An ionic liquid graphene oxide composite material, its preparation method and application

Abstract

The present invention belongs to the technical field of the preparation of graphene oxide materials, and particularly relates to an ionic liquid graphene oxide composite material, a preparation method thereof and an application. The preparation method of the ionic liquid graphene oxide composite material provided by the present invention comprises the following steps: S1, reacting a polyethylenepolyamine with an organic anion precursor to obtain a target ionic liquid; S2, dispersing graphene oxide in water, adding the above-mentioned target ionic liquid, stirring, and freeze-drying to obtain the ionic liquid graphene oxide composite material. By chemically bonding an ionic liquid with multiple active sites to graphene oxide to form an ionic liquid graphene oxide composite material, the present invention not only has active sites for anions, but also has active sites for cations, greatly increasing the carbon dioxide adsorption amount.

Description

Technical Field

[0001] The present invention belongs to the technical field of the preparation of graphene oxide materials, and particularly relates to an ionic liquid graphene oxide composite material, a preparation method thereof and an application thereof. Background Art

[0002] Carbon dioxide is the main combustion product of fossil fuels and is the main cause of environmental changes such as rising atmospheric temperatures, increasing ocean acidity, and melting glaciers. Among them, carbon dioxide gas generated by human industrial activities accounts for the largest proportion in global greenhouse gases. In order to slow down the process of global warming, it is a requirement of the current environmental situation for new materials to be able to capture carbon dioxide existing in the atmosphere and reduce its concentration in the atmosphere.

[0003] In the prior art, a preparation method and an application of a flexible bulk amine-modified three-dimensional graphene mesoporous material are disclosed. Among them, the preparation method of this material is as follows: Step 1, ultrasonically disperse an aqueous solution of graphene oxide, and then adjust the pH value with an aqueous solution of sodium hydroxide to obtain a graphene oxide dispersion; Step 2, mix an aqueous solution of high amine with the graphene oxide dispersion obtained in Step 1, stir well and ultrasonically to obtain a mixture; Step 3, put the mixture obtained in Step 2 into a mold and place it in an incubator for heat preservation and static settlement to form a hydrogel; Step 4, demold the hydrogel formed in Step 3, soak it in deionized water and then perform freeze-drying to obtain a flexible bulk amine-modified three-dimensional graphene mesoporous material.

[0004] However, the application of the flexible bulk amine-modified three-dimensional graphene mesoporous material disclosed in the prior art to the absorption of carbon dioxide is achieved by the chemical reaction between an organic amine and carbon dioxide. The organic amine and carbon dioxide are bonded by chemical bonds, and it is difficult to desorb after adsorption and regeneration needs to be carried out at high temperature, which will cause volatilization loss of the organic amine and affect the adsorption performance of the regenerated material. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect in the prior art that the active sites for adsorbing carbon dioxide in graphene oxide materials cannot be increased, and thus to provide an ionic liquid graphene oxide composite material, a preparation method thereof and an application thereof.

[0006] To this end, the present invention provides the following technical solutions.

[0007] The present invention provides a preparation method of an ionic liquid graphene oxide composite material, comprising the following steps:

[0008] S1, react polyethylenepolyamine with an organic anion precursor to obtain a target ionic liquid;

[0009] S2. Disperse graphene oxide in water, add the above-mentioned target ionic liquid, stir, and freeze-dry to obtain the ionic liquid graphene oxide composite material.

[0010] Typical non-limiting examples of the organic anion precursor include at least one of dimethylhydantoin, imidazole, hydroxypyridine, 1,2,4-triazole, and pyridine. It can also select an organic anion that has active sites for binding to CO2 and a relatively small acidity coefficient pKa as the raw material.

[0011] For step S1, the specific reaction method can be selected according to the acidity coefficient pKa of the organic anion precursor. For organic anion precursors with pKa ≤ 3, such as triazole (pKa = 1.17) and hydroxypyridine (pKa = 0.75), the direct reaction method can be used, that is, directly react the organic anion precursor with polyethylenepolyamine to obtain the target ionic liquid. For organic anion precursors with pKa > 3, first convert polyethylenepolyamine into a basic ionic liquid and then react it with the organic anion precursor, which can improve the reaction efficiency.

[0012] Optionally, in step S2, the molar ratio of graphene oxide to the target ionic liquid is (1 - 3):1;

[0013] And / or, the stirring time is 12 - 24 h.

[0014] Optionally, before reacting with the organic anion precursor in step S1, it further includes the steps of preparing a polyethylenepolyamine ionic liquid and obtaining a basic polyethylenepolyamine ionic liquid through ion exchange.

[0015] Optionally, step S1 includes:

[0016] Drop the organic anion precursor into polyethylenepolyamine under stirring conditions at 20 - 25 °C and react for 24 - 36 h to obtain the target ionic liquid;

[0017] Or, drop the acid solution into polyethylenepolyamine under stirring conditions at 0 - 5 °C, heat up to 20 - 25 °C and react for 4 - 8 h to generate a polyethylenepolyamine ionic liquid, obtain a basic polyethylenepolyamine ionic liquid through ion exchange, and react with the organic anion precursor at 40 - 50 °C for 24 - 36 h to obtain the target ionic liquid.

[0018] Specifically, taking [HDETA][Tz] as an example, 0.5 mol of Tz (1,2,4-triazole) was mixed with 50 mL of ethanol, and then an equimolar amount of DETA (diethylenetriamine, with a strict molar ratio of 1:1) was added using a constant-pressure funnel. The mixture was stirred at 3 °C for 24 h. After the reaction, the solvent was removed by heating the mixed solution at 55 °C for 4 h using a rotary evaporator. The sample was dried under vacuum at 55 °C for 40 h to obtain the target ionic liquid [HDETA][Tz].

[0019] Optionally, the acid solution is at least one of hydrochloric acid and hydrobromic acid; the mass concentration of the acid solution is 36 - 48%;

[0020] And / or, the polyethylenepolyamine is at least one of diethylenetriamine, triethylenetetramine, and tetraethylenepentamine;

[0021] And / or, the molar ratio of the acid solution to the polyethylenepolyamine is (1 - 3):1.

[0022] Optionally, the ion exchange includes the following steps:

[0023] The basic anion exchange resin was soaked in saturated brine with a volume 2 - 3 times that of the resin for 18 - 20 h, washed with water, soaked in an HCl solution with a mass fraction of 5 - 8% for 4 - 8 h, washed with water until neutral, then soaked in an NaOH solution with a mass fraction of 2 - 4% for 4 - 8 h, washed with water until neutral, packed into a column, and the column was exchanged into a small molecule alcohol column using small molecule alcohol;

[0024] The polyethylenepolyamine ionic liquid was dispersed in a small molecule alcohol solvent, and ion exchange was carried out on the small molecule alcohol column;

[0025] Optionally, the mass ratio of the polyethylenepolyamine ionic liquid to the small molecule alcohol is 1:(2 - 3);

[0026] Typical non-limiting small molecule alcohols are at least one of methanol and ethanol, and other liquids that can dissolve the ionic liquid and are easily removed by rotary evaporation can also be selected.

[0027] The present invention provides an ionic liquid graphene oxide composite material prepared by the above method.

[0028] The present invention also provides an application of the ionic liquid graphene oxide composite material in carbon dioxide adsorption.

[0029] Optionally, the adsorption temperature is 40 - 50 °C, and the adsorption pressure is 0.1 - 0.2 MPa;

[0030] Optionally, the regeneration temperature is 80 - 90 °C.

[0031] Specifically, the process for preparing the ionic liquid graphene oxide composite material by the stepwise method provided by the present invention is roughly as follows:

[0032]

[0033] Among them, represents the structure of graphene oxide that is not drawn;

[0034] The specific steps are as follows:

[0035] 1. Add diethylenetriamine (triethylenetetramine or tetraethylenepentamine) to a three-necked flask and magnetically stir for 30 min under an ice-water bath condition; the purpose of this step is to lower the temperature of diethylenetriamine because the reaction between hydrochloric acid and diethylenetriamine is violent. Therefore, a reflux device also needs to be added above the reactor to ensure safety.

[0036] 2. Connect a serpentine condenser, and add hydrochloric acid dropwise to the three-necked flask through a constant pressure funnel. It takes about one hour to finish the dropping. This process is still completed under the condition of magnetic stirring in an ice-water bath; after the hydrochloric acid is dropped, raise the temperature to 25 °C and stir for 4 hours to generate the ionic liquid [HDETA][Cl].

[0037] 3. For IRA-900 anion exchange resin, first use saturated brine, and take an amount approximately equal to 2-3 times the volume of the resin to be treated. Immerse the resin in saturated brine for 18-20 h, then drain the brine and wash with water until the water is not yellow. Then treat it with 5% HCl, soak for about 4-8 h, drain the acid solution, wash with water until neutral, and then soak with 2%-4% NaOH solution for 4-8 h, drain the alkali solution, wash with water until neutral for activation. After activation, load it into a column and exchange the column with ethanol to form an ethanol column. IRA-900 anion exchange resin is first used with saturated brine, taking an amount approximately equal to 2-3 times the volume of the resin to be treated. Immerse the resin in saturated brine for 18-20 h, then drain the brine and wash with water until the water is not yellow. Then treat it with 5% HCl, soak for about 4-8 h, drain the acid solution, wash with water until neutral, and then soak with 2%-4% NaOH solution for 4-8 h, drain the alkali solution, wash with water until neutral for activation. After activation, load it into a column and exchange the column with ethanol to form an ethanol column.

[0038] 4. Ultrasonically dissolve [HDETA][Cl] to form a [HDETA][Cl] ethanol solution, and then load the [HDETA][Cl] ethanol solution onto the column for anion exchange to exchange the anion Cl - into OH - to obtain a [HDETA][OH] ethanol solution.

[0039] 5. Add dimethylhydantoin to a three-necked flask, and dropwise add the diethylenetriamine hydroxide ethanol solution to the three-necked flask at room temperature and react for 24 hours. Rotary evaporate at 50 °C to obtain the target ionic liquid [HDETA][Dhyd].

[0040] 6. Dissolve graphene oxide powder in deionized water and ultrasonically treat for 2 h to form a GO dispersion.

[0041] 7. Add ionic liquid [HDETA][Dhyd] to it, shake evenly (if there is no oscillator, shake it by hand), form a hydrogel (observe whether flocs are formed), stir for 24 h, and dry it in a freeze dryer to obtain the target material.

[0042] The technical solution of the present invention has the following advantages:

[0043] The preparation method of the ionic liquid graphene oxide composite material provided by the present invention includes the following steps: S1, reacting polyethylenepolyamine with an organic anion precursor to obtain a target ionic liquid; S2, dispersing graphene oxide in water, adding the above target ionic liquid, stirring, and freeze-drying to obtain the ionic liquid graphene oxide composite material. By chemically bonding the ionic liquid with multiple active sites to graphene oxide to form an ionic liquid graphene oxide composite material, not only the anion has active sites, but the cation also has active sites, greatly increasing the carbon dioxide adsorption amount; compared with the organic amine adsorption material, the carbamate formed during the process of the ionic liquid graphene oxide composite material provided by the present invention adsorbing carbon dioxide has a lower bond energy than that of the organic amine, the regeneration process is relatively easy, the recyclability is good, and the decomposition temperature of the ionic liquid is high, there will be no volatilization loss during the regeneration process, and the retention rate of the carbon dioxide adsorption amount during regeneration is high.

[0044] In addition, the ionic liquid graphene oxide composite material provided by the present invention improves the absorption rate without affecting the carbon dioxide absorption amount. This is because the viscosity of the pure ionic liquid increases after absorbing carbon dioxide, and the absorption rate will slow down. After loading the ionic liquid onto the graphene oxide material, the composite material has a typical quasi-two-dimensional spatial structure, and there are a large number of hydroxyl and carboxyl acidic active groups on its sheets, making it easier for gas to pass through the material. Specific embodiments

[0045] The following embodiments are provided to better understand the present invention further. They are not limited to the best implementation mode, and do not limit the content and protection scope of the present invention. Any product that is the same as or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior art features falls within the protection scope of the present invention.

[0046] For those not specifying specific experimental steps or conditions in the embodiments, the operations or conditions of the conventional experimental steps described in the literature in this field can be followed. For the reagents or instruments not specifying the manufacturer, they are all conventional reagent products that can be obtained through commercial purchase.

[0047] Example 1

[0048] This example provides a preparation method of an ionic liquid graphene oxide composite material, including the following steps:

[0049] 1. Add 10 g of diethylenetriamine into a three-necked flask and magnetically stir for 30 min under an ice-water bath condition;

[0050] 2. Connect a reflux condenser. Add 10 g of 38% hydrochloric acid dropwise into the three-necked flask through a constant pressure funnel over 1 h. This process is still completed under the condition of magnetic stirring in an ice-water bath. After the addition, raise the temperature to 25 °C and stir for 4 hours to generate ionic liquid A.

[0051] 3. Place 100 g of IRA-900 anion exchange resin in 200 ml of saturated brine and soak for 19 h, then drain the brine and wash with water until the water is no longer yellow. Then soak in 5% HCl by mass for about 6 h, drain the acid solution, and wash with water until neutral. Then soak in 3% NaOH solution by mass for 6 h, drain the alkali solution, and wash with water until neutral for activation and column packing. Exchange the column with ethanol to form an ethanol column.

[0052] 4. Ultrasonically dissolve ionic liquid A in 30 ml of ethanol, then load it onto the column for anion exchange, and exchange the anion Cl - to OH - to obtain an ionic liquid B solution.

[0053] 5. Add 26 g of dimethylhydantoin into a three-necked flask, and dropwise add ionic liquid B into the three-necked flask at room temperature. React at 25 °C for 24 h and rotary evaporate at 0 °C to obtain the target ionic liquid C.

[0054] 6. Dissolve 7 g of graphene oxide powder in 500 ml of deionized water and ultrasonically treat for 2 h to form a graphene oxide dispersion.

[0055] 7. Add 3 g of ionic liquid C thereto, mix and shake for 5 min, stir for 24 h, and perform freeze-drying for 48 h at a drying temperature of -80 °C and a pressure of 0.1 Pa to obtain an ionic graphene oxide composite material.

[0056] Example 2

[0057] This example provides a preparation method of an ionic graphene oxide composite material, including the following steps:

[0058] 1. Add 15 g of triethylenetetramine into a three-necked flask and magnetically stir for 30 min under an ice-water bath condition;

[0059] 2. Connect a reflux condenser. Add 20 g of 38% hydrochloric acid dropwise into the three-necked flask through a constant pressure funnel over 1 h. This process is still completed under the condition of magnetic stirring in an ice-water bath. After the addition, raise the temperature to 25 °C and stir for 4 hours to generate ionic liquid A.

[0060] 3. Place 100 g of IRA-900 anion exchange resin in 200 ml of saturated brine and soak for 19 h, then drain the brine, wash with water until the water is no longer yellow, then soak in 5% HCl by mass for about 6 h, drain the acid solution, and wash with water until neutral. Then soak in 3% NaOH solution by mass for 6 h, drain the alkali solution, and wash with water until neutral for activation and column packing, and exchange the column with ethanol to form an ethanol column.

[0061] 4. Ultrasonically dissolve ionic liquid A in ethanol, then load it onto the column for anion exchange, and exchange the anion Cl - with OH - to obtain an ionic liquid B solution.

[0062] 5. Add 13 g of dimethylhydantoin to a three-necked flask, and slowly add ionic liquid B dropwise to the three-necked flask at room temperature, react for 24 h, and rotary evaporate at 50 °C to obtain the target ionic liquid C.

[0063] 6. Dissolve 7 g of graphene oxide powder in 500 ml of deionized water and ultrasonicate for 2 h to form a graphene oxide dispersion.

[0064] 7. Add 3 g of ionic liquid C to it, mix and shake for 5 min, stir for 24 h, and perform freeze-drying for 48 h at a drying temperature of -80 °C and a pressure of 0.1 Pa to obtain an ionic graphene oxide composite material.

[0065] Example 3

[0066] This example provides a method for preparing an ionic graphene oxide composite material, including the following steps:

[0067] 1. Add 10 g of diethylenetriamine to a three-necked flask and magnetically stir for 30 min under an ice-water bath condition;

[0068] 2. Connect a snake-shaped condenser, and slowly add 10 g of 38% hydrochloric acid dropwise to the three-necked flask through a constant pressure funnel over 1 h. This process is still completed under the condition of magnetic stirring in an ice-water bath; after dropping, raise the temperature to 25 °C and stir for 4 h to generate ionic liquid A.

[0069] 3. Place 100 g of IRA-900 anion exchange resin in 200 ml of saturated brine and soak for 19 h, then drain the brine, wash with water until the water is no longer yellow, then soak in 5% HCl by mass for about 6 h, drain the acid solution, and wash with water until neutral. Then soak in 3% NaOH solution by mass for 6 h, drain the alkali solution, and wash with water until neutral for activation and column packing, and exchange the column with ethanol to form an ethanol column.

[0070] 4. Dissolve ionic liquid A in ethanol by ultrasonic treatment, and then perform anion exchange on the column to exchange the anion Cl - into OH - , to obtain an ionic liquid B solution.

[0071] 5. Add 7 g of imidazole to a three-necked flask, and slowly add ionic liquid B dropwise to the three-necked flask at room temperature. React for 24 h, and rotary evaporate at 50 °C to obtain the target ionic liquid C.

[0072] 6. Dissolve 7 g of graphene oxide powder in 500 ml of deionized water, and perform ultrasonic treatment for 2 h to form a graphene oxide dispersion.

[0073] 7. Add 3 g of ionic liquid C thereto, mix and shake for 5 min, stir for 24 h, and perform freeze-drying for 48 h. The drying temperature is -80 °C and the pressure is 0.1 Pa to obtain an ionic graphene oxide composite material.

[0074] Example 4

[0075] This example provides a method for preparing an ionic graphene oxide composite material, including the following steps:

[0076] 1. Add 10 g of diethylenetriamine to a three-necked flask, and perform magnetic stirring for 30 min under an ice-water bath condition;

[0077] 2. Connect a reflux condenser, and slowly add 10 g of 38% hydrochloric acid dropwise to the three-necked flask through a constant pressure funnel over 1 h. This process is still completed under magnetic stirring in an ice-water bath; after the addition, raise the temperature to 25 °C and stir for 4 h to generate ionic liquid A.

[0078] 3. Place 100 g of IRA-900 anion exchange resin in 200 ml of saturated brine and soak for 19 h, then drain the brine, wash with water until the water is colorless, then soak in 5% HCl by mass for about 6 h, drain the acid solution, and wash with water until neutral. Then soak in 3% NaOH solution by mass for 6 h, drain the alkali solution, and wash with water until neutral for activation and column packing, and exchange the column with ethanol to form an ethanol column.

[0079] 4. Dissolve ionic liquid A in ethanol by ultrasonic treatment, and then perform anion exchange on the column to exchange the anion Cl - into OH - , to obtain an ionic liquid B solution.

[0080] 5. Add 7 g of imidazole into a three-necked flask, and dropwise add ionic liquid B into the three-necked flask at room temperature. React for 24 h, and rotary evaporate at 50 °C to obtain the target ionic liquid C.

[0081] 6. Dissolve 5 g of graphene oxide powder in 500 ml of deionized water, and ultrasonicate for 2 h to form a graphene oxide dispersion.

[0082] 7. Add 5 g of ionic liquid C thereto, mix and shake for 5 min, stir for 24 h, and perform freeze-drying for 48 h at a drying temperature of -80 °C and a pressure of 0.1 Pa to obtain an ionic graphene oxide composite material.

[0083] Example 5

[0084] This example provides a preparation method of an ionic graphene oxide composite material, including the following steps:

[0085] 1. Mix 0.5 mol of Tz (1,2,4-triazole) with 50 mL of ethanol, and then add an equimolar amount of DETA (diethylenetriamine, molar ratio strictly according to 1:1) using a constant-pressure funnel. Stir at room temperature for 24 h. After the reaction, heat the mixed solution at 55 °C for 4 h using a rotary evaporator to remove the solvent. Dry the sample under vacuum at 55 °C for 40 h to obtain the target ionic liquid [HDETA][Tz].

[0086] 2. Dissolve 7 g of graphene oxide powder in 500 ml of deionized water, and ultrasonicate for 2 h to form a graphene oxide dispersion.

[0087] 3. Add 3 g of ionic liquid [HDETA][Tz] thereto, mix and shake for 5 min, stir for 24 h, and perform freeze-drying for 48 h at a drying temperature of -80 °C and a pressure of 0.1 Pa to obtain an ionic graphene oxide composite material.

[0088] Comparative Example 1

[0089] This comparative example provides a preparation method of an ionic graphene oxide composite material, including the following steps:

[0090] 1. Add 10 g of diethylenetriamine into a three-necked flask, and magnetically stir for 30 min under an ice-water bath condition;

[0091] 2. Connect a snake-shaped condenser, and dropwise add 10 g of hydrochloric acid with a concentration of 36 - 38% into the three-necked flask through a constant-pressure funnel over 1 h. This process is still completed under the condition of magnetic stirring in an ice-water bath; after dropping, raise the temperature to 25 °C and stir for 4 h to generate ionic liquid A.

[0092] 3. 100 g of The IRA-900 anion exchange resin was immersed in 200 ml of saturated brine for 19 h, then the brine was drained off and the resin was washed with water until the water was colorless. Then it was treated with 5% HCl and soaked for about 6 h. After draining off the acid solution, it was washed with water until neutral. Then it was soaked in 3% NaOH solution for 6 h, the alkaline solution was drained off, and it was washed with water until neutral. After activation and column packing, the column was exchanged with ethanol to form an ethanol column.

[0093] 4. The ionic liquid A was ultrasonically dissolved in 30 ml of ethanol, and then loaded onto the column for anion exchange to exchange the anion Cl - into OH - , obtaining an ionic liquid B solution.

[0094] 5. 7 g of graphene oxide powder was dissolved in 150 - 500 ml of deionized water and ultrasonically treated for 2 h to form a graphene oxide dispersion.

[0095] 6. 3 g of ionic liquid C was added thereto, and the mixture was shaken for 5 min and stirred for 24 h, followed by freeze-drying for 48 h at a drying temperature of -80 °C and a pressure of 0.1 Pa to obtain an ionic oxidized graphene composite material.

[0096] Test Example

[0097] For the ionic liquid oxidized graphene composite materials prepared in Examples 1 - 5 and Comparative Examples, the test methods for the carbon dioxide adsorption capacity and adsorption rate were as follows: 5 g of the composite material was added to a U-shaped tube with an inner diameter of 2.0 cm, and then the U-shaped tube was immersed 5 cm into a water bath at 40 °C. The standard uncertainty of the temperature under ideal conditions was ±0.1 °C. By adjusting the gas mass flowmeter, CO2 was bubbled into the absorption flask at a flow rate of 200 mL / min. Every 5 min, the absorption flask was disconnected from the CO2 supply end and weighed on an electronic balance with a precision of ±0.0001 g to measure the mass of CO2 absorbed by the ionic liquid until the mass of the U-shaped tube no longer changed, indicating that the composite material had reached saturation absorption.

[0098] CO2 desorption experiment: The material saturated with CO2 absorption was placed in a constant temperature water bath at 90 °C, and N2 was introduced at a flow rate of 100 mL / min controlled by a gas mass controller for desorption experiment by heating and purging. The mass of the absorption flask was weighed every 5 min until the mass of the U-shaped tube no longer changed, indicating complete desorption. The reduced mass of the U-shaped tube was the mass of the desorbed CO2.

[0099] The test method for the adsorption capacity after N recycles was to confirm the recyclability through five absorption and desorption experiments.

[0100] The test results are shown in Table 1.

[0101] Table 1:

[0102]

[0103]

[0104] As can be seen from Table 1, the absorption capacity will increase significantly after loading with ionic liquid. At the same time, the absorption equilibrium time of pure ionic liquid is about 60 minutes, while the absorption equilibrium time after loading is significantly shortened, improving the absorption rate. The adsorption capacity basically remains unchanged after the absorption and desorption cycle experiment.

[0105] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A preparation method of an ionic liquid graphene oxide composite material, characterized in that It includes the following steps: S1. React polyethylenepolyamine with an organic anion precursor to obtain a target ionic liquid; The organic anion precursor is dimethylhydantoin; S2. Disperse graphene oxide in water, add the above-mentioned target ionic liquid, stir, and freeze-dry to obtain the ionic liquid graphene oxide composite material.

2. The preparation method of the ionic liquid graphene oxide composite material according to claim 1, characterized in that, In step S2, the molar ratio of graphene oxide to the target ionic liquid is (1-3):1; And / or, the stirring time is 12-24 h.

3. The preparation method of the ionic liquid graphene oxide composite material according to claim 1 or 2, characterized in that Before reacting with the organic anion precursor in step S1, it further includes the steps of preparing a polyethylenepolyamine ionic liquid and obtaining a basic polyethylenepolyamine ionic liquid through ion exchange.

4. The preparation method of the ionic liquid graphene oxide composite material according to claim 3, wherein, Step S1 includes: Dropwise add an acid solution to polyethylenepolyamine under the conditions of 0-5 °C and stirring, raise the temperature to 20-25 °C and react for 4-8 h to generate a polyethylenepolyamine ionic liquid. After ion exchange, obtain a basic polyethylenepolyamine ionic liquid and react with the organic anion precursor at 40-50 °C for 24-36 h to obtain the target ionic liquid.

5. The preparation method of the ionic liquid graphene oxide composite material according to claim 4, wherein, The acid solution is at least one of hydrochloric acid and hydrobromic acid; and / or, the mass concentration of the acid solution is 36-48%; And / or, the polyethylenepolyamine is at least one of diethylenetriamine, triethylenetetramine, and tetraethylenepentamine; And / or, the molar ratio of the acid solution to polyethylenepolyamine is (1-3):

1.

6. The preparation method of the ionic liquid graphene oxide composite material according to claim 3, wherein, The ion exchange includes the following steps: Soak the basic anion exchange resin in saturated brine with a volume 2-3 times that of the resin for 18-20 h, wash with water, soak in a 5-8% HCl solution by mass for 4-8 h, wash to neutrality, then soak in a 2-4% NaOH solution by mass for 4-8 h, wash to neutrality, load into a column, and exchange the column into a small molecule alcohol column with small molecule alcohol; Disperse the polyethylenepolyamine ionic liquid in a small molecule alcohol solvent and perform ion exchange on a small molecule alcohol column; The volume ratio of the polyethylenepolyamine ionic liquid to the small molecule alcohol is 1:(2-3); The small molecule alcohol is at least one of methanol and ethanol.

7. An ionic liquid graphene oxide composite material prepared by the preparation method according to any one of claims 1-6.

8. Application of the ionic liquid graphene oxide composite material according to claim 7 in adsorbing carbon dioxide.

9. The application according to claim 8, wherein The adsorption temperature is 40-50 °C, and the adsorption pressure is 0.1-0.2 MPa; The regeneration temperature is 80-90 °C.

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