nitrogen, which imposes a significant burden on the environment.

[0004] Chemically activated aluminosilicate materials are a new type of aluminosilicate inorganic cementitious material. They are made primarily from industrial / agricultural solid waste or natural minerals rich in aluminosilicates. Under the action of strong alkali or strong acid, the activity of the raw materials is activated, resulting in reactions such as dissolution, condensation, and coagulation. After the Si-O and Al-O bonds of the aluminosilicate raw materials break, active aluminate ions and silicate ions are released. These ions are then hydrolyzed (or hydrated) and re-condensed to form dimers or polymers of silicon-oxygen tetrahedra and aluminum-oxygen tetrahedra. They further condense and eventually harden into an amorphous or semi-crystalline inorganic cementitious material.

[0005] Chemically excited silicon-aluminate materials significantly reduce carbon emissions and energy consumption during their preparation process due to their non-firing process and the reuse of industrial waste. In addition, the high alkaline ion content and microporous structure inside chemically excited silicon-aluminate materials give them certain ionic conductivity.

[0006] To enhance the conductivity of chemically excited aluminosilicate materials, conductive materials such as graphite, carbon fiber, and carbon black are typically added during the preparation process.

[0007] CN105218004A discloses a method for preparing a conductive geopolymer, comprising the following steps: 1) mixing graphene, dispersant A and water, grinding and dispersing to obtain a preliminarily dispersed graphene dispersion.

[0008] 2) Mix the alkali metal silicate solution with the graphene dispersion obtained in step 1), stir evenly, add dispersant B, grind and disperse to obtain an alkali-activated solution of graphene dispersion. The modulus of the alkali metal silicate solution is 1-4, and the solid content is 30-60%. 3) Mix the aluminosilicate raw material with granulated blast furnace slag, grind, and obtain the composite geopolymer powder. 4) Mix the composite geopolymer powder obtained in step 3) with the alkali-activated solution of graphene dispersion obtained in step 2), stir evenly, and obtain the conductive geopolymer. This prior art imparts good electrical conductivity to the geopolymer while maintaining its mechanical properties; however, the cost of applying this prior art to large-scale conductive concrete / conductive geopolymer composite engineering is relatively high, and the conductivity still needs to be improved. Summary of the Invention

[0009] The purpose of this invention is to provide a chemically activated aluminosilicate material that simultaneously achieves good electrical and mechanical properties while being inexpensive.

[0010] To achieve the above objectives, a first aspect of the present invention provides a composition for chemically activated aluminosilicate materials, the composition comprising a main agent and an auxiliary agent; said main agent includes a base component, carbon black, and a chemical activator;

[0011] The carbon black content is 0.5-6 parts by weight relative to 100 parts by weight of the base component, and the chemical activator content is 40-50 parts by weight.

[0012] Based on the total weight of the basic components, the basic components contain 60-80 wt% slag, 5-20 wt% metakaolin and 5-20 wt% silica fume.

[0013] The specific surface area of ​​the carbon black is 405-435 m². 2 / g, with an average particle size of 20-40nm;

[0014] The modulus of the chemical activator is <0.8, and the content of alkali metal oxide in the chemical activator is 3-4 wt%, and the solid content is 14-25 wt%.

[0015] A second aspect of the present invention provides a method for preparing a chemically activated silicon-aluminum conductive material, the method comprising using the components of the chemically activated silicon-aluminum material composition described in the first aspect, comprising:

[0016] (1) The components in the main agent and the components in the auxiliary agent are stirred and mixed to obtain a slurry;

[0017] (2) The slurry is cured to obtain the chemically activated aluminosilicate material.

[0018] A third aspect of the present invention provides a chemically activated aluminosilicate material prepared by the method described in the second aspect above.

[0019] The fourth aspect of the present invention provides the application of the chemically activated aluminosilicate material described in the third aspect above in the field of building materials.

[0020] The chemically activated silicon-aluminum material obtained by using the composition for chemically activated silicon-aluminum materials provided by the present invention has the advantages of high conductivity, high strength, low carbon and environmental protection and low cost, realizing the integration of structure and function of chemically activated silicon-aluminum materials.

[0021] The method for preparing chemically excited silicon-aluminum materials provided by this invention is simple to operate and conducive to large-scale production. Detailed Implementation

[0022] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0023] It should be noted that the average particle size in this invention refers to the particle size corresponding to the cumulative particle size distribution fraction of carbon black powder sample reaching 50% when tested using a nanoparticle size analyzer.

[0024] It should be noted that, in this invention, the modulus of the chemical activator is the ratio of the molar amount of SiO2 to the molar amount of the alkali metal oxide in the chemical activator. For example, when the chemical activator is a potassium-based activator (K2O·nSiO2), the modulus of the chemical activator is the ratio of the molar amount of SiO2 to the molar amount of K2O.

[0025] It should be noted that in this invention, iron oxide refers to ferric oxide.

[0026] As previously described, a first aspect of the present invention provides a composition for chemically activated aluminosilicate materials, the composition comprising a main agent and an auxiliary agent; the main agent includes a base component, carbon black, and a chemical activator;

[0027] The carbon black content is 0.5-6 parts by weight relative to 100 parts by weight of the base component, and the chemical activator content is 40-50 parts by weight.

[0028] Based on the total weight of the basic components, the basic components contain 60-80 wt% slag, 5-20 wt% metakaolin and 5-20 wt% silica fume.

[0029] The specific surface area of ​​the carbon black is 405-435 m². 2 / g, with an average particle size of 20-40nm;

[0030] The modulus of the chemical activator is <0.8, and the content of alkali metal oxide in the chemical activator is 3-4 wt%, and the solid content is 14-25 wt%.

[0031] This invention provides exemplary examples to illustrate the meaning of the content of alkali metal oxides in the chemical activator. Exemplarily, when the chemical activator is a sodium-based activator (Na₂O·nSiO₂), the content of alkali metal oxides in the sodium-based activator is the ratio of the mass of Na₂O to the total mass of Na₂O and SiO₂ in the chemical activator; when the chemical activator is a potassium-based activator (K₂O·nSiO₂), the content of alkali metal oxides in the potassium-based activator is the ratio of the mass of K₂O to the total mass of K₂O and SiO₂ in the chemical activator.

[0032] Preferably, the modulus of the chemical activator is 0.6-0.7. This invention has found that, under this preferred condition, the obtained chemically activated aluminosilicate material possesses good flowability and early strength, exhibits excellent mechanical properties within a short curing time, and maintains superior electrical properties even after 28 days of age.

[0033] In a preferred embodiment, the chemical activator is a potassium-based activator.

[0034] According to a preferred embodiment, the potassium-based activator is prepared by a method comprising the following steps:

[0035] Potassium silicate, potassium hydroxide, and water are mixed to obtain a potassium-based activator.

[0036] The present invention does not have any special requirements for the mixing method; it is sufficient to ensure that potassium silicate, potassium hydroxide and water are mixed evenly. Those skilled in the art can choose according to their needs.

[0037] It should be noted that the present invention does not have any particular requirements on the type of water. For example, it can be deionized water or ultrapure water. Those skilled in the art can choose according to their needs. The present invention is described only once in one aspect and is not described repeatedly. Those skilled in the art should not understand this as a limitation of the present invention.

[0038] In a preferred embodiment, the carbon black content is 4-6 parts by weight relative to 100 parts by weight of the base component. The inventors of this invention have discovered that, in this preferred embodiment, the mechanical and electrical properties of the obtained chemically activated aluminosilicate material can maintain a good balance.

[0039] Preferably, based on the total weight of the basic components, the basic components contain 70-80 wt% slag, 5-15 wt% metakaolin, and 5-15 wt% silica fume.

[0040] Preferably, the SiO2 content in the silica fume is ≥96 wt%.

[0041] Preferably, the silica fume has an average particle size of 0.35-21.5 μm and a specific surface area of ​​1.75 × 10⁻⁶. 5 -1.80×10 5 m 2 / g.

[0042] According to a preferred embodiment, the slag contains 30-45 wt% silica, 10-20 wt% alumina, and 35-50 wt% calcium oxide.

[0043] In a preferred embodiment, the metakaolin contains 45-60 wt% silica, 35-50 wt% alumina, and <2 wt% iron oxide.

[0044] Preferably, the additives include dispersants and defoamers;

[0045] The content of the dispersant is 0.01-6 parts by weight relative to 100 parts by weight of the base component, and the content of the defoamer is 0.005-3 parts by weight.

[0046] In a preferred embodiment, the dispersant is selected from at least one of polyvinylpyrrolidone, polyacrylate, polyacrylamide, polyvinylidene fluoride, and sodium dodecylbenzenesulfonate.

[0047] Preferably, the defoamer is selected from at least one of tributyl phosphate, polydimethylsiloxane, polypropylene glycol, and polyoxyethylene.

[0048] As previously described, a second aspect of the present invention provides a method for preparing chemically activated aluminosilicate materials, the method comprising using the components of the chemically activated aluminosilicate material composition described in the first aspect, including:

[0049] (1) The components in the main agent and the components in the auxiliary agent are stirred and mixed to obtain a slurry;

[0050] (2) The slurry is cured to obtain the chemically activated aluminosilicate material.

[0051] According to a preferred embodiment, step (1), the step of stirring and mixing the components in the main agent and the components in the auxiliary agent, includes:

[0052] S1: Carbon black, additives and chemical activators are first stirred and mixed to obtain mixture I;

[0053] S2: The mixture I and the mixture containing the basic components are mixed by a second stirring to obtain a slurry.

[0054] Preferably, in step S1, the conditions for the first stirring and mixing include: a rotation speed of 500-1000 rpm and a time of 20-60 min.

[0055] In a preferred embodiment, in step S2, the conditions for the second stirring and mixing include: a rotation speed of 120-150 rpm and a time of 2-3 min.

[0056] Preferably, in step (2), the conditions for the maintenance treatment include: a temperature of 15-25°C and a humidity of 60-90%.

[0057] According to a preferred embodiment, before the curing treatment, the slurry is first cast into a shape, covered with plastic wrap, and left to stand for 18-30 hours in an environment of 18-22°C and relative humidity ≥90% before the curing treatment is carried out.

[0058] In a preferred embodiment, the curing treatment is carried out in a constant temperature and humidity curing chamber.

[0059] As previously stated, a third aspect of the present invention provides a chemically activated aluminosilicate material prepared by the method described in the second aspect above.

[0060] As previously stated, the fourth aspect of the present invention provides the application of the chemically activated aluminosilicate material described in the third aspect in the field of building materials.

[0061] The present invention will be described in detail below through examples. In the following examples, unless otherwise specified, the raw materials are all commercially available or self-made.

[0062] Potassium silicate: purchased from Shanghai Maclean Biochemical Technology Co., Ltd., grade P850160.

[0063] Slag: The content of silicon dioxide is 32.09 wt%, the content of aluminum oxide is 16.55 wt%, and the content of calcium oxide is 37.65 wt%, purchased from Jiyuan Guotai Micro Powder Technology Co., Ltd.

[0064] Metakaolin: containing 47.19 wt% silica, 49.11 wt% alumina, and 0.79 wt% iron oxide, purchased from Inner Mongolia Chaoneng New Materials Co., Ltd.

[0065] Silica fume: SiO2 content is 97.42 wt%, average particle size is 7.73 μm, and specific surface area is 1.80 × 10⁻⁶. 5 m 2 / g, purchased from Shanghai Tiankai Building Materials Technology Co., Ltd., grade 970 silica powder.

[0066] Carbon black:

[0067] Carbon Black I: Specific surface area is 420 m² 2 / g, with an average particle size of 23-28nm, purchased from Suqian Nakaite New Material Technology Co., Ltd., brand name Super-P.

[0068] Carbon black DI: specific surface area is 120-130m² 2 / g, with an average particle size of 30-45nm, purchased from Jiangsu Xianfeng Nanomaterials Co., Ltd., brand name XFI15.

[0069] Dispersant: Polyvinylpyrrolidone, purchased from Shanghai Maclean Biochemical Technology Co., Ltd., brand name P816205.

[0070] Defoamer: Tributyl phosphate, purchased from Shanghai McLean Biochemical Technology Co., Ltd., brand name T818517.

[0071] The following preparation examples and comparative preparation examples are used to illustrate the preparation of potassium-based activators.

[0072] Preparation Example 1

[0073] Potassium silicate, potassium hydroxide and water are mixed to obtain a potassium-based activator, named Chemical Activator I;

[0074] The specific formula is shown in Table 1.

[0075] Preparation Example 2

[0076] This preparation example was carried out using a method similar to that of Preparation Example 1, except that the formulation was different from that in Preparation Example 1.

[0077] A potassium-based activator was prepared and named Chemical Activator II. The specific formulation is shown in Table 1.

[0078] Comparative Preparation Example 1

[0079] This preparation example was carried out using a method similar to that of Preparation Example 1, except that the formulation was different from that in Preparation Example 1.

[0080] A potassium-based activator was prepared and named chemical activator DI. The specific formulation is shown in Table 1.

[0081] Table 1

[0082] Preparation Example 1 Preparation Example 2 Comparative Preparation Example 1 Potassium silicate / g 3.39 3.95 4.52 potassium hydroxide / g 5.85 5.63 5.42 Deionized water / g 35.71 34.66 33.61 Modulus of potassium-based activator 0.6 0.7 0.8 Alkali metal oxide content of potassium-based activator / wt% 3.39 3.39 3.39 Solid content of potassium-based activator / wt% 20.56 21.65 22.82 Nomenclature of potassium-based activators Chemical activator I Chemical activator II Chemical activator DI

[0083] Example 1

[0084] This embodiment illustrates the preparation of chemically activated aluminosilicate materials by referring to the formulation and process parameters shown in Table 2 and following the steps below:

[0085] (1) The carbon black, additives (dispersant, defoamer) and chemical activator are first stirred and mixed to obtain mixture I;

[0086] (2) The mixture I and the mixture containing the basic components are mixed by a second stirring to obtain a slurry;

[0087] (3) The slurry is cast into a shape, covered with plastic wrap, left to stand in a 20°C environment for 24 hours, and then cured in a constant temperature and humidity curing chamber to obtain the chemically activated silicon-aluminum material.

[0088] Example 2

[0089] This embodiment uses a similar method to Example 1, except that the formulation is different from that in Example 1.

[0090] Chemically excited aluminosilicate materials were prepared, and the specific formulation is shown in Table 2.

[0091] Example 3

[0092] This embodiment uses a method similar to that of Example 1, except that the amount of carbon black is adjusted to 0.5g, the amount of dispersant is adjusted to 0.5g, and the amount of defoamer is adjusted to 0.25g. All other aspects are the same as in Example 1, and chemically activated aluminosilicate material is prepared.

[0093] Comparative Example 1

[0094] This comparative example was conducted using a method similar to that of Example 1, except that the formulation was different from that in Example 1.

[0095] Chemically excited aluminosilicate materials were prepared, and the specific formulation is shown in Table 2.

[0096] Comparative Example 2

[0097] This comparative example was conducted using a method similar to that of Example 1, except that the formulation was different from that in Example 1.

[0098] Chemically excited aluminosilicate materials were prepared, and the specific formulation is shown in Table 2.

[0099] Comparative Example 3

[0100] This embodiment uses a method similar to that of Example 1, except that an equal weight of chemical activator DI is used to replace chemical activator I in Example 1, while the rest is the same as in Example 1, to prepare chemically activated aluminosilicate materials.

[0101] Comparative Example 4

[0102] This comparative example was prepared using a method similar to that of Example 1, except that carbon black DI was used to replace carbon black I in Example 1, while all other aspects were the same as in Example 1, to obtain chemically activated aluminosilicate materials.

[0103] Comparative Example 5

[0104] This comparative example was prepared using a method similar to that of Example 1, except that the amount of carbon black I was adjusted to 10g, the amount of dispersant was adjusted to 10g, and the amount of defoamer was adjusted to 5g. All other aspects were the same as in Example 1, and chemically activated aluminosilicate materials were prepared.

[0105] Table 2

[0106] Example 1 Example 2 Comparative Example 1 Comparative Example 2 Basic components Slag / g 80.0 80.0 60.0 80.0 metakaolin / g 15.0 5.0 30.0 20.0 silica fume / g 5.0 15.0 10.0 0 Carbon black / g type Carbon Black I Same as Example 1 Same as Example 1 Same as Example 1 Dosage / g 6 4 Same as Example 1 Same as Example 1 Chemical activators type Chemical activator I Chemical activator II Same as Example 1 Same as Example 1 Dosage / g 44.95 44.24 Same as Example 1 Same as Example 1 Additives Dispersant / g 6 4 Same as Example 1 Same as Example 1 Defoamer / g 3 2 Same as Example 1 Same as Example 1 First stirring and mixing engine speed / rpm 800 Same as Example 1 Same as Example 1 Same as Example 1 Time / min 40 Same as Example 1 Same as Example 1 Same as Example 1 Second mixing engine speed / rpm 145 Same as Example 1 Same as Example 1 Same as Example 1 Time / min 2 Same as Example 1 Same as Example 1 Same as Example 1 Maintenance and treatment Temperature / °C 20 Same as Example 1 Same as Example 1 Same as Example 1 humidity / % 90 Same as Example 1 Same as Example 1 Same as Example 1

[0107] Test case

[0108] (1) The fluidity of the slurry obtained in step (2) of the above example was tested using the method specified in GB / T 8077-2000;

[0109] (2) The solidification time (including initial solidification time and final solidification time) of the chemically activated aluminosilicate materials prepared in the above examples were tested using the method specified in GB / T 1346-2011.

[0110] (3) The compressive strength (compressive strength after 28 days of curing treatment) of the chemically activated aluminosilicate material prepared in the above example was tested using the method specified in GB / T 17671-2021.

[0111] (4) The AC resistivity of the chemically excited silicon-aluminate material prepared in the above example was tested according to the method in https: / / doi.org / 10.1016 / j.jobe.2022.105022 to evaluate the conductivity of the chemically excited silicon-aluminate material (AC resistivity after 28 days of curing treatment).

[0112] The results of the above performance tests are shown in Table 3.

[0113] Table 3

[0114]

[0115] The results above show that the slurry prepared using the chemically activated aluminosilicate material composition provided by the present invention has good fluidity, and the obtained chemically activated aluminosilicate material has a suitable setting time, maintaining excellent compressive strength and electrical conductivity even after 28 days.

[0116] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A composition for use in chemically activated aluminosilicate materials, characterized in that, The composition contains a main agent and an auxiliary agent; the main agent includes a base component, carbon black, and a chemical activator; The content of carbon black is 4-6 parts by weight relative to 100 parts by weight of the base component, and the content of the chemical activator is 40-50 parts by weight. Based on the total weight of the basic components, the basic components contain 70-80 wt% slag, 5-15 wt% metakaolin and 5-15 wt% silica fume. The specific surface area of ​​the carbon black is 405-435 m². 2 / g, with an average particle size of 20-40nm; The modulus of the chemical activator is <0.8, and the content of alkali metal oxide in the chemical activator is 3-4 wt%, and the solid content is 14-25 wt%.

2. The composition according to claim 1, characterized in that, The modulus of the chemical activator is 0.6-0.

7.

3. The composition according to claim 1 or 2, characterized in that, The SiO2 content in the silica fume is ≥96 wt%; And / or, the silica fume has an average particle size of 0.35-21.5 μm and a specific surface area of ​​1.75 × 10⁻⁶. 5 -1.80×10 5 m 2 / g.

4. The composition according to claim 1 or 2, characterized in that, The slag contains 30-45 wt% silica, 10-20 wt% alumina, and 35-50 wt% calcium oxide. And / or, the metakaolin contains 45-60 wt% silica, 35-50 wt% alumina, and <2 wt% iron oxide.

5. The composition according to claim 1 or 2, characterized in that, The additives include dispersants and defoamers; The content of the dispersant is 0.01-6 parts by weight relative to 100 parts by weight of the base component, and the content of the defoamer is 0.005-3 parts by weight.

6. A method for preparing chemically activated aluminosilicate materials, characterized in that, This method utilizes the components of the chemically activated aluminosilicate material composition according to any one of claims 1-5, comprising: (1) The components in the main agent and the components in the auxiliary agent are stirred and mixed to obtain a slurry; (2) The slurry is cured to obtain the chemically activated aluminosilicate material.

7. The method according to claim 6, characterized in that, In step (1), the step of stirring and mixing the components in the main agent and the components in the auxiliary agent includes: S1: Carbon black, additives and chemical activators are first stirred and mixed to obtain mixture I; S2: The mixture I and the mixture containing the basic components are mixed by a second stirring to obtain a slurry.

8. A chemically activated aluminosilicate material prepared by the method of claim 6 or 7.

9. The application of the chemically activated aluminosilicate material according to claim 8 in the field of building materials.

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