Carbon molecular sieve membranes based on anaerobic polymer precursors

Abstract

Embodiments of this disclosure provide a carbon molecular sieve membrane (and its precursor) comprising pyrolysis products of an intrinsically microporous, oxygen-free ladder polymer. Embodiments of this disclosure also provide a gas separation method comprising contacting a fluid comprising one or more gaseous components with a carbon molecular sieve membrane, wherein the carbon molecular sieve membrane comprises pyrolysis products of an intrinsically microporous, oxygen-free ladder polymer, and at least one of said gaseous components is separated from the fluid. Embodiments of this disclosure further provide a method for preparing a carbon molecular sieve membrane, comprising heating an intrinsically microporous, oxygen-free ladder polymer to a pyrolysis temperature in an oxygen-free atmosphere to optionally form pyrolysis products without generating any oxygen-containing gas.

Description

Background Technology

[0001] Membrane-based gas separation processes have been introduced, using polysulfone and cellulose acetate membranes to recover H2 from ammonia synthesis and remove CO2 from natural gas. Subsequently, membrane technology has expanded to air and hydrogen separation, natural gas desulfurization, and hydrocarbon recovery. Membrane-based gas separation processes continue to emerge in large-scale industrial applications, such as recovering hydrogen from nitrogen- and hydrocarbon-containing petrochemical process streams, on-site nitrogen generation (O2 / N2), and removing acid gases (CO2, H2S, etc.) from natural gas. Important potential future applications include the separation of olefins from paraffins, such as the separation of C2H4 from C2H6 and C3H6 from C3H8, and the removal of H2 from CO2 in various chemical processes. While advances in membrane technology have focused on new materials for more challenging and energy-intensive applications, efforts to develop materials with the ultra-high selectivity and high permeability required for such separation are ongoing. More specifically, membranes with strong chemical resistance and high mechanical strength, as well as high permeability and high selectivity, have not yet been achieved. Summary of the Invention

[0002] In one or more aspects of the present invention, a polymer precursor for manufacturing carbon molecular sieve membranes is provided. The polymer precursor for manufacturing carbon molecular sieve membranes may comprise an intrinsically microporous, oxygen-free ladder polymer.

[0003] In one or more other aspects of the invention, a carbon molecular sieve membrane is provided. The carbon molecular sieve membrane may comprise the pyrolysis products of an intrinsically microporous, oxygen-free ladder polymer.

[0004] In one or more other aspects of the present invention, a method for preparing a carbon molecular sieve membrane is provided. The method for preparing a carbon molecular sieve membrane may include one or more of the following steps: heating an intrinsically microporous oxygen-free ladder polymer to a pyrolysis temperature in an oxygen-free atmosphere; exposing the intrinsically microporous oxygen-free ladder polymer to the pyrolysis temperature for a predetermined duration; and cooling the intrinsically microporous oxygen-free ladder polymer to a second temperature.

[0005] In one or more other aspects of the invention, a gas separation method is provided. The gas separation method may include one or more of the following steps: contacting a fluid comprising one or more gaseous components with a carbon molecular sieve membrane, wherein the carbon molecular sieve membrane comprises pyrolysis products of an intrinsically microporous, anaerobic ladder polymer, and separating at least one of said gaseous components from the fluid. Attached Figure Description

[0006] Figure 1A-1BThe diagram shows (a) a schematic of the chemical transformation that occurs during pyrolysis, wherein the upper structure is a PIM-based polymer and the lower structure is a random turbine static CMS morphology; and (b) a graphical view illustrating the proposed transformation of the pore size distribution in a carbon molecular sieve to molecular-level pore size optimization according to one or more embodiments of the invention.

[0007] Figure 2 This is a flowchart of a pyrolysis scheme for preparing carbon molecular sieve membranes according to one or more embodiments of the present invention.

[0008] Figure 3 This is a flowchart of a gas separation method according to one or more embodiments of the present invention.

[0009] Figure 4 This is a schematic diagram illustrating the main factors affecting the size, size distribution, and interconnectivity of CMS membrane pores according to one or more embodiments of the present invention.

[0010] Figures 5A-5B This is a schematic diagram illustrating the gases generated during the pyrolysis of two precursor types according to one or more embodiments of the present invention, wherein (A) above represents the oxygen-containing precursor, and the mass spectrum represents the gases generated during the degradation of Kapton polyimide, and (B) below represents the oxygen-free precursor.

[0011] Figures 6A-6D This is a schematic diagram of the chemical structure of various polymer precursors (including intrinsically microporous oxygen-free ladder polymers) according to one or more embodiments of the present invention, and various graphical views showing the effect of deformation sites on the pore size of CMS membranes—the larger the deformation site, the larger the fine-tuning pore.

[0012] Figure 7 This is a schematic diagram of a three-zone tube furnace with an oxygen sensor for polymer pyrolysis according to one or more embodiments of the present invention.

[0013] Figure 8 This is a graphical view illustrating the heating scheme used in preparing CMS membranes from intrinsically microporous oxygen-free ladder polymers according to one or more embodiments of the present invention.

[0014] Figure 9 This is a graphical view illustrating the cooling scheme employed after pyrolysis when preparing a CMS membrane from an intrinsically microporous oxygen-free ladder polymer, according to one or more embodiments of the present invention.

[0015] Figures 10A-10BAccording to one or more embodiments of the present invention, (a) graphical views of the H2 / CO2 separation performance of CANAL-TB-1 raw material and its heat-treated derivatives; and (b) H2 / CO2 performance of CANAL-TB-1-based CMS membranes heat-treated at 800 to 900 °C compared with CMS membranes previously reported in the literature.

[0016] Figure 11 This is a graphical view showing a comparison of the C2H4 / C2H6 performance of a CANAL-TB-1-based CMS membrane at 500 and 600 °C with previously reported CMS membranes, according to one or more embodiments of the present invention.

[0017] Figure 12A-12B This is a graphical view showing a comparison of the separation performance of CMS-CANAL-TB-1 and CMS-Trip-TB-2 for (a) H2 / CO2 and (b) C2H4 / C2H6, according to one or more embodiments of the present invention.

[0018] Figure 13 This is a graphical view comparing the C2H4 / C2H6 separation performance of a Trip-TB-2-based CMS membrane heat-treated at 900°C with that of a previously reported CMS membrane, as shown in one or more embodiments of the present invention.

[0019] Figures 14A-14E These are graphical views of the separation performance of different CMS membranes according to one or more embodiments of the present invention: (a) CO2 / CH4, (b) H2 / CH4, (c) O2 / N2, (d) H2 / CO2 and (e) C2H4 / C2H6. Detailed Implementation

[0020] definition

[0021] As used herein, the term "intrinsically microporous polymer" refers to a polymer characterized by a BET surface area of ​​approximately 200 m², as determined by nitrogen adsorption at 77 K. 2 / g or larger of any polymer (e.g., polymer materials).

[0022] As used herein, the terms “oxygen-free” and / or “oxygen-free” refer to any material that contains no oxygen and / or, in some cases, only a small or negligible amount of oxygen. For example, intrinsically microporous oxygen-free ladder polymers may include intrinsically microporous ladder polymers having an oxygen-free chemical structure (e.g., repeating units). Materials that previously contained oxygen may be referred to as oxygen-free thereafter, provided that the material is oxygen-free when used to form carbon molecular sieve membranes (e.g., the material does not contain oxygen in its chemical structure at least prior to undergoing pyrolysis and / or heat treatment).

[0023] As used herein, the term "trapezoidal polymer" refers to any polymer having a backbone comprising fused rings.

[0024] As used herein, the term "pyrolysis product" refers to any substance and / or material obtained and / or produced by one or more of pyrolysis and heat treatment.

[0025] As used in this article, the term "CMS" refers to carbon molecular sieve membranes.

[0026] As used herein, the term "divalent" refers to any group having at least two connection sites; or being capable of combining with or being combined with at least two other groups. The term includes groups having two or more connection sites. For example, a trivalent group will be included in the meaning of the term "divalent" because a trivalent group has three connection sites, satisfying the requirement of having at least two connection sites.

[0027] As used herein, the term "alkyl" refers to a straight-chain or branched or cyclic hydrocarbon group or portion containing only carbon and hydrogen atoms, without unsaturation, and having 30 or fewer carbon atoms. The term "cycloalkyl" refers to an aliphatic cycloalkyl group having 3 to 10 carbon atoms in one or more rings, preferably 5 to 6 carbon atoms in a single ring. Alkyl groups can be monovalent (e.g., -CH3) or polyvalent (e.g., divalent, such as -CH2-CH2-), depending on the structure or chemical formula used. In some embodiments, the polyvalent group is a group having two or more carbon-carbon sigma bonds, such as -CH2- or methylene (i.e., divalent alkyl), while the terminal -CH3 (methyl) alkyl group has only one carbon-carbon sigma bond. Non-limiting examples of suitable alkyl groups include methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, isobutyl, sec-butyl, tert-butyl, cyclobutyl, pentyl, neopentyl, cyclopentyl, hexyl, cyclohexyl, 2-ethylhexyl, cyclohexylmethyl, heptyl, octyl, nonyl, decyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecanyl, octadecyl, nonadecanyl, cyclopentyl, cyclohexyl, etc. Other examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclopentenyl, cyclohexenyl, cyclohexadienyl, cyclohepttrienyl, norbornyl, norformyl, adamantyl, and spiro[4.5]decyl, as well as their homologues, isomers, etc. Preferably, the alkyl group is selected from methyl, ethyl, butyl, auxinyl, octadecyl, etc. The alkyl group may be substituted or unsubstituted. When this term is used with the modifier “substitution”, one or more hydrogen atoms have been independently substituted by any substituent disclosed herein. In some embodiments, the alkyl and / or cycloalkyl groups are oxygen-free or do not contain any oxygen atoms.

[0028] As used herein, the term "heteroalkyl" refers to an alkyl group as defined above that has at least one carbon atom substituted with a heteroatom. Heteroalkyl groups can be monovalent or polyvalent. Non-limiting examples of suitable heteroatoms include nitrogen, oxygen, and sulfur. Examples of cycloheteroalkyl groups particularly include morpholinyl, thiomorpholinyl, pyranyl, imidazolinyl, imidazolyl, oxazolyl, pyrazolyl, pyrazolyl, pyrrolyl, pyrrololinyl, tetrahydrofuranyl, tetrahydrothiophenyl, piperidinyl, piperazinyl, etc. Heteroalkyl groups can be substituted or unsubstituted. When the term is used with the modifier "substituted," one or more hydrogen atoms have been independently substituted by any substituent disclosed herein, or the substituent is bonded to a heteroatom, or both. In some embodiments, the heteroalkyl group is oxygen-free or does not contain any oxygen atoms (e.g., does not contain any oxygen heteroatoms).

[0029] As used herein, the term "alkenyl" refers to a straight-chain or branched hydrocarbon group or portion containing only carbon and hydrogen atoms and having at least one carbon-carbon double bond, which may be internal or terminal. Non-limiting examples of alkenyl groups include: —CH═CH2(vinyl), —CH═CHCH3, —CH═CHCH2CH3, —CH2CH═CH2(allyl), —CH2CH═CHCH3, —CH═CH—C6H5, —CH═CH—, —CH═C(CH3)CH2—, and —-CH═CHCH2— groups, —CH═CHF, —CH═CHCl, —CH═CHBr, etc. Examples of alkenyl groups include vinyl, propenyl, butenyl, pentenyl, hexenyl, butadienyl, pentadienyl, hexadienyl, etc. Alkenyl groups may be substituted or unsubstituted, monovalent or polyvalent. When the term is used with the modifier "substituted," one or more hydrogen atoms have been independently substituted by any substituent disclosed herein. In some embodiments, the alkenyl group is oxygen-free or does not contain any oxygen atoms.

[0030] As used herein, the term "aryl" refers to a monocyclic or polycyclic aromatic hydrocarbon group or portion containing only carbon and hydrogen atoms, wherein the carbon atoms form an aromatic ring structure. Aryl groups can be monovalent or polyvalent. If more than one ring is present, these rings can be fused, non-fused, or bridged. The term does not exclude the presence of one or more alkyl groups attached to the first aromatic ring or any additional aromatic ring present. The connection point can be an aromatic carbon atom in the ring structure or a carbon atom of an alkyl group attached to the ring structure. Non-limiting examples of aryl groups include phenyl (Ph), tolyl, xylyl, methylphenyl, (dimethyl)phenyl, —C6H4—CH2CH3 (ethylphenyl), naphthyl, and monovalent groups derived from biphenyl. Other examples of aryl groups having only an aromatic carbon ring include phenyl, 1-naphthyl (bicyclic), 2-naphthyl (bicyclic), anthraceneyl (tricyclic), phenanthrene (tricyclic), pentacyclic (pentacyclic), and other groups. Examples of polycyclic systems in which at least one aromatic carbide ring is fused with one or more cycloalkyl and / or heteroalkyl rings include cyclopentane (i.e., indenyl, which is a 5,6-bicycloalkyl / aromatic ring system), cyclohexane (i.e., imidazoline (i.e., benzimidazolyl, which is a 5,6-bicycloalkyl / aromatic ring system), and pyran (i.e., chromenyl, which is a 6,6-bicycloalkyl / aromatic ring system). Other examples of aryl groups include benzodioxane, benzodioxane, tryptophanyl, indolyl, etc. When the term is used with the modifier “substitution”, one or more hydrogen atoms have been independently substituted by any substituent disclosed herein. In some embodiments, the aryl group is oxygen-free or does not contain any oxygen atoms.

[0031] As used herein, the term "heteroaryl" refers to an aryl group in which at least one aromatic carbon atom in the ring structure is replaced by a heteroatom. Non-limiting examples of suitable heteroatoms include nitrogen, oxygen, and sulfur. The term does not exclude the presence of one or more alkyl groups attached to a first aromatic ring or any additional aromatic ring present. Heteroaryl groups can be monovalent or polyvalent. The connection point can be an aromatic carbon atom or an aromatic heteroatom in the aromatic ring structure or a carbon atom attached to an alkyl group of the aromatic ring. In some embodiments, the heteroaryl group is oxygen-free or does not contain any oxygen atoms (e.g., does not contain any oxygen heteroatoms).

[0032] As used herein, the term "heterocyclic" or "heterocyclic group" refers to a monocyclic and / or polycyclic group comprising one or more heteroatoms. Heterocyclic groups can be monovalent or polyvalent (e.g., tetravalent), aromatic or non-aromatic, substituted or unsubstituted. In some embodiments, the heterocyclic group is oxygen-free or does not contain any oxygen atoms. For example, in some embodiments, one or more heteroatoms do not contain any oxygen atoms.

[0033] As used herein, the term "polycyclic" or "polycyclic group" refers to a ring system comprising two or more cyclic groups that may be fused, bridged, or otherwise linked together. Polycyclic groups may be monovalent or polyvalent, aromatic or non-aromatic, substituted or unsubstituted. In some embodiments, the polycyclic group is oxygen-free or does not contain any oxygen atoms.

[0034] As used herein, the term "polyaryl" or "polyaryl group" refers to a group having two or more aryl groups that may be fused, bridged, or otherwise linked together. Polyaryl groups may be monovalent or polyvalent, substituted or unsubstituted. In some embodiments, the polyaryl group is oxygen-free or does not contain any oxygen atoms.

[0035] As used herein, the term "aliphatic" or "aliphatic group" refers to a saturated or unsaturated, straight or branched, cyclic (non-aromatic) or heterocyclic (non-aromatic) hydrocarbon or hydrocarbon group, each of which may be substituted or unsubstituted, and includes alkyl, alkenyl, and alkynyl groups, as well as alkanes, alkenes, and alkynes, including substituted or unsubstituted groups. Aliphatic groups can be monovalent (e.g., -CH3) or polyvalent (e.g., divalent (e.g., CH2-CH2-)), depending on the specific structure or formula used. A polyvalent group is a group having two or more carbon-carbon sigma bonds, rather than a group having only one carbon-carbon sigma bond. In the use of aliphatic groups, the number of H atoms present on one or more carbon atoms can be adjusted, thereby enabling suitable bonding schemes (e.g., in various cases, carbon may have 3, 2, or 1 H atom, thus allowing carbon to bond one, two, or three other atoms), and those skilled in the art can determine suitable bonding schemes. The term includes alicyclic groups having a cyclic structure, which can be monocyclic or polycyclic, substituted or unsubstituted. In some embodiments, the alicyclic group is oxygen-free or does not contain any oxygen atoms.

[0036] As used in this article, "halogen" or "halogen" refers to fluorine, chlorine, bromine, and iodine and their groups.

[0037] The term "substitution" refers to a molecule or functional group in which one or more hydrogen atoms of a specified atom have been replaced by other atoms or groups, provided that the valence of the specified atom is not exceeded. Each independently chosen substituent may be the same as or different from the other substituents. For example, the R group in a chemical formula may be independently replaced by halogen, hydroxyl, acyl, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, alkoxy, amino, amide, thiol, sulfone, sulfoxide, oxy, nitro, carbonyl, carboxyl, or amino acid (e.g., 1 to 4 times). For example, in "substituted alkyl," "substituted aryl," "substituted heteroaryl," etc., the term "substitution" means that the substituted group may contain groups such as alkyl, hydroxyl, amino, halogen, trifluoromethyl, cyano, -NH (alkyl), -N (alkyl)2, alkoxy, alkylthio, or carboxyl to replace one or more hydrogen atoms, as well as sulfur- and phosphorus-containing substitutions. The term "disubstituted" (e.g., in disubstituted aromatics) refers to a molecule or functional group in which two hydrogen atoms are substituted. In some embodiments, the substituents are oxygen-free or do not contain any oxygen atoms.

[0038] As used herein, the term "CANAL" refers to a polymer synthesis technique known as catalytic cyclization of aromatic norbornene monomers (CANAL), and also to a building block formed by the catalytic cyclization of two aromatic monomers with one norbornene monomer. The use of the term CANAL does not imply limitation of the aromatic portion to specific aromatic hydrocarbons, or the norbornene portion to norbornene, but rather includes the structures described herein and their derivatives, as described in this disclosure.

[0039] As used in this article, "trog base" ( "Base" refers to any Trüger base and / or any of its derivatives. The prototype of the base, 2,8-dimethyl-6H,12H-5,11-methylenedibenzo[b,f][1,5]diazo (CH3C6H4CH2)2CH2), is a tertiary amine that exhibits chirality due to the presence of two bridgehead steric nitrogen atoms. In some embodiments, relative to the phenyl ring... Alkali, Ger base derivatives may include more functional groups and / or substituents, or fewer functional groups and / or substituents. The functional groups and / or substituents may optionally be relative to... The base is provided at the same or different positions on the benzene ring.

[0040] As used in this article, “BET” refers to the Brunauer, Emmett, and Teller method for calculating the specific surface area of ​​a sample, including the pore size distribution of gas adsorption.

[0041] The gas permeation experiment was conducted in a constant volume / variable pressure device at approximately 35°C. The permeability of the pure gas was calculated using the following formula:

[0042]

[0043] Where P i It is the pure gas permeability, V d dp is the downstream volume, L is the membrane thickness, and dp is the downstream volume. i / dt represents the steady-state increase of pressure over time, P U Here, T is the upstream pressure, T is the temperature expressed in absolute units, R is the gas constant, and A is the active permeable area. Pure gas selectivity is calculated as the ratio of pure gas permeability:

[0044]

[0045] Ultra-high purity gases were used in the permeation and adsorption experiments, arranged in order of increasing condensability. An oxygen test was performed at the end of the series of experiments to prevent any chemisorption from occurring in the carbon molecular sieve membrane.

[0046] discuss

[0047] Polymer-derived carbon molecular sieves (CMS) are a class of amorphous inorganic membrane materials. Some CMS membranes can be prepared by controlled heat treatment of organic precursors under a substantially inert atmosphere—from approximately 500°C to approximately 1200°C. CMS membranes offer several advantages, including excellent chemical stability and the ability to withstand high pressures on condensable gases in energy-intensive separations. The sieving performance of CMS membranes can likely be attributed to their high micropore size and narrow pore size distribution. The numerous small micropores are often referred to as ultrapores. and even smaller submicropores This can provide a molecular sieving effect, enabling the differentiation of gas molecules that are very similar in size. For example, through a size selection mechanism, smaller oxygen molecules... It can be compared to nitrogen. It permeates through the CMS membrane more quickly, despite the small difference in kinetic diameter. Furthermore, the CMS membrane also contains a portion of larger, interconnected micropores. It provides a pathway with low diffusion barriers, resulting in high gas permeability. For example, see... Figure 1A-1B .

[0048] Certain polymers with intrinsic micropores have been considered for the preparation of carbon molecular sieve (CMS) membranes. A major challenge in these efforts is that CMS membranes prepared from intrinsically microporous polymers, while exhibiting acceptable gas permeability, possess unacceptably low to moderate gas pair selectivity. Furthermore, although some CMS membranes demonstrate suitable gas separation performance for the separation of gas molecules involving large differences in kinetic diameters (CO2 / CH4, H2 / CH4, and O2 / N2 separation), no CMS membrane has yet been achieved capable of separating gas molecules with very small differences in kinetic diameters (e.g., H2 / CO2, C2H4 / C2H6, and C3H6 / C3H8 separation), thus requiring further development to overcome the limitations of conventional polymer membrane materials. In other words, further development of materials with ultra-high particle size sieving capabilities remains crucial for advancing this technology in order to achieve the desired product purity (e.g., typically exceeding 99%) and provide high recovery rates.

[0049] This invention overcomes these and other challenges by providing improved CMS membranes based on novel polymer precursors. Unlike conventional materials, the CMS membranes disclosed herein are less fragile, easier to handle, and exhibit reproducible gas separation performance. These novel polymer precursors comprise ladder-shaped polymers with intrinsic micropores and an oxygen-free chemical structure. Using oxygen-free intrinsically microporous ladder-shaped polymers enables CMS membranes to possess unprecedented gas transport properties and exceptional gas separation performance. For example, unlike conventional materials, CMS membranes generated using intrinsically microporous oxygen-free ladder-shaped polymers exhibit unprecedentedly high gas permeability and high gas pair selectivity, making them optimal candidate membrane materials for gas separation processes, particularly the most energy-intensive and challenging gas separation applications, such as olefin / paraffin separation (e.g., C2H4 / C2H6, C3H6 / C3H8, etc.), H2 / CO2 separation, etc. Furthermore, using intrinsically microporous anaerobic aromatic ladder polymers as precursors allows for the formation of CMS structures with unique structures, enabling precise control over pore formation and demonstrating pore size truncation through narrow pore size distribution. By applying anaerobic precursors, pyrolysis byproducts such as CO and CO2 are eliminated during CMS structure formation, resulting in a unique CMS membrane with unprecedented gas separation performance.

[0050] Therefore, embodiments of this disclosure provide carbon molecular sieve membranes based on intrinsically microporous anaerobic ladder polymers. Intrinsically microporous anaerobic ladder polymers can be used as polymer precursors for preparing carbon molecular sieve membranes. For example, the carbon molecular sieve membranes of this disclosure can be formed using the pyrolysis and / or heat treatment of intrinsically microporous anaerobic ladder polymers. Therefore, in some embodiments, the carbon molecular sieve membrane comprises the pyrolysis product of the intrinsically microporous anaerobic ladder polymer. The pyrolysis product of the intrinsically microporous anaerobic ladder polymer may include any product (e.g., material or substance) obtained by the pyrolysis or heat treatment of the intrinsically microporous anaerobic ladder polymer (e.g., produced by pyrolysis or heat processing). For example, in some embodiments, the pyrolysis product of the intrinsically microporous anaerobic ladder polymer comprises the pyrolyzed intrinsically microporous anaerobic ladder polymer. In some embodiments, the pyrolysis product of the intrinsically microporous anaerobic ladder polymer comprises the heat-treated intrinsically microporous anaerobic ladder polymer.

[0051] Suitable intrinsically microporous anaerobic ladder polymers may include intrinsically microporous polymers and a backbone comprising fused rings. For example, in some embodiments, intrinsically microporous anaerobic ladder polymers include structural groups that restrict the rotational degrees of freedom and / or conformational flexibility of the intrinsically microporous anaerobic ladder polymer. For example, the structural groups may include sterically hindering deformation centers or deformation sites that restrict the polymer in this way. The structural groups may include rigid or kinked molecular structures that restrict rotation of the polymer backbone and / or prevent effective stacking of polymer chains. Examples of such structural groups include deformation sites, including but not limited to spirobisinden, spirodifluorene, ethanolanthracene, tetraphenylethylene, triphenylene, aromatic norbornene, etc. Bases and their derivatives. For example, in some embodiments, the intrinsically microporous anaerobic ladder polymer includes intrinsically microporous... Alkali-derived ladder polymers. In some embodiments, intrinsically microporous, oxygen-free ladder polymers include intrinsically microporous CANAL-derived aromatic norbornene ladder polymers. These should not be limiting, as other structural groups and / or deformation sites may be used without departing from the scope of this disclosure, provided that the structural groups have a chemical structure that does not include oxygen.

[0052] While not wishing to be bound by theory, it is believed that the size of the deformable sites included in the intrinsically microporous anaerobic ladder polymer and the anaerobic pyrolysis / thermal treatment schemes (e.g., pyrolysis temperature, pyrolysis atmosphere, soaking time, temperature rise rate, etc.) used to form carbon molecular sieve membranes (discussed in more detail below) provide different strategies, used alone or in combination, for fine-tuning various properties (e.g., pore size) of the resulting CMS membranes and / or optimizing their performance in specific gas separation applications. For example, this strategy can be used to design CMS membranes with enhanced gas selectivity and high gas permeability for high-energy-intensive gas separation, as well as other gas separation applications, such as those that are less energy-intensive or challenging. Examples of tunable properties include, but are not limited to, average pore size, pore size distribution, surface area (e.g., BET surface area), selectivity, permeability, etc.

[0053] In some embodiments, for example, the pore size of the carbon molecular sieve is related to the size of the deformation sites of the structural groups, and thus may affect the permeability of the resulting carbon molecular sieve membrane. For instance, compared to another carbon molecular sieve membrane prepared from an anaerobic ladder polymer with intrinsic micropores having smaller deformation sites, after heat treatment, the larger twisted sites in the anaerobic ladder polymer with intrinsic micropores can form a carbon molecular sieve membrane with a larger average pore size, thereby exhibiting higher permeability. Therefore, the permeability of the carbon molecular sieve membrane obtained after pyrolysis or heat treatment can be adjusted by modifying or selecting the anaerobic ladder polymer with intrinsic micropores, particularly the structural groups and / or deformation sites contained therein. This is one way to control pore formation using anaerobic ladder polymers with intrinsic micropores to obtain carbon molecular sieve membranes with narrow pore size distribution and clear pore size cutoff, thereby enhancing gas selectivity and high gas permeability for high-energy-intensive gas separation, etc.

[0054] Polymer precursors used to prepare carbon molecular sieve membranes may include any oxygen-free ladder-shaped polymer with intrinsic micropores. In some embodiments, the intrinsically microporous oxygen-free ladder-shaped polymer includes... Alkali-derived intrinsically microporous ladder polymers. For example, in some embodiments, the intrinsically microporous anaerobic ladder polymers comprise repeating units having a structure of formula (I):

[0055]

[0056] Wherein n is at least 1 (e.g., n can be in the range of 1 to about 1,000,000 or greater, or any incremental value or subrange between 1 and an upper limit range of 1,000,000 or greater), and where Q is an optionally substituted anaerobic tetravalent portion. In some embodiments, Q is an optionally substituted anaerobic tetravalent monocyclic or polycyclic portion. In some embodiments, Q is an optionally substituted anaerobic tetravalent portion selected from the following:

[0057]

[0058]

[0059] in:

[0060] R 1 R 2 R 3 and R 4 Each is independently selected from hydrogen, substituted or unsubstituted straight-chain or branched alkyl groups, substituted or unsubstituted aryl groups, substituted or unsubstituted heterocyclic groups, halogens, nitrile groups, trifluoromethyl groups, amino groups, and combinations thereof;

[0061] X is a divalent moiety selected from substituted and unsubstituted alkyl groups, substituted and unsubstituted alkenyl groups, substituted and unsubstituted aryl groups, substituted and unsubstituted polycyclic groups, and substituted and unsubstituted polyaryl groups; and

[0062] Y is a tetravalent moiety independently selected from substituted and unsubstituted aryl groups, substituted and unsubstituted heteroaryl groups, substituted and unsubstituted alicyclic groups, substituted and unsubstituted heterocyclic groups, substituted and unsubstituted polycyclic groups, and substituted and unsubstituted polyaryl groups.

[0063] In some embodiments, R 1 R 2 R 3 and R 4 One or more of them are the same. In some embodiments, R 1 R 2 R 3 and R 4 One or more of them are different.

[0064] Examples of the divalent part X in chemical formula (D) include, but are not limited to, the following:

[0065] —CH2—, —CH2CH2—, —CH=CH—,

[0066]

[0067] and / or

[0068] Examples of the tetravalent portion Y in chemical formula (D) include, but are not limited to:

[0069]

[0070] and / or

[0071]

[0072] in:

[0073] R a R b R c and R d Independently selected from hydrogen, halogens, substituted and unsubstituted alkyl groups, substituted and unsubstituted aliphatic groups, substituted and unsubstituted cycloalkyl groups, substituted and unsubstituted aryl groups, substituted and unsubstituted heterocyclic groups, groups having a -S- motif, groups having a -B< motif, groups having a -N< motif, groups having a -P< motif, groups having a -Si≡ motif, amino groups, and cyano groups. In some embodiments, R a R b R c and R d One or more of them are the same. In some embodiments, R a R b R c and R d One or more of them are different.

[0074] In some embodiments, the intrinsically microporous anaerobic ladder polymer comprises an intrinsically microporous ladder polymer of CANAL-derived aromatic norbornene. For example, in some embodiments, the intrinsically microporous anaerobic ladder polymer comprises repeating units having a structure of formula (II):

[0075]

[0076] Wherein n is at least 1 (e.g., n can be in the range of 1 to about 1,000,000 or greater, or any incremental value or subrange between 1 and an upper limit of 1,000,000 or higher), and where Z is an optionally substituted oxygen-free tetravalent moiety. In some embodiments, Z is an optionally substituted oxygen-free tetravalent monocyclic or polycyclic moiety. In some embodiments, Z includes one or more moiety Q as defined above in conjunction with chemical formula (II). In some embodiments, Z is a tetravalent phenyl group. For example, in some embodiments, the intrinsically microporous oxygen-free ladder polymer comprises repeating units having the structure of chemical formula (IIA):

[0077]

[0078] R 1 R 2 R 3 R 4 The definitions of R and n are as described above. In some embodiments, R 1 and R 2 They are the same. In some embodiments, R 3 and R 4 They are the same.

[0079] Non-limiting examples of specific oxygen-free ladder polymers with intrinsic micropores suitable for use as precursors in the preparation of carbon molecular sieve membranes include those provided below:

[0080]

[0081]

[0082]

[0083] In some embodiments, the average pore size of the carbon molecular sieve membrane ranges to approximately to approximately or and Any incremental value or subrange between these values. For example, in some embodiments, the average pore size of the carbon molecular sieve membrane is about 2.60 Å, about 2.65 Å, about 2.75 Å, about 2.89 Å, about 3.17 Å, about 3.20 Å, about 3.30 Å, about 3.40 Å, about 3.50 Å, about 3.73 Å, about 3.76 Å, about 3.46 Å, about 3.60 Å, about 3.80 Å, about 3.90 Å, about 3.96 Å, about 4.00 Å, about 4.30 Å, about 4.50 Å, about 5.50 Å, about 5.85 Å, about 5.90 Å, about 6.80 Å, about 7.50 Å, or about 8.50 Å.

[0084] In some embodiments, the pyrolysis products include intrinsically microporous, oxygen-free ladder polymers heat-treated at a pyrolysis temperature in the range of about 500°C to about 1200°C, or at any incremental pyrolysis temperature or subrange of temperature between 500°C and 1200°C (inclusive). For example, in some embodiments, the pyrolysis products include intrinsically microporous, oxygen-free ladder polymers pyrolyzed at 500°C, 550°C, 600°C, 650°C, 700°C, 750°C, and 800°C. Trapezoidal polymers, intrinsically microporous anaerobic trapezoidal polymers pyrolyzed at 850℃, 900℃, 950℃, 1000℃, 1050℃, 1100℃, and 1200℃, etc. These should not be limiting, as intrinsically microporous anaerobic trapezoidal polymers can be pyrolyzed at any temperature within the range of 500℃ to 1200℃ (inclusive).

[0085] In some embodiments, the intrinsically microporous anaerobic ladder polymer includes one or more of CANAL-TB-1, CANAL-TB-2, PIM-EA-TB, PIM-ET-TB-2, PIM-Trip-TB, PIM-Trip-TB-2, PIM-BTrip-TB, PIM-BTrip-TB-2, PIM-MP-TB, PIM-TMN-Trip-TB, PIM-SBI-TB, TB-Ad-Me, PIM-TB, CANAL-PIM, and their derivatives.

[0086] In some embodiments, the intrinsically microporous, oxygen-free ladder polymers disclosed herein are rigid, solution-processable polymers with a high Brunauer-Emmett-Teller (BET) surface area, for example, a BET surface area of ​​at least 200 m². 2 g -1 .

[0087] In some embodiments, the carbon molecular sieve membrane may be in the form of a membrane, thin film, hollow fiber, plate, or cylinder. These should not be limiting, as other geometries and forms are permitted without departing from the scope of the invention.

[0088] The embodiments of this disclosure further describe polymeric precursors for CMS membranes comprising intrinsically microporous anaerobic ladder polymers. Any intrinsically microporous anaerobic ladder polymer may be used in this invention without departing from its scope.

[0089] Figure 2 This is a flowchart of a pyrolysis scheme for preparing carbon molecular sieve membranes according to one or more embodiments of the present invention. Figure 2As shown, the pyrolysis scheme may include one or more of steps 202 to 206. In some embodiments, the method includes heating an intrinsically microporous anaerobic ladder polymer to a pyrolysis temperature (202) in an anaerobic atmosphere to optionally form a pyrolysis product without generating any oxygen-containing gas. In some embodiments, the pyrolysis scheme includes heating an intrinsically microporous anaerobic ladder polymer to a pyrolysis temperature (202) in an anaerobic pyrolysis atmosphere. The intrinsically microporous anaerobic ladder polymer may include any intrinsically microporous anaerobic ladder polymer disclosed herein. In some embodiments, one or more of repeating units X and Y having the structure of formula (I), and / or Z having the structure of formula (II), may be selected or varied to control, modify, or adjust the pore size, pore formation, etc., of the pyrolysis product and / or the resulting carbon molecular sieve. For example, in some embodiments, the pore size of the CMS membrane and / or the pyrolysis product increases with increasing volume of the X, Y, and Z groups (e.g., type and number of substituents, degree of branching, number of fused rings, etc.).

[0090] Heating can be achieved at approximately 1°C / s -1 Approximately 1℃h -1 Or at any rate of temperature rise (e.g., heating rate) between them. For example, in some embodiments, at 1°C / min. -1 and 5℃min -1 Between (e.g., about 3°C / min) -1 Heating is performed at a rate of temperature increase, at least until the pyrolysis temperature is reached. The pyrolysis temperature can be in the range of about 500°C to about 1200°C, or any incremental temperature or sub-range between 500°C and 1200°C. For example, in some embodiments, the pyrolysis temperature is about 500°C to about 900°C, such as about 500°C, about 600°C, about 700°C, about 800°C, or about 900°C. Heating can be performed in a furnace (e.g., a tube furnace), an oven, or any other suitable heating device. In one embodiment, a Carbolite three-zone tube furnace is used.

[0091] As described above, heating can be carried out in a pyrolysis atmosphere, which may be selected as oxygen-free. For example, in some embodiments, heating is carried out in an oxygen-free pyrolysis atmosphere. An oxygen-free pyrolysis atmosphere may include one or more additional inert substances, such as nitrogen, helium, argon, hydrogen, etc., provided that O2 is absent or present only in negligible or trace amounts. In one embodiment, for example, at approximately 1000 cm⁻¹… 3 (STP)min -1Heating is performed under an inert nitrogen gas flow rate. Upon reaching the pyrolysis temperature, the intrinsically microporous, oxygen-free ladder polymer can be isothermally maintained at the pyrolysis temperature for a predetermined duration. The duration is not particularly limited and can range from about 1 second to about 24 hours. In some embodiments, the duration is between 50 and 70 minutes, for example, about 60 minutes. In some embodiments, the step of maintaining the temperature at the pyrolysis temperature can be referred to as isothermal immersion.

[0092] In some embodiments, the intrinsically microporous anaerobic ladder polymer is optionally heated in an anaerobic pyrolysis atmosphere without (e.g., without involving) any conventional combustion reactions. For example, in some embodiments, heating the intrinsically microporous anaerobic ladder polymer eliminates the generation (e.g., release) of oxygen-containing products such as carbon monoxide, carbon dioxide, and other oxygen-containing products (e.g., byproducts). In this way, the method minimizes complications of the pyrolysis process, providing a less hazardous and more controllable process for preparing carbon molecular sieve membranes with excellent gas separation performance, including high permeability and high gas pair selectivity. In some embodiments, no oxygen-containing compounds are precipitated and / or generated during heating of the intrinsically microporous anaerobic ladder polymer to the pyrolysis temperature.

[0093] After exposing the intrinsically microporous anaerobic ladder polymer to the pyrolysis temperature for a predetermined duration (204), the formed material can be cooled (206) to a second temperature. In some embodiments, for example, the material is removed from the heating device, or the heating device is turned off, and the material is allowed to cool to approximately room temperature (e.g., about 25°C, or any temperature between about 20°C and 30°C) and / or a duration including about 600 minutes or less is selected. In some embodiments, the material remaining after isothermal immersion comprises, or is referred to as, the pyrolysis product of the intrinsically microporous anaerobic ladder polymer. In some embodiments, the material remaining after isothermal immersion and after allowing the material to cool to approximately room temperature comprises, or is referred to as, the pyrolysis product of the intrinsically microporous anaerobic ladder polymer. In other words, heating alone or heating combined with cooling can form the pyrolysis product of the intrinsically microporous anaerobic ladder polymer, and thus form a carbon molecular sieve membrane.

[0094] In some embodiments, one or more parameters may be adjusted to adjust one or more properties of the carbon molecular sieve membrane. These properties may include, but are not limited to, one or more of pore size, pore size distribution (e.g., more uniform or less uniform pore size distribution and / or pore size), pore formation, membrane structure, channel structure, membrane thickness, selectivity, permeability, surface area (e.g., BET surface area), wherein adjustments to these and one or more of these and other properties can be used for the separation of a specific gas. In some embodiments, method 200 includes adjusting one or more of X and Y in repeating units having a structure of chemical formula (I) to adjust one or more properties of the carbon molecular sieve membrane. In some embodiments, method 200 further includes adjusting Z in repeating units having a structure of chemical formula (II) to adjust one or more properties of the carbon molecular sieve membrane. In some embodiments, method 200 further includes adjusting the pyrolysis temperature to adjust one or more properties of the carbon molecular sieve membrane. In some embodiments, method 200 further includes adjusting the pyrolysis atmosphere (e.g., a chemical substance present in the pyrolysis atmosphere, such as an inert substance) to adjust one or more properties of the carbon molecular sieve membrane. In some embodiments, method 200 further includes adjusting the rate of temperature rise (e.g., heating rate) to adjust one or more properties of the carbon molecular sieve membrane. In some embodiments, method 200 further includes adjusting isothermal immersion (e.g., the duration of holding a polymer precursor at a selected temperature or within a selected temperature range) to adjust one or more properties of the carbon molecular sieve membrane.

[0095] In some embodiments, for example, the pyrolysis process can be used to adjust the spacing or distance between polymer chains (e.g., pore size). In some embodiments, the pyrolysis process can be used to minimize the wide pore size distribution of the pyrolysis products to obtain a carbon molecular sieve membrane with a clear pore size cutoff. For example, carbon molecular sieve membranes with very narrow and / or clear pore size distributions can be achieved to achieve unprecedented gas separation performance in energy-intensive separations, including but not limited to H2 / CO2 separation, ethylene / ethane separation, propylene / propane separation, etc.

[0096] Figure 3 This is a flowchart of a gas separation method according to one or more embodiments of the present invention. Figure 3As shown, the method may include one or more of the following steps: contacting a carbon molecular sieve membrane with a fluid comprising one or more gaseous components (302), and separating at least one gaseous component from the fluid (304). The contact may be performed by one or more of feeding, flowing, passing through, injecting, and / or introducing the fluid into the carbon molecular sieve membrane. The separation may include separating at least one gaseous component from the whole or from a specific chemical species or chemical component. In some embodiments, the separation may result in the production of a permeate having a reduced concentration of at least one substance and a permeate having an increased concentration of that substance. For example, in some embodiments, at least one of the gaseous components permeates through the carbon molecular sieve membrane.

[0097] Carbon molecular sieve membranes can be used for a variety of separations. As described above, for example, in some embodiments, carbon molecular sieve membranes are used for energy-intensive and / or challenging gas separation applications, including but not limited to ethylene and ethane, propylene and propane, CO2 and H2, etc. At least one advantage of the carbon molecular sieve membranes disclosed herein is that they can be used in the most energy-intensive and challenging gas separation applications. For example, gas separation applications involving gas components or gas molecules with narrow kinetic diameter differences typically have high energy requirements and therefore correspondingly high operating costs. The narrow pore size distribution and / or clear pore size cutoff of the carbon molecular sieve membranes disclosed herein impart high selectivity for gas pairs with narrow kinetic diameter differences.

[0098] Carbon molecular sieve membranes can be used in gas separation applications involving gas molecules with small differences in kinetic diameter. For example, in some embodiments, carbon molecular sieve membranes can be used in gas separation applications where the difference in kinetic diameter of the gas molecules to be separated is less than or approximately [missing information]. Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about Less than or about or and Any incremental value or subrange between.

[0099] Carbon molecular sieve membranes can be used in other types of applications. For example, in some embodiments, carbon molecular sieve membranes can be used for, but are not limited to, separating oxygen and / or nitrogen from air, capturing CO2 from flue gas, propane / propylene separation, hydrogen purification, recovering hydrogen from refinery fuel gas and exhaust gas, methane enrichment, removing acid gases from natural gas, dehydration processes, etc. In some embodiments, carbon molecular sieve membranes are used to separate specific gases, including but not limited to one or more of H2 and CO2, C2H4 and C2H6, C3H6 and C3H8, CO2 and CH4, H2S and CH4, CO2 and H2S and CH4, CO2 and N2, O2 and N2, N2 and CH4, He and CH4, H2 and CH4, H2 and C2H4, ethylene and ethane, propylene and propane, ethylene / propylene and ethane / propane, etc. In some embodiments, the fluid includes one or more of biogas, natural gas, refinery tail gas, etc. In some embodiments, the fluid includes one or more of H2, He, CH4, NH3, H2O, Ne, N2, CO, NO, O2, H2S, HCl, Ar, CO2, N2O, and SO2.

[0100] Example

[0101] Examples demonstrate enhanced performance of carbon molecular sieve membranes prepared from polymer precursors of oxygen-free ladder polymers with intrinsic micropores. As demonstrated herein, the desired pore size of CMS membranes can be fine-tuned by changing or adjusting one or more of the following: (a) the size of the deformation sites in the polymer precursor and (b) parameters of the pyrolysis scheme, including but not limited to pyrolysis temperature, pyrolysis atmosphere, heating rate or temperature rise rate, and / or immersion time (e.g., isothermal immersion time). This strategy can be used to design ladder polymers with optimized intrinsic micropores to produce CMS membranes with desired pore size and / or pore size distribution to enhance gas pair selectivity and high permeability. Four precursors with different deformation sites, namely CANAL-TB-1, PIM-ET-TB-2, PIM-Trip-TB-2, and PIM-BTrip-TB-2, were evaluated to assess the effect of systematically altering the deformation sites on the structure and gas separation performance of the CMS membranes. Preliminary gas transport results for CMS membranes, including those based on CANAL-TB-1 and Trip-TB-2, demonstrate unprecedented performance in H2 / CO2 and C2H4 / C2H6 separation, respectively.

[0102] Example 1

[0103] General pyrolysis schemes for forming CMS films

[0104] The performance of CMS membranes depends entirely on their pore size, size distribution, and interconnectivity, although complete control and design of these three structural properties remain limited. In the CMS membrane preparation disclosed herein, the pyrolysis scheme and polymer precursor type are considered to be two major factors affecting the separation performance of CMS membranes. Figure 4 For example, pyrolysis schemes may include, but are not limited to, pyrolysis temperature (T). p The effects of the choice of polymer precursor on the structure and properties of CMS membranes have not been investigated in any relevant polymer series for any system, especially intrinsically microporous polymers. Therefore, this is at least part of the focus of this example.

[0105] More specifically, the effects of the pyrolysis scheme and the deformation sites of the anaerobic ladder polymer of the intrinsic microporous precursor on the CMS membrane properties were evaluated. The conclusions include: (1) the use of an anaerobic aromatic PIM-based precursor results in a unique CMS structure with more controllable pore formation. At least one advantage of using an anaerobic precursor is the elimination of conventional combustion reactions (e.g., the release of CO and CO2), thereby minimizing the complexity of the pyrolysis process. Figures 5A-5B This is the first process report on the near elimination of oxygen (internal = polymer structure, external = pyrolysis atmosphere) during pyrolysis events. Another conclusion includes (2) that larger deformation sites in the original polymer result in a larger average pore size in the CMS film. Figures 6A-6D ).

[0106] Generally, to prepare CMS membranes, a polymer precursor, including an oxygen-free ladder polymer containing intrinsic micropores, is placed in a Carbolite three-zone tube furnace, providing a 1000 cm⁻¹ pressure. 3 (STP)min -1 N2 ( Figure 7 Temperature was measured using a thermocouple close to the sample. Oxygen concentration in the furnace was measured using a Cambridge Sensotec Rapidox 3100 O2 analyzer, and was not exceeded 2 ppm. The polymer precursor was fed at 3 °C / min. -1 The temperature is increased at a rate of rise to a set temperature (e.g., pyrolysis temperature) between 500 and 900°C, and then held isothermally at the set temperature for approximately 60 minutes. Figure 8 After isothermal soaking, allow the furnace to be passively cooled to approximately room temperature (e.g., approximately 25°C). Figure 9 After being removed from the furnace and cooled to room temperature, the gas permeability of the membrane was tested immediately.

[0107] Example 2

[0108] Separation performance of CMS membrane based on CANAL-TB-1

[0109]

[0110] Permeability and selectivity measurements were performed on pristine and CANAL-TB-1-based CMS membranes subjected to heat treatment at different pyrolysis temperatures. Table 1 reports the pure gas permeability and selectivity for ideal gas pairs of the CANAL-TB-1-based carbon membranes. Pristine CANAL-TB-1 exhibited the highest permeability for all gases but the lowest selectivity—this is due to the broad pore size distribution in the pristine, unpyrolyzed polymer. The 500°C-based CANAL-TB-1 CMS membrane showed a sharp decrease in permeability but a significant increase in selectivity. The decrease in permeability is likely due to the deformation sites of two main-chain bridges (e.g., norbornene and...). Loss of alkali. Based on 600℃ and 700℃ CMS membranes from CANAL-TB-1, high methane rejection rates were observed. This indicates an extreme shift in pore size distribution towards smaller pores, resulting in extremely high selectivity for H2 / CH4 and CO2 / CH4. At higher pyrolysis temperatures of 800–900 °C, the pore size continues to decrease, clearly demonstrated by the significant decrease in CO2 permeability and the increase in selectivity.

[0111] Figure 10A The relationship between the gas separation performance of the CMS membrane prepared by CANAL-TB-1 and the pyrolysis temperature is shown, and in Figure 10B A comparison was made between traditional and state-of-the-art CMS membranes. Specifically, Figure 10A This is a graphical view illustrating the H2 / CO2 separation performance of the heat-treated derivatives of the original CANAL-TB-1 and CANAL-TB-2 according to one or more embodiments of the present invention. Figure 10B This is a graphical view illustrating a comparison of the H2 / CO2 performance of a previously reported conventional CMS membrane with that of the CANAL-TB-1 membrane of this disclosure, prepared by pyrolysis at temperatures ranging from 800°C to 900°C, according to one or more embodiments of the present invention. The CANAL-TB-1-based CMS membrane exhibits unprecedented performance in H2 / CO2 separation, significantly exceeding that of conventional membranes. Figure 10A The upper limit of polymers shown in 2008 is better than, for example, Figure 10B Any other reported CMS membrane shown makes the CANAL-TB1-based CMS membrane the best performing membrane in the art for H2 / CO2 separation.

[0112] A CANAL-TB-1-based CMS membrane, heat-treated at 500°C and 600°C, was used to test the more challenging C2H4 / C2H6 separation. For example... Figure 11 As shown, the performance of the CANAL-TB-1 derived CMS film is similar to that of previously reported CMS films; in fact, the properties of the CMS film based on CANAL-TB-1 at 600°C overlap with the properties of the PIM-1 CMS film based on heat treatment at 800°C.

[0113] Table 1: Gas permeability and selectivity of pristine and heat-treated CANAL-TB-1 membranes

[0114]

[0115] a 1 Barrer = 10 -10 cm 3 (STP)cm cm -2 s -1 cmHg -1 or 7.6×10 -18 m 3 (STP)mm -2 s -1 Pa -1 .

[0116] The measurements were taken at a temperature of 35°C; the upstream pressure was 2 atmospheres.

[0117] b Measurements were taken at an upstream pressure of 10 atm.

[0118] Example 3

[0119] Separation performance of CMS membranes based on Trip-TB-2

[0120]

[0121] As mentioned above, the pore size in carbon membranes is considered to be closely related to the size of the deformation sites in the original polymer (e.g., the polymer precursor before pyrolysis). It is believed that original polymers with intrinsic micropores possessing larger deformation sites can form CMS membranes with larger pore sizes, thus exhibiting higher gas permeability. In this regard, the Trip-TB-2-based carbon membranes showed significantly higher permeability for all gases compared to the CANAL-TB-1-based CMS membranes (Table 1) (Table 2). Similarly, the permeability of the Trip-TB-2-based CMS membranes for all gases decreased significantly with increasing pyrolysis temperature. In terms of selectivity, all gas pairs except H2 / CO2 showed a significant increase. In particular, compared to the ultra-high selectivity of the CANAL-TB-1-based CMS membranes, Figure 12AThe Trip-TB-2-based CMS membrane was shown to have no H2 / CO2 selectivity. However, Figure 12B The unprecedented C2H4 / C2H6 performance of the Trip-TB-2-based carbon film was demonstrated under pure gas and mixed gas conditions.

[0122] Table 2: Permeability and selectivity of pristine and heat-treated Trip-TB-2 membranes

[0123]

[0124] a 1 Barrer = 10 -10 cm 3 (STP)cm cm -2 s -1 cm Hg -1 or 7.6×10 -18 m 3 (STP)mm -2 s -1 Pa -1 .

[0125] The measurements were taken at a temperature of 35°C; the upstream pressure was 2 atmospheres.

[0126] like Figure 13 As shown, when the total feed pressure of the 1:1 feed mixture increased from 10 bar to 20 bar, the C2H4 mixed gas permeability and C2H4 / C2H6 selectivity of the CMS membrane based on 900°C-Trip-TB-2 decreased slightly, but the performance was still far superior to carbon membranes currently reported in the art. Figure 13 In this study, the performance of PIM-Trip-TB-2 derived CMS membranes for ethylene / ethane separation after pyrolysis at 900 °C was compared with previously reported polymer and CMS membranes. Figure 13 As shown, the membrane prepared according to this disclosure exhibits performance far superior to any other membrane type previously reported. This result demonstrates unprecedented performance of Trip-TB-2-based CMS membranes for C2H4 / C2H6 separation.

[0127] Example 4

[0128] Separation performance of conventional CMS membranes

[0129] For comparison, Figures 14A-14EThe figures illustrate the separation performance of conventional or previously reported CMS membranes for many gas pairs, including CO2 / CH4, H2 / CH4, O2 / N2, H2 / CO2, C2H4 / C2H6, and C3H6 / C3H8. It is clear from these figures that conventional CMS membranes used for these gas pairs, including for more challenging gas separation applications, still require further improvement to overcome the limitations of conventional state-of-the-art polymer membrane materials. As shown, further development of conventional materials is needed to achieve the desired product purity (typically greater than 99%) and provide high recovery rates.

Claims

1. A carbon molecular sieve membrane comprising: The pyrolysis products of intrinsically microporous oxygen-free ladder polymers; wherein: (a) The intrinsically microporous, oxygen-free ladder polymer comprises repeating units having the following chemical formula (I): in: Q is the substituted or unsubstituted tetravalent anaerobic moiety; and n is at least 1; or The intrinsically microporous oxygen-free ladder polymer comprises repeating units having the following chemical formula (II): in: Z is the substituted or unsubstituted non-oxygen tetravalent moiety; and n is at least 1; (b) The pyrolysis products are formed without producing oxygen-containing compounds; (c) The pyrolysis is carried out at a pyrolysis temperature of 500°C to 1200°C.

2. The carbon molecular sieve membrane according to claim 1, wherein Q is selected from: in: R 1 R 2 R 3 and R 4 The group is independently selected from hydrogen, substituted or unsubstituted straight-chain or branched alkyl groups, substituted or unsubstituted aryl groups, substituted or unsubstituted heterocyclic groups, halogens, nitrile groups, trifluoromethyl groups, and combinations thereof; X is a divalent moiety selected from substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted aryl, substituted or unsubstituted polycyclic, and substituted or unsubstituted polyaryl; and Y is independently selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alicyclic, substituted or unsubstituted heterocyclic, substituted or unsubstituted polycyclic, and the tetravalent part of substituted or unsubstituted polyaryl.

3. The carbon molecular sieve membrane according to claim 2, wherein X is selected from: —CH2—, —CH2CH2—, —CH=CH—, ， ， and .

4. The carbon molecular sieve membrane according to claim 2, wherein Y is independently selected from: in: R a R b R c and R d Independently selected from hydrogen, halogen, substituted or unsubstituted alkyl, substituted or unsubstituted aliphatic group, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heterocyclic group, group having -S- motif, group having -B< motif, group having -N< motif, group having -P< motif, group having -Si≡ motif, amino and cyano.

5. The carbon molecular sieve membrane according to any one of claims 1-4, wherein the intrinsically microporous anaerobic ladder polymer comprises repeating units having a structure of chemical formula (I), and the intrinsically microporous anaerobic ladder polymer comprises repeating units having one of the following structures: Each R and R' is independently selected from H, Me, F, Cl, Br, substituted or unsubstituted straight-chain alkyl and substituted or unsubstituted branched alkyl.

6. The carbon molecular sieve membrane according to claim 1, wherein the intrinsically microporous anaerobic ladder polymer comprises repeating units having a structure of chemical formula (II), and the intrinsically microporous anaerobic ladder polymer comprises repeating units having the following structure: Each R and R' is independently selected from H, Me, F, Cl, Br, substituted or unsubstituted straight-chain alkyl and substituted or unsubstituted branched alkyl.

7. A gas separation method, comprising: A fluid comprising multiple gaseous components is brought into contact with the carbon molecular sieve membrane of claim 1; as well as At least one of the gaseous components is separated from the fluid.

8. The gas separation method according to claim 7, wherein the difference in the kinetic diameter of the separated gas components is 0.20 angstroms or less.

9. The gas separation method according to claim 7, wherein the plurality of gas components includes at least C2H4 and C2H6.

10. The gas separation method according to claim 7, wherein the plurality of gas components includes at least C3H6 and C3H8.

11. The gas separation method according to claim 7, wherein the plurality of gas components includes at least H2 and CO2.

12. The gas separation method according to any one of claims 7-11, wherein the plurality of gas components includes a plurality of C2H4, C2H6, C3H6, C3H8, H2, CO2, CH4, N2, O2, He, NH3, H2O, Ne, CO, NO, H2S, HCl, Ar, N2O and SO2.

13. A method for preparing a carbon molecular sieve membrane according to claim 1, the method comprising: The intrinsically microporous oxygen-free ladder polymer is heated to the pyrolysis temperature in an oxygen-free pyrolysis atmosphere to form pyrolysis products.

14. The method according to claim 13, wherein the pyrolysis temperature is between 500°C and 1200°C.

15. The method according to claim 13 or 14, wherein no oxygen-containing compounds are generated during heating of the intrinsically microporous oxygen-free ladder polymer to the pyrolysis temperature.

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