Porous substrates for carrying adsorbents or other active materials

Abstract

The present invention relates to a porous substrate comprising a continuous graphite phase and a glass and / or ceramic phase. The graphite phase and the glass and / or ceramic phase together form a continuous interconnected pore structure. The total pore volume of the porous substrate is at least 40% as determined by mercury porometry. The porous substrate has electrical conductivity. The present invention also relates to a method of forming a porous substrate comprising extruding, drying, and firing the extruded extrudable composition, the extrudable composition comprising a binder and / or a sintering aid.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 535334, filed August 30, 2023, pursuant to 35 USC §119, the contents of which are incorporated herein by reference in their entirety. Background Technology

[0003] One method for removing CO2 from a point source or ambient air involves passing a CO2-laden stream through a bulk material containing an adsorbent that adsorbs CO2. The CO2 can then be removed by desorption (e.g., via heating the bulk material). A convenient way to heat the bulk material is via resistance heating; however, conventional conductive bulk materials have poor mechanical strength. Summary of the Invention

[0004] Various aspects of this disclosure provide a porous substrate comprising a continuous graphite phase and a glassy and / or ceramic phase. The graphite phase and the glassy and / or ceramic phase together form a continuous, interconnected porous structure. The total pore volume of the porous substrate is determined to be at least 40% by mercury porosimetry. The porous substrate is electrically conductive.

[0005] Various aspects of this disclosure provide a monolithic substrate comprising a continuous graphite phase and a glassy and / or ceramic phase. The graphite phase and the glassy and / or ceramic phase together form a continuous, interconnected porous structure. The total pore volume of the porous substrate is determined to be 40% to 95% by mercury porosimetry. The porous substrate also includes a coating on the continuous, interconnected porous structure, said coating comprising an active material, such as a catalyst, an adsorbent for adsorbing and desorbing CO2, or a combination thereof. The porous substrate described herein is electrically conductive.

[0006] In various aspects of this disclosure, the porous substrate can be an extruded and sintered product of an extrudable composition. The extrudable composition includes a binder and / or sintering aid. The extrudable composition may also include graphite particles. The extrudable composition can be an extrudable paste.

[0007] Various aspects of this disclosure provide a porous substrate comprising an extruded and sintered product of an extrudable composition. The extrudable composition includes a binder and / or sintering aid. The extrudable composition also includes graphite particles, comprising graphite plates, graphite sheets, or combinations thereof. The porous substrate comprises a continuous graphite phase and a glassy and / or ceramic phase. The graphite phase and the glassy and / or ceramic phase together form a continuously interconnected pore structure. The total pore volume of the porous substrate is determined to be at least 40% by mercury porosimetry. The porous substrate is electrically conductive.

[0008] In various aspects, this disclosure provides a method for forming a porous substrate. The method includes extruding an extrudable composition. The method includes drying the extruded composition. The method further includes calcining the dried extruded composition to form a porous substrate.

[0009] In various aspects, this disclosure provides a method for forming a porous substrate. The method includes extruding an extrudable composition. The extrudable composition includes a binder and / or a sintering aid. The extrudable composition also includes graphite particles, comprising graphite plates, graphite sheets, or combinations thereof. The method includes drying the extruded composition. The method further includes sintering the extruded composition to form a porous substrate. The porous substrate comprises a continuous graphite phase and a glass and / or ceramic phase. The graphite phase and the glass and / or ceramic phase together form a continuously interconnected pore structure. The total pore volume of the porous substrate is determined to be at least 40% by mercury porosimetry. The porous substrate is electrically conductive.

[0010] In various aspects, this disclosure provides a method for forming a porous substrate. The method includes extruding an extrudable composition. The extrudable composition includes a binder and / or a sintering aid. The extrudable composition includes graphite particles, including graphite plates, graphite sheets, or combinations thereof. The extrudable composition also includes hollow glass beads. The method includes drying the extruded composition. The method further includes firing the extruded composition to form a porous substrate. Firing includes firing the extruded composition in a furnace including an unheated insert portion, a heated central portion maintained at a temperature of about 920°C to 1000°C, and an unheated outlet portion. The distance from the inlet of the unheated insert portion to the outlet of the unheated outlet portion is the total length (L) of the furnace. The method includes moving the extruded composition through the furnace at a rate of about 0.01*L per minute to 0.1*L per minute, further including holding the extruded composition stationary in the heated central portion for a heating duration of 5 minutes to 1 hour. Firing is completed over a duration of 20 minutes to 2 hours. The porous substrate comprises a continuous graphite phase and a glassy and / or ceramic phase, wherein the graphite phase and the glassy and / or ceramic phase together form a continuous interconnected pore structure. The total pore volume of the porous substrate is determined to be at least 40% by mercury porosimetry. The porous substrate is electrically conductive.

[0011] In various aspects, this disclosure provides a method for forming a porous substrate. The method includes extruding an extrudable composition. The extrudable composition includes a binder and / or a sintering aid. The extrudable composition also includes hollow glass beads. The method includes drying the extruded composition. The method further includes firing the extruded composition to form a porous substrate. Firing includes firing the extruded composition in a furnace. The furnace includes an unheated insert portion, a heated central portion maintained at a temperature of about 920°C to 1000°C, and an unheated outlet portion. The distance from the inlet of the unheated insert portion to the outlet of the unheated outlet portion is the total length (L) of the furnace. The method includes moving the extruded composition through the furnace at a rate of about 0.01*L per minute to 0.1*L per minute, further including holding the extruded composition stationary in the heated central portion for a heating duration of 5 minutes to 1 hour. Firing is completed over a duration of 20 minutes to 2 hours.

[0012] In various aspects, this disclosure provides a method for using a porous substrate comprising a coating that includes an adsorbent for adsorbing and desorbing CO2. The method includes exposing the porous substrate to an airflow comprising CO2 to at least partially adsorb CO2 from the airflow into the coating on the porous substrate. The method further includes desorbing CO2 from the coating on the porous substrate.

[0013] In various aspects, the porous substrates of this disclosure have a combination of low thermal mass and high thermal conductivity, thereby providing more efficient heating and cooling than other porous substrates. In various aspects, the porous substrate includes a continuous graphite phase dispersed throughout the ceramic and / or glass phase, thus providing higher conductivity and increased bonding between the graphite and the ceramic / glass phase compared to porous substrates that include a graphite coating but lack graphite within the ceramic / glass phase. In various aspects of this disclosure, the porous substrate may include a preferred orientation of the graphite particles, which, in various aspects, can provide higher electrical and / or thermal conductivity in the extrusion direction than in the direction perpendicular to the extrusion direction compared to corresponding porous substrates with randomly oriented graphite particles or non-elongated particles that cannot be oriented. In various aspects of this disclosure, the porous substrates of this disclosure can have higher electrical and / or thermal conductivity than other glass / ceramic substrates with similarly low densities. In various aspects of this disclosure, the porous substrate can be conductive, thereby enabling convenient and uniformly distributed resistance heating (i.e., Joule heating via applying a potential to the porous substrate). In various aspects, the ceramic and / or glassy phases provide high strength and / or mechanical integrity to the porous substrates of this disclosure. In various aspects, the porous substrates of this disclosure can be readily manufactured by extrusion, drying, and firing a single extrudable composition comprising graphite particles and sintering aids and / or binders, avoiding additional steps for incorporating the graphite phase into the porous substrate. In various aspects, the porous substrates of this disclosure possess a combination of high porosity, low mass (e.g., low bulk density), high strength, high electrical conductivity, high thermal conductivity, low operating costs, low manufacturing costs, and / or ease of manufacture not found in other porous substrates.

[0014] Various aspects of the methods for forming porous substrates disclosed herein provide a faster method for firing (e.g., sintering) extruded and extrudable compositions than other methods. For example, compositions typically comprising hollow glass beads require more than 10-20 hours to complete firing, while in various embodiments of the methods disclosed herein, firing can be completed in 2 hours or less, thus providing a less costly and more efficient method for producing porous substrates. In various aspects of the methods disclosed herein, the produced porous substrates may have the same or similar properties as porous substrates produced using conventional 10-20 hour firing techniques. Attached Figure Description

[0015] The accompanying drawings illustrate various aspects of this disclosure by way of example rather than limitation.

[0016] Figure 1 An example substrate with a honeycomb form is illustrated according to the various aspects disclosed herein.

[0017] Figure 2 Methods for forming porous substrates according to various aspects disclosed herein are illustrated.

[0018] Figure 3A This is a SEM image of a portion of the wall of a porous substrate in a honeycomb form prepared according to the examples described herein, the porous substrate comprising a glass and / or ceramic phase and a continuous graphite phase.

[0019] Figure 3B yes Figure 3A A magnified view of a portion of the SEM image.

[0020] Figure 4 It is illustrated according to various aspects Figure 1 The temperature distribution of the furnace shown is the temperature relative to the distance from the opening of the furnace's insertion section.

[0021] Figure 5 It is based on SEM images of graphite sheets from various aspects. Detailed Implementation

[0022] Reference will now be made to certain aspects of the disclosed subject matter. While the disclosed subject matter will be described in conjunction with the enumerated claims, it should be understood that the illustrated subject matter is not intended to limit the claims to the disclosed subject matter.

[0023] Throughout this document, values ​​expressed in range format should be interpreted flexibly to include not only the numerical value explicitly stated as the limit of the range but also all individual numerical values ​​or subranges covered within the range, as if each numerical value and subrange were explicitly stated. For example, the range “about 0.1% to about 5%” or “about 0.1% to 5%” should be understood to include not only about 0.1% to about 5% but also the individual values ​​within the range shown (e.g., 1%, 2%, 3%, and 4%) and subranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, 3.3% to 4.4%). Unless otherwise specified, the expression “about X to Y” has the same meaning as “about X to about Y”. Similarly, unless otherwise specified, the statement “about X, Y, or about Z” has the same meaning as “about X, about Y, or about Z”.

[0024] In this document, unless the context clearly specifies otherwise, the terms “a,” “an,” or “the” are used to include one or more. Unless otherwise specified, the term “or” is used to mean a non-exclusive “or.” The statements “at least one of A and B” or “at least one of A or B” have the same meaning as “A, B, or A and B.” Furthermore, it should be understood that phrases or terms used herein without further definition are for descriptive purposes only and not for limiting purposes. Any use of section headings is intended to aid reading the document and should not be construed as restrictive; information relating to a section heading may appear within or outside the specific section in question.

[0025] In the methods described herein, actions may be performed in the specific order described herein. Additionally, in any aspect disclosed herein, except where the timing or sequence of operations is explicitly stated, specific actions may be performed in any order without departing from the principles of this disclosure. Furthermore, specified actions may be performed simultaneously unless the explicit language of the claims states that they are performed individually or the ordinary meaning of the claims would require it. For example, the claimed action of doing X and the claimed action of doing Y may be performed simultaneously within a single operation, and the resulting process will fall within the literal scope of the claimed process.

[0026] As used herein, the term "and / or" means any of the possibilities or combinations thereof stated in the alternatives. For example, "A, B and / or C" means A, B, C or a combination thereof.

[0027] As used herein, the term “about” may allow for a degree of variability in a value or range, for example, within 10%, 5%, or 1% of the stated value or range limits, and includes the exact stated value or range.

[0028] As used herein, the term “substantially” means the majority or most, such as at least about 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about 99.999% or more, or 100%. As used herein, the term “substantially free” can mean not having or having a negligible amount of material such that the amount of material present does not affect the material properties of the composition comprising the material, such that about 0 wt% to about 0.1 wt% of the composition is the material, or about 0 wt% to about 0.01 wt%, or about 0.1 wt% or less, or less than, equal to or greater than about 0.9 wt%, 0.8 wt%, 0.7 wt%, 0.6 wt%, 0.5 wt%, 0.4 wt%, 0.3 wt%, 0.2 wt%, 0.1 wt%, 0.08 wt%, 0.06 wt%, 0.04 wt%, 0.02 wt%, 0.01 wt%, or about 0.001 wt% or less, or about 0 wt%.

[0029] Conductive porous substrate.

[0030] Various aspects of this disclosure provide a porous substrate. Figure 1An example of a porous substrate 100 having a honeycomb form is shown. For example, the honeycomb form can be achieved by extruding a mixture (which may be referred to as a batch mixture) through a corresponding honeycomb extrusion die. After extrusion, the green body can be dried and / or fired. For example, firing can be used to react the ceramic precursor particles into one or more ceramic phases, and / or to sinter the particles together to form a glassy and / or ceramic phase.

[0031] like Figure 1 As shown, a substrate 100 extends in an axial direction 105 between a first end face 101 and a second end face 103. The substrate 100 includes a plurality of porous walls 102 made of a ceramic and / or glass material further described herein. The porous walls 102 are arranged in an intersecting array and define a plurality of channels 104 extending axially through the substrate 100. Thus, the first end 101 can receive a fluid flow, such as a flow containing carbon dioxide (if used in a carbon capture system) or an exhaust gas flow (if used with a catalytic conversion system), and the fluid flow travels through the channels 104 through the substrate 100 and exits from the second end 103. Figure 1 In one example, the cross-section of channel 104 of base 100 is square. However, in other examples, channel 104 can be of different shapes, such as hexagonal, triangular, or some other shape.

[0032] exist Figure 1 In this example, substrate 100 is depicted as substantially cylindrical (with a circular cross-section). However, in other examples, substrate 100 can be any suitable shape. For example, substrate 100 can be shaped as a rectangular block to facilitate stacking into an array suitable for large-scale carbon dioxide capture systems. The cross-sectional shape can be defined relative to one or more lateral directions. That is, a lateral direction refers to a direction perpendicular to the axial direction. Therefore, a lateral direction can be defined as any direction perpendicular to the axial direction. For example, Figure 1 The horizontal direction 107 is marked in the middle, which corresponds to the radial direction of the drawn cylinder shape.

[0033] The porous substrate may include a continuous graphite phase. The porous substrate may also include a glassy and / or ceramic phase. The graphite phase and the glassy and / or ceramic phase may together form a continuous, interconnected porous structure. The total pore volume of the porous substrate may be at least 40%, as determined by mercury porosimetry. The porous substrate is electrically conductive. For example, mercury porosimetry for determining the total pore volume can be performed according to ASTM D6761-07 (2012).

[0034] The continuity of the graphite phase in a porous substrate enables or promotes the electrical conductivity of the substrate, and the connected and interwoven ceramic and / or glassy phases can provide mechanical strength to the porous substrate. By maintaining continuity throughout the porous substrate, the graphite phase advantageously achieves conductivity in both axial and transverse (e.g., radial) directions, which facilitates various electrode attachment orientations. The transverse direction refers to the direction perpendicular to the axial direction, i.e., the direction that crosses opposite sides of the substrate when viewed in cross-section, such as the radial direction. For example, a continuous graphite phase allows a pair of electrodes to be connected at or near opposite axial ends, such that current travels axially downwards along the length of the substrate, and / or allows the pair of electrodes to be connected at different peripheral sides of the substrate, such that current travels transversely (e.g., radially) across the substrate in a direction perpendicular to the axial direction. Therefore, a continuous graphite phase enables current to travel axially downwards along the length of the substrate, as well as transversely across the substrate.

[0035] In various respects, the glass and / or ceramic phase can also be a continuous phase in the porous substrate. The graphite phase, the glass and / or ceramic phase, or both, can be uniformly distributed in the porous substrate. The continuous graphite phase can be uniformly distributed in the glass and / or ceramic phase (e.g., the graphite phase exists in a three-dimensional form within and throughout the glass and / or ceramic phase, and not merely as a surface coating on the glass and / or ceramic phase).

[0036] Porous substrates can have any suitable packing density. Packing density is the mass of the substrate divided by the total volume occupied by the substrate, which includes particle volume, interparticle void volume, and internal pore volume (intergranular voids), but excludes longitudinal channels (e.g., the portion of the substrate considered as open front area when viewed from the longitudinal end). The total volume occupied by a substrate with a honeycomb structure can be defined as the portion of the substrate considered as closed front area (CFA) when viewed from the longitudinal end, as opposed to the portion of open front area (OFA), where CFA and OFA are given as complementary percentages totaling 100%. Specifically, OFA corresponds to the portion of the cross-sectional area occupied by the open channels of the honeycomb-shaped substrate, while CFA corresponds to the remaining portion occupied by the intersecting walls of the matrix. For example, the packing density of a porous substrate can be less than 1.5 g / cm³. 3 Or at 0.5 g / cm 3 Up to 1.15 g / cm 3 0.6 g / cm 3 Up to 0.8 g / cm 3 Within the range, or less than or equal to 1.5 g / cm³ 3 And greater than or equal to 0.5 g / cm 3 And less than, equal to or greater than 0.6 g / cm³ 3 0.7 g / cm3 0.8 g / cm 3 0.9 g / cm 3 1 g / cm 3 1.1 g / cm 3 1.2 g / cm 3 1.3 g / cm 3 Or 1.4 g / cm 3 The porous substrate may have any suitable total pore volume (e.g., measured without any coating added to the porous substrate), determined by mercury porosimetry, for example, greater than 40%, or in the range of 40% to 95%, 50% to 95%, or less than or equal to 95% and greater than or equal to 40%, and less than, equal to, or greater than 42%, 44%, 46%, 48%, 50%, 52%, 54%, 56%, 58%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88%, 90%, 92%, or 94%.

[0037] The conductive porous substrate can have any suitable resistance, such as 1 ohm to 1000 ohms, 1 ohm to 100 ohms, or less than or equal to 1000 ohms and greater than or equal to 1 ohm, and less than, equal to, or greater than 2 ohms, 3 ohms, 4 ohms, 5 ohms, 6 ohms, 8 ohms, 10 ohms, 15 ohms, 20 ohms, 25 ohms, 30 ohms, 40 ohms, 50 ohms, 75 ohms, 100 ohms, 150 ohms, 200 ohms, 250 ohms, 300 ohms, 400 ohms, 500 ohms, 600 ohms, 700 ohms, 800 ohms, 900 ohms, or 950 ohms. The resistance can be measured from one end of the porous substrate to the opposite end, or from one end along the longitudinal axis of the porous substrate to the opposite end along the longitudinal axis.

[0038] Porous substrates can have any suitable physical form. In various aspects, the physical form is a honeycomb form, such as an extruded honeycomb form, containing multiple compartments that define parallel channels extending longitudinally through the honeycomb form. The compartments can be formed from an array of intersecting walls or a matrix. The honeycomb form can have any suitable perimeter profile or shape, such as circular, elliptical, square, rectangular, hexagonal, triangular, polygonal, or irregular shapes. When viewed from one end of the honeycomb form, the compartments can have any suitable shape, such as circular, elliptical, square, rectangular, hexagonal, triangular, polygonal, or irregular shapes. For example, one possible combination is a cylindrical substrate with square compartments (circular perimeter profile). Compared to other forms (e.g., filled granular beds), using a honeycomb form can advantageously reduce the pressure drop of the fluid flow from one axial end of the bulk material to the other. Cellular configurations may include any suitable number of cells per square inch (e.g., as measured when viewed from one end), such as 20 to 1000 cells or 50 to 600 cells per square inch, or less than or equal to 1000 cells per square inch and greater than or equal to 20 square inches, and less than, equal to, or greater than 40 square inches, 60 cells, 80 cells, 100 cells, 120 cells, 140 cells, 160 cells, etc. 180 compartments, 200 compartments, 220 compartments, 240 compartments, 260 compartments, 280 compartments, 300 compartments, 320 compartments, 340 compartments, 360 compartments, 400 compartments, 450 compartments, 500 compartments, 550 compartments, 600 compartments, 650 compartments, 700 compartments, 750 compartments, 800 compartments, 850 compartments, 900 compartments, or 950 compartments. The compartments in the cellular form have any suitable wall thickness, such as 0.001 inches to 0.1 inches, or 0.002 inches to 0.05 inches, or less than or equal to 0.1 inches and greater than or equal to 0.001 inches, and less than, equal to or greater than 0.002 inches, 0.003 inches, 0.004 inches, 0.005 inches, 0.006 inches, 0.007 inches, 0.008 inches, 0.009 inches, 0.01 inches, 0.011 inches, 0.012 inches, 0.013 inches, 0.014 inches, 0.015 inches, 0.016 inches, 0.017 inches, 0.018 inches, 0.019 inches, 0.02 inches, 0.025 inches, 0.03 inches, 0.035 inches, 0.04 inches, or 0.045 inches. In various aspects, the cells in a cellular form can include a geometry of 100 / 8 or 200 / 8 cells per square inch / 0.001 inch wall thickness.The diameter of the honeycomb pattern can be 3 inches to 15 inches, or less than or equal to 15 inches and greater than or equal to 3 inches, and less than, equal to, or greater than 4 inches, 5 inches, 6 inches, 7 inches, 8 inches, 9 inches, 10 inches, 11 inches, 12 inches, 13 inches, or 14 inches. The length of the honeycomb pattern can be 3 inches to 15 inches, or less than or equal to 15 inches and greater than or equal to 3 inches, and less than, equal to, or greater than 4 inches, 5 inches, 6 inches, 7 inches, 8 inches, 9 inches, 10 inches, 11 inches, 12 inches, 13 inches, or 14 inches.

[0039] Porous substrates can have any suitable open front area. The open front area (OFA) is the percentage of the cross-sectional area of ​​the longitudinal channels in a honeycomb configuration, through which, for example, gas can flow. In contrast, the closed front area (CFA) is the percentage of the cross-sectional area (perpendicular to the axial or longitudinal direction) of the intersecting walls of the substrate (i.e., excluding the open front area). For example, the open front area of ​​a porous substrate can be 60%–90%, 70%–80%, or less than 90% and greater than or equal to 60%, and less than, equal to, or greater than 61%, 62%, 64%, 66%, 68%, 70%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88%, or 89%.

[0040] In embodiments, the graphite phase comprises one or more carbonaceous materials resulting from the manufacture of the porous substrate. For example, graphite particles may be included in a batch mixture along with inorganic precursor particles (for forming glassy and / or ceramic phases), then extruded, optionally dried, and sintered. Thus, at least some of the original graphite particles may be transformed into one or more other carbonaceous materials during the manufacturing process. For example, a high-temperature sintering process may transform some graphite particles into activated carbon, charcoal, or another carbonaceous material. As used herein, the term graphite phase refers not only to graphite particles but also to a combination of other carbonaceous materials (e.g., activated carbon, charcoal, etc.) formed or formed from graphite or other batch mixture materials during the manufacture of the porous substrate. The graphite phase may include (a) graphite particles; or (b) extrusion and sintering products of graphite particles (e.g., sintered products); or a combination of (a) and (b). The graphite phase may include (a) graphite plates, graphite sheets, natural graphite, synthetic graphite, or combinations thereof; or (b) extruded and / or sintered products (e.g., sintered products) of graphite plates, graphite sheets, natural graphite, synthetic graphite, or combinations thereof; or a combination of (a) and (b). The graphite phase may include graphite particles having an elongated shape and / or a planar shape with a height less than its length and width, or the graphite phase may include extruded and sintered products of such graphite particles, or combinations thereof. Most (e.g., greater than 50%, 60%, 70%, 80%, or greater than 90%) of the graphite particles (e.g., in extruded extrudable compositions, products of extruded compositions, extruded / sintered products of extrudable compositions, or combinations thereof) may have a longitudinal axis and / or an axis orthogonal to its height (e.g., an axis parallel to and passing through a planar basal surface, such as the basal surface of a graphite plate or sheet), oriented in the same direction, e.g., in extrusion... Alignment can be within 45° in the direction of extrusion, within 30° in the direction of extrusion, or within 1°, 2°, 3°, 4°, 5°, 6°, 8°, 10°, 12°, 14°, 16°, 18°, 20°, 22°, 24°, 26°, 28°, 30°, 32°, 34°, 36°, 38°, 40°, 41°, 42°, 43°, or 44° in the direction of extrusion. In various aspects, X-ray diffraction (XRD) can be used to measure the preferred orientation of the basal plane of graphite particles, for example by performing XRD on the extruded wall of a porous substrate and comparing the intensity ratio of the 00l plane to, for example, the direction perpendicular to h00, and then comparing the intensity ratio with a powder mixture having a random orientation of the basal plane of graphite particles.

[0041] In various respects, the alignment / orientation of graphite particles in the extrusion direction of the porous substrate can make the electrical conductivity of the porous substrate along the compartment walls of the substrate higher than that through the compartment walls. The electrical conductivity along the compartment walls can be 1.1-10 times, or 3-5 times, or less than or equal to 10 times and greater than or equal to 1.1 times, and less than, equal to, or greater than 1.2, 1.3, 1.4, 1.5, 1.6, 1.8, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 7, 8, or 9 times that in the direction through the compartment walls. Accordingly, the thermal conductivity along the compartment wall can be 1.1-10 times, or 3-5 times, or less than or equal to 10 times and greater than or equal to 1.1 times, and less than, equal to or greater than 1.2, 1.3, 1.4, 1.5, 1.6, 1.8, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 7, 8 or 9 times that of the thermal conductivity through the compartment wall.

[0042] The graphite phase can be any suitable proportion of the porous substrate. For example, the graphite phase can comprise 2 wt% to 30 wt%, 5 wt% to 20 wt%, 7 wt% to 19 wt% of the porous substrate, or less than or equal to 30 wt% and greater than or equal to 2 wt%, and less than, equal to, or greater than 4 wt%, 6 wt%, 8 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, or 28 wt%.

[0043] The glass and / or ceramic phase can constitute any suitable proportion of the porous substrate. For example, the glass and / or ceramic phase can constitute 10 wt% to 70 wt%, 15 wt% to 60 wt%, 20 wt% to 55 wt% of the porous substrate, or less than or equal to 70 wt% and greater than or equal to 10 wt%, and less than, equal to, or greater than 12 wt%, 14 wt%, 16 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, 28 wt%, 30 wt%, 32 wt%, 34 wt%, 36 wt%, 38 wt%, 40 wt%, 42 wt%, 44 wt%, 46 wt%, 48 wt%, 50 wt%, 52 wt%, 54 wt%, 56 wt%, 58 wt%, 60 wt%, 62 wt%, 64 wt%, 66 wt%, or 68 wt%.

[0044] In various aspects, the porous substrate may further include hollow and / or porous materials. Hollow and / or porous materials may include paper, polymers, glass, glass ceramics, ceramics, diatomaceous earth, or combinations thereof. Hollow and / or porous materials may include hollow glass beads. Hollow and / or porous materials may constitute any suitable proportion of the porous substrate, for example, 10 wt% to 60 wt%, or 20 wt% to 50 wt%, or 25 wt% to 45 wt%, or less than or equal to 60 wt% and greater than or equal to 10 wt%, and less than, equal to or greater than 12 wt%, 14 wt%, 16 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, 28 wt%, 30 wt%, 32 wt%, 34 wt%, 36 wt%, 38 wt%, 40 wt%, 42 wt%, 44 wt%, 46 wt%, 48 wt%, 50 wt%, 52 wt%, 54 wt%, 56 wt%, or 58 wt%.

[0045] In a four-point bending test of porous substrates, for example, according to ASTM-D6272, the porous substrate can have any suitable flexural strength. For ease of comparison of monolithic honeycomb materials with different geometries, the strength can be normalized using the CFA of the porous substrate. For example, in a four-point bending test of a porous substrate, the flexural strength of the porous substrate normalized by the CFA of the porous substrate (i.e., divided by the CFA of the porous substrate, given as a percentage) can be greater than 500 psi, or in the range of 500 psi to 2500 psi or 1000 psi to 2500 psi, or less than or equal to 3000 psi and greater than or equal to 500 psi, and less than, equal to or greater than 600 psi, 700 psi, 800 psi, 900 psi, 1000 psi, 1100 psi, 1200 psi, 1300 psi, 1400 psi, 1500 psi, 1600 psi, 1700 psi, 1800 psi, 1900 psi, 2000 psi, 2100 psi, 2200 psi, 2300 psi or 2400 psi.

[0046] Quadrilateral quartz may comprise 30 wt% or less of the porous substrate, or 10 wt% or less of the porous substrate, for example, 0 wt% to 29 wt%, or 0 wt% to 9.9 wt%, or less than or equal to 29 wt% and greater than or equal to 0 wt%, and less than, equal to or greater than 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 12 wt%, 14 wt%, 16 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, or 28 wt%.

[0047] The porous substrate may optionally include a coating. The coating may comprise any suitable material, such as an adsorbent (e.g., an adsorbent for adsorbing and desorbing CO2), a catalyst (e.g., a catalyst for treating exhaust emissions in a catalytic converter, or another catalyst), or some other active or functional material involved in the capture, trapping, adsorption, absorption, reaction, treatment, elimination, or conversion of one or more selected compounds (e.g., pollutants to be removed or compounds to be harvested). Many materials may require a certain temperature to become active. For example, some catalysts may only function above a threshold "light-off" temperature, while some adsorbents may require a certain temperature to desorb carbon dioxide in a carbon capture cycle. Advantageously, the electrical conductivity of the porous substrate described herein allows for direct control of the substrate temperature by passing an electric current through the substrate, enabling efficient control of catalysts, adsorbents, or other temperature-dependent active materials.

[0048] In various aspects, the coating can adhere directly to a porous substrate, wherein the porous substrate does not contain an intermediate binder layer between the coating and the glass and / or ceramic phase. However, in various aspects, the porous substrate may include a binder layer. The binder layer can be any suitable binder layer. The binder layer can be a carrier coating material. The binder layer may include a deposition of high surface area particles, such as γ-alumina, zeolite, activated carbon, or combinations thereof. Coatings including adsorbents can be adsorbents, or may include one or more other components. The adsorbent can be any suitable adsorbent for adsorbing and desorbing CO2, such as zeolite, sodium carbonate, activated carbon, carbon nanotubes, metal-organic frameworks (MOFs), amines, or combinations thereof. Porous substrates including coatings containing adsorbents and / or catalysts may include any suitable loading level of adsorbent or catalyst, such as 0.1 wt% to 99% wt% (e.g., 0.1 wt% to 99 wt% of the porous substrate including the coating is adsorbent or catalyst), 1 wt% to 90 wt%, or less than or equal to 99% wt% and greater than or equal to 0.1 wt%, and less than, equal to, or greater than 1 wt%, 2 wt%, 4 wt%, 6 wt%, 8 wt%, 10 wt%, 12 wt%, 16 wt%, 18 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 82 wt%, 84 wt%, 86 wt%, 88 wt%, 90 wt%, 91 wt%, 92 wt%, 93 wt%. wt%, 94 wt%, 95 wt%, 96 wt%, 97 wt% or 98 wt%.

[0049] The porous substrate can be an extruded and sintered product of an extrudable composition. An extrudable composition (which may also be referred to as a batch, batch mixture, or batch composition) may include a binder and / or sintering aid. An extrudable composition may also include graphite particles. An extrudable composition can be an extrudable paste containing the foregoing components as well as a liquid component, such as water, and oil, fatty acids, or other extrusion aids or lubricants.

[0050] The binder and / or sintering aid can be any suitable proportion of the extrudable composition. For example, based on the dry weight of the extrudable composition, the binder and / or sintering aid can account for 10 wt% to 70 wt%, or 15 wt% to 60 wt%, or 20 wt% to 55 wt%, or less than or equal to 70 wt% and greater than or equal to 10 wt%, or less than, equal to, or greater than 12 wt%, 14 wt%, 16 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, 28 wt%, 30 wt%, 32 wt%, 34 wt%, 36 wt%, 38 wt%, 40 wt%, 42 wt%, 44 wt%, 46 wt%, 48 wt%, 50 wt%, 52 wt%, 54 wt%, 56 wt%, 58 wt%, 60 wt%, 62 wt%, 64 wt%, 66 wt%, or 68 wt%. Binders and / or sintering aids may include inorganic binders, polymers, thermosetting resins, carbon precursors, borates, phosphates, transition metal oxides, oxides, hydroxides, carbonates, silicates, aluminosilicates, cellulose derivatives, or combinations thereof. Cellulose derivatives may include (C1-C3)alkylhydroxy(C1-C3)alkylcellulose, or (C1-C3)alkylhydroxycellulose, or (C1-C3)alkylcellulose, or (C1-C3)alkyl(C1-C3)alkylcellulose, or methylhydroxypropylcellulose, methylhydroxyethylcellulose, methylhydroxymethylcellulose, methylcellulose, ethylcellulose, propylcellulose, hydroxypropylcellulose, methylethylcellulose, sodium carboxymethylcellulose, or combinations thereof.

[0051] Graphite particles may include graphite plates, graphite sheets, natural graphite, synthetic graphite, or combinations thereof. Graphite particles may include elongated shapes and / or planar shapes with a height less than their length and width. The median longest dimension (e.g., diameter) of the graphite particles may be 1 micrometer to 100 micrometers, 5 micrometers to 15 micrometers, or less than or equal to 1 micrometer and greater than or equal to 100 micrometers, or less than, equal to, or greater than 2 micrometers, 3 micrometers, 4 micrometers, 5 micrometers, 6 micrometers, 7 micrometers, 8 micrometers, 9 micrometers, 10 micrometers, 11 micrometers, 12 micrometers, 13 micrometers, 14 micrometers, 15 micrometers, 16 micrometers, 17 micrometers, 18 micrometers, 19 micrometers, 20 micrometers, 22 micrometers, 24 micrometers, 26 micrometers, 28 micrometers, 30 micrometers, 35 micrometers, 40 micrometers, 45 micrometers, 50 micrometers, 60 micrometers, 70 micrometers, 80 micrometers, or 90 micrometers. The aspect ratio (e.g., thickness to diameter) of the graphite particles can be from 1:2 to 1:100, or from 1:5 to 1:15, or less than or equal to 1:2 and greater than or equal to 1:100, and less than, equal to, or greater than 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19, 1:20, 1:25, 1:30, 1:35, 1:40, 1:45, 1:50, 1:60, 1:70, 1:80, or 1:90. The graphite particles can constitute any suitable proportion of the extrudable composition. For example, on a dry weight basis, graphite particles may comprise 2 wt% to 30 wt%, 5 wt% to 20 wt%, 7 wt% to 19 wt% of the extrudable composition, or less than or equal to 30 wt% and greater than or equal to 2 wt%, or less than, equal to, or greater than 4 wt%, 6 wt%, 8 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, or 28 wt%.

[0052] The extrudable composition may further comprise one or more solvents, such as aqueous solvents or organic solvents. The solvent may be water or include water. The solvent may constitute any suitable proportion of the extrudable composition, for example, 5 wt% to 60 wt%, or 10 wt% to 40 wt%, or less than or equal to 60 wt% and greater than or equal to 5 wt%, and less than, equal to, or greater than 6 wt%, 8 wt%, 10 wt%, 12 wt%, 14 wt%, 16 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, 28 wt%, 30 wt%, 32 wt%, 34 wt%, 36 wt%, 38 wt%, 40 wt%, 42 wt%, 44 wt%, 46 wt%, 48 wt%, 50 wt%, 52 wt%, 54 wt%, 56 wt%, or 58 wt%.

[0053] Extrudable compositions may include any suitable one or more optional components. For example, extrudable compositions may further include surfactants (e.g., sodium stearate), lubricants (e.g., lubricating oils), or combinations thereof. One or more optional components may constitute any suitable proportion of the extrudable composition, on a dry weight basis, for example, 0 wt% to 30 wt%, 0 wt% to 10 wt%, or 1 wt% to 5 wt%, or less than or equal to 10 wt% and greater than or equal to 0 wt%, and less than, equal to, or greater than 0.1 wt%, 0.5 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 12 wt%, 14 wt%, 16 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, or 28 wt%.

[0054] In various aspects, the extrudable composition may further comprise hollow and / or porous materials. Hollow and / or porous materials may include paper, polymers, glass, glass-ceramics, ceramics, diatomaceous earth, or combinations thereof. Hollow and / or porous materials may include hollow glass beads. Hollow and / or porous materials may constitute any suitable proportion of the extrudable composition. For example, on a dry weight basis, hollow and / or porous materials may comprise 10 wt% to 60 wt%, 20 wt% to 50 wt%, 25 wt% to 45 wt% of the extrudable composition, or less than or equal to 60 wt% and greater than or equal to 10 wt%, or less than, equal to, or greater than 12 wt%, 14 wt%, 16 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, 28 wt%, 30 wt%, 32 wt%, 34 wt%, 36 wt%, 38 wt%, 40 wt%, 42 wt%, 44 wt%, 46 wt%, 48 wt%, 50 wt%, 52 wt%, 54 wt%, 56 wt%, or 58 wt%.

[0055] In various aspects, the extrudable composition further includes a pore-forming material, wherein the pore-forming material degrades and / or pyrolyzes (e.g., burns off) during firing to form pores in a porous substrate. The pore-forming material can be any suitable pore-forming material, such as starch (e.g., cross-linked starch, such as cross-linked pea starch), nut shell powder, carbon, natural polymers, synthetic polymers, carbonaceous materials, crystalline carbon, amorphous carbon, or combinations thereof. The pore-forming material can constitute any suitable proportion of the extrudable composition. For example, on a dry weight basis, the pore-forming material may comprise 5 wt% to 50 wt%, 10 wt% to 30 wt%, 14 wt% to 27 wt% of the extrudable composition, or less than or equal to 50 wt% and greater than or equal to 5 wt%, or less than, equal to, or greater than 6 wt%, 8 wt%, 10 wt%, 12 wt%, 14 wt%, 16 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, 28 wt%, 30 wt%, 32 wt%, 34 wt%, 36 wt%, 38 wt%, 40 wt%, 42 wt%, 44 wt%, 46 wt%, or 48 wt%.

[0056] A method for forming a conductive porous substrate.

[0057] Various aspects of this disclosure provide a method for forming the conductive porous substrate described herein. Figure 2An example is illustrated below. In this example, the method includes extruding an extrudable composition 10 via an extruder 20, which may alternatively be referred to as a batch or batch mixture. For example, the extruder 20 may include a honeycomb extrusion die to shape the extrudable composition 10 into a honeycomb form. Thus, in Figure 2 In one example, the extruder has reference numeral 100G, indicating that it is a substrate 100 in a green (fired) state. The method optionally includes drying the extruded composition (e.g., unfired green substrate 100G). The method also includes firing the extruded composition (e.g., unfired green substrate 100G) via a furnace (or kiln) 30 to form a porous substrate 100.

[0058] Optional drying steps can be any suitable drying process that substantially removes the solvent from the extruded composition. Drying may include heating, airflow, and / or exposure to microwaves or other energy sources. Drying may include placing the extruded composition under a vacuum. Drying may include drying at a sufficient temperature and for a sufficient duration to substantially remove all solvent from the extruded composition (e.g., such that the solvent content of the dried composition is less than 5 wt%, or less than 2 wt%, less than 1 wt%, less than 0.5 wt%, or less than 0.1 wt%).

[0059] Firing may include firing at the following firing soak temperatures: 600°C to 1100°C, or 650°C to 950°C, or less than or equal to 1100°C and greater than or equal to 600°C, and less than, equal to, or greater than 650°C, 700°C, 750°C, 800°C, 850°C, 900°C, 950°C, 1000°C, or 1050°C. The firing soak temperature may be sufficient to cause the binder and / or sintering aids to react and / or sinter. Firing may include firing duration (e.g., maintaining the firing soak temperature) of 1 hour to 24 hours, 2 hours to 6 hours, or less than or equal to 24 hours and greater than or equal to 1 hour, and less than, equal to, or greater than 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 8 hours, 10 hours, 12 hours, 14 hours, 16 hours, 18 hours, 20 hours, or 22 hours. Firing may involve ramping the temperature of the extruded composition to a homogenizing temperature at rates ranging from 10°C / hour to 100°C / hour, or from 30°C / hour to 70°C / hour, or less than or equal to 100°C / hour and greater than or equal to 10°C / hour, and less than, equal to, or greater than 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, or 95°C. Firing may be carried out in an atmosphere containing an oxygen concentration sufficiently low to prevent oxidation of the graphene particles during firing. For example, firing may be carried out under an inert gas such as nitrogen or argon. Firing may be carried out in the presence of an oxygen-absorbing material such as an oxygen getter. By limiting the amount of oxygen during firing, oxidation of the graphite particles can be reduced or eliminated.

[0060] The shrinkage of the porous substrate compared to the extruded composition can be 0% to 15%, 2% to 7%, or less than or equal to 15% and greater than or equal to 0%, and less than, equal to, or greater than 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, or 14%. Shrinkage can be a change in diameter from the extruded product to the final sintered product (e.g., linear shrinkage).

[0061] Firing may include firing the extruded composition in any suitable type of furnace (kiln) having any suitable temperature distribution. In various aspects, firing may include firing the extruded composition in a furnace that includes an unheated insert portion. The furnace may include a heated central portion maintained at temperatures of about 920°C to 1000°C, about 930°C to about 970°C, or less than or equal to 1000°C and greater than or equal to 920°C, and less than, equal to, or greater than 925°C, 930°C, 935°C, 940°C, 945°C, 950°C, 955°C, 960°C, 965°C, 970°C, 975°C, 980°C, 985°C, 990°C, or 995°C. The furnace may also include an unheated outlet portion. The method may include maintaining the extruded composition at a preheating distance from the furnace inlet or from the inlet of the unheated insert portion for a preheating duration before inserting the extruded composition into the furnace. The preheating distance can be 0.01 m to 0.1 m, or less than or equal to 0.1 m and greater than or equal to 0.01 m, and less than, equal to, or greater than 0.02 m, 0.03 m, 0.04 m, 0.05 m, 0.06 m, 0.07 m, 0.08 m, or 0.09 m. The preheating duration can be 1 minute to 10 minutes, or less than or equal to 10 minutes and greater than or equal to 1 minute, and less than, equal to, or greater than 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, or 9 minutes. The distance from the inlet of the unheated insert portion to the outlet of the unheated outlet portion can be the total length (L) of the furnace, wherein the method includes moving the extruded composition through the furnace at a rate of about 0.01*L per minute to 0.1*L per minute, further including holding the extruded composition stationary in the heated central portion for a heating duration of 5 minutes to 1 hour. The heating rate can be from 0.01 L / min to 0.1 L / min or from 0.03 L / min to 0.07 L / min, or less than or equal to 0.1 L / min and greater than or equal to 0.01 L / min, and less than, equal to, or greater than 0.02 L / min, 0.03 L / min, 0.04 L / min, 0.05 L / min, 0.06 L / min, 0.07 L / min, 0.08 L / min, or 0.09 L / min. The heating duration can be from 5 minutes to 1 hour, or from 10 minutes to 30 minutes, or less than or equal to 1 hour and greater than or equal to 5 minutes, and less than, equal to, or greater than 10 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, or 55 minutes. Firing can be completed within the following durations: 20 minutes to 2 hours, or 30 minutes to 1 hour, or less than or equal to 2 hours and greater than or equal to 20 minutes, and less than, equal to, or greater than 30 minutes, 40 minutes, 50 minutes, 60 minutes, 70 minutes, 80 minutes, 90 minutes, 100 minutes, or 110 minutes. Extrudable compositions may include hollow glass beads.

[0062] A method for forming a porous substrate in a furnace that includes an insertion section, a central section, and an outlet section.

[0063] Various aspects of this disclosure provide a method for forming a porous substrate. The porous substrate may be a conductive porous substrate as described herein, or another porous substrate (e.g., a non-conductive porous substrate). The method may include extruding an extrudable composition comprising a binder and / or a sintering aid. The method may include drying the extruded composition. The method may also include firing the extruded composition to form a porous substrate. Firing may include firing the extruded composition in a furnace including an unheated insert portion. The furnace may include a heated central portion maintained at temperatures of about 920°C to 1000°C, about 930°C to about 970°C, or less than or equal to 1000°C and greater than or equal to 920°C, and less than, equal to, or greater than 925°C, 930°C, 935°C, 940°C, 945°C, 950°C, 955°C, 960°C, 965°C, 970°C, 975°C, 980°C, 985°C, 990°C, or 995°C. The furnace may also include an unheated outlet portion. The method may include maintaining the extruded composition at a preheating distance from the furnace inlet or from the inlet of an unheated insertion portion for a preheating duration before inserting the extruded composition into the furnace. The preheating distance may be 0.01 m to 0.1 m, or less than or equal to 0.1 m and greater than or equal to 0.01 m, and less than, equal to, or greater than 0.02 m, 0.03 m, 0.04 m, 0.05 m, 0.06 m, 0.07 m, 0.08 m, or 0.09 m. The preheating duration may be 1 minute to 10 minutes, or less than or equal to 10 minutes and greater than or equal to 1 minute, and less than, equal to, or greater than 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, or 9 minutes. The distance from the inlet of the unheated insert portion to the outlet of the unheated outlet portion can be the total length (L) of the furnace, wherein the method includes moving the extruded composition through the furnace at a rate of about 0.01 L per minute to 0.1 L per minute, further including holding the extruded composition stationary in the heated central portion for a heating duration of 5 minutes to 1 hour. The rate can be from 0.01 L per minute to 0.1 L per minute or from 0.03 L to 0.07 L per minute, or less than or equal to 0.1 L per minute and greater than or equal to 0.01 L per minute, and less than, equal to, or greater than 0.02 L per minute, 0.03 L per minute, 0.04 L per minute, 0.05 L per minute, 0.06 L per minute, 0.07 L per minute, 0.08 L per minute, or 0.09 L per minute. The heating duration can be from 5 minutes to 1 hour, or from 10 minutes to 30 minutes, or less than or equal to 1 hour and greater than or equal to 5 minutes, and less than, equal to or greater than 10 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes or 55 minutes.Firing can be completed within the following durations: 20 minutes to 2 hours, or 30 minutes to 1 hour, or less than or equal to 2 hours and greater than or equal to 20 minutes, and less than, equal to, or greater than 30 minutes, 40 minutes, 50 minutes, 60 minutes, 70 minutes, 80 minutes, 90 minutes, 100 minutes, or 110 minutes. Extrudable compositions may include hollow glass beads.

[0064] Methods using porous substrates.

[0065] Various aspects of this disclosure provide a method of using a conductive porous substrate of this disclosure, the conductive porous substrate comprising a coating comprising an adsorbent capable of adsorbing and desorbing CO2. The coating may be continuous or discontinuous. The method may include exposing the porous substrate to an airflow comprising CO2 to at least partially adsorb CO2 from the airflow. The method may also include desorbing CO2 from the coating on the porous substrate. In various aspects, desorbing CO2 from the coating on the porous substrate includes heating the porous substrate, for example via resistance heating, delivering hot gas (e.g., steam) to the porous substrate, microwave heating, induction heating, via an external heat source surrounding the porous substrate, or a combination thereof. In various aspects, desorbing CO2 from the coating may include encapsulating the CO2, for example placing the CO2 in a storage tank.

[0066] The methods using the porous substrates described herein can be applied to any suitable CO2 removal method, such as direct air capture (DAC) or capturing CO2 at the effluent source. The porous substrates described herein are capable of withstanding temperatures of 200°C or higher and humid environments.

[0067] Various aspects of this disclosure provide a method for using a conductive porous substrate of this disclosure, the conductive porous substrate comprising a coating, the coating comprising a catalyst. The method may include exposing the porous substrate to a gas stream to catalyze a chemical reaction of one or more components in the gas stream using the catalyst.

[0068] Example

[0069] Various aspects of this disclosure can be better understood by referring to the following examples provided with the aid of illustrations. This disclosure is not limited to the examples given herein. The mercury orifice test is performed according to ASTM D6761-07 (2012). The term "bulk" is interchangeably referred to as bulk, component, or sample in the description of the embodiments.

[0070] Figure 3A and 3B The image shows SEM images of representative example substrates with glassy and / or ceramic phases and continuous graphite phases. Specifically, Figure 3A and 3BThe substrate is made of a mixture comprising hollow glass microspheres (HGMS), clay, talc, starch pore-forming agent, and graphite powder, which is extruded into a honeycomb shape and fired. Figure 3A and 3B In this design, the structural portions created by HGMS particles can be identified as circular or annular white areas, one of which is marked with reference numeral 110. In contrast, large, black and dark gray circular or elliptical areas of similar size (one of which is marked with reference numeral 114) indicate pores (voids) and char left by starch pore-forming agent particles that have burned off or combusted during firing. The relatively small size of the talc, clay, and graphite particles used allows these materials to aggregate in the gaps between the HGMS particles and the pore-forming agent particles (before combustion during firing), indicated by reference numeral 112. In this way, inorganic particles (e.g., talc, clay, HGMS) sinter together and / or at least partially react to form one or more ceramic phases to produce a glassy and / or ceramic phase that acts as the “skeleton” of the substrate, while graphite particles, together with any remaining char from sintering, produce a continuous graphite phase that imparts conductivity to the substrate described herein.

[0071] Example 1-33.

[0072] The inorganic components of each composition shown in Table 1-3 were dry-mixed in a Littleford mixer, followed by the addition of water and MOx 30A (mineral oil) and an additional wet-mixing cycle. The wet powder was then transferred to a 40 mm twin-screw mixer and extruded through a 2-inch diameter die with 200 compartments (cpsi) / 8 mils or 300 cpsi and 8 mils per square inch. The parts were dried in a microwave dryer and fired in a covered crucible in a gas-fired kiln at a temperature between 650°C and 950°C for 4 hours, also as indicated in Table 1-3. A green cookie was placed on top of the parts in the crucible to act as an oxygen absorber against any air leakage between the crucible and the lid. This firing method protects the graphite from oxidation during firing.

[0073] The compositions and physical properties are shown in Tables 1-3. The first row shows the example number. The second row indicates whether the example is an example of the invention or a comparative example. The following rows show the inorganic raw materials used and their amounts in wt%. ZH C70HGMS is hollow glass microspheres. Diafil 525 is a diatomaceous earth. Graphite is graphite flakes with a median particle size of 9 micrometers and an aspect ratio of about 8-12:1. Figure 5 SEM images of graphite flakes are shown. Kaolin and flake talc particles were also used in some instances. Potassium carbonate (K₂CO₃) and boric acid were also used as sintering aids, as outlined in the table.

[0074] The organic materials and water used are shown below, with amounts given as a superaddition relative to 100 parts of inorganic matter. The pea starch is cross-linked pea starch.

[0075] Table 1-3 shows the homogenization temperatures for firing. Each composition was heated to the homogenization temperature at a rate of 50°C / hour and held at the homogenization temperature for 4 hours. Shrinkage is given as the average shrinkage from the extrusion die to the diameter of the fired part. A shrinkage of less than about 10% is expected to maintain good dimensional control throughout the process. Geometry is given as nominal compartment density (compartments / square inch or cpsi) and web thickness in mils. The bulk density of the porous material (independent of the channels in the cellular structure) was measured by mercury porosimetry. Porosity is given as vol% determined by mercury porosimetry. The median pore size (overall pore size distribution) determined by mercury porosimetry is given in micrometers. The modulus of rupture (MOR) was measured by a 4-point bending test on rectangular bars cut from the fired part according to ASTM-D6272. MOR was normalized by CFA to eliminate the influence of compartment geometry. The cristobalite concentration was measured by Rietveld XRD analysis of the fired part. Quadrilateral quartz is a material with high thermal expansion, and it also exhibits volume changes related to phase transition at approximately 200°C. Concentrations above approximately 10% have been found to cause cracking in fired parts during cooling from the homogenizer, and therefore it is desirable to minimize the concentration of this phase in the fired product. Finally, the last row shows whether the product has a suitable resistivity for supporting resistance heating and good thermal conductivity. Table 4 is the same as Table 1, Table 5 is the same as Table 2, and Table 6 is the same as Table 3, but in Tables 3-6, the amounts of material are given as wt% of the composition on a dry basis, and the firing conditions and physical properties of the resulting substrate are omitted from Tables 3-6.

[0076] Table 1. Firing composition, firing conditions and physical properties of the resulting substrate, wherein organic materials and water are given in additional amounts relative to 100 parts of inorganic matter.

[0077]

[0078]

[0079] Table 2. Firing composition, firing conditions and physical properties of the resulting substrate, wherein organic materials and water are given in additional amounts relative to 100 parts of inorganic matter.

[0080]

[0081] Table 3. Firing composition, firing conditions and physical properties of the resulting substrate, wherein organic materials and water are given in additional amounts relative to 100 parts of inorganic matter.

[0082]

[0083] Table 4. Firing composition, firing conditions and physical properties of the resulting substrate.

[0084]

[0085]

[0086] Table 5. Firing composition, firing conditions and physical properties of the resulting substrate.

[0087]

[0088] Table 6. Firing composition, firing conditions and physical properties of the resulting substrate.

[0089]

[0090] The compositions calcined in Examples 1 and 2 were mixtures of HGMS and graphite. While the resulting substrates exhibited good conductivity, they showed a problem with poor strength. The compositions calcined in Examples 3-21 and 25-33 included added (CSG) as well as boric acid and potassium carbonate as sintering aids. It can be seen that these composition modifications resulted in a significant increase in strength while maintaining good conductivity. Examples 3 to 15 are of particular interest, as they have low cristobalite content and reasonable strength when calcined at lower temperatures. Examples 19 to 27 meet most of the criteria of this invention, but their resistivity is higher than that required for these compositions. To improve in this regard, the graphite content was increased in Examples 28-33, which are currently being tested / characterized.

[0091] Example 34. Rapid sintering.

[0092] All sintering in this example was performed under a nitrogen atmosphere.

[0093] The first sintering technique involves heating the extruded, dried substrate in a box furnace from ambient temperature to 900°C at a variable rate of 400°C / hour, holding it at 900°C for two hours, and then cooling it back to ambient temperature at a rate of -400°C / hour. The first sintering technique is designed for approximately seven hours, but due to the slow cooling without forced cooling, it lasts for more than 10 hours. Even with more efficient cooling, the first sintering technique still requires approximately 7 hours.

[0094] In the second sintering technique, a tube furnace is used, comprising an unheated insert section, a heated center section, and an unheated outlet section. Each section is 14 inches long. The total length of the furnace is 42 inches. Samples are loaded into the insert section via a longitudinally running line through the furnace, the line including a carrier for holding the sample. The insert section has an open end for inserting the sample, and the outlet section is sealed with a central hole for removing the sample. The line is driven by an electric motor. In the rapid sintering technique, the tube furnace is preheated to 950°C (in the center section). Figure 4 The temperature distribution in the furnace from the open end to the starting point of the heating center is plotted. The sample was held 2 inches from the open end for 3 minutes, which helped slow the burning of the organic binder to avoid cracking. The sample was then moved to the furnace center at 2 inches per minute; held in the furnace center for 20 minutes; and then removed from the furnace at 2 inches per minute. The total cycle time was 44 minutes.

[0095] Table 7 shows two extruded compositions, each sintered using a first sintering technology and a second sintering technology.

[0096] Table 7. Extrudable compositions of Example 2.

[0097]

[0098] Both extruded compositions were 1-inch square honeycomb cells with a cell density of 300 cells per square inch and a wall thickness of 8 mils, cut into 1-inch lengths. The properties of the two extruded compositions are shown in Table 8, which demonstrates that all measured properties (including porosity, pore size, bulk density, and resistivity) of the first and second sintering technologies are very similar.

[0099] Table 8. Properties of the sintered porous substrate composition of Example 2.

[0100]

[0101] The terms and expressions used are descriptive rather than restrictive, and their use is not intended to exclude any equivalents of the features shown and described or any parts thereof, but it should be recognized that various modifications are possible within the scope of this disclosure. Therefore, it should be understood that while this disclosure includes specific aspects and optional features, modifications and variations of the concepts disclosed herein can be made by those skilled in the art, and such modifications and variations are considered to fall within the scope of this disclosure.

[0102] Exemplary aspect.

[0103] The following exemplary aspects are provided, and the numbering of these exemplary aspects should not be interpreted as indicating a level of importance:

[0104] Aspect 1 provides a porous substrate comprising:

[0105] A continuous graphite phase and a glass and / or ceramic phase, wherein the graphite phase and the glass and / or ceramic phase together form a continuous interconnected porous structure, wherein the total pore volume of the porous substrate is at least 40%, as determined by mercury porosimetry.

[0106] The porous substrate is conductive.

[0107] Aspect 2 provides a porous substrate according to aspect 1, wherein the glass and / or ceramic phase is a continuous phase.

[0108] Aspect 3 provides a porous substrate according to any one of aspects 1 to 2, wherein the continuous graphite phase is uniformly distributed in the glass and / or ceramic phase.

[0109] Aspect 4 provides a porous substrate according to any one of aspects 1 to 3, wherein the total pore volume of the porous substrate is 40% to 95%, as determined by mercury porosimetry.

[0110] Aspect 5 provides a porous substrate according to any one of aspects 1 to 4, wherein the total pore volume of the porous substrate is 50% to 95%, as determined by mercury porosimetry.

[0111] Aspect 6 provides a porous substrate according to any one of aspects 1 to 5, wherein the porous substrate has a resistance of 1 ohm to 1,000 ohms.

[0112] Aspect 7 provides a porous substrate according to any one of aspects 1 to 6, wherein the porous substrate has a resistance of 1 ohm to 100 ohms.

[0113] Aspect 8 provides a porous substrate according to any one of aspects 1 to 7, wherein the porous substrate has a compartment density of 20 compartments per square inch to 1,000 compartments per square inch.

[0114] Aspect 9 provides a porous substrate according to any one of aspects 1 to 8, wherein the porous substrate has a wall thickness of 0.002 inches to 0.05 inches.

[0115] Aspect 10 provides a porous substrate according to any one of aspects 1 to 9, wherein the porous substrate has a density of less than 1.5 g / cm³. 3 The packing density.

[0116] Aspect 11 provides a porous substrate according to any one of aspects 1 to 10, wherein the porous substrate has a density of 0.5 g / cm³. 3 Up to 1.15 g / cm 3The packing density.

[0117] Aspect 12 provides a porous substrate according to any one of aspects 1 to 11, wherein the porous substrate has a density of 0.6 g / cm³. 3 Up to 0.8 g / cm 3 The packing density.

[0118] Aspect 13 provides a porous substrate according to any one of aspects 1 to 12, wherein the porous substrate has a closed front area of ​​10% to 40%.

[0119] Aspect 14 provides a porous substrate according to any one of aspects 1 to 13, wherein the porous substrate has a closed front area of ​​20% to 30%.

[0120] Aspect 15 provides a porous substrate according to any one of aspects 1 to 14, wherein the graphite phase is uniformly distributed throughout the continuous interconnected porous structure.

[0121] Aspect 16 provides a porous substrate according to any one of aspects 1 to 15, wherein the graphite phase comprises

[0122] Graphite plates, graphite sheets, natural graphite, synthetic graphite, or combinations thereof; or

[0123] Extruded and calcined products of graphite plates, graphite sheets, natural graphite, synthetic graphite, or combinations thereof; or

[0124] Their combination.

[0125] Aspect 17 provides a porous substrate according to any one of aspects 1 to 16, wherein the graphite phase comprises graphite particles having an elongated morphology.

[0126] Aspect 18 provides a porous substrate according to aspect 17, wherein most of the graphite particles have longitudinal axes oriented in the same direction and / or axes orthogonal to their height.

[0127] Aspect 19 provides a porous substrate according to any one of aspects 17 to 18, wherein the porous substrate is an extruded product of an extrudable composition, wherein most of the graphite particles have a longitudinal axis oriented at 45° to the extrusion direction and / or an axis orthogonal to its height.

[0128] Aspect 20 provides a porous substrate according to any one of aspects 17 to 19, wherein the porous substrate is an extruded product of an extrudable composition, wherein most of the graphite particles have a longitudinal axis oriented at 30° to the extrusion direction and / or an axis orthogonal to its height.

[0129] Aspect 21 provides a porous substrate according to any one of aspects 1 to 20, wherein the porous substrate is an extruded product of an extrudable composition, and wherein the conductivity of the porous substrate along the compartment wall is higher than that through the compartment wall.

[0130] Aspect 22 provides a porous substrate according to any one of aspects 1 to 21, wherein the graphite phase accounts for 2 wt% to 30 wt% of the porous substrate.

[0131] Aspect 23 provides a porous substrate according to any one of aspects 1 to 22, wherein the graphite phase comprises 5 wt% to 20 wt% of the porous substrate.

[0132] Aspect 24 provides a porous substrate according to any one of aspects 1 to 23, wherein the glass and / or ceramic phase accounts for 10 wt% to 70 wt% of the porous substrate.

[0133] Aspect 25 provides a porous substrate according to any one of aspects 1 to 24, wherein the glass and / or ceramic phase comprises 15 wt% to 60 wt% of the porous substrate.

[0134] Aspect 26 provides a porous substrate according to any one of aspects 1 to 25, which further comprises a hollow and / or porous material comprising paper, polymer, glass, glass ceramic, ceramic, diatomaceous earth or a combination thereof.

[0135] Aspect 27 provides a porous substrate according to aspect 26, wherein the hollow and / or porous material comprises hollow glass beads.

[0136] Aspect 28 provides a porous substrate according to any one of aspects 26 to 27, wherein the hollow and / or porous material accounts for 10 wt% to 60 wt% of the porous substrate.

[0137] Aspect 29 provides a porous substrate according to any one of aspects 26 to 28, wherein the hollow and / or porous material accounts for 20 wt% to 45 wt% of the porous substrate.

[0138] Aspect 30 provides a porous substrate according to any one of aspects 1 to 29, wherein the flexural strength of the porous substrate in a 4-point bending test, normalized by the CFA, is greater than 500 psi.

[0139] Aspect 31 provides a porous substrate according to any one of aspects 1 to 30, wherein the CFA-normalized flexural strength of the porous substrate in a 4-point bending test is 500 psi to 2,500 psi.

[0140] Aspect 32 provides a porous substrate according to any one of aspects 1 to 31, wherein the CFA-normalized flexural strength of the porous substrate in a 4-point bending test is 1,000 psi to 2,500 psi.

[0141] Aspect 33 provides a porous substrate according to any one of aspects 1 to 32, wherein cristobalite accounts for 10 wt% or less of the porous substrate.

[0142] Aspect 34 provides a porous substrate according to any one of aspects 1 to 33, wherein the porous substrate has a honeycomb shape having a plurality of compartments, the compartments comprising parallel channels extending longitudinally through the honeycomb shape.

[0143] Aspect 35 provides a porous substrate according to aspect 34, wherein the honeycomb form has a perimeter profile that is circular, elliptical, square, rectangular, hexagonal, triangular, polygonal, or irregular in shape.

[0144] Aspect 36 provides a porous substrate according to any one of aspects 34 to 35, wherein when viewed from one end of the honeycomb form, the cell compartments of the honeycomb have a circular, elliptical, square, rectangular, hexagonal, triangular, polygonal, or irregular shape.

[0145] Aspect 37 provides a porous substrate according to any one of aspects 1 to 36, wherein the porous substrate comprises a coating comprising a catalyst, an adsorbent for adsorbing and desorbing CO2, or a combination thereof.

[0146] Aspect 38 provides a porous substrate according to aspect 37, wherein the adsorbent comprises zeolite, sodium carbonate, activated carbon, carbon nanotubes, metal-organic frameworks (MOFs), amines, or combinations thereof.

[0147] Aspect 39 provides a porous substrate according to any one of aspects 37 to 38, wherein the coating is directly adhered to the continuous interconnected pore structure, and wherein the porous substrate contains no intermediate layer between the coating and the glass and / or ceramic phase.

[0148] Aspect 40 provides a porous substrate according to any one of aspects 37 to 38, wherein the porous substrate comprises a carrier coating between the continuously interconnected pore structure and the coating comprising the adsorbent.

[0149] Aspect 41 provides the method according to aspect 40, wherein the carrier coating comprises γ-alumina, zeolite, activated carbon, or a combination thereof.

[0150] Aspect 42 provides a method according to any one of aspects 40 to 41, wherein the carrier coating comprises γ-alumina.

[0151] Aspect 43 provides a porous substrate comprising:

[0152] A continuous graphite phase and a glass and / or ceramic phase, wherein the graphite phase and the glass and / or ceramic phase together form a continuously interconnected porous structure, wherein the total pore volume of the porous substrate is 40% to 95%, as determined by mercury porosimetry; and

[0153] A coating on the continuously interconnected porous structure, the coating comprising a catalyst, an adsorbent for adsorbing and desorbing CO2, or a combination thereof;

[0154] The porous substrate is conductive.

[0155] Aspect 44 provides a porous substrate according to any one of aspects 1 to 43, wherein the porous substrate is an extruded and calcined product of an extrudable composition, the extrudable composition comprising:

[0156] Adhesives and / or sintering aids; and

[0157] Graphite particles.

[0158] Aspect 45 provides a porous substrate according to aspect 44, wherein the binder and / or sintering aid constitute 10 wt% to 70 wt% of the extrudable composition by dry weight.

[0159] Aspect 46 provides a porous substrate according to any one of aspects 44 to 45, wherein the binder and / or sintering aid constitute 15 wt% to 60 wt% of the extrudable composition by dry weight.

[0160] Aspect 47 provides a porous substrate according to any one of aspects 44 to 46, wherein the binder and / or sintering aid comprises an inorganic binder, a polymer, a thermosetting resin, a carbon precursor, a borate, a phosphate, a transition metal oxide, an oxide, a hydroxide, a carbonate, a silicate, an aluminosilicate, or a combination thereof.

[0161] Aspect 48 provides a porous substrate according to any one of aspects 44 to 47, wherein the graphite particles account for 2 wt% to 30 wt% of the extrudable composition based on the dry weight of the extrudable composition.

[0162] Aspect 49 provides a porous substrate according to any one of aspects 44 to 48, wherein the graphite particles account for 5 wt% to 20 wt% of the extrudable composition based on the dry weight of the extrudable composition.

[0163] Aspect 50 provides a porous substrate according to any one of aspects 44 to 49, wherein the graphite particles are graphite plates, graphite sheets, or a combination thereof.

[0164] Aspect 51 provides a porous substrate according to any one of aspects 44 to 50, wherein the graphite particles have a median longest dimension of 1 micrometer to 100 micrometers.

[0165] Aspect 52 provides a porous substrate according to any one of aspects 44 to 51, wherein the graphite particles have a median longest dimension of 5 micrometers to 15 micrometers.

[0166] Aspect 53 provides a porous substrate according to any one of aspects 44 to 52, wherein the extrudable composition further comprises one or more solvents.

[0167] Aspect 54 provides a porous substrate according to any one of aspects 44 to 53, wherein the extrudable composition further comprises a hollow and / or porous material comprising paper, polymer, glass, glass ceramic, ceramic, diatomaceous earth, or a combination thereof.

[0168] Aspect 55 provides a porous substrate according to aspect 54, wherein the hollow and / or porous material comprises hollow glass beads.

[0169] Aspect 56 provides a porous substrate according to any one of aspects 54 to 55, wherein the hollow and / or porous material accounts for 10 wt% to 60 wt% of the extrudable composition based on the dry weight of the extrudable composition.

[0170] Aspect 57 provides a porous substrate according to any one of aspects 54 to 56, wherein the hollow and / or porous material accounts for 20 wt% to 50 wt% of the extrudable composition based on the dry weight of the extrudable composition.

[0171] Aspect 58 provides a porous substrate according to any one of aspects 44 to 57, wherein the extrudable composition further comprises a pore-forming material.

[0172] Aspect 59 provides a porous substrate according to aspect 58, wherein the pore-forming material comprises starch, nut shell powder, carbon, natural polymers, synthetic polymers, carbonaceous materials, crystalline carbon, amorphous carbon, or combinations thereof.

[0173] Aspect 60 provides a porous substrate according to any one of aspects 58 to 59, wherein the pore-forming material accounts for 5 wt% to 50 wt% of the extrudable composition based on the dry weight of the extrudable composition.

[0174] Aspect 61 provides a porous substrate according to any one of aspects 58 to 60, wherein the pore-forming material accounts for 10 wt% to 30 wt% of the extrudable composition based on the dry weight of the extrudable composition.

[0175] Aspect 62 provides a porous substrate comprising:

[0176] The extruded and calcined products of the extrudable composition, the extrudable composition comprising

[0177] Adhesives and / or sintering aids, and

[0178] Graphite particles, comprising graphite plates, graphite sheets, or combinations thereof;

[0179] The porous substrate comprises a continuous graphite phase and a glass and / or ceramic phase, wherein the graphite phase and the glass and / or ceramic phase together form a continuous interconnected pore structure, and the total pore volume of the porous substrate is at least 40%, as determined by mercury porosimetry.

[0180] The porous substrate is conductive.

[0181] Aspect 63 provides a method for forming a porous substrate according to any one of aspects 44 to 62, the method comprising:

[0182] Extrusion of the extrudable composition;

[0183] The dried extruded composition; and

[0184] The dried extruded composition is fired to form the porous substrate.

[0185] Aspect 64 provides a method according to aspect 63, wherein the drying comprises heating and / or exposure to microwaves.

[0186] Aspect 65 provides a method according to any one of aspects 63 to 64, wherein the drying comprises placing the extruded composition under a vacuum.

[0187] Aspect 66 provides a method according to any one of aspects 63 to 65, wherein the drying comprises drying at a sufficient temperature and for a sufficient duration to substantially remove all solvents from the extruded composition.

[0188] Aspect 67 provides a method according to any one of aspects 63 to 66, wherein the firing comprises firing at a firing homogenization temperature of 600°C to 1100°C.

[0189] Aspect 68 provides a method according to any one of aspects 63 to 67, wherein the firing comprises firing at a firing homogenization temperature of 650°C to 950°C.

[0190] Aspect 69 provides a method according to any one of aspects 63 to 68, wherein the firing includes firing for 1 hour to 24 hours.

[0191] Aspect 70 provides the method according to any one of aspects 63 to 69, wherein the firing includes firing for a duration of 2 hours to 6 hours.

[0192] Aspect 71 provides a method according to any one of aspects 63 to 70, wherein the method comprises increasing the temperature of the dried extruded composition at a rate of 10°C / hour to 100°C / hour to a homogenizing firing temperature.

[0193] Aspect 72 provides a method according to any one of aspects 63 to 71, wherein the method comprises increasing the temperature of the dried extruded composition at a rate of 30°C / hour to 70°C / hour to a firing homogenization temperature.

[0194] Aspect 73 provides a method according to any one of aspects 63 to 72, wherein the firing comprises firing in an atmosphere containing an oxygen concentration low enough to prevent the graphene particles from oxidizing during firing.

[0195] Aspect 74 provides the method according to any one of aspects 63 to 73, wherein the firing is carried out under an inserted gas.

[0196] Aspect 75 provides the method according to any one of aspects 63 to 74, wherein the porous substrate has a shrinkage rate of 0% to 15% compared to the extruded composition.

[0197] Aspect 76 provides the method according to any one of aspects 63 to 75, wherein the porous substrate has a shrinkage rate of 2% to 7% compared to the extruded composition.

[0198] Aspect 77 provides a method according to any one of aspects 63 to 76, wherein the firing comprises firing the dried extruded composition in a furnace containing

[0199] Unheated insertion portion

[0200] The heated central part is maintained at a temperature of approximately 920°C to 1000°C, and

[0201] Unheated outlet section.

[0202] Aspect 78 provides the method according to aspect 77, wherein the heated central portion is maintained at a temperature of about 930°C to about 970°C.

[0203] Aspect 79 provides a method according to any one of aspects 77 to 78, wherein the method comprises maintaining the dried extruded composition at a preheating distance from the unheated insertion portion for a preheating duration prior to inserting the dried extruded composition into the furnace, wherein the preheating distance is 0.01 m to 0.1 m and the preheating duration is 1 minute to 10 minutes.

[0204] Aspect 80 provides a method according to any one of aspects 77 to 79, wherein the distance from the inlet of the unheated insert portion to the outlet of the unheated outlet portion is the total length (L) of the furnace, wherein the method comprises moving the dried extruded composition through the furnace at a rate of about 0.01*L per minute to 0.1*L per minute, and further comprises holding the dried extruded composition stationary in the heated central portion for a heating duration of 5 minutes to 1 hour.

[0205] Aspect 81 provides the method according to aspect 80, wherein the rate is 0.03*L to 0.07*L.

[0206] Aspect 82 provides the method according to any one of aspects 80 to 81, wherein the heating duration is 10 minutes to 30 minutes.

[0207] Aspect 83 provides the method according to any one of aspects 77 to 82, wherein the firing is completed over a period of 20 minutes to 2 hours.

[0208] Aspect 84 provides the method according to any one of aspects 77 to 83, wherein the firing is completed over a period of 30 minutes to 1 hour.

[0209] Aspect 85 provides a method according to any one of aspects 77 to 84, wherein the extrudable composition comprises hollow glass beads.

[0210] Aspect 86 provides a method for forming a porous substrate, the method comprising:

[0211] Extrudable compositions comprising

[0212] Adhesives and / or sintering aids, and

[0213] Graphite particles, comprising graphite plates, graphite sheets, or combinations thereof;

[0214] The dried extruded composition; and

[0215] The dried extruded composition is calcined to form the porous substrate, wherein the porous substrate comprises a continuous graphite phase and a glass and / or ceramic phase, wherein the graphite phase and the glass and / or ceramic phase together form a continuous interconnected pore structure, wherein the total pore volume of the porous substrate is at least 40%, as determined by mercury porosimetry.

[0216] The porous substrate is conductive.

[0217] Aspect 86 provides a method for forming a porous substrate, the method comprising:

[0218] Extrudable compositions comprising

[0219] Adhesives and / or sintering aids,

[0220] Graphite particles, comprising graphite plates, graphite sheets, or combinations thereof, and

[0221] Hollow glass beads;

[0222] The dried extruded composition; and

[0223] The dried extruded composition is calcined to form the porous substrate, wherein the calcination comprises calcining the dried extruded composition in a furnace containing...

[0224] Unheated insertion portion

[0225] The heated central part is maintained at a temperature of approximately 920°C to 1000°C, and

[0226] Unheated outlet section

[0227] The distance from the inlet of the unheated insert portion to the outlet of the unheated outlet portion is the total length (L) of the furnace, wherein the method comprises moving the dried extruded composition through the furnace at a rate of about 0.01*L per minute to 0.1*L per minute, and further comprises holding the dried extruded composition stationary in the heated central portion for a heating duration of 5 minutes to 1 hour, wherein the firing is completed within a duration of 20 minutes to 2 hours;

[0228] The porous substrate comprises a continuous graphite phase and a glass and / or ceramic phase, wherein the graphite phase and the glass and / or ceramic phase together form a continuous interconnected pore structure, and the total pore volume of the porous substrate is at least 40%, as determined by mercury porosimetry.

[0229] The porous substrate is conductive.

[0230] Aspect 87 provides a method for forming a porous substrate, the method comprising:

[0231] Extrudable compositions comprising

[0232] Adhesives and / or sintering aids;

[0233] The dried extruded composition; and

[0234] The dried extruded composition is calcined to form the porous substrate;

[0235] The firing process involves firing the dried extruded composition in a furnace, the furnace comprising...

[0236] Unheated insertion portion

[0237] The heated central part is maintained at a temperature of approximately 920°C to 1000°C, and

[0238] Unheated outlet section.

[0239] Aspect 88 provides the method according to aspect 87, wherein the heated central portion is maintained at a temperature of about 930°C to about 970°C.

[0240] Aspect 89 provides a method according to any one of aspects 87 to 88, wherein the method comprises maintaining the dried extruded composition at a preheating distance from the unheated insertion portion for a preheating duration prior to inserting the dried extruded composition into the furnace, wherein the preheating distance is 0.01 m to 0.1 m and the preheating duration is 1 minute to 10 minutes.

[0241] Aspect 90 provides a method according to any one of aspects 87 to 89, wherein the distance from the inlet of the unheated insert portion to the outlet of the unheated outlet portion is the total length (L) of the furnace, wherein the method comprises moving the dried extruded composition through the furnace at a rate of about 0.01*L per minute to 0.1*L per minute, and further comprises holding the dried extruded composition stationary in the heated central portion for a heating duration of 5 minutes to 1 hour.

[0242] Aspect 91 provides the method according to aspect 90, wherein the rate is from 0.03*L to 0.07*L.

[0243] Aspect 92 provides a method according to any one of aspects 90 to 91, wherein the heating duration is 10 minutes to 30 minutes.

[0244] Aspect 93 provides a method according to any one of aspects 87 to 92, wherein the firing is completed over a period of 20 minutes to 2 hours.

[0245] Aspect 94 provides the method according to any one of aspects 87 to 93, wherein the firing is completed over a period of 30 minutes to 1 hour.

[0246] Aspect 95 provides a method according to any one of aspects 87 to 94, wherein the extrudable composition comprises hollow glass beads.

[0247] Aspect 96 provides a method for forming a porous substrate, the method comprising:

[0248] Extrudable compositions, the extrudable compositions comprising

[0249] Adhesives and / or sintering aids, and

[0250] Hollow glass beads;

[0251] The dried extruded composition; and

[0252] The dried extruded composition is calcined to form the porous substrate;

[0253] The firing process includes firing the dried extruded composition in a furnace, the furnace comprising...

[0254] Unheated insertion portion

[0255] The heated central part is maintained at a temperature of approximately 920°C to 1000°C, and

[0256] Unheated outlet section;

[0257] The distance from the inlet of the unheated insert portion to the outlet of the unheated outlet portion is the total length (L) of the furnace, wherein the method includes moving the dried extruded composition through the furnace at a rate of about 0.01*L per minute to 0.1*L per minute, and further includes holding the dried extruded composition stationary in the heated central portion for a heating duration of 5 minutes to 1 hour, wherein the firing is completed within a duration of 20 minutes to 2 hours.

[0258] Aspect 97 provides a method for using a porous substrate according to any one of aspects 37 to 42, the method comprising:

[0259] The porous substrate is exposed to an airflow containing CO2 to at least partially adsorb the CO2 from the airflow into the coating on the porous substrate; and

[0260] CO2 is desorbed from the coating on the porous substrate, the desorption comprising applying a potential to both ends of the porous substrate to heat the porous substrate.

[0261] Aspect 98 provides a porous substrate or method according to any one or any combination of aspects 1 to 97, which is optionally configured such that all the elements or options described are available or selectable.

Claims

1. A porous substrate comprising: Continuous graphite phase, and Glass and / or ceramic phases, The graphite phase and the glass and / or ceramic phase together form a continuous interconnected porous structure, wherein the total pore volume of the porous substrate is at least 40%, as determined by mercury porosimetry. The porous substrate is electrically conductive due to the continuous graphite phase.

2. The porous substrate according to claim 1, wherein the continuous graphite phase is uniformly distributed in the glass and / or ceramic phase.

3. The porous substrate according to any one of claims 1 to 2, wherein the porous substrate has a resistance of 1 ohm to 1,000 ohms.

4. The porous substrate according to any one of claims 1 to 3, wherein the porous substrate has a density of 0.5 g / cm³. 3 Up to 1.5 g / cm 3 The packing density of the porous substrate, determined by mercury porosimetry, is 40% to 95% of the total pore volume, and the porous substrate has 10% to 40% of a closed front surface area.

5. The porous substrate according to any one of claims 1 to 4, wherein the graphite phase comprises Graphite plates, graphite sheets, natural graphite, synthetic graphite, or combinations thereof; or Extruded and calcined products of graphite plates, graphite sheets, natural graphite, synthetic graphite, or combinations thereof; or Their combination.

6. The porous substrate according to any one of claims 1 to 5, wherein the graphite phase comprises graphite particles having an elongated morphology, wherein the porous substrate is an extruded product of an extrudable composition, wherein most of the graphite particles have a longitudinal axis oriented at 45° to the extrusion direction and / or an axis orthogonal to its height.

7. The porous substrate of claim 6, wherein the conductivity of the porous substrate along the compartment wall is higher than the conductivity through the compartment wall.

8. The porous substrate according to any one of claims 1 to 7, wherein the graphite phase accounts for 2 wt% to 30 wt% of the porous substrate, and wherein the glass and / or ceramic phase accounts for 10 wt% to 70 wt% of the porous substrate.

9. The porous substrate according to any one of claims 1 to 8, wherein the CFA-normalized flexural strength of the porous substrate in a 4-point bending test is 500 psi to 2,500 psi.

10. The porous substrate according to any one of claims 1 to 9, wherein the porous substrate has a honeycomb shape having a plurality of compartments, each compartment comprising parallel channels extending longitudinally through the honeycomb shape, wherein the porous substrate has a compartment density of 20 to 1,000 compartments per square inch and a wall thickness of 0.002 to 0.05 inches.

11. The porous substrate according to any one of claims 1 to 10, wherein the porous substrate comprises a coating comprising an adsorbent, a catalyst, or a combination thereof for adsorbing and desorbing CO2.

12. The porous substrate according to any one of claims 1 to 11, wherein the porous substrate is conductive in both the axial direction of the substrate and in the transverse direction perpendicular to the axial direction.

13. A porous substrate comprising: A continuous graphite phase and a glass and / or ceramic phase, wherein the graphite phase and the glass and / or ceramic phase together form a continuously interconnected porous structure, wherein the total pore volume of the porous substrate is 40% to 95%, as determined by mercury porosimetry; and A coating on the continuously interconnected porous structure, the coating comprising a catalyst, an adsorbent for adsorbing and desorbing CO2, or a combination thereof; The porous substrate is conductive.

14. A method of using a porous substrate according to any one of claims 12 to 13, the method comprising: The porous substrate is exposed to a gas stream comprising CO2, so that the CO2 from the gas stream is at least partially adsorbed into the coating containing the adsorbent on the porous substrate; and CO2 is desorbed from the coating on the porous substrate, the desorption comprising applying a potential to both ends of the porous substrate to heat the porous substrate.

15. The porous substrate according to any one of claims 1 to 14, wherein the porous substrate is an extruded and fired product of an extrudable composition, the extrudable composition comprising: Adhesives and / or sintering aids; and Graphite particles.

16. The porous substrate of claim 15, wherein the binder and / or sintering aid constitute 10 wt% to 70 wt% of the extrudable composition by dry weight, and wherein the graphite particles constitute 2 wt% to 30 wt% of the extrudable composition.

17. The porous substrate according to any one of claims 15 to 16, wherein the binder and / or sintering aid comprises an inorganic binder, a polymer, a thermosetting resin, a carbon precursor, a borate, a phosphate, a transition metal oxide, an oxide, a hydroxide, a carbonate, a silicate, an aluminosilicate, or a combination thereof.

18. The porous substrate according to any one of claims 15 to 17, wherein the graphite particles are graphite plates, graphite sheets, or combinations thereof, wherein the graphite particles have a median longest dimension of 1 micrometer to 100 micrometers, and wherein the graphite particles have an aspect ratio of 1:5 to 1:

15.

19. A porous substrate comprising: The extruded and calcined products of the extrudable composition, the extrudable composition comprising Adhesives and / or sintering aids, and Graphite particles, comprising graphite plates, graphite sheets, or combinations thereof; The porous substrate comprises a continuous graphite phase and a glass and / or ceramic phase, wherein the graphite phase and the glass and / or ceramic phase together form a continuous interconnected pore structure, and the total pore volume of the porous substrate is at least 40%, as determined by mercury porosimetry. The porous substrate is conductive.

20. A method for forming a porous substrate according to any one of claims 15 to 19, the method comprising: Extrusion of the extrudable composition; The dried extruded composition; and The dried extruded composition is fired to form the porous substrate.

21. A method for forming a porous substrate, the method comprising: Extrudable compositions, the extrudable compositions comprising Adhesives and / or sintering aids, and Hollow glass beads; as well as The extruded composition is fired to form the porous substrate; The firing process includes firing the extruded composition in a furnace, the furnace comprising... Unheated insertion portion The heated central part is maintained at a temperature of approximately 920°C to 1000°C, and Unheated outlet section; The distance from the inlet of the unheated insert portion to the outlet of the unheated outlet portion is the total length (L) of the furnace, wherein the method includes moving the extruded composition through the furnace at a rate of about 0.01*L per minute to 0.1*L per minute, and further includes holding the extruded composition stationary in the heated central portion for a heating duration of 5 minutes to 1 hour, wherein the firing is completed within a duration of 20 minutes to 2 hours.

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