Metal organic framework material, preparation method and application thereof

Abstract

The application belongs to the technical field of chemical separation, and particularly relates to a metal organic framework material and a preparation method and application thereof. 2‑ As an anion-pillared, the metal cation is used as a node, and a new type of metal organic framework (MOFs) adsorbent is formed by self-assembly coordination. The pore of the metal organic framework material prepared has super-strong negative static potential, thereby showing super-strong capturing force on acetylene, and showing weak capturing capacity on CO2 and C2H4. Based on the capturing difference of different gas components, the metal organic framework material prepared by the application can efficiently capture C2H2 from C2H2 / C2H4 or C2H2 / CO2 binary mixed gas, and further desorption from the adsorption material rich in C2H2, so as to prepare a high-purity C2H2 product.

Description

Technical Field

[0001] This invention belongs to the field of chemical separation technology, specifically relating to a metal-organic framework material, its preparation method, and its application. Background Technology

[0002] Gaseous light hydrocarbons are crucial chemical raw materials in chemical synthesis, making their separation essential. C2H4, a bulk chemical product, inevitably contains trace amounts of C2H2 during production, which can poison the polymerization reaction of C2H4. Existing cryogenic distillation techniques struggle to separate the small amounts of C2H2 from C2H4, and commonly used solvent absorption methods pose significant environmental hazards and are difficult to regenerate. C2H2 is a vital chemical commodity widely used in the manufacture of vinyl and acrylate polymers. Industrially, C2H2 is typically produced through the partial oxidative cracking of natural gas, a process that does not generate a proportional amount of CO2; however, both molecules share the same kinetic diameter. Both C2H2 and CO2 share similar physical properties (boiling points: C2H2, 189.3 K; CO2, 194.7 K). This makes the separation of C2H2 / CO2 extremely difficult. Traditional cryogenic distillation techniques require low temperatures, high pressures, high trays, high reflux ratios, and high energy consumption. Therefore, finding a separation technology with relatively low energy consumption and simple equipment is of great significance.

[0003] Adsorption separation technology boasts advantages such as low energy consumption, high efficiency, high product purity, and simple processes, showing promising prospects for industrial applications. Metal-organic frameworks (MOFs), as a new generation of porous materials, possess advantages such as high porosity, highly designable pore structures, and uniform pore size, demonstrating strong potential in the field of adsorption separation. However, the pores of two-dimensional anion exchange column MOFs exhibit significant flexibility, affecting the adsorption and diffusion of C2H2. Achieving selective and efficient capture of C2H2 in binary mixtures of C2H2 / C2H4 or C2H2 / CO2 presents a significant challenge for researchers, especially for the separation of C2H2 and CO2 with similar physical properties, and the removal of trace amounts of C2H2 is even more difficult. Therefore, this invention provides a metal-organic framework material, its preparation method, and its applications. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a metal-organic framework material, its preparation method, and its applications, using 4,4-bipyridyl disulfide as the organic ligand and octahedral SnF6. 2-As an anion pillar, and with divalent transition metal cations as metal nodes, a novel metal-organic framework (MOF) adsorbent is formed through self-assembly. This enables the efficient capture of acetylene in binary gas mixtures of C2H2 / C2H4 or C2H2 / CO2, producing high-purity acetylene products that are stably applicable to the adsorption and separation of gaseous light hydrocarbons in industry.

[0005] The present invention solves the above-mentioned technical problems through the following technical solutions.

[0006] The first objective of this application is to provide a method for preparing a metal-organic framework material, comprising the following steps:

[0007] Divalent transition metal cations, 4,4-bipyridyl disulfide, and octahedral SnF6 2- Dissolved in a solvent, the reaction is carried out at 10–80°C with stirring or standing. After filtration, washing, and vacuum activation, metal-organic framework materials are obtained.

[0008] Preferably, the divalent transition metal cation, 4,4-bipyridyl disulfide, and octahedral SnF6 2- The molar ratio is 1:1 to 10:1 to 20.

[0009] Preferably, the solvent is methanol or ethanol, the vacuum activation temperature is 333K, and the time is 6h.

[0010] A second objective of this invention is to provide a metal-organic framework material prepared by the above-described method, wherein, when the solvent is methanol, the metal-organic framework material has the structural formula SnFSIX-dpds-M-2D, where M is a metal cation, dpds is 4,4-bipyridyl disulfide, and SnFSIX is octahedral SnF6. 2- 2D indicates that the metal-organic framework material is a two-dimensional layered structure.

[0011] A third objective of this invention is to provide a metal-organic framework material prepared by the above-described method, wherein when the solvent is ethanol, the metal-organic framework material is named SnFSIX-dpds-M-3D, where M is a metal cation, dpds is 4,4-bipyridyl disulfide, and SnFSIX is octahedral SnF6. 2- 3D refers to the metal-organic framework material having a three-dimensional SQC5 structure.

[0012] Preferably, the divalent transition metal cation is Zn. 2+ Cu 2+ Co 2+ Ni 2+ or Cd 2+ .

[0013] The fourth objective of this invention is to provide an application of the above-mentioned metal-organic framework material in the selective adsorption and separation of alkynes in a mixed gas, wherein the metal-organic framework material is used as an adsorbent to contact the mixed gas containing alkynes for adsorption and separation.

[0014] Preferably, after the metal-organic framework material selectively adsorbs alkynes, it repels the remaining gases in the mixed gas. After the adsorption is saturated, the alkyne gas is obtained by helium purging or vacuum desorption.

[0015] Preferably, the mixed gas is C2H2 / C2H4 or C2H2 / CO2, wherein the volume ratio of C2H2 to C2H4 in the C2H2 / C2H4 mixed gas is 1:99 to 99:1; and the volume ratio of C2H2 to CO2 in the C2H2 / CO2 mixed gas is 1:99 to 99:1.

[0016] Preferably, the adsorption temperature is -50 to 100°C, the adsorption pressure is 0 to 10 bar, the desorption temperature is 25 to 150°C, and the desorption pressure is 0 to 1.0 bar.

[0017] The contact method described in this invention is fixed-bed adsorption, fluidized-bed adsorption, or moving-bed adsorption; the contact adsorption process is one or more combinations of single-tower or multi-tower pressure swing adsorption, temperature swing adsorption, and vacuum desorption adsorption.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] (1) In this invention, 4,4-bipyridyl disulfide, which has strong aromatic properties, is used as the organic ligand and octahedral SnF6. 2- As an anion-supported structure, a novel metal-organic framework (MOF) adsorbent is formed by self-assembly using metal cations as nodes. Due to the strong negative electrostatic potential of the pores of the prepared MOF material, it exhibits a strong capture capacity for acetylene, while showing a weaker capture capacity for carbon dioxide (CO2) and ethylene (C2H4). Based on the above differences in the capture of different gas components, the MOF material prepared in this invention achieves the goal of efficiently capturing C2H2 from C2H2 / C2H4 or C2H2 / CO2 binary gas mixtures, and further desorbing it from the C2H2-enriched adsorbent material, thereby producing a high-purity C2H2 product.

[0020] (2) The metal-organic framework material prepared by this invention has the ability to precisely control the pore size and the flexible and controllable pore environment. When it comes into contact with unsaturated carbon-carbon bonds, the framework will respond by opening the gate and adaptively opening to a suitable window size to allow alkyne molecules to enter the pore. When the alkyne opens the internal pore of the adsorbent, the pore reaches a suitable pore size, and is supplemented by benzene rings and functional anionic octahedral SnF6 in the pore.2- Selective adsorption of alkynes was achieved, repelling other gas molecules in the mixed gas inside the pores, thus realizing the efficient separation of binary mixed components of C2H2 / C2H4 and C2H2 / CO2.

[0021] (3) The metal-organic framework material prepared by the present invention has excellent cycling performance in simulating actual mixed gas components. It has high selectivity for separating alkynes from mixed gases, excellent breakthrough cycle stability and solvent stability, good thermal stability and ultra-high production of high-purity acetylene. It can be stably applied to the adsorption and separation of gaseous light hydrocarbons in industry and is expected to replace traditional solvent extraction or low-temperature distillation technology. Attached Figure Description

[0022] Figure 1 This is an image of the synthesized powder of the SnFSIX-dpds-Cu-2D material obtained in Example 1 of this invention;

[0023] Figure 2 Image of the synthesized powder of SnFSIX-dpds-Cu-3D material obtained in Example 2 of this invention;

[0024] Figure 3 The X-ray diffraction results of the SnFSIX-dpds-Cu-2D material obtained in Example 1 of this invention are shown below.

[0025] Figure 4 The X-ray diffraction results of the SnFSIX-dpds-Cu-3D material obtained in Example 2 of this invention are shown.

[0026] Figure 5 The thermogravimetric curve test results of the SnFSIX-dpds-Cu-2D material obtained in Example 1 of this invention;

[0027] Figure 6 The thermogravimetric curve test results of the SnFSIX-dpds-Cu-3D material obtained in Example 2 of this invention;

[0028] Figure 7 The 195K CO2 adsorption isotherm of the SnFSIX-dpds-Cu-2D material obtained in Example 1 of this invention;

[0029] Figure 8 The 195K CO2 adsorption isotherm of the SnFSIX-dpds-Cu-3D material obtained in Example 2 of this invention;

[0030] Figure 9 The adsorption isotherms of SnFSIX-dpds-Cu-2D material obtained in Example 1 of this invention for C2H2, CO2 and C2H4 at 298K.

[0031] Figure 10 The adsorption isotherms of SnFSIX-dpds-Cu-3D material obtained in Example 1 of this invention for C2H2, CO2 and C2H4 at 298K.

[0032] Figure 11 The dynamic breakthrough curve of the SnFSIX-dpds-Cu-2D material obtained in Example 1 of this invention under C2H2 / CO2 mixed gas composition (volume ratio 1:1, flow rate 2.0 mL / min) at 298 K.

[0033] Figure 12 The dynamic breakthrough curve of the SnFSIX-dpds-Cu-3D material obtained in Example 2 of this invention under C2H2 / CO2 mixed gas composition (volume ratio 1:1, flow rate 2.0 mL / min) at 298 K.

[0034] Figure 13 The curve of C2H2 desorption after dynamic penetration experiment of SnFSIX-dpds-Cu-2D material obtained in Example 1 of this invention (volume ratio 1:1, flow rate 2.0 mL / min) at 298 K (helium flow rate 10.0 mL / min).

[0035] Figure 14 The curve of C2H2 desorption after dynamic penetration experiment of SnFSIX-dpds-Cu-3D material obtained in Example 2 of this invention (volume ratio 1:1, flow rate 2.0 mL / min) at 298 K (helium flow rate 10.0 mL / min).

[0036] Figure 15 The curve shows the dynamic breakthrough process of the SnFSIX-dpds-Cu-2D material obtained in Example 1 of this invention under C2H2 / C2H4 mixed gas components (volume ratio 1:99, flow rate 2.0 mL / min) at 298 K.

[0037] Figure 16 The curve shows the dynamic breakthrough process of the SnFSIX-dpds-Cu-3D material obtained in Example 2 of this invention under C2H2 / C2H4 mixed gas components (volume ratio 1:99, flow rate 2.0 mL / min) at 298 K.

[0038] Figure 17 This is a schematic diagram of the structure of the SnFSIX-dpds-Cu-2D metal-organic framework material in Embodiment 1 of the present invention;

[0039] Figure 18This is a schematic diagram of the structure of the SnFSIX-dpds-Cu-3D metal-organic framework material in Embodiment 2 of the present invention;

[0040] Figure 19 This is a schematic diagram of the synthesis route and structure of the metal-organic framework materials in Examples 1 and 2 of the present invention. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] It should be noted that the technical terms used in this invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of this invention. Unless otherwise specified, all raw materials, reagents, instruments and equipment used in the following embodiments of this invention can be purchased from the market or prepared by existing methods.

[0043] Example 1

[0044] A method for preparing a metal-organic framework material includes the following steps:

[0045] 1 mmol anhydrous copper nitrate, 1 mmol ammonium hexafluorostannate, and 2 mmol 4,4'-bipyridine disulfide were dissolved in 30 mL of methanol and stirred at 298 K for 12 h. The resulting slurry was filtered, washed, and then activated under vacuum at 333 K for 6 h to obtain SnFSIX-dpds-Cu-2D material. The powder image of the synthesized SnFSIX-dpds-Cu-2D metal-organic framework material is shown below. Figure 1 As shown in the diagram, the structural schematic of the SnFSIX-dpds-Cu-2D metal-organic framework material is as follows: Figure 17 As shown, the synthesis route is as follows Figure 19 As shown.

[0046] This invention also utilizes other metal cations to prepare two-dimensional metal framework materials, specifically:

[0047] 1. Dissolve 1 mmol of anhydrous nickel nitrate, 1 mmol of ammonium hexafluorostannate, and 2 mmol of 4,4'-bipyridine disulfide in 30 mL of methanol. Stir at 298 K for 12 h. After filtration and washing, the resulting slurry is activated at 333 K under vacuum for 6 h to obtain SnFSIX-dpds-Ni-2D material.

[0048] 2. Dissolve 1 mmol of anhydrous cadmium nitrate, 1 mmol of ammonium hexafluorostannate, and 2 mmol of 4,4'-bipyridine disulfide in 30 mL of methanol. Stir at 298 K for 12 h. After filtration and washing, the resulting slurry is activated at 333 K under vacuum for 6 h to obtain SnFSIX-dpds-Cd-2D material.

[0049] 3. Dissolve 1 mmol of anhydrous zinc nitrate, 1 mmol of ammonium hexafluorostannate, and 2 mmol of 4,4'-bipyridine disulfide in 30 mL of methanol. Stir at 298 K for 12 h at room temperature. After filtration and washing, the resulting slurry is activated at 333 K under vacuum for 6 h to obtain SnFSIX-dpds-Zn-2D material.

[0050] 4. Dissolve 1 mmol of anhydrous cobalt nitrate, 1 mmol of ammonium hexafluorostannate, and 2 mmol of 4,4'-bipyridine disulfide in 30 mL of methanol. Stir at 298 K for 12 h. After filtration and washing, the resulting slurry is activated at 333 K under vacuum for 6 h to obtain SnFSIX-dpds-Co-2D material.

[0051] The four two-dimensional metal framework materials with different metal cations prepared above have similar performance to the SnFSIX-dpds-Cu-2D metal-organic framework material of Example 1. The performance analysis and explanation below will only take Example 1 as an example.

[0052] Figure 3 This is the X-ray diffraction pattern of the SnFSIX-dpds-Cu-2D material in Example 1 of the present invention. Figure 3 As shown, the XRD characteristic peaks of the SnFSIX-dpds-Cu-2D material product in Example 1 correspond well with the XRD characteristic peaks of the simulated standard curve, indicating that the anionic SnF6 prepared in this invention... 2- The purity of column-supported metal-organic framework materials is relatively high.

[0053] Figure 5 This is the thermogravimetric curve of the SnFSIX-dpds-Cu-2D material in Example 1 of the present invention. Figure 5 As shown, the thermogravimetric curve of the SnFSIX-dpds-Cu-2D material in Example 1 presents a stepped curve, with inflection points of mass reduction at 100℃ and 240℃. After the temperature exceeds 100℃, the SnFSIX-dpds-Cu-2D material will experience a small mass reduction, which is due to the removal of water and air from the pores. After the temperature exceeds 240℃, the framework begins to collapse, and the internal structure is damaged due to the high temperature, indicating that the thermal stability of the SnFSIX-dpds-Cu-2D material in Example 1 is relatively very good.

[0054] The pore structure of the SnFSIX-dpds-Cu-2D metal-organic framework material in Example 1 of this invention was characterized by testing the carbon dioxide adsorption isotherm of the flexible novel anionic metal-organic framework material. The test conditions were as follows: the CO2 gas adsorption-desorption isotherm was measured on an ASAP2460. Before analysis, the sample was degassed at room temperature for 24 hours to remove guest molecules from the pores. The experimental temperature was maintained using dry ice at 195 K. Figure 7 This is the CO2 adsorption isotherm of the SnFSIX-dpds-Cu-2D material at 195 K in Example 1 of this invention. Figure 7 As shown, the surface area of ​​SnFSIX-dpds-Cu-2D, calculated from CO2 adsorption at 195 K, is 272.95 m². 2 / g, pore volume is 0.243cm³ 3 / g.

[0055] Example 2

[0056] A method for preparing a metal-organic framework material includes the following steps:

[0057] 1 mmol anhydrous copper nitrate, 1 mmol ammonium hexafluorostannate, and 2 mmol 4,4'-bipyridine disulfide were dissolved in 30 mL of ethanol and stirred at 298 K for 12 h. The resulting slurry was filtered, washed, and then activated under vacuum at 333 K for 6 h to obtain SnFSIX-dpds-Cu-3D material. The powder image of the synthesized SnFSIX-dpds-Cu-3D metal-organic framework material is shown below. Figure 2 As shown in the diagram. A schematic diagram of the structure of the SnFSIX-dpds-Cu-3D metal-organic framework material is shown below. Figure 18 As shown, the synthesis route is as follows Figure 19 As shown.

[0058] This invention also utilizes other metal cations to prepare three-dimensional metal framework materials, specifically:

[0059] 1. Dissolve 1 mmol of anhydrous nickel nitrate, 1 mmol of ammonium hexafluorostannate, and 2 mmol of 4,4'-bipyridine disulfide in 30 mL of ethanol. Stir at 298 K for 12 h. After filtration and washing, the resulting slurry is activated at 333 K under vacuum for 6 h to obtain SnFSIX-dpds-Ni-3D material.

[0060] 2. Dissolve 1 mmol of anhydrous cadmium nitrate, 1 mmol of ammonium hexafluorostannate, and 2 mmol of 4,4'-bipyridine disulfide in 30 mL of ethanol. Stir at 298 K for 12 h at room temperature. After filtration and washing, the resulting slurry is activated at 333 K under vacuum for 6 h to obtain SnFSIX-dpds-Cd-3D material.

[0061] 3. Dissolve 1 mmol of anhydrous zinc nitrate, 1 mmol of ammonium hexafluorostannate, and 2 mmol of 4,4'-bipyridine disulfide in 30 mL of ethanol. Stir at 298 K for 12 h at room temperature. After filtration and washing, the resulting slurry is activated at 333 K under vacuum for 6 h to obtain SnFSIX-dpds-Zn-3D material.

[0062] 4. Dissolve 1 mmol of anhydrous cobalt nitrate, 1 mmol of ammonium hexafluorostannate, and 2 mmol of 4,4'-bipyridine disulfide in 30 mL of ethanol. Stir at 298 K for 12 h at room temperature. After filtration and washing, the resulting slurry is activated at 333 K under vacuum for 6 h to obtain SnFSIX-dpds-Co-3D material.

[0063] The four two-dimensional metal framework materials with different metal cations prepared above have similar performance to the SnFSIX-dpds-Cu-3D metal-organic framework material of Example 2. The performance analysis and explanation below will only take Example 2 as an example.

[0064] Figure 4 This is the X-ray diffraction pattern of the SnFSIX-dpds-Cu-3D material in Example 2 of the present invention. Figure 4 As shown, the XRD characteristic peaks of the SnFSIX-dpds-Cu-3D material product in Example 2 correspond well with the XRD characteristic peaks of the simulated standard curve, indicating that the anionic SnF6 prepared in this invention... 2- The purity of column-supported metal-organic framework materials is relatively high.

[0065] Figure 6 This is the thermogravimetric curve of the SnFSIX-dpds-Cu-3D material in Example 1 of the present invention. Figure 6 As shown, the thermogravimetric curve of the SnFSIX-dpds-Cu-3D material in Example 2 presents a stepped curve, with inflection points of mass reduction at 100℃ and 240℃. After the temperature exceeds 100℃, the SnFSIX-dpds-Cu-3D material will experience a small mass reduction, which is due to the removal of water and air from the pores. After the temperature exceeds 240℃, the framework begins to collapse, and the internal structure is damaged due to the high temperature, indicating that the thermal stability of the SnFSIX-dpds-Cu-3D material in Example 1 is relatively very good.

[0066] The pore structure of the SnFSIX-dpds-Cu-3D metal-organic framework material in Example 2 of this invention was characterized by testing the carbon dioxide adsorption isotherm of the flexible novel anionic metal-organic framework material. The test conditions were as follows: the CO2 gas adsorption-desorption isotherm was measured on an ASAP2460. Before analysis, the sample was degassed at room temperature for 24 hours to remove guest molecules from the pores. The experimental temperature was maintained using dry ice at 195 K. Figure 8 This is the CO2 adsorption isotherm of the SnFSIX-dpds-Cu-3D material at 195 K in Example 2 of this invention. Figure 8 As shown, the pore capacity of the SnFSIX-dpds-Cu-3D material, calculated from CO2 adsorption at 195 K, is 0.236 cm³. 3 / g, specific surface area is 424.1m² 2 / g.

[0067] Example 3

[0068] The SnFSIX-dpds-Cu-2D and SnFSIX-dpds-Cu-3D materials prepared in Examples 1 and 2 were respectively packed into fixed-bed adsorption columns with an inner diameter of 6 mm and a length of 15 cm. At 298 K and 1 bar, a C2H2 / CO2 (50:50) mixed gas was flowed through the adsorption column at a fixed flow rate of 2.0 mL / min. The mixed gas containing C2H2 and CO2 entered the fixed-bed adsorption column packed with metal-organic framework material. The CO2 component preferentially penetrated the bed, and high-purity CO2 gas (>99.9%) was obtained at the tail end of the gas adsorption column. Adsorption was stopped when the adsorption column was completely penetrated. The adsorption column was regenerated by purging with helium at room temperature, yielding high-purity C2H2 gas (>99.5%) during regeneration; alternatively, desorption regeneration was performed at room temperature using a vacuum pump with a vacuum degree of 0.05 bar.

[0069] Example 4

[0070] The SnFSIX-dpds-Cu-2D and SnFSIX-dpds-Cu-3D materials prepared in Examples 1 and 2 were respectively packed into fixed-bed adsorption columns with an inner diameter of 6 mm and a length of 15 cm. At 298 K and 1 bar, a C2H2 / C2H4 (50:50) mixed gas was flowed through the adsorption column at a fixed flow rate of 2.0 mL / min. The mixed gas containing C2H2 and C2H4 entered the fixed-bed adsorption column packed with metal-organic framework material. The C2H4 component preferentially penetrated the bed, and high-purity C2H4 gas (>99.9%) was obtained at the tail end of the gas adsorption column. Adsorption was stopped when the adsorption column was completely penetrated. The adsorption column was regenerated by purging with helium at room temperature, yielding high-purity C2H2 gas (>99.5%) during regeneration; alternatively, desorption regeneration was performed at room temperature using a vacuum pump with a vacuum degree of 0.05 bar.

[0071] Examples 5-6

[0072] The difference from Example 3 is that the fixed flow rate of 2.0 mL / min was replaced with 3.0 mL / min and 5.0 mL / min, respectively.

[0073] Examples 7-8

[0074] The difference from Example 4 is that the fixed flow rate of 2.0 mL / min was replaced with 3.0 mL / min and 5.0 mL / min, respectively.

[0075] Figure 9 and Figure 10 The isothermal adsorption curves of C2H2, C2H4, and CO2 at 298 K for the SnFSIX-dpds-Cu-2D material of Example 1 and the SnFSIX-dpds-Cu-3D material of Example 2 of this invention are shown below. Figure 9 and Figure 10 As shown, the isothermal adsorption curve of acetylene in SnFSIX-dpds-Cu-2D is an open-gate process. At low pressures (p < 0.05 bar), adsorption rapidly saturates. Within the pressure range of 0.05 bar to 0.6 bar, the SnFSIX-dpds-Cu-2D material framework gradually opens, and the adsorption increases slowly until saturation, indicating that the material possesses a two-dimensional flexible framework. The isothermal adsorption curve of acetylene in SnFSIX-dpds-Cu-3D is a rapid saturation process at low pressure, without obvious flexible characteristics, indicating that the material possesses a three-dimensional rigid framework.

[0076] Figure 11 and Figure 12The figures show the dynamic penetration curves of the SnFSIX-dpds-Cu-2D material from Example 1 and the SnFSIX-dpds-Cu-3D material from Example 2 of this invention, respectively, against a C2H2 / CO2 mixed gas with a volume ratio of 1:1 at 298K. Figure 11 and Figure 12 As shown, both SnFSIX-dpds-Cu-2D and SnFSIX-dpds-Cu-3D materials exhibited preferential CO2 effluent penetration through the column, followed by acetylene effluent. The difference lies in the fact that SnFSIX-dpds-Cu-2D material showed a faster effluent velocity over 20 minutes. -1 CO2 flows out from both sides, 52 min g -1 C2H2 flows out from both sides, with a breakthrough time of 32 min g. -1 SnFSIX-dpds-Cu-3D material at 28 min g -1 CO2 outflow, 73 min g -1 C2H2 flows out, with a breakthrough time of 45 min g. -1 .

[0077] Figure 13 and Figure 14 The figures show the C2H2 desorption process curves after dynamic penetration experiments of the SnFSIX-dpds-Cu-2D material (Example 1) and the SnFSIX-dpds-Cu-3D material (Example 2) at 298 K with a C2H2 / CO2 mixed gas of a volume ratio of 1:1. Figure 13 and Figure 14 As shown, the desorption process involved purging at room temperature for approximately 30 minutes, followed by heating to 70°C, with a helium flow rate of 10 mL / min. -1 Both SnFSIX-dpds-Cu-2D and SnFSIX-dpds-Cu-3D materials can collect purified acetylene. However, the SnFSIX-dpds-Cu-3D material yields high-purity acetylene (>99.5%), with a yield of 1.88 mmol g. -1 SnFSIX-dpds-Cu-2D can only produce 90%-98% acetylene.

[0078] Figure 15 and Figure 16 The figures show the dynamic penetration curves of the SnFSIX-dpds-Cu-2D material (Example 1) and the SnFSIX-dpds-Cu-3D material (Example 2) of this invention, respectively, through a C2H2 / C2H4 mixed gas with a volume ratio of 1:99 at 298 K. Figure 15 and 16As shown, both SnFSIX-dpds-Cu-2D and SnFSIX-dpds-Cu-3D materials exhibit preferential ethylene efflux through the column. The difference lies in the efflux rate of SnFSIX-dpds-Cu-2D at 256 min g. -1 Trace amounts of acetylene (>1 ppm) were detected immediately, with a yield of 22.1 mmol g. -1 SnFSIX-dpds-Cu-3D at 996 min g -1 Only trace amounts of acetylene were detected, with a yield of 86.1 mmol g. -1 .

[0079] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described here to avoid redundancy. Although preferred embodiments of the invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this invention.

[0080] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for preparing a metal-organic framework material, characterized in that, Includes the following steps: Divalent transition metal cations, 4,4-bipyridyl disulfide, and octahedral SnF6 2- Dissolved in ethanol, reacted by stirring or standing at 10-80℃, filtered, washed, and then vacuum activated to obtain a metal-organic framework material; the vacuum activation temperature was 333 K and the time was 6 h; the metal-organic framework material is three-dimensional. sqc5 structure; The divalent transition metal cation, 4,4-bipyridyl disulfide, and octahedral SnF6 2- The molar ratio is 1:1~10:1~20; The divalent transition metal cation is Zn. 2+ Cu 2+ Co 2+ Ni 2+ or Cd 2+ .

2. The metal-organic framework material prepared by the preparation method according to claim 1.

3. The application of the metal-organic framework material according to claim 2 in the selective adsorption and separation of alkynes in a mixed gas, characterized in that, Using the metal-organic framework material as an adsorbent, it is contacted with a mixed gas containing alkynes for adsorption and separation. After selectively adsorbing alkynes, the metal-organic framework material repels the remaining gases in the mixed gas. After adsorption saturation, the alkyne gas is obtained by helium purging or vacuum desorption.

4. The application according to claim 3, characterized in that, The mixed gas is C2H2 / C2H4 or C2H2 / CO2, wherein the volume ratio of C2H2 to C2H4 in the C2H2 / C2H4 mixed gas is 1:99~99:1; and the volume ratio of C2H2 to CO2 in the C2H2 / CO2 mixed gas is 1:99~99:

1.

5. The application according to claim 3, characterized in that, The adsorption temperature is -50~100℃, and the adsorption pressure is 0~10 bar; the desorption temperature is 25~150℃, and the desorption pressure is 0~1.0 bar.

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