Carbon molecular sieve monoliths and methods for making the same

Abstract

Method for forming a carbon molecular sieve monolith include loading a resin into an extruder, heating the resin to form a polymer melt, introducing the polymer melt into a microcapillary film die to form microcapillaries in the polymer melt, quenching the polymer melt to form a microcapillary film, creating layers of microcapillary films, laminating the layers, or placing the layers of microcapillary films into a mold, heating the layers of microcapillary films to a temperature of from 50°C to 350°C to form a polymer monolith, pyrolizing the polymer monolith by heating the polymer monolith to a temperature of from 500°C to 1700°C to form the carbon molecular sieve monolith; and activating the carbon molecular sieve monolith using one or more oxidants.

Description

85371-WO-PCT / DOW 85371 WO CARBONMOLECULARSIEVEMONOLITHS ANDMETHODS FORMAKING THESAMECROSS-REFERENCETORELATEDAPPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 592,792 filed October 24, 2023, the contents of which are incorporated in their entirety herein. BACKGROUND Field

[0002] The present specification generally relates to carbon molecular sieve monoliths for gas separation. In particular, the present specification relates to carbon molecular sieve monoliths for gas separation and methods for making carbon molecular sieve monoliths for gas separation. Technical Background

[0003] Carbon molecular sieves and carbon molecular sieve membranes have been used to separate gases. Carbon molecular sieves may be prepared from a variety of resins that are pyrolyzed at various temperatures and / or under various conditions. The pyrolysis reduces the resins to carbon, but maintains at least some porosity in the pyrolyzed product, in the form of micropores. The carbon molecular sieves thus formed may then be employed in conventional gas separations equipment employing adsorption of particular gases, such as packed beds, columns, and the like, where the micropore size determines which gas in a gas mixture is adsorbed and which is not. Adsorption and desorption techniques may be alternated to carry out the separation, according to, for example, conventional pressure swing adsorption (PSA) or temperature swing adsorption (TSA) methods.

[0004] Structured adsorbents can reduce the adsorbent bed size and capital cost of PSA using shorter cycle operations without causing pressure drop and mass transfer issues.

[0005] Accordingly, a need exists for structure adsorbents and methods for making structured adsorbents for gas separation.85371-WO-PCT / DOW 85371 WO SUMMARY

[0006] According to one embodiment, a method for forming a carbon molecular sieve monolith, includes loading a resin into an extruder, heating the resin to form a polymer melt, introducing the polymer melt into a microcapillary film die to form microcapillaries in the polymer melt, quenching the polymer melt to form a microcapillary film, creating layers of microcapillary films, laminating the layers of microcapillary films or placing the layers of microcapillary films into a mold, heating the layers of microcapillary films to a temperature of from 50 °C to 350 °C to form a polymer monolith, pyrolizing the polymer monolith by heating the polymer monolith to a temperature of from 500 °C to 1700 °C to form the carbon molecular sieve monolith; and activating the carbon molecular sieve monolith using one or more oxidants.

[0007] In another embodiment, a carbon molecular sieve monolith includes a first end and a second end opposite the first end, two or more sheets of carbon microcapillary films aligned in parallel such that first axial ends of the two or more sheets of carbon microcapillary films are positioned at the first end of the carbon molecular sieve monolith and second axial ends of the one or more sheets of carbon microcapillary films are aligned at the second end of the carbon molecular sieve monolith, and microcapillaries extending from the first end of the one or more sheets of carbon microcapillary films to the second end of the one or more sheets of carbon microcapillary films, wherein outer surfaces of the one or more sheets of carbon microcapillary films are joined together to form the carbon molecular sieve monolith, and the carbon molecular sieve monolith has a cell density of greater than or equal to 300 cells per square inch.

[0008] Additional features and advantages will be set forth in the detailed description that follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments described herein, including the detailed description that follows, the claims, as well as the appended drawings.

[0009] It is to be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments, and are incorporated into and constitute a part of this specification. The drawings85371-WO-PCT / DOW 85371 WO illustrate the various embodiments described herein, and together with the description serve to explain the principles and operations of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG. 1 is a schematic of a carbon molecular sieve monolith according to embodiments disclosed and described herein.

[0011] FIG. 2 is a magnified photograph of a cross section of a carbon molecular sieve monolith according to embodiments disclosed and described herein.

[0012] FIG. 3 is a magnified photograph of a cross section of a carbon molecular sieve monolith according to embodiments disclosed and described herein.

[0013] FIG. 4 is a graph of the capacity at various pressures on various dates of a carbon molecular sieve monolith according to embodiments disclosed and described herein.

[0014] FIG. 5 is a graph of the capacity at various pressures on various dates of a carbon molecular sieve monolith according to embodiments disclosed and described herein.

[0015] FIG. 6 is a graph of the capacity at various pressures of the carbon molecular sieve monolith and pellets according to embodiments disclosed and described herein. DETAILED DESCRIPTION

[0016] Reference will now be made in detail to embodiments of carbon molecular sieve monoliths and methods for making carbon molecular sieve monoliths. In one embodiment, a method for forming a carbon molecular sieve monolith includes loading a resin into an extruder, heating the resin to form a polymer melt, introducing the polymer melt into a microcapillary film die to form microcapillaries in the polymer melt, quenching the polymer melt to form a microcapillary film, creating layers of microcapillary films, laminating the layers, or placing the layers of microcapillary films into a mold, heating the layers of microcapillary films to a temperature of from 50 °C to 350 °C to form a polymer monolith, pyrolizing the polymer monolith by heating the polymer monolith to a temperature of from 500 °C to 1700 °C to form the carbon85371-WO-PCT / DOW 85371 WO molecular sieve monolith; and activating the carbon molecular sieve monolith using one or more oxidants.

[0017] In another embodiment, a carbon molecular sieve monolith includes a first end and a second end opposite the first end, two or more sheets of carbon microcapillary films aligned in parallel such that first axial ends of the two or more sheets of carbon microcapillary films are positioned at the first end of the carbon molecular sieve monolith and second axial ends of the one or more sheets of carbon microcapillary films are aligned at the second end of the carbon molecular sieve monolith, and microcapillaries extending from the first end of the one or more sheets of carbon microcapillary films to the second end of the one or more sheets of carbon microcapillary films, wherein outer surfaces of the one or more sheets of carbon microcapillary films are joined together to form the carbon molecular sieve monolith, and the carbon molecular sieve monolith has a cell density of greater than or equal to 300 cells per square inch. Carbon molecular sieve monoliths according to embodiments will now be described with reference to the appended drawings.

[0018] With reference now to FIG. 1, carbon molecular sieve monoliths 100 according to embodiments includes a first end 110 and a second end 120 opposite the first end 110. The carbon molecular sieve monolith includes two or more sheets of carbon microcapillary films 210 and 220. For example, the carbon molecular sieve monolith may include a first sheet 210 and a second sheet 220. The first sheet 210 and the second sheet 220 are aligned in parallel such that first axial end 213 of the first sheet 210 and the first axial end 223 of the second sheet 220 are positioned at the first end 110 of the carbon molecular sieve monolith 100 and second axial end 217 of the first sheet 110 and the second axial end 227 of the second sheet 220 are aligned at the second end 120 of the carbon molecular sieve monolith 100. The carbon molecular sieve monolith 100 includes microcapillaries 300 extending from the first end 110 to the second end 120. The outer surface 215 of the first sheet 210 and the outer surface 225 of the second sheet 220 are joined together to form the carbon molecular sieve monolith 100. It should be understood that not all microcapillaries 300 of the of the carbon molecular sieve monolith 100 are labelled in FIG. 1.

[0019] As shown in the embodiments depicted in FIG. 1, the carbon molecular sieve monolith 100 is formed by having the outer surfaces 215 and 225 of sheets 210 and 220 joined together to form the carbon molecular sieve monolith 100. Methods for joining the outer surfaces 215 and85371-WO-PCT / DOW 85371 WOin more detail herein.

[0020] As shown in the embodiments depicted in FIG. 1, outer surfaces 215 and 225 of sheets 210 and 220 are in physical contact, and by forming carbon molecular sieve monolith 100 according to embodiments disclosed and described herein, the outer surfaces 215 and 225 are joined together. According to embodiments, the outer surfaces 215 and 225 are in physical contact and are joined together, such as by fusing, such that the outer surfaces 215 and 225 that are in physical contact are joined and form an interface that does not allow gas to bypass the microcapillary channels. In this way, the individual sheets 210 and 220 are joined together to form the carbon molecular sieve monolith. By joining the individual sheets 210 and 220 as disclosed and described herein, the carbon molecular sieve monolith 100 of embodiments is easily transportable and maintains its shape and integrity during use.

[0021] In embodiments, the carbon molecular sieve monolith 100 includes 10 or more sheets of carbon microcapillary film. In embodiments, the carbon molecular sieve monolith 100 includes 5 or more sheets of carbon microcapillary film, 10 or more sheets of carbon microcapillary film, 50 or more sheets of carbon microcapillary film, 100 or more sheets of carbon microcapillary film, 200 or more sheets of carbon microcapillary film, or 500 or more sheets of carbon microcapillary film. In embodiments, the carbon molecular sieve monolith 100 includes from 2 to 5000, from 2 to 1000, or from 2 to 500 sheets of carbon microcapillary film.

[0022] In embodiments, the carbon molecular sieve monolith 100 may have a height of from 0.5 mm to 1.5 m, wherein the height is measured perpendicular to the edge of the layers of microcapillary films. In embodiments, the carbon molecular sieve monolith 100 may have a height of from 0.5 mm to 1.5 m, from 1 mm to 1 m, or from 5 mm to 0.5 m, wherein the height is measured perpendicular to the edge of the layers of microcapillary films.

[0023] In embodiments, the adsorbent loading in the carbon molecular sieve monolith is at least 0.1 g / cm3. As used herein, “adsorbent loading” refers to the amount of adsorbent per unit volume of monolith. For example, a carbon molecular sieve monolith according to embodiments herein with an adsorbent loading of 0.1 g / cm3would have 0.1 g of the adsorbent solid per cubic centimeter of the carbon molecular sieve monolith. In embodiments, the adsorbent loading in the85371-WO-PCT / DOW 85371 WO carbon molecular sieve monolith is at least 0.1 g / cm3, at least 0.2 g / cm3, at least 0.3 g / cm3, or at least 0.4 g / cm3. In embodiments, the adsorbent loading in the carbon molecular sieve monolith is from 0.1 g / cm3to 1.5 g / cm3, from 0.1 g / cm3to 1 g / cm3, or from 0.2 g / cm3to 0.75 g / cm3.

[0024] In embodiments, the carbon molecular sieve monolith 100 has a microcapillary density, also referred to as a cell density of greater than or equal to 300 cells per square inch. In some embodiments, the cell density of the carbon molecular sieve monolith 100 is from 300 cells per square inch to 3000 cells per square inch. The cells per square inch is measured at the first end 110 or the second end 120 of the carbon molecular sieve monolith 100 and indicates the number of microcapillaries 300 in cross section at the surface. In embodiments, the carbon molecular sieve monolith 100 has a cell density of greater than 300 cells per square inch, such as greater than or equal to 400 cells per square inch, greater than or equal to 500 cells per square inch, greater than or equal to 750 cells per square inch, greater than or equal to 1000 cells per square inch, greater than or equal to 1100 cells per square inch, greater than or equal to 1250 cells per square inch, greater than or equal to 1500 cells per square inch, greater than or equal to 1750 cells per square inch, greater than or equal to 2000 cells per square inch, greater than or equal to 2250 cells per square inch, greater than or equal to 2500 cells per square inch, greater than or equal to 2750 cells per square inch, or even greater than or equal to 3000 cells per square inch. In embodiments, the carbon molecular sieve monolith 100 has a cell density from greater than or equal to 1000 cells per square inch to less than 5000 cells per square inch, from greater than or equal to 1000 cells per square inch to less than 3000 cells per square inch, or from greater than or equal to 1500 to less than 3000 cells per square inch.

[0025] In embodiments, the microcapillaries have a cross-sectional diameter that is less than or equal to 1000 µm, such as less than or equal to 750 µm, less than or equal to 500 µm, less than 400 µm, less than 300 µm, less than 250 µm, less than 200 µm, or less than 150 µm. In embodiments, the microcapillaries have a cross-sectional diameter that is from 10 µm to 1000 µm, from 100 µm to 1000 µm, from 200 µm to 1000 µm, from 300 µm to 1000 µm, from 400 µm to 1000 µm, from 500 µm to 1000 µm, from 600 µm to 1000 µm, from 700 µm to 1000 µm, from 800 µm to 1000 µm, from 900 µm to 1000 µm, from 10 µm to 900 µm, from 100 µm to 900 µm, from 200 µm to 900 µm, from 300 µm to 900 µm, from 400 µm to 900 µm, from 500 µm to 900 µm, from 600 µm to 900 µm, from 700 µm to 900 µm, from 800 µm to 900 µm, from 10 µm to 800 µm, from 100 µm to 800 µm, from 200 µm to 800 µm, from 300 µm to 800 µm, from 40085371-WO-PCT / DOW 85371 WO µm to 800 µm, from 500 µm to 800 µm, from 600 µm to 800 µm, from 700 µm to 800 µm, from 10 µm to 700 µm, from 100 µm to 700 µm, from 200 µm to 700 µm, from 300 µm to 700 µm, from 400 µm to 700 µm, from 500 µm to 700 µm, from 600 µm to 700 µm, from 10 µm to 600 µm, from 100 µm to 600 µm, from 200 µm to 600 µm, from 300 µm to 600 µm, from 400 µm to 600 µm, from 500 µm to 600 µm, from 10 µm to 500 µm, from 100 µm to 500 µm, from 200 µm to 500 µm, from 300 µm to 500 µm, from 400 µm to 500 µm, from 10 µm to 500 µm, from 100 µm to 500 µm, from 200 µm to 500 µm, from 300 µm to 500 µm, from 400 µm to 500 µm, from 10 µm to 400 µm, from 100 µm to 400 µm, from 200 µm to 400 µm, from 300 µm to 400 µm, from 10 µm to 300 µm, from 100 µm to 300 µm, from 200 µm to 300 µm, from 300 µm to 300 µm, from 10 µm to 300 µm, from 100 µm to 300 µm, from 200 µm to 300 µm, from 10 µm to 200 µm, from 100 µm to 200 µm or from 10 µm to 100 µm. It should be understood that smaller diameter microcapillaries 300 provide more efficient separation by providing more contacting area, but if the cross-sectional diameter of the microcapillaries 300 is too small, the pressure drop across the carbon molecular sieve monolith 100 increases to undesirable levels.

[0026] In embodiments, the carbon molecular sieve monolith 100 has a void fraction of from 10 v.% to 90 v.%, wherein the void fraction is the volume of gas that is taken in by the microcapillaries. In some embodiments, the carbon molecular sieve monolith 100 has a void fraction of from 10 v.% to 90 v.%, from 15 v.% to 75 v.%, or from 20 v.% to 50 v.%.

[0027] According to embodiments, the two or more sheets of carbon microcapillary film are made from any carbon-forming precursor that can be melt extruded. Appropriate carbon-forming precursors that can be melt extruded may include one or more of polyimide, polyvinylidene chloride, polyetherimide, and polyphenylene oxide, or combinations thereof. Accordingly, in embodiments, the two or more layers of the microcapillary films comprise, consist essentially or, or consist of polyvinylidene chloride, polyimide, polyetherimide, polyphenylene oxide, or combinations thereof. Examples of suitable polyvinylidene chloride is disclosed in U.S. Patent No. 10,239,043, which is incorporated herein by reference in its entirety, and is also described herein below. Examples of suitable polyimides that can be used to form films of embodiments include BTDA-DAPI (Matrimid) as described in U.S. Patent No.8,911,534, which is incorporated herein by reference in its entirety. Examples of suitable polyetherimides are available under the brand name Ultem®, and are disclosed in Fuertes, A. B.; Centeno, T. A., Carbon molecular sieve membranes from polyetherimide. Microporous Mesoporous Mat. 1998, 26 (1), 23-26), which is85371-WO-PCT / DOW 85371 WO hereby incorporated by reference in its entirety. Examples of suitable polyphenylene oxides are disclosed in Yoshimune, M.; Fujiwara, I.; Haraya, K., Carbon molecular sieve membranes derived from trimethylsilyl substituted poly(phenylene oxide) for gas separation. Carbon 2007, 45 (3), 553-560., which is hereby incorporated by reference in its entirety.

[0028] In general, embodiments provide carbon molecular sieve monoliths that are useful for a variety of separations. Such separations may include, but are not necessarily limited to, the following pairs of gases wherein at least one molecule, and in some embodiments both molecules, has / have a representative molecular diameter falling within the 3.0 A to 5.0 A range: ethylene (C2H4) and ethane (C2H6); propylene (C3H6) and propane (C3H8); carbon dioxide (CO2) and nitrogen (N2); carbon dioxide (CO2) and hydrogen (H2), hydrogen (H2) and methane (CH4), N2 and methane (CH4); and n-butane (n-C4H10) and isobutane (i-C4H10). Embodiments of carbon molecular sieve monoliths may be conveniently used in typical separations systems, and particularly in separations systems based upon, for example, pressure or temperature swing principles.

[0029] The carbon molecular sieve monoliths of embodiments may be prepared from a vinylidene chloride copolymer, comprising a vinylidene chloride monomer and at least one additional comonomer. The comonomer may be selected from a variety of materials, including in particular embodiments a vinyl monomer, vinyl chloride monomer, an acrylate monomer, a methacrylate monomer, a styrenic monomer, acrylonitrile, methacrylonitrile, itaconic acid, chlorotrifluoroethylene, and combinations thereof. In embodiments, the vinyl monomers include vinyl chloride, vinyl acetate, acrylonitrile, and combinations thereof. Exemplary acrylate monomers include methyl acrylate, ethyl acrylate, butyl acrylate, and combinations thereof. More particular examples of methacrylate monomers include methyl methacrylate, butyl methacrylate, and combinations thereof. An example of styrenic monomers is styrene itself.

[0030] In embodiments, the vinylidene chloride based copolymer includes at least 60 wt% of vinylidene chloride, based on total weight of the copolymer, such as at least 70 wt%. However, it is further desired that, in embodiments, the vinylidene chloride contains a maximum of 97 wt% vinylidene chloride, and thus in embodiments contains a minimum of at least 3 wt% of the comonomer or comonomer combination, such as from 3 wt% to 40 wt%, from 3 wt% to 30 wt%, or from 3 wt% to 20 wt%.85371-WO-PCT / DOW 85371 WO

[0031] In embodiments, vinylidene chlorides include an acrylate comonomer, such as methyl acrylate, ethyl acrylate, butyl acrylate, or a combination thereof, in an amount from 3 wt% to 30 wt%, based on the weight of the vinylidene chloride as a whole, such as from 3.5 wt% to 15 wt%, or from 4 wt% to 12 wt%. In one or more embodiments, the vinylidene chloride used includes vinyl chloride monomer in an amount from 3 wt% to 30 wt%, such as from 7 wt% to 28 wt%, or from 9 wt% to 25 wt%. In embodiments, the overall weight average molecular weight (Mw) of the vinylidene chloride copolymer may range from 10,000 Mw to 250,000 Mw, such as from 50,000 Mw to 200,000 Mw, or from 60,000 Mw to 150,000 Mw.

[0032] According to one or more embodiments, additives may also be included in the vinylidene chloride. Common additives may include, but are not necessarily limited to, epoxidized oil stabilizers such as epoxidized soybean oil, epoxidized linseed oil, and the diglycidyl ether of bisphenol A. Also frequently employed are liquid plasticizers such as aliphatic and aromatic esters, including for example dibutyl sebacate, acetyl tributyl citrate, dioctyl phthalate, and the like, and combinations thereof. Other common additives may include lubricants, such as polyethylene wax, paraffin wax, oxidized polyethylene wax, and combinations thereof. Lubricants may optionally be included, and may comprise, for example, high density polyethylene, acrylate copolymers and silicone polymers, and combinations thereof. Another group of additives that may be included are acid scavengers such as epoxy compounds, magnesium hydroxide, magnesium oxide, tetrasodium pyrophosphate, calcium phosphate, magnesium phosphate, DHT 4A (a synthetic hydrotalcite-like halogen scavenger available from Kyowa Chemical Industry), calcium oxide, calcium carbonate, and combinations thereof. Antioxidants such as phenolics may also be incorporated. Combinations of any or all of these types of additives may be included in the vinylidene chloride.

[0033] In proportion, and according to embodiments, the total amount of all additives combined be no more than 8 wt%, such as no more than 3 wt%. In embodiments, however, an amount of all additives combined of at least 2 wt% may be used, with use thereof therefore ranging preferably from 2 wt% to 8 wt%, such as from 2 wt% to 3 wt%. Those skilled in the art will be aware of the use of such additives and their indications and contraindications without further direction herein.85371-WO-PCT / DOW 85371 WO

[0034] A variety of means and methods for preparing copolymers can be used to form the vinylidene chloride of embodiments. However, in general any of the typical or conventional methods of polymerization, including but not limited to mass polymerization, suspension polymerization, and emulsion polymerization, and preferably suspension polymerization or emulsion polymerization, may be employed. In embodiments, polymerization is carried out at a temperature that ensures avoidance of degradation of all of the vinylidene chloride components, such as from 10 °C to 120 °C, from 20 °C to 100 °C, or from 30 °C to 90 °C.

[0035] In embodiments, the vinylidene chloride has a peak melting temperature in a range from 100 °C to 200 °C, from 110 °C to 200 °C, from 120 °C to 200 °C, from 130 °C to 200 °C, from 140 °C to 200 °C, from 150 °C to 200 °C, from 160 °C to 200 °C, from 170 °C to 200 °C, from 180 °C to 200 °C, from 190 °C to 200 °C, from 100 °C to 190 °C, from 110 °C to 190 °C, from 120 °C to 190 °C, from 130 °C to 190 °C, from 140 °C to 190 °C, from 150 °C to 190 °C, from 160 °C to 190 °C, from 170 °C to 190 °C, from 180 °C to 190 °C, from 100 °C to 180 °C, from 110 °C to 180 °C, from 120 °C to 180 °C, from 130 °C to 180 °C, from 140 °C to 180 °C, from 150 °C to 180 °C, from 160 °C to 180 °C, from 170 °C to 180 °C, from 100 °C to 170 °C, from 110 °C to 170 °C, from 120 °C to 170 °C, from 130 °C to 170 °C, from 140 °C to 170 °C, from 150 °C to 170 °C, from 160 °C to 170 °C, from 100 °C to 160 °C, from 110 °C to 160 °C, from 120 °C to 160 °C, from 130 °C to 160 °C, from 140 °C to 160 °C, from 150 °C to 160 °C, from 100 °C to 150 °C, from 110 °C to 150 °C, from 120 °C to 150 °C, from 130 °C to 150 °C, from 140 °C to 150 °C, from 100 °C to 140 °C, from 110 °C to 140 °C, from 120 °C to 140 °C, from 130 °C to 140 °C, from 100 °C to 130 °C, from 110 °C to 130 °C, from 120 °C to 130 °C, from 100 °C to 120 °C, from 110 °C to 120 °C, from 100 °C to 110 °C.

[0036] In embodiments, the vinylidene chloride is formed into a resin. The resin is loaded into an extruder and heated to form a polymer melt. The resin may be heated to form a polymer melt at a temperature of from 100 °C to 200 °C. The resin may be heated to form a polymer melt at a temperature of from 100 °C to 200 °C, from 125 °C to 180 °C, from 150 °C to 175 °C or from 155 °C to 170 °C.

[0037] The polymer melt is introduced into a microcapillary film die to form microcapillaries in the polymer melt. In embodiments, the microcapillary film die has a split body design. In embodiments, the microcapillary film die includes an insert. The insert may be an air manifold85371-WO-PCT / DOW 85371 WO insert or any other fluid (water, liquid fluid, low carbon yield polymer such as polyethylene) that could leave the capillary open after the thermal treatment. The width of the insert and die slit opening may be from 0.5 inches to 100 inches, from 1 inch to 90 inches, from 3 inches to 80 inches, of from 5 inches to 75 inches.., In embodiments, the insert includes parallel hollow pins positioned near the exit of the microcapillary film die. The insert may comprise from 2 to 2000 hollow pins, from 10 to 1500 hollow pins, or from 25 to 1000 hollow pins. The parallel hollow pins are used to introduce air into the polymer melt to form the microcapillaries in the polymer melt. In embodiments, the parallel hollow pins are used to introduce air into the polymer melt. The ratio of air flow rate to the volumetric polymer melt flow rate will determine the void fraction of the microcapillary film and monolith. The microcapillary size and wall thickness will be determined by the ratio of the polymer and air flow. In embodiments, the air feed pressure may be from 1 pound per square inch of gauge pressure (psig) to 100 psig, such as from 5 psig to 75 psig, from 10 psig to 50 psig, or from 20 psig to 40 psig. In embodiments, the air flow rate may be from 1 standard cubic centimeter per minute (sccm) to 2000 sccm, such as from 5 sccm to 500 sccm, from 10 sccm to 250 sccm, or from 15 to 200 sccm. The polymer flow rate may be the same range as air flow rate.

[0038] After introducing the polymer melt into a microcapillary film die to form microcapillaries in the polymer melt, the polymer melt is then quenched to form a microcapillary film. Quenching the polymer melt may include passing the polymer melt through a water bath. The water bath may be at from 1 °C to 80 °C, such as room temperature (about 22 °C).

[0039] After the polymer melt is quenched to form a microcapillary film, layers of the microcapillary film may be created. In some embodiments, the layers of microcapillary film may be created while the microcapillary film is in the water bath. In embodiments, creating the layers of microcapillary films includes layering a single microcapillary film upon itself. In embodiments, creating the layers of microcapillary films includes stacking multiple microcapillary films. In embodiments, creating the layers of microcapillary films includes both layering a single microcapillary film upon itself (such as by folding a single microcapillary film); in such embodiments, the layers of the same microcapillary film may be referred to as the first sheet of microcapillary film and the second sheet of microcapillary film and stacking multiple microcapillary films. In embodiments, the layers of microcapillary films may be aligned in parallel such that first axial ends of each microcapillary film are positioned at the first end of the carbon85371-WO-PCT / DOW 85371 WO molecular sieve monolith and second axial ends of each microcapillary film are aligned at the second end of the carbon molecular sieve monolith, and microcapillaries extends from the first end of each microcapillary film to the second end of each microcapillary film.

[0040] In embodiments, the microcapillary film is stretched while creating layers of the microcapillary film. The stretched microcapillary film has thickness ranging from 10 µm to 1000 μm, such as from 20 μm to 500 μm, or from 50 μm to 200 μm. This stretching may, in embodiments, be particularly effective in inducing more rapid crystallization and in increasing, and therefore improving, alignment of the polyvinylidene chloride crystallites. Desirably the stretch ratio ranges from 1 to 8, such as from 1 to 6, from 1 to 4, or from 2 to 4.

[0041] It has been found that ensuring a given level of crystallinity within the designated range helps achieve the desired average micropore size and average micropore volume, following the pyrolysis, in the final carbon molecular sieve. It is noted that homopolymerized polyvinylidene chloride generally exhibits an as-polymerized crystallinity greater than 75 %, and that it has been found to be significant that the polyvinylidene chloride be either copolymerized with an adequate amount of at least one of the listed monomers, or melt-extruded (with or without stretching), or both, in order to ensure the designated level of precursor (i.e., pre-pyrolysis) crystallinity (i.e., from 25 % to 75 %) specified herein. Thus, inclusion of a comonomer generally helps to reduce precursor crystallinity to ensure the desired range, and also to reduce the melt temperature and thereby improve processability of the resulting copolymer. In general, inclusion of bulkier monomers may tend to reduce overall copolymer crystallinity by a greater amount than inclusion of less bulky monomers. Thus, for example, butyl acrylate will tend to reduce crystallinity more than, for example, methyl acrylate or ethyl acrylate, assuming such is / are used in the same mole percent (mol%) based on final copolymer composition.

[0042] In some embodiments, after creating layers of the microcapillary films, the layers of microcapillary films may be laminated. The microcapillary film layers may be laminated by placing a plurality of softened layers of microcapillary films adjacent to one another and allowing the layers of microcapillary films to cool for from 1 minute to 48 hours to form a laminate. The layers of microcapillary films may be laminated at a temperature of from 1 °C and 60 °C, for example, at room temperature (25 °C). The layers of microcapillary films may be laminated for from 1 minute to 48 hours, from 1 minute to 36 hours, 1 minute to 24 hours, from 2 minutes to 2485371-WO-PCT / DOW 85371 WO hours, from 5 minutes to 24 hours, from 30 minutes to 24 hours, from 1 hour to 24 hour, from 4 hours to 24 hours, or from 8 hours to 24 hours. After the layers of microcapillary films are created, the layers of microcapillary films at least partially crystalize. Allowing the layers of microcapillary films to cool to form a laminate allows the layers of microcapillary films to fully crystalize. The time needed to allow the layers of microcapillary films to fully crystalize and form a laminate is dependent on several factors, including the temperature that the layers are cooled to, and the degree to which the microcapillary films were stretched during formation and quenching. Allowing the layers of microcapillary films to cool to form a laminate stabilizes the structure of the layers of microcapillary films.

[0043] In some embodiments, the layers of microcapillary films are placed into a mold. The mold has the shape of the desired carbon molecular sieve monolith. The mold may be made of any material that is capable of withstanding the processing pressures and temperatures described herein below. In some embodiments, the mold may be lined with a liner that prevents or mitigates the layers of microcapillary films from adhering to the mold. In some embodiments, the mold may be treated with a coating that prevents or mitigates the layers of microcapillary films from adhering to the mold. In one or more embodiments, the mold may be ceramic.

[0044] In embodiments, after the layers of microcapillary films have been loaded into the mold, the mold with the layers of microcapillary films placed therein is heated to a temperature that softens the layers of microcapillary films, such as, for example, a temperature that is at or above the softening point or glass transition temperature of the layers of microcapillary films. Because the layers of microcapillary films are constrained by the mold, when the layers of microcapillary films are heated to a temperature that is at or above the softening point or glass transition temperature of the layers of microcapillary films, the layers of microcapillary films soften and the layers of microcapillary films will become joined with adjacent layers of microcapillary films in which they are in physical contact, thereby forming a polymer monolith. Heating the mold containing the layers of microcapillary films will stabilize, or "lock," the structure of the layers of microcapillary films prior to carbonization thereof. As used herein, the term “polymer monolith” refers to two or more microcapillary films that are joined together into a unitary structure that is not easily separable.85371-WO-PCT / DOW 85371 WO

[0045] In embodiments, the layers of microcapillary films that are laminated or the layers of microcapillary films that are placed into the mold may be heated to a temperature from 50 °C to 350 °C, from 75 °C to 350 °C, from 100 °C to 350 °C, from 125 °C to 350 °C, from 150 °C to 350 °C, from 175 °C to 350 °C, from 200 °C to 350 °C, from 225 °C to 350 °C, from 250 °C to 350 °C, from 275 °C to 350 °C, from 300 °C to 350 °C, from 325 °C to 350 °C, from 50 °C to 325 °C, from 75 °C to 325 °C, from 100 °C to 325 °C, from 125 °C to 325 °C, from 150 °C to 325 °C, from 175 °C to 325 °C, from 200 °C to 325 °C, from 225 °C to 325 °C, from 250 °C to 325 °C, from 275 °C to 325 °C, from 300 °C to 325 °C, from 50 °C to 300 °C, from 75 °C to 300 °C, from 100 °C to 300 °C, from 125 °C to 300 °C, from 150 °C to 300 °C, from 175 °C to 300 °C, from 200 °C to 300 °C, from 225 °C to 300 °C, from 250 °C to 300 °C, from 275 °C to 300 °C, from 50 °C to 275 °C, from 75 °C to 275 °C, from 100 °C to 275 °C, from 125 °C to 275 °C, from 150 °C to 275 °C, from 175 °C to 275 °C, from 200 °C to 275 °C, from 225 °C to 275 °C, from 250 °C to 275 °C, from 50 °C to 250 °C, from 75 °C to 250 °C, from 100 °C to 250 °C, from 125 °C to 250 °C, from 150 °C to 250 °C, from 175 °C to 250 °C, from 200 °C to 250 °C, from 225 °C to 250 °C, from 50 °C to 225 °C, from 75 °C to 225 °C, from 100 °C to 225 °C, from 125 °C to 225 °C, from 150 °C to 225 °C, from 175 °C to 225 °C, from 200 °C to 225 °C, from 50 °C to 200 °C, from 75 °C to 200 °C, from 100 °C to 200 °C, from 125 °C to 200 °C, from 150 °C to 200 °C, from 175 °C to 200 °C, 130 °C to 160 °C, from 50 °C to 175 °C, from 75 °C to 175 °C, from 100 °C to 175 °C, from 125 °C to 175 °C, from 150 °C to 175 °C, from 50 °C to 150 °C, from 75 °C to 150 °C, from 100 °C to 150 °C, from 125 °C to 150 °C, from 50 °C to 125 °C, from 75 °C to 125 °C, from 100 °C to 125 °C, from 50 °C to 100 °C, from 75 °C to 100 °C, or from 50 °C to 75 °C.

[0046] According to embodiments, the heating is conducted for a duration that is sufficient to reduce the weight of the layers of microcapillary films by at least 5%, at least 7%, at least 10%, at least 12%, at least 15%, at least 17%, or at least 20%. Accordingly, in embodiments, the heating is conducted for a duration that is sufficient to reduce the weight of the layers of microcapillary films by 5% to 20%, 7% to 20%, 10% to 20%, 12% to 20%, 15% to 20%, 17% to 20%, 5% to 17%, 7% to 17%, 10% to 17%, 12% to 17%, 15% to 17%, 5% to 15%, 7% to 15%, 10% to 15%, 12% to 15%, 5% to 12%, 7% to 12%, 10% to 12%, 5% to 10%, 7% to 10%, 5% to 7%.

[0047] According to embodiments, the mold with the layers of microcapillary films placed therein may optionally be returned to room temperature after the mold with the layers of85371-WO-PCT / DOW 85371 WO microcapillary films placed therein has been heated to the temperature that joins the layers of microcapillary films to adjacent layers of microcapillary films. This cooling allows the mold with the layers of microcapillary films placed therein to be more easily handled and transported. However, in embodiments, the mold with the layers of microcapillary films placed therein does not need to be cooled to room temperature before further processing. Additionally, in embodiments, the polymer monolith may optionally be removed from the mold before further processing to form the carbon molecular sieve monolith, such as the further processing described below. However, in one or more embodiments, the polymer monolith is not removed from the mold before further processing to form the carbon molecular sieve monolith.

[0048] Heating the mold containing the layers of microcapillary films will at least 10 % dehydrochlorinate the layers of microcapillary films. As used herein, the term "at least 10 % dehydrochlorinated" means that the layers of microcapillary films have been treated, by removing hydrogen chloride, to a point at which the copolymer precursor no longer melts and, in fact, begins to become infusible. It is well-accepted in the art that such a change in molecular kinetics begins to occur at a point of approximately 10 % dehydrochlorination and is completed or maintained as the level of dehydrochlorination increases above that point.

[0049] Heating the layers of microcapillary films may be done in air for convenience, but other atmospheres, such as N2and other inert gases or oxidizing gases such as CO2, or combinations thereof, may also or alternatively be used, since generally only minor levels of oxidation of the copolymer are anticipated within the overall given temperature range.

[0050] The layers of microcapillary films may be heated for from 1 hour (hr) to 48 hr, such as from 1 hr to 24 hr, or from 1 hr to 12 hr, as needed to reach the at least 10 % dehydrochlorination point, at which the copolymer begins to become infusible, (i.e., no longer able to be melted). The dehydrochlorination degree can vary from 10 % to 100 %, depending upon temperature and time. While it is desirable that substantially all of the copolymer be dehydrochlorinated to the desired extent, it will be recognized that presence of a minor amount, desirably less than 2 % by weight, of precursor that is not at least 10 % dehydrochlorinated may be acceptable. Where more than visual confirmation of the beginning of infusibility is desired, additional confirmation of the percentage of dehydrochlorination may be obtained by means of, for example, Thermo Gravimetric Analysis (TGA), using standard and well-known methods and equipment.85371-WO-PCT / DOW 85371 WO

[0051] Following heating the mold containing the layers of microcapillary films, the resulting polymer monolith is pyrolyzed to form the carbon molecular sieve monolith. The pyrolysis may result in at least 90 wt% of the copolymer becoming carbonized, such as at least 95 wt%, or at least 99 wt%. This pyrolysis may also be referred to as "carbonization," because the result thereof is that the copolymer is converted to the carbon-only, or near carbon-only, skeleton of its copolymer structure, (i.e., all or virtually all atoms other than carbon have been removed, but the carbon-carbon bonds remain substantially intact), and the carbon molecular sieve monolith may now be termed to be "carbonaceous." Therefore, once the polymer monolith is pyrolyzed, the microcapillary films become carbon microcapillary films, as the microcapillary films become carbonized.

[0052] The pyrolysis may be carried out using any means generally known to those skilled in the art, but may be carried out at an attained maximum temperature within the range of from 600 °C to 1500 °C, from 700 °C to 1500 °C, from 800 °C to 1500 °C, from 900 °C to 1500 °C, from 1000 °C to 1500 °C, from 1100 °C to 1500 °C, from 1200 °C to 1500 °C, from 1300 °C to 1500 °C, from 1400 °C to 1500 °C, from 600 °C to 1400 °C, from 700 °C to 1400 °C, from 800 °C to 1400 °C, from 900 °C to 1400 °C, from 1000 °C to 1400 °C, from 1100 °C to 1400 °C, from 1200 °C to 1400 °C, from 1300 °C to 1400 °C, from 600 °C to 1300 °C, from 700 °C to 1300 °C, from 800 °C to 1300 °C, from 900 °C to 1300 °C, from 1000 °C to 1300 °C, from 1100 °C to 1300 °C, from 1200 °C to 1300 °C, from 600 °C to 1200 °C, from 700 °C to 1200 °C, from 800 °C to 1200 °C, from 900 °C to 1200 °C, from 1000 °C to 1200 °C, from 1100 °C to 1200 °C, from 600 °C to 1100 °C, from 700 °C to 1100 °C, from 800 °C to 1100 °C, from 900 °C to 1100 °C, from 1000 °C to 1100 °C, from 600 °C to 1000 °C, from 700 °C to 1000 °C, from 800 °C to 1000 °C, from 900 °C to 1000 °C, from 600 °C to 900 °C, from 700 °C to 900 °C, from 800 °C to 900 °C, from 600 °C to 800 °C, from 700 °C to 800 °C, or from 600 °C to 700 °C.

[0053] Following pyrolysis, the carbon molecular sieve monolith may be activated by using any means generally known to those skilled in the art. In embodiments, the carbon molecular sieve monolith may be activating by using one or more oxidants. The oxidants may include steam, carbon dioxide, air, or combinations thereof. In embodiments, activating the carbon molecular sieve monolith may cause the carbon molecular sieve monolith to lose from 1 % to 30 % weight. In embodiments, activating the carbon molecular sieve monolith may cause the carbon molecular sieve monolith to lose from 0 % to 50 % weight, from 0.5 % to 40 % weight, from 0.75 % to 3585371-WO-PCT / DOW 85371 WO % weight, or from 1 % to 30 % weight. Activating the carbon molecular sieve monolith will create additional microporosity, which will increase the adsorption capacity of the carbon molecular sieve monolith. Furthermore, activating the carbon molecular sieve monolith may enlarge the micropore size, which will enhance the adsorption rate.

[0054] Following activating, embodiments of the carbon molecular sieve monolith has an average micropore size ranging from 3.0 A to 6.0 A. In particular embodiments, the average micropore size ranges from 4.0 A to 4.3 A, and is thus capable of admitting propylene molecules while excluding propane molecules. In another embodiment the average micropore size ranges from 3.7 A to 4.1 A, and is thus capable of admitting ethylene molecules while excluding ethane molecules. In embodiments, the average micropore size ranges from 3.64 A to 3.8 A, and is thus capable of admitting nitrogen molecules while excluding methane molecules. In embodiments, the average micropore size ranges from 3.0 A to 3.64 A, and is thus capable of admitting carbon dioxide molecules while excluding nitrogen molecules. In embodiments, the average micropore size ranges from 4.3 A to 5.0 A, and is thus capable of admitting n-butane molecules while excluding / so-butane molecules. Thus, the inventive compositions are particularly desirable for these particular separations, but may, in other non-limiting embodiments, be useful in certain other separations. EXAMPLES

[0055] The following Examples are offered by way of illustration and are presented in a manner such that one skilled in the art should recognize are not meant to be limiting to the present disclosure as a whole or to the appended claims.

[0056] SARAN 711, which is a polyvinylidene chloride containing about 8.5 wt% methyl acrylate that is commercially available from SK Global SARAN, was loaded into an extruder. The extruder was a 0.75-inch diameter single screw extruder with three-barrel temperature zones. The extruder had a microcapillary film die. The microcapillary film die had a simple split body design with a two-inch wide air manifold insert that contains 42 parallel hollow pins positioned near the exit of the die. The air feed pressure was about 30 psig, and the flow rate was about 17 sccm. An elbow adaptor positioned the microcapillary film die such that the extrudate was directed into a water bath.85371-WO-PCT / DOW 85371 WO

[0057] First, the elbow and die were heated using metal heating elements that were clamped in place. The temperatures of the three zones of the extruder, the elbow, and die were increased from 155 °C to 170 °C until no unmelted resin was seen in the extruded film. The microcapillary film die was used to introduce air into the polymer melt, thereby forming microcapillaries. The extruder was feed through a hopper and the extruder ran at about 50 rpm. The air flow rate through the pins in the die was 17 sccm. Polyethylene (PE) resin was periodically fed into the extruder to flush out char build up.

[0058] Upon extrusion from the die, the microcapillary film was quenched into a room temperature (approximately 22 °C) water bath and the microcapillary film was wrapped around a guide roll at the bottom of the water bath. The microcapillary film was then pulled out of the water bath by a winder at 10.5 rpm to achieve about 10 mil (250 µm) film thickness. The winder also stretched the film near the exit of the die and reduced both film width and film thickness. The winder was used to wind the film on to a 5 inch outside diameter winder drum. To make a laminate, about 10 layers of the microcapillary film were wound onto the winder drum and allowed to cool for about 10 minutes.

[0059] Single layers of the extruded microcapillary film were cut into 5 cm long pieces to form tapes. The laminate was also cut into 5 cm long pieces to form tapes. The width of the film was about 1.4 cm.

[0060] The tapes were then placed between two honeycomb ceramic plates. Two sheets of Whatman 1003-125 filter paper were placed between the tapes and the honeycomb ceramic plates to provide a cushion. The tape / filter paper / honeycomb ceramic plate combination was then placed an oven the combination was constantly purged by air at a rate of 2 liters per minute (L / min) throughout the treatment cycle. The oven was then heated to a temperature of 130 °C at a ramp rate of 1 °C per minute, and held at 130 °C for 24 hours. After 24 hours, the oven was allowed to cool, and the resulting polymer monolith was removed from the oven after the oven had cooled to below 60 °C.

[0061] The polymer monolith was then placed into a quartz tube furnace. The quartz tube furnace had a diameter of six inches and a length of 24 inches. Once the polymer monolith was loaded into the quartz tube furnace, the polymer monolith was constantly purged with nitrogen at85371-WO-PCT / DOW 85371 WO a rate of 5 L / min. Then, the quartz tube furnace was raised to a temperate of 250 °C at a ramp rate of 0.1 °C per minute. The quartz tube furnace was then heated to the pyrolysis temperate shown in Table 1 (either 600 °C or 900 °C, depending on the sample) at a ramp rate of 3 °C per minute. The quartz tube was held at the pyrolysis temperature for 120 minutes. The quartz tube was then allowed to cool, and the resulting carbon molecular sieve monoliths were removed from the quartz tube after the quartz oven had cooled to below 60 °C. Table 1: Example Details and Pyrolysis Temperature

[0062] Adsorption was performed using a Magnetic Suspension Balance (MSB). Samples of the carbon molecular sieve monoliths of from 300 milligrams (mg) to 500 mg were loaded into cells of the MSB. The temperature was raised and kept at 100 °C for 4 hours under vacuum conditions to perform vacuum pretreatment and to desorb any pre-adsorbed species. At the end of the 4 hours under vacuum conditions, mass readings were checked for stability to ensure the desorption step was completed. Then, the temperature was set to the adsorption temperature of 50 °C. The pressure was then increased stepwise to measure the adsorbed amount at different pressures. The carbon adsorbent was stored in a lab air environment between tests. Repeat adsorption was performed following the same 100 °C vacuum pretreatment steps outlined above to check the recyclability of the material.85371-WO-PCT / DOW 85371 WO

[0063] FIG. 2 shows a cross-section of Example 1. FIG. 3 shows a cross-section of Example 3. Regular microcapillaries (long axis 170 micron, short axis 93 micron) were evenly distributed in both Example 1 and Example 3. The void space between the layers was negligible, suggesting good lamination and suggesting that only one microcapillaries in Example 3 is available for the distribution of feed fluid for adsorption.

[0064] Table 2 shows the properties of Example 3. The cell density was 18700 cells per square inch (cpsi). The void fraction of example 3 was about 37%, which provided good routes for fluid flow. As the entire wall was made of the carbon adsorbent (i.e. there was no support that occupied the overall volume), a very high adsorbent loading was achieved at about 0.76 g / cm3. Table 2: Various Properties of Example 3

[0065] FIGs. 4 and 5 show the multi-cycle CO2adsorption test results for Example 1 and Example 2, respectively. The Example 2 showed stable isotherm throughout the 3 cycles and 1 month of storage in lab atmosphere. Example 1 showed a clear decline of adsorption capacity overtime. Without being bound by theory, it is believed that the higher temperature of pyrolysis created a more stable carbon material in Example 2.

[0066] FIG. 6 shows the comparison of CO2 isotherm in Example 2 and Comparative Examples 1 and 2. Example 2 had a higher capacity than the incumbent carbon adsorbent. Even higher CO2adsorption capacity is expected after further activation of Example 2.

[0067] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting. As used in the specification and appended claims, the85371-WO-PCT / DOW 85371 WO singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0068] It is noted that the terms “substantially” and “about” may be utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. The term “substantially” is used herein also to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. Thus, it is used to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation, referring to an arrangement of elements or features that, while in theory would be expected to exhibit exact correspondence or behavior, may in practice embody something less than exact.

[0069] It is noted that one or more of the following claims utilize the term “wherein” as a transitional phrase. For the purposes of defining the present technology, it is noted that this term is introduced in the claims as an open-ended transitional phrase that is used to introduce a recitation of a series of characteristics of the structure and should be interpreted in like manner as the more commonly used open-ended preamble term “comprising.”

[0070] It should be understood that where a first component is described as “comprising” or “including” a second component, it is contemplated that, in some embodiments, the first component “consists” or “consists essentially of” the second component. Additionally, the term “consisting essentially of” is used in this disclosure to refer to quantitative values that do not materially affect the basic and novel characteristic(s) of the disclosure.

[0071] It should be understood that any two quantitative values assigned to a property or measurement may constitute a range of that property or measurement, and all combinations of ranges formed from all stated quantitative values of a given property or measurement are contemplated in this disclosure.

[0072] While particular embodiments have been illustrated and described herein, it should be understood that various other changes and modifications may be made without departing from85371-WO-PCT / DOW 85371 WO scope of the claimed subject matter. Moreover, although various aspects of the claimed subject matter have been described herein, such aspects need not be utilized in combination. It is therefore intended that the appended claims cover all such changes and modifications that are within the scope of the claimed subject matter.

Claims

85371-WO-PCT / DOW 85371 WO CLAIMS1. A method for forming a carbon molecular sieve monolith, the method comprising: loading a resin into an extruder; heating the resin to form a polymer melt; introducing the polymer melt into a microcapillary film die to form microcapillaries in the polymer melt; quenching the polymer melt to form a microcapillary film; creating layers of microcapillary films; laminating the layers of microcapillary films or placing the layers of microcapillary films into a mold; heating the layers of microcapillary films to a temperature of from 50 °C to 350 °C to form a polymer monolith; pyrolizing the polymer monolith by heating the polymer monolith to a temperature of from 500 °C to 1700 °C to form the carbon molecular sieve monolith; and activating the carbon molecular sieve monolith using one or more oxidants.

2. The method of claim 1, wherein the method further comprises stretching the microcapillary film near an exit of the microcapillary film die.

3. The method of claim 1 or claim 2, wherein the creating layers of microcapillary films comprises layering a single microcapillary film upon itself.

4. The method of claim 1 or claim 2, wherein the creating the layers of microcapillary films comprises stacking multiple microcapillary films.

5. The method of any one of claims 1-4, wherein the method further comprises allowing the layers of microcapillary films to cool for from 1 minute to 48 hours to form a laminate.

6. The method of any one of claims 1 to 5, wherein the resin comprises polyvinylidene chloride.

7. The method of any one of claims 1 to 6, wherein heating the resin to form a polymer melt comprises heating the resin to a temperature of from 155 °C to 170 °C.85371-WO-PCT / DOW 85371 WO 8. The method of any one of claims 1 to 7, wherein the pyrolizing step comprises heating the polymer monolith to a temperature of from 600 °C to 1500 °C.

9. The method of any one of claims 1 to 8, wherein heating the mold containing the microcapillary film comprises heating the mold containing the microcapillary film to a temperature of from 130 °C to 160 °C.

10. A carbon molecular sieve monolith comprising: a first end and a second end opposite the first end; two or more sheets of carbon microcapillary films aligned in parallel such that first axial ends of the two or more sheets of carbon microcapillary films are positioned at the first end of the carbon molecular sieve monolith and second axial ends of the one or more sheets of carbon microcapillary films are aligned at the second end of the carbon molecular sieve monolith; and microcapillaries extending from the first end of the one or more sheets of carbon microcapillary films to the second end of the one or more sheets of carbon microcapillary films, wherein outer surfaces of the two or more sheets of carbon microcapillary films are joined together to form the carbon molecular sieve monolith, and the carbon molecular sieve monolith has a cell density of greater than or equal to 300 cells per square inch.

11. The carbon molecular sieve monolith of claim 10, wherein the two or more sheets of carbon microcapillary film are made from polyvinylidene chloride.

12. The carbon molecular sieve monolith of any one of claims 10 or 11, wherein the carbon molecular sieve monolith has a void fraction of from 10 v.% to 90 v.%.

13. The carbon molecular sieve monolith of any one of claims 10 to 12, wherein the carbon molecular sieve monolith comprises 10 or more sheets of carbon microcapillary film.

14. The carbon molecular sieve monolith of any one of claims 10 to 13, wherein the cell density of the carbon molecular sieve monolith is from 300 cells per square inch to 3000 cells per square inch.85371-WO-PCT / DOW 85371 WO 15. The carbon molecular sieve monolith of any one of claims 10 to 14, wherein adsorbent loading in the carbon molecular sieve monolith is at least 0.1 g / cm3.

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