C5F 10 O mixed gas decomposition component adsorption material and preparation method and application thereof

Abstract

The present invention discloses a C5F 10 O mixed gas decomposition component adsorption material and its preparation method and application. The adsorption material is prepared by spraying and doping a metal organic framework material uniformly dispersed on a nanofiber membrane obtained by electrospinning technology to adsorb C5F 10 The adsorption material provided by the present invention utilizes a metal-organic framework / nanofiber composite membrane to decompose components of mixed gases. The composite membrane formed by the synergistic combination of a metal-organic framework material and a porous nanofiber membrane substrate has a larger specific surface area and more metal active sites, promoting the adsorption of gas molecules and facilitating their penetration and diffusion, thereby significantly improving the gas sensitivity and adsorption effect of the adsorption material.

Description

Technical Field

[0001] The present invention belongs to the technical field of adsorption materials, and specifically relates to a method for adsorbing C5F 10 Adsorption material for the decomposition components of O mixed gas hexafluoropropylene and carbon tetrafluoride. Background Art

[0002] Sulfur hexafluoride (SF6) is an insulating gas commonly used in the power industry, with excellent insulation and arc extinguishing properties. However, SF6 is also a gas with a strong greenhouse effect, and its use is explicitly restricted by the provisions of the Kyoto Protocol and the Paris Agreement. In order to reduce the power system's dependence on SF6, experts and scholars in the industry have begun to look for new environmentally friendly gases as insulating media for use in power systems. Among them, perfluoropentanone (C5F 10 As a new type of environmentally friendly insulating gas, O) has an insulation performance 1.4 times that of SF6, stable chemical properties, a GWP value of about 1, and an atmospheric life of only 15 days, and its impact on the environment is far less than SF6.

[0003] In order to meet the different liquefaction temperature requirements in engineering application environments, C5F 10 In actual operation, O2 is often mixed with CO2. However, under long-term high-voltage operation, discharge or overheating may occur inside the equipment, directly causing C5F 10 O mixed gas decomposes to varying degrees and reacts with trace oxygen and moisture to form decomposition products such as octafluoropropane (C3F8), carbon tetrafluoride (CF4), hexafluoropropylene (C3F6) and carbonyl fluoride (COF2), resulting in C5F 10 The insulation strength of O gas decreases, which endangers the stability of the power system. Moreover, if these toxic gases are directly discharged into the atmosphere, they will also pose a threat to human health. Therefore, in order to ensure the long-term operation of the equipment, the C5F 10 The waste gas treatment of the decomposition components of the O mixed gas is crucial.

[0004] At present, the adsorption materials used in the power industry are mainly metal oxides (such as activated alumina), activated carbon (fiber), zeolite / carbon molecular sieve, etc. However, there are a series of problems such as insufficient adsorption effect, which leads to the decline of gas dielectric insulation performance and the increase of equipment footprint, which cannot meet the current adsorption requirements of C5F 10 Requirements for the use of O mixed gas decomposition components C3F6 and CF4. Summary of the Invention

[0005] In order to solve the above-mentioned technical problems, one of the purposes of the present invention is to provide a method for 10 O mixed gas decomposition components C3F6 and CF4 have better adsorption effect of adsorption materials.

[0006] The second object of the present invention is to provide a C5F 10 Preparation method of adsorption material for decomposition components of O mixed gas.

[0007] The third object of the present invention is to provide a C5F 10 Application of adsorption materials for decomposition components of O mixed gases.

[0008] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a C5F 10 O mixed gas decomposition component adsorption material, the adsorption material is prepared by uniformly dispersing the metal organic framework material on the nanofiber membrane obtained by electrospinning technology through spray doping method, and is used for adsorbing C5F 10 Metal-organic framework / nanofiber composite membranes for decomposition of O mixed gases.

[0009] Furthermore, 2.3 to 2.8 mg of the metal organic framework material is sprayed on each square centimeter of the nanofiber membrane.

[0010] Furthermore, the metal organic framework material includes HKUST-1(Cu) or HKUST-1(Zn).

[0011] Furthermore, the nanofiber membrane includes a polyacrylonitrile nanofiber membrane, a polylactic acid nanofiber membrane, a polyvinyl alcohol nanofiber membrane, a polyimide nanofiber membrane or a polymethyl methacrylate nanofiber membrane.

[0012] A C5F 10 The preparation method of the adsorption material of the decomposition component of the O mixed gas comprises the following steps:

[0013] Preparation of nanofiber membranes by electrospinning: A high molecular weight polymer is dissolved in an organic solvent, and the mixture is stirred continuously for 4 to 5 hours in a closed water bath at a temperature of 50 to 80°C to obtain an electrospinning precursor solution with a mass percent concentration of 5 to 15%. The nanofiber membranes are prepared by electrospinning.

[0014] Preparation of metal organic framework / nanofiber composite membrane by spray doping method: the metal organic framework material is mixed with the organic solvent, stirred at room temperature for 0.5 to 1 hour, and then ultrasonically dispersed in an ice bath for 2 to 3 hours to obtain a dispersion; the dispersion is loaded into a pneumatic spray gun for spraying, so that the dispersion is evenly sprayed back and forth on the surface of the nanofiber membrane. After spraying, it is placed in an oven at 80 to 85°C for drying for 12 to 14 hours to obtain a metal organic framework / nanofiber composite membrane.

[0015] Furthermore, in the step of preparing the nanofiber membrane using electrospinning technology, the polymer includes polyacrylonitrile (PAN), polylactic acid (PLA), polyvinyl alcohol, polyimide, or polymethyl methacrylate. The organic solvent is selected from N,N-dimethylformamide (DMF) and chloroform. The conditions of the electrospinning technology are: voltage of 15 to 25 kV, receiving distance of 15 to 25 cm, propulsion speed of 1.5 to 3.5 mL / h, drum speed of 150 to 200 r / min, temperature of 30 to 50°C, relative humidity of 35 to 50 RH%, and spinning time of 7 to 9 hours.

[0016] Furthermore, in the spray-doping method for preparing the metal-organic framework / nanofiber composite membrane, the organic solvent is isopropyl alcohol. The material-liquid ratio is 500 mg of metal-organic framework material: isopropyl alcohol = 10-15 mL. When the dispersion is loaded into a pneumatic spray gun for spraying, the speed of the drum carrying the nanofiber membrane is set to 170-190 rpm. The spray is then repeated at a vertical distance of 5-6 cm from the membrane surface and within a lateral range of 10-15 cm to ensure that the metal-organic framework material is evenly loaded on the surface of the nanofiber membrane.

[0017] Furthermore, the preparation method of the metal-organic framework material includes the following steps: dissolving copper salt or zinc salt in deionized water, dissolving organic ligand in anhydrous ethanol, mixing the two solutions, stirring evenly and then transferring them to a polytetrafluoroethylene-lined reactor, hydrothermally reacting at 50-80°C for 10-15 hours, cooling to room temperature after the reaction, washing with N,N-dimethylformamide and anhydrous ethanol, centrifuging, and drying to obtain the metal-organic framework material.

[0018] Furthermore, the copper salt includes copper chloride, copper nitrate or copper acetate; the zinc salt includes zinc nitrate, zinc chloride or zinc carbonate.

[0019] Furthermore, the organic ligand is trimesic acid.

[0020] The present invention provides a C5F 10 Application of adsorption material for decomposition components of O mixed gas, said adsorption material is used to adsorb C5F 10 O mixed gas decomposition components.

[0021] Furthermore, the C5F 10 The decomposition components of the O mixed gas include hexafluoropropylene (C3F6) and carbon tetrafluoride (CF4).

[0022] The beneficial effects of the present invention are:

[0023] The adsorption material provided by the present invention, through the synergistic combination of metal-organic framework materials and porous nanofiber membrane substrates, forms a composite membrane with a larger specific surface area and more metal active sites, which promotes the adsorption of gas molecules, thereby accelerating the electron exchange rate between HKUST-1 (Cu) as a sensitive material and gas molecules, and also facilitates the penetration and diffusion of gas molecules, thereby significantly improving the gas sensitivity and adsorption effect of the adsorption material. In simulated testing under an environment of 150kPa and 298k, the adsorption material provided by the present invention showed that the concentration of the carbon fluoride product CF4 decreased by 153.06ppm compared to the initial concentration within a 60-day experimental period, and the concentration of C3F6 was close to 0, which is consistent with the C5F 10 There is a demand for better adsorption effect of the decomposition components C3F6 and CF4 of O mixed gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 is a scanning electron microscope image of the HKUST-1(Cu) / PAN composite film prepared in Example 2 of the present invention.

[0026] Figure 2 3 and 4 (A) of the present invention and comparative example 1 (B) show the time-concentration curves of the adsorption of CF4 gas components by the adsorption materials.

[0027] Figure 3 3 and 4 (A) of the present invention and comparative example 1 (B) show the time-concentration curves of the adsorption of C3F6 gas components by the adsorption materials. DETAILED DESCRIPTION

[0028] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0029] In a first aspect of the embodiment of the present invention, a C5F 10 O mixed gas decomposition component adsorption material, the adsorption material is prepared by uniformly dispersing the metal organic framework material on the nanofiber membrane obtained by electrospinning technology through spray doping method, and is used for adsorbing C5F10 Metal-organic framework / nanofiber composite membranes for decomposition of O mixed gases.

[0030] The adsorption material provided by the present invention is prepared by electrospinning technology to form nanofiber membrane, which is easy to process. Then, the metal organic framework material and the nanofiber membrane porous substrate are coordinated with each other by spray doping method to optimize C5F 10 O mixed gas adsorption materials, the resulting composite membrane has a larger specific surface area and more metal active sites. The metal-organic framework (MOF) material has a porous structure, exhibiting excellent adsorption properties. The interweaving of the MOF with the porous substrate creates a high specific surface area and large porosity, promoting the adsorption of gas molecules and facilitating their permeation and diffusion, thereby significantly improving the gas sensitivity and adsorption performance of the adsorbent material. Furthermore, combining the MOF material with the easily processable nanofiber membrane creates a specific structure that is easily integrated and exhibits excellent processing potential and mechanical properties.

[0031] In some feasible embodiments, further, 2.3 to 2.8 mg of the metal-organic framework material is sprayed on each square centimeter of the nanofiber membrane.

[0032] When the amount of MOF material used is too low, it is not evenly distributed on the nanofiber membrane substrate and the inter-fiber pores are incompletely filled. When the amount of MOF material is too high, it is wasted. Therefore, the present invention sprays 2.3 to 2.8 mg of MOF material per square centimeter of nanofiber membrane, ensuring a uniform distribution of the MOF material across the nanofiber membrane substrate and filling over 90% of the inter-fiber pores.

[0033] In some feasible embodiments, further, the metal-organic framework material includes HKUST-1(Cu) or HKUST-1(Zn).

[0034] The metal-organic framework material HKUST-1(Cu) has a porous structure with good adsorption properties. It is interwoven with the porous substrate of the nanofiber membrane, which has a high specific surface area and large porosity. This not only provides more contact sites for HKUST-1(Cu), promoting the adsorption of gas molecules, thereby accelerating the electron exchange rate between HKUST-1(Cu) as a sensitive material and gas molecules, but also facilitates the penetration and diffusion of gas molecules, thereby significantly improving the gas sensitivity and adsorption effect of the adsorbent material. Through simulation testing, the adsorbent material prepared with HKUST-1(Cu) under an environment of 150kPa and 298k, within a 60-day experimental period, the carbon fluorine product CF4 eventually decreased by 153.06ppm compared to the initial concentration, and the concentration of C3F6 was close to 0, which is consistent with the C5F 10There is a demand for better adsorption effect of the decomposition components C3F6 and CF4 of the O mixed gas. Therefore, the metal organic framework material is preferably HKUST-1 (Cu).

[0035] In some feasible embodiments, further, the nanofiber membrane includes a polyacrylonitrile nanofiber membrane, a polylactic acid nanofiber membrane, a polyvinyl alcohol nanofiber membrane, a polyimide nanofiber membrane or a polymethyl methacrylate nanofiber membrane.

[0036] Polyacrylonitrile nanofiber membranes have good weather resistance and sunlight resistance, can still maintain high strength after being placed outdoors for a long time, and are resistant to chemical reagents, especially inorganic acids and general organic reagents. Polylactic acid nanofiber membranes have excellent biodegradability and biocompatibility, and their high specific surface area and high porosity give them good filtration and separation properties, and can be used in adsorption fields such as water treatment and air purification. Although polymethyl methacrylate nanofiber membranes and polyvinyl alcohol nanofiber membranes have extremely large specific surface area and excellent filtration performance, their preparation conditions are difficult and their performance may need to be further optimized to meet the needs in specific application environments. Polyimide nanofiber membranes have higher porosity and excellent electrolyte wettability, but high porosity may cause mechanical properties to decline, which puts certain pressure on practical applications. Therefore, the nanofiber membranes of the present invention are preferably polyacrylonitrile nanofiber membranes and polylactic acid nanofiber membranes.

[0037] In a second aspect of the embodiment of the present invention, a C5F 10 The preparation method of the adsorption material of the decomposition component of the O mixed gas comprises the following steps:

[0038] Preparation of nanofiber membranes by electrospinning: A high molecular weight polymer is dissolved in an organic solvent, and the mixture is stirred continuously for 4 to 5 hours in a closed water bath at a temperature of 50 to 80°C to obtain an electrospinning precursor solution with a mass percent concentration of 5 to 15%. The nanofiber membranes are prepared by electrospinning.

[0039] Preparation of metal organic framework / nanofiber composite membrane by spray doping method: the metal organic framework material is mixed with the organic solvent, stirred at room temperature for 0.5 to 1 hour, and then ultrasonically dispersed in an ice bath for 2 to 3 hours to obtain a dispersion; the dispersion is loaded into a pneumatic spray gun for spraying, so that the dispersion is evenly sprayed back and forth on the surface of the nanofiber membrane. After spraying, it is placed in an oven at 80 to 85°C for drying for 12 to 14 hours to obtain a metal organic framework / nanofiber composite membrane.

[0040] Electrospinning utilizes the interaction of electrostatic force and surface tension to pull droplets or solutions into fibers under a strong electric field. Through solvent evaporation and solidification, the fibers retain their shape and structure without damaging the original structure. The nanofiber membranes produced using electrospinning technology offer advantages such as a wide range of fiber diameter control and low cost.

[0041] As an electrospinning precursor solution, when the concentration of the polymer is too low, the spun fibers may be thin and easy to break, with poor strength and toughness, and cannot meet the needs of practical applications. Moreover, during the spinning process, the low-concentration solution may form a bead-like structure rather than a continuous fibrous structure due to excessive surface tension. When the concentration of the polymer is too high, its viscosity is too high, resulting in poor solution flow during the spinning process and easy clogging of the nozzle. Due to the high viscosity of the solution, the spinning speed may be slow, and problems such as broken fibers may occur, resulting in reduced spinning efficiency. The present invention preferably uses a polymer solution with a mass percentage concentration of 5 to 15% as the electrospinning precursor solution. Within this concentration range, the polymer solution has a high viscosity and appropriate conductivity, which is conducive to forming a stable spinning jet, thereby ensuring the continuity and stability of the spinning process. And at an appropriate concentration, the spinning speed is relatively fast, and problems such as nozzle clogging are not likely to occur, thereby improving the spinning efficiency.

[0042] The present invention uses a spray-doping method to prepare a metal-organic framework / nanofiber composite membrane. This method is simple to prepare and allows for precise control of the amount of metal-organic framework material used. Through spraying, the metal-organic framework material is evenly distributed on the surface of the nanofiber membrane substrate, ensuring uniformity and consistency of the material.

[0043] In the present invention, the sprayed product is removed from the drum and placed in an oven at 80-85° C. for drying for 12-14 hours, which not only removes excess solvent but also activates the pores of the HKUST-1 (Cu) particles.

[0044] In some feasible embodiments, further, in the step of preparing the nanofiber membrane using the electrospinning technology: the polymer includes polyacrylonitrile (PAN), polylactic acid (PLA), polyvinyl alcohol, polyimide or polymethyl methacrylate. The organic solvent is selected from N,N-dimethylformamide (DMF) and chloroform. The conditions of the electrospinning technology are: voltage of 15-25 kV, receiving distance of 15-25 cm, propulsion speed of 1.5-3.5 mL / h, drum speed of 150-200 r / min, temperature of 30-50°C, relative humidity of 35-50 RH%, and spinning time of 7-9 hours.

[0045] DMF has good solubility for various organic and inorganic compounds and is a non-proton polar solvent. It can be mixed arbitrarily with water and most organic solvents and is particularly suitable for chemical reactions and processes that require high solubility. Even if DMF is heated to boiling point in the absence of acid, alkali or water, it is relatively stable and shows good chemical stability. Therefore, the preferred organic solvent of the present invention is DMF. The electrospinning conditions proposed by the present invention can not only ensure the stability of the spinning process and the high quality of the fiber, but also improve the spinning efficiency.

[0046] In some feasible embodiments, further, in the spray-doping method for preparing the metal-organic framework / nanofiber composite membrane, the organic solvent is isopropyl alcohol. According to the material-liquid ratio, the metal-organic framework material: isopropyl alcohol = 500 mg: 10-15 mL. When the dispersion is loaded into the pneumatic spray gun for spraying, the speed of the drum carrying the nanofiber membrane is set to 170-190 rpm, and the spray is reciprocated at a vertical distance of 5-6 cm from the membrane surface and a horizontal range of 10-15 cm to ensure that the metal-organic framework material is evenly loaded on the surface of the nanofiber membrane.

[0047] Too little isopropyl alcohol can lead to reduced reaction efficiency; when the amount of isopropyl alcohol is too high, it will compete with the metal-organic framework for adsorption. Therefore, the present invention preferably uses a material-liquid ratio of 500 mg of metal-organic framework material to isopropyl alcohol to 10-15 mL. The spraying conditions proposed in the present invention can ensure that the coating has a uniform thickness and a smooth surface, thereby improving the overall quality of the coating, increasing the adhesion of the coating, and preventing the coating from falling off or cracking.

[0048] In some feasible embodiments, further, the method for preparing the metal-organic framework material includes the following steps: dissolving a copper salt or a zinc salt in deionized water, dissolving an organic ligand in anhydrous ethanol, mixing the two solutions, stirring evenly, and then transferring them to a polytetrafluoroethylene-lined reactor, hydrothermally reacting at 50-80°C for 10-15 hours, and after the reaction is completed, cooling to room temperature, washing with N,N-dimethylformamide and anhydrous ethanol, centrifuging, and drying to obtain a metal-organic framework material.

[0049] In some feasible embodiments, further, the copper salt includes copper chloride, copper nitrate or copper acetate; the zinc salt includes zinc nitrate, zinc chloride or zinc carbonate. The organic ligand is trimesic acid.

[0050] The advantages of the hydrothermal method include: it is typically performed at medium to low temperatures, resulting in relatively low energy consumption, which helps reduce production costs; the reaction is carried out in the liquid phase, resulting in a relatively fast reaction rate; the reaction conditions are easily controlled, resulting in highly efficient products; and the process flow is relatively simple, requiring no complex equipment or steps. Therefore, the hydrothermal method is preferred for preparing HKUST-1(Cu) or HKUST-1(Zn).

[0051] In a third aspect of the embodiment of the present invention, a C5F 10 Application of adsorption material for decomposition components of O mixed gas, said adsorption material is used to adsorb C5F 10 O mixed gas decomposition components.

[0052] In some feasible embodiments, further, the C5F 10 The decomposition components of the O mixed gas include hexafluoropropylene (C3F6) and carbon tetrafluoride (CF4).

[0053] The adsorption material prepared by the present invention, the metal organic framework material HKUST-1 (Cu) has a porous structure and good adsorption performance. It is interwoven with the porous substrate of the nanofiber membrane to have a high specific surface area and large porosity, which promotes the adsorption of gas molecules and also helps the penetration and diffusion of gas molecules, thereby significantly improving the gas sensitivity and adsorption effect of the adsorption material. The HKUST-1 (Cu) / PAN composite membrane prepared by the present invention has a strong adsorption capacity for C3F6 and CF4, which can be used as a C5F 10 Through simulation testing, the adsorption material prepared with HKUST-1(Cu) at 150kPa and 298K environment, within a 60-day experimental period, the concentration of fluorocarbon product CF4 finally decreased by 153.06ppm compared with the initial concentration, and the concentration of C3F6 was close to 0, which is consistent with the decomposition of C5F 10 There is a demand for better adsorption effect of the decomposition components C3F6 and CF4 of O mixed gas.

[0054] Example 1

[0055] (1) Effect of polymers on the preparation of nanofiber membranes

[0056] Weigh 9g of DMF solvent into a conical flask, add a magnetic stir bar, and stir in a 60°C waterbath. Then weigh 1g of the polymer powder listed in Table 1 and slowly add it to the stirring conical flask. Close the flask tightly to prevent moisture or other impurities from entering the conical flask. Set the water bath temperature to 60°C and stir continuously for 4 hours until the solution is clear and transparent, obtaining an electrospinning precursor solution with a mass percentage concentration of 10%. Draw 10g of the prepared electrospinning precursor solution into a 20mL syringe. Secure the syringe to the spinning machine syringe pump, install a 20G needle, and proceed with electrospinning. The electrospinning conditions were: a voltage of 15 kV, a receiving distance of 20 cm between the needle and the drum, a propulsion rate of 2.0 mL / h for the electrospinning precursor solution, a drum rotation speed of 160 rpm, a spinning environment temperature of 35°C, a relative humidity of 40%, a reciprocating platform speed of 900 mm / min, tinfoil as the receiving substrate, and a spinning time of 7.5 hours to produce a nanofiber membrane. The porosity of the resulting nanofiber membrane was tested, and the results are shown in Table 1.

[0057] Table 1

[0058]

[0059]

[0060] The porosity of the nanofiber membrane determines the membrane's permeability and filtration efficiency. As shown in Table 1, nanofiber membranes prepared from the polymers PAN and PLA have higher porosity. Therefore, polyacrylonitrile (PAN) and polylactic acid (PLA) are preferred polymers for the present invention.

[0061] (2) Effect of electrospinning precursor solution concentration on the preparation of nanofiber membranes

[0062] Weigh DMF solvent into a conical flask, add a magnetic stir bar, and stir in a 60°C waterbath. Then weigh PAN powder and slowly add it to the stirring conical flask. Tightly cap the flask to prevent moisture or other impurities from entering the conical flask. Set the water bath temperature to 60°C and stir continuously for 4 hours until the solution is clear and transparent. Electrospinning precursor solutions of different concentrations are obtained as shown in Table 2. 10g of electrospinning precursor solution of different concentrations is drawn into a 20mL syringe. The syringe is fixed to the spinning machine syringe pump and equipped with a 20G needle for electrospinning. The electrospinning conditions were: a voltage of 15 kV, a receiving distance of 20 cm between the needle and the drum, a propulsion rate of 2.0 mL / h for the electrospinning precursor solution, a drum rotation speed of 160 rpm, a spinning environment temperature of 35°C, a relative humidity of 40%, a reciprocating platform speed of 900 mm / min, tinfoil as the receiving substrate, and a spinning time of 7.5 h. Nanofiber membranes were obtained. The results are shown in Table 2.

[0063] Table 2

[0064] Electrospinning precursor solution concentration Viscosity of electrospinning precursor solution 2％ 1.644 Pa·s 5％ 2.576 Pa·s 10％ 3.795 Pa·s 15％ 4.862 Pa·s 20％ 6.137 Pa·s

[0065] An electrospinning solution with too low a viscosity may prevent the solution from forming a proper jet, making spinning difficult and ultimately resulting in droplets. Excessively high viscosity, on the other hand, can cause significant jet instability, making spinning difficult and easily leading to very uneven nanofiber diameter and distribution. As shown in Table 2, a PAN concentration between 5% and 15% produces a good electrospinning precursor solution viscosity, while concentrations below 5% or above 15% produce poor results. Therefore, in the present invention, the preferred concentration of the electrospinning precursor solution is 5% to 15%, more preferably 10%.

[0066] Example 2

[0067] A C5F 10 The preparation method of HKUST-1(Cu) / PAN composite membrane, an adsorption material for decomposition components of O mixed gas, is as follows:

[0068] 1. Synthesis of HKUST-1(Cu) particles by hydrothermal method

[0069] 1.087 g of copper nitrate trihydrate (Cu(NO₃)₂·3H₂O) was dissolved in 15 mL of deionized water (DI). 0.525 g of trimesic acid (H₃-BTC) was dissolved in 15 mL of anhydrous ethanol (C₂H₂O). The two solutions were mixed, stirred, and then transferred to a Teflon-lined reactor for a hydrothermal reaction in a 60°C oven for 12 h. After the reaction, the Teflon liner was removed and the mixture was cooled to room temperature. The reaction mixture was transferred to a centrifuge tube and washed by centrifugation (9000 rpm, 5 min) using N,N-dimethylformamide (DMF) and anhydrous ethanol. This washing process was repeated three times. The precipitate was then dried in an 80°C oven for 12 h to obtain dark blue HKUST-1(Cu) particles.

[0070] 2. Preparation of nanofiber membranes using electrospinning technology

[0071] Use an electronic balance to weigh 9g of DMF solvent into a conical flask. Add a magnetic stir bar and stir in a 60°C water bath. Then weigh 1g of PAN powder and slowly add it to the stirring conical flask. Close the flask tightly to prevent moisture and other impurities from entering the conical flask. Set the water bath temperature to 60°C and stir continuously for 4 hours until the solution is clear and transparent, obtaining a PAN electrospinning precursor solution with a mass percentage concentration of 10%. Draw 10g of the prepared PAN electrospinning precursor solution into a 20mL syringe. Secure the syringe to the spinning machine syringe pump, install a 20G needle, and proceed with electrospinning. The electrospinning conditions were as follows: voltage of 15 kV, receiving distance between the needle and the drum of 20 cm, propulsion speed of the electrospinning precursor solution of 2.0 mL / h, drum speed of 160 r / min, spinning environment temperature of 35 ° C, relative humidity of 40 RH%, reciprocating platform speed of 900 mm / min, tin foil was used as the receiving substrate, spinning time of 7.5 h, and PAN nanofiber membrane was obtained.

[0072] 3. Preparation of metal organic framework / nanofiber composite membrane by spray doping method

[0073] 500 mg of HKUST-1(Cu) particles were added to a 20 mL sample vial containing 12 mL of isopropyl alcohol (IPA). After stirring at room temperature for 0.5 h using a magnetic stirrer, the dispersion was then ultrasonically dispersed in an ice bath at 750 W for 2 h, yielding a uniform dark blue dispersion. The dispersion was then applied to a pneumatic spray gun for spraying. The drum carrying the PAN nanofiber membrane was rotated at 180 rpm, and the spray was applied reciprocally within a 10 cm horizontal range and 5 cm vertically from the membrane surface, ensuring a uniform loading of the HKUST-1(Cu) particles on the PAN nanofiber membrane surface. After spraying, the product was removed from the drum and dried in an 80°C oven for 12 h to remove excess solvent and activate the pores of the HKUST-1(Cu) particles. This resulted in a metal-organic framework / nanofiber composite membrane, labeled HKUST-1(Cu) / PAN composite membrane. 2.5 mg of HKUST-1(Cu) was sprayed per square centimeter of the PAN nanofiber membrane.

[0074] Figure 1 is a scanning electron microscope image of the HKUST-1(Cu) / PAN composite film prepared in this example. Figure 1 It can be seen that the fibers in the composite membrane are interlaced to form a polyacrylonitrile porous substrate. With the polyacrylonitrile porous substrate as a support, HKUST-1(Cu) grows uniformly and stably on the porous substrate.

[0075] Example 3

[0076] A C5F 10The preparation method of HKUST-1(Cu) / PLA composite membrane, an adsorption material for decomposition components of O mixed gas, is as follows:

[0077] 1. Synthesis of HKUST-1(Cu) particles by hydrothermal method

[0078] Same as Example 2

[0079] 2. Preparation of nanofiber membranes using electrospinning technology

[0080] Use an electronic balance to weigh 9g of DMF solvent into a conical flask, add a magnetic stir bar, and stir in a 60°C water bath. Weigh 2g of PLA powder and dissolve it in 9g of chloroform solution. Slowly add the dissolved PLA solution to the stirring DMF solvent and secure the flask tightly to prevent moisture and other impurities from entering the conical flask. Set the water bath temperature to 60°C and stir continuously for 4 hours until the solution becomes clear and transparent, resulting in a 10% mass percent concentration of PLA electrospinning precursor solution. Draw 10g of the PLA electrospinning precursor solution into a 20mL syringe. Secure the syringe to the syringe pump of the spinning machine, attach a 20G needle, and proceed with electrospinning. The electrospinning conditions were as follows: voltage of 20 kV, receiving distance between the needle and the drum of 25 cm, propulsion speed of the electrospinning precursor solution of 3.0 mL / h, drum speed of 200 r / min, spinning environment temperature of 50 ° C, relative humidity of 50 RH%, reciprocating platform speed of 1000 mm / min, tin foil was used as the receiving substrate, spinning time of 9 h, and PLA nanofiber membrane was obtained.

[0081] 3. Preparation of metal organic framework / nanofiber composite membrane by spray doping method

[0082] 500 mg of HKUST-1(Cu) particles were added to a 20 mL sample vial containing 12 mL of isopropyl alcohol (IPA). After stirring at room temperature for 0.5 h using a magnetic stirrer, the dispersion was then ultrasonically dispersed in an ice bath at 750 W for 2 h, yielding a uniform dark blue dispersion. The dispersion was then applied to a pneumatic spray gun for spray coating. The drum carrying the PLA nanofiber membrane was rotated at 180 rpm, and the spray was applied reciprocally within a 10 cm horizontal range and 5 cm vertically from the membrane surface, ensuring a uniform loading of the HKUST-1(Cu) particles on the PLA nanofiber membrane surface. After spraying, the product was removed from the drum and dried in an 80°C oven for 12 h to remove excess solvent and activate the HKUST-1(Cu) particle pores. This resulted in a metal-organic framework / nanofiber composite membrane, labeled HKUST-1(Cu) / PLA composite membrane. 2.5 mg of HKUST-1(Cu) was sprayed per square centimeter of the PLA nanofiber membrane.

[0083] Example 4

[0084] A C5F 10 The preparation method of HKUST-1(Zn) / PAN composite membrane, an adsorption material for decomposition components of O mixed gas, is as follows:

[0085] 1. Synthesis of HKUST-1(Zn) particles by hydrothermal method

[0086] 1.488 g of zinc nitrate hexahydrate (Zn(NO₃)₂·6H₂O) was dissolved in 15 mL of deionized water (DI). 0.525 g of trimesic acid (H₃-BTC) was dissolved in 15 mL of anhydrous ethanol (C₂H₂O). The two solutions were mixed, stirred, and then transferred to a Teflon-lined reactor for a hydrothermal reaction in a 60°C oven for 15 h. After the reaction, the Teflon liner was removed and the mixture was cooled to room temperature. The reaction mixture was transferred to a centrifuge tube and washed by centrifugation (9000 rpm, 5 min) using N,N-dimethylformamide (DMF) and anhydrous ethanol. This washing process was repeated three times. The precipitate was then dried in a 100°C oven for 10 h to obtain light yellow HKUST-1(Zn) particles.

[0087] 2. Preparation of nanofiber membranes using electrospinning technology

[0088] The same as Example 2, except that the electrospinning conditions were changed, to obtain a PAN nanofiber membrane.

[0089] The conditions for electrospinning were as follows: voltage of 15 kV, receiving distance between needle and roller of 20 cm, propulsion speed of electrospinning precursor solution of 2.0 mL / h, roller speed of 150 r / min, spinning environment temperature of 35 °C, relative humidity of 40 RH%, reciprocating platform speed of 800 mm / min, tin foil as receiving substrate, and spinning time of 9 h.

[0090] 3. Preparation of metal organic framework / nanofiber composite membrane by spray doping method

[0091] 500 mg of HKUST-1(Zn) particles were added to a 20 mL sample vial containing 12 mL of isopropyl alcohol (IPA). After stirring at room temperature for 0.5 h using a magnetic stirrer, the dispersion was then ultrasonically dispersed in an ice bath at 750 W for 2 h, yielding a uniform dark blue dispersion. The dispersion was then applied to a pneumatic spray gun for spraying. The drum carrying the PAN nanofiber membrane was rotated at 180 rpm, and the spray was applied reciprocally within a 10 cm horizontal range and 5 cm vertically from the membrane surface, ensuring a uniform loading of the HKUST-1(Zn) particles on the PAN nanofiber membrane surface. After spraying, the product was removed from the drum and dried in an 80°C oven for 12 h to remove excess solvent and activate the pores of the HKUST-1(Zn) particles. This resulted in a metal-organic framework / nanofiber composite membrane, labeled HKUST-1(Zn) / PAN composite membrane. 2.5 mg of HKUST-1(Zn) was sprayed per square centimeter of the PAN nanofiber membrane.

[0092] Example 5

[0093] A C5F 10 Application of adsorption materials for decomposition components of mixed gases (I) Different adsorption materials for C5F 10 Effect of O2 mixture gas decomposition components on adsorption performance

[0094] Here’s how:

[0095] The adsorption materials prepared in Example 2, Example 3 and Example 4 were placed in a stainless steel adsorption chamber at room temperature. The adsorption chamber had a volume of 1.7 L and was filled with the experimental gas (the experimental gas composition was: 15% C5F 10 O / 85% CO2, the mass is negligible relative to the main gas, where the initial concentration of C3F6 is 545μL / L and the initial concentration of CF4 is 5μL / L). The experimental gas is filled to 150kPa and the adsorption experiment is carried out at room temperature. Gas collection and component detection are performed on the 5th, 10th, 15th, 20th and 60th days respectively. The results are as follows Figure 2 and Figure 3 .

[0096] The adsorption material of Comparative Example 1 is 5A molecular sieve (item number M103775) currently available on the market.

[0097] Figure 2 The time-concentration curves of the adsorbent materials of Examples 2, 3, 4 and Comparative Example 1 for CF4 gas components are shown in FIG. Figure 2 It can be seen that for C5F 10The decomposition component of the mixed gas, carbon tetrafluoride (CF4), was observed in the adsorbent prepared in Example 2 over a 60-day experimental period, with the CF4 concentration continuously decreasing, ultimately reaching a decrease of 153.06 ppm compared to the initial concentration. The CF4 concentration in the adsorbent prepared in Example 3 ultimately decreased by 103.75 ppm compared to the initial concentration. The CF4 concentration in the adsorbent prepared in Example 4 ultimately decreased by 127.21 ppm compared to the initial concentration.

[0098] Figure 3 The time-concentration curves of the adsorbent materials of Examples 2, 3, 4 and Comparative Example 1 for C3F6 gas components are shown in FIG. Figure 3 It can be seen that for C5F 10 The adsorbent prepared in Example 2, which decomposes hexafluoropropylene (C3F6) into a component of the mixed gas, achieved a C3F6 concentration close to zero on the 20th day within a 60-day experimental period. The adsorbents prepared in Examples 3 and 4 were also able to adsorb C3F6 within 60 days, with the C3F6 concentration close to zero, though the time required was longer than that in Example 2.

[0099] In summary, the adsorption effect of the adsorption material HKUST-1(Cu) / PAN composite membrane prepared in Example 2 is Figure 2 It can be seen that within 60 days, the concentration of CF4 continued to decrease, and finally decreased by 153.06ppm compared with the initial concentration. Figure 3 It can be seen that the concentration of C3F6 dropped to below 25% on the 5th day and was close to zero on the 20th day. Combined with the molecular dynamics simulation results, since HKUST-1(Cu) / PAN has a strong interaction with the C=C double bond in C3F6 and the production of C3F6 itself is relatively small, its concentration dropped rapidly. The adsorption material of Example 2 has a significant adsorption effect on both C3F6 and CF4 at room temperature, and can meet the requirements of adsorbing C3F6 and CF4, and can be applied to C5F 10 Adsorption materials for characteristic decomposition components of O mixed gases.

[0100] (II) Effect of the loading amount of metal organic framework materials on C5F 10 Effect of O2 mixture gas decomposition components on adsorption performance

[0101] Here’s how:

[0102] 1. Synthesis of HKUST-1(Cu) particles by hydrothermal method

[0103] The method is the same as Example 2.

[0104] 2. Preparation of nanofiber membranes using electrospinning technology

[0105] The method is the same as Example 2.

[0106] 3. Preparation of metal organic framework / nanofiber composite membrane by spray doping method

[0107] The method is the same as that of Example 2. The difference is that the spraying amount of the metal organic framework material is controlled, that is, the metal organic framework material shown in Table 3 is sprayed per square centimeter of the nanofiber membrane to obtain metal organic framework / nanofiber composite membranes with different spraying amounts.

[0108] 4. Adsorption effect

[0109] The prepared metal organic framework / nanofiber composite membranes with different spraying amounts were placed in a stainless steel adsorption chamber at room temperature. The adsorption chamber volume was 1.7 L, and the adsorption chamber was filled with experimental gas (the experimental gas composition was: 15% C5F 10 The adsorption experiment was conducted at room temperature with an initial pressure of 150 kPa (1000 psi) and a pressure of 85% CO (with a negligible mass relative to the main gas). The initial concentrations of C3F6 and CF4 were 545 μL / L and 5 μL / L, respectively. CF4 gas was collected and its components were analyzed on the 60th day. The results are shown in Table 3.

[0110] Table 3

[0111] Metal-organic framework material content <![CDATA[The CF4 gas component decreased after 60 days compared to the initial concentration]]> <![CDATA[1mg / cm 2 ]]> 77.49ppm <![CDATA[2mg / cm 2 ]]> 121.47ppm <![CDATA[2.3mg / cm 2 ]]> 138.96ppm <![CDATA[2.5mg / cm 2 ]]> 153.06ppm <![CDATA[2.8mg / cm 2 ]]> 155.72ppm <![CDATA[3mg / cm 2 ]]> 152.86ppm <![CDATA[4mg / cm 2 ]]> 136.02ppm

[0112] By spraying different contents of metal organic framework materials, CF4 gas component adsorption experiments were conducted. As shown in Table 3, when the metal organic framework content was low, the CF4 gas adsorption amount was significantly reduced to 2.5 mg / cm 2 When the adsorption capacity is basically saturated, when the metal organic framework content is increased, it may cause waste, and even worse, it may cause fiber pore clogging and reduce the adsorption capacity. In the present invention, it is preferred to spray 2.3-2.8mg of metal organic framework material per square centimeter of nanofiber membrane, and more preferably 2.5mg.

[0113] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed. The above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application. The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application. These improvements and variations should also be regarded as the scope of protection of the present application.

Claims

1. A C5F 10 The application of the adsorption material for decomposition components of O mixed gas is characterized by: The adsorption material is prepared by uniformly dispersing the metal organic framework material on the nanofiber membrane obtained by electrospinning technology through spray doping method to adsorb C5F. 10 O mixed gas decomposition components of the metal organic framework / nanofiber composite membrane; wherein 2.3 to 2.8 mg of metal organic framework material is sprayed on each square centimeter of the nanofiber membrane; the metal organic framework material comprises HKUST-1 (Cu) or HKUST-1 (Zn); the nanofiber membrane comprises a polyacrylonitrile nanofiber membrane or a polylactic acid nanofiber membrane; The adsorption material is used to adsorb C5F 10 O mixed gas decomposition components, the C5F 10 The decomposition components of the O mixed gas include hexafluoropropylene and carbon tetrafluoride.

2. The use according to claim 1, characterized in that The preparation method of the adsorption material comprises the following steps: Preparation of nanofiber membranes by electrospinning: A polymer is dissolved in an organic solvent, and the solution is stirred continuously for 4-5 hours in a closed water bath at a temperature of 50-80°C to obtain an electrospinning precursor solution having a mass percent concentration of 5-15%, wherein the polymer comprises polyacrylonitrile or polylactic acid; and the nanofiber membranes are prepared by electrospinning. Preparation of metal organic framework / nanofiber composite membrane by spray doping method: the metal organic framework material is mixed with the organic solvent, stirred at room temperature for 0.5 to 1 hour, and then ultrasonically dispersed in an ice bath for 2 to 3 hours to obtain a dispersion; the dispersion is loaded into a pneumatic spray gun for spraying, so that the dispersion is evenly sprayed back and forth on the surface of the nanofiber membrane. After spraying, it is placed in an oven at 80 to 85°C for drying for 12 to 14 hours to obtain a metal organic framework / nanofiber composite membrane.

3. The use according to claim 2, characterized in that In the step of preparing nanofiber membrane using the electrospinning technology: the organic solvent is selected from N,N-dimethylformamide and chloroform; the conditions of the electrospinning technology are: voltage of 15-25 kV, receiving distance of 15-25 cm, propulsion speed of 1.5-3.5 mL / h, drum speed of 150-200 r / min, temperature of 30-50°C, relative humidity of 35-50 RH%, and spinning time of 7-9 h.

4. The use according to claim 2, characterized in that In the step of preparing the metal-organic framework / nanofiber composite membrane by the spray doping method, the organic solvent is isopropyl alcohol; according to the material-liquid ratio, the metal-organic framework material: isopropyl alcohol = 500 mg: 10-15 mL; when the dispersion is loaded into the pneumatic spray gun for spraying, the rotation speed of the drum carrying the nanofiber membrane is set to 170-190 r / min, and the spraying is repeated at a vertical distance of 5-6 cm from the membrane surface and a horizontal range of 10-15 cm, so that the metal-organic framework material is evenly loaded on the surface of the nanofiber membrane.

5. The use according to claim 2, characterized in that The metal-organic framework material preparation method includes the following steps: dissolving a copper salt or a zinc salt in deionized water, dissolving an organic ligand in anhydrous ethanol, mixing the two solutions, stirring them evenly, and then transferring them to a polytetrafluoroethylene-lined reactor, performing a hydrothermal reaction at 50-80° C. for 10-15 hours, cooling to room temperature after the reaction, washing with N,N-dimethylformamide and anhydrous ethanol, centrifuging, and drying to obtain the metal-organic framework material.

6. The use according to claim 5, characterized in that The copper salt includes copper chloride, copper nitrate or copper acetate; the zinc salt includes zinc nitrate, zinc chloride or zinc carbonate; and the organic ligand is trimesic acid.

Images