Composite porous spherical particle for carbon dioxide adsorption and preparation method thereof

Abstract

The invention relates to the technical field of carbon neutralization and mine safety, in particular to composite porous spherical particles for carbon dioxide adsorption and a preparation method of the composite porous spherical particles. The problem that existing porous spherical particles are limited in adsorption capacity is solved. According to the composite porous spherical particle, mineralized nano carbide slag is used as a matrix, a polymer network formed by methyl methacrylate and trimethylolpropane triacrylate is deposited on the surface, and an ordered organic-inorganic composite structure is formed; after gamma-aminopropyltriethoxysilane grafting is carried out, polyethyleneimine is loaded on grafted nano carbide slag porous spherical particles through a physical impregnation method, so that carbon dioxide molecules can be efficiently and stably adsorbed, high-performance operation and economic benefits of the particles within a long time are ensured, the porous spherical particles adsorb a large amount of CO2 and then are injected into a goaf, and the goaf is filled with the carbon dioxide. Rapid plugging of the mine goaf is achieved, safe mining of the mine is facilitated, and integration of carbon sequestration and disaster prevention and control is achieved.

Description

Technical Field

[0001] This invention relates to the field of carbon neutrality and mine safety technology, specifically to a composite porous spherical particle for carbon dioxide adsorption and its preparation method. Background Technology

[0002] Carbon dioxide is one of the main greenhouse gases causing global warming. To mitigate its negative environmental impact, researchers have explored various methods to capture and store atmospheric carbon dioxide. A common strategy is to use specific materials to adsorb carbon dioxide, which not only helps reduce the concentration of carbon dioxide in the atmosphere but also facilitates subsequent processing and utilization. Currently, a wide variety of materials are available for adsorbing carbon dioxide, including activated carbon and zeolite molecular sieves. However, these materials generally suffer from limited adsorption capacity. This invention provides a composite porous spherical particle for carbon dioxide adsorption and its preparation method, aiming to improve existing carbon dioxide adsorption technologies. Summary of the Invention

[0003] In order to overcome the above-mentioned technical problems, the present invention aims to provide a composite porous spherical particle for carbon dioxide adsorption and a method for preparing the same, which solves the problem of limited adsorption capacity of existing porous spherical particles.

[0004] The objective of this invention can be achieved through the following technical solutions: In a first aspect, this application provides a method for preparing composite porous spherical particles for carbon dioxide adsorption, comprising the following steps: Step A1: Place the carbide slag in a drying oven and dry it at 100-110℃. After grinding, sieve it through a 150μm sieve to obtain pretreated carbide slag. Step A2: Add the pretreated carbide slag and deionized water to a single-necked flask equipped with a stirrer, stir at 600 r / min for 10 min, and introduce carbon dioxide at a flow rate of 300 mL / min until the pH of the suspension is 6-7. Stop introducing carbon dioxide, centrifuge, place in a drying oven and dry at 60℃ for 3-4 h, grind to obtain mineralized nano carbide slag. Step A3: Add the mineralized nano carbide slag and deionized water into a single-necked flask and sonicate for 15 minutes to obtain a mineralized nano carbide slag suspension. Step A4: Add methyl methacrylate, trimethylolpropane triacrylate, polyoxypropylene-polyoxyethylene copolymer, ethanol and deionized water to a single-necked flask equipped with a stirrer, stir at 800-1000 r / min for 5-10 min, add the mineralized nano carbide slag suspension dropwise with a syringe and stir for 15-20 min to obtain an emulsion; Step A5: Add polyvinyl alcohol, ammonium persulfate and deionized water to a single-necked flask equipped with a stirrer, transfer to an oil bath, add the emulsion at 40°C, stir at 250 r / min until the emulsion is dispersed into spherical particles, add tetramethylethylenediamine to solidify for 1 h, sieve with a sieve, and place in a forced-air drying oven to dry at 65°C for 24 h to obtain porous spherical particles based on nano-calcium carbide slag; Step A6: Add γ-aminopropyltriethoxysilane and ethanol to a three-necked flask equipped with a stirrer, reflux condenser and thermometer, stir for 5-10 min, add porous spherical particles based on nano-carbide slag, reflux at 85℃ for 12 h, vacuum filter, wash with deionized water, place in a drying oven and dry at 100℃ for 12 h to obtain grafted porous spherical particles based on nano-carbide slag. Step A7: Add polyethyleneimine and methanol to a single-necked flask equipped with a stirrer and stir for 5-10 minutes. Add grafted nano-carbide slag porous spherical particles and soak for 24 hours. Transfer to a forced-air drying oven and soak at 50°C for 5 hours. Place in a fume hood and let stand for 1-2 hours. Place in a drying oven and vacuum dry for 20-24 hours to obtain composite porous spherical particles for carbon dioxide adsorption.

[0005] As a further aspect of the present invention: the ratio of the amount of pretreated carbide slag and deionized water used in step A2 is 10-30g: 100-300mL.

[0006] As a further aspect of the present invention: the ratio of mineralized nano-calcium carbide slag to deionized water in step A3 is 0.6-1.2g:40-80mL.

[0007] As a further embodiment of the present invention: the ratio of methyl methacrylate, trimethylolpropane triacrylate, polyoxypropylene-polyoxyethylene copolymer, ethanol, deionized water and mineralized nano-calcium carbide slag suspension in step A4 is 5.7-11.4g: 4.6-9.2g: 2.15-4.3g: 8-16mL: 40-80mL.

[0008] As a further aspect of the present invention: the CAS number of the polyoxypropylene-polyoxyethylene copolymer mentioned in step A4 is 106392-12-5.

[0009] As a further embodiment of the present invention: the ratio of polyvinyl alcohol, ammonium persulfate, deionized water, emulsion and tetramethylethylenediamine used in step A5 is 3.2-6.4g: 0.32-0.64g: 320-640mL: 48-96mL: 2-4mL.

[0010] As a further aspect of the present invention: the CAS number of the polyvinyl alcohol mentioned in step A5 is 9002-89-5.

[0011] As a further aspect of the present invention: the ratio of γ-aminopropyltriethoxysilane, ethanol and porous spherical particles based on nano-calcium carbide slag used in step A6 is 5-10 mL: 250-500 mL: 5-10 g.

[0012] As a further aspect of the present invention: the ratio of polyethyleneimine, methanol and grafted nano-carbide slag porous spherical particles in step A7 is 7.5-15g: 250-500mL: 2.5-5g.

[0013] As a further aspect of the present invention: the CAS number of the polyethyleneimine mentioned in step A7 is 9002-98-6.

[0014] The beneficial effects of this invention are: This invention discloses a composite porous spherical particle for carbon dioxide adsorption and its preparation method. The method involves mineralizing calcium carbide slag to obtain nano-calcium carbonate, polymerizing methyl methacrylate and trimethylolpropane triacrylate to form a polymer cross-linking network on the surface of the mineralized nano-calcium carbide slag, and then curing it with ethanol to obtain the composite porous spherical particle for carbon dioxide adsorption. The porous structure provides sufficient adsorption sites. Furthermore, the porous spherical particle is diamined to enhance carbon dioxide capture, thereby improving adsorption efficiency.

[0015] To prepare a composite porous spherical particle for carbon dioxide adsorption, mineralized nano-carbide slag was first prepared. The slag was dried to remove impurities and then carbonized under the action of carbon dioxide to obtain calcium carbonate. Polyoxypropylene-polyoxyethylene copolymer was used as an emulsifier to form stable O / W type droplets. Methyl methacrylate and trimethylolpropane triacrylate formed a polymer network through a free radical chain polymerization reaction initiated by ammonium persulfate-tetramethylethylenediamine. Calcium carbonate was directionally deposited in the polymer network, forming an ordered organic-non-carbonate system. The composite structure uses polyvinyl alcohol as a film-forming agent mixed with the emulsion. After curing, a stable interpenetrating network structure is formed, ensuring pore connectivity and structural integrity. Ethanol acts as a pore-forming agent, occupying pore space in the emulsion. During the drying stage, the ethanol evaporates, leaving pores, resulting in porous spherical particles based on nano-carbide slag. The silanol generated by the hydrolysis of γ-aminopropyltriethoxysilane in ethanol undergoes dehydration condensation with the hydroxyl groups on the surface of the porous spherical particles based on nano-carbide slag, forming Si-O-Si covalent bonds, thus obtaining grafted porous spherical particles based on nano-carbide slag. By loading polyethyleneimine onto grafted nano-carbide slag porous spherical particles through a physical impregnation method, composite porous spherical particles for carbon dioxide adsorption are obtained. The high specific surface area increases the contact opportunities between the particles and carbon dioxide, thereby improving the adsorption efficiency. Grafting γ-aminopropyltriethoxysilane before impregnation with polyethyleneimine can enhance the connection between the amino group and the nano-carbide slag-based porous spherical particles, thereby improving the stability of the bifunctional material and its carbon dioxide adsorption efficiency. After carbon dioxide adsorption, the composite porous material can be used to fill mined-out areas, achieving a three-dimensional high-efficiency use that fully utilizes solid waste, absorbs greenhouse gases, and fills mined-out areas. Detailed Implementation

[0016] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0017] Example 1: This embodiment describes a method for preparing composite porous spherical particles for carbon dioxide adsorption, comprising the following steps: Step A1: Place the carbide slag in a drying oven and dry it at 100℃. After grinding, sieve it through a 150μm sieve to obtain pretreated carbide slag. Step A2: Add 10g of pretreated carbide slag and 100mL of deionized water to a single-necked flask equipped with a stirrer, stir at 600r / min for 10min, and introduce carbon dioxide at a flow rate of 300mL / min until the pH of the suspension reaches 6. Then stop introducing carbon dioxide, centrifuge, place in a drying oven and dry at 60℃ for 3h, grind to obtain mineralized nano carbide slag. Step A3: Add 0.6g of mineralized nano-carbide slag and 40mL of deionized water to a single-necked flask and sonicate for 15min to obtain a mineralized nano-carbide slag suspension. Step A4: Add 5.7g of methyl methacrylate, 4.6g of trimethylolpropane triacrylate, 2.15g of polyoxypropylene-polyoxyethylene copolymer, 8mL of ethanol and 40mL of deionized water to a single-necked flask equipped with a stirrer, stir at 800r / min for 5min, add the mineralized nano carbide slag suspension dropwise with a syringe and stir for 15min to obtain an emulsion; Step A5: Add 3.2g polyvinyl alcohol, 0.32g ammonium persulfate and 320mL deionized water to a single-necked flask equipped with a stirrer, transfer to an oil bath, add 48mL of emulsion at 40℃, stir at 250r / min until the emulsion is dispersed into spherical particles, add 2mL tetramethylethylenediamine to solidify for 1h, sieve with a sieve, and dry in a forced-air drying oven at 65℃ for 24h to obtain porous spherical particles based on nano-carbide slag; Step A6: Add 5 mL of γ-aminopropyltriethoxysilane and 250 mL of ethanol to a three-necked flask equipped with a stirrer, reflux condenser and thermometer, stir for 5 min, add 5 g of nano-carbide slag porous spherical particles, reflux at 85 °C for 12 h, vacuum filter, wash with deionized water, place in a drying oven and dry at 100 °C for 12 h to obtain grafted nano-carbide slag porous spherical particles; Step A7: Add 7.5g of polyethyleneimine and 250mL of methanol to a single-necked flask equipped with a stirrer and stir for 5 minutes. Add 2.5g of grafted nano-carbide slag porous spherical particles and soak for 24 hours. Transfer to a forced-air drying oven and soak at 50℃ for 5 hours. Place in a fume hood and let stand for 1 hour. Place in a drying oven and vacuum dry for 20 hours to obtain composite porous spherical particles for carbon dioxide adsorption.

[0018] Example 2: This embodiment describes a method for preparing composite porous spherical particles for carbon dioxide adsorption, comprising the following steps: Step A1: Place the carbide slag in a drying oven and dry it at 105℃. After grinding, sieve it through a 150μm sieve to obtain pretreated carbide slag. Step A2: Add 20g of pretreated carbide slag and 200mL of deionized water to a single-necked flask equipped with a stirrer, stir at 600r / min for 10min, and introduce carbon dioxide at a flow rate of 300mL / min until the pH of the suspension reaches 6. Then stop introducing carbon dioxide, centrifuge, place in a drying oven and dry at 60℃ for 3.5h, grind to obtain mineralized nano carbide slag. Step A3: Add 0.9g of mineralized nano-carbide slag and 60mL of deionized water to a single-necked flask and sonicate for 15min to obtain a mineralized nano-carbide slag suspension. Step A4: Add 8.55g of methyl methacrylate, 6.9g of trimethylolpropane triacrylate, 3.225g of polyoxypropylene-polyoxyethylene copolymer, 12mL of ethanol and 60mL of deionized water to a single-necked flask equipped with a stirrer, stir at 900r / min for 7min, add the mineralized nano-carbide slag suspension dropwise with a syringe and stir for 17min to obtain an emulsion; Step A5: Add 4.8g polyvinyl alcohol, 0.48g ammonium persulfate and 480mL deionized water to a single-necked flask equipped with a stirrer, transfer to an oil bath, add 72mL of emulsion at 40℃, stir at 250r / min until the emulsion is dispersed into spherical particles, add 3mL tetramethylethylenediamine to solidify for 1h, sieve with a sieve, and dry in a forced-air drying oven at 65℃ for 24h to obtain porous spherical particles based on nano-calcium carbide slag; Step A6: Add 7.5 mL of γ-aminopropyltriethoxysilane and 325 mL of ethanol to a three-necked flask equipped with a stirrer, reflux condenser and thermometer, stir for 7 min, add 7.5 g of nano-carbide slag porous spherical particles, reflux at 85 °C for 12 h, vacuum filter, wash with deionized water, place in a drying oven and dry at 100 °C for 12 h to obtain grafted nano-carbide slag porous spherical particles; Step A7: Add 11.25g of polyethyleneimine and 325mL of methanol to a single-necked flask equipped with a stirrer and stir for 7 minutes. Add 3.25g of grafted nano-carbide slag porous spherical particles and soak for 24 hours. Transfer to a forced-air drying oven and soak at 50℃ for 5 hours. Place in a fume hood and let stand for 1.5 hours. Place in a drying oven and vacuum dry for 22 hours to obtain composite porous spherical particles for carbon dioxide adsorption.

[0019] Example 3: This embodiment describes a method for preparing composite porous spherical particles for carbon dioxide adsorption, comprising the following steps: Step A1: Place the carbide slag in a drying oven and dry it at 110℃. After grinding, sieve it through a 150μm sieve to obtain pretreated carbide slag. Step A2: Add 30g of pretreated carbide slag and 300mL of deionized water to a single-necked flask equipped with a stirrer, stir at 600r / min for 10min, and introduce carbon dioxide at a flow rate of 300mL / min until the pH of the suspension reaches 7. Then stop introducing carbon dioxide, centrifuge, place in a drying oven and dry at 60℃ for 4h, grind to obtain mineralized nano carbide slag. Step A3: Add 1.2g of mineralized nano-carbide slag and 80mL of deionized water to a single-necked flask and sonicate for 15min to obtain a mineralized nano-carbide slag suspension. Step A4: Add 11.4g of methyl methacrylate, 9.2g of trimethylolpropane triacrylate, 4.3g of polyoxypropylene-polyoxyethylene copolymer, 16mL of ethanol and 80mL of deionized water to a single-necked flask equipped with a stirrer, stir at 1000r / min for 10min, add the mineralized nano-calcium carbide slag suspension dropwise with a syringe and stir for 20min to obtain an emulsion; Step A5: Add 6.4g of polyvinyl alcohol, 0.64g of ammonium persulfate and 640mL of deionized water to a single-necked flask equipped with a stirrer, transfer to an oil bath, add 96mL of emulsion at 40℃, stir at 250r / min until the emulsion is dispersed into spherical particles, add 4mL of tetramethylethylenediamine to solidify for 1h, sieve with a sieve, and dry in a forced-air drying oven at 65℃ for 24h to obtain porous spherical particles based on nano-carbide slag; Step A6: Add 10 mL of γ-aminopropyltriethoxysilane and 500 mL of ethanol to a three-necked flask equipped with a stirrer, a reflux condenser and a thermometer. Stir for 10 min, add 10 g of nano-carbide slag porous spherical particles, reflux at 85 °C for 12 h, vacuum filter, wash with deionized water, and dry in a drying oven at 100 °C for 12 h to obtain grafted nano-carbide slag porous spherical particles. Step A7: Add 15g of polyethyleneimine and 500mL of methanol to a single-necked flask equipped with a stirrer and stir for 10min. Add 5g of grafted nano-carbide slag porous spherical particles and soak for 24h. Transfer to a forced-air drying oven and soak at 50℃ for 5h. Place in a fume hood and let stand for 2h. Place in a drying oven and vacuum dry for 24h to obtain composite porous spherical particles for carbon dioxide adsorption.

[0020] Comparative Example 1: This comparative example illustrates a method for preparing composite porous spherical particles for carbon dioxide adsorption, comprising the following steps: Step A1: Place the carbide slag in a drying oven and dry it at 110℃. After grinding, sieve it through a 150μm sieve to obtain pretreated carbide slag. Step A2: Add 30g of pretreated carbide slag and 300mL of deionized water to a single-necked flask equipped with a stirrer, stir at 600r / min for 10min, and introduce carbon dioxide at a flow rate of 300mL / min until the pH of the suspension reaches 7. Then stop introducing carbon dioxide, centrifuge, place in a drying oven and dry at 60℃ for 4h, grind to obtain mineralized nano carbide slag. Step A3: Add 1.2g of mineralized nano-carbide slag and 80mL of deionized water to a single-necked flask and sonicate for 15min to obtain a mineralized nano-carbide slag suspension. Step A4: Add 11.4g of methyl methacrylate, 9.2g of trimethylolpropane triacrylate, 4.3g of polyoxypropylene-polyoxyethylene copolymer, 16mL of ethanol and 80mL of deionized water to a single-necked flask equipped with a stirrer, stir at 1000r / min for 10min, add the mineralized nano-calcium carbide slag suspension dropwise with a syringe and stir for 20min to obtain an emulsion; Step A5: Add 6.4g of polyvinyl alcohol, 0.64g of ammonium persulfate and 640mL of deionized water to a single-necked flask equipped with a stirrer, transfer to an oil bath, add 96mL of emulsion at 40℃, stir at 250r / min until the emulsion is dispersed into spherical particles, add 4mL of tetramethylethylenediamine to solidify for 1h, sieve with a sieve, and dry in a forced-air drying oven at 65℃ for 24h to obtain porous spherical particles based on nano-carbide slag; Step A6: Add 10 mL of γ-aminopropyltriethoxysilane and 500 mL of ethanol to a three-necked flask equipped with a stirrer, reflux condenser and thermometer. Stir for 10 min, add 10 g of porous spherical particles based on nano-carbide slag, reflux at 85 °C for 12 h, vacuum filter, wash with deionized water, and dry in a drying oven at 100 °C for 12 h to obtain composite porous spherical particles for carbon dioxide adsorption.

[0021] Comparative Example 2: This comparative example illustrates a method for preparing composite porous spherical particles for carbon dioxide adsorption, comprising the following steps: Step A1: Place the carbide slag in a drying oven and dry it at 110℃. After grinding, sieve it through a 150μm sieve to obtain pretreated carbide slag. Step A2: Add 30g of pretreated carbide slag and 300mL of deionized water to a single-necked flask equipped with a stirrer, stir at 600r / min for 10min, and introduce carbon dioxide at a flow rate of 300mL / min until the pH of the suspension reaches 7. Then stop introducing carbon dioxide, centrifuge, place in a drying oven and dry at 60℃ for 4h, grind to obtain mineralized nano carbide slag. Step A3: Add 1.2g of mineralized nano-carbide slag and 80mL of deionized water to a single-necked flask and sonicate for 15min to obtain a mineralized nano-carbide slag suspension. Step A4: Add 11.4g of methyl methacrylate, 9.2g of trimethylolpropane triacrylate, 4.3g of polyoxypropylene-polyoxyethylene copolymer, 16mL of ethanol and 80mL of deionized water to a single-necked flask equipped with a stirrer, stir at 1000r / min for 10min, add the mineralized nano-calcium carbide slag suspension dropwise with a syringe and stir for 20min to obtain an emulsion; Step A5: Add 6.4g of polyvinyl alcohol, 0.64g of ammonium persulfate and 640mL of deionized water to a single-necked flask equipped with a stirrer, transfer to an oil bath, add 96mL of emulsion at 40℃, stir at 250r / min until the emulsion is dispersed into spherical particles, add 4mL of tetramethylethylenediamine to solidify for 1h, sieve with a sieve, and dry in a forced-air drying oven at 65℃ for 24h to obtain porous spherical particles based on nano-carbide slag; Step A6: Add 15g of polyethyleneimine and 500mL of methanol to a single-necked flask equipped with a stirrer and stir for 10min. Add 5g of porous spherical particles based on nano-carbide slag and soak for 24h. Transfer to a forced-air drying oven and soak at 50℃ for 5h. Place in a fume hood and let stand for 2h. Place in a drying oven and vacuum dry for 24h to obtain composite porous spherical particles for carbon dioxide adsorption.

[0022] Comparative Example 3: This comparative example illustrates a method for preparing composite porous spherical particles for carbon dioxide adsorption, comprising the following steps: Step A1: Place the carbide slag in a drying oven and dry it at 110℃. After grinding, sieve it through a 150μm sieve to obtain pretreated carbide slag. Step A2: Add 30g of pretreated carbide slag and 300mL of deionized water to a single-necked flask equipped with a stirrer, stir at 600r / min for 10min, and introduce carbon dioxide at a flow rate of 300mL / min until the pH of the suspension reaches 7. Then stop introducing carbon dioxide, centrifuge, place in a drying oven and dry at 60℃ for 4h, grind to obtain mineralized nano carbide slag. Step A3: Add 1.2g of mineralized nano-carbide slag and 80mL of deionized water to a single-necked flask and sonicate for 15min to obtain a mineralized nano-carbide slag suspension. Step A4: Add 11.4g of methyl methacrylate, 9.2g of trimethylolpropane triacrylate, 4.3g of polyoxypropylene-polyoxyethylene copolymer, 16mL of ethanol and 80mL of deionized water to a single-necked flask equipped with a stirrer, stir at 1000r / min for 10min, add the mineralized nano-calcium carbide slag suspension dropwise with a syringe and stir for 20min to obtain an emulsion; Step A5: Add 6.4g of polyvinyl alcohol, 0.64g of ammonium persulfate and 640mL of deionized water to a single-necked flask equipped with a stirrer, transfer to an oil bath, add 96mL of emulsion at 40℃, stir at 250r / min until the emulsion is dispersed into spherical particles, add 4mL of tetramethylethylenediamine to solidify for 1h, sieve with a sieve, and dry in a forced-air drying oven at 65℃ for 24h to obtain porous spherical particles based on nano-carbide slag; Step A6: Add 15g of tetraethylenepentamine and 500mL of methanol to a single-necked flask equipped with a stirrer and stir for 10min. Add 5g of porous spherical particles based on nano-carbide slag and soak for 24h. Transfer to a forced-air drying oven and soak at 50℃ for 5h. Place in a fume hood and let stand for 2h. Place in a drying oven and vacuum dry for 24h to obtain composite porous spherical particles for carbon dioxide adsorption.

[0023] Comparative Example 4: This comparative example illustrates a method for preparing composite porous spherical particles for carbon dioxide adsorption, comprising the following steps: Step A1: Place the carbide slag in a drying oven and dry it at 110℃. After grinding, sieve it through a 150μm sieve to obtain pretreated carbide slag. Step A2: Add 30g of pretreated carbide slag and 300mL of deionized water to a single-necked flask equipped with a stirrer, stir at 600r / min for 10min, and introduce carbon dioxide at a flow rate of 300mL / min until the pH of the suspension reaches 7. Then stop introducing carbon dioxide, centrifuge, place in a drying oven and dry at 60℃ for 4h, grind to obtain mineralized nano carbide slag. Step A3: Add 1.2g of mineralized nano-carbide slag and 80mL of deionized water to a single-necked flask and sonicate for 15min to obtain a mineralized nano-carbide slag suspension. Step A4: Add 11.4g of methyl methacrylate, 9.2g of trimethylolpropane triacrylate, 4.3g of polyoxypropylene-polyoxyethylene copolymer, 16mL of ethanol and 80mL of deionized water to a single-necked flask equipped with a stirrer, stir at 1000r / min for 10min, add the mineralized nano-calcium carbide slag suspension dropwise with a syringe and stir for 20min to obtain an emulsion; Step A5: Add 6.4g of polyvinyl alcohol, 0.64g of ammonium persulfate, and 640mL of deionized water to a single-necked flask equipped with a stirrer, transfer to an oil bath, add 96mL of emulsion at 40℃, stir at 250r / min until the emulsion is dispersed into spherical particles, add 4mL of tetramethylethylenediamine to solidify for 1h, sieve with a sieve, and dry in a forced-air drying oven at 65℃ for 24h to obtain porous spherical particles based on nano-carbide slag.

[0024] Performance testing The porous spherical particles of Examples 1-3 and Comparative Examples 1-4 were tested using a fully automated specific surface area and porosity analyzer to obtain the carbon dioxide adsorption capacity. In the laboratory, experimental containers were used to simulate goaf areas in mines. Apparatus Structure: The experimental container is filled with 1-10cm of crushed rock, with a first inlet / outlet at each end (connected to a porous spherical particle filling device), and a second inlet / outlet (equipped with a pressure gauge and control valve) on the side wall. The filling device integrates a gaseous CO2 source, a foam preparation device, and a particulate fluid generator, and can output high-pressure CO2 fluid containing porous spherical particles.

[0025] Initial pressure test: Close the first inlet / outlet control valve, open the second inlet / outlet control valve, fill with 1MPa high-pressure gas, and record the pressure difference between the two sides.

[0026] Particle filling: Close the second passage, open the first passage, and start the filling device to inject high-pressure CO2 fluid containing porous spherical particles into the container. Due to the alkaline solid waste properties, the particles are retained in the pores of the broken rock, and the CO2 gas is discharged from the first outlet for 15 minutes.

[0027] Verification of sealing effect: Close the first passage again, open the second passage and fill it with 1MPa high-pressure gas, and record the pressure difference change.

[0028] Table 1. Carbon dioxide adsorption capacity of Examples 1-3 and Comparative Examples 1-4 Table 2. Pressure difference values ​​in Examples 1-3 Referring to the table above, based on the comparison between Examples 1-3 and Comparative Examples 1-4, it can be seen that the nano-carbide slag porous spherical particles based on γ-aminopropyltriethoxysilane and polyethyleneimine diaminoation have excellent carbon dioxide adsorption capacity. Based on the comparison between Example 3 and Comparative Example 1, it can be seen that the carbon dioxide adsorption capacity of the nano-carbide slag porous spherical particles based on γ-aminopropyltriethoxysilane and polyethyleneimine double-aminated carbon dioxide adsorption capacity is greater than that of the nano-carbide slag porous spherical particles based on γ-aminopropyltriethoxysilane aminated carbon dioxide adsorption capacity. This indicates that the nano-carbide slag porous spherical particles based on γ-aminopropyltriethoxysilane and polyethyleneimine double-aminated carbon dioxide adsorption capacity has excellent carbon dioxide adsorption capacity. Based on the comparison between Example 3 and Comparative Example 2, it can be seen that the carbon dioxide adsorption capacity of the nano-carbide slag porous spherical particles based on γ-aminopropyltriethoxysilane and polyethyleneimine double-aminated carbon dioxide adsorption capacity is greater than that of the nano-carbide slag porous spherical particles based on polyethyleneimine aminated carbon dioxide adsorption capacity. This indicates that the nano-carbide slag porous spherical particles based on γ-aminopropyltriethoxysilane and polyethyleneimine double-aminated carbon dioxide adsorption capacity has excellent carbon dioxide adsorption capacity. Based on the comparison between Example 3 and Comparative Example 3, it can be seen that the carbon dioxide adsorption capacity of the nano-carbide slag porous spherical particles based on γ-aminopropyltriethoxysilane and polyethyleneimine double-aminated carbon dioxide adsorption capacity is greater than that of the tetraethylenepentamine aminated nano-carbide slag porous spherical particles, indicating that the nano-carbide slag porous spherical particles based on γ-aminopropyltriethoxysilane and polyethyleneimine double-aminated carbon dioxide adsorption capacity has excellent carbon dioxide adsorption capacity. Based on the comparison between Example 3 and Comparative Example 4, it can be seen that the carbon dioxide adsorption capacity of the nano-carbide slag porous spherical particles based on γ-aminopropyltriethoxysilane and polyethyleneimine double-aminated carbon dioxide adsorption is greater than that of the nano-carbide slag porous spherical particles, indicating that the nano-carbide slag porous spherical particles based on γ-aminopropyltriethoxysilane and polyethyleneimine double-aminated carbon dioxide adsorption have excellent carbon dioxide adsorption capacity.

[0029] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0030] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in this application, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing composite porous spherical particles for carbon dioxide adsorption, characterized in that, Includes the following steps: Step A1: Dry the carbide slag, grind it, and then sieve it to obtain pretreated carbide slag; Step A2: Stir the pretreated carbide slag and deionized water, pass carbon dioxide through until the pH of the suspension is 6-7, then stop passing carbon dioxide. After centrifugation, dry and grind to obtain mineralized nano carbide slag. Step A3: Sonicate the mineralized nano-carbide slag and deionized water to obtain a mineralized nano-carbide slag suspension; Step A4: Methyl methacrylate, trimethylolpropane triacrylate, polyoxypropylene polyoxyethylene copolymer, ethanol and deionized water are stirred, and mineralized nano carbide slag suspension is added and stirred to obtain an emulsion; Step A5: Polyvinyl alcohol, ammonium persulfate and deionized water oil bath, emulsion, stir, add tetramethylethylenediamine for curing, sieve, dry to obtain porous spherical particles based on nano carbide slag; Step A6: Stir γ-aminopropyltriethoxysilane and ethanol, add porous spherical particles based on nano-carbide slag, reflux, filter, wash, and dry to obtain grafted porous spherical particles of nano-carbide slag. Step A7: Mix polyethyleneimine and methanol, impregnate with grafted nano-carbide slag porous spherical particles, let stand, and dry to obtain composite porous spherical particles for carbon dioxide adsorption.

2. The method for preparing composite porous spherical particles for carbon dioxide adsorption according to claim 1, characterized in that, The ratio of pretreated carbide slag to deionized water in step A2 is 10-30g: 100-300mL.

3. The method for preparing composite porous spherical particles for carbon dioxide adsorption according to claim 1, characterized in that, The ratio of mineralized nano-carbide slag to deionized water in step A3 is 0.6-1.2g:40-80mL.

4. The method for preparing composite porous spherical particles for carbon dioxide adsorption according to claim 1, characterized in that, In step A4, the ratio of methyl methacrylate, trimethylolpropane triacrylate, polyoxypropylene-polyoxyethylene copolymer, ethanol, deionized water, and mineralized nano-carbide slag suspension is 5.7-11.4g: 4.6-9.2g: 2.15-4.3g: 8-16mL: 40-80mL; the CAS number of the polyoxypropylene-polyoxyethylene copolymer is 106392-12-5.

5. The method for preparing composite porous spherical particles for carbon dioxide adsorption according to claim 1, characterized in that, In step A5, the ratio of polyvinyl alcohol, ammonium persulfate, deionized water, emulsion, and tetramethylethylenediamine is 3.2-6.4g: 0.32-0.64g: 320-640mL: 48-96mL: 2-4mL; the CAS number of the polyvinyl alcohol is 9002-89-5.

6. The method for preparing composite porous spherical particles for carbon dioxide adsorption according to claim 1, characterized in that, In step A6, the ratio of γ-aminopropyltriethoxysilane, ethanol, and porous spherical particles based on nano-calcium carbide slag is 5-10 mL: 250-500 mL: 5-10 g.

7. The method for preparing composite porous spherical particles for carbon dioxide adsorption according to claim 1, characterized in that, In step A7, the ratio of polyethyleneimine, methanol, and grafted nano-carbide slag porous spherical particles is 7.5-15g: 250-500mL: 2.5-5g; the CAS number of the polyethyleneimine is 9002-98-6.

8. A composite porous spherical particle for carbon dioxide adsorption, characterized in that, The composite porous spherical particles for carbon dioxide adsorption were prepared using the method described in any one of claims 1-7.

Images