System for storing carbon dioxide, and applications and methods for storing and transporting carbon dioxide

Abstract

The present application relates to the technical field of CO2 capture and storage by hydrate method, and particularly relates to a system for storing carbon dioxide, application and a carbon dioxide storage and transportation method. The system contains water, perfluorinated compounds and a CO2 hydrate promoter; wherein, taking the sum of the volumes of water and perfluorinated compounds as 100%, the proportion of the perfluorinated compounds is 50-90%; the CO2 hydrate promoter contains an emulsifier, a formation enhancer and a stabilizer. The system for storing carbon dioxide has the advantages of fast CO2 hydrate formation rate, high gas storage capacity, convenient operation and excellent environmental performance, and has a good application prospect in the field of CO2 capture and storage by hydrate method.

Description

Technical Field

[0001] This invention relates to the field of CO2 capture and storage technology using hydrates, specifically to a system and application for storing carbon dioxide and a method for storing and transporting carbon dioxide. Background Technology

[0002] With the continuous emission of greenhouse gases, global warming has become an international issue. Among the various anthropogenic greenhouse gases emitted into the atmosphere, CO2 accounts for the largest proportion. Carbon capture, utilization, and storage (CCS) has become an international research hotspot. To control CO2 emissions in the short term, CCS is considered one of the main strategies with a direct impact on mitigating global warming. Gas hydrates are non-stoichiometric crystalline substances formed by small gas molecules such as CH4 and water molecules under low temperature and high pressure conditions. They are characterized by high enthalpy of formation, non-flammability, and non-toxicity. Similar to CH4 hydrates, CO2 hydrates can also be formed under low temperature and high pressure conditions. These hydrates consist of cage-like water grids and CO2 molecules trapped within these cages. Theoretically, if all the cavities are filled, a 1m³ of water can form a hydrate. 3 CO2 hydrates can be stored for approximately 180 m³ under standard conditions. 3 This is one of the reasons why hydrate technology can be efficiently applied to CO2 gas capture, separation, storage and transportation.

[0003] The formation of CO2 hydrates can be divided into two processes: nucleation and growth. Nucleation refers to the process by which gas and water molecules form crystal nuclei of a critical size after the gas molecules dissolve in the solution to form a saturated solution. Nucleation can occur when the system is in a supercooled or supersaturated state. The hydrate growth process is an exothermic three-phase gas-liquid-solid process. Mass transfer, heat transfer, and momentum transfer in the bulk phase directly affect the reaction. The formation rate of gas hydrates is closely related to factors such as pressure, temperature, degree of supercooling, the degree of system disturbance, and the gas-liquid contact area.

[0004] Currently, the slow CO2 hydrate formation rate and low gas storage capacity are the main reasons hindering the industrial application of CO2 capture and storage technology using hydrates. To improve the CO2 hydrate formation rate, the slurry hydrate method has become a new technology that has attracted much attention from academia and industry in recent years. Its principle is to use an aqueous phase and a hydrophobic phase system. Before hydrate formation, the aqueous phase exists in the form of small droplets, thereby increasing the gas-liquid contact area and enhancing hydrate nucleation. After the hydrate particles are formed, they are uniformly dispersed in the hydrophobic phase and exist stably in a slurry form.

[0005] Currently, this method is mainly applied to the enhancement of hydrates of nonpolar molecules such as CH4 and C2H6, typically employing a (aqueous phase + organic liquid hydrocarbon phase) system, where the liquid hydrocarbon phase is often diesel oil. Due to the similarity of miscibility between diesel oil and nonpolar molecules like CH4, the liquid hydrocarbon phase exhibits high absorption and diffusion capabilities for gas molecules, which is beneficial for the rapid nucleation and growth of hydrates. However, CO2 molecules are polar molecules with low solubility in the organic liquid hydrocarbon phase, failing to provide effective absorption and diffusion capabilities, thus limiting its application. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems of slow CO2 hydrate formation rate and low gas storage capacity in existing technologies, and to provide a system and application for storing carbon dioxide, as well as a method for carbon dioxide storage and transportation. This system provides new ideas for enriching the theory and industrial application of CO2 capture technology using hydrates.

[0007] To achieve the above objectives, the present invention provides a system for storing carbon dioxide, the system containing water, a perfluorinated compound, and a CO2 hydrate promoter;

[0008] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 50-90% of the total volume.

[0009] The CO2 hydrate promoter contains emulsifiers, generation enhancers, and stabilizers.

[0010] Preferably, the perfluorinated compound is selected from one or more of perfluorohexanone, methyl perfluorodecanoate, ethyl perfluoropentanone, perfluoropropyl vinyl ether, and perfluoro(2-butyltetrahydrofuran).

[0011] Preferably, the weight ratio of emulsifier to water is 0.01-0.1:100.

[0012] Preferably, the emulsifier is an anionic surfactant or an amphoteric surfactant;

[0013] Preferably, the weight ratio of the anionic surfactant to the amphoteric surfactant is 1:0.1-10.

[0014] Preferably, the anionic surfactant is selected from one or more of diethanolamine dodecyl sulfate, triethanolamine dodecyl sulfate, and sodium polyoxyethylene dodecyl ether sulfate.

[0015] Preferably, the zwitterionic surfactant is a betaine-type zwitterionic surfactant.

[0016] Preferably, the betaine-type zwitterionic surfactant is selected from one or more of dodecyl dimethyl betaine, 3-sulfopropyltetradecyl dimethyl betaine, 3-sulfopropylhexadecyl dimethyl betaine, lauramide propyl betaine, and cocamidopropyl betaine.

[0017] Preferably, the strengthening agent is a tetraalkyl quaternary ammonium salt and an amino acid compound.

[0018] Preferably, the weight ratio of tetraalkyl quaternary ammonium salt to water is 0.5-1:100.

[0019] Preferably, the tetraalkyl quaternary ammonium salt is selected from one or more of tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium fluoride, and tetrapentylammonium bromide.

[0020] Preferably, the weight ratio of the amino acid compound to water is 0.01-0.1:100.

[0021] Preferably, the amino acid compound is selected from one or more of 2-bromophenylalanine, 2-chlorophenylalanine, 3-fluorophenylalanine, 4-aminohippuric acid, and N-ethylglycine.

[0022] Preferably, the weight ratio of stabilizer to water is 0.01-0.05:100.

[0023] Preferably, the stabilizer is selected from one or more of polydimethylsiloxane, aminopropyl-terminated polydimethylsiloxane, hydroxyl-terminated polydimethylsiloxane, and hexamethylcyclotrisiloxane.

[0024] A second aspect of the present invention provides the application of the aforementioned system for storing carbon dioxide in the hydrate method for storing and transporting carbon dioxide.

[0025] A third aspect of the present invention provides a method for storing and transporting carbon dioxide, the method comprising: contacting carbon dioxide with the aforementioned carbon dioxide storage system under hydrate formation conditions.

[0026] Preferably, the hydrate formation conditions include a temperature of 273.15-283.15 K and a pressure of 1-5 MPa.

[0027] The system for storing carbon dioxide described in this invention has the advantages of fast CO2 hydrate formation rate and high gas storage capacity, and is easy to operate and has excellent environmental performance. It has good application prospects in the field of CO2 capture and storage using the hydrate method. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the high-pressure fully transparent sapphire reactor evaluation device used in this invention;

[0029] Figure 2 This is a schematic diagram showing the trend of CO2 hydrate storage capacity changes in Example 1, Comparative Example 1, and Comparative Example 2.

[0030] Figure 3 This is a macroscopic morphology diagram of CO2 hydrates generated in the final system during performance evaluation in Example 1;

[0031] Figure 4 This is a macroscopic morphology diagram of CO2 hydrates generated in the final system during the performance evaluation in Comparative Example 1;

[0032] Figure 5 This is a macroscopic morphology diagram of the CO2 hydrates generated in the final system during the performance evaluation in Comparative Example 2.

[0033] Explanation of reference numerals in the attached figures

[0034] 1-Gas cylinder; 2, 3, 6, 8, 16-Stop valve; 4-High and low temperature test chamber; 5-Buffer vessel; 7-Three-way valve; 9-Exhaust port; 10-Fixing bolt; 11-Fixing rod; 12-High pressure sapphire vessel; 13-Magnet; 14-Magnetic ring; 15-Reaction liquid; 17-Drain port; 18-Automatic data acquisition system; 19-First pressure sensor; 20-Second pressure sensor; 21-Temperature sensor. Detailed Implementation

[0035] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0036] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0037] In one aspect, the present invention provides a system for storing carbon dioxide, the system containing water, a perfluorinated compound, and a CO2 hydrate promoter;

[0038] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 50-90% of the total volume.

[0039] The CO2 hydrate promoter contains emulsifiers, generation enhancers, and stabilizers.

[0040] This invention utilizes the hydrate slurry principle to enhance the nucleation and growth process of CO2 hydrates, thereby increasing the hydrate formation rate and gas storage capacity. The system contains a large volume of organic liquid (perfluorinated compounds), and the presence of emulsifiers causes the aqueous phase to disperse in the organic liquid as droplets. After the hydrate particles appear, they are dispersed as microparticles in the organic liquid phase, thus enhancing the overall nucleation and growth rate of the hydrate particles.

[0041] In a specific embodiment, the total volume of water and perfluorinated compounds is 100%, and the percentage of perfluorinated compounds can be 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90%.

[0042] In this invention, perfluorinated compounds not only have hydrophobic properties, but also have a large absorption and dissolution capacity for CO2 molecules, which can promote the diffusion of CO2 molecules in the liquid phase.

[0043] In a preferred embodiment, the perfluorinated compound is selected from one or more of perfluorohexanone, methyl perfluorodecanoate, ethyl perfluoropentanone, perfluoropropyl vinyl ether, and perfluoro(2-butyltetrahydrofuran).

[0044] To further improve the CO2 hydrate formation rate and gas storage capacity, a CO2 hydrate promoter is added to the system described in this invention. This CO2 hydrate promoter contains an emulsifier, a formation enhancer, and a stabilizer. The emulsifier disperses the aqueous phase in the organic liquid phase as droplets, increasing the specific surface area of ​​the CO2 hydrate during the nucleation process, thereby shortening the hydrate formation induction time. The formation enhancer primarily promotes rapid nucleation and growth of the CO2 hydrate. The stabilizer maintains the orderly and stable process of CO2 hydrate formation and decomposition, preventing the generation of large amounts of bubbles during hydrate formation and decomposition, which could lead to ineffective recovery of stored CO2.

[0045] In a preferred embodiment, the weight ratio of emulsifier to water is 0.01-0.1:100. Specifically, it can be 0.01:100, 0.02:100, 0.03:100, 0.04:100, 0.05:100, 0.06:100, 0.07:100, 0.08:100, 0.09:100, or 0.1:100.

[0046] In a preferred embodiment, the emulsifier is an anionic surfactant or an amphoteric surfactant.

[0047] More preferably, the emulsifier is composed of anionic surfactant and amphoteric surfactant in a weight ratio of 1:0.1-10. Specifically, the weight ratio of anionic surfactant to amphoteric surfactant can be 1:0.1, 1:0.2, 1:0.3, 1:0.5, 1:0.7, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10.

[0048] In a preferred embodiment, the anionic surfactant is selected from one or more of diethanolamine dodecyl sulfate, triethanolamine dodecyl sulfate, and sodium polyoxyethylene dodecyl ether sulfate.

[0049] In a preferred embodiment, the zwitterionic surfactant is a betaine-type zwitterionic surfactant.

[0050] In a preferred embodiment, the betaine-type zwitterionic surfactant is selected from one or more of dodecyl dimethyl betaine, 3-sulfopropyltetradecyl dimethyl betaine, 3-sulfopropylhexadecyl dimethyl betaine, lauramide propyl betaine, and cocamidopropyl betaine.

[0051] In a preferred embodiment, the generation enhancer mainly serves to promote the rapid nucleation and growth rate of CO2 hydrates, and is composed of a thermodynamic promoting component (tetraalkyl quaternary ammonium salt) and a kinetic promoting component (amino acid compounds).

[0052] In a preferred embodiment, the weight ratio of the tetraalkyl quaternary ammonium salt to water is 0.5-1:100. Specifically, it can be 0.5:100, 0.6:100, 0.7:100, 0.8:100, 0.9:100, or 1:100.

[0053] In a preferred embodiment, the tetraalkyl quaternary ammonium salt is selected from one or more of tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium fluoride, and tetrapentylammonium bromide.

[0054] In a preferred embodiment, the weight ratio of the amino acid compound to water is 0.01-0.1:100. Specifically, it can be 0.01:100, 0.02:100, 0.03:100, 0.04:100, 0.05:100, 0.06:100, 0.07:100, 0.08:100, 0.09:100, or 0.1:100.

[0055] In a preferred embodiment, the amino acid compound is selected from one or more of 2-bromophenylalanine, 2-chlorophenylalanine, 3-fluorophenylalanine, 4-aminohippuric acid, and N-ethylglycine.

[0056] In a preferred embodiment, the weight ratio of stabilizer to water is 0.01-0.05:100. Specifically, it can be 0.01:100, 0.02:100, 0.03:100, 0.04:100, or 0.05:100.

[0057] In a preferred embodiment, the stabilizer is selected from one or more of polydimethylsiloxane, aminopropyl-terminated polydimethylsiloxane, hydroxyl-terminated polydimethylsiloxane, and hexamethylcyclotrisiloxane.

[0058] A second aspect of the present invention provides the application of the aforementioned system for storing carbon dioxide in the hydrate method for storing and transporting carbon dioxide.

[0059] The carbon dioxide storage system described in this invention can produce CO2 hydrates upon contact with carbon dioxide under hydrate formation conditions, and it features a rapid hydrate formation rate and a large gas storage capacity. It has high application value in the hydrate-based storage and transportation of carbon dioxide.

[0060] A third aspect of the present invention provides a method for storing and transporting carbon dioxide, the method comprising: contacting carbon dioxide with the aforementioned carbon dioxide storage system under hydrate formation conditions.

[0061] Preferably, the hydrate formation conditions include a temperature of 273.15-283.15 K and a pressure of 1-5 MPa. Specifically, the temperature can be 273.15 K, 274.15 K, 275.15 K, 276.15 K, 277.15 K, 278.15 K, 279.15 K, 280.15 K, 281.15 K, 282.15 K, or 283.15 K; and the pressure can be 1 MPa, 2 MPa, 3 MPa, 4 MPa, or 5 MPa.

[0062] In this invention, unless otherwise specified, all pressures referred to are gauge pressures.

[0063] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited thereto.

[0064] In the following examples and comparative examples, a high-pressure, fully transparent sapphire reactor evaluation device was used for performance evaluation, in conjunction with reference to [reference needed]. Figure 1 The main components include a sapphire reactor body 12, a buffer vessel 5, a magnetic stirring system (magnet 13 and magnetic ring 14), a high and low temperature test chamber 4, a temperature sensor 21, a first pressure sensor 19, a second pressure sensor 20, and an automatic data acquisition system 18. The maximum working volume of the high-pressure sapphire reactor is 50 cm³. 3 The maximum working pressure is 20MPa, and the working temperature range is 183K~423K.

[0065] The specific steps for the performance evaluation experiment using the aforementioned high-pressure, fully transparent sapphire reactor are as follows:

[0066] (1) After cleaning the entire experimental system, place the reaction liquid (i.e. the system for storing CO2 provided in the examples and comparative examples) in the sapphire reactor, evacuate the system, and purge it with experimental gas more than 3 times.

[0067] (2) Set the system temperature to the experimental temperature. When the temperature inside the reactor reaches the preset value and remains stable for 2.0 hours, introduce a certain amount of experimental gas to make the system reach dissolution equilibrium (the pressure of the introduced gas is less than the hydrate equilibrium pressure at this temperature).

[0068] (3) Introduce experimental gas to the experimental pressure, close the gas inlet valve, and turn on the stirrer. The stirring speed remains constant throughout the entire experimental process. Observe the changes in the macroscopic morphology of the system during the experiment and record it online with a video recorder. The system temperature, pressure and reaction time are collected online and saved in the automatic data acquisition system.

[0069] (4) When white hydrate particles appear in the system, record the time at this time as the hydrate induction time;

[0070] (5) Continue the experiment and observe the evolution of the macroscopic morphology of hydrates in the system after the appearance of hydrate particles in real time; at the same time, record the temperature and pressure data continuously for 120 minutes from the time the hydrate particles appear (i.e. from the induction time).

[0071] (6) As hydrates continue to form, after the system pressure stabilizes and is maintained for 4.0 h, the system temperature is adjusted to 303 K. After the gas hydrates in the reactor are completely decomposed, the gas is vented and the liquid is drained, and the next group of experiments is restarted.

[0072] The steps for calculating CO2 storage capacity are as follows:

[0073] The molar amount of gas used to generate CO2 hydrate between t0 and t1 is determined by formula (1):

[0074]

[0075] Where P, V, T, and Z are the system pressure, gas phase volume, experimental temperature, and compressibility factor at the corresponding time points, and R is Avogadro's constant; t0 is the time corresponding to the initial appearance of hydrate particles in the system (induction time), and t1 is the time of the growth stage after the appearance of hydrate particles.

[0076] The compressibility factor Z mentioned in this invention is calculated using the Peng-Robinson equation of state, as shown in formula (2):

[0077] Z 3 -(1-B)Z 2 +(A-2B-3B 2 )Z-(AB-B 2 -B 3 )=0 (2)

[0078]

[0079]

[0080] a(T)=a c ·α(T)=0.45724R 2 T c 2 / P c ·α(T)

[0081]

[0082]

[0083] k=0.3746+1.54226ω-0.26992ω 2

[0084] Among them, T c P c ω and ω represent the critical temperature, critical pressure, and eccentricity factor of the experimental gas, respectively.

[0085] Therefore, the amount of CO2 hydrate stored at time t1 is calculated using formula (3):

[0086]

[0087] Among them, SC t This refers to the gas storage capacity of CO2 hydrate. MW represents the initial molar mass of the aqueous phase in the system. H2O and ρ H2O For the molar mass and density of water, MW Hydrate and ρ Hydrate Here, MW represents the molar mass and density of CO2 hydrate. Hydrate and ρ Hydrate Take 170 g / mol and 1.117 g / cm³ respectively. 3 .

[0088] The gas used in all the comparative examples and embodiments below is CO2 gas with a purity of 99.9%.

[0089] Example 1

[0090] This embodiment provides a system for storing CO2, which is obtained by mixing 5 mL of pure water, 5 mL of perfluorohexanone and a CO2 hydrate promoter;

[0091] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 50%;

[0092] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0093] The emulsifier is composed of diethanolamine dodecyl sulfate and dodecyl dimethyl betaine in a weight ratio of 1:1, and the weight ratio of the emulsifier to water is 0.05:100.

[0094] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium bromide and 2-bromophenylalanine, wherein the weight ratio of tetrabutylammonium bromide to water is 0.75:100, and the weight ratio of 2-bromophenylalanine to water is 0.05:100.

[0095] The stabilizer is polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0096] This embodiment uses, as follows: Figure 1 The high-pressure reactor shown was used for performance evaluation at an experimental temperature of 274.15 K and an experimental pressure of 3.0 MPa. Details of the change in CO2 hydrate storage capacity after the appearance of hydrate particles within the system are provided below. Figure 2 The induction time is detailed in Table 1. The gas storage capacity at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1. The macroscopic morphology of the final CO2 hydrate formed in the system is as follows: Figure 3 As shown, it is a viscous slurry.

[0097] Example 2

[0098] This embodiment provides a system for storing CO2, which is obtained by mixing 5 mL of pure water, 5 mL of perfluorohexanone and a CO2 hydrate promoter;

[0099] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 50%;

[0100] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0101] The emulsifier is composed of triethanolamine dodecyl sulfate and dodecyl dimethyl betaine in a weight ratio of 1:1, and the weight ratio of the emulsifier to water is 0.075:100.

[0102] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium bromide and 4-aminohippuric acid, wherein the weight ratio of tetrabutylammonium bromide to water is 0.75:100, and the weight ratio of 4-aminohippuric acid to water is 0.075:100.

[0103] The stabilizer is polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0104] This embodiment uses, as follows: Figure 1 The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0105] Example 3

[0106] This embodiment provides a system for storing CO2, which is obtained by mixing 5 mL of pure water, 5 mL of perfluorohexanone and a CO2 hydrate promoter;

[0107] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 50%;

[0108] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0109] The emulsifier is composed of triethanolamine dodecyl sulfate and lauramide propyl betaine in a weight ratio of 1:1, and the weight ratio of the emulsifier to water is 0.05:100.

[0110] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium chloride and 4-aminohippuric acid, wherein the weight ratio of tetrabutylammonium chloride to water is 0.75:100, and the weight ratio of 4-aminohippuric acid to water is 0.05:100.

[0111] The stabilizer is polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0112] This embodiment uses, as follows: Figure 1 The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0113] Example 4

[0114] This embodiment provides a system for storing CO2, which is obtained by mixing 5 mL of pure water, 2.5 mL of perfluorohexanone, 2.5 mL of ethyl perfluoropentanone, and a CO2 hydrate promoter.

[0115] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 50%;

[0116] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0117] The emulsifier is composed of triethanolamine dodecyl sulfate and lauramide propyl betaine in a mass ratio of 1:1, and the weight ratio of the emulsifier to water is 0.05:100.

[0118] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium chloride and 2-chlorophenylalanine, wherein the weight ratio of tetrabutylammonium bromide to water is 0.65:100, and the weight ratio of 2-chlorophenylalanine to water is 0.075:100.

[0119] The stabilizer is aminopropyl-terminated polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0120] This embodiment uses, as follows: Figure 1 The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0121] Example 5

[0122] This embodiment provides a system for storing CO2, which is obtained by mixing 5 mL of pure water, 2 mL of perfluorohexanone, 3 mL of perfluorinated (2-butyltetrahydrofuran) and a CO2 hydrate promoter;

[0123] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 50%;

[0124] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0125] The emulsifier is composed of diethanolamine dodecyl sulfate and dodecyl dimethyl betaine in a weight ratio of 1:1, and the weight ratio of the emulsifier to water is 0.075:100.

[0126] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium bromide and 2-bromophenylalanine, wherein the weight ratio of tetrabutylammonium bromide to water is 0.8:100, and the weight ratio of 2-bromophenylalanine to water is 0.025:100.

[0127] The stabilizer is polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0128] This embodiment uses, as follows: Figure 1 The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0129] Example 6

[0130] This embodiment provides a system for storing CO2, which is obtained by mixing 3 mL of pure water, 7 mL of perfluorohexanone, and a CO2 hydrate promoter;

[0131] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 70%;

[0132] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0133] The emulsifier is composed of diethanolamine dodecyl sulfate and dodecyl dimethyl betaine in a weight ratio of 1:1, and the weight ratio of the emulsifier to water is 0.05:100.

[0134] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium bromide and 2-bromophenylalanine, wherein the weight ratio of the amount of tetrabutylammonium bromide added to the amount of water is 0.75:100, and the weight ratio of the amount of 2-bromophenylalanine to the amount of water is 0.05:100.

[0135] The stabilizer is polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0136] This embodiment uses, as follows: Figure 1 The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0137] Example 7

[0138] This embodiment provides a system for storing CO2, which is obtained by mixing 3 mL of pure water, 7 mL of perfluorohexanone and a CO2 hydrate promoter;

[0139] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 70%;

[0140] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0141] The emulsifier is composed of triethanolamine dodecyl sulfate and dodecyl dimethyl betaine in a weight ratio of 1:1, and the weight ratio of the emulsifier to water is 0.075:100.

[0142] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium bromide and 4-aminohippuric acid, wherein the weight ratio of tetrabutylammonium bromide to water is 0.75:100, and the weight ratio of 4-aminohippuric acid to water is 0.075:100.

[0143] The stabilizer is polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0144] This embodiment uses, as follows: Figure 1 The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0145] Example 8

[0146] This embodiment provides a system for storing CO2, which is obtained by mixing 3 mL of pure water, 7 mL of perfluorohexanone and a CO2 hydrate promoter;

[0147] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 70%;

[0148] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0149] The emulsifier is composed of triethanolamine dodecyl sulfate and lauramide propyl betaine in a mass ratio of 1:1, and the weight ratio of the emulsifier to water is 0.05:100.

[0150] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium chloride and 4-aminohippuric acid, wherein the weight ratio of tetrabutylammonium chloride to water is 0.75:100, and the weight ratio of 4-aminohippuric acid to water is 0.05:100.

[0151] The stabilizer is polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0152] This embodiment uses, as follows: Figure 1 The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0153] Example 9

[0154] This embodiment provides a system for storing CO2, which is obtained by mixing 1 mL of pure water, 9 mL of perfluorohexanone and a CO2 hydrate promoter;

[0155] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 90%;

[0156] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0157] The emulsifier is composed of diethanolamine dodecyl sulfate and dodecyl dimethyl betaine in a mass ratio of 1:1, and the weight ratio of the emulsifier to water is 0.05:100.

[0158] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium bromide and 2-bromophenylalanine, wherein the weight ratio of tetrabutylammonium bromide to water is 0.75:100, and the weight ratio of 2-bromophenylalanine to water is 0.05:100.

[0159] The stabilizer is polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0160] This embodiment uses, as follows: Figure 1 The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0161] Example 10

[0162] This embodiment provides a system for storing CO2, which is obtained by mixing 1 mL of pure water, 9 mL of perfluorohexanone and CO2 hydrate promoter.

[0163] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 90%;

[0164] The specific composition and dosage of the composite CO2 hydrate promoter are as follows:

[0165] The emulsifier is composed of triethanolamine dodecyl sulfate and dodecyl dimethyl betaine in a weight ratio of 1:1, and the weight ratio of the emulsifier to water is 0.075:100.

[0166] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium bromide and 4-aminohippuric acid, wherein the weight ratio of tetrabutylammonium bromide to water is 0.75:100, and the weight ratio of 4-aminohippuric acid to water is 0.075:100.

[0167] The stabilizer is polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0168] This embodiment uses, as follows: Figure 1 The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0169] Example 11

[0170] This embodiment provides a system for storing CO2, which is obtained by mixing 1 mL of pure water, 9 mL of perfluorohexanone and a CO2 hydrate promoter;

[0171] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 90%;

[0172] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0173] The emulsifier is composed of triethanolamine dodecyl sulfate and lauramide propyl betaine in a weight ratio of 1:1, and the weight ratio of the emulsifier to water is 0.05:100.

[0174] A fortifying agent is generated, wherein the fortifying agent is composed of tetrabutylammonium chloride and 4-aminohippuric acid, wherein the weight ratio of tetrabutylammonium chloride to water is 0.75:100, and the weight ratio of 4-aminohippuric acid to water is 0.05:100.

[0175] The stabilizer is polydimethylsiloxane, and the weight ratio of the stabilizer to water is 0.025:100.

[0176] This embodiment uses, as follows: Figure 1The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0177] Comparative Example 1

[0178] This comparative example provides a system for storing CO2, consisting of 10 mL of pure water.

[0179] This comparative example adopts the following... Figure 1 The high-pressure reactor shown was used for performance evaluation at an experimental temperature of 274.15 K and an experimental pressure of 3.0 MPa. Details of the change in CO2 hydrate storage capacity after the appearance of hydrate particles within the system are provided below. Figure 2 The induction time is detailed in Table 1. The gas storage capacity at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1. The macroscopic morphology of the final CO2 hydrate formed in the system is as follows: Figure 4 As shown, a large number of clumps appeared.

[0180] Comparative Example 2

[0181] This comparative example provides a system for storing CO2, which is obtained by mixing 5 mL of pure water and 5 mL of perfluorohexanone, with the total volume of water and perfluorinated compounds being 100% and the perfluorinated compounds accounting for 50%.

[0182] This comparative example adopts the following... Figure 1 The high-pressure reactor shown was used for performance evaluation at an experimental temperature of 274.15 K and an experimental pressure of 3.0 MPa. Details of the change in CO2 hydrate storage capacity after the appearance of hydrate particles within the system are provided below. Figure 2 The induction time is detailed in Table 1. The gas storage capacity at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1. The macroscopic morphology of the final CO2 hydrate formed in the system is as follows: Figure 5 As shown, a large number of blocky objects also appeared.

[0183] Comparative Example 3

[0184] This comparative example provides a system for storing CO2, which is obtained by mixing 8.5 mL of pure water and 1.5 mL of perfluorohexanone, wherein the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 15%.

[0185] This comparative example adopts the following... Figure 1The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0186] Comparative Example 4

[0187] This comparative example provides a system for storing CO2, consisting of 8.5 mL of pure water, 1.5 mL of perfluorohexanone, and a CO2 hydrate promoter;

[0188] Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 15%.

[0189] The specific composition and dosage of the CO2 hydrate promoter are as follows:

[0190] The emulsifier is composed of diethanolamine dodecyl sulfate and dodecyl dimethyl betaine in a weight ratio of 1:1, and the weight ratio of emulsifier to water is 0.05:100.

[0191] The fortifying agent is composed of tetrabutylammonium bromide and 2-bromophenylalanine, with the weight ratio of tetrabutylammonium bromide to water being 0.75:100 and the weight ratio of 2-bromophenylalanine to water being 0.05:100.

[0192] The stabilizer is polydimethylsiloxane, and the weight ratio of stabilizer to water is 0.025:100.

[0193] This comparative example adopts the following... Figure 1 The high-pressure reactor shown was used for performance evaluation. The experimental temperature was 274.15 K and the experimental pressure was 3.0 MPa. The induction time is detailed in Table 1. The gas storage volume at 20 min and 120 min, starting from the appearance of hydrates, is detailed in Table 1.

[0194] Table 1

[0195]

[0196] As shown in Table 1, under hydrate formation conditions, contacting CO2 with the CO2 storage system described in this invention can significantly shorten the hydrate induction time and increase the gas storage capacity.

[0197] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A system for storing carbon dioxide, characterized in that, The system contains water, perfluorinated compounds, and CO2 hydrate promoters; Of which, the total volume of water and perfluorinated compounds is 100%, and the perfluorinated compounds account for 50-90% of the total volume. The CO2 hydrate promoter contains emulsifiers, generation enhancers, and stabilizers; The perfluorinated compounds are selected from one or more of perfluorohexanone, methyl perfluorodecanoate, ethyl perfluoropentanone, perfluoropropyl vinyl ether, and perfluoro(2-butyltetrahydrofuran); The emulsifier is an anionic surfactant and an amphoteric surfactant, and the amphoteric surfactant is a betaine-type amphoteric surfactant. The strengthening agent is a tetraalkyl quaternary ammonium salt and an amino acid compound; The stabilizer is selected from one or more of polydimethylsiloxane, aminopropyl-terminated polydimethylsiloxane, hydroxyl-terminated polydimethylsiloxane, and hexamethylcyclotrisiloxane.

2. The system for storing carbon dioxide according to claim 1, characterized in that, The weight ratio of emulsifier to water is 0.01-0.1:

100.

3. The system for storing carbon dioxide according to claim 1, characterized in that, The weight ratio of the anionic surfactant to the amphoteric surfactant is 1:0.1-10.

4. The system for storing carbon dioxide according to claim 3, characterized in that, The anionic surfactant is selected from one or more of diethanolamine dodecyl sulfate, triethanolamine dodecyl sulfate, and sodium polyoxyethylene dodecyl ether sulfate.

5. The system for storing carbon dioxide according to claim 1, characterized in that, The betaine-type zwitterionic surfactant is selected from one or more of dodecyl dimethyl betaine, 3-sulfopropyltetradecyl dimethyl betaine, 3-sulfopropylhexadecyl dimethyl betaine, lauramide propyl betaine, and cocamidopropyl betaine.

6. The system for storing carbon dioxide according to claim 1, characterized in that, The weight ratio of tetraalkyl quaternary ammonium salt to water is 0.5-1:

100.

7. The system for storing carbon dioxide according to claim 1 or 6, characterized in that, Tetraalkyl quaternary ammonium salts are selected from one or more of tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium fluoride, and tetrapentylammonium bromide.

8. The system for storing carbon dioxide according to claim 1, characterized in that, The weight ratio of amino acid compounds to water is 0.01-0.1:

100.

9. The system for storing carbon dioxide according to claim 1, characterized in that, The amino acid compounds are selected from one or more of 2-bromophenylalanine, 2-chlorophenylalanine, 3-fluorophenylalanine, 4-aminohippuric acid, and N-ethylglycine.

10. The system for storing carbon dioxide according to claim 1, characterized in that, The weight ratio of stabilizer to water is 0.01-0.05:

100.

11. The application of the system for storing carbon dioxide according to any one of claims 1-10 in the hydrate method for storing and transporting carbon dioxide.

12. A method for storing and transporting carbon dioxide, characterized in that, The method comprises: contacting carbon dioxide with the carbon dioxide storage system according to any one of claims 1-10 under hydrate formation conditions.

13. The method according to claim 12, characterized in that, The conditions for hydrate formation include a temperature of 273.15-283.15 K and a pressure of 1-5 MPa.

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