Pillared metal-organic framework material and preparation method therefor, and adsorbent

Abstract

The present invention relates to a pillared metal-organic framework material and a preparation method therefor, and an adsorbent. The pillared metal-organic framework material has a molecular formula of C6H6N8O5Zn2 and is a compound Zn-OX-ATZ formed by reacting ZnOX, i.e., zinc oxalate dihydrate Zn(C2O4)·2H2O, serving as a metal salt source, with ATZ-3-amino-1,2,4-triazole serving as an organic ligand, in a hydrothermal environment, wherein the Zn-OX-ATZ is a crystalline material. The present invention realizes the kilogram-scale synthesis of Zn-OX-ATZ for the first time, and this compound is used to selectively capture carbon dioxide from flue gas under working conditions so as to achieve the capability of one-step flue gas purification, is expected to replace a current high-energy-consumption carbon dioxide absorption process based on an organic amine solution, and has great application potential in industrial applications involving flue gas purification.

Description

A pillar-supported metal-organic framework material, its preparation method, and adsorbent Technical Field

[0001] This invention relates to the field of metal-organic framework technology, and in particular to a pillar-supported metal-organic framework material, its preparation method, and its adsorbent. Background Technology

[0002] Current carbon dioxide capture technologies for flue gas primarily rely on organic amine solvent systems. The principle behind this process is that carbon dioxide reacts chemically with an amine solution to form unstable salts, which, upon heating, release the carbon dioxide again. While this process effectively removes carbon dioxide, organic amines have significant limitations in carbon dioxide absorption, mainly due to high regeneration energy consumption and the potential for amine decomposition during regeneration, leading to the release of toxic substances. Therefore, developing a more energy-efficient, effective, and safer method for capturing carbon dioxide from flue gas is essential.

[0003] While some MOFs have been reported for selectively adsorbing carbon dioxide from flue gas, most MOF materials experience a significant reduction in adsorption capacity and selectivity for carbon dioxide under humid conditions due to competition between water and carbon dioxide. Furthermore, moisture often leads to the degradation of some MOFs with high selective adsorption performance for carbon dioxide. This situation prevents most MOFs from achieving efficient carbon dioxide capture from flue gas under practical operating conditions (e.g., 318 K, 30-70% RH). Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a pillar-supported metal-organic framework material for use as an adsorbent to achieve efficient capture of carbon dioxide in flue gas.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A pillar-supported metal-organic framework material with the molecular formula C6H6N8O5Zn2 is generated by reacting ZnOX-zinc oxalate dihydrate Zn(C2O4)·2H2O as a metal salt source with ATZ-3-amino-1,2,4-triazole as an organic ligand under a hydrothermal environment to form the compound Zn-OX-ATZ, wherein Zn-OX-ATZ is a crystalline material.

[0006] Furthermore, in the molecular structure of the compound Zn-OX-ATZ, the structural unit includes Zn. 2+ ATZ and C2O4 2- Among them, Zn 2+ It combines with three N atoms from different ATZs to form planar layers, and the different planar layers are connected by C2O4. 2- Connecting is performed, where C2O4 2-The four oxygen atoms are respectively bonded to two different layers of Zn 2+ Ions linked together.

[0007] Furthermore, the crystal structure of the compound Zn-OX-ATZ has one-dimensional channels; the BET specific surface area of ​​Zn-OX-ATZ is 303.3 cm². 2 / g; the pore volume of the Zn-OX-ATZ is 0.15cm³. 3 / g; the pore size distribution of the Zn-OX-ATZ is concentrated in

[0008] Furthermore, the pores contain -NH2 groups, which can generate stronger interactions with carbon dioxide, thereby enabling the capture of carbon dioxide from the flue gas.

[0009] Furthermore, the crystallographic parameters of the compound Zn-OX-ATZ are as follows:

[0010] This invention provides a preparation method for preparing the pillar-supported metal-organic framework material described in the above embodiments, comprising the following steps: Step S1, preparing the reaction system: dispersing zinc oxalate dihydrate Zn(C2O4)·2H2O and 3-amino-1,2,4-triazole in a solvent to form a homogeneous mixture; Step S2, carrying out the synthesis reaction under hydrothermal conditions to obtain a product containing Zn-OX-ATZ; Step S3, separating and purifying the product containing Zn-OX-ATZ to obtain a Zn-OX-ATZ crystalline material.

[0011] Preferably, in step S1: the solvent is water; the molar ratio of zinc oxalate dihydrate to 3-amino-1,2,4-triazole is 1:3-6; the ratio of zinc oxalate dihydrate to solvent is 3-8 mL of solvent for every 1 mmol of zinc oxalate dihydrate; in step S2: the reaction temperature under hydrothermal conditions is 150-190℃.

[0012] The preparation method further includes step S4, activating the Zn-OX-ATZ crystalline material obtained in step S3 to obtain an adsorbent material; preferably, the activation temperature is 120-180℃.

[0013] The present invention provides an adsorbent, which uses the pillar-supported metal-organic framework material described in the above embodiments as an adsorbent for capturing carbon dioxide.

[0014] In some embodiments, the adsorbent is used to selectively capture carbon dioxide from flue gas through a physical adsorption method to purify the flue gas; the adsorption temperature of the physical adsorption method is 0-60°C, the adsorption pressure is 0-3 bar, the desorption temperature is 50-180°C, and the desorption pressure is 0.01-1.0 bar; the physical adsorption method uses an adsorption column.

[0015] The beneficial effects of this invention are: The metal-organic framework (MOF) Zn-OX-ATZ of this invention, when used as an adsorbent, has low cost and high stability. It can efficiently capture carbon dioxide from flue gas by adsorption separation (even under operating conditions of 318±50K, 30-70%RH) to reduce carbon dioxide emissions and help achieve the "dual carbon" target. Attached Figure Description

[0016] Figure 1 shows the coordination diagram of different building units of the pillar-supported metal-organic framework material Zn-OX-ATZ according to an embodiment of the present invention, wherein (a) shows the coordination environment of Zn-OX-ATZ and (b) shows a schematic diagram of the structure of Zn-OX-ATZ.

[0017] Figure 2 shows the X-ray diffraction patterns of the Zn-OX-ATZ materials obtained in Examples 1 to 3 of the present invention.

[0018] Figure 3 shows the CO2 adsorption-desorption isotherm and pore size distribution of the Zn-OX-ATZ material obtained in Example 1 of the present invention at 195K.

[0019] Figure 4 shows the adsorption isotherms of carbon dioxide and nitrogen gas on the Zn-OX-ATZ material obtained in Example 1 of the present invention at 298 and 318 K.

[0020] Figure 5 shows the selectivity of the Zn-OX-ATZ material obtained in Example 1 of the present invention for carbon dioxide / nitrogen at 298K and 318K.

[0021] Figure 6 shows the dynamic breakthrough curves and cyclic dynamic breakthrough curves of the adsorption methods of Application Example 1 and Application Example 2 of the present invention. Among them, (a) shows the dynamic breakthrough curves of the adsorption methods of Application Example 1 and Application Example 2 under the conditions of 318K and dry or 70%RH, and (b) shows the cyclic dynamic breakthrough curves of the adsorption method of Application Example 2 under the conditions of 318K and 70%RH.

[0022] Figure 7 shows the dynamic breakthrough curves of the adsorption method of the present invention in application example three, under dry conditions at 318K or under 70% RH conditions, for simulated industrial flue gas. Detailed Implementation

[0023] Exemplary embodiments of this application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of this application are shown in the drawings, it should be understood that this application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of this application and to fully convey the scope of this application to those skilled in the art.

[0024] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0025] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; the reagents and materials described are commercially available unless otherwise specified.

[0026] The endpoints and any values ​​disclosed in this invention are not limited to the precise range or value, and such ranges or values ​​should be understood to include values ​​close to such 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.

[0027] This invention relates to a metal-organic framework material, Zn-OX-ATZ, with the molecular formula C6H6N8O5Zn2. It is a layered pillar-supported microporous material used as an adsorbent. It features low cost and high stability and can efficiently capture carbon dioxide from flue gas (e.g., CO2 / N2 = 15 / 85 v / v) using adsorption separation (even under operating conditions of 318±50 K, 30-70% RH), thereby reducing carbon dioxide emissions and contributing to the achievement of the "dual carbon" target.

[0028] Specifically, this invention synthesizes the pillar-supported ultraporous material—Zn-OX-ATZ—using low-cost zinc oxalate dihydrate (Zn(C2O4)·2H2O, abbreviated as ZnOX) and 3-amino-1,2,4-triazole (abbreviated as ATZ) as raw materials. The reaction principle is as follows: zinc oxalate dihydrate dissolves into Zn under high-temperature hydrothermal conditions.2+ and C2O4 2- ATZ removes the H atom from the triazole to form an anion; driven by molecular thermodynamics and electrostatic interactions between anions and cations, it self-assembles into a three-dimensional pillared structure; among which Zn 2+ It combines with three N atoms from different ATZs to form planar layers, and then the different planar layers pass through C2O4. 2- Connecting is performed, where C2O4 2- The four oxygen atoms are respectively bonded to two different layers of Zn 2+ Ions are linked together, and the three components work together to form a layered pillar-supported ultraporous metal-organic framework material MOF (Zn-OX-ATZ) with one-dimensional channels.

[0029] Referring to Figure 1, the Zn-OX-ATZ material synthesized in this embodiment of the invention (a larger crystal can be selected) was analyzed by X-ray single-crystal diffraction (SC-XRD) to determine the crystal structure of Zn-OX-ATZ. The specific molecular coordination mode is shown in Figure 1(a). 2+ (Yellow) is coordinated with three N atoms from different ATZs and with C2O4. 2- The O atom is coordinated; C2O4 2- O (red) and different Zn 2+ Coordination, while ATZ connects three N atoms (blue) with three different Zn atoms. 2+ Coordination. The coordination of the above structural units together constructs the three-dimensional structure of Zn-OX-ATZ, as shown in Figure 1(b). It can be seen that the crystal has obvious one-dimensional channels.

[0030] Using Zn-OX-ATZ as the adsorbent, adsorption tests were conducted with carbon dioxide at 195 K. The pore structure of Zn-OX-ATZ was determined, and its BET specific surface area was approximately 303.3 cm². 2 / g, pore volume approximately 0.15cm³ 3 / g, pore size distribution is concentrated in The Zn-OX-ATZ material not only provides suitable pore size for carbon dioxide molecule adsorption, but also has abundant -NH2 groups inside the pores, which can generate stronger interactions with carbon dioxide, thereby achieving complete capture of carbon dioxide from flue gas and thus achieving the ability to purify flue gas in one step.

[0031] Table 1 shows the crystallographic parameters of the Zn-OX-ATZ compounds synthesized in the embodiments of the present invention: Table 1 Crystallographic parameters of Zn-OX-ATZ

[0032] The layered pillar-supported metal-organic framework material Zn-OX-ATZ of the present invention is a metal-organic framework material generated by reacting zinc oxalate dihydrate (Zn(C2O4)·2H2O) as a metal salt source and 3-amino-1,2,4-triazole (ATZ) as an organic ligand under a hydrothermal environment. The preparation method of Zn-OX-ATZ material includes the following steps: Step S1, preparing the reactant system, dispersing a certain proportion of zinc oxalate dihydrate (Zn(C2O4)·2H2O) and 3-amino-1,2,4-triazole in a certain amount of solvent to form a homogeneous mixture, and then transferring the mixture to a stainless steel reactor lined with Teflon; Step S2, carrying out the synthesis reaction under a hydrothermal environment to obtain a Zn-OX-ATZ product sample, specifically by placing the reactor in an oven and reacting at a predetermined reaction temperature for a certain time. Step S3, separation and purification, for example, obtaining a white powder by filtering the product sample, washing with (but not limited to) ethanol and water multiple times to remove unreacted salts and ligands in the sample, to obtain Zn-OX-ATZ crystals; Step S4, activation of the crystals, activating the crystals under vacuum at a predetermined activation temperature for a predetermined time to remove water from the crystal channels, thereby obtaining activated Zn-OX-ATZ crystal samples.

[0033] Preferably, in step S1, the solvent is water.

[0034] Preferably, in step S1, the molar ratio of zinc oxalate dihydrate and 3-amino-1,2,4-triazole is 1:3 to 6, and more preferably, the ratio is 1:4.5.

[0035] Preferably, in step S1, the ratio of zinc oxalate dihydrate to water is 3 to 8 mL of water for every 1 mmol of zinc oxalate dihydrate; more preferably, the amount of water added is 5 mL for every 1 mmol of zinc oxalate dihydrate.

[0036] In step S1, ultrasonic dispersion or stirring can be used to uniformly disperse the raw material reactants in the solvent.

[0037] Preferably, in step S2, the reaction temperature is 150-190°C, more preferably, the reaction temperature is 180°C.

[0038] Preferably, in step S4, the activation temperature of the crystalline material is 120-180°C, and the activation time can be 12 hours; more preferably, the activation temperature is 150°C.

[0039] The Zn-OX-ATZ metal-organic framework (MOFs) of the present invention are used as adsorbents and selectively adsorb carbon dioxide to purify flue gas.

[0040] Experiments have shown that when a binary gas mixture of carbon dioxide and nitrogen is passed through the synthesized Zn-OX-ATZ adsorbent, the adsorbent selectively adsorbs the carbon dioxide in the gas mixture, thus purifying the flue gas.

[0041] The adsorption process can employ one or more combinations of adsorption methods such as pressure swing adsorption with a fixed bed, temperature swing adsorption, or low-pressure adsorption-desorption.

[0042] The specific process of the adsorption procedure is as follows: Under the set adsorption temperature and pressure, the mixed gas is introduced into a fixed bed packed with Zn-OX-ATZ adsorbent at a set flow rate. Nitrogen preferentially penetrates the bed, while carbon dioxide is enriched in the adsorption bed. After carbon dioxide penetration, the bed is regenerated through desorption for the next cycle.

[0043] In some embodiments, the adsorption temperature is 0–60°C, the adsorption pressure is 0–3 bar, the desorption temperature is 50–180°C, and the desorption pressure is 0.01–1.0 bar.

[0044] Example 1: This example describes the synthesis of a metal-organic framework (MOF) material, Zn-OX-ATZ. The specific preparation method is as follows: Zn(C2O4)·2H2O (0.1 mmol) and 3-amino-1,2,4-triazole (0.45 mmol) were ultrasonically dispersed in water (5 mL). The mixture was then transferred to a Teflon-lined reactor and reacted in an oven at 180°C for 2 days. The product was obtained by filtration and then washed five times with ethanol and water to remove unreacted salts and ligands, yielding Zn-OX-ATZ crystals. These crystals were then vacuum-dried at 150°C for 5 hours to obtain activated Zn-OX-ATZ, which can be used as an adsorbent.

[0045] The Zn-OX-ATZ material obtained in Example 1 underwent CO2 adsorption-desorption testing at 195 K. The adsorption-desorption isotherms and pore size distribution are shown in Figure 3. As can be seen from the figure, the Zn-OX-ATZ material is a microporous material with pore sizes concentrated at 0.40 nm.

[0046] The Zn-OX-ATZ material obtained in Example 1 was subjected to adsorption experiments on carbon dioxide and nitrogen at 298K and 318K. The adsorption isotherms are shown in Figure 4. As can be seen from Figure 4, the Zn-OX-ATZ material exhibits rapid low-pressure adsorption of carbon dioxide, while showing very little adsorption of nitrogen, proving that the material preferentially adsorbs carbon dioxide.

[0047] The Zn-OX-ATZ material obtained in Example 1 was subjected to adsorption experiments on carbon dioxide / nitrogen (15 / 85, V / V) at 298K and 318K. The selectivity of carbon dioxide / nitrogen is shown in Figure 5. As can be seen from Figure 5, the carbon dioxide / nitrogen ratios for both exceeded 1000 at 1 bar, proving that the Zn-OX-ATZ adsorbent has excellent selectivity for carbon dioxide / nitrogen.

[0048] Example 2: This example synthesizes a metal-organic framework (MOF) material Zn-OX-ATZ. The specific preparation method is as follows: Zn(C2O4)·2H2O (0.1 mmol) and 3-amino-1,2,4-triazole (0.45 mmol) are ultrasonically dispersed in water (5 mL). The mixture is then transferred to a Teflon-lined reactor and placed in an oven at 150 °C for 3 days. The product is obtained by filtration and then washed five times with ethanol and water to remove unreacted salts and ligands, yielding crystalline Zn-OX-ATZ. The activated Zn-OX-ATZ is obtained by vacuum drying at 120 °C for 5 hours and can be used as an adsorbent.

[0049] Example 3: This example describes the synthesis of a metal-organic framework (MOF) material, Zn-OX-ATZ. The specific preparation method is as follows: 1 kg of zinc oxalate dihydrate and 5 kg of 3-amino-1,2,4-triazole were added to a large self-generated pressure reactor (30 L volume) containing 15 L of water. After stirring electrically for 50 minutes, the reaction was initiated in a 180 °C oven for 3 days. A white powder was obtained by centrifugation, followed by washing three times with water and ethanol to remove unreacted salts and ligands, yielding crystalline Zn-OX-ATZ. This crystalline Zn-OX-ATZ was then vacuum-dried at 180 °C for 5 hours to obtain activated Zn-OX-ATZ, which can be used as an adsorbent.

[0050] In this embodiment, the Zn-OX-ATZ compound was synthesized at the kilogram level, with stable production and consistent product quality.

[0051] Referring to Figure 2, which shows the X-ray diffraction patterns of the Zn-OX-ATZ materials obtained in Examples 1 to 3, it can be seen from Figure 2 that the powder X-ray diffraction patterns of the samples synthesized at different scales are highly consistent with the simulation patterns, proving that the synthesized samples have high purity and the products are stable after amplification.

[0052] Application Example 1: This application example uses Zn-OX-ATZ material as an adsorbent for adsorption (and desorption) tests to verify the high efficiency of Zn-OX-ATZ material in capturing carbon dioxide. The adsorption test conditions can be selected as a dry condition of 318K. Specifically, the Zn-OX-ATZ material obtained in Example 1 is loaded into an adsorption column (inner diameter 5 mm, volume 2 ml). Under a back pressure of 1 bar and 45°C, a two-component gas mixture of carbon dioxide and nitrogen (volume ratio of 15 / 85) is passed through the adsorption column at a flow rate of 4.0 mL / min. High-purity nitrogen (>99.9%) is detected at the tail end of the adsorption column. The test is stopped when carbon dioxide has completely permeated through. The adsorption column is purged with helium at 150°C to achieve cyclic regeneration; or it can be desorbed and regenerated at room temperature using a vacuum pump with a vacuum degree of 0.05 bar.

[0053] As can be seen from this embodiment, the Zn-OX-ATZ of the present invention, as an adsorbent, can selectively capture carbon dioxide in flue gas.

[0054] Application Example 2: This application example uses Zn-OX-ATZ material as the adsorbent for adsorption (and desorption) tests to verify the high efficiency of Zn-OX-ATZ material in capturing carbon dioxide. The adsorption (and desorption) test conditions can be selected as 318K and 70% RH. Specifically, the Zn-OX-ATZ material obtained in Example 1 is loaded into an adsorption column (5mm inner diameter, 2ml volume). Under 45℃ and 1 bar back pressure, a two-component gas mixture of carbon dioxide and nitrogen (volume ratio 15 / 85) is flowed through a steam generator at a flow rate of 4.0 mL / min. At this time, the humidity of the mixed gas is 70% RH. After passing through the adsorption column, high-purity nitrogen (>99.9%) is detected at the end of the adsorption column. The test is stopped when carbon dioxide has completely penetrated. The adsorption column is purged with helium at 150℃ to achieve cyclic regeneration. Alternatively, desorption regeneration can be performed at room temperature using a vacuum pump with a vacuum degree of 0.05 bar.

[0055] As can be seen from this embodiment, the Zn-OX-ATZ of the present invention, as an adsorbent, can still selectively capture carbon dioxide in flue gas under operating conditions of 318K and 70%RH.

[0056] Referring to Figure 6, (a) shows the dynamic breakthrough curves and cyclic dynamic breakthrough curves for Application Example 1 and Application Example 2 above; (b) shows the dynamic breakthrough curves for Application Example 1 and Application Example 2 under operating conditions of 318K, dryness, or 70% RH; and (c) shows the cyclic dynamic breakthrough curve for Application Example 2 under operating conditions of 318K and 70% RH. As shown in Figure 6, nitrogen preferentially exits the adsorption column compared to carbon dioxide. The retention time of carbon dioxide in the adsorption column exceeds 1 hour, and its performance remains stable during multiple cycles, confirming that Zn-OX-ATZ can be used as an adsorbent to achieve efficient capture of carbon dioxide in flue gas.

[0057] Application Example 3: This application example uses Zn-OX-ATZ material as an adsorbent to implement an adsorption process, verifying the high efficiency of Zn-OX-ATZ material in capturing carbon dioxide. The Zn-OX-ATZ material obtained in Example 3 was used as the adsorbent, and adsorption-desorption operations were performed using simulated industrial flue gas at 70% RH and a drying temperature of 318 K. Specifically, the Zn-OX-ATZ material obtained in Example 3 was loaded into an adsorption column (70 mm inner diameter, 1 L volume). Simulated flue gas, with the gas composition shown in Table 2, was passed through a steam generator at a flow rate of 1 L / min. The humidity of the mixed gas was 70% RH. The gas then passed through the adsorption column, and the carbon dioxide concentration was detected at the tail end of the column. When the carbon dioxide concentration at the tail end of the column reached the inlet concentration, the gas flow was stopped. The adsorption column was then purged with nitrogen at 180°C to achieve sample regeneration. When performing adsorption-desorption operations under dry conditions at 318 K, the test gas does not need to flow through the steam generator; other operations are the same or similar. Adsorption-desorption operations at 318 K and 70% RH were performed on various simulated flue gases shown in Table 2.

[0058] Table 2 Gas composition parameters of simulated industrial flue gas

[0059] In this embodiment, Zn-OX-ATZ is used as an adsorbent, which can selectively capture carbon dioxide in flue gas. The adsorbent is used to conduct carbon dioxide capture tests on simulated flue gas at kilogram-scale samples under operating conditions of 318K and 70%RH.

[0060] Referring to Figure 7, in Application Example 3, the dynamic breakthrough curves of simulated industrial flue gas at 318K (dry) and 70% RH are shown. Figure 7 demonstrates that the Zn-OX-ATZ material, under both dry and high humidity (70% RH) conditions at 318K, can achieve complete separation of carbon dioxide and nitrogen in simulated industrial flue gas, confirming its applicability for capturing carbon dioxide in flue gas under actual industrial conditions.

[0061] This invention synthesizes Zn-OX-ATZ and utilizes this compound to selectively capture carbon dioxide from flue gas, achieving one-step purification of flue gas. It is expected to replace the current energy-intensive organic amine-solution carbon dioxide absorption process and has great application potential in industrial flue gas purification.

[0062] In other embodiments, the Zn-OX-ATZ of the present invention is used as an adsorbent for the efficient capture of carbon dioxide, and can also be used to separate or treat other carbon dioxide-containing mixed gases besides flue gas. The adsorption method can be referred to in Application Embodiment 1 and Application Embodiment 2 above, and will not be repeated here.

[0063] In other embodiments, the metal-organic framework (MOF) Zn-OX-ATZ of the present invention is used as an adsorbent material, which has low cost and high stability. It can efficiently capture carbon dioxide from flue gas or other mixed gases through adsorption separation, thereby reducing carbon dioxide emissions. Using the Zn-OX-ATZ adsorbent material of the present invention, flue gas or other mixed gases can be separated or treated by adsorption separation (e.g., using the adsorption columns and adsorption-desorption conditions described in Application Examples 1 and 2 above), even under actual operating conditions of 318±50K and 0-70%RH, carbon dioxide can still be efficiently captured from flue gas or other mixed gases.

[0064] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A pillar-supported metal-organic framework material with the molecular formula C6H6N8O5Zn2 is generated by reacting ZnOX-zinc oxalate dihydrate Zn(C2O4)·2H2O as a metal salt source with ATZ-3-amino-1,2,4-triazole as an organic ligand under a hydrothermal environment to form the compound Zn-OX-ATZ, wherein Zn-OX-ATZ is a crystalline material.

2. The column-supported metal-organic framework material as described in claim 1, characterized in that: The molecular structure of the compound Zn-OX-ATZ includes Zn as a structural unit. 2+ ATZ and C2O4 2- Among them, Zn 2+ It combines with three N atoms from different ATZs to form planar layers, and the different planar layers are connected by C2O4. 2- Connecting is performed, where C2O4 2- The four oxygen atoms are respectively bonded to two different layers of Zn 2+ Ions linked together.

3. The column-supported metal-organic framework material as described in claim 2, characterized in that: The molecular coordination mode of the compound Zn-OX-ATZ is as follows: The structural units of the compound Zn-OX-ATZ coordinate with each other to construct a three-dimensional structure of Zn-OX-ATZ, which is as follows:

4. The column-supported metal-organic framework material according to any one of claims 1 to 3, characterized in that: The crystal structure of the compound Zn-OX-ATZ has one-dimensional channels; the BET specific surface area of ​​Zn-OX-ATZ is 303.3 cm². 2 / g; the pore volume of the Zn-OX-ATZ is 0.15cm³. 3 / g; the pore size distribution of the Zn-OX-ATZ is concentrated in The pores contain -NH2 groups, which can generate a stronger interaction with carbon dioxide, thus enabling the capture of carbon dioxide from the flue gas.

5. The column-supported metal-organic framework material as described in claim 4, characterized in that: The crystallographic parameters of the compound Zn-OX-ATZ are:

6. A method for preparing pillar-supported metal-organic framework materials, comprising the following steps: Step S1, prepare the reaction system: Disperse zinc oxalate dihydrate Zn(C2O4)·2H2O and 3-amino-1,2,4-triazole in a solvent to form a homogeneous mixture; Step S2: The synthesis reaction is carried out under hydrothermal conditions to obtain a product containing Zn-OX-ATZ; Step S3: Separate and purify the product containing Zn-OX-ATZ to obtain Zn-OX-ATZ crystalline material; The Zn-OX-ATZ is the column-supported metal-organic framework material as described in any one of claims 1 to 5.

7. The preparation method according to claim 6, characterized in that: In step S1: The solvent is water; The molar ratio of zinc oxalate dihydrate to 3-amino-1,2,4-triazole is 1:3 to 6; The ratio of zinc oxalate dihydrate to solvent is 3-8 mL of solvent per 1 mmol of zinc oxalate dihydrate; In step S2, the reaction temperature under hydrothermal conditions is 150-190℃.

8. The preparation method according to claim 6, characterized in that: The preparation method further includes: Step S4: Activate the Zn-OX-ATZ crystalline material obtained in step S3 to obtain the adsorbent material; The activation temperature is 120-180℃.

9. An adsorbent made of the pillar-type metal-organic framework material according to any one of claims 1 to 5, for capturing carbon dioxide.

10. The adsorbent as described in claim 9, characterized in that: The adsorbent is used to selectively capture carbon dioxide from flue gas through physical adsorption, thereby purifying the flue gas. The adsorption temperature of the physical adsorption method is 0–60°C, the adsorption pressure is 0–3 bar, the desorption temperature is 50–180°C, and the desorption pressure is 0.01–1.0 bar. The physical adsorption method uses an adsorption column.

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