Method for manufacturing CO2 immobilized materials and CO2 immobilized compounds

Abstract

The present invention relates to a CO2 immobilizing material containing one or more non-hydraulic compounds selected from the group consisting of γ-2CaO·SiO2, 3CaO·2SiO2, α-CaO·SiO2, and magnesium calcium silicate, wherein the CO2 immobilizing material contains Li and the content of the Li is 0.001 to 1.0% by mass in terms of oxides, and a method for manufacturing a CO2 immobilized product by carbonation treatment of the above-mentioned CO2 immobilizing material at 75°C or below and / or 50%RH or above.

Description

Methods for manufacturing CO2 immobilization materials and CO2 immobilized compounds This invention relates to CO 2. Immobilized chemicals and CO 2. Method for manufacturing immobilized materials. As a measure to reduce greenhouse gas emissions, CO is removed during manufacturing. 2. Concrete products obtained by forced absorption or carbonation (hereinafter referred to as CO2) 2. Absorbent concrete has been partially put into practical use. It is a type of CO2 recovery and storage technology, specifically CCUS (Carbon dioxide Capture, Utilization and Storage). 2. Absorbent concrete was also mentioned in the "Carbon Cycle Technology Roadmap" published by Japan's Ministry of Economy, Trade and Industry in 2019, and technology development for its popularization and expansion is currently underway. Patent document 1 discloses the use of CO2 during concrete manufacturing. 2. A method for forced absorption or carbonation. Specifically, a method for immobilizing carbon dioxide is disclosed, comprising: a contact step in which a gas containing carbon dioxide contacts a cementitious hardened material, and immobilizes the carbon dioxide contained in the gas into the cementitious hardened material. [Prior Art Documents] [Patent Documents] [Patent Document 1] Japanese Patent Application Publication No. 2020-15659 [The problem that the invention aims to solve] However, the immobilization method in Patent Document 1 sets the water content in the carbon dioxide-containing gas to 1.5% or more and the temperature to 75-175°C, but does not disclose or teach how to immobilize CO2. 2. To fix the material. In summary, the purpose of this invention is to provide a method for removing CO2 through carbonation. 2. Immobilized CO 2. Immobilized chemicals and CO 2. Manufacturing method of immobilized compounds. [Means of problem-solving] As a result of dedicated research in order to solve the aforementioned problems, the inventors of this case conceived of the following invention and discovered that it can solve these problems. That is, the invention is as follows. [1] A CO 2. Immobilized chemical materials containing selected γ-2CaO·SiO 2,3CaO・2SiO 2. α-CaO·SiO 2. One or more non-hydraulic compounds from the group consisting of magnesium calcium silicate, wherein the CO 2. The immobilized material contains Li, and the content of Li, converted to oxides, is 0.001~1.0% by mass. [2] A CO 2. Immobilized chemical materials containing selected γ-2CaO·SiO 2,3CaO・2SiO 2. α-CaO·SiO 2. One or more non-hydraulic compounds and disaccharides in the group consisting of magnesium calcium silicate. [3] CO such as [1] or [2] 2. Immobilized chemical materials, wherein the CaO / SiO in the non-hydraulic compound 2. Molar ratio 0.8~2.3. [4] CO as in [1] 2. Immobilized materials, which also contain disaccharides. [5] Such as CO from any of [1], [2], [4]. 2. Immobilized chemical materials, wherein, relative to the CO 2. 100 parts by weight of the immobilized chemical material contains 0.5 to 10 parts by weight of the disaccharide. [6] CO as in any of [1], [2], [4], [5] 2. Immobilized material, wherein the disaccharide comprises trehalose. [7] A CO 2. The method for manufacturing the immobilized compound is to carry out CO at a temperature below 75°C and / or above 50%RH, as described in any one of [1] to [6]. 2. Carbonation treatment of immobilized chemical materials. [Effects of the invention] According to the present invention, it is possible to provide a method for removing CO by carbonation treatment. 2. Immobilized CO 2. Immobilized chemicals and CO 2. Method for manufacturing immobilized materials. [CO] 2. Immobilized Chemical Material] CO according to an embodiment of the present invention Regarding fixed chemical materials, examples include: First, CO 2. Immobilized chemical materials and second CO 2. Fixation of chemical materials. <First CO> 2. Fixed Chemicals > First CO 2. Immobilized chemical materials containing selected γ-2CaO·SiO 2,3CaO・2SiO 2. α-CaO·SiO 2. And one or more non-hydraulic compounds from the group consisting of magnesium calcium silicate. First CO 2. Immobilized chemical materials, in this CO 2. The fixed chemical contains Li, and its content, converted to oxides, is 0.001~1.0%. It is speculated that through this fixed amount of Li, the carbonation of CSH (calcium silicate hydrate) will promote the formation of a type of hexagonal calcite (Vaterite) of calcium carbonate, and it is believed that a denser hardened state can be easily obtained through carbonation (salt) curing. Here, it is set to "CO" 2. The presence of Li in the immobilized material refers to the presence of Li in CO. 2. The non-hydraulic compounds in the fixed chemical materials contain Li in terms of chemical composition. 2O (its presence can be confirmed using ICP emission spectroscopy), but Li cannot be identified by X-ray diffraction. 2O (Li cannot be observed) The state of 2O (with a clearly defined peak) refers only to the state where the non-hydraulic compound and the Li compound are not physically mixed. This state can be obtained by mixing the respective raw materials and performing heat treatment at a high temperature of 1,000°C or higher. The following is an explanation of each component. (γ-2CaO・SiO 2) γ-2CaO・SiO 2 refers to 2CaO·SiO Among the compounds represented by 2, those known to be in the low-temperature phase, and those that are in the high-temperature phase, α-2CaO·SiO2. 2. α'-2CaO·SiO 2. β-2CaO·SiO 2 are completely different. These are all based on 2CaO·SiO 2 indicates that they are different in crystal structure and density. (3CaO・2SiO 2) 3CaO・2SiO 2 refers to pseudo-argyrite, a mineral containing CaO, also known as rankinite. It is a non-hydratable and chemically stable mineral. 2. It has a significant immobilization effect. (α-CaO・SiO 2) α-CaO・SiO 2 (α-type Wollastonite) refers to wollastonite formed in CaO·SiO₂. Among the compounds represented by 2, those known to be high-temperature phases and those that are low-temperature phases, β-CaO·SiO2... 2 are completely different. These all use CaO and SiO₂. 2 indicates that they are different in crystal structure and density. Naturally occurring wollastonite is a low-temperature phase of β-CaO·SiO2. 2. β-CaO・SiO 2 has needle-like crystals and has been used as an inorganic fibrous material such as wollastonite fiber, but does not have α-CaO·SiO as in this embodiment. 2-class CO 2. Immobilization effect. (Magnesium calcium silicate) Magnesium calcium silicate refers to the general term CaO-MgO-SiO2. The compound is a 2-series compound, but in this embodiment it is preferably 3CaO・MgO・2SiO 2(C 3MS 2) Merwinite, a type of cristobalite, can achieve high CO₂ levels. 2. Immobilization effect. The aforementioned non-hydraulic compound can be one or more types. The Li content in the non-hydraulic compound (or its total content if there are multiple types) should be 0.001-1.0% (calculated as oxides), preferably 0.005-1.0%, more preferably 0.010-0.90%, and even more preferably 0.015-0.80%. If the Li content (calculated as oxides) is less than 0.001%, the carbonation-promoting effect cannot be obtained. If it exceeds 1.0%, the cost will increase. The Li content (calculated as oxides) can be determined using the method described in the examples. Among the aforementioned non-hydraulic compounds, especially γ-2CaO·SiO 2. During manufacturing, a pulverization phenomenon called dusting occurs, therefore the energy required for pulverization is less than that for other compounds. In the long run, CO... 2. The immobilization effect is significant, therefore it is ideal. This embodiment of the non-hydraulic compound can be achieved by combining CaO raw material and SiO2. 2. The raw materials, MgO and Li, are mixed in a predetermined molar ratio and then subjected to heat treatment to obtain the product. Examples of CaO raw materials include: calcium carbonate (such as limestone), calcium hydroxide (such as slaked lime), slaked lime (a byproduct of acetylene), fine powder from waste concrete blocks, concrete sludge (dehydrated blocks) from ready-mixed concrete plants and concrete product plants, incineration ash (fly ash, wood biomass, municipal solid waste incineration ash, sewage sludge incineration ash, etc.), and molten steel slag (converter slag, electric furnace slag, etc.). 2. Raw materials, for example, include silica, clay, and various silica-based dusts generated as industrial byproducts such as silica fume and fly ash. MgO raw materials, for example, include magnesium hydroxide, basic calcium carbonate, and dolomite. Additionally, Li raw materials, for example, include lithium carbonate. Furthermore, CaO raw materials, SiO... 2. If the raw material, MgO, contains Li, there is no need to add additional Li. This is to reduce CO emissions from non-energy sources during heat treatment. 2. For discharge volume, one or more of the following industrial by-products containing CaO can be utilized: quicklime, fine powder generated from waste concrete blocks, concrete sludge, municipal solid waste incineration ash, and sewage sludge incineration ash. Among these, using quicklime, a by-product with less impurities than other industrial by-products, is more ideal. Examples of byproduct slaked lime include: slaked lime produced as a byproduct in the acetylene gas production process using the calcium carbide method (which can be wet or dry depending on the acetylene gas production method); and acetylene byproduct slaked lime contained in the dust captured during the wet dust collection process in a calcium carbide electric furnace. For example, slaked lime typically contains 65-95% calcium hydroxide (preferably 70-90%), 1-10% calcium carbonate, and 0.1-6.0% (preferably 0.1-3.0%) iron oxide. These ratios can be determined using the mass loss (Ca(OH)₂) obtained by X-ray fluorescence spectrometry and differential calorimetric analysis (TG-DTA). 2: Around 405℃~515℃, CaCO3 3: Confirmed at around 650℃~765℃. The volume average particle size determined by laser diffraction / scattering method is approximately 50~100μm. Furthermore, according to JIS K 0068 "Method for Determination of Moisture Content in Chemical Products", the moisture content determined by the loss on drying method should be less than 10%. In addition, it may also contain CaS, Al... 2S 3 and CaC 2. Sulfur compounds such as CaS should preferably be below 2%. As mentioned earlier, there are no particular restrictions on heat treatment at temperatures above 1,000°C, and it can be carried out using methods such as rotary kilns and electric furnaces. The temperature of this heat treatment is not fixed, but it is usually carried out in the range of about 1,000 to 1,800°C, and often in the range of about 1,200 to 1,600°C. This embodiment may also use industrial byproducts containing the non-hydraulic compounds described above. In this case, they will coexist with impurities. Examples of such industrial byproducts include steelmaking slag. CaO raw materials, SiO 2. Raw materials, such as MgO, may sometimes contain impurities, but this is not a particular problem as long as it does not hinder the effectiveness of the present invention. Specific examples of impurities include, for instance, Al. 2O 3. Fe 2O 3. TiO 2. MnO, Na 2O, K 2O, S, P 2O 5. F, B 2O 3. Chlorine, etc. Other coexisting compounds include: free calcium oxide, calcium hydroxide, calcium aluminate, calcium aluminosilicate, calcium ferrite, calcium aluminoferrite, calcium phosphate, calcium borate, magnesium silicate, and leucite (K). 2O, Na 2O)・Al 2O 3・SiO 2. Spinel MgO・Al 2O 3. Magnetite Fe 3O 4. The aforementioned CaS and Al 2S 3. and CaC 2・Sulfur compounds such as CaS, etc. Among these impurities, the content of sulfur (S) in non-hydraulic compounds is highest in oxides (SO₄). 3) The conversion should ideally be below 1.0%, more preferably below 0.7%, and even more preferably below 0.5%. By keeping it below 1.0%, sufficient carbonation (salting) promotion effect can be obtained. Furthermore, the setting of solidification and hardening properties can be kept within an appropriate range. Oxides (SO₄) 3) The converted sulfur content can be determined by fluorescence X-ray diffraction. In addition, sulfur (sulfur) in non-hydraulic compounds can also be present if converted to oxides at approximately 2%. In the immobilized material of the present invention, the content of non-hydraulic compounds (the content in the total amount when multiple compounds are present) is preferably 65% ​​or more, more preferably 70% or more, and even more preferably 75% or more. Additionally, γ-2CaO·SiO2 can also be mixed in. Water hardness other than 2CaO·SiO 2. The maximum mixing ratio is 35%. γ-2CaO·SiO in non-hydraulic compounds The content of γ-2CaO·SiO2 should preferably be above 35%, and more preferably above 45%. In addition, γ-2CaO·SiO2... There is no particular upper limit to the content of γ-2CaO·SiO2. In steelmaking slag, γ-2CaO·SiO2 is preferred. 2. High content of electric furnace reduction slag or stainless steel slag. CaO / SiO in non-hydraulic compounds The molar ratio should ideally be 0.8–2.3, with 1.2–2.3 being more suitable. A molar ratio of 0.8–2.3 can further promote carbonation. Furthermore, from the viewpoint that its effects are more easily manifested in the immobilized material of the present invention, in terms of chemical composition, in CO 2. The fixed chemical material should preferably contain 0.001~1.0 parts of Li per 100 parts. 2O, 45-70 parts CaO, 30-55 parts SiO 2. 0-10 parts of Al 2O 3. Li The content of 2O can be determined by the method described in the examples below. In addition, CaO and SiO... 2. Al 2O 3. It can be determined using fluorescence X-rays. In terms of chemical composition, in CO... 2. It is preferable that 0.002 to 0.5 parts of Li are present in 100 parts of the fixed chemical material. 20, 60-70 parts CaO, 30-45 parts SiO 2. 0.5 to 5 parts Al 2O 3. Furthermore, in terms of chemical composition, CO... 2. In 100 parts of the immobilized chemical material, Li 2O, CaO, SiO 2 and Al 2O The total of 3 should ideally be 90 or more, preferably 95 to 100. Methods for quantifying the non-hydraulic compounds in the immobilized chemical material of the present invention can be exemplified by the Rietveld method, which is performed by powder X-ray diffraction. CO 2. The moisture content of the fixed chemical material, in order to adequately maintain contact between the surface of the non-hydraulic compound and the carbon dioxide-containing gas, should preferably be below 10% by mass, and more preferably 0.01~10% by mass. The CO2... 2. The moisture content of the fixed chemical material can be obtained from the difference between the mass of the sample before drying and the mass after drying at 105°C. Furthermore, CO... 2. The moisture content of the fixed chemical material can be adjusted by heating and drying it at 105°C, adding an appropriate amount of water, and stirring. CO 2. The average particle size of the immobilized chemical material should preferably be 1~100μm, more preferably 1~70μm. An average particle size of 1~70μm promotes the dissolution of water from the particle surface by Ca and facilitates the carbonation reaction. The average particle size can be determined using a laser diffraction / scattering particle size distribution measuring device. In addition, CO 2. Immobilized materials (especially, using γ-2CaO·SiO) The optimal Blaine surface area (at 2°C) is 1,000–10,000 cm². 2 / g, preferably 2,500~10,000cm 2 / g. Based on a specific surface area of ​​2,500~10,000 cm² 2 / g, the contact area between the particles and the water on the particle surface increases and promotes the dissolution of Ca, thereby promoting the carbonation reaction. The specific surface area can be determined by measuring the Blanche air permeation apparatus as described in JIS R 5201. Because it forms chelates with the calcium in the water already dissolved on the particle surface, promoting further dissolution, CO... 2. Immobilized materials should contain more disaccharides such as trehalose, maltose, and sucrose. Among them, trehalose, which has a high promoting effect on carbonation reaction, is particularly suitable. From the perspective of promoting the carbonation reaction, it is preferable to contain 0.5 to 10 parts by mass of disaccharides per 100 parts by mass of non-hydraulic compounds, and more preferably 5 to 10 parts by mass. Furthermore, to obtain a sufficient carbonation-promoting effect, the content of trehalose in the disaccharides should preferably be 90% by mass or more, and more preferably 95% by mass or more. Here, CO The immobilization of material 2 refers to the carbonation of the material and the CO2 content. 2 will form carbonate compounds with the material. Here, the carbonation rate can be expressed as CO. 2. The CaO content in the immobilized material relative to the theoretically immobilized CO The form of the ratio of 2 is obtained in the following manner. Equation (1): Carbonation rate = (ΔM × 56.08) / (M × w) CaO ×44.01) Here, ΔM: the increase in mass [g] due to carbonation, and M: the CO before carbonation. 2. Mass of fixed chemical materials [g], w CaO CO before carbonation 2. CaO in the immobilized material [wt%] In the above formula, the increase in mass due to carbonation refers to the mass of the sample after carbonation minus the sample weight before carbonation. CO2 before carbonation 2. The CaO content in immobilized materials can be determined by fluorescence X-ray analysis. <Second CO 2. Fixed chemical materials > Second CO 2. Immobilized chemical materials containing selected γ-2CaO·SiO 2,3CaO・2SiO 2. α-CaO·SiO 2. One or more non-hydraulic compounds and disaccharides in the group consisting of magnesium calcium silicate. Disaccharides such as trehalose, maltose, and sucrose, because they react with substances already dissolved in CO2... 2. The water and calcium on the surface of the immobilized chemical particles form chelates, further promoting dissolution and thus enhancing the carbonation reaction. From the perspective of further enhancing the carbonation reaction, it is advisable to include trehalose. As mentioned above, the second CO 2. Immobilized materials contain disaccharides, even if such as the first CO... 2. Immobilized materials are generally in CO 2. Even if the immobilized material does not contain a predetermined amount of Li, CO can still be removed through carbonation. 2. Immobilization. In addition, the second CO 2. When immobilized materials must contain non-hydraulic compounds and disaccharides, the first CO2 can be appropriately used. 2. The composition and ideal state of fixed chemical materials. [CO] 2. Method for manufacturing immobilized compounds] The CO of the present invention 2. The method for manufacturing the immobilized compound involves carrying out CO2 production at temperatures below 75°C and / or above 50% RH. 2. Methods for carbonation treatment of immobilized chemical materials. There are no particular limitations on the carbonation treatment method. For example, a method can be used to treat the material by appropriately heating and / or humidifying (adding water) in a gaseous environment containing carbon dioxide at a temperature below 75°C and / or above 50%RH. The optimal temperature for carbonation treatment is 5~75℃, with 5~50℃ being more suitable. Furthermore, the optimal relative humidity is 50~100%RH, with 90~100%RH being more suitable. The aforementioned carbon dioxide-containing gases may include exhaust gases from cement plants and coal-fired power plants, as well as exhaust gases from painting plants. The carbon dioxide content in the gas should preferably be 5% by volume or higher, preferably 10% by volume or higher, and more preferably 15% by volume or higher. The carbon dioxide-containing gas may also contain moisture (water vapor). CO produced by the above methods 2. Immobilized materials, for example, can be used as cement additives, or directly as aggregates in mortar and concrete, roadbed materials, embankment materials, backfill materials, etc. That is, it can effectively fix atmospheric carbon dioxide into CO2. 2. The fixed chemical material can also be further effectively utilized as a concrete material. [Example] The present invention is illustrated in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples as long as it does not depart from its spirit. Additionally, CO 2. Immobilized materials are sometimes simply referred to as "immobilized materials". [Experimental Example 1] CO was produced using the following method. 2. Fixed chemical materials A~F. CO 2. Immobilized chemical A: γ-2CaO·SiO 2. Mix grade 1 calcium carbonate and grade 1 silicon dioxide at a molar ratio of 2:1, and mix grade 1 lithium carbonate with the mixture to ensure that the Li content is based on the oxide (Li... 2O) was converted to 0.1% (containing proportional substitution), and heat-treated at 1,400°C for 2 hours, then left to stand until room temperature to prepare a Blanquer specific surface area system of 4,000 cm². 2 / g of CO 2. Fixation of chemical material A. CO 2. Fixed chemical material B: 3CaO・2SiO 2. Mix grade 1 calcium carbonate and grade 1 silicon dioxide at a molar ratio of 3:2, and mix grade 1 lithium carbonate with the mixture to ensure that the Li content is based on the oxide (Li... 2O) was converted to 0.1% (containing proportional substitution), and heat-treated at 1,400°C for 2 hours, then left to stand until room temperature to prepare a Blanquer specific surface area system of 4,000 cm². 2 / g of CO 2. Fixation of chemical material B. CO 2. Immobilized chemical C: α-CaO・SiO 2. Mix grade 1 calcium carbonate and grade 1 silicon dioxide in a 1:1 molar ratio, and mix grade 1 lithium carbonate with the mixture to ensure that the Li content is based on the oxide (Li... 2O) was converted to 0.1% (containing proportional substitution), and heat-treated at 1,500°C for 2 hours, then left to stand until room temperature to prepare a Blanquer specific surface area system of 4,000 cm². 2 / g of CO 2. Fixation of chemical material C. CO 2. Fixed chemical material D: 3CaO・MgO・2SiO 2. Mix grade 1 calcium carbonate, grade 1 magnesium oxide, and grade 1 silicon dioxide in a molar ratio of 3:1:2, and then mix grade 1 lithium carbonate with the mixture to ensure that the Li content is based on the oxide (Li... 2O) was converted to 0.1% (containing proportional substitution), and heat-treated at 1,400°C for 2 hours, then left to stand until room temperature to prepare a Blanquer specific surface area system of 4,000 cm². 2 / g of CO 2. Fixation of chemical material D. CO 2. Immobilized chemical E: γ-2CaO・SiO 2. Mix grade 1 calcium carbonate and grade 1 silicon dioxide at a molar ratio of 2:1, heat-treat at 1,400°C for 2 hours, and allow to stand until room temperature to prepare a Blanquer specific surface area of ​​4,000 cm². 2 / g of γ-2CaO・SiO 2. CO 2. Immobilized chemical material F:Li 2O+γ-2CaO・SiO 2. Mix grade 1 calcium carbonate and grade 1 silicon dioxide at a molar ratio of 2:1, heat-treat at 1,400°C for 2 hours, and allow to stand until room temperature to prepare a Blanquer specific surface area of ​​4,000 cm². 2 / g of γ-2CaO・SiO 2. Furthermore, grade 1 lithium carbonate was heat-treated at 1,400°C for 2 hours, then allowed to stand until room temperature to prepare Li. 2O powder. For γ-2CaO·SiO 2. Mix Li in the specified proportion 2O powder (obtained by heat-treating grade 1 lithium carbonate at 1,400°C for 2 hours), to make Li 2O becomes 0.1% (internal proportion substitution), producing CO. 2. Immobilized chemical material F. Additionally, each CO 2. The Li content, converted from oxides in the immobilized material, was determined using an ICP emission spectrometer (VISTA-PRO, manufactured by Hitachi Advanced Technology Co., Ltd.). Furthermore, the Li content was confirmed to be the same as the amount added by using an absolute calibration curve method with SPEX XSTC-22 ICP diluted with a mixture. The measurement conditions were as follows: ・Li measurement wavelength: 670.783 nm ・BG correction: Curve fitting ・Standard solution for calibration curve: diluted SPEX XSTC-22 ICP mixture Calibration range: 0-5 mg / L (5 calibration curves: 0 mg / L, 0.1 mg / L, 0.5 mg / L, 1 mg / L, 5 mg / L) ・Quantification using the absolute calibration curve method Fill each plastic cup with 25g of CO. 2. Fix chemical materials A~F and carbonate them in a constant temperature and humidity chamber at 20℃, 80%RH, and 20% by volume of carbon dioxide. After carbonation for each predetermined period shown in Table 1, the mass of the sample after 24 hours at 105℃ was measured, and the carbonation rate was calculated from the mass change before and after carbonation using the formula (1) described above. The results are shown in Table 1. [Table 1] [Experimental Example 2] In Experiment 1, CO 2. In the preparation of immobilized materials A and C, for the mixture of reagent grade 1 lithium carbonate, the content of Li is such that the oxide content (Li) is... 2O) is converted to 0.0005%, 0.002%, 0.006%, 0.1%, 0.15%, 0.8%, 0.9%, 1.0%, and 1.1% (each with its own internal proportion of substitution). In addition, it is compared with the CO in Experiment 1. 2. CO was produced using the same method as the immobilization of chemical A and immobilization of chemical C. 2. Fixed chemical materials A-1~A-7, CO 2. Fixed chemical materials C-1~C-7. For each CO... 2. The immobilized material was evaluated in the same manner as in Experiment 1. The results are shown in Table 2. [Table 2] [Experimental Example 3] CO was prepared in the following manner. 2. Immobilized chemical G~I. CO 2. Immobilized Chemical G: Calcium carbonate (Reagent 1) and silicon dioxide (Reagent 1) are mixed according to the ratio of CaO / SiO₂. 2 molar ratios of 1.2 were mixed, and the mixture was further mixed with reagent grade 1 lithium carbonate to make the Li content in oxides (Li 2O) was converted to 0.1% (containing proportional substitution), and heat-treated at 1,400°C for 2 hours, then left to stand until room temperature to prepare a Blanquer specific surface area system of 4,000 cm². 2 / g of CO 2. Fixation of chemical material G. CO 2. Immobilized Chemical H: Grade 1 calcium carbonate and Grade 1 silicon dioxide were mixed according to the CaO / SiO ratio. 2 molar ratios of 1.8 were mixed, and the mixture was further mixed with reagent grade 1 lithium carbonate to make the Li content in oxides (Li 2O) was converted to 0.1% (containing proportional substitution), and heat-treated at 1,400°C for 2 hours, then left to stand until room temperature to prepare a Blanquer specific surface area system of 4,000 cm². 2 / g of CO 2. Fixation of chemical material H. CO 2. Immobilized Chemical I: Calcium carbonate (Reagent 1) and silicon dioxide (Reagent 1) were mixed according to the CaO / SiO ratio. Mix 2 moles of lithium carbonate at a ratio of 2.3, and mix the mixture with reagent grade 1 lithium carbonate to make the Li content in oxides (Li 2O) was converted to 0.1% (containing proportional substitution), and heat-treated at 1,400°C for 2 hours, then left to stand until room temperature to prepare a Blanquer specific surface area system of 4,000 cm². 2 / g of CO 2. Immobilized chemical material I. CO derived from production 2. Powder X-ray diffraction was performed on the immobilized materials. The results were analyzed using quantitative software to determine the mineral composition. The powder X-ray diffraction apparatus used was the Rigaku SmartLab fully automated multi-object X-ray diffraction system, and the quantitative software used was the Rigaku SmartlabStudio II. Calculate the CO values ​​produced in the same manner as in Experimental Example 1. 2. Carbonation rate of the fixed chemical material. The results are shown in Table 3. [Table 3] [Experimental Example 4] For CO 2. Various additives were added and mixed to a fixed mass of 100 parts of chemical A to achieve the predetermined ratios shown in Table 3. Otherwise, carbonation was carried out in the same manner as in Experimental Example 1, and the carbonation rate was calculated. The results are shown in Table 4. [Table 4] [Experimental Example 5] Using CO For example 2, the carbonation of chemical material A in a constant temperature and humidity chamber was changed from 20°C and 80%RH to the conditions shown in Table 5. Otherwise, the carbonation was carried out in the same manner as in Example 1, and the carbonation rate was calculated. The results are shown in Table 5. [Table 5] Based on the results in Table 1, it is known that the CO of this invention... 2. Immobilized materials will result in a high carbonation rate. According to the results in Table 2, the Li content is primarily determined by the oxide content (Li...). A high carbonation rate can be obtained when the concentration of CaO is converted to 0.001~1.0% by mass. According to the results in Table 3, it is known that due to the CaO / SiO content... A molar ratio of 1.0 to 2.3 yields a good carbonation rate. According to Table 4, the addition of disaccharides significantly enhances carbonation, especially trehalose. Table 5 shows that setting the carbonation temperature below 75°C and / or above 50% RH results in a good carbonation rate. [Experimental Example 6] For CO 2. Various additives were added and mixed to a fixed mass of 100 parts E to achieve the predetermined ratios shown in Table 6. Carbonation was then performed in the same manner as in Experimental Example 1, and the carbonation rate was calculated. The results are shown in Table 6. [Table 6] According to the results in Table 6, the addition of disaccharides significantly enhances carbonation. The effect is even greater with the addition of trehalose. [Industrial Applicability] By using the CO of the present invention 2. When the immobilized chemical material is carbonated at a set temperature below 75℃ and / or a humidity above 50%RH, CO2 can be generated. 2. Immobilization. In addition, CO2... 2. CO obtained by carbonation of immobilized chemical materials 2. The immobilized material can be used in the civil engineering and construction fields as a cement additive, or directly as an aggregate for mortar and concrete, a roadbed material, an embankment material, a backfill material, etc.

Claims

1. A CO2 immobilization material containing one or more non-hydraulic compounds selected from the group consisting of 3CaO・2SiO2, α-CaO・SiO2, and 3CaO・MgO・2SiO2, wherein the CO2 immobilization material contains Li, and the content of Li, converted in oxide form, is 0.001 to 1.0% by mass. "The CO2 immobilization material contains Li" means that the non-hydraulic compounds in the CO2 immobilization material contain Li2O in terms of chemical composition, which can be confirmed by ICP emission spectroscopy analysis; however, X-ray diffraction measurement cannot identify the state of Li2O, that is, it is impossible to observe a clear peak of Li2O. "The CO2 immobilization material contains Li" means that the non-hydraulic compounds and the Li compounds are not in a physically mixed state.

2. A CO2 immobilization material comprising one or more non-hydraulic compounds selected from the group consisting of γ-2CaO・SiO2, 3CaO・2SiO2, α-CaO・SiO2, and 3CaO・MgO・2SiO2, and a disaccharide, wherein 0.5 to 10 parts by mass of the disaccharide are contained relative to 100 parts by mass of the non-hydraulic compound, and the disaccharide comprises trehalose.

3. As in request item 1 or 2, the CO2 immobilization material, wherein, The CaO / SiO2 molar ratio in this non-hydraulic compound is 0.8 to 2.

3.

4. The CO2 immobilization material in Request 1 contains disaccharides.

5. As in request item 4, the CO2 immobilization material, wherein, The CO2 immobilizing agent contains 0.5 to 10 parts by weight of the disaccharide per 100 parts by weight.

6. As in request item 4, the CO2 immobilization material, wherein, This disaccharide contains trehalose.

7. A method for manufacturing a CO2 immobilized material, comprising carbonation treatment of the CO2 immobilized material as claimed in any one of claims 1 to 6 at a temperature below 75°C and / or above 50%RH.