A carbon molecular sieve with adjustable pore size and its preparation method and application

Abstract

The present invention discloses a carbon molecular sieve with adjustable pore size, its preparation method and application. The thermosetting polymer and / or pre-oxidized thermosetting polymer is carbonized and pyrolyzed under a specific atmosphere, and the obtained carbon molecular sieve has a main micropore diameter adjustable within 3 to 10 Å, which is consistent with the raw material sp 2 / sp 3 There is a correlation between the carbonization temperature and the carbonization value. Under nitrogen and / or argon atmospheres, the correlation is n = 17.17-2.4S-0.0096T; under carbon dioxide atmosphere, the correlation is n = 0.55-3.5S + 0.01T. This correlation can be used to guide the preparation and pore size control of this series of carbon molecular sieves. The prepared carbon molecular sieves can be used for the separation and purification of alkenes, alkanes, and specialty gases.

Description

Technical Field

[0001] The present invention belongs to the technical field of carbon molecular sieves, and in particular relates to a carbon molecular sieve with adjustable pore size, a preparation method and an application thereof. Background Art

[0002] Carbon molecular sieves (CMS) are primarily composed of relatively concentrated micropores and a small number of macropores. They possess a highly developed pore structure and exceptional surface activity. The performance of CMS in separation and catalysis applications depends primarily on their pore structure and surface properties, with pore size distribution typically ranging from 0.3 to 1.0 nm. By manipulating the pore size of CMS, they can be tailored to suit the desired separation system.

[0003] Currently, the main methods for adjusting the pore size of carbon molecular sieves include physical activation, chemical activation, templates, and chemical vapor deposition. Physical activation involves high-temperature treatment or gas activation to control pore size. Common activators include water vapor and carbon dioxide. This method is simple to operate, but the pore size distribution is wide, making precise control difficult. Chemical activation involves reacting chemical reagents such as KOH and H₃PO₄ with the carbon material, adjusting the pore size by controlling the reaction conditions. This method can achieve a narrow pore size distribution, but may introduce impurities, affecting material purity. Templates are an emerging pore adjustment technology that uses nanoparticles or block copolymers as templates to precisely control pore size and distribution. This method can produce carbon molecular sieves with regular pore structures, but the process is complex and costly. Currently, chemical vapor deposition (CVD) is the most widely used method for adjusting the pore size of carbon molecular sieves in industry. CVD modifies the pores by decomposing a gaseous precursor at high temperature, depositing it on a substrate, and carbonizing it, thereby producing carbon molecular sieves with narrow pores. For example, patent application (CN107324307A) uses high-concentration methane deposition for initial pore adjustment, followed by secondary pore adjustment using low-concentration methane deposition, thereby modifying and reducing the pore size. Patent application (CN114797761A) employs benzene vapor deposition combined with metal modification to adjust the pore size and structure of a carbon molecular sieve, making it suitable for methane and nitrogen separation. Although these carbon molecular sieves achieve pore size control within the microporous range, they still have a wide pore size distribution and a limited range of pore size control, limiting their application to the separation of one or a few gases.

[0004] Therefore, there is a need for a method that is simple, safe, green, and can achieve a narrow pore size distribution of carbon molecular sieves in the range of 3 Å to 10 Å, so as to be suitable for the separation of various gas systems. Summary of the Invention

[0005] In order to solve the shortcomings and deficiencies of the prior art, the primary purpose of the present invention is to provide a thermosetting polymer as a raw material, using high temperature control and gas activation and adjustment of the precursor sp 2 / sp 3 The invention discloses a method for preparing carbon molecular sieve with adjustable pore size by combining the method of the ratio.

[0006] Another object of the present invention is to provide a carbon molecular sieve with adjustable pore size obtained by the above method.

[0007] Another object of the present invention is to provide an application of the above-mentioned carbon molecular sieve with adjustable pore size.

[0008] Another object of the present invention is to provide a method for gas separation using the above-mentioned carbon molecular sieve with adjustable pore size.

[0009] The purpose of the present invention is achieved through the following technical solutions:

[0010] A method for regulating the pore size of a carbon molecular sieve comprises the following steps:

[0011] (1) Using thermosetting polymer as raw material, determine the parameter S0 of the thermosetting polymer and the target pore size n0 of the carbon molecular sieve;

[0012] Where S0 is sp 2 With sp 3 The ratio of

[0013] (2) If n0 is in the range of 3 to 5 Å, substitute S0 and n0 into formula (1) to calculate the carbonization temperature T i , the thermosetting polymer is placed in a nitrogen and / or argon atmosphere and the carbonization temperature T i Carbonization treatment was carried out under the condition of i carbon molecular sieves;

[0014] n=17.17-2.4S-0.0096T (1)

[0015] If n0 is in the range of 5 to 10 Å, substitute S0 and n0 into formula (2) to calculate the carbonization temperature T i , the thermosetting polymer is placed in a carbon dioxide atmosphere and the carbonization temperature T i Carbonization treatment was carried out under the condition of i carbon molecular sieves;

[0016] n=0.55-3.5S+0.01T (2)

[0017] In formulas (1) and (2), n is the main pore size of the carbon molecular sieve, in angstroms; S is the structural order of the thermosetting polymer, expressed in sp 2 With sp 3The ratio of is expressed as; T is the carbonization temperature, in degrees Celsius;

[0018] (3) If △n=|n i -n0|≤0.3Å, then the carbon molecular sieve with the target pore size is obtained; otherwise, the carbonization temperature T is adjusted. i , the thermosetting polymer is carbonized in the corresponding gas atmosphere and the adjusted carbonization temperature until △n=|n i -n0|≤0.3Å, to obtain carbon molecular sieve with target pore size.

[0019] In the above technical solution, when n0 is 5 Å, the carbonization temperature T calculated by formula (1) or formula (2) is i Although different, carbon molecular sieves with the same target pore size can be obtained by carbonizing at these two carbonization temperatures in combination with their corresponding different gas atmospheres, as described in the implementation cases of Examples 10 and 11.

[0020] Preferably, the thermosetting polymer in step (1) is at least one of epoxy resin, phenolic resin, furfuryl alcohol resin, polyurethane and polyimide, and / or is at least one of pre-oxidized epoxy resin, pre-oxidized phenolic resin, pre-oxidized furfuryl alcohol resin, pre-oxidized polyurethane and pre-oxidized polyimide; more preferably, it is at least one of phenolic resin and pre-oxidized phenolic resin.

[0021] More preferably, the pre-oxidation treatment method is: carbonizing at least one thermosetting polymer selected from epoxy resin, phenolic resin, furfuryl alcohol resin, polyurethane and polyimide in an oxygen-containing atmosphere at 100-300° C. for 0-6 hours, wherein the carbonization time is not 0.

[0022] More preferably, the oxygen-containing atmosphere is air.

[0023] More preferably, the thermosetting polymer is carbonized in an air atmosphere at 100-300° C. for 3-6 hours, or in an air atmosphere at 100-250° C. for 3-6 hours.

[0024] More preferably, the programmed heating rate of the pre-oxidation treatment is 3-15°C / min; more preferably 5°C / min.

[0025] Preferably, the range of n0 in step (1) is 3 to 10 Å; more preferably 3 to 8 Å; and most preferably 4 to 6 Å.

[0026] Preferably, the parameter S0 in step (1) ranges from 0.8 to 1.6; more preferably, from 0.8 to 1.45; and most preferably, from 1.0 to 1.4.

[0027] Preferably, during the carbonization treatment in step (2), the gas flow rates of nitrogen and / or argon and carbon dioxide are all 10 to 1000 ml / min.

[0028] Preferably, the purity of the nitrogen and / or argon and carbon dioxide in step (2) is 95-99.999%.

[0029] Preferably, the temperature of the carbonization treatment in step (2) is 600-1600°C, and the time is 0.5-3 hours; more preferably, the temperature of the carbonization treatment is 780-1274°C, and the time is 0.5-3 hours; most preferably, the temperature of the carbonization treatment is 818-1100°C, and the time is 1-2 hours.

[0030] Preferably, the programmed heating rate of the carbonization treatment in step (2) is 3 to 15°C / min; more preferably 5°C / min.

[0031] Preferably, in step (3), the carbonization temperature T is adjusted i Refers to the carbonization temperature T i Adjust up and down 20 ~ 30 ℃; Specifically: if the atmosphere is nitrogen and / or argon, when the measured aperture n i When the pore size n0 is larger than the target pore size, the carbonization temperature is increased by 20 to 30°C. i When the pore size is smaller than the target pore size n0, the carbonization temperature is lowered by 20-30°C; if the atmosphere is carbon dioxide, when the measured pore size n i When the pore size is smaller than the target pore size n0, the carbonization temperature is increased by 20 to 30°C. i When the pore size is larger than the target pore size n0, the carbonization temperature is lowered by 20 to 30°C.

[0032] More preferably, in step (3), the carbonization temperature T is adjusted i Refers to the carbonization temperature T i Adjust up and down 25℃; specifically: if the atmosphere is nitrogen and / or argon, when the measured aperture n i When the pore size n0 is larger than the target pore size, the carbonization temperature is increased by 25℃. i When the pore size is smaller than the target pore size n0, the carbonization temperature is lowered by 25°C; if the atmosphere is carbon dioxide, when the measured pore size n i When the pore size is smaller than the target pore size n0, the carbonization temperature is increased by 25°C. i When the pore size is larger than the target pore size n0, the carbonization temperature is lowered by 25°C.

[0033] The present invention also provides a carbon molecular sieve with adjustable pore size obtained by the above-mentioned method for regulating the pore size of a carbon molecular sieve.

[0034] The present invention also provides application of the carbon molecular sieve with adjustable pore size in gas separation.

[0035] Preferably, the gas separation or purification system is one of an olefin-alkane mixed gas system and a fluorine-containing electronic specialty gas system.

[0036] More preferably, the olefin-alkane mixed gas system is one of C3H6 / C3H8 and C2H4 / C2H6.

[0037] More preferably, the fluorine-containing electronic specialty gas system is one of C3H8 / CH3F, NF3 / CF4, C2ClF5 / C2HF5, C2ClF5 / C3F8, and C3F6 / C3F8; most preferably, it is one of C3H8 / CH3F, NF3 / CF4, C2ClF5 / C3F8, and C3F6 / C3F8.

[0038] The present invention also provides a method for gas separation using the above-mentioned carbon molecular sieve with adjustable pore size, comprising the following steps:

[0039] (1) Determine the target gas system to be separated and the target pore size n0 required for the carbon molecular sieve;

[0040] (2) Obtaining a carbon molecular sieve with a target pore size according to the above-mentioned method for controlling the pore size of the carbon molecular sieve;

[0041] (3) Using carbon molecular sieves with target pore size for separation of target gas systems.

[0042] Preferably, the target gas system in step (1) is one of an olefin-alkane mixed gas system and a fluorine-containing electronic specialty gas system.

[0043] More preferably, the olefin-alkane mixed gas system is one of C3H6 / C3H8 and C2H4 / C2H6.

[0044] More preferably, the fluorine-containing electronic specialty gas system is one of C3H8 / CH3F, NF3 / CF4, C2ClF5 / C2HF5, C2ClF5 / C3F8, and C3F6 / C3F8; most preferably, it is one of C3H8 / CH3F, NF3 / CF4, C2ClF5 / C3F8, and C3F6 / C3F8.

[0045] Preferably, the method for separating the target gas system in step (3) is: at room temperature, the target gas system is passed through a fixed bed filled with a carbon molecular sieve of target pore size at a certain flow rate, thereby achieving gas adsorption separation.

[0046] More preferably, the ratio of the target gas system flow rate to the carbon molecular sieve is 1-10 ml / min: 200-700 mg.

[0047] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0048] It effectively solves the problems of unclear pore size control direction and imprecise pore size control scale in the preparation process of carbon molecular sieves, provides a precisely adjustable pore size control path within the pore size range of 3 Å to 10 Å, and can be effectively applied to corresponding gas separations. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is a flow chart of a method according to an embodiment of the present invention.

[0050] Figure 2 is the adsorption isotherm of Example 1.

[0051] Figure 3 This is the transmission curve of Example 1.

[0052] Figure 4 This is the adsorption isotherm of Example 2.

[0053] Figure 5 This is the transmission curve of Example 2.

[0054] Figure 6 This is the pore size distribution diagram of Example 3.

[0055] Figure 7 This is the adsorption isotherm of Example 3.

[0056] Figure 8 This is the transmission curve of Example 3.

[0057] Figure 9 This is the pore size distribution diagram of Example 4.

[0058] Figure 10 This is the adsorption isotherm of Example 4.

[0059] Figure 11 This is the transmission curve of Example 4.

[0060] Figure 12 This is the pore size distribution diagram of the carbon molecular sieve obtained in the first attempt in Example 5.

[0061] Figure 13 This is the adsorption isotherm of the carbon molecular sieve finally obtained in Example 5.

[0062] Figure 14 This is the transmission curve of Example 5.

[0063] Figure 15 This is the pore size distribution diagram of the carbon molecular sieve obtained in the first attempt in Example 6.

[0064] Figure 16 This is the pore size distribution diagram of the carbon molecular sieve finally obtained in Example 6.

[0065] Figure 17 This is the adsorption isotherm of Example 6.

[0066] Figure 18 This is the transmission curve of Example 6.

[0067] Figure 19 This is the adsorption isotherm of Example 7.

[0068] Figure 20 This is the transmission curve of Example 7.

[0069] Figure 21 This is the pore size distribution diagram of Example 8.

[0070] Figure 22 This is the adsorption isotherm of Example 8.

[0071] Figure 23 This is the transmission curve of Example 8.

[0072] Figure 24 This is the pore size distribution diagram of Examples 9 and 10.

[0073] Figure 25 This is the pore size distribution diagram of Examples 11 to 13. DETAILED DESCRIPTION

[0074] The present invention will be described in further detail below with reference to examples and drawings, but the embodiments of the present invention are not limited thereto.

[0075] In the examples of the present invention, if the specific conditions are not specified, the experiments were carried out according to conventional conditions or the conditions recommended by the manufacturer. All raw materials and reagents used without specifying the manufacturer are conventional products that can be purchased from the market.

[0076] A particular and important advantage of the present invention is that carbon molecular sieves with a primary pore size range of 3 Å to 10 Å can be obtained by preselecting preparation conditions according to a formula, and two preparation schemes with different carbon molecular sieve pore size variation trends are provided: an Ar / N2 atmosphere and a CO2 atmosphere. Among them, an N2 atmosphere is suitable for preparing carbon molecular sieves with a primary pore size of 3 Å to 5 Å, while a CO2 atmosphere is suitable for preparing carbon molecular sieves with a primary pore size of 5 Å to 10 Å.

[0077] Table 1 Experimental conditions of Examples 1 to 8

[0078]

[0079] Example 1

[0080] (1) The separation gas system was determined to be C2H4 / C2H6, and the target pore size n0 of the required carbon molecular sieve was 4.1Å.

[0081] (2) Phenolic resin was selected as the raw material and purchased from Borun New Material Technology Co., Ltd., item number 2123A.

[0082] The phenolic resin was heated to 200°C in air at a temperature of 5°C / min and kept pre-oxidized for 6 hours to obtain a pre-oxidized phenolic resin. The S0=sp 2 / sp 3 The value is 1.04.

[0083] (3) Since the target pore size n0 of carbon molecular sieve is 4.1Å, in the range of 3 to 5Å, substitute S0=1.04 and n0=4.1Å into formula (1) to calculate the carbonization temperature T i =1101℃;

[0084] Select nitrogen atmosphere, and heat the phenolic resin pre-oxidized in step (2) to 1101°C at 5°C / min and maintain for 1 hour under nitrogen atmosphere with a gas flow rate of 60 ml / min, and then cool naturally to room temperature to obtain a carbon molecular sieve. The adsorption isotherm of the carbon molecular sieve is as follows: Figure 2 As shown, according to Figure 2 The actual pore size n of the carbon molecular sieve is inferred from the isotherm curve i In the range of 4.1 to 4.2 Å, △n=|n i -n0|≤0.3 Å.

[0085] (4) The carbon molecular sieve obtained in step (3) was used for the separation of C2H4 / C2H6, and the adsorption isotherms of C2H4 and C2H6 at 298K were measured using a 3Flex three-station gas adsorption instrument from Micromeritics, USA. Figure 2 As shown. The results show that the carbon molecular sieve has an obvious screening effect on C2H4 / C2H6, with a selectivity of 12, proving that its pore size is between the kinetic diameters of C2H4 and C2H6. Under the conditions of 298K and 1bar, the adsorption capacity of C2H4 by the carbon molecular sieve is as high as 2.1mmol / g, proving that it has the ability to extract high-purity C2H4 from the C2 binary components. The carbon molecular sieve was further used for the dynamic separation of C2H4 / C2H6 mixed gas. The specific experimental process is: at room temperature, the C2H4 / C2H6 (volume ratio 1:1) mixed gas is passed through a fixed bed filled with adsorption material at a flow rate of 1ml / min, and the filler is 700mg of adsorbent. The effluent gas from the fixed bed is analyzed by GC-6600 gas chromatograph and hydrogen flame ionization detector (FID). The resulting permeation curve is shown as follows. Figure 3As shown in the figure, it can be seen that the non-adsorbed C2H6 flows out first, and C2H4 flows out after the adsorbent is saturated with adsorption. The separation time of C2H4 and C2H6 exceeds 30min / g, indicating that the carbon molecular sieve has excellent C2H4 / C2H6 separation performance.

[0086] Example 2

[0087] (1) The separation gas system was determined to be C3H6 / C3H8, and the target pore size n0 of the required carbon molecular sieve was 4.4Å.

[0088] (2) Phenolic resin was selected as the raw material and purchased from Henan Jinrun New Materials Co., Ltd., item number 2123F.

[0089] The phenolic resin was heated to 100°C in air at a temperature of 5°C / min and kept pre-oxidized for 3 hours to obtain a pre-oxidized phenolic resin. The S0=sp 2 / sp 3 The value is 1.28.

[0090] (3) Since the target pore size n0 of carbon molecular sieve is 4.4Å, in the range of 3 to 5Å, substitute S0=1.28 and n0=4.4Å into formula (1) to calculate the carbonization temperature T i =1010℃;

[0091] Select nitrogen atmosphere, and heat the phenolic resin pre-oxidized in step (2) to 1010°C at 5°C / min and keep it for 0.5 hours under nitrogen atmosphere with a gas flow rate of 60 ml / min, and then cool it naturally to room temperature to obtain a carbon molecular sieve. The adsorption isotherm of the carbon molecular sieve is as follows: Figure 4 As shown, according to Figure 4 The actual pore size n of the carbon molecular sieve is inferred from the isotherm curve i In the range of 4.2 to 4.3 Å, △n=|n i -n0|≤0.3 Å.

[0092] (4) The carbon molecular sieve obtained in step (3) was used for the separation of C3H6 / C3H8, and the adsorption isotherms of C3H6 and C3H8 at 298K were measured using a 3Flex three-station gas adsorption instrument from Micromeritics, USA. Figure 4As shown. The results show that the carbon molecular sieve has an obvious screening effect on C3H6 / C3H8, with a selectivity of 22, proving that its pore size is between the kinetic diameters of C3H6 and C3H8. Under the conditions of 298K and 1bar, the adsorption capacity of the carbon molecular sieve for C2H4 is as high as 2.1mmol / g, proving that it has the ability to extract high-purity C3H6 from the C3 binary component. The carbon molecular sieve was further used for the dynamic separation of C3H6 / C3H8 mixed gas. The specific experimental process is: at room temperature, the C3H6 / C3H8 (volume ratio 1:1) mixed gas is passed through a fixed bed filled with adsorption material at a flow rate of 1ml / min, and the filler is 500mg of adsorbent. The effluent gas from the fixed bed is analyzed by GC-6600 gas chromatograph and hydrogen flame ionization detector (FID). The resulting permeation curve is shown as follows. Figure 5 As shown in the figure, it can be seen that the non-adsorbed C3H8 flows out first, and C3H6 flows out after the adsorbent is saturated with adsorption. The separation time of C3H6 and C3H8 exceeds 52min / g, indicating that the carbon molecular sieve has excellent C3H6 / C3H8 separation performance.

[0093] Example 3

[0094] (1) The separation gas system was determined to be C3F6 / C3F8, and the target pore size n0 of the required carbon molecular sieve was 5.4Å.

[0095] (2) Phenolic resin was selected as the raw material and purchased from Borun New Material Technology Co., Ltd., item number 2123A.

[0096] The phenolic resin was heated to 200°C in air at a temperature of 5°C / min and kept pre-oxidized for 6 hours to obtain a pre-oxidized phenolic resin. The S0=sp 2 / sp 3 The value is 1.04.

[0097] (3) Since the target pore size n0 of carbon molecular sieve is 5.4Å, in the range of 5 to 10Å, substitute S0=1.04 and n0=5.4Å into formula (2) to calculate the carbonization temperature T i =849℃;

[0098] Select a carbon dioxide atmosphere, and program the temperature of the pre-oxidized phenolic resin in step (2) to 849°C at 5°C / min under a carbon dioxide atmosphere with a gas flow rate of 60 ml / min and maintain it for 1 hour, and then naturally cool it to room temperature to obtain a carbon molecular sieve with a pore size distribution as shown in FIG. Figure 6 As shown, the actual aperture n i is 5.4Å, satisfying △n=|n i -n0|≤0.3 Å.

[0099] (4) The carbon molecular sieve obtained in step (3) was used for the separation of C3F6 / C3F8, and the adsorption isotherms of C3F6 and C3F8 at 298K were measured using a 3Flex three-station gas adsorption instrument from Micromeritics, USA. Figure 7 As shown. The results show that the carbon molecular sieve has a certain screening effect on C3F6 / C3F8, with a selectivity of 7 and an adsorption capacity of C3F6 of 1.9mmol / g at 1bar. The carbon molecular sieve was further used for the dynamic separation of C3F6 / C3F8 mixed gas. The specific experimental process is: at room temperature, the C3F6 / C3F8 (volume ratio 1:999) mixed gas is passed through a fixed bed filled with adsorption material at a flow rate of 10ml / min. The filler is 500mg of adsorbent, and the fixed bed outflow gas is analyzed by GC-6600 gas chromatograph and hydrogen flame ionization detector (FID). The obtained permeation curve is shown as follows: Figure 8 As shown in the figure, it can be seen that C3F8, which has a weaker interaction with the adsorbent, flows out first, while C3F6, which has a stronger interaction with the adsorbent, flows out after adsorption saturation. The separation time of C3F6 and C3F8 exceeds 1300 min / g, indicating that the carbon molecular sieve has the excellent performance of removing trace C3F6 impurities in C3F6 / C3F8 mixed gas and purifying C3F8 in one step.

[0100] Example 4

[0101] (1) The separation gas system was determined to be C2ClF5 / C3F8, and the target pore size n0 of the required carbon molecular sieve was 5.6 Å.

[0102] (2) Phenolic resin was selected as the raw material and purchased from Dahui Chemical Technology Co., Ltd., product number 2123B.

[0103] The phenolic resin was heated to 150°C in an air atmosphere at a rate of 5°C / min and kept pre-oxidized for 4 hours to obtain a pre-oxidized phenolic resin. The S0=sp 2 / sp 3 The value is 1.13.

[0104] (3) Since the target pore size n0 of carbon molecular sieve is 5.6Å, in the range of 5 to 10Å, substitute S0=1.13 and n0=5.6Å into formula (2) to calculate the carbonization temperature T i =901℃;

[0105] Select a carbon dioxide atmosphere, and program the temperature of the pre-oxidized phenolic resin in step (2) to 901°C at 5°C / min under a carbon dioxide atmosphere with a gas flow rate of 60 ml / min and maintain it for 2 hours, and then naturally cool it to room temperature to obtain a carbon molecular sieve with a pore size distribution as shown in FIG. Figure 9 As shown, the actual aperture n i is 5.6Å, satisfying △n=|n i -n0|≤0.3 Å.

[0106] (4) The carbon molecular sieve obtained in step (3) was used for the separation of C2ClF5 / C3F8, and the adsorption isotherms of C2ClF5 and C3F8 at 298K were measured using a 3Flex three-station gas adsorption instrument from Micromeritics, USA. Figure 10 As shown. The results show that the carbon molecular sieve has a certain separation effect on C2ClF5 / C3F8, with a selectivity of 2.6 and an adsorption capacity of C2ClF5 of 1.6mmol / g at 1bar. The carbon molecular sieve was further used for the dynamic separation of C2ClF5 / C3F8 mixed gas. The specific experimental process is: at room temperature, the C2ClF5 / C3F8 (volume ratio 1:9999) mixed gas is passed through a fixed bed filled with adsorption material at a flow rate of 2ml / min. The filler is 500mg of adsorbent, and the fixed bed effluent gas is analyzed by GC-6600 gas chromatograph and hydrogen flame ionization detector (FID). The obtained permeation curve is shown as follows: Figure 11 As shown in the figure, it can be seen that C3F8, which has a weaker interaction with the adsorbent, flows out first, while C2ClF5, which has a stronger interaction with the adsorbent, flows out after adsorption saturation. The separation time of C2ClF5 and C3F8 exceeds 180 min / g, indicating that the carbon molecular sieve has the excellent performance of removing trace C2ClF5 impurities in C2ClF5 / C3F8 mixed gas and purifying C3F8 in one step.

[0107] Example 5

[0108] (1) The separation gas system was determined to be NF3 / CF4, and the target pore size n0 of the required carbon molecular sieve was 4.7 Å.

[0109] (2) Phenolic resin was selected as the raw material and purchased from Dahui Chemical Technology Co., Ltd., product number 2123B.

[0110] Determination of S0=sp of phenolic resin by X-ray photoelectron spectroscopy 2 / sp 3 The value is 1.35.

[0111] (3) Since the target pore size n0 of carbon molecular sieve is 4.7Å, in the range of 3 to 5Å, substitute S0=1.35 and n0=4.7Å into formula (1) to calculate the carbonization temperature T i =961℃;

[0112] Select nitrogen atmosphere, and heat the phenolic resin pre-oxidized in step (2) to 961°C at 5°C / min and maintain for 3 hours under nitrogen atmosphere with a gas flow rate of 60 ml / min, and then cool naturally to room temperature to obtain a carbon molecular sieve; the pore size distribution of the carbon molecular sieve is as follows Figure 12 As shown, the actual aperture n i is 5.4 Å, n i -n0=0.7 Å, does not satisfy △n=|n i -n0|≤0.3 Å, so the carbonization temperature T i Raise the temperature by 25°C and then continue to carbonize the precursor in step (2) again. The specific steps are as follows:

[0113] Continuing to select nitrogen atmosphere, the phenolic resin pre-oxidized in step (2) was heated to 986°C at 5°C / min and maintained for 3 hours under nitrogen atmosphere with a gas flow rate of 60 ml / min, and then naturally cooled to room temperature to obtain a carbon molecular sieve. The adsorption isotherm of the carbon molecular sieve is as follows: Figure 13 As shown, according to Figure 13 The actual pore size n of the carbon molecular sieve is inferred from the isotherm curve i In the range of 4.6 to 4.9 Å, △n=|n i -n0|≤0.3 Å.

[0114] (4) The carbon molecular sieve obtained by carbonization at 986°C in step (3) was used for NF3 / CF4 separation. The adsorption isotherms of NF3 and CF4 at 298K were measured using a 3Flex three-station gas adsorption instrument produced by Micromeritics, USA. Figure 13 As shown. The results show that the carbon molecular sieve has a significant screening effect on NF3 / CF4, with a selectivity of 12, proving that its pore size is between the kinetic diameters of NF3 and CF4. The carbon molecular sieve was further used for the dynamic separation of NF3 / CF4 mixed gas. The specific experimental process is: at room temperature, the NF3 / CF4 (CF4=20ppm) mixed gas is passed through a fixed bed filled with adsorption material at a flow rate of 2mL / min. The filler is 200mg of adsorbent, and the gas flowing out of the fixed bed is analyzed by gas chromatography with a thermal conductivity detector (TCD). The curve of the change of the outlet concentration over time is shown as follows: Figure 14 As shown in the figure, it can be seen that the NF3 residence time reaches 14min / g, and 6N purity NF3 can be obtained by desorption, indicating that the carbon molecular sieve has excellent NF3 / CF4 separation performance.

[0115] Example 6

[0116] (1) The separation gas system was determined to be C3H8 / CH3F, and the target pore size n0 of the required carbon molecular sieve was 5.9Å.

[0117] (2) Phenolic resin was selected as the raw material and purchased from Henan Jinrun New Materials Co., Ltd., item number 2123F.

[0118] The phenolic resin was heated to 170°C in air at a temperature of 5°C / min and kept pre-oxidized for 3 hours to obtain a pre-oxidized phenolic resin. The S0=sp 2 / sp 3 The value is 1.11.

[0119] (3) Since the target pore size n0 of carbon molecular sieve is 5.9Å, in the range of 5 to 10Å, substitute S0=1.11 and n0=5.9Å into formula (2) to calculate the carbonization temperature T i =924℃;

[0120] Select a carbon dioxide atmosphere, and program the temperature of the pre-oxidized phenolic resin in step (2) to 924°C at a gas flow rate of 60 ml / min at 5°C / min and maintain for 1 hour, and then naturally cool to room temperature to obtain a carbon molecular sieve. The pore size distribution of the carbon molecular sieve is as follows: Figure 15 As shown, the actual aperture n i is 6.4 Å, n i -n0=0.5 Å, does not satisfy △n=|n i -n0|≤0.3 Å, so the carbonization temperature T i Lower the temperature by 25°C and then continue to use the precursor in step (2) to re-carbonize. The specific steps are as follows:

[0121] Continuing to select the carbon dioxide atmosphere, the phenolic resin pre-oxidized in step (2) was heated to 899°C at 5°C / min and maintained for 1 hour under the carbon dioxide atmosphere with a gas flow rate of 60 ml / min, and then naturally cooled to room temperature to obtain a carbon molecular sieve with a pore size distribution as shown in FIG. Figure 16 As shown, the actual aperture n i is 5.9Å, satisfying △n=|n i -n0|≤0.3 Å .

[0122] (4) The carbon molecular sieve obtained by carbonization at 899°C in step (3) was used for the separation of C3H8 / CH3F. The adsorption isotherms of C3H8 and CH3F at 298K were measured using a 3Flex three-station gas adsorption instrument from Micromeritics, USA. Figure 17As shown. The results show that the carbon molecular sieve has a stronger adsorption effect on C3H8 than CH3F, especially at low pressure (0.01 bar), the selectivity of C3H8 / CH3F is as high as 60. The carbon molecular sieve is further used for the dynamic separation of C3H8 / CH3F mixed gas. The specific experimental process is: at room temperature, the C3H8 / CH3F (C3H8=100ppm) mixed gas is passed through a fixed bed filled with adsorption material at a flow rate of 5ml / min. The filler is 200mg of adsorbent, and the fixed bed effluent gas is analyzed using a GC-6600 gas chromatograph and a hydrogen flame ionization detector (FID). The resulting permeation curve is shown as follows: Figure 18 As shown in the figure, the residence time of C3H8 is as long as 750min / g, and the production of CH3F above 6N is 3500L / kg, indicating that the carbon molecular sieve has the ability to remove trace C3H8 impurities in the C3H8 / CH3F mixture and purify CH3F in one step.

[0123] Example 7

[0124] (1) The separation gas system was determined to be C2H4 / C2H6, and the target pore size n0 of the required carbon molecular sieve was 4.1Å.

[0125] (2) Phenolic resin was selected as the raw material and purchased from Borun New Materials Technology Co., Ltd., item number 2123C.

[0126] The phenolic resin was heated to 100°C in air at a temperature of 5°C / min and kept pre-oxidized for 3 hours to obtain a pre-oxidized phenolic resin. The S0=sp 2 / sp 3 The value is 1.25.

[0127] (3) Since the target pore size n0 of carbon molecular sieve is 4.1Å, in the range of 3 to 5Å, substituting S0=1.25 and n0=4.1Å into formula (1), the carbonization temperature T is calculated. i =1049℃;

[0128] Select nitrogen atmosphere, and heat the phenolic resin pre-oxidized in step (2) to 1049°C at 5°C / min and maintain for 1 hour under nitrogen atmosphere with a gas flow rate of 60 ml / min, and then cool naturally to room temperature to obtain a carbon molecular sieve. The adsorption isotherm of the carbon molecular sieve is as follows: Figure 19 As shown, according to Figure 19 The actual pore size n of the carbon molecular sieve is inferred from the isotherm curve i In the range of 4.0 to 4.1 Å, △n=|n i -n0|≤0.3 Å.

[0129] (4) The carbon molecular sieve obtained in step (3) was used for the separation of C2H4 / C2H6, and the adsorption isotherms of C2H4 and C2H6 at 298K were measured using a 3Flex three-station gas adsorption instrument from Micromeritics, USA. Figure 19 As shown. The results show that the carbon molecular sieve has an obvious screening effect on C2H4 / C2H6, with a selectivity of 6, proving that its pore size is between the kinetic diameters of C2H4 and C2H6. Under the conditions of 298K and 1bar, the adsorption capacity of the carbon molecular sieve for C2H4 is as high as 2.2mmol / g, proving that it has the ability to extract high-purity C2H4 from the C2 binary component. The carbon molecular sieve was further used for the dynamic separation of C2H4 / C2H6 mixed gas. The specific experimental process is: at room temperature, the C2H4 / C2H6 (volume ratio 1:1) mixed gas is passed through a fixed bed filled with adsorption material at a flow rate of 1ml / min, and the filler is 700mg of adsorbent. The effluent gas from the fixed bed is analyzed by GC-6600 gas chromatograph and hydrogen flame ionization detector (FID). The resulting permeation curve is shown as follows. Figure 20 As shown in the figure, it can be seen that C2H6 flows out first, and C2H4 flows out after the adsorbent is saturated with adsorption. The separation time of C2H4 and C2H6 exceeds 48min / g, indicating that the carbon molecular sieve has excellent C2H4 / C2H6 separation performance.

[0130] Example 8

[0131] (1) The separation gas system was determined to be C3F6 / C3F8, and the target pore size n0 of the required carbon molecular sieve was 5.4Å.

[0132] (2) Phenolic resin was selected as the raw material and purchased from Borun New Materials Technology Co., Ltd., item number 2123C.

[0133] The phenolic resin was heated to 250°C at 5°C / min in air atmosphere and kept pre-oxidized for 6 hours to obtain pre-oxidized phenolic resin; the S0=sp of the phenolic resin was determined by X-ray photoelectron spectroscopy. 2 / sp 3 The value is 0.95.

[0134] (3) Since the target pore size n0 of carbon molecular sieve is 5.4Å, in the range of 5 to 10Å, substitute S0 = 0.95 and n0 = 5.4Å into formula (2) to calculate the carbonization temperature T i =818℃;

[0135] Select a carbon dioxide atmosphere, and program the temperature of the pre-oxidized phenolic resin in step (2) to 818°C at 5°C / min under a carbon dioxide atmosphere with a gas flow rate of 60 ml / min and maintain it for 1 hour, and then naturally cool it to room temperature to obtain a carbon molecular sieve with a pore size distribution as shown in FIG. Figure 21 As shown, the actual aperture n i is 5.3Å, satisfying △n=|n i -n0|≤0.3 Å.

[0136] (4) The carbon molecular sieve obtained in step (3) was used for the separation of C3F6 / C3F8, and the adsorption isotherms of C3F6 and C3F8 at 298K were measured using a 3Flex three-station gas adsorption instrument from Micromeritics, USA. Figure 22 As shown. The results show that the carbon molecular sieve has a certain screening effect on C3F6 / C3F8, with a selectivity of 12 and an adsorption capacity of C3F6 of 1.8mmol / g at 1bar. The carbon molecular sieve was further used for the dynamic separation of C3F6 / C3F8 mixed gas. The specific experimental process is: at room temperature, the C3F6 / C3F8 (volume ratio 1:999) mixed gas is passed through a fixed bed filled with adsorption material at a flow rate of 4ml / min. The filler is 100mg of adsorbent, and the fixed bed effluent gas is analyzed by GC-6600 gas chromatograph and hydrogen flame ionization detector (FID). The obtained permeation curve is shown as follows: Figure 23 As shown in the figure, it can be seen that C3F8, which has a weaker interaction with the adsorbent, flows out first, and C3F6, which has a stronger interaction with the adsorbent, flows out after adsorption saturation. The separation time of C3F6 and C3F8 exceeds 1800 min / g, indicating that the carbon molecular sieve has the excellent performance of removing trace C3F6 impurities in C3F6 / C3F8 mixed gas and purifying C3F8 in one step.

[0137] Table 2 Experimental conditions of Examples 9 to 14

[0138]

[0139] Example 9

[0140] (1) The target pore size n0 of the carbon molecular sieve was determined to be 3.0, and phenolic resin was used as the raw material (purchased from Borun New Materials Technology Co., Ltd., product number 2123D).

[0141] (2) The phenolic resin was heated to 300°C at a rate of 5°C / min in an air atmosphere and kept pre-oxidized for 6 hours to obtain a pre-oxidized phenolic resin; the S0=sp of the phenolic resin was determined by X-ray photoelectron spectroscopy. 2 / sp 3 The value is 0.81.

[0142] (3) Since the target pore size n0 of carbon molecular sieve is 3.0Å, in the range of 3 to 5Å, substitute S0 and n0 into formula (1) to calculate the carbonization temperature T i =1274℃;

[0143] Select nitrogen atmosphere, and heat the phenolic resin pre-oxidized in step (2) to 1274°C at 5°C / min and maintain for 1 hour under nitrogen atmosphere with a gas flow rate of 60 ml / min, and then cool naturally to room temperature to obtain a carbon molecular sieve. The pore size distribution of the carbon molecular sieve is shown in FIG. Figure 24 ; The results show that the actual pore size n of carbon molecular sieve i Near 3.0Å, △n=|n i -n0|≤0.3 Å; this indicates that the carbon molecular sieve with the target pore size was successfully prepared through the above steps.

[0144] Example 10

[0145] (1) The target pore size n0 of the carbon molecular sieve was determined to be 5.0, and phenolic resin was used as the raw material (purchased from Borun New Materials Technology Co., Ltd., product number 2123E).

[0146] (2) Determination of S0=sp of phenolic resin by X-ray photoelectron spectroscopy 2 / sp 3 The value is 1.45.

[0147] (3) Since the target pore size n0 of carbon molecular sieve is 5.0Å, in the range of 3 to 5Å, substitute S0 and n0 into formula (1) to calculate the carbonization temperature T i =905℃;

[0148] Select nitrogen atmosphere, and heat the phenolic resin pre-oxidized in step (2) to 905°C at 5°C / min and keep it for 2h under nitrogen atmosphere with a gas flow rate of 60ml / min, and then cool it naturally to room temperature to obtain a carbon molecular sieve. The pore size distribution of the carbon molecular sieve is shown in FIG. Figure 24 ; The results show that the actual pore size n of carbon molecular sieve i is 5.0Å, satisfying △n=|n i -n0|≤0.3 Å; this indicates that the carbon molecular sieve with the target pore size was successfully prepared through the above steps.

[0149] Example 11

[0150] (1) The target pore size of the required carbon molecular sieve, n0 = 5.0, was selected, and phenolic resin was used as the raw material (purchased from Borun New Materials Technology Co., Ltd., product number 2123G).

[0151] (2) The phenolic resin was heated to 250°C at a rate of 5°C / min in an air atmosphere and kept pre-oxidized for 4 hours to obtain a pre-oxidized phenolic resin; the S0=sp of the pre-oxidized phenolic resin was determined by X-ray photoelectron spectroscopy. 2 / sp 3 The value is 0.96.

[0152] (3) Since the target pore size n0 of carbon molecular sieve is 5.0Å, in the range of 5 to 10Å, substituting S0=0.96 and n0=5.0Å into formula (2), the carbonization temperature T is calculated. i =781℃;

[0153] The phenolic resin pre-oxidized in step (2) was heated to 781°C at 5°C / min and maintained for 1 hour under a carbon dioxide atmosphere at a gas flow rate of 60 ml / min, and then naturally cooled to room temperature to obtain a carbon molecular sieve having a pore size distribution of Figure 25 ; The results show that the actual pore size n of carbon molecular sieve i is 5.0Å, satisfying △n=|n i -n0|≤0.3 Å; this indicates that the carbon molecular sieve with the target pore size was successfully prepared through the above steps.

[0154] Example 12

[0155] (1) The target pore size of the required carbon molecular sieve, n0 = 6.6, was selected, and phenolic resin was used as the raw material (purchased from Borun New Materials Technology Co., Ltd., product number 2123G).

[0156] (2) The phenolic resin was heated to 200°C at a rate of 5°C / min in an air atmosphere and kept pre-oxidized for 5 hours to obtain a pre-oxidized phenolic resin; the S0=sp of the pre-oxidized phenolic resin was determined by X-ray photoelectron spectroscopy. 2 / sp 3 The value is 1.02.

[0157] (3) Since the target pore size n0 of carbon molecular sieve is 6.6Å, in the range of 5 to 10Å, substitute S0=1.02 and n0=6.6Å into formula (2) to calculate the carbonization temperature T i =962℃;

[0158] The phenolic resin pre-oxidized in step (2) was heated to 962°C at 5°C / min and maintained for 2 hours under a carbon dioxide atmosphere at a gas flow rate of 60 ml / min, and then naturally cooled to room temperature to obtain a carbon molecular sieve having a pore size distribution of Figure 25 ; The results show that the actual pore size n of carbon molecular sieve i is 6.8Å, satisfying △n=|n i-n0|≤0.3 Å; this indicates that the carbon molecular sieve with the target pore size was successfully prepared through the above steps.

[0159] Example 13

[0160] (1) The target pore size of the required carbon molecular sieve, n0 = 8.2, was selected, and phenolic resin was used as the raw material (purchased from Borun New Materials Technology Co., Ltd., product number 2123G).

[0161] (2) The phenolic resin was heated to 300°C at a rate of 5°C / min in an air atmosphere and kept pre-oxidized for 6 hours to obtain a pre-oxidized phenolic resin; the S0=sp of the pre-oxidized phenolic resin was determined by X-ray photoelectron spectroscopy. 2 / sp 3 The value is 0.84.

[0162] (3) Since the target pore size n0 of carbon molecular sieve is 8.2Å, in the range of 5 to 10Å, substituting S0=0.84 and n0=8.2Å into formula (2), the carbonization temperature T is calculated. i =1059℃;

[0163] The phenolic resin pre-oxidized in step (2) was heated to 1059°C at 5°C / min and maintained for 1 hour under a carbon dioxide atmosphere at a gas flow rate of 60 ml / min, and then naturally cooled to room temperature to obtain a carbon molecular sieve having a pore size distribution of Figure 25 ; The results show that the actual pore size n of carbon molecular sieve i is 8.0Å, satisfying △n=|n i -n0|≤0.3 Å; this indicates that the carbon molecular sieve with the target pore size was successfully prepared through the above steps.

[0164] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A method for regulating the pore size of a carbon molecular sieve, characterized in that: The following steps are involved: (1) Using a thermosetting polymer as raw material, determining the parameter S0 of the thermosetting polymer and the target pore size n0 of the carbon molecular sieve; Where S0 is sp 2 With sp 3 The ratio of (2) If n0 is Within the range, substitute S0 and n0 into formula (1) to calculate the carbonization temperature T i , the thermosetting polymer is placed in a nitrogen and / or argon atmosphere and the carbonization temperature T i Carbonization treatment was carried out under the condition of i carbon molecular sieves; n=17.17-2.4S-0.0096T (1) If n0 is Within the range, substitute S0 and n0 into formula (2) to calculate the carbonization temperature T i , the thermosetting polymer is placed in a carbon dioxide atmosphere and the carbonization temperature T i Carbonization treatment was carried out under the condition of i carbon molecular sieves; n=0.55-3.5S+0.01T (2) In formulas (1) to (2), n is the main pore size of the carbon molecular sieve, in angstroms; S is the structural order of the thermosetting polymer, expressed in sp 2 With sp 3 The ratio of is expressed as; T is the carbonization temperature, in degrees Celsius; (3) If Then the carbon molecular sieve with the target pore size is obtained; otherwise, the carbonization temperature T is adjusted. i The thermosetting polymer is carbonized in the corresponding gas atmosphere and the adjusted carbonization temperature until Obtaining a carbon molecular sieve with a target pore size; Step (3) adjusting the carbonization temperature T i The carbonization temperature T i Adjust up and down 20 to 30 degrees Celsius; The thermosetting polymer in step (1) is at least one of a phenolic resin and a pre-oxidized phenolic resin; The range of the parameter S0 in step (1) is 0.8 to 1.

6.

2. The method for controlling the pore size of a carbon molecular sieve according to claim 1, wherein: The range of n0 in step (1) is 3. The method for controlling the pore size of a carbon molecular sieve according to claim 2, wherein: The range of n0 in step (1) is And / or, the parameter S0 in step (1) ranges from 0.8 to 1.

45.

4. The method for controlling the pore size of a carbon molecular sieve according to claim 3, wherein: The range of n0 in step (1) is And / or, the parameter S0 in step (1) ranges from 1.0 to 1.

4.

5. The method for controlling the pore size of a carbon molecular sieve according to claim 1 or 2, characterized in that: The pre-oxidation treated phenolic resin is obtained by the following method: carbonizing the phenolic resin in an oxygen-containing atmosphere at 100-300° C. for 0-6 hours, wherein the carbonization time is not zero.

6. The method for controlling the pore size of a carbon molecular sieve according to claim 5, characterized in that: The oxygen-containing atmosphere is air; and / or, the phenolic resin is carbonized in an air atmosphere at 100-300° C. for 3-6 hours; And / or, the programmed heating rate of the pre-oxidation treatment is 3 to 15° C. / min.

7. The method for controlling the pore size of a carbon molecular sieve according to claim 6, wherein: The phenolic resin is carbonized in an air atmosphere at 100-250° C. for 3-6 hours.

8. The method for controlling the pore size of a carbon molecular sieve according to claim 1 or 2, characterized in that: The temperature of the carbonization treatment in step (2) is 600-1600° C. And / or, the carbonization treatment time in step (2) is 0.5 to 3 hours; And / or, the programmed heating rate of the carbonization treatment in step (2) is 3 to 15°C / min; And / or, during the carbonization treatment in step (2), the gas flow rates of nitrogen and / or argon and carbon dioxide are all 10 to 1000 ml / min.

9. The method for controlling the pore size of a carbon molecular sieve according to claim 8, characterized in that: The temperature of the carbonization treatment in step (2) is 780-1274°C; And / or, the carbonization treatment time in step (2) is 0.5 to 3 hours.

10. The method for controlling the pore size of a carbon molecular sieve according to claim 9, characterized in that: The temperature of the carbonization treatment in step (2) is 818-1100° C. And / or, the carbonization treatment time in step (2) is 1 to 2 hours.

11. The method for controlling the pore size of a carbon molecular sieve according to claim 1 or 2, characterized in that: Step (3) adjusting the carbonization temperature T i The carbonization temperature T i Adjust up and down 20 to 30 degrees Celsius; Specifically: If the atmosphere is nitrogen and / or argon, when the measured aperture n i When the pore size n0 is larger than the target pore size, the carbonization temperature is increased by 20 to 30°C. i When the pore size is smaller than the target pore size n0, the carbonization temperature is lowered by 20-30°C; if the atmosphere is carbon dioxide, when the measured pore size n i When the pore size is smaller than the target pore size n0, the carbonization temperature is increased by 20 to 30°C. i When the pore size is larger than the target pore size n0, the carbonization temperature is lowered by 20 to 30°C.

12. The pore size obtained by the control method according to any one of claims 1 to 11 is Tunable carbon molecular sieve.

13. Use of the carbon molecular sieve obtained by the control method according to any one of claims 1 to 11 in the separation or purification of fluorine-containing electronic specialty gas systems.

14. The use according to claim 13, characterized in that The fluorine-containing electronic special gas system is one of C3H8 / CH3F, NF3 / CF4, C2ClF5 / C2HF5, C2ClF5 / C3F8, and C3F6 / C3F8.

15. The use according to claim 14, characterized in that: The fluorine-containing electronic special gas system is one of C3H8 / CH3F, NF3 / CF4, C2ClF5 / C3F8, and C3F6 / C3F8.

16. A method for gas separation using carbon molecular sieve, characterized in that: The following steps are involved: (1) Determine the target gas system to be separated and the target pore size n0 required by the carbon molecular sieve; (2) Obtaining a carbon molecular sieve with a target pore size according to the method for controlling the pore size of a carbon molecular sieve according to any one of claims 1 to 11; (3) Using carbon molecular sieves with target pore size for separation of target gas systems; The target gas system in step (1) is a fluorine-containing electronic specialty gas system.

17. The method according to claim 16, characterized in that The fluorine-containing electronic special gas system is one of C3H8 / CH3F, NF3 / CF4, C2ClF5 / C2HF5, C2ClF5 / C3F8, and C3F6 / C3F8.

18. The method according to claim 16 or 17, characterized in that: The method for separating the target gas system in step (3) is as follows: at room temperature, the target gas system is passed through a fixed bed filled with a carbon molecular sieve of target pore size at a certain flow rate, thereby achieving gas adsorption separation; And / or, the ratio of the target gas system flow rate to the carbon molecular sieve is 1-10 ml / min: 200-700 mg.

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