A nano-enzyme carbonized product, a preparation method and application thereof

Abstract

The application provides a nano-enzyme carbonized product, which is obtained by carbonization curing of a carbonized product precursor; the carbonized product precursor comprises: 30-60 parts by weight of solid waste; 20-40 parts by weight of filling material; 1-15 parts by weight of carbonic anhydrase nano-enzyme; 5-15 parts by weight of water reducing agent; and 10-30 parts by weight of water. Compared with the prior art, the carbonic anhydrase nano-enzyme is added to accelerate the absorption of carbon dioxide and the conversion into carbonate in the carbonization curing process, thereby improving the mechanical strength and durability of the product. Meanwhile, the added carbonic anhydrase nano-enzyme can specifically accelerate the absorption of carbon dioxide and the rapid conversion into carbonate through enzymatic action. With the rapid conversion of carbon dioxide, the material continuously absorbs more carbon dioxide, the generated carbonate combines with calcium ions to generate calcium carbonate, which fills the pores of the product and forms an interpenetrating network structure, thereby improving the strength and durability of the product.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of building materials, and particularly relates to a nano-enzyme carbonized product, a preparation method and application thereof. BACKGROUND

[0002] With the rapid development of industrialization, solid waste is increasing year by year. If these solid wastes cannot be comprehensively utilized, it will inevitably cause many hazards to the environment, such as occupying land, polluting the air, wasting resources, etc. One of the most widely and effective ways of solid waste resource utilization is to use it in building materials.

[0003] In recent years, carbonized products have emerged as the times require, which use solid waste as raw material, pass in carbon dioxide for carbonization curing, and obtain products for building boards, floor tiles, etc. However, the problems of low carbonization degree and uneven carbonization of carbonized products limit their application and promotion. In view of this problem, technical personnel began to study different technical schemes to improve the carbonization degree of the product, so as to increase the mechanical strength of the product.

[0004] Many technical personnel add porous materials such as zeolite to promote more carbon dioxide to enter by manufacturing porous structure, so as to improve the carbonization degree. However, this method is only practical and feasible when single-component carbon dioxide gas is passed in for carbonization. With the popularization of industrialization, when multi-component tail gas and waste gas after preliminary treatment are carbonized, in addition to carbon dioxide in the gas atmosphere, there will also be sulfur dioxide, nitrogen and the like. The porous structure not only promotes the entry of carbon dioxide, but also allows sulfur dioxide, nitrogen and the like to enter. These gases will occupy the reaction sites of carbon dioxide, so that even more carbon dioxide enters the inside, but cannot react, thereby reducing the carbonization degree and affecting the mechanical properties of the product as a whole. SUMMARY

[0005] Therefore, the technical problem to be solved by the present application is to provide a nano-enzyme carbonized product with high mechanical strength and durability, a preparation method and application thereof.

[0006] The present application provides a nano-enzyme carbonized product, which is obtained by carbonization curing of a carbonized product precursor.

[0007] The carbonized product precursor comprises:

[0008]

[0009] Preferably, the solid waste is selected from one or more of smelting steel slag, slag, red mud and magnesium slag;

[0010] The filler is selected from one or more of cement, fly ash and quartz sand;

[0011] The water reducing agent is selected from one or more of a naphthalene series high-efficiency water reducing agent, an aliphatic high-efficiency water reducing agent, an amino high-efficiency water reducing agent, and a polycarboxylic acid high-performance water reducing agent.

[0012] Preferably, the carbonic anhydrase nano-enzyme is a zinc-containing metal-organic framework material.

[0013] Preferably, the carbonized product precursor comprises:

[0014]

[0015] The application also provides a preparation method of the above-mentioned nano-enzyme carbonized product, comprising the following steps:

[0016] S1) mixing solid waste, filler, carbonic anhydrase nano-enzyme, water reducing agent, and water to obtain a carbonized product precursor;

[0017] S2) carbonizing and curing the carbonized product precursor to obtain a nano-enzyme carbonized product.

[0018] Preferably, the step S1) specifically comprises:

[0019] mixing the solid waste and the filler to obtain dry mixed materials;

[0020] mixing the carbonic anhydrase nano-enzyme, the water reducing agent, and water, and then introducing a small amount of carbon dioxide to obtain a mixed solution;

[0021] mixing the dry mixed materials and the mixed solution to form a carbonized product precursor.

[0022] Preferably, the amount of carbon dioxide introduced is 0.2-1 mol / L.

[0023] Preferably, the pressure of the carbonizing and curing is 0.1-0.6 MPa; the carbonizing and oxidizing time is 2-72 h; and the volume concentration of carbon dioxide in the carbonizing and oxidizing atmosphere is greater than or equal to 5%.

[0024] Preferably, the atmosphere of the carbonizing and curing is selected from one or more of a thermal power plant tail gas, a cement plant tail gas, a kiln tail gas, an ammonia production device by-product gas, and a hydrogen production device by-product gas.

[0025] The application also provides an application of the above-mentioned nano-enzyme carbonized product as a building material.

[0026] The application provides a nano-enzyme carbonized product, which is obtained after carbonization curing of a carbonized product precursor; the carbonized product precursor comprises: 30-60 parts by weight of solid waste; 20-40 parts by weight of filling material; 1-15 parts by weight of carbonic anhydrase nano-enzyme; 5-15 parts by weight of water reducing agent; and 10-30 parts by weight of water. Compared with the prior art, the carbonic anhydrase nano-enzyme is added to accelerate the absorption of carbon dioxide and the conversion into carbonate in the carbonization curing process, thereby improving the mechanical strength and durability of the product. At the same time, the added carbonic anhydrase nano-enzyme can specifically accelerate the absorption of carbon dioxide and the rapid conversion into carbonate through enzymatic action. With the rapid conversion of carbon dioxide, the material continuously absorbs more carbon dioxide, and the generated carbonate combines with calcium ions to form calcium carbonate, which fills the pores of the product, optimizes the internal structure, forms an interpenetrating network structure, and thus improves the strength and durability of the product. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the embodiments of the application. Obviously, the described embodiments are only a part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the application.

[0028] The application provides a nano-enzyme carbonized product, which is obtained after carbonization curing of a carbonized product precursor;

[0029] The carbonized product precursor comprises:

[0030]

[0031] According to the application, the solid waste can be any solid waste known to those skilled in the art, and there is no special limitation. In the application, one or more of smelting steel slag, furnace slag, red mud and magnesium slag is preferred. In the embodiments provided by the application, the content of the solid waste in the carbonized product precursor is specifically 45 parts by weight, 35 parts by weight, 30 parts by weight, 50 parts by weight or 60 parts by weight.

[0032] According to the application, the filling material is preferably one or more of cement, fly ash and quartz sand; the particle size of the filling material is preferably 50-200 mesh; the content of the filling material in the carbonized product precursor is preferably 20-35 parts by weight, and more preferably 25-30 parts by weight; in the embodiments provided by the application, the content of the filling material in the carbonized product precursor is specifically 25 parts by weight or 30 parts by weight.

[0033] According to the application, the carbonic anhydrase nanozyme is preferably a zinc-containing metal organic framework material (Zn-MOFs); the organic ligand of the zinc-containing metal organic framework material is preferably one or more of 5,5'-bistriazolyl and / or 2-methyl imidazole; the activated ligand is preferably histidine and / or threonine, more preferably histidine and threonine; the molar ratio of the histidine to threonine is preferably (1-5):1, more preferably (2-4):1, and more preferably (1.5-3.5):1, and most preferably 3:1; in the application, the molar ratio of the organic ligand to the activated ligand is preferably 1:(0.5-2), more preferably 1:(0.8-1.5), and more preferably 1:(0.8-1.2), and most preferably 1:1; and it is prepared according to the following steps: A1) mixing a zinc salt with an alcohol solvent to obtain a zinc salt solution; mixing an organic ligand, an activated ligand, and water to obtain a ligand solution; A2) mixing and reacting the zinc salt solution and the ligand solution to obtain a zinc-containing metal organic framework material; the zinc salt is any zinc salt known to those skilled in the art without special limitation, and in the application, zinc nitrate is preferred; the alcohol solvent is any alcohol solvent known to those skilled in the art without special limitation, and in the application, methanol is preferred; the molar ratio of the zinc salt to the alcohol solvent is preferably 1:(5-20), more preferably 1:(8-15), and more preferably 1:10; the molar ratio of the total ligand in the ligand solution to water is preferably 1:(300-800), more preferably 1:(400-600), and more preferably 1:500; the mixing and reaction is preferably carried out under ultrasonic conditions; and after the mixing and reaction, centrifugation, washing, and drying are preferably carried out to obtain the zinc-containing metal organic framework material; the centrifugation is preferably carried out at a speed of 5000-10000 r / min, more preferably 6000-9000 r / min, and more preferably 8000 r / min; the washing is preferably carried out using an alcohol solvent, and more preferably using methanol; after the washing using an alcohol solvent, standing for 4-8 h, and more preferably standing for 6 h, the centrifugation and washing steps are repeated, and finally drying is carried out; the drying is preferably vacuum drying; the drying temperature is preferably 80-100 DEG C; and the content of the carbonic anhydrase nanozyme in the carbonized product precursor is preferably 5-15 parts by weight; in the examples provided in the application, the content of the carbonic anhydrase nanozyme in the carbonized product precursor is specifically 5 parts by weight, 10 parts by weight, or 15 parts by weight. The nanozyme is a kind of simulated enzyme with unique properties of nanomaterials and catalytic function. It has the characteristics of high catalytic efficiency, stability, and specific selection of enzymes, and through the design of its structure and the introduction of functional groups, it can specifically absorb carbon dioxide and can achieve trace adsorption of carbon dioxide. Therefore, even if mixed gas or low carbon dioxide concentration is used during carbonization, it will not affect the absorption and utilization of carbon dioxide during the carbonization process of the product, and the carbonization degree can be improved.In addition, nanozymes can promote carbon mineralization of products, increase the carbon fixation amount, carbonization degree and carbonization uniformity of products, thereby improving the strength and durability of products.

[0034] According to the present invention, the water reducer is preferably one or more of a naphthalene-based high-efficiency water reducer, an aliphatic high-efficiency water reducer, an amino high-efficiency water reducer and a polycarboxylic acid high-performance water reducer; the content of the water reducer in the carbonized product precursor is preferably 8 to 12 parts by weight, more preferably 10 parts by weight.

[0035] According to the present invention, the content of water in the carbonized product precursor is preferably 12 to 30 parts by weight, more preferably 12 to 25 parts by weight, and even more preferably 12 to 20 parts by weight; in the embodiments provided by the present invention, the content of water in the carbonized product precursor is specifically 15 parts by weight, 10 parts by weight, 12 parts by weight or 20 parts by weight.

[0036] The above-mentioned carbonized product precursor is carbonized to obtain a nanozyme carbonized product after carbonization curing; the pressure of the carbonization curing is preferably 0.1-0.6 MPa; the time of the carbonization oxidation is preferably 2-72 hours; the volume concentration of carbon dioxide in the carbonization oxidation atmosphere is preferably greater than or equal to 5%; the carbonization curing atmosphere is selected from one or more of thermal power plant exhaust gas, cement plant exhaust gas, kiln exhaust gas, ammonia production device by-product gas and hydrogen production device by-product gas.

[0037] According to the present invention, the compressive strength of the nanozyme carbonized product is preferably greater than or equal to 55 MPa; the flexural strength of the nanozyme carbonized product is preferably greater than 11 MPa; and the carbon fixation rate of the nanozyme carbonized product is preferably greater than or equal to 22%.

[0038] The present invention adds carbonic anhydrase nanozymes to accelerate the absorption of carbon dioxide and its conversion into carbonate ions during the carbonization curing process, thereby improving the mechanical strength and durability of the product; at the same time, the added carbonic anhydrase nanozymes can specifically accelerate the absorption of carbon dioxide and quickly convert it into carbonate ions through enzymatic action. With the rapid conversion of carbon dioxide, the material will continuously absorb more carbon dioxide, and the generated carbonate ions will combine with calcium ions to form calcium carbonate, which will fill the pores of the product, optimize the internal structure, and form an interpenetrating network structure, thereby improving the strength and durability of the product.

[0039] The present invention also provides a method for preparing the above-mentioned nanozyme carbonized product, comprising the following steps: S1) mixing solid waste, filler, carbonic anhydrase nanozyme, water reducer and water to obtain a carbonized product precursor; S2) carbonizing and curing the carbonized product precursor to obtain a nanozyme carbonized product.

[0040] Wherein, the application has no special restriction on the source of all raw materials, which can be commercially available; the solid waste, filler, carbonic anhydrase nano-enzyme, water-reducing agent and water are the same as described above, which will not be described here.

[0041] The solid waste, filler, carbonic anhydrase nano-enzyme, water-reducing agent and water are mixed to obtain a carbonization product precursor; in the application, this step is preferably specifically as follows: the solid waste and the filler are mixed to obtain dry mixed material; the carbonic anhydrase nano-enzyme, water-reducing agent and water are mixed, and then a small amount of carbon dioxide is introduced to obtain a mixed solution; the dry mixed material and the mixed solution are mixed and formed to obtain the carbonization product precursor. Wherein, the amount of the introduced carbon dioxide is preferably 0.2-1 mol / L; the forming method is a method well known to those skilled in the art, which has no special restriction, and in the application, the carbonization product precursor is formed by introducing into a mold, curing and then demolding; the curing temperature is preferably 20-30℃, more preferably 25℃; the curing time is preferably 12-48h, more preferably 12-36h, and more preferably 12-24h.

[0042] The carbonization product precursor is carbonized and cured to obtain a nano-enzyme carbonization product; the carbonization and curing pressure is preferably 0.1-0.6 MPa, more preferably 0.2-0.6 MPa, more preferably 0.3-0.5 MPa, and most preferably 0.4 MPa; the carbonization and oxidation time is preferably 2-72h, more preferably 12-72h, more preferably 12-60h, more preferably 24-48h, and most preferably 36h; the volume concentration of carbon dioxide in the carbonization and oxidation atmosphere is preferably greater than or equal to 5%; the carbonization and curing atmosphere is selected from one or more of the following: tail gas of a thermal power plant, tail gas of a cement plant, tail gas of a kiln, by-product gas of an ammonia production device and by-product gas of a hydrogen production device.

[0043] The nano-enzyme added in the preparation of the carbonization product in the application is a kind of nano-material, which has chemical inertness and no biological effect, has a wide range of uses, and has important significance for industrial application and promotion. In addition, the nano-enzyme has strong designability, can introduce specific functional groups, selectively absorb carbon dioxide, and can achieve trace adsorption of carbon dioxide. When the mixed flue gas is introduced, the flue gas does not need to be pretreated, and the carbonization reaction is not affected or is slightly affected by the change of the proportion of each gas in the flue gas.

[0044] In order to further illustrate the application, the application of a nano-enzyme carbonization product, its preparation method and application are described in detail in the following embodiments.

[0045] The reagents used in the following examples are commercially available; the red mud used in the examples and comparative examples is sourced from a local factory, and its production process is the Bayer process, and the main chemical component index is SiO2 5%~25%, CaO 2%~10%; the steel slag is sourced from a local steel plant, and the form of calcium element in the material can be dicalcium silicate, tricalcium silicate, and the total content of dicalcium silicate and tricalcium silicate is greater than or equal to 30%; the slag is sourced from a local factory, and the main chemical component index is CaO 20%~30%; the filler is 425 cement; the water reducing agent is a polycarboxylic acid water reducing agent, which is sourced from Yinghe Shenglai Biological Technology Co., Ltd.; the nano-enzyme Cu-MOFs is sourced from XFF45 of Xianfeng Nanometer Material Technology Co., Ltd., and the nano-enzyme Zn-MOFs is sourced from Xianfeng Nanometer Material Technology Co., Ltd., and the organic ligand is 2-methyl imidazole, and the active ligand is histidine and threonine, and the specific preparation method is: 1) dissolve zinc nitrate in methanol, and the molar ratio of zinc nitrate to methanol is 1:10; 2) dissolve 2-methyl imidazole, histidine and threonine in water, and the molar ratio of 2-methyl imidazole to histidine and threonine is 1:1, and the molar ratio of histidine to threonine is 3:1, and the molar ratio of all ligands to water is 1:500; then mix the materials in step 1) and the materials in step 2), and place the mixed solution in an ultrasonic reaction kettle for reaction for 12 h, and then centrifuge it at 8000 r / min, and wash it with methanol, and stand for 6 h, and repeat the centrifugation and washing, and finally vacuum dry at 100°C, and the obtained white powder is Zn-MOFs.

[0046] Examples 1~5 and Comparative Examples 1~2

[0047] The nano-enzyme carbonized product is prepared according to the type and content of the raw materials in Table 1, and the specific steps are as follows:

[0048] Step (1) Mix the solid waste and the filler, and stir uniformly to obtain dry mixed material;

[0049] Step (2) Mix the nano-enzyme, the water reducing agent and water, and then pass 0.5 mol / L carbon dioxide into the mixture to obtain a mixed solution;

[0050] Step (3) Add the mixed solution to the dry mixed material, and stir uniformly to obtain mixed material;

[0051] Step (4) Pour the mixed material into a mold, and cure at 25°C for 12 h, and then demold to obtain a rough blank;

[0052] Step (5) Carbonize the rough blank, and obtain the product; the carbonization atmosphere is 10% carbon dioxide; the carbonization pressure is 0.4 MPa, and the carbonization time is 36 h.

[0053] Table 1 Content of each component in the nano-enzyme carbonized product

[0054]

[0055]

[0056] Unless otherwise specified, the raw materials in this scheme are common materials in the art.

[0057] The performance of the nano-enzyme carbonized products obtained in Examples 1-5 and Comparative Examples 1-2 was detected, and the detection results are shown in Table 2. Among them, the test method of carbon sequestration rate: calculate according to the specific gravity before and after carbonization; the test of compressive strength: determine according to GB / T5072-2008; the test of flexural strength: determine according to GB / T3001-2007.

[0058] Table 2 Performance detection results of nano-enzyme carbonized products

[0059] Serial No. Carbon fixation rate (%) Compressive strength (MPa) Flexural strength (MPa) Example 1 22.0 55 11.3 Example 2 25.2 72 14.2 Example 3 24.6 70 13.6 Example 4 28.0 78 16 Example 5 23.1 65 13.2 Comparative Example 1 22.6 53 11.6 Comparative Example 2 20.1 48 11.0

Claims

1. A nano-enzyme carbonized article, characterized in that, obtained by carbonization curing of the carbonized product precursor; the carbonized product precursor comprises: solid waste 30-60 parts by weight; filler 20-40 parts by weight; carbonic anhydrase nanoenzyme 1-15 parts by weight; water reducing agent 5-15 parts by weight; water 10-30 parts by weight; the carbonic anhydrase nanoenzyme is a zinc-containing metal organic framework material; the organic ligand of the zinc-containing metal organic framework material is one or more of 5,5'-bisbenzotriazole and / or 2-methylimidazole; the activating ligand is histidine and threonine; the molar ratio of histidine to threonine is (1-5):

1.

2. The nanoenzymatic carbonization article of claim 1, wherein, the solid waste is selected from one or more of smelting steel slag, slag, red mud and magnesium slag; the filler is selected from one or more of cement, fly ash and quartz sand; the water reducing agent is selected from one or more of naphthalene-based high-efficiency water reducing agent, aliphatic high-efficiency water reducing agent, amino high-efficiency water reducing agent and polycarboxylic acid high-performance water reducing agent.

3. The nanoenzymatic carbonization article of claim 1, wherein, the carbonized product precursor comprises: solid waste 30-60 parts by weight; filler 25-30 parts by weight; carbonic anhydrase nanoenzyme 5-15 parts by weight; water reducing agent 5-15 parts by weight; water 10-20 parts by weight.

4. A method of preparing the nano-enzyme carbonized preparation of claim 1, characterized in that, comprising the following steps: S1) mixing solid waste, filler, carbonic anhydrase nanoenzyme, water reducing agent and water to obtain a carbonized product precursor; S2) carbonization curing of the carbonized product precursor to obtain a nanoenzyme carbonized product.

5. The production method according to claim 4, characterized by, the step S1) is specifically: mixing solid waste and filler to obtain dry mixing material; mixing carbonic anhydrase nanoenzyme, water reducing agent and water, and then introducing a small amount of carbon dioxide to obtain a mixed solution; mixing the dry mixing material and the mixed solution to form a carbonized product precursor.

6. The production method according to claim 5, wherein The amount of carbon dioxide introduced is 0.2-1 mol / L.

7. The preparation method according to claim 4, characterized in that The pressure of the carbonization curing is 0.1-0.6 MPa; the carbonization oxidation time is 2-72 h; the volume concentration of carbon dioxide in the carbonization oxidation atmosphere is greater than or equal to 5%.

8. The preparation method according to claim 4, characterized in that The atmosphere of the carbonization curing is selected from one or more of thermal power plant tail gas, cement plant tail gas, kiln tail gas, ammonia production device by-product gas and hydrogen production device by-product gas.

9. The nanoenzyme carbonized product of any one of claims 1-3 or prepared by the preparation method of any one of claims 4-8 as a building material.

Images