Carbon dioxide trapping composite particle and preparation method thereof

Abstract

Provided are a carbon dioxide trapping composite particle that facilitates carbon neutralization by mineralizing carbon dioxide immobilized in seawater or an aqueous solution in which calcium ions are dissolved, and a method for preparing the same. More specifically, provided are carbon dioxide trapping composite particles that trap carbon dioxide in seawater to form calcium carbonate particles, preferably aragonite-type calcium carbonate, and a method for preparing the same. In one exemplary embodiment, a method of preparing a carbon dioxide trapping composite particle includes: providing a method of immersing a polyamidoamine particle in seawater or an aqueous solution in which calcium ions are dissolved, and maintaining the solution at room temperature at atmospheric pressure to prepare a carbon dioxide trapping composite particle, wherein aragonite-type calcium carbonate particles are formed on the surfaces of the polyamidoamine particles.

Description

Technical Field

[0001] The present invention relates to carbon dioxide capture composite particles and methods for preparing the carbon dioxide capture composite particles, which fix carbon dioxide in seawater or an aqueous solution in which calcium ions are dissolved by mineralization, and the carbon dioxide capture composite particles contribute to carbon neutralization. More specifically, the present invention relates to carbon dioxide capture composite particles, which capture carbon dioxide in seawater to form calcium carbonate particles, preferably aragonite calcium carbonate, and methods for preparing the carbon dioxide capture composite particles. Background Art

[0002] The consumption of petrochemicals in modern society leads to large amounts of carbon emissions in the atmosphere, and the generated carbon dioxide contributes to the global climate crisis. To address this problem, technological advances to effectively capture the generated carbon dioxide and efforts to reduce the production and consumption of petrochemicals are necessary.

[0003] Conventionally, aqueous monoethanolamine (MEA) solutions are used to adsorb carbon dioxide, but they have disadvantages such as corrosion of equipment when using aqueous solutions, the appearance of toxic vapors, and the need for high temperatures when reforming the adsorbed carbon dioxide. In addition, attempts have been made to use inorganic substances such as zeolites, adsorbents containing polyethyleneimine (PEI), porous carbon, metal organic framework compounds (MOFs), etc. to adsorb carbon dioxide gas, but they are greatly affected by moisture and temperature in the air, and require high pressure or high temperature for effective adsorption. It is known that among the known adsorbents at the 186 mg / g level, MOF / GO-U3 has the highest carbon dioxide adsorption efficiency.

[0004] However, no technology has been developed to absorb and remove carbon dioxide from water.

[0005] [Related technical literature] [Patent Document] Korean Patent Publication No. 10-2022-0063429 (May 17, 2022) Summary of the invention [Technical issues] The inventors of the present invention conducted research to provide carbon dioxide capture composite particles and a preparation method thereof that are safer and easier to use than conventionally known carbon dioxide absorbers and can further improve carbon dioxide capture efficiency. As a result, a new concept of carbon dioxide capture particles was developed, thereby completing the present invention.

[0006] The object of the present invention is to provide a carbon dioxide capture composite particle and a preparation method thereof, wherein the carbon dioxide capture composite particle captures carbon dioxide in a particle form and naturally undergoes CaCO3 mineralization in seawater, thereby requiring no artificial additional energy input or separate experimental equipment.

[0007] Another object of the present invention is to provide a method for preparing a large amount of aragonite calcium carbonate using seawater without requiring a separate device or process.

[0008] [Technical solution] In one general aspect, a method for preparing carbon dioxide capture composite particles comprises: immersing polyamidoamine particles in seawater or an aqueous solution in which calcium ions are dissolved, and maintaining the solution at room temperature under normal pressure to prepare carbon dioxide capture composite particles, wherein calcium carbonate particles are formed on the surface of the polyamidoamine particles.

[0009] In one exemplary embodiment, the calcium carbonate particles may be aragonite calcium carbonate particles.

[0010] In another general aspect, a carbon dioxide capture composite particle is provided wherein calcium carbonate particles are formed on the surface of polyamidoamine particles.

[0011] In one exemplary embodiment, in the carbon dioxide capture composite particles, aragonite calcium carbonate particles meet each other and grow on the surface of the polyamidoamine particles.

[0012] In an exemplary embodiment, the carbon dioxide capture composite particles may have a carbon dioxide fixation efficiency of 50 mg-CO2 / g-polymer or higher, more preferably 200 mg-CO2 / g-polymer or higher.

[0013] [Beneficial Effects] Since the carbon dioxide capture composite particles according to an exemplary embodiment of the present invention are in the form of particles, they do not cause corrosion, are easy to use, do not require a separate device or process, and are mineralized only by immersing and maintaining the particles in seawater or an aqueous solution in which calcium ions are dissolved to form aragonite-type calcium carbonate on the surface. In this process, carbon dioxide is captured, and the carbon dioxide fixation efficiency at this time is 60 mg-CO2 / g-polymer or higher, more preferably 200 mg-CO2 / g-polymer or higher, so that an effect equal to or better than that of conventionally known carbon dioxide absorbents can be achieved.

[0014] In addition, the carbon dioxide capture composite particles according to the present invention do not require separate equipment or process conditions, such as high temperature or high pressure, can produce a large amount of aragonite by mineralization in seawater or an aqueous solution in which calcium ions are dissolved, and can achieve a carbon dioxide reduction effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is an electron micrograph of the surface of the polyamidoamine particles prepared in Preparation Example 1 observed.

[0016] Figure 2is an electron micrograph of the particles of Preparation Example 1, in which the particles were immersed in seawater and then recovered after one month of immersion and confirmed in Example 1.

[0017] Figure 3 is an electron micrograph of the particles of Preparation Example 1, in which the particles were immersed in seawater and then recovered after two months of immersion and confirmed in Example 1.

[0018] Figure 4 This is the result of X-ray spectral analysis of the composite particles formed by immersing in seawater in Example 1 into aragonite-type calcium carbonate particles.

[0019] Figure 5 This is a thermogravimetric analysis of the composite particles of aragonite-type calcium carbonate formed in Example 1 when immersed in seawater.

[0020] Figure 6 The change in the total amount of carbon dioxide in seawater over 15 days from the first day after immersing the particles in seawater in Example 1 is shown. DETAILED DESCRIPTION

[0021] Hereinafter, the present invention will be described in more detail. However, the following specific examples or exemplary embodiments are only references for describing the present invention in detail, and the present invention is not limited thereto and can be implemented in various forms.

[0022] In addition, unless otherwise defined, all technical terms and scientific terms have the same meaning as commonly understood by those skilled in the art to which the present invention belongs. The terms used herein are only used to effectively describe specific specific examples and are not intended to limit the present invention.

[0023] Furthermore, singular forms used in the specification and the appended claims may be intended to include plural forms as well, unless the context indicates otherwise.

[0024] In addition, unless specifically described to the contrary, “comprising” any element will be understood to imply the further inclusion of other elements rather than excluding any other elements.

[0025] An exemplary embodiment of the present invention provides a method for preparing carbon dioxide capture composite particles, comprising: The polyamidoamine particles are immersed in seawater or an aqueous solution in which calcium ions are dissolved, and the solution is maintained at room temperature under normal pressure to prepare carbon dioxide capture composite particles, wherein calcium carbonate particles are formed on the surface of the polyamidoamine particles.

[0026] In one exemplary embodiment, the calcium carbonate particles may be aragonite calcium carbonate particles.

[0027] In one exemplary embodiment, after immersing the polyamidoamine particles in seawater or an aqueous solution in which calcium ions are dissolved, the calcium carbonate particles may be formed under the condition that the pH becomes 8 or more by an amine derivative generated when the polyamidoamine particles are decomposed.

[0028] In one exemplary embodiment, 50 mg or more of the polyamidoamine particles may be used based on 200 mL of seawater or an aqueous solution in which calcium ions are dissolved.

[0029] In an exemplary embodiment, seawater or an aqueous solution in which calcium ions are dissolved may have a Ca content of 0.04 g / kg-water or more. 2+ Concentration and 0.02 g / kg-water or higher CO3 2- concentration.

[0030] In one exemplary embodiment, the polyamidoamine particles may be cross-linked particles prepared from a multifunctional amine monomer having at least two or more amine groups and a multifunctional acrylamide monomer having at least two or more acrylic groups.

[0031] In one exemplary embodiment, the polyamidoamine particles may be obtained by reacting a multifunctional amine monomer and an acrylamide monomer in a molar ratio of 1:0.8-2.5.

[0032] In one exemplary embodiment, the multifunctional amine monomer may be a diamine having two primary amine groups, and the multifunctional acrylamide monomer may have two acryl groups.

[0033] In an exemplary embodiment, the polyamidoamine particles may have a particle size of 10 nm to 80 mm, but are not limited thereto.

[0034] Another exemplary embodiment of the present invention provides a carbon dioxide capture composite particle, wherein calcium carbonate particles are formed on the surface of polyamidoamine particles.

[0035] In one exemplary embodiment, the calcium carbonate particles may be aragonite calcium carbonate particles.

[0036] In one exemplary embodiment, in the carbon dioxide capture composite particles, aragonite calcium carbonate particles meet each other and grow on the surface of the polyamidoamine particles.

[0037] In an exemplary embodiment, the carbon dioxide capture composite particles may have a carbon dioxide fixation efficiency of 50 mg-CO2 / g-polymer or higher.

[0038] Hereinafter, each constituent element of the present invention will be described in more detail.

[0039] Calcium carbonate mainly has three homogeneous substances of calcite, aragonite and vaterite. Among them, aragonite is needle-shaped or orthorhombic particles with a large aspect ratio, and is industrially used in various fields such as rubber, plastics, coating fillers, and papermaking pigments. Aragonite is prepared under high temperature conditions of 60°C or higher or in the presence of magnesium ions. Compared with other forms of calcium carbonate, aragonite has difficult preparation conditions, high costs, and is the most expensive form.

[0040] The inventors of the present invention have found that calcium carbonate particles naturally grow on the surface of polyamidoamine particles because mineralization is performed only by immersing specific amino polymers, especially polyamidoamine particles, in seawater, and in the process, because carbon dioxide in seawater is used for mineralization, a carbon dioxide reduction effect can be expressed simultaneously, which is new and surprising, thereby completing the present invention. In addition, when polyamidoamine particles prepared using specific monomers in a specific molar ratio are used, the effect of growing a large number of aragonite-type calcium carbonate particles is surprisingly found.

[0041] Here, the seawater can be any one of ordinary seawater, desalinated concentrated water, salt water, brine, etc., or a mixture of two or more thereof. The aqueous solution in which calcium ions are dissolved can be artificial seawater, specifically, preferably having a Ca ion concentration of 0.04 g / kg-water or higher. 2+ Concentration, 0.02 g / kg-water or higher CO3 2 -concentrated aqueous solution, because it can form a large amount of calcium carbonate particles, preferably a large amount of aragonite, but not limited thereto.

[0042] In an exemplary embodiment, the polyamidoamine particles are cross-linked particles having a highly branched structure, and polyamidoamine particles including amine and amide bonds (or peptide bonds) are more preferably used to form calcium carbonate. The hydrolysis of the amide allows the polyamidoamine particles to decompose in water. Generally, the amide can be easily hydrolyzed and decomposed in deionized water at 37° C. within two weeks, and can be completely decomposed within three months.

[0043] However, surprisingly, when the polyamide amine particles are immersed in seawater, the polyamide amine particles are partially decomposed and swollen, and calcium carbonate particles, preferably aragonite calcium carbonate particles, are formed and grown in the nanometer-sized holes formed on the surface of the swollen polyamide amine particles. That is, the polyamide amine particles are decomposed to prepare amine derivatives on the surface, resulting in a pH of 8 or higher, and the concentration of carbonate ions is increased to produce an environment that is easy to form calcium carbonate. In addition, it can be considered that the amine functional groups of the decomposed polyamide amine particles capture calcium ions, and the ammonium functional groups thereof capture carbonate ions, thereby locally increasing the concentration of mutual ions, and mineralizing the calcium carbonate on the surface of the polyamide amine particles. In addition, it is considered that calcium carbonate particles are formed and grown in the nanometer-sized holes formed on the surface of the swollen polyamide amine particles. Therefore, it can be surprisingly provided that a large amount of stable calcium carbonate particles are produced in a large amount of seawater at room temperature under normal pressure. Furthermore, in this process, a carbon dioxide fixation efficiency of 50 mg-CO2 / g-polymer or more, 60 mg-CO2 / g-polymer or more, preferably 100 mg-CO2 / g-polymer or more, more preferably 200 mg-CO2 / g-polymer or more can be achieved.

[0044] In an exemplary embodiment, since the condition of pH 8 or higher is formed without adding a separate alkali, based on 200 mL of seawater, 50 mg or more, preferably 100 mg or more of polyamidoamine particles are preferably used to form calcium carbonate particles, particularly aragonite-type calcium carbonate particles, but the present invention is not limited thereto. In the case where the amount of polyamidoamine particles is too small compared to the amount of seawater, the pH is maintained below 8, making it difficult to prepare aragonite.

[0045] In an exemplary embodiment, due to the higher concentration of polyamidoamine particles in seawater, the growth rate of aragonite is higher, and aragonite can be better formed under conditions of pH 8 or higher. Therefore, if necessary, a step of further adding an alkaline material to adjust the pH to 8 or higher may be further included, but by adjusting the content of the polyamidoamine particles without adding a separate alkaline material, the nucleation of aragonite can occur within 10 hours, and aragonite can be formed within a few days to a few months.

[0046] Furthermore, without limitation, when the polyamidoamine particles are immersed in seawater, the process is preferably carried out in the absence of metals or metal ions. Metals or metal ions mean that no material is added to further produce metal materials or metal ions other than the ions themselves present in seawater.

[0047] The polyamidoamine particles may be cross-linked particles prepared from a multifunctional amine monomer having at least two or more amine groups and a multifunctional acrylamide monomer having at least two or more acrylic groups.

[0048] Specifically, a method for preparing polyamidoamine particles may include: a) preparing a polyamidoamine precursor aqueous solution from a multifunctional amine monomer and a multifunctional acrylamide monomer; and b) subjecting the polyamidoamine precursor aqueous solution to inverse suspension polymerization to obtain cross-linked polyamidoamine particles.

[0049] The polyfunctional amine monomer and the polyfunctional acrylamide monomer can be used to prepare a polyamidoamine precursor mixture by Michael addition reaction, wherein the nitrogen atom of the amine reacts with the acryl carbon of the acrylamide. In addition, Michael addition reaction is used for crosslinking reaction to prepare hyperbranched polyamidoamine particles, and also for reverse suspension polymerization method as a subsequent step.

[0050] The polyamidoamine precursor aqueous solution corresponds to an intermediate for preparing cross-linked hyperbranched polyamidoamine particles from a multifunctional amine monomer and a multifunctional acrylamide monomer, and is a mixture formed by oligomeric monomers. For example, the polyamidoamine precursor mixture may include an oligomer obtained by reacting one amine monomer and one acrylamide monomer, an oligomer obtained by reacting two amine monomers and one acrylamide monomer, an oligomer obtained by reacting one amine monomer and two acrylamide monomers, an oligomer obtained by reacting two amine monomers and two acrylamide monomers, an oligomer obtained by reacting three amine monomers and two acrylamide monomers, an oligomer obtained by reacting two amine monomers and three acrylamide monomers, and the like.

[0051] As specific amine compounds and acrylamide compounds, in the case of using alkylenediamine (A) and bisacrylamide monomer (B), when each monomer is used to prepare a polyamidoamine precursor mixture, a linear oligomer compound such as AB, ABA, BAB, A-BA-B, BABA, ABABA, BABAB, . . . can be obtained, and the polyamidoamine precursor mixture refers to a mixture thereof.

[0052] Furthermore, in the case of alkylenediamine, since one amine group may undergo Michael addition reaction with acrylamide twice, branched oligomer compounds in which two acrylamides are bonded to one amine group as well as linear oligomer compounds can be obtained, and the polyamidoamine precursor mixture in the present invention is also meant to contain them.

[0053] The multifunctional amine monomer used in the present invention may have at least two or more amine groups in one monomer. That is, it may be a diamine, triamine or polyamine having two or more amine groups at the end of the alkylene group, and may include an amine group instead of a hydrogen atom in the middle of the alkylene group, or have an alkyl group including an amine group instead of a hydrogen substituted in the middle of the alkylene group. In the case of a diamine, since one amine group can undergo a Michael addition reaction with two acrylamides, the primary diamine can undergo an additional crosslinking reaction.

[0054] In an exemplary embodiment, the multifunctional amine monomer can be ethylenediamine, 1,2-diaminopropane, 1,4-diaminobutane, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tris(2-aminoethyl)amine, diaminocyclohexane, pentaethylenehexamine, 2-aminoethylpiperazine, etc., and is not limited thereto, and can preferably be ethylenediamine, 1,4-butanediamine, diethylenetriamine, etc.

[0055] In an exemplary embodiment, the multifunctional acrylamide monomer may have at least two or more acryl groups in one monomer, and the number of acryl groups in the multifunctional acrylamide monomer may be preferably 2 or 3, more preferably 2.

[0056] In an exemplary embodiment of the present invention, the multifunctional amine monomer may be a diamine having two primary amine groups in one monomer, and the multifunctional acrylamide monomer may have two acryl groups in one monomer.

[0057] Examples of the multifunctional acrylamide monomer may be N,N'-methylenebisacrylamide, N,N'-(1,2-dihydroxyethylene)bisacrylamide, N,N'-ethylenebisacrylamide, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, and the like, but are not limited thereto, and may preferably be N,N'-methylenebisacrylamide or N,N'-ethylenebisacrylamide.

[0058] In an exemplary embodiment, when the reaction occurs in an aqueous solution state, the step of preparing the polyamide amine precursor mixture can be easily performed by selecting monomers having a solubility difference in water between the monomers. That is, although the monomer having a large solubility difference in water is first dissolved in water to form an aqueous solution state, and then the monomer that is not well dissolved in water is added at one time, the monomer that is not well dissolved in water has a lower solubility in water, and finally the monomer that is not well dissolved in water can be slowly added to the aqueous solution in which the monomer that is well dissolved in water is dissolved.

[0059] In an exemplary embodiment, for example, in the case of preparing the polyamidoamine precursor mixture by the Michael addition reaction of ethylenediamine and N,N-methylenebisacrylamide, ethylenediamine may exist in a state of being well dissolved in the aqueous solution phase as a B4 monomer well dissolved in water. However, since N,N'-methylenebisacrylamide as an A2 monomer is not well dissolved in water, even in the case of adding all N,N'-methylenebisacrylamide to the ethylenediamine aqueous solution at once, due to the difference in solubility in water, N,N'-methylenebisacrylamide does not react all together with ethylenediamine, and in the initial state of the reaction, since ethylenediamine is present in the aqueous solution in an absolute majority, the terminal of the polyamidoamine precursor mixture mainly includes an amine group.

[0060] Thereafter, as the reaction proceeds, the methylenebisacrylamide slowly dissolves, allowing the Michael addition polymerization reaction to continue to continuously prepare a hyperbranched polyamidoamine precursor mixture.

[0061] In the preparation of the cross-linked hyperbranched polyamidoamine particles of the present invention, the degree of cross-linking can be adjusted by changing each molar ratio of the multifunctional monomers without using other cross-linking agents.

[0062] Without being limited thereto, the polyfunctional amine monomer and the polyfunctional acrylamide monomer react in a molar ratio of 1:0.8 to 2.5 to prepare calcium carbonate, preferably in a molar ratio of 1:1 to 1.5 to prepare aragonite calcium carbonate, and have excellent carbon dioxide capture efficiency. With the increase of the content of the polyfunctional acrylamide monomer, the degree of crosslinking increases, and when the crosslinking degree is too much, the moisture content decreases, making it difficult for the monomer to swell in seawater, thereby hindering the preparation of aragonite. However, the present invention is not limited to the molar ratio.

[0063] In the present invention, the reverse suspension polymerization can be carried out without a stabilizer, or together with a stabilizer by dispersing in an organic solvent 2 to 20 times the volume of the polyamidoamine precursor at 30 to 80° C. In an exemplary embodiment, when an aqueous solution of the polyamidoamine precursor mixture is dispersed in a water-insoluble solvent such as toluene or cyclohexane using a suitable stabilizer, the reverse suspension polymerization can be carried out, and as the polymerization reaction proceeds, crosslinking occurs to form size-regulated hyperbranched polyamidoamine particles.

[0064] In an exemplary embodiment, the solvent used for the reverse suspension polymerization can be any one selected from alkanes having 5 to 12 carbon atoms, cycloalkanes having 5 to 12 carbon atoms, and aromatic hydrocarbons having 6 to 12 carbon atoms, and the stabilizer can be any one selected from sorbitan esters of fatty acids including Span 60 and Span 80, 12-butyryloxy-9-octadecenoic acid ester, poly(hydroxystearic acid)-co(ethylene oxide) block copolymers, etc., or a mixture of two or more thereof.

[0065] In one exemplary embodiment, the reverse phase suspension polymerization may be performed at 40 to 50° C. for 2 to 5 hours, but is not limited thereto.

[0066] The size of the polyamidoamine particles is not limited but may be in the range of 10 nm to 80 mm, specifically 10 μm to 2000 μm, and more specifically 50 μm to 500 μm. Within this range, calcium carbonate particles may be effectively prepared, but the present invention is not limited thereto.

[0067] According to an exemplary embodiment of the carbon dioxide capture composite particles of the present invention, calcium carbonate particles are formed on the surface of polyamidoamine particles, and as a more specific exemplary embodiment, aragonite calcium carbonate particles meet each other and grow on the surface of polyamidoamine particles.

[0068] In an exemplary embodiment, the aragonite calcium carbonate particles can grow to more than 50%, particularly 50 to 100%, of the surface of the polyamidoamine particles. Since the surface area can be easily measured by photographs using SEM or the like, it will not be further described herein.

[0069] The carbon dioxide capture composite particles according to an exemplary embodiment of the present invention may provide an effect of carbon dioxide fixation efficiency of 50 mg-CO2 / g-polymer or higher, preferably 100 mg-CO2 / g-polymer or higher, more preferably 200 mg-CO2 / g-polymer or higher.

[0070] The present invention is described in more detail below in conjunction with Examples and Comparative Examples. However, the following Examples and Comparative Examples are only used to describe an embodiment of the present invention in more detail and do not limit the present invention in any way.

[0071] <Evaluation of physical properties> 1. Mineralization of carbon dioxide in seawater To calculate the amount of carbon dioxide fixed by mineralization of the amine-based polymer mixture prepared in the following examples, the total carbon dioxide and alkalinity were measured using a dissolved inorganic carbon / alkalinity analyzer before and after the addition of the polymer, and then the CO2 reduced in the seawater was calculated. The total amount of carbon dioxide before and after the polymer was added to the seawater was expressed as C0 and C1, and was evaluated by the following equation 1. The amount of seawater used was V, and the mass of the added polymer was MO.

[0072] [Equation 1] Total carbon dioxide = [H2CO3] + [HCO 3- ]+[CO3 2- ] Total carbon dioxide (μmol / kg seawater) = C0-C1 The amount of carbon dioxide per gram of polymer (mmol) = (C0-C1) × V / M0 × 0.001 The amount of carbon dioxide per gram of polymer (mg) = (C0-C1) × V / M0 × 0.001 × 44 2. Thermogravimetric analysis In order to calculate the amount of the mineralized polyamidoamine particles in the examples, a thermogravimetric analyzer (TGA, Pyris1, PerkinElmer, USA) was used to analyze the ratio of polymer (polyamidoamine particles) to minerals. The amount of minerals was based on the amount at 550°C before CaCO3 pyrolysis and was evaluated by the following equation 2. The weight percentage of the polymer at 550°C before mineralization and the weight percentage of the polymer at 550°C after mineralization were expressed as W0 and W1, respectively, and the mass of the particles after mineralization was expressed as Ms.

[0073] [Equation 2] Mineral content (mg) = (W1-W0) / 100×Ms [Equation 3] The amount of carbon dioxide per gram of polymer = (Mm×44 / 100.09) / M0 Wherein the amount of mineral (g) is denoted as Mm, and the mass of polymer before mineralization is denoted as M0.

[0074] 3. Mineralization of carbon dioxide in seawater To calculate the amount of carbon dioxide fixed by mineralization of the polyamidoamine particles in the following examples, the method of the dissolved inorganic carbon / alkalinity analyzer and the method using the mineral ratio obtained by thermogravimetric analysis were used.

[0075] [Preparation Example 1] 0.6 g (10 mmol) of ethylenediamine (EDA) and 1.541 g (10 mmol) of N,N'-methylenebisacrylamide (MBA) were added to a 1-neck round-bottom flask in the same molar ratio, 4 mL of distilled water was added thereto, and stirred until the solution became a homogeneous mixture.

[0076] 0.02 g of Span 60 (sorbitan stearate) was dissolved in 16 mL of toluene, and the solution was added to a 30-necked round-bottom flask containing the prepared precursor aqueous solution, reacted at 45 °C for 3.5 hours while blowing nitrogen, washed with methanol and filtered. The obtained particles were vacuum dried at 60 °C for 24 hours.

[0077] The cross-linked polyamidoamine particles of Example 1 had an average particle size of 280 μm and a swelling ratio of 9.25 g / g.

[0078] Figure 1 is an electron micrograph of the crosslinked polyamidoamine particles according to Preparation Example 1. Figure 1, confirming that the particles have spherical shape and smooth surface.

[0079] [Preparation Example 2] Polyamidoamine particles were prepared in the same manner as in Preparation Example 1, except that 8 mmol of EDA and 12 mmol of MBA were used.

[0080] [Preparation Example 3] Polyamidoamine particles were prepared in the same manner as in Preparation Example 1, except that 8 mmol of EDA and 16 mmol of MBA were used.

[0081] [Preparation Example 4] Polyamidoamine particles were prepared in the same manner as in Preparation Example 1, except that 12 mmol of EDA and 8 mmol of MBA were used.

[0082] [Preparation Example 5] Polyamidoamine particles were prepared in the same manner as in Preparation Example 1, except that 7 mmol of EDA and 21 mmol of MBA were used.

[0083] [Example 1] The carbon dioxide mineralization of the polyamidoamine particles prepared in Preparation Example 1 was evaluated using real seawater. The real seawater was filtered through a 5 μm filter paper to filter out impurities, 100 mg of the polyamidoamine particles were immersed in 200 mL of the filtered seawater, the solution was allowed to stand at room temperature of 20° C., and the polymer samples were confirmed after one month and two months. After a period of time, the mineralized polyamidoamine particles were recovered, the salt remaining on the surface was washed with secondary distilled water, and dried at 50° C.

[0084] Figure 2 is an electron micrograph of the particles of Preparation Example 1, wherein the particles were immersed in seawater and then recovered and confirmed after one month, Figure 3 This is an electron micrograph of particles that were recovered and confirmed two months later. Figure 2 and Figure 3 As shown in Figure 3, it was confirmed that scaly aragonite grew on the particle surface.

[0085] The results of X-ray diffraction analysis according to the evaluation method are Figure 4 Shown in.

[0086] According to the results of thermogravimetric analysis of the evaluation method Figure 5 Shown in.

[0087] In addition, the total amount of carbon dioxide changed from the first day to the fifth day after immersion in seawater. Figure 6 Shown in.

[0088] [Example 2] The experiment was conducted in the same manner as in Example 1, except that the polyamidoamine particles prepared in Preparation Example 2 were used instead of the polyamidoamine particles prepared in Preparation Example 1.

[0089] [Example 3] The experiment was conducted in the same manner as in Example 1, except that the polyamidoamine particles prepared in Preparation Example 3 were used instead of the polyamidoamine particles prepared in Preparation Example 1.

[0090] [Example 4] The experiment was carried out in the same manner as in Example 1, except that a mixture having the same Ca as that of seawater was prepared and used. 2+ Concentration = 0.41g / kg - water and CO3 2- Concentration = 0.016g / kg-water solution to replace seawater (Ca 2+ Concentration = 0.41g / kg-water, CO3 2- Concentration = 0.016 g / kg-water).

[0091] [Example 5] The experiment was conducted in the same manner as in Example 1, except that 0.15 g of the polyamidoamine particles prepared in Preparation Example 1 was used and immersed in 5 L of seawater so that the pH was maintained at 8.0 or less even if the amine-based polymer was hydrolyzed.

[0092] [Comparative Example 1] The experiment was performed in the same manner as in Example 1, except that polylactic acid particles were used instead of the polyamidoamine particles prepared in Preparation Example 1.

[0093] [Comparative Example 2] The experiment was conducted in the same manner as in Example 1, except that poly(butylene succinate) particles were used instead of the polyamidoamine particles prepared in Preparation Example 1.

[0094] [Comparative Example 3] The experiment was conducted in the same manner as in Example 1, except that distilled water was used instead of seawater. As a result, it was confirmed that the polyamidoamine particles were completely decomposed.

[0095] [Comparative Example 4] The experiment was carried out in the same manner as in Example 1, except that a Ca 2+ Concentration = 0.03 g / kg - water and CO3 2- Concentration = 0.001 g / kg-water solution to replace seawater (Ca 2+ Concentration = 0.41g / kg-water, CO3 2-Concentration = 0.016 g / kg-water).

[0096] [Comparative Example 5] The experiment was conducted in the same manner as in Example 1, except that the polyamidoamine particles prepared in Preparation Example 4 were used instead of the polyamidoamine particles prepared in Preparation Example 1.

[0097] [Comparative Example 6] The experiment was conducted in the same manner as in Example 1, except that the polyamidoamine particles prepared in Preparation Example 5 were used instead of the polyamidoamine particles prepared in Preparation Example 1.

[0098] [Table 1] As shown in Table 1, it was confirmed that composite particles on which aragonite-type calcium carbonate was formed were produced even in seawater or artificial seawater.

[0099] As shown in Examples 1 to 3, it was confirmed that when preparing polyamidoamine crosslinked particles, adjusting the molar ratio of the monomers can better form aragonite calcium carbonate. Specifically, it was confirmed that when MBA was used in an equal molar ratio to EDA or in excess, aragonite was formed, and aragonite was optimally formed in the range of a molar ratio of 1:0.8 to 2.5, and the carbon dioxide adsorption efficiency was increased.

[0100] Furthermore, as shown in Example 4, it was confirmed that aragonite-type calcium carbonate was also formed in artificial seawater.

[0101] Furthermore, as shown in Example 5, it was confirmed that after immersing a small amount of polyamidoamine cross-linked particles in seawater, under a pH condition of less than 8, aragonite was not well formed.

[0102] As shown in Comparative Examples 1 and 2, it was confirmed that aragonite was not formed when different kinds of polymer particles were used.

[0103] As shown in Comparative Example 3, it was confirmed that the polyamidoamine cross-linked particles were decomposed in distilled water.

[0104] As shown in Comparative Example 4, it was confirmed that aragonite was not formed in artificial seawater, which was prepared to have a lower Ca content than seawater. 2+ Concentration and CO3 2- concentration.

[0105] As shown in Comparative Examples 5 and 6, it was confirmed that when the ratio of EDA to MBA was greater than or less than the limit ratio, polyamidoamine cross-linked particles were not formed or aragonite was not formed.

[0106] As described above, the method used in the present invention is a method of fixing carbon dioxide in seawater or an aqueous solution in which calcium ions are dissolved by mineralization, and does not require a separate experimental device, and is capable of capturing carbon dioxide under ordinary seawater conditions at room temperature and normal pressure, and is therefore very effective. In addition, very high capture efficiencies of 263 mg-CO2 / g-polymer (dissolved inorganic carbon / alkalinity analyzer); 158 mg-CO2 / g-polymer (thermogravimetric analysis) were shown.

[0107] Above, although the present invention has been described by specific matters and specific exemplary embodiments, they are only provided to help the overall understanding of the present invention. Therefore, the present invention is not limited to the exemplary embodiments. According to this specification, various modifications and changes can be made by those skilled in the art to which the present invention belongs. Therefore, the spirit of the present invention should not be limited to the above-described exemplary embodiments, and the appended claims and equivalent or equivalent modifications to the claims are intended to fall within the scope and spirit of the present invention.

Claims

1. A method for preparing carbon dioxide capture composite particles, the method comprising: The polyamidoamine particles are immersed in seawater or an aqueous solution in which calcium ions are dissolved, and the solution is maintained at room temperature under normal pressure to prepare carbon dioxide capture composite particles, wherein calcium carbonate particles are formed on the surface of the polyamidoamine particles.

2. The method for preparing carbon dioxide capture composite particles according to claim 1, wherein: The calcium carbonate particles are aragonite calcium carbonate particles.

3. The method for preparing carbon dioxide capture composite particles according to claim 1, wherein: After the polyamidoamine particles are immersed in seawater or an aqueous solution in which calcium ions are dissolved, the calcium carbonate particles are formed under the condition that the pH becomes 8 or more due to amine derivatives generated when the polyamidoamine particles are decomposed.

4. The method for preparing carbon dioxide capture composite particles according to claim 3, wherein: Based on 200 mL of the seawater or the aqueous solution in which calcium ions are dissolved, 50 mg or more of the polyamidoamine particles are used.

5. The method for preparing carbon dioxide capture composite particles according to claim 1, wherein: The seawater or the aqueous solution in which calcium ions are dissolved has a Ca content of 0.04 g / kg-water or more. 2+ Concentration and 0.02 g / kg-water or higher CO3 2- concentration.

6. The method for preparing carbon dioxide capture composite particles according to claim 1, wherein: The polyamidoamine particles are crosslinked particles prepared from a multifunctional amine monomer having at least two or more amine groups and a multifunctional acrylamide monomer having at least two or more acrylic groups.

7. The method for preparing carbon dioxide capture composite particles according to claim 6, wherein: The polyamidoamine particles are obtained by reacting the multifunctional amine monomer and the acrylamide monomer in a molar ratio of 1:0.8-2.

5.

8. The method for preparing carbon dioxide capture composite particles according to claim 6, wherein: The multifunctional amine monomer is a diamine having two primary amine groups, and the multifunctional acrylamide monomer has two acryl groups.

9. The method for preparing carbon dioxide capture composite particles according to claim 1, wherein: The polyamidoamine particles have a particle size of 10 nm to 80 mm.

10. Carbon dioxide capture composite particles prepared according to the method of any one of claims 1 to 9, wherein: Calcium carbonate particles are formed on the surface of the polyamidoamine particles.

11. The carbon dioxide capture composite particle according to claim 10, wherein: The calcium carbonate particles are aragonite calcium carbonate particles.

12. The carbon dioxide capture composite particle according to claim 11, wherein: In the carbon dioxide capture composite particles, the aragonite calcium carbonate particles meet each other and grow on the surface of the polyamidoamine particles.

13. The carbon dioxide capture composite particle according to claim 10, wherein: The carbon dioxide capture composite particles have a carbon dioxide fixation efficiency of 50 mg-CO2 / g-polymer or higher.

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