Solid amine co2 adsorbents and methods of making same

Abstract

The application relates to the technical field of carbon dioxide capture, in particular to a solid amine CO2 adsorbent and a preparation method thereof. The solid amine CO2 adsorbent comprises a carrier and an organic amine; the organic amine comprises small-molecule amine and macromolecular amine with a mass ratio of 1:3 to 3:1, the small-molecule amine has a relative molecular mass of less than 500 Da and contains a hydroxyl group, the macromolecular amine has a relative molecular mass of more than 1000 Da, the small-molecule amine and the macromolecular amine are both loaded on the carrier, and at least part of the small-molecule amine is connected between the carrier and the macromolecular amine. The solid amine CO2 adsorbent improves the adsorption performance and the cyclic stability of the solid amine CO2 adsorbent.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of carbon dioxide capture, and particularly relates to a solid amine CO2 adsorbent and a preparation method thereof. BACKGROUND

[0002] The solid amine CO2 adsorbent is loaded with organic amine as an active agent in a porous carrier material as an active site to react with CO2 to achieve adsorption and capture of CO2. The thermal stability and cycle stability of the adsorbent need to be further improved. SUMMARY

[0003] The application discloses a solid amine CO2 adsorbent and a preparation method thereof to improve the adsorption performance and cycle stability of the solid amine CO2 adsorbent.

[0004] To achieve the above-mentioned purpose, in a first aspect, the application discloses a solid amine CO2 adsorbent, which comprises a carrier and an organic amine.

[0005] The organic amine comprises small-molecule amine and large-molecule amine with a mass ratio of 1:3-3:1, the small-molecule amine has a relative molecular mass <500 Da and contains a hydroxyl group, the large-molecule amine has a relative molecular mass >1000 Da, the small-molecule amine and the large-molecule amine are both loaded on the carrier, and at least part of the small-molecule amine is connected between the carrier and the large-molecule amine.

[0006] Further, part of the large-molecule amine is connected with the small-molecule amine through a hydrogen bond, and part of the large-molecule amine is directly loaded on the carrier.

[0007] Further, the small-molecule amine comprises one or more of ethanolamine, diethanolamine, triethanolamine, aminoethyl ethanolamine, methyldiethanolamine and isopropanolamine; and / or,

[0008] The large-molecule amine comprises one or more of polyethyleneimine, polypropyleneimine, polylysine and aminated polystyrene; and / or,

[0009] The carrier is 40 wt% of the solid amine CO2 adsorbent, the small-molecule amine is 15 wt%-45 wt% of the solid amine CO2 adsorbent, and the large-molecule amine is 15 wt%-45 wt% of the solid amine CO2 adsorbent; and / or,

[0010] The carrier comprises any one of microporous material, mesoporous material or macroporous material; and / or,

[0011] The mesoporous material comprises one or more of mesoporous silica, mesoporous carbon material, mesoporous metal oxide, mesoporous metal organic framework and natural mesoporous material.

[0012] Further, the specific surface area of the carrier is 300 m 2 / g~500 m 2 / g; and / or,

[0013] The pore volume of the carrier is 1.5 cm 3 / g~3.5 cm 3 / g; and / or,

[0014] The pore size of the carrier is 25 nm~35 nm.

[0015] In a second aspect, the application discloses a preparation method of the solid amine CO2 adsorbent according to the first aspect, and the preparation method comprises the following steps:

[0016] impregnating the carrier with a first solution containing the small molecule amine to obtain an intermediate;

[0017] impregnating the intermediate with a second solution containing the large molecule amine to obtain a solid amine CO2 adsorbent precursor;

[0018] drying the solid amine CO2 adsorbent precursor to obtain the solid amine CO2 adsorbent.

[0019] Further, the step of preparing the intermediate comprises: adding the small molecule amine into a first solvent, the mass ratio of the small molecule amine in the first solvent is 0.022 g / mL~0.066 g / mL, and stirring at room temperature for 20 min~45 min to obtain a first solution; adding the carrier into the first solution, and stirring and volatilizing at room temperature for 4 h~6 h; wherein, the mass ratio of the carrier and the small molecule amine is 9:5~3:5; and / or,

[0020] The step of preparing the solid amine CO2 adsorbent precursor comprises: dissolving the large molecule amine in a second solvent, the concentration of the large molecule amine in the second solvent is 0.11 g / mL~0.33 g / mL, the mass ratio of the carrier and the large molecule amine is 9:5~3:5, and stirring at room temperature for 20 min~45 min to obtain a second solution; adding the second solution into the volatilized first solution, and stirring and volatilizing for 2 h~4 h; and / or,

[0021] In the step of drying the solid amine CO2 adsorbent precursor to obtain the solid amine CO2 adsorbent, the drying temperature is 40℃~60℃, and the drying time is 5 h~6 h.

[0022] Further, the first solvent is one or more of methanol, ethanol, isopropanol, diethyl ether, tetrahydrofuran, dichloromethane, chloroform, dimethylformamide and dimethylacetamide.

[0023] The second solvent is one or more of methanol, ethanol, isopropanol, diethyl ether, tetrahydrofuran, dichloromethane, chloroform, dimethylformamide, dimethylacetamide.

[0024] Further, the carrier is mesoporous silica, and a preparation method of the mesoporous silica comprises:

[0025] The structure directing agent and the pore adjusting agent are mixed, and under the action of the pH adjusting agent, stirring is carried out at 38-45 DEG C for 2-3 h to obtain a third solution;

[0026] The third solution is added with a third solvent and stirred, and then a silicon source solution is added, and after aging at 40 DEG C for 24 h, aging at 100-120 DEG C for 24 h, and then dehydration at 80-100 DEG C for 4-6 h and calcination at 500-600 DEG C for 4-8 h, the mesoporous silica is obtained.

[0027] Further, the structure directing agent comprises one or more of cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, gemini surfactant, polyethylene oxide-polypropylene oxide-polyethylene oxide; and / or,

[0028] The pore adjusting agent comprises one or more of ammonium fluoride, sodium fluoride, potassium fluoride; and / or,

[0029] The pH adjusting agent comprises one or more of acetic acid, ammonia, hydrochloric acid; and / or,

[0030] The silicon source solution comprises one or more of sodium silicate nonahydrate, potassium silicate, tetraethyl orthosilicate, methyl orthosilicate, propyl orthosilicate, butyl orthosilicate, methyltriethoxysilane; and / or,

[0031] The third solvent comprises one or more of trimethylbenzene, methanol, ethanol, isopropanol, diethyl ether, tetrahydrofuran, dichloromethane, chloroform, dimethylformamide, dimethylacetamide.

[0032] Further, the structure directing agent is polyethylene oxide-polypropylene oxide-polyethylene oxide, the pore adjusting agent is ammonium fluoride, and the silicon source is sodium silicate nonahydrate;

[0033] The mass ratio of the polyethylene oxide-polypropylene oxide-polyethylene oxide to the sodium silicate nonahydrate is 0.30:1-0.375:1, and the mass ratio of the ammonium fluoride to the sodium silicate nonahydrate is 0.006:1-0.0075:1.

[0034] Compared with the prior art, the application has the beneficial effects that:

[0035] The application provides an improved solid amine CO2 adsorbent, which is prepared by arranging mixed small molecule amine and large molecule amine on a carrier, and at least part of the small molecule amine is between the carrier and the large molecule amine. Through the synergistic cooperation of the organic amine in the carrier, the adsorption performance and the cycle stability of the solid amine CO2 adsorbent can be effectively improved.

[0036] In the application, the organic amine loaded on the carrier is a mixed amine. Since the mass ratio of the small molecule amine and the large molecule amine in the mixed amine is 1:3~3:1, and the relative molecular mass of the small molecule amine is <500 Da and the relative molecular mass of the large molecule amine is >1000 Da, on the one hand, it can ensure that the small molecule amine has a certain proportion in the organic amine, so that the small molecule amine can better play the role of reducing the overall viscosity of the organic amine and improving the dispersity of the organic amine, and ensure that when CO2 diffuses into the inside of the pores of the carrier, it has smaller diffusion resistance, thereby improving the adsorption performance of the solid amine CO2 adsorbent, and on the other hand, it can also ensure that the large molecule amine plays its role of good stability in the organic amine.

[0037] In addition, at least part of the small molecule amine is connected between the carrier and the large molecule amine, the small molecule amine has small resistance to the diffusion of CO2, and the small molecule amine inside the large molecule amine can realize rapid adsorption of CO2 again after the concentration gradient of the CO2 diffused and adsorbed through the large molecule amine layer is reduced, thereby further improving the adsorption rate and amine efficiency of the solid amine CO2 adsorbent. More importantly, the small molecule amine in the application has a hydroxyl group and is located between the carrier and the large molecule amine. On the basis of the hydrogen bond action between the hydroxyl group, the amine group of the large molecule amine and the silicon-oxygen bond of the carrier, the large molecule amine plays a protective role on the small molecule amine in the distribution position. Under the joint action of the hydrogen bond and the steric hindrance effect, the possibility of the small molecule amine falling off is further reduced, so that the small molecule amine and the large molecule amine loaded on the carrier both have good adsorption performance and stability, and the cycle stability of the solid amine CO2 adsorbent can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0039] Figure 1 is the SEM image of the mesoporous silica provided by the preparation example of the application;

[0040] Figures 2-4 are the SEM images of the solid amine CO2 adsorbent provided by the example 1, the comparative example 1 and the comparative example 4 of the application, respectively;

[0041] Figures 5-7 are thermogravimetric curves and differential thermogravimetric curves of the solid amine CO2 adsorbents provided by Examples 1-9 and Comparative Examples 1-4 of the present application;

[0042] Figure 8 is a 60-cycle performance test graph of Example 1 of the present application. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be apparently and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those of ordinary skill in the art without any creative work fall within the scope of protection of the present application.

[0044] In addition, the terms "first", "second", and the like are mainly used to distinguish different solutions, and are not used to indicate or imply the relative importance and quantity of the indicated solutions. Unless otherwise specified, the meaning of "a plurality of" is two or more.

[0045] The technical solutions provided by the present application will be further described below with reference to the embodiments and drawings.

[0046] The emission of CO2 leads to the continuous rise of global temperature, which threatens the environment. Therefore, it is crucial to explore and develop direct air CO2 capture technology.

[0047] Among the CO2 capture technologies, solid amine CO2 adsorbents have attracted extensive attention. Solid amine CO2 adsorbents are composite solid adsorbents that load organic amines as active agents inside porous matrix materials as active sites to capture CO2. Among them, the carriers include activated carbon, organic framework materials, high molecular porous polymers, alumina, mesoporous silica, etc. Organic amines can be divided into small molecule amines and macromolecular amines according to their molecular weights. Such adsorbents have the advantages of small corrosion, fast adsorption rate, good adsorption selectivity, and low regeneration energy consumption.

[0048] When the organic amine of the solid amine CO2 adsorbent is a macromolecular amine, the adsorption performance of the solid amine CO2 adsorbent is poor because the macromolecular amine has a high molecular weight and a high viscosity, and the proportion of the macromolecular amine loaded on the carrier is too high, which easily blocks the pores of the carrier and hinders the diffusion of CO2. When the organic amine of the solid amine CO2 adsorbent is a small molecule amine, although the small molecule amine has a low viscosity and a high amine utilization rate, it is easy to decompose and fall off in a high temperature environment, and it is easy to volatilize under long cycle use, which makes the stability of the solid amine CO2 adsorbent poor. Therefore, it is difficult for the current solid amine CO2 adsorbent to simultaneously meet high adsorption performance and high thermal stability.

[0049] The solid amine CO2 adsorbent comprises a carrier and an organic amine.

[0050] The organic amine comprises a small-molecule amine and a large-molecule amine in a mass ratio of 1:3 to 3:1, the small-molecule amine has a relative molecular mass less than 500 Da and contains a hydroxyl group, the large-molecule amine has a relative molecular mass greater than 1000 Da, and the small-molecule amine and the large-molecule amine are both loaded on the carrier, and at least part of the small-molecule amine is connected between the carrier and the large-molecule amine.

[0051] The carrier is used for loading and dispersing the organic amine, can be combined with the organic amine through a covalent bond, a hydrogen bond or a van der Waals force, realizes adsorption and desorption of CO2 by the organic amine in the pore channel of the carrier, and then regenerates and circulates the organic amine after desorption of CO2, for repeated adsorption of CO2.

[0052] The large-molecule amine is an organic amine with a relative molecular mass greater than 1000 Da, which can be a polymer with more than or equal to 10 amine-containing repeating units. Such a large-molecule amine has the advantages of not being easy to volatilize and good stability, but is easy to block the pore channel of the carrier due to a large viscosity, and the amine group density is low, which limits its adsorption performance.

[0053] The small-molecule amine is an organic amine with a relative molecular mass less than 500 Da, which can be a monomer or an oligomer with 2 to 5 amine units. Such a small-molecule amine has the advantages of smaller viscosity, good fluidity and easy penetration into the pores of the carrier. The embodiments of the present application play the above advantages of the small-molecule amine by controlling the mass ratio of the small-molecule amine and the large-molecule amine in a specific range, to solve the problem that the large-molecule amine is stable but easy to block the pore channel of the carrier. However, the small-molecule amine itself has the problems of easy volatilization and poor stability, so the small-molecule amine of the embodiments of the present application also has a hydroxyl group, and at least part of the small-molecule amine is connected between the carrier and the large-molecule amine, to enhance the stability of the small-molecule amine.

[0054] The connection of the small-molecule amine between the carrier and the large-molecule amine means that the small-molecule amine is not exposed to the pore channel of the carrier as the outermost layer, but the outside of the small-molecule amine also has the large-molecule amine, which protects the small-molecule amine and enhances the stability of the small-molecule amine. In addition, in the embodiments of the present application, part of the small-molecule amine can be connected between the carrier and the large-molecule amine, or all of the small-molecule amine can be connected between the carrier and the large-molecule amine, that is, the outside of the small-molecule amine has the large-molecule amine which can play a protective role, so that the small-molecule amine inside the large-molecule amine can have good stability as an active substance for adsorbing CO2.

[0055] In addition, the mass ratio of the small molecule amine and the large molecule amine in the embodiments of the present application is 1:3-3:1, and any ratio within the range is included. For example, the mass ratio of the small molecule amine and the large molecule amine is 1:3, 1:2, 1:1, 2:1 or 3:1.

[0056] The embodiments of the present application provide the improved solid amine CO2 adsorbent described above, which is obtained by arranging mixed small molecule amine and large molecule amine on the carrier, and at least part of the small molecule amine is between the carrier and the large molecule amine. Through the synergistic cooperation of the organic amine in the carrier, the adsorption performance and the cycle stability of the solid amine CO2 adsorbent can be effectively improved.

[0057] In the embodiments of the present application, the organic amine loaded on the carrier is a mixed amine. Since the mass ratio of the small molecule amine and the large molecule amine in the mixed amine is 1:3-3:1, and the relative molecular mass of the small molecule amine is <500 Da and the relative molecular mass of the large molecule amine is >1000 Da, on the one hand, it can ensure that the small molecule amine has a certain proportion in the organic amine, so that the small molecule amine can better play the role of reducing the overall viscosity of the organic amine and improving the dispersibility of the organic amine, and ensure that the CO2 has smaller diffusion resistance when diffusing from the organic amine to the inside of the pore of the carrier, thereby improving the adsorption performance of the solid amine CO2 adsorbent, and on the other hand, it can also ensure that the large molecule amine plays its role of good stability in the organic amine.

[0058] In addition, at least part of the small molecule amine is connected between the carrier and the large molecule amine, and the small molecule amine has small resistance to the diffusion of CO2. The small molecule amine inside the large molecule amine can realize rapid adsorption of CO2 again after the concentration gradient of the CO2 diffused and adsorbed through the large molecule amine layer is reduced, thereby further improving the adsorption performance and amine efficiency of the solid amine CO2 adsorbent. More importantly, the small molecule amine of the present application has a hydroxyl group and is located between the carrier and the large molecule amine. Based on the hydrogen bond action between the hydroxyl group and the amine group of the large molecule amine and the silicon-oxygen bond of the carrier, the large molecule amine plays a protective role on the small molecule amine in the distribution position. Under the combined action of the hydrogen bond and the steric hindrance effect, the possibility of the small molecule amine falling off is further reduced, thereby making the small molecule amine and the large molecule amine loaded on the carrier have good adsorption performance stability, and the cycle stability of the solid amine CO2 adsorbent can be improved.

[0059] Especially when the concentration of CO2 is less than 10000 ppm, the concentration difference of CO2 inside and outside the pore is small, which is not conducive to the diffusion and adsorption reaction of CO2, but the solid amine CO2 adsorbent of the embodiments of the present application can still maintain very good adsorption performance and cycle stability.

[0060] Further, part of the large molecule amine is connected with the small molecule amine through a hydrogen bond, and part of the large molecule amine is directly loaded on the carrier.

[0061] The macromolecular amine can be connected to the small-molecule amine by hydrogen bonds, or can be connected to the small-molecule amine by hydrogen bonds on one part and directly loaded on the carrier on another part. In the embodiments of the present application, the part of the macromolecular amine directly loaded on the carrier has more repeating units, so that the amine content is more than that of the small-molecule amine, the number of groups forming covalent bonds or hydrogen bonds between the carrier and the macromolecular amine is more, and therefore the interaction between the macromolecular amine and the carrier is stronger, and the stability of the organic amine is improved. The macromolecular amine connected to the small-molecule amine by hydrogen bonds has a transition effect of the small-molecule amine between the macromolecular amine and the carrier, so that the compactness between the carrier and the macromolecular amine is reduced, which is beneficial to the diffusion of CO2 in the pores, and further improves the adsorption performance of the solid amine CO2 adsorbent.

[0062] Optionally, the small-molecule amine includes one or more of ethanolamine, diethanolamine, triethanolamine, aminoethyl ethanolamine, methyldiethanolamine, and isopropanolamine. Preferably, the small-molecule amine is diethanolamine.

[0063] In the embodiments of the present application, diethanolamine is preferably used as the small-molecule amine. The diethanolamine molecule contains two hydroxyl groups and one secondary amine group. The hydroxyl group of diethanolamine can change the reaction mechanism of CO2 and the secondary amine, so that each secondary amine captures one molecule of CO2, and the final product is converted from carbamate to carbamic acid, thereby improving the amine efficiency (i.e., the amount of CO2 captured by unit mass of organic amine) and improving the adsorption efficiency of the solid amine CO2 adsorbent. At the same time, the diethanolamine molecule has good dispersibility in the carrier, effectively reducing the agglomeration of the amine.

[0064] Optionally, the macromolecular amine includes one or more of polyethyleneimine, polypropyleneimine, polylysine, and aminated polystyrene. Preferably, the macromolecular amine is polyethyleneimine.

[0065] The polyethyleneimine, polypropyleneimine, polylysine, and aminated polystyrene are all selected to be corresponding polymers with a relative molecular mass greater than 1000 Da.

[0066] In the embodiments of the present application, polyethyleneimine is preferably used as the macromolecular amine. Among macromolecular amines with the same relative molecular mass, polyethyleneimine has a higher amine group density than other macromolecular amines. The high-density amine group has stronger chemical reactivity with CO2, and thus the solid amine CO2 adsorbent has better adsorption performance.

[0067] Further, the carrier includes any one of a mesoporous material, a microporous material, or a macroporous material. Preferably, the carrier is a mesoporous material.

[0068] The mesoporous material has a pore size in the range of 2 nm to 50 nm and a highly ordered pore structure. The microporous material has a pore size less than 2 nm. The macroporous material has a pore size greater than 50 nm.

[0069] In the embodiments of the present application, the mesoporous material is preferably used, and the mesoporous material has moderate pore size compared with microporous material and macroporous material, and matches the molecular size of the organic amine, so that the organic amine molecules can be better distributed on the pore wall or in the pore, and the adsorption performance of the solid amine CO2 adsorbent is improved. Meanwhile, the pore of the material is ordered and has good connectivity, and the structure is not easy to collapse after loading the organic amine, so that the stability of the solid amine CO2 adsorbent is better, and the service life is longer.

[0070] Further, the mesoporous material includes one or more of mesoporous silica, mesoporous carbon material, mesoporous metal oxide, mesoporous metal organic framework, and natural mesoporous material. Preferably, the mesoporous material is mesoporous silica.

[0071] In the embodiments of the present application, mesoporous silica is preferably used as the mesoporous material, and a large number of reactive silicon hydroxyl groups exist on the surface of the mesoporous silica, which can better interact with the organic amine, improve the amine content in the solid amine CO2 adsorbent, and the silicon-oxygen skeleton of the mesoporous silica has strong chemical inertness and will not react with the amine, so that the active component can be uniformly dispersed in the pore and maintain high activity, and the solid amine CO2 adsorbent has better cycle stability.

[0072] Further, the specific surface area of the carrier is 300 m 2 / g~500 m 2 / g.

[0073] Illustratively, the specific surface area of the carrier is 300 m 2 / g, 314 m 2 / g, 325 m 2 / g, 330 m 2 / g, 348 m 2 / g, 355 m 2 / g, 363 m 2 / g, 372 m 2 / g, 388 m 2 / g, 391 m 2 / g, 400 m 2 / g, 413 m 2 / g, 420 m 2 / g, 434 m 2 / g, 440 m 2 / g, 456 m 2 / g, 463 m 2 / g, 472 m 2 / g, 483 m 2 / g, 497 m 2 / g or 500 m 2 / g. Preferably, the specific surface area of the carrier is 400 m2 / g.

[0074] Further, the pore volume of the carrier is 1.5 cm 3 / g, 3.5 cm 3 / g.

[0075] Illustratively, the pore volume of the carrier is 1.5 cm 3 / g, 1.7 cm 3 / g, 1.9 cm 3 / g, 2.1 cm 3 / g, 2.2 cm 3 / g, 2.5 cm 3 / g, 2.7 cm 3 / g, 2.8 cm 3 / g, 3.0 cm 3 / g, 3.1 cm 3 / g, 3.3 cm 3 / g, or 3.5 cm 3 / g. Preferably, the pore volume of the carrier is 2.5 cm 2 / g.

[0076] Further, the pore size of the carrier is 25 nm ~ 35 nm.

[0077] Illustratively, the pore size of the carrier is 25 nm, 27 nm, 30 nm, 31 nm, 33 nm, or 35 nm. Preferably, the pore size of the carrier is 30 nm.

[0078] The specific surface area, pore volume and pore size of the carrier are obtained by nitrogen volume adsorption at 77K by Micromeritics ASAP2020.

[0079] In the embodiments of the present application, when the pore parameters of the carrier are within the above ranges, the loading amount of the organic amine can be ensured, and the stability of the structure of the carrier is not affected, so that the solid amine CO2 adsorbent has good adsorption performance and cycle stability.

[0080] Further, the carrier is 40 wt% of the solid amine CO2 adsorbent, the small molecule amine is 15 wt% ~ 45 wt% of the solid amine CO2 adsorbent, and the large molecule amine is 15 wt% ~ 45 wt% of the solid amine CO2 adsorbent.

[0081] In the embodiments of the present application, 40 wt% of the carrier in the solid amine CO2 adsorbent provides a large number of interaction sites for the organic amine, thereby improving the adsorption performance of the solid amine CO2 adsorbent. The 15 wt%-45 wt% small molecule amine and the 15 wt%-45 wt% macromolecular amine can ensure that the small molecule amine has a certain proportion in the organic amine, so that the small molecule amine can better play a role in reducing the overall viscosity of the organic amine, and ensure that the CO2 has a better diffusion effect when diffusing from the organic amine to the inside of the pore of the carrier, thereby improving the adsorption performance of the solid amine CO2 adsorbent, and on the other hand, the macromolecular amine can also play a role in stability.

[0082] The embodiments of the present application also provide a preparation method of the solid amine CO2 adsorbent. It can be understood that the preparation method is one method for obtaining the embodiments of the present application, but is not limited to the only method. That is, the solid amine CO2 adsorbent of the embodiments of the present application can also be prepared by other methods, which are not limited by the present application, so it should not be understood as the preparation method provided by the embodiments of the present application is limited to the solid amine CO2 adsorbent.

[0083] The preparation method comprises: impregnating the carrier with a first solution containing a small molecule amine to obtain an intermediate; impregnating the intermediate with a second solution containing a macromolecular amine to obtain a solid amine CO2 adsorbent precursor; and drying the solid amine CO2 adsorbent precursor to obtain the solid amine CO2 adsorbent.

[0084] In the embodiments of the present application, the small molecule amine and the macromolecular amine are stepwise impregnated into the carrier. Compared with simultaneously impregnating the small molecule amine and the macromolecular amine into the carrier after mixing, the stepwise impregnation makes the loading of the organic amine on the carrier more controllable, and the solid amine CO2 adsorbent with the small molecule amine located between the carrier and the macromolecular amine is obtained. In addition, the stepwise impregnation also helps the macromolecular amine and the small molecule amine to form hydrogen bond interaction, and finally the solid amine CO2 adsorbent with improved performance is obtained.

[0085] Further, the step of preparing the intermediate comprises: adding the small molecule amine into the first solvent, the concentration of the small molecule amine in the first solvent is 0.022 g / mL-0.066 g / mL, and stirring at room temperature for 20 min-45 min to obtain the first solution; adding the carrier into the first solution, and stirring and volatilizing at room temperature for 4 h-6 h; wherein the mass ratio of the carrier to the small molecule amine is 9:5-3:5.

[0086] Wherein, the room temperature refers to 20±5℃.

[0087] For example, the concentration of the small molecule amine in the first solvent is 0.022 g / mL, 0.026 g / mL, 0.033 g / mL, 0.037 g / mL, 0.048 g / mL, 0.054 g / mL or 0.066 g / mL.

[0088] The stirring time is for example 20 min, 25 min, 30 min, 35 min, 40 min or 45 min.

[0089] The reaction time is for example 4 h, 4.5 h, 5 h, 5.5 h, 6 h. Preferably, the reaction time is 6 h.

[0090] The remaining volume of the first solvent is 15% to 30% after stirring at room temperature for 4 h to 6 h.

[0091] The remaining volume of the first solvent is for example 15%, 18%, 20%, 22%, 25%, 27% or 30%. Preferably, the remaining volume of the first solvent is 20%. In the embodiments of the present application, the amount of the first solvent is reduced after stirring at room temperature, so that the dispersibility of the macromolecular amine is reduced when preparing the solid amine CO2 adsorbent precursor, and the loading effect on the intermediate is better.

[0092] The mass ratio of the carrier to the macromolecular amine is for example 9:5, 8:5, 7:5, 6:5, 1:1, 4:5 or 3:5.

[0093] The reaction temperature is for example 15℃, 18℃, 20℃, 23℃ or 25℃.

[0094] The first solvent is one or more of methanol, ethanol, isopropanol, diethyl ether, tetrahydrofuran, dichloromethane, chloroform, dimethylformamide and dimethylacetamide. Preferably, the first solvent is methanol.

[0095] Further, the step of preparing the solid amine CO2 adsorbent precursor comprises: dissolving the macromolecular amine in a second solvent, the concentration of the macromolecular amine in the second solvent being 0.11 g / mL to 0.33 g / mL, and the mass ratio of the carrier to the macromolecular amine being 8:3 to 2:3; stirring at room temperature for 20 min to 45 min to obtain a second solution; adding the second solution to the first solution after volatilization, and stirring and volatilizing for 2 h to 4 h.

[0096] The concentration of the macromolecular amine in the second solvent is for example 0.11 g / mL, 0.15 g / mL, 0.23 g / mL, 0.29 g / mL or 0.33 g / mL.

[0097] The mass ratio of the carrier to the macromolecular amine is for example 9:5, 8:5, 7:5, 6:5, 1:1, 4:5 or 3:5.

[0098] Exemplarily, the stirring time is 20 min, 25 min, 30 min, 35 min, 40 min or 45 min.

[0099] Exemplarily, the reaction time is 2 h, 2.5 h, 3 h, 3.5 h, 4 h. Preferably, the reaction time is 3 h.

[0100] Further, the second solvent is one or more of methanol, ethanol, isopropanol, diethyl ether, tetrahydrofuran, dichloromethane, chloroform, dimethylformamide, dimethylacetamide. Preferably, the second solvent is methanol.

[0101] Further, in the step of drying the solid amine CO2 adsorbent precursor to obtain the solid amine CO2 adsorbent, the drying temperature is 40℃-60℃, and the drying time is 5 h-6 h.

[0102] Exemplarily, the temperature for preparing the solid amine CO2 adsorbent is 40℃, 45℃, 50℃, 45℃, 50℃, 55℃ or 60℃.

[0103] Exemplarily, the time for preparing the solid amine CO2 adsorbent is 5 h, 5.5 h or 6 h.

[0104] Preferably, the temperature is 60℃, and the time is 5 h.

[0105] Further, the carrier is mesoporous silica, and the preparation method of the mesoporous silica comprises:

[0106] The structure directing agent and the pore adjusting agent are mixed, and under the action of the pH adjusting agent, stirring is performed at 38℃-45℃ for 2-3 h to obtain a third solution;

[0107] The third solution is stirred by adding a third solvent, and then a silicon source solution is added. After aging at 40℃ for 24 h, aging at 100℃-120℃ for 24 h is performed, and then dehydration at 80℃-100℃ for 4 h-6 h and calcination at 500℃-600℃ for 4 h-8 h are performed to obtain the mesoporous silica.

[0108] Exemplarily, the temperature for stirring can be 38℃, 40℃, 42℃ or 45℃. Preferably, the stirring temperature is 38℃.

[0109] Exemplarily, the time for stirring is 2 h, 2.5 h or 3 h. Preferably, the stirring time is 3 h.

[0110] Exemplarily, the temperature for aging again after aging at 40℃ for 24 h is 100℃, 105℃, 110℃, 115℃ or 120℃. Preferably, the aging temperature is 100℃.

[0111] Exemplarily, the temperature of the dehydration is 80℃, 85℃, 90℃, 95℃ or 100℃.

[0112] Exemplarily, the time of the dehydration is 4 h, 4.5 h, 5 h, 5.5 h or 6 h.

[0113] Exemplarily, the temperature of the calcination is 500℃, 510℃, 520℃, 530℃, 540℃, 550℃, 560℃, 570℃, 580℃, 590℃ or 600℃.

[0114] Exemplarily, the time of the calcination is 4 h, 5 h, 6 h, 7 h or 8 h.

[0115] Preferably, the temperature of the calcination is 560℃ and the time of the calcination is 6 h.

[0116] Further, the structure-directing agent comprises one or more of cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, gemini surfactant, poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide). Preferably, the structure-directing agent is poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide).

[0117] Further, the orifice-regulating agent comprises one or more of ammonium fluoride, sodium fluoride, potassium fluoride. Preferably, the orifice-regulating agent is ammonium fluoride.

[0118] Further, the pH-regulating agent comprises one or more of acetic acid, ammonia, hydrochloric acid. Preferably, the pH-regulating agent is acetic acid.

[0119] Further, the silicon source solution comprises one or more of sodium silicate nonahydrate, potassium silicate, tetraethyl orthosilicate, tetramethyl orthosilicate, tetrapropyl orthosilicate, tetrabutyl orthosilicate, methyltriethoxysilane. Preferably, the silicon source solution is sodium silicate nonahydrate.

[0120] Further, the third solvent comprises one or more of trimethylbenzene, methanol, ethanol, isopropanol, diethyl ether, tetrahydrofuran, dichloromethane, chloroform, dimethylformamide, dimethylacetamide. Preferably, the third solvent is trimethylbenzene.

[0121] Further, the mass ratio of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) to sodium silicate nonahydrate is 0.30:1~0.375:1, and the mass ratio of ammonium fluoride to sodium silicate nonahydrate is 0.006:1~0.0075:1.

[0122] Preferably, the mass ratio of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) to sodium silicate nonahydrate is 0.375:1, and the mass ratio of ammonium fluoride to sodium silicate nonahydrate is 0.0075:1.

[0123] It is observed by scanning electron microscope that the obtained mesoporous silica has pores in the form of nearly hexagonal honeycomb chambers with a diameter of about 30 nm, and the walls of the honeycomb pores are interconnected to form a whole morphology similar to a honeycomb with regular and ordered pore structure.

[0124] In the embodiments of the present application, when the mass ratio of polyethylene oxide-polypropylene oxide-polyethylene oxide to sodium silicate nonahydrate is 0.30:1-0.47:1, the polyethylene oxide-polypropylene oxide-polyethylene oxide can ensure the role of pore structure guidance, and the surface of the obtained mesoporous silica has a regular empty morphology, which is beneficial to the diffusion of CO2. When the mass ratio of ammonium fluoride to sodium silicate nonahydrate is 0.00345:1-0.00820:1, the wall thickness of the mesoporous silica gap and the connecting window between adjacent pores can provide more loading sites for organic amines under the condition that the mesoporous silica is stable, thereby improving the adsorption performance of the solid amine CO2 adsorbent.

[0125] The technical solutions of the present application will be further explained in combination with more specific embodiments and experimental test results.

[0126] Preparation Example

[0127] The present preparation example provides a kind of mesoporous silica.

[0128] 4.47 g of acetic acid, 3 g of polyethylene oxide-polypropylene oxide-polyethylene oxide, 0.06 g of ammonium fluoride and 50 g of water are added to a beaker, and stirred at 40 DEG C for 120 min until the solution is clear and no flocculation remains. 4 g of mesitylene is added, and then 40 mL of a sodium silicate nonahydrate solution with a concentration of 225 g / L is added dropwise to the solution.

[0129] The above solution is placed in a reaction kettle and aged at 45 DEG C for 24 h, and then aged at 100 DEG C for 24 h. The obtained sample is washed with pure water and filtered for more than 5 times, and then dried at 100 DEG C for 6 h, and then calcined at 560 DEG C for 6 h to obtain mesoporous silica.

[0130] Example 1

[0131] The present embodiment provides a kind of solid amine CO2 silicon-based adsorbent.

[0132] 1.1 g of diethanolamine is added to 25 mL of methanol solution, stirred and dissolved to make diethanolamine uniformly dispersed, 1.0 g of mesoporous silica of the preparation example is added, stirred at room temperature for 6 h until methanol is volatilized to 10 mL, 1.1 g of polyethyleneimine is dissolved in 5 mL of methanol and then added to the solution, and the stirring is continued until the methanol is completely volatilized. Then it is placed in a vacuum drying oven and dried at 60 DEG C for 6 h to obtain a solid amine CO2 silicon-based adsorbent.

[0133] Example 2

[0134] The difference between this example and Example 1 is that the mass of diethanolamine is 0.55 g and the mass of polyethyleneimine is 1.65 g.

[0135] Example 3

[0136] The difference between this example and Example 1 is that the mass of diethanolamine is 1.65 g and the mass of polyethyleneimine is 0.55 g.

[0137] Example 4

[0138] The difference between this example and Example 1 is that diethanolamine is replaced by aminoethylethanolamine.

[0139] Example 5

[0140] The difference between this example and Example 4 is that the mass of aminoethylethanolamine is 0.55 g and the mass of polyethyleneimine is 1.65 g.

[0141] Example 6

[0142] The difference between this example and Example 4 is that the mass of aminoethylethanolamine is 1.65 g and the mass of polyethyleneimine is 0.55 g.

[0143] Example 7

[0144] The difference between this example and Example 1 is that diethanolamine is replaced by diethylenetriamine.

[0145] Example 8

[0146] The difference between this example and Example 7 is that the mass of diethylenetriamine is 0.55 g and the mass of polyethyleneimine is 1.65 g.

[0147] Example 9

[0148] The difference between this example and Example 7 is that the mass of diethylenetriamine is 1.65 g and the mass of polyethyleneimine is 0.55 g.

[0149] Comparative Example 1

[0150] 2.2 g of diethanolamine was added to a 25 mL methanol solution, stirred to dissolve, so that the diethanolamine was uniformly dispersed, 1.0 g of mesoporous silica prepared in the preparation example was added, and stirred at room temperature for 8 h until the methanol was completely volatilized. Then it was placed in a vacuum drying oven at 60°C and dried for 5 h to obtain a solid amine CO2 adsorbent.

[0151] Comparative Example 2

[0152] The only difference between this comparative example and Comparative Example 1 is that diethanolamine is replaced with aminoethylethanolamine.

[0153] Comparative Example 3

[0154] The only difference between this comparative example and comparative example 1 is that diethanolamine is replaced with diethylenetriamine.

[0155] Comparative Example 4

[0156] The only difference between this comparative example and Comparative Example 1 is that diethanolamine is replaced with polyethyleneimine.

[0157] Performance testing:

[0158] 1. Characterization of the pore structure of mesoporous silica

[0159] The preparation examples and Example 1 were tested using a scanning electron microscope, which was a Zeiss Gemini 300.

[0160] The scanning electron microscope test results of the preparation example are as follows: Figure 1 As shown. The scanning electron microscope test results of Example 1, Comparative Example 1, and Comparative Example 4 are as follows. Figures 2-4 As shown.

[0161] like Figure 1 As shown, the pores of the mesoporous silica obtained in the preparation examples all exhibit a near-hexagonal honeycomb-like structure with a diameter of approximately 30 nm. The interconnected walls of adjacent honeycomb pores form an overall morphology resembling a honeycomb with regular and ordered pores. Figures 2-4 As shown, organic amines are supported on mesoporous silica.

[0162] 2. Pore parameter testing of mesoporous silica

[0163] The prepared samples were tested for nitrogen volume adsorption at 77 K using a specific surface area and porosity analyzer, model Micromeritics ASAP2020.

[0164] The specific surface area of ​​the prepared example was 331.8 m². 2 / g, pore volume 2.49 cm³ 2 / g, with a pore size of 33.9 nm.

[0165] 3. Viscosity test of mixed organic amines

[0166] The macromolecular amines and small molecular amines of Examples 1-9 were mixed in a mass ratio, stirred and left to stand for 12 h, and then the viscosity was tested at 25°C. The viscosity of the amines of Comparative Examples 1-4 was also tested at 25°C. Each test was performed in triplicate, and the results were averaged. The testing instrument was an NDJ series digital rotary viscometer. The test results are shown in Table 1.

[0167] 4. Thermogravimetric test of solid amine CO2silica-based adsorbents

[0168] The solid amine CO2silica-based adsorbents obtained from Examples 1-9 and Comparative Examples 1-4 were subjected to thermal decomposition tests under temperature rising conditions using a thermogravimetric analyzer, and the thermogravimetric curves and differential thermogravimetric curves of the polymers are shown in Figures 5-7

[0169] The model of the thermogravimetric analyzer was SETARAM SETSYS EVO 18.

[0170] As shown in Figure 5 , in the thermogravimetric curve corresponding to Comparative Example 1, diethanolamine decomposed within 130°C-265°C. According to the differential thermogravimetric curve, the maximum decomposition rate point appeared at 235°C; in the thermogravimetric curve corresponding to Comparative Example 4, the adsorption of water and the volatilization of solvents mainly occurred before 130°C, and polyethyleneimine began to decompose after 265°C, and according to the differential thermogravimetric curve, the maximum decomposition rate point appeared at 349°C; in the thermogravimetric curves corresponding to Examples 1-3, the thermal decomposition temperature and mass of the solid amine CO2silica-based adsorbents changed accordingly with the change in the mass ratio of polyethyleneimine and diethanolamine.

[0171] As shown in Figure 6 , in the thermogravimetric curve corresponding to Comparative Example 2, aminoethyl ethanolamine decomposed within 120°C-250°C, and according to the differential thermogravimetric curve, the maximum decomposition rate point appeared at 215°C, which was lower than that of diethanolamine; the thermogravimetric curve corresponding to Comparative Example 4 was as described above, and the maximum decomposition rate point of polyethyleneimine appeared at 349°C; in the thermogravimetric curves corresponding to Examples 4-6, the thermal decomposition temperature and mass of the solid amine CO2silica-based adsorbents changed accordingly with the change in the mass ratio of polyethyleneimine and aminoethyl ethanolamine.

[0172] As shown in Figure 7 ​As shown, in the thermal gravimetric curve corresponding to Comparative Example 3, diethylenetriamine decomposes at 110°C~230°C, and according to the differential thermal gravimetric curve, the maximum decomposition rate point appears at 190°C; the thermal gravimetric curve corresponding to Comparative Example 4 is as described above, and the maximum decomposition rate point of polyethyleneimine appears at 349°C; in the thermal gravimetric curves corresponding to Example 7~Example 9, with the change of the mass ratio of polyethyleneimine and diethylenetriamine, the thermal decomposition temperature and mass of the solid amine CO2silicon-based adsorbent change accordingly.

[0173] As shown above, diethanolamine contains the largest number of hydroxyl groups, and its thermal decomposition temperature is higher, indicating that diethanolamine has better thermal stability as a mixed solid amine adsorbent of small molecule amines.

[0174] 5. Adsorption performance test of solid amine CO2silicon-based adsorbent

[0175] 10 mg of the sample was placed in a crucible in a thermal analyzer, 10000 ppm CO2was introduced into the instrument at 50 mL / min, the sample was first heated to 100°C at 10°C / min for degassing for 30 min, and then cooled to 25°C for adsorption experiment, and the adsorption process was 60 min. In the regeneration experiment, the gas flow was switched to argon, and the regeneration was carried out at 100°C for 30 min. The model of the thermal analyzer was SETARAM SETSYS EVO 18.

[0176] The samples were Example 1~Example 9 and Comparative Example 1~Comparative Example 4. The adsorption performance of the samples is shown in Table 1.

[0177] 6. Cycle stability performance test of solid amine CO2silicon-based adsorbent

[0178] In the cycle adsorption process, the adsorption time of the sample in a single adsorption process was 45 min, and the regeneration time was 15 min.

[0179] The cycle test results of the samples of Example 1, Example 4, Example 7 and Comparative Example 1~Comparative Example 4 are shown in Table 2.

[0180] The 60-cycle stability performance test results of Example 1 are shown in Table 3. Figure 8

[0181] Table 1. Viscosity and adsorption performance test results of Example 1~Example 9 and Comparative Example 1~Comparative Example 4

[0182]

[0183] Note: (1) " / " indicates that there is no test data.

[0184] ​(2) Theoretical adsorption capacity represents the adsorption capacity of pure macromolecular amine, and the single adsorption capacity of pure small molecule amine and the theoretical value calculated by loading ratio. For example, the theoretical adsorption capacity of Example 1 = (single adsorption capacity of Comparative Example 1 + single adsorption capacity of Comparative Example 4) / 2; the theoretical adsorption capacity of Example 2 = (single adsorption capacity of Comparative Example 1 x 1 + single adsorption capacity of Comparative Example 4 x 3) / 4.

[0185] (3) The promotion rate = (single adsorption capacity - theoretical adsorption capacity) / theoretical adsorption capacity * 100%.

[0186] Table 2. Test results of the cycle stability performance of Example 1, Example 4, Example 7 and Comparative Examples 1-4

[0187]

[0188] From the test results of Table 1 and Table 2, and Figure 8 The following conclusions can be drawn:

[0189] Examples 1-6 and Examples 8-9 have higher actual single adsorption capacity than the theoretical adsorption capacity, and the adsorption performance is improved compared with the solid amine CO2 silica-based adsorbent prepared by using small molecule amine or macromolecular amine raw material alone. According to the viscosity results in Table 1, the viscosity of the organic amine of Examples 1-9 is less than that of Comparative Example 4, indicating that when small molecule amine is added to macromolecular amine, the viscosity of the organic amine decreases, further improving the dispersibility of the organic amine, which is beneficial to the diffusion of carbon dioxide in the pores, and promotes the improvement of the adsorption performance. The small molecule amine in the organic amine of Example 7 is diethylenetriamine, which is different from diethanolamine and aminoethyl ethanol in that it does not have a hydroxyl group, so its adsorption capacity is not improved, and the single adsorption capacity is slightly lower than the theoretical adsorption capacity. However, according to Table 2, Example 7 has better cycle adsorption capacity than Comparative Example 3.

[0190] The solid amine CO2 adsorbent and the preparation method thereof disclosed in the embodiments of the present application are described in detail above, and specific examples are applied to explain the principles and implementation modes of the present application. The above description of the embodiments is only used to help understand the technical solutions and core ideas of the present application. Meanwhile, for those skilled in the art, according to the ideas of the present application, the specific implementation modes and application ranges will be changed, and the content of the specification should not be understood as a limitation of the present application.

Claims

1. A solid amine CO2 adsorbent characterized in that, The solid amine CO2 adsorbent comprises a carrier and an organic amine; The organic amine comprises a small-molecule amine and a large-molecule amine in a mass ratio of 1:3 to 3:1, the small-molecule amine has a relative molecular mass less than 500 Da and contains a hydroxyl group, the large-molecule amine has a relative molecular mass greater than 1000 Da, the small-molecule amine and the large-molecule amine are both loaded on the carrier, and at least part of the small-molecule amine is connected between the carrier and the large-molecule amine, and at least part of the large-molecule amine is connected to the small-molecule amine by a hydrogen bond; The small-molecule amine comprises one or more of ethanolamine, diethanolamine, triethanolamine, aminoethyl ethanolamine, methyldiethanolamine, and isopropanolamine. The large-molecule amine comprises one or more of polyethyleneimine, polypropyleneimine, polylysine, and aminated polystyrene. The carrier comprises any one of microporous material, mesoporous material, or macroporous material.

2. The solid amine CO2 adsorbent of claim 1, wherein, Part of the large-molecule amine is connected to the small-molecule amine by a hydrogen bond, and part of the large-molecule amine is directly loaded on the carrier.

3. The solid amine CO2 adsorbent of claim 1, wherein, The carrier accounts for 40 wt% of the solid amine CO2 adsorbent, the small-molecule amine accounts for 15 wt% to 45 wt% of the solid amine CO2 adsorbent, and the large-molecule amine accounts for 15 wt% to 45 wt% of the solid amine CO2 adsorbent; and / or The mesoporous material comprises one or more of mesoporous silica, mesoporous carbon material, mesoporous metal oxide, mesoporous metal organic framework, and natural mesoporous material.

4. The solid amine CO2 adsorbent of claim 1, wherein, The specific surface area of the support is 300 m 2 / g~500 m 2 / g; and / or, The pore volume of the carrier is 1.5 cm 3 / g~3.5 cm 3 / g; and / or, The carrier has a pore size of 25 nm to 35 nm.

5. A method of preparing a solid amine CO2 adsorbent as claimed in any one of claims 1 to 4, characterised in that, The preparation method comprises: immersing the carrier in a first solution containing the small-molecule amine to obtain an intermediate; immersing the intermediate in a second solution containing the large-molecule amine to obtain a solid amine CO2 adsorbent precursor; drying the solid amine CO2 adsorbent precursor to obtain the solid amine CO2 adsorbent.

6. The production method according to claim 5, wherein The step of preparing the intermediate comprises: adding the small-molecule amine to a first solvent, the concentration of the small-molecule amine in the first solvent being 0.022 g / mL to 0.066 g / mL, stirring at room temperature for 20 min to 45 min to obtain a first solution; adding the carrier to the first solution, and stirring and volatilizing at room temperature for 4 h to 6 h; wherein the mass ratio of the carrier to the small-molecule amine is 9:5 to 3:5; and / or The step of preparing the solid amine CO2 adsorbent precursor comprises: dissolving the large-molecule amine in a second solvent, the concentration of the large-molecule amine in the second solvent being 0.11 g / mL to 0.33 g / mL, the mass ratio of the carrier to the large-molecule amine being 9:5 to 3:5, and stirring at room temperature for 20 min to 45 min to obtain a second solution; adding the second solution to the volatilized first solution, and stirring and volatilizing for 2 h to 4 h; and / or In the step of drying the solid amine CO2 adsorbent precursor to obtain the solid amine CO2 adsorbent, the drying temperature is 40°C to 60°C, and the drying time is 5 h to 6 h.

7. The production method according to claim 6, characterized by, The first solvent is one or more of methanol, ethanol, isopropanol, diethyl ether, tetrahydrofuran, dichloromethane, chloroform, dimethylformamide, dimethylacetamide; The second solvent is one or more of methanol, ethanol, isopropanol, diethyl ether, tetrahydrofuran, dichloromethane, chloroform, dimethylformamide, dimethylacetamide.

8. The preparation method according to claim 5, characterized in that, The carrier is mesoporous silica, and a preparation method of the mesoporous silica comprises: The structure directing agent and the pore adjusting agent are mixed, and under the action of the pH adjusting agent, stirring is carried out at 38-45 DEG C for 2-3 h to obtain a third solution; The third solvent is added to the third solution and stirred, and then a silicon source solution is added, and after aging at 40 DEG C for 24 h and then aging at 100-120 DEG C for 24 h, the mesoporous silica is obtained by dehydrating at 80-100 DEG C for 4-6 h and calcining at 500-600 DEG C for 4-8 h.

9. The production method according to claim 8, characterized by, The structure directing agent comprises one or more of cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, gemini surfactant, polyethylene oxide-polypropylene oxide-polyethylene oxide; and / or, The pore adjusting agent comprises one or more of ammonium fluoride, sodium fluoride and potassium fluoride; and / or, The pH adjusting agent comprises one or more of acetic acid, ammonia and hydrochloric acid; and / or, The silicon source solution comprises one or more of sodium silicate nonahydrate, potassium silicate, tetraethyl orthosilicate, methyltrimethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane and methyltriethoxysilane; and / or, The third solvent comprises one or more of trimethylbenzene, methanol, ethanol, isopropanol, diethyl ether, tetrahydrofuran, dichloromethane, chloroform, dimethylformamide and dimethylacetamide.

10. The method of claim 9, wherein, The structure directing agent is polyethylene oxide-polypropylene oxide-polyethylene oxide, the pore adjusting agent is ammonium fluoride, and the silicon source is sodium silicate nonahydrate; The mass ratio of the polyethylene oxide-polypropylene oxide-polyethylene oxide to the sodium silicate nonahydrate is 0.30:1-0.375:1, and the mass ratio of the ammonium fluoride to the sodium silicate nonahydrate is 0.006:1-0.0075:1.

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