Organic silicon composition, organic silicon film, organic composite silicon film and preparation method and application thereof

Abstract

The invention provides an organic silicon composition, an organic silicon film, an organic composite silicon film and a preparation method and application thereof. The silicone composition includes a silicone sol and a hydrophobic additive. In the preparation method of the organic silicon composite silicon film, the hydrophobic additive is added into the organic silicon layer, so that the dissolution of water vapor in VOCs organic gas in the organic silicon film layer is reduced, the swelling of the film caused by the water vapor can be greatly improved and relieved, and the service life of the film is prolonged. Compared with a traditional membrane preparation method, the method has the advantages that the preparation process is simple and easy to regulate and control, a complicated post-treatment process can be avoided, a large amount of manpower and material resources are saved, and large-scale production is easy.

Description

Technical Field

[0001] The present invention relates to the technical field of organic gas separation membranes, and in particular to an organic silicon composition, an organic silicon membrane, an organic composite silicon membrane, and a preparation method and application thereof. Background Art

[0002] In recent years, with the improvement of energy conservation and environmental protection requirements and the requirements for increasing the utilization rate of product added value of chemical equipment, it is becoming increasingly demanding. As we all know, a large amount of tail gas and waste gas will be generated during the production, storage and transportation of chemical products, which are rich in organic gases such as VOCs. If these organic gases are directly discharged, they will cause environmental pollution. At present, they are usually discharged after being adsorbed by combustion and activated carbon adsorbents. The combustion method will produce more carbon dioxide and does not meet the current carbon emission requirements. Although the adsorption method can meet the requirements, it is limited by the adsorption capacity of the adsorbent and needs to be replaced frequently. In addition, the regeneration and replacement of the adsorbent after treatment is also a major economic and environmental problem. Therefore, membrane adsorption separation technology has received more and more attention. Membrane adsorption separation technology is low in cost, green and efficient, low in carbon and environmentally friendly, energy-saving and consumption-reducing. At the same time, it can separate the waste VOCs organic gas and recycle it to generate greater economic benefits.

[0003] VOCs organic gas separation membrane uses the rubbery polymer macromolecules on the membrane surface and the organic gas molecules to absorb and desorb by similar compatibility, and quickly diffuses through the cross-linked pores to finally preferentially permeate the membrane. In membrane adsorption separation technology, membrane materials are the core part of the technology and the key to achieving VOCs organic gas separation. Gas separation membranes can be divided into organic membranes and inorganic membranes according to the raw materials used to prepare the membranes. Inorganic membranes have relatively good performance, high mechanical strength and good thermal stability, but the preparation process is complex, the cost is high, the reproducibility is poor, and large-scale industrial applications are difficult. Organic membranes have the advantages of low cost, good performance and good ductility, and have been applied in large-scale industry, but they also have the disadvantages of poor stability and poor mechanical strength. Therefore, organic-inorganic composite membranes have become the target of people's research and pursuit, and have also been successively applied in industry. Especially in the separation of VOCs organic gases, it has also been applied.

[0004] However, there is usually a certain amount of water vapor in VOCs organic gas, which will cause the membrane to swell, resulting in a decrease in membrane separation performance and shortening the life of the membrane. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide an organosilicon composition, an organosilicon membrane, an organic composite silicon membrane and a preparation method and application thereof. By adding a hydrophobic substance to the rubbery organosilicon membrane layer, water vapor is prevented from entering the organosilicon membrane layer as much as possible and flows out from the non-permeable layer with the inert gas, which can greatly improve and alleviate the swelling of the membrane caused by water vapor and extend the life of the membrane, thereby solving the problem of swelling of the organosilicon membrane layer caused by water vapor, and further making the organosilicon membrane have higher separation performance index and life.

[0006] In a first aspect, the present invention provides an organosilica sol and a hydrophobic additive.

[0007] In some embodiments, the hydrophobic additive is one or more of ultrafine graphene, white carbon black, and carbon nanotubes.

[0008] In some embodiments, the particle size of the hydrophobic additive is 0.3-50 nm, for example, 0.3 nm, 1 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm.

[0009] In some embodiments, the particle size of the hydrophobic additive is 0.5-20 nm.

[0010] In some embodiments, the mass ratio of the hydrophobic additive to the organosilica sol is 1:(10-1000), for example, 1:10, 1:30, 1:50, 1:70, 1:90, 1:110, 1:130, 1:150, 1:170, 1:190, 1:200, 1:250, 1:300, 1:400, 1:500, 1:600, 1:700, 1:800, 1:900, 1:1000.

[0011] In some embodiments, the mass ratio of the hydrophobic additive to the organosilica sol is 1:(50-300).

[0012] In some embodiments, the mass ratio of the hydrophobic additive to the organosilica sol is 1:(50-200).

[0013] In some embodiments, the mass ratio of the hydrophobic additive to the organosilica sol is 1:(50-100).

[0014] In a second aspect, the present invention provides a method for preparing the organosilicon composition of the first aspect, comprising the steps of: mixing an organosilicon sol with a hydrophobic additive and heating the mixture to obtain the organosilicon composition.

[0015] In some embodiments, the heating temperature is 20-100°C, for example, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, or 100°C.

[0016] In some embodiments, in step (1), the heating temperature is 40 to 90°C.

[0017] In some embodiments, the heating time is 0.1 to 4 hours, for example, 0.1 h, 0.5 h, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, or 4 h.

[0018] In some embodiments, the heating time is 0.2 to 1 h.

[0019] In some embodiments, the method for preparing the organosilicon sol includes: mixing an organosilicon source precursor, alcohol, deionized water, and a catalyst to perform a hydrolysis polymerization reaction.

[0020] In some embodiments, the temperature of the hydrolysis polymerization reaction is 20-100°C, for example, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, or 100°C.

[0021] In some embodiments, the temperature of the hydrolysis polymerization reaction is 40-90°C.

[0022] In some embodiments, the hydrolysis polymerization reaction time is 1 to 6 hours, for example, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, or 6 hours.

[0023] In some embodiments, the hydrolysis polymerization reaction time is 2 to 4 hours.

[0024] In some embodiments, the method for preparing the organic silica sol includes: adding an organic silicon source precursor to alcohol, then adding deionized water dropwise at 20-100° C. under stirring conditions, and finally adding hydrochloric acid dropwise, and continuously heating and stirring at 20-100° C. for 1-6 hours to obtain the organic silica sol.

[0025] In some embodiments, the organosilicon precursor is a bridged oxygen silane.

[0026] In some embodiments, the organosilicon precursor is selected from one or a mixture of methyltriethoxysilane, 1,2-bis(triethoxysilyl)methane, 1,2-bis(triethoxysilyl)ethane, 1,2-bis(triethoxysilyl)ethylene and phenyltriethoxysilane.

[0027] In some embodiments, the catalyst is hydrochloric acid, and the concentration of the hydrochloric acid is 0.01-10wt%, for example, 0.01wt%, 0.1wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%.

[0028] In some embodiments, the alcohol is methanol, ethanol, n-propanol, isopropanol, or a mixture of several thereof.

[0029] In some embodiments, the mass ratio of the added amount of the alcohol to the organosilicon source precursor is (5-100):1, for example, 5:1, 10:1, 15:1, 20:1, 25:1, 30:1, 35:1, 40:1, 45:1, 50:1, 55:1, 60:1, 65:1, 70:1, 75:1, 80:1, 85:1, 90:1, 95:1, 100:1.

[0030] In some embodiments, the mass ratio of the alcohol added to the organosilicon source precursor is (10-50):1.

[0031] In some embodiments, the molar ratio of the organosilicon source precursor, deionized water, and hydrogen chloride in hydrochloric acid is 1:(30-120):(0.05-1), for example, 1:(30, 40, 50, 60, 70, 80, 90, 100, 110, 120):(0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1).

[0032] In some embodiments, the molar ratio of the organosilicon source precursor, deionized water, and hydrogen chloride in hydrochloric acid is 1:(50-90):(0.1-0.5).

[0033] In a third aspect, the present invention provides an organic silicon film, which is prepared by coating the organic silicon composition described in the first aspect.

[0034] In a fourth aspect, the present invention provides an organic composite silicon film, comprising a base film and the organic silicon film described in the third aspect.

[0035] In a fifth aspect, the present invention provides a method for preparing the organic composite silicon film described in the fourth aspect, comprising the following steps: coating the organic silicon composition described in the first aspect on a base film to obtain the organic composite silicon film.

[0036] In some embodiments, the coating process may be repeated 2-5 times depending on the film formation conditions.

[0037] In some embodiments, the coating method is any one of spray coating, blade coating or spin coating.

[0038] In some embodiments, the preparation method further comprises drying the organic composite silicon film.

[0039] In the following embodiments, the drying temperature is 20-180°C, for example, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, or 100°C.

[0040] In the following embodiment, the drying temperature is 60-150°C.

[0041] In some embodiments, the drying time is 5 min to 24 h, for example, 5 min, 0.5 h, 5 h, 10 h, 15 h, 20 h, or 24 h.

[0042] In some embodiments, the drying time is 10 min to 1 h.

[0043] In some embodiments, the method for preparing the basement membrane comprises:

[0044] S1, adding an organic high molecular polymer into a solvent, heating and stirring the mixture, and preparing a casting solution;

[0045] S2, coating the casting liquid obtained in step S1 on the casting body to obtain the base film.

[0046] In some embodiments, the organic high molecular polymer is selected from one or more of polysulfone, polyethersulfone, sulfonated polyethersulfone, polyimide, polyvinyl alcohol, and polypropylene.

[0047] In some embodiments, the solvent is one or more of N-methylpyrrolidone (NMP), dimethylformamide (DMF), and dimethylacetamide (DMAc).

[0048] In some embodiments, the mass ratio of the organic high molecular polymer to the solvent is (0.05-0.3):1; for example, 0.05:1, 0.1:1, 0.15:1, 0.2:1, 0.25:1, 0.3:1.

[0049] In some embodiments, the mass ratio of the organic high molecular polymer to the solvent is (0.1-0.2):1.

[0050] In some embodiments, in step S1, the heating temperature is 50-150°C, for example, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C.

[0051] In some embodiments, in step S1, the heating temperature is 50-90°C.

[0052] In some embodiments, in step S1, the heating time is 1-5 hours, for example, 1 hour, 2 hours, 3 hours, 4 hours, or 5 hours.

[0053] In some embodiments, in step S1, the heating time is 2-4 hours.

[0054] In some embodiments, in step S2, the coating method is any one of spray coating, scraper coating or spin coating.

[0055] In some embodiments, the method for preparing the base film further comprises drying the base film.

[0056] In some embodiments, the drying temperature is 50-180°C, for example, 50°C, 70°C, 90°C, 110°C, 130°C, 150°C, 170°C, or 180°C.

[0057] In some embodiments, the drying time is 5 min to 120 min, for example, 5 min, 20 min, 40 min, 60 min, 80 min, 100 min, or 120 min.

[0058] In some embodiments, the method for preparing the basement membrane comprises:

[0059] A, adding organic polymer particles into N-methylpyrrolidone solution, heating and stirring for 1-5 hours to dissolve into a casting solution of a certain concentration;

[0060] B. The casting liquid obtained in step A is coated on the smooth casting body by a coating method, and dried at 50 to 180° C. for 5 to 120 minutes to obtain the base film.

[0061] In some embodiments, the method for preparing the organic composite silicon film comprises the following steps:

[0062] (1) Adding a bridged oxygen silane as an organosilicon source precursor to an alcohol solution, then adding deionized water dropwise under heating and stirring conditions, the heating temperature is 20 to 100° C., and the stirring time is 1 to 6 hours; finally, hydrochloric acid is gradually added dropwise, and the organosilicon sol is obtained after continuous heating and stirring at 20 to 100° C. for 1 to 6 hours;

[0063] (2) adding a hydrophobic additive to the organosilicon sol gel of step (1), and continuing to heat and stir at 20 to 100° C. for 0.1 to 4 hours to prepare a blended organosilicon sol gel solution;

[0064] (3) The blended organic silicon sol-gel solution obtained in step (2) is coated on the base film by a coating method, and dried at 20 to 180° C. for 5 min to 24 h to obtain a preliminary organic flexible silicon film. Depending on the film formation conditions, this process can be repeated 2 to 5 times to finally obtain an organic silicon film.

[0065] In a sixth aspect, the present invention provides an application of the organic composite silicon membrane described in the fourth aspect in the field of gas separation, recovery and / or emission.

[0066] In the method for preparing the organic composite silicon membrane of the present invention, a hydrophobic additive is added to the organic silicon layer, which reduces the dissolution of water vapor in the VOCs organic gas in the organic silicon membrane layer, can greatly improve and alleviate the swelling of the membrane caused by water vapor, and extend the life of the membrane. Compared with the traditional membrane preparation method, this method has a simple preparation process, is easy to control, can avoid complicated post-processing processes, saves a lot of manpower and material resources, and is easy to produce on a large scale. The organic composite silicon membrane prepared by the present invention has good separation performance in the organic gas separation process and has high hydrothermal stability, and can be used in the industrial production of organic gas separation. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 is a SEM image of the flexible organic film in Example 1;

[0068] Figure 2 This is the SEM image of the composite silicon film in Example 1. DETAILED DESCRIPTION

[0069] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the embodiments and drawings. The specific embodiments described herein are only used to explain the present invention and are not intended to constitute any limitation to the present invention. In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concepts of the present disclosure. Such structures and technologies are also described in many publications.

[0070] Example 1

[0071] (1) Weigh 10 g of polyethersulfone and add it to 59 g of N-methylpyrrolidone solution. Stir it in a 75° C. water bath for 4 h until the particles are completely dissolved to prepare a 14.5% (wt) casting solution.

[0072] (2) Fix the cleaned copper foil (10 cm × 10 cm) on the coating machine, adjust the film thickness to 50-100 μm, weigh 5 mL of the film casting solution in step (1) and evenly apply it on one end of the copper foil, start the machine to scrape the film. Dry the film at 100°C for 10 min to form a flexible organic film, and its SEM is as follows: Figure 1 shown.

[0073] (3) Weigh 14.8 g of methyltriethoxysilane, add 300 g of isopropanol, add 120 g of deionized water dropwise under 60° C. water bath heating, then add 4 g of 10 wt% hydrochloric acid dropwise, stir for 4 hours, add 0.15 g of 10 nm graphene (the mass ratio of graphene to methyltriethoxysilane is 1:98), and continue stirring at 60° C. for 1 hour to prepare a blended organic silica sol-gel solution.

[0074] (4) Weigh 50 g of the mixed organic silicon sol-gel solution prepared in step (3) and spray it onto the flexible organic film prepared in step (2) by electrostatic spraying, and dry it at 100° C. for 30 min to prepare a composite silicon film. The SEM image of the composite silicon film is as follows: Figure 2 shown.

[0075] according to Figure 1 and Figure 2 It can be seen that Figure 1 The pores of the medium base membrane are larger and have no separation properties. Figure 2 The pores of the composite silicon membrane are relatively dense. In view of the pore size distribution, the composite silicon membrane of the present invention is a microporous structure with a pore size much smaller than 3 μm, which shows that the composite silicon membrane of the present invention has separation performance.

[0076] Example 2

[0077] Different from Example 1, in step (3), the particle size of graphene is 20 nm.

[0078] Example 3

[0079] Different from Example 1, in step (3), the particle size of graphene is 0.3 nm.

[0080] Example 4

[0081] Different from Example 1, in step (3), the particle size of graphene is 60 nm.

[0082] Example 5

[0083] Different from Example 1, in step (3), the amount of graphene added is 0.296 g (the mass ratio of graphene to methyltriethoxysilane is 1:50).

[0084] Example 6

[0085] Different from Example 1, in step (3), the amount of graphene added is 0.074 g (the mass ratio of graphene to methyltriethoxysilane is 1:200).

[0086] Example 7

[0087] Different from Example 1, in step (3), the amount of graphene added is 0.064 g (the mass ratio of graphene to methyltriethoxysilane is 1:230).

[0088] Example 8

[0089] Different from Example 1, in step (3), the amount of graphene added is 0.493 g (the mass ratio of graphene to methyltriethoxysilane is 1:30).

[0090] Example 9

[0091] Different from Example 1, in step (3), graphene is replaced by carbon nanotubes.

[0092] Example 10

[0093] Different from Example 1, in step (3), graphene is replaced by white carbon black.

[0094] Embodiment 11

[0095] The difference from Example 1 is that in step (3), 120 g of deionized water is added dropwise under heating in a 40° C. water bath.

[0096] Example 12

[0097] The difference from Example 1 is that in step (3), 120 g of deionized water is added dropwise under heating at 80° C. in a water bath.

[0098] Embodiment 13

[0099] The difference from Example 1 is that in step (3), 120 g of deionized water is added dropwise under heating at 90° C. in a water bath.

[0100] Embodiment 14

[0101] The difference from Example 1 is that in step (3), 120 g of deionized water is added dropwise under heating in an oil bath at 110°C.

[0102] Comparative Example 1

[0103] (1) Weigh 10 g of polyethersulfone and add it to 59 g of N-methylpyrrolidone solution. Stir it in a 75° C. water bath for 4 h until the particles are completely dissolved to prepare a 14.5% (wt) casting solution.

[0104] (2) Fix the cleaned copper foil (10 cm×10 cm) on the coating machine, adjust the film thickness to 50-100 μm, weigh 5 mL of the casting solution in step (1) and evenly coat it on one end of the copper foil, start the machine to scrape the film, and dry the film at 100°C for 10 min to form a flexible organic film.

[0105] (3) Weigh 14.8 g of methyltriethoxysilane, add 300 g of isopropanol, add 120 g of deionized water dropwise under 60° C. water bath heating, then add 4 g of 10 wt % hydrochloric acid dropwise, and stir for 4 hours to prepare an organic silicon sol-gel solution.

[0106] (4) Weigh 50 g of the organic silicon sol-gel solution prepared in step (3) and spray it onto the flexible organic film prepared in step (2) by electrostatic spraying, and dry it at 100° C. for 30 min to form a silicon film.

[0107] The composite silicon membrane prepared above was used to test the VOC oil and gas separation performance. The results are shown in Table 1. Test conditions: At room temperature, such as 25°C, with nitrogen entrainment of 5g / m 3 VOCs oil and gas are the raw gas, feed gas pressure: 0.30MPa, feed flow rate: 0.30L / m 2 / min, the vacuum degree on the permeate side is: 0.08MPa. After membrane separation, the VOCs oil and gas concentration coming out of the permeate side is ag / m 3 The VOCs concentration on the interception side is bg / m 3 , membrane separation selectivity X is a / b.

[0108] The oil and gas concentration is detected by meteorological chromatography.

[0109] Table 1

[0110]

[0111] According to Table 1, the organic composite membrane of the present invention significantly prolongs the life of the membrane. The separation selectivity in the example decreases less after 48 hours, while the separation performance of the comparative example 1 decreases significantly after 48 hours, decreasing by more than 30%, indicating that the life of the membrane in the comparative example 1 is significantly lower than that in the example.

[0112] According to Examples 1-3 and Comparative Example 1, the smaller the particle size of graphene, the better the separation selectivity.

[0113] It can be seen from Examples 1, 4-5 and Comparative Examples 3-4 that if the graphene content is too high, the separation selectivity deteriorates.

[0114] It can be seen from Examples 1, 8-10 and Comparative Example 5 that when the temperature of the reaction between the additive and the organosilica sol is too high, the separation selectivity becomes poor.

[0115] Since hydrophobic additives are added during the preparation of the organic composite membrane, the film formation process is more difficult. Therefore, the present invention prepares the organic composite silicon membrane by controlling the particle size, content, reaction temperature and time of the hydrophobic additive, so that the organic composite silicon membrane has higher permeability and separation coefficient.

[0116] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. An organosilicon composition comprising an organosilicon sol and a hydrophobic additive.

2. The organosilicon composition according to claim 1, characterized in that: The hydrophobic additive is one or more of ultrafine graphene, white carbon black, carbon nanotubes, and / or The particle size of the hydrophobic additive is 0.3-50 nm, preferably 0.5-20 nm; and / or The mass ratio of the hydrophobic additive to the organosilica sol is 1:(10-1000), preferably 1:(50-300).

3. A method for preparing the organosilicon composition according to claim 1 or 2, comprising the following steps: The organosilicon sol is mixed with a hydrophobic additive and heated to obtain the organosilicon composition.

4. The preparation method according to claim 3, characterized in that: The heating temperature is 20-100° C., preferably 40-90° C.; the heating time is 0.1-4 h, preferably 0.2-1 h.

5. The preparation method according to claim 3 or 4, characterized in that: The preparation method of the organosilicon sol comprises: mixing an organosilicon source precursor, alcohol, deionized water and a catalyst to perform a hydrolysis polymerization reaction; Preferably, the temperature of the hydrolysis polymerization reaction is 20 to 100° C., preferably 40 to 90° C.; the time of the hydrolysis polymerization reaction is 1 to 6 hours, preferably 2 to 4 hours.

6. The preparation method according to claim 5, characterized in that: The organosilicon precursor is a bridged oxygen silane; More preferably, the organosilicon precursor is selected from one or a mixture of methyltriethoxysilane, 1,2-bis(triethoxysilyl)methane, 1,2-bis(triethoxysilyl)ethane, 1,2-bis(triethoxysilyl)ethylene and phenyltriethoxysilane; and / or The catalyst is hydrochloric acid, and the concentration of the hydrochloric acid is 0.01-10 wt %; and / or The alcohol is one or a mixture of methanol, ethanol, n-propanol, isopropanol; Preferably, the mass ratio of the alcohol added to the organosilicon source precursor is (5-100):1, preferably (10-50):1; Preferably, the molar ratio of the organosilicon source precursor, deionized water, and hydrogen chloride in hydrochloric acid is 1:(30-120):(0.05-1), preferably 1:(50-90):(0.1-0.5).

7. An organic silicon film, prepared by coating the organic silicon composition according to claim 1 or 2. An organic composite silicon film comprising a base film and the organic silicon film according to claim 7.

9. A method for preparing the organic composite silicon film according to claim 8, comprising the following steps: Coating the organic silicon composition according to claim 1 or 2 on a base film to obtain the organic composite silicon film; Preferably, the coating method is any one of spray coating, scraper coating or spin coating; Preferably, the preparation method further comprises drying the organic composite silicon film, preferably, the drying temperature is 20 to 180° C., preferably 60 to 150° C.; the drying time is 5 min to 24 h, preferably 10 min to 1 h; Preferably, the method for preparing the base film comprises: S1, adding an organic high molecular polymer into a solvent, heating and stirring the mixture, and preparing a casting solution; S2, coating the casting liquid obtained in step S1 on the casting body to obtain the base film; Preferably, the organic high molecular polymer is selected from one or more of polysulfone, polyethersulfone, sulfonated polyethersulfone, polyimide, polyvinyl alcohol, and polypropylene; The solvent is one or more of N-methylpyrrolidone, dimethylformamide, and dimethylacetamide; Preferably, the mass ratio of the organic high molecular polymer to the solvent is (0.05-0.3):1, preferably (0.1-0.2):1; Preferably, in step S1, the heating temperature is 50-150° C., preferably 50-90° C.; the heating time is 1-5 h, preferably 2-4 h.

10. Use of the organic composite silicon membrane according to claim 8 in the field of gas separation, recovery and / or emission.

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