Nanoporous organic polymers for high pressure gas storage

Abstract

The present disclosure relates to methods of making porous gas storage materials for storing hydrogen and / or oxygen and / or nitrogen. The method includes providing an aromatic ring-containing monomer, the monomer including at least two aromatic rings. The method also includes subjecting the monomer to a metal-catalyzed cross-coupling reaction to form a gas storage material, the material including a cross-linked polymeric backbone and including a plurality of pores for gas adsorption, the cross-linked polymeric backbone having aromatic ring-containing monomer units directly connected by covalent bonds between the aromatic rings. Alternatively, the method includes cross-linking the monomer by a Friedel-Crafts alkylation reaction to form a gas storage material including a cross-linked polymeric backbone, but the cross-linked polymeric backbone has aromatic ring-containing monomer units connected by cross-linking moieties between the aromatic rings. The alternative material also includes a plurality of pores for gas adsorption. However, in this alternative material, at least a subset of the aromatic ring-containing monomer units includes at least five aromatic rings. Otherwise, in this alternative material, at least a subset of the aromatic ring-containing monomer units is selected from the group consisting of Formula (I). The present disclosure also encompasses porous gas storage materials made according to these methods that are aggregated using a binder to form one or more macroscopic objects.

Description

Technical Field

[0001] This invention relates to porous materials and related preparation methods, as well as methods for storing gases. More specifically, this invention relates to materials and methods for storing gases comprising or rich in hydrogen (H2); and / or oxygen (O2); and / or nitrogen (N2). More specifically, this invention relates to materials and methods for storing compressed H2, and / or compressed O2, and / or compressed N2. Background Technology

[0002] The demand for alternative fuels is greater than ever before. This demand necessitates the storage of light gases, such as H2, at increasingly higher pressures. Storage of auxiliary gases, such as O2 and / or N2, is also required.

[0003] Gas storage in highly porous materials has been proposed and studied, but existing materials for this purpose still have inherent limitations. These materials include widely described zeolites, metal-organic frameworks (MOFs), porous coordination polymers (PCPs), and general organometallic compounds. In existing organometallic compounds, the positively charged metal atoms bound to the organic ligands are extremely sensitive to polar substances such as water, which can contaminate and degrade the working material during its lifetime. Water contamination is also a problem in compounds containing open metal sites due to the susceptibility of porous materials to deactivation. Furthermore, most metal-containing materials achieve maximum effective adsorption at relatively low pressures. Moreover, adsorption measurements in studies are typically limited to below 40 bar. Pressure ranges below 40 bar, or even below 100 bar, may be insufficient, at least for some storage projects.

[0004] WO 2016 / 087471 A1 discloses a method for storing gases using a porous gas storage material comprising a cross-linked polymer backbone and a plurality of pores for gas adsorption. The cross-linked polymer backbone comprises aromatic ring-containing monomer units, each monomer unit comprising at least two aromatic rings. The aromatic ring-containing monomer units are linked by covalent cross-linking bonds between the aromatic rings to form a stable, rigid nanoporous material for storing gases at pressures significantly above atmospheric pressure, such as exceeding 100 bar. However, given the similarities among various organic molecules, this material has been specifically designed and tested for storing and transporting compressed natural gas (CNG) and potentially CO2. WO 2016 / 087471 A1 does not address the ability of similar materials to successfully store typically lighter gases such as H2, or different inorganic gases such as O2 and / or N2. While the storage of N2 and O2 has been considered, H2 is of particular interest due to its small size and inherent storage challenges.

[0005] Compared to existing technologies, it is generally desired that: (a) a relatively larger amount of gas can be stored per unit available storage volume at a given pressure; and / or (b) the same amount of gas can be stored per unit available storage volume at a relatively lower pressure, thereby allowing for a reduction in the amount of material used in the associated containers for gas storage, for example, by reducing the wall thickness of the containers; and / or (c) the same amount of gas can be stored using fewer storage volumes at a given pressure, thereby reducing the overall size of the associated containers or storage systems. As will be readily understood, these objectives are valid for any gas to be stored, including H2, O2, and / or N2. Nevertheless, H2 has received more attention both academically and practically given its applications in many potential industrial applications, including energy systems. Therefore, there is a need for porous materials for high-pressure gas storage that offer improved gas adsorption performance, at least at relatively higher pressures, compared to porous materials for high-pressure gas storage described in the prior art. This application aims to address one or more of the problems associated with the prior art, particularly for H2, but also for O2 and / or N2. Summary of the Invention

[0006] This invention provides materials and methods for storing H2, particularly under high pressure, but also O2 and / or N2, overcoming at least some of the limitations associated with materials proposed to date for the aforementioned purposes. This is useful for a wide range of applications. The invention is based on high surface area porous materials. This is achieved by using porous gas storage materials comprising a cross-linked polymer backbone.

[0007] According to an aspect of this disclosure, a method for storing a gas comprising hydrogen and / or oxygen and / or nitrogen is provided, the method comprising: A container is provided for receiving the gas, the container being designed to withstand a nominal internal pressure P1 greater than atmospheric pressure; A porous gas storage material is provided within the container, the gas storage material comprising: A cross-linked polymer backbone forming multiple pores for gas adsorption, wherein the cross-linked polymer backbone comprises aromatic ring-containing monomer units, each monomer unit comprising at least two aromatic rings, wherein the aromatic ring-containing monomer units are connected by covalent cross-linking bonds between the aromatic rings; and The gas is loaded into the container to the pressure P1.

[0008] P1 can reach up to 700 bar.

[0009] The container may include or may be in the form of a pressure vessel, the pressure vessel including a load-bearing structural part containing composite materials.

[0010] The pressure vessel may include a metal or polymer liner for containing gas.

[0011] The crosslinked polymer backbone may include monomer units containing aromatic rings, wherein the monomer units include at least three aromatic rings, optionally at least four aromatic rings, optionally at least five aromatic rings, or optionally at least six aromatic rings.

[0012] The crosslinked polymer backbone may include copolymers, which include two or more monomer units containing aromatic rings with different structures.

[0013] At least one subset of the aromatic ring-containing monomer units may include at least four aromatic rings.

[0014] At least one subset of the aromatic ring-containing monomer unit or the monomer unit of the copolymer may include two or more aromatic rings fused or connected in a conjugated system.

[0015] The aromatic ring-containing monomer unit can be: a) Directly connected via covalent bonds between aromatic rings; or b) Linked by cross-linking portions between aromatic rings, wherein optionally the cross-linking portions are aliphatic groups.

[0016] At least a subset of the aromatic ring-containing monomer units may include two aromatic rings as described below: a) The center-to-center spatial distance between the two aromatic rings is at least 0.2 nm, optionally at least 0.3 nm, optionally at least 0.4 nm, optionally at least 0.5 nm, optionally at least 0.6 nm, optionally at least 0.7 nm, and optionally at least 0.8 nm; and / or b) The two aromatic rings are separated from each other by four or more bonds.

[0017] At least one subset of the aromatic ring-containing monomer units can be selected from the group consisting of: .

[0018] According to another aspect of this disclosure, a method for preparing a porous gas storage material for storing hydrogen and / or oxygen and / or nitrogen is provided, wherein the method comprises: Provides a monomer containing aromatic rings, said monomer comprising at least two aromatic rings; and The monomers are subjected to a metal-catalyzed cross-coupling reaction to form a gas storage material comprising a cross-linked polymer backbone having aromatic ring-containing monomer units and including a plurality of pores for gas adsorption, wherein the aromatic ring-containing monomer units are directly connected by covalent bonds between aromatic rings.

[0019] The cross-linked polymer backbone can be defined as above.

[0020] The method may include a nickel-catalyzed cross-coupling reaction, optionally a Yamamoto cross-coupling reaction.

[0021] According to another aspect of this disclosure, a method for preparing a porous gas storage material for storing hydrogen and / or oxygen and / or nitrogen is provided, wherein the method comprises: Provides a monomer containing aromatic rings, said monomer comprising at least two aromatic rings; and, The monomer is crosslinked via a Fried-Krawc alkylation reaction to form a gas storage material comprising a crosslinked polymer backbone and including a plurality of pores for gas adsorption. The crosslinked polymer backbone has aromatic ring-containing monomer units linked by crosslinking portions (optionally aliphatic groups, e.g., alkyl groups) between aromatic rings, wherein at least a subset of the aromatic ring-containing monomer units comprises at least five aromatic rings; or wherein at least a subset of the aromatic ring-containing monomer units is selected from the group consisting of: .

[0022] The method may include using dimethylformaldehyde and ferric chloride (III) or acidic conditions as catalysts to crosslink the monomers via a Fried-Krawc alkylation reaction.

[0023] According to another aspect of this disclosure, a porous gas storage material for storing hydrogen and / or oxygen and / or nitrogen is provided, comprising: Crosslinked polymer backbone; and Multiple pores for gas adsorption, wherein the cross-linked polymer backbone comprises aromatic ring-containing monomer units, wherein the aromatic ring-containing monomer units comprise at least two aromatic rings, and wherein the aromatic ring-containing monomer units are directly connected by covalent bonds between the aromatic rings.

[0024] According to another aspect of this disclosure, a porous gas storage material for storing hydrogen and / or oxygen and / or nitrogen is provided, comprising: Crosslinked polymer backbone; and Multiple pores for gas adsorption, wherein the crosslinked polymer backbone comprises aromatic ring-containing monomer units, each aromatic ring-containing monomer unit comprising at least two aromatic rings, and wherein the aromatic ring-containing monomer units are linked by crosslinking portions (optionally aliphatic groups, e.g., alkyl groups) between the aromatic rings, and wherein at least one subset of the aromatic ring-containing monomer units comprises at least five aromatic rings; or wherein at least one subset of the aromatic ring-containing monomer units is selected from the group consisting of: .

[0025] The porous gas storage material described in this article can be an amorphous material.

[0026] The BET specific surface area of ​​the gas storage material described in this article can be greater than approximately 750 m². 2 g -1 Optional site greater than approximately 850m 2 g -1 Optional location greater than approximately 1000m 2 g -1 Optional site larger than approximately 1250m 2 g -1 Optional site larger than approximately 1500m 2 g -1 Optional location greater than approximately 2000m 2 g -1 Optional site greater than approximately 3000m 2 g -1 and optionally greater than about 4000m 2 g -1 .

[0027] The pores mentioned in this article may include micropores.

[0028] The pore volume of the gas storage material described in this article can be greater than approximately 0.40 cm³. 3 g -1 Optional, larger than approximately 0.50cm 3 g -1 Optional, larger than approximately 0.60cm 3 g -1 Optional, larger than approximately 0.90cm 3 g -1 Optional, larger than approximately 1.00cm 3 g -1 Optional, larger than approximately 0.60cm 3 g -1 Optional, larger than approximately 1.20cm 3 g -1 Optional, larger than approximately 1.40cm 3 g -1 Optional, larger than approximately 1.50cm 3 g -1 Optional, larger than approximately 2.00cm 3 g -1 Optional, larger than approximately 2.70cm 3 g -1 and optionally larger than about 3.00cm 3 g -1 .

[0029] According to another aspect of this disclosure, a porous gas storage material described herein is provided for storing hydrogen and / or oxygen and / or nitrogen at pressures above atmospheric pressure.

[0030] According to another aspect of this disclosure, use is provided for storing hydrogen and / or oxygen and / or nitrogen at pressures above atmospheric pressure using the porous gas storage material described herein. Attached Figure Description

[0031] The following describes specific embodiments of the invention by way of example only and with reference to the accompanying drawings, wherein: Figure 1 A) Nitrogen adsorption isotherm collected by BIC-1 at 77 K (mmol / g). BET surface area: 2062 m² 2 / g; Langmuir surface area: 2615m² 2 / g; Pore volume: 2.00cm³ 3 / g;B) Nitrogen adsorption isotherm (cm) collected by BIC-1 at 77K 3 / g, STP); C) Thermogravimetric analysis of BIC-1, measured at 25°C to 1000°C under an oxidizing atmosphere (dry air, 50 mL / min).

[0032] Figure 2 A) Nitrogen adsorption isotherm collected by BIC-2 at 77 K (mmol / g). BET surface area: 3721 m² 2 / g; Langmuir surface area: 4244m² 2 / g; Pore volume: 2.26cm³ 3 / g;B) Nitrogen adsorption isotherm (cm) collected from BIC-2 at 77K 3 / g, STP); C) Thermogravimetric analysis of BIC-2, measured at 25℃ to 1000℃ under an oxidizing atmosphere (dry air, 50 mL / min).

[0033] Figure 3 A) Nitrogen adsorption isotherm collected by BIC-3 at 77 K (mmol / g). BET surface area: 1548 m² 2 / g; Langmuir surface area: 1866m² 2 / g; Pore volume: 1.01cm³ 3 / g;B) Nitrogen adsorption isotherm (cm) collected from BIC-3 at 77K 3 / g, STP); C) Thermogravimetric analysis of BIC-3, measured at 25°C to 1000°C under an oxidizing atmosphere (dry air, 50 mL / min).

[0034] Figure 4 A) H2 adsorption isotherm collected by BIC-1 at 77K; B) H2 adsorption isotherm collected by BIC-1 at 195K.

[0035] Figure 5 Reproducibility of H2 adsorption isotherms of BIC-1 at 77 K (A) and 195 K (B).

[0036] Figure 6 A) H2 adsorption isotherm collected by BIC-2 at 77K; B) H2 adsorption isotherm collected by BIC-2 at 195K.

[0037] Figure 7 Reproducibility of H2 adsorption isotherms of BIC-2 at 77 K (A) and 195 K (B).

[0038] Figure 8 A) H2 adsorption isotherm collected by BIC-3 at 77K; B) H2 adsorption isotherm collected by BIC-3 at 195K.

[0039] Figure 9 Reproducibility of H2 adsorption isotherms of BIC-3 at 77 K (A) and 195 K (B).

[0040] Figure 10 BIC-1 (see BIC-1) Figure 10 A) 13 C { 1 H} CP MAS spectra were acquired at 293 K, 7.04 T, and 12.5 kHz, with contact times of a) 2 ms and b) 0.05 ms. Figure 10 B).

[0041] Figure 11 BIC-2 ( Figure 11 A) 13 C{ 1 HCP MAS spectra were acquired at 293 K, 7.04 T, and 12.5 kHz, with contact times of a) 2 ms and b) 0.05 ms. Figure 11 B).

[0042] Figure 12 BIC-3 ( Figure 12 A) 13 C{ 1 HCPMAS spectra were acquired at 293 K, 7.04 T, and 12.5 kHz, with contact times of a) 2 ms and b) 0.05 ms. Figure 12 B).

[0043] Figure 13A) Experimental H2 adsorption isotherms of BIC-1 at 77 K and pressures up to 250 bar (wt%); B) H2 adsorption isotherms of BIC-1 at pressures up to 700 bar (wt%). Experimental data were up to 100 bar and extrapolated to 250 bar and 700 bar using the two-site Langmuir equation.

[0044] Figure 14 A) Experimental H2 adsorption isotherms of BIC-1 at 195 K and pressures up to 250 bar (wt%); B) H2 adsorption isotherms of BIC-1 at pressures up to 700 bar (wt%). Experimental data were up to 100 bar and extrapolated to 250 bar and 700 bar using the Langmuir-Freundlich equation.

[0045] Figure 15 A) Experimental H2 adsorption isotherms of BIC-2 at 77 K and pressures up to 250 bar (wt%); B) H2 adsorption isotherms of BIC-2 at pressures up to 700 bar (wt%). Experimental data were up to 100 bar and extrapolated to 250 bar and 700 bar using the Langmuir-Freundlich equation.

[0046] Figure 16 A) Experimental H2 adsorption isotherms of BIC-2 at 195 K and pressures up to 250 bar (wt%); B) H2 adsorption isotherms of BIC-2 at pressures up to 700 bar (wt%). Experimental data were up to 100 bar and extrapolated to 250 bar and 700 bar using the Langmuir-Freundlich equation. Detailed Implementation

[0047] The gas storage material disclosed herein comprises a cross-linked polymer framework. This cross-linked polymer framework is preferably a highly cross-linked polymer framework. The highly cross-linked polymers are self-aligned to form a highly porous amorphous cross-linked polymer framework. Compared to simple cross-linked polymers, highly cross-linked polymers have smaller pore sizes and relatively higher surface areas and porosity. The highly cross-linked polymers are prepared by extensively cross-linking aromatic ring-containing monomers, each monomer providing a monomer unit within the polymer framework. The monomers are linked by covalent cross-linking bonds between aromatic rings, preferably carbon-carbon bonds. This can be achieved through direct C / C bonds between the aromatic rings of the individual monomer units, optionally via metal-catalyzed cross-coupling reactions, optionally via Yamamoto-type cross-coupling reactions, or via covalent linkages formed by the cross-linked portions between the aromatic rings of the individual monomer units, optionally via Fried-Krawtz alkylation reactions. Following either of these linkage strategies, extensive cross-linking of the monomers results in the formation of a three-dimensional porous rigid framework with a very high surface area. The higher the degree of cross-linking of the monomers in the network, the larger the specific surface area available for gas adsorption. In hypercrosslinked polymers, crosslinking and polymerization occur simultaneously during synthesis via the same reaction. Therefore, unlike simple crosslinked polymers, there may be no distinction between bonds between monomer units within the polymer chain and crosslinking bonds in hypercrosslinked polymers. Aromatic ring-containing monomers can have multiple reaction sites, thus forming multiple crosslinking bonds with other monomers to create a lattice structure. This results in a highly crosslinked backbone, where any monomer unit can bond to two or more other monomer units.

[0048] The formation of covalent crosslinks immobilizes and rigidifies the aromatic ring-containing monomer units, causing them to arrange themselves in a loosely packed manner. The aromatic ring-containing monomers themselves can possess high structural rigidity. The selection of aromatic ring-containing monomers is based on their inherent tendency to arrange themselves in a loosely packed manner, independent of the type of crosslinks formed between subsequent monomer units. Multiple aromatic rings in the monomer (especially six-membered rings, such as benzene and its derivatives, or benzene-containing systems) provide this structural stability to the porous framework. These monomers are stable and possess high electron densities, high enough to facilitate interactions with methane and hydrogen molecules, as well as the positively charged carbon atoms of carbon dioxide. The multiple reaction sites on the aromatic ring-containing monomers also provide a tendency for network branching and spatial evolution.

[0049] Aromatic ring-containing monomers are polymerized / crosslinked to form a crosslinked polymer backbone comprising aromatic ring-containing monomer units, wherein each monomer provides a monomer unit within the polymer backbone. Regardless of the synthetic route, the core molecular structure of the aromatic ring-containing monomer is retained within the individual aromatic ring-containing monomer units within the crosslinked polymer backbone. Those skilled in the art will understand that, depending on the method used to crosslink / polymerize the monomer, the monomer may include leaving groups that are no longer present in the monomer units of the polymer backbone.

[0050] The polymer is typically formed from at least 10 monomer units, optionally at least 20 monomer units, and optionally at least 100 monomer units. The crosslinked polymer backbone may include aromatic ring-containing monomer units, wherein all aromatic ring-containing monomer units have the same structure. Alternatively, the crosslinked polymer backbone may include a copolymer comprising two or more subsets of structurally different monomer units. Thus, the copolymer will be formed from at least two subsets of aromatic ring-containing monomer units, each with a different structure, or from at least one subset of aromatic ring-containing monomer units and one or more structurally different monomer units. For example, the copolymer may include two structurally different monomer units, or three structurally different monomer units (in which case, the copolymer may also be referred to as a ternary copolymer).

[0051] As used herein, the term "aromatic ring" includes carbocyclic aromatic rings and heterocyclic aromatic rings. An aromatic ring can be a C6 carbocyclic aromatic ring, a 5-membered heterocyclic aromatic ring, or a 6-membered heterocyclic aromatic ring. In addition to the carbon ring atom, a heterocyclic aromatic ring includes one or more cyclic heteroatoms selected from oxygen, nitrogen, phosphorus, and sulfur, preferably nitrogen. Optionally, the aromatic ring is phenyl, pyrrolyl, imidazolyl, pyrazolyl, isoxazolyl, oxazolyl, thiazolyl, pyridinyl, pyrimidinyl, or pyrazinyl, preferably phenyl or pyrrolyl. An aromatic ring can optionally be fused with another aromatic ring or another cyclic organic moiety to form a bicyclic, tricyclic, or polycyclic system. Preferably, the bicyclic, tricyclic, or polycyclic system is a conjugated system. Thus, in this document, a bicyclic conjugated ring system, such as naphthyl, comprises two aromatic rings. Bicyclic, tricyclic, or polycyclic systems are preferably composed of naphthyl, anthraceneyl, tetraphenyl, carbazolyl, indoleyl, isoindoleyl, indazoleyl, indeneyl, isoquinolinyl, quinazolinyl, or quinolinyl, with anthraceneyl, tetraphenyl, or carbazolyl being preferred. The aromatic ring may optionally be substituted with one or more groups selected from the group consisting of aliphatic (preferably alkyl), halogen (preferably fluorine), -COOR, -NR2, or -OR, wherein R is independently hydrogen or an aliphatic group (e.g., alkyl).

[0052] The crosslinking moiety is a group capable of bonding with at least two other groups. According to the first crosslinking strategy, the crosslinking moiety is a group that can be introduced into the crosslinked polymer backbone to connect aromatic ring-containing monomer units. The crosslinking moiety can be introduced via a Fried-Krawc alkylation reaction, wherein the crosslinking moiety is an alkyl source (i.e., an electrophilic group) used for the alkylation reaction. The crosslinking moiety can be an aliphatic group, preferably an alkyl group.

[0053] According to the second crosslinking strategy, aromatic ring-containing monomer units can be crosslinked via metal-catalyzed cross-coupling reactions, or optionally via Yamamoto-type cross-coupling reactions.

[0054] As used herein, "aliphatic" can refer to a straight-chain, branched, or cyclic aliphatic group that is fully saturated or comprises one or more unsaturated units. An aliphatic group may comprise one to six carbon atoms, preferably one to three, and most preferably one carbon atom. The aliphatic group is preferably alkyl, preferably methyl. The aliphatic group may be substituted with one or more groups selected from aliphatic (preferably alkyl) or halogen (preferably fluorine) groups, or may comprise one or more unsaturated units (e.g., alkene or alkyne moieties). As used herein, the term alkyl (or alkane) refers to a straight-chain or branched alkyl group. As used herein, the term alkenyl (or alkene) refers to an alkyl chain comprising at least one C=C double bond. As used herein, the term alkynyl (or alkyne) refers to an alkyl chain comprising at least one C≡C triple bond.

[0055] The materials described herein can be defined as nanoporous materials. Nanoporous materials typically contain pores of 100 nm or smaller. Nanoporous materials can be classified into three categories: microporous materials (pore size less than 2 nm, typically 0.2 nm to 2 nm), mesoporous materials (pore size 2 nm to 50 nm), and macroporous materials (pore size greater than 50 nm). The gas storage material of the present invention preferably comprises micropores (pore size preferably concentrated between about 1 nm and about 2 nm, optionally between about 1.0 nm and about 1.8 nm, optionally between about 1.2 nm and about 1.8 nm). The pore size can be estimated by density functional theory (DFT) analysis or other alternative methods from the nitrogen adsorption branch at 77 K shown in the examples. The pore size distribution (PSD) is calculated using nonlocal density functional theory (DFT) applied to the N2 adsorption isotherm at 77 K (using slit pore geometry). This DFT analysis is based on a library of calculation results derived from the adsorption of gases at various pore sizes and specific pore morphologies. PSD is calculated from experimental adsorption isotherms by solving the integral adsorption equation, which is represented as the convolution of a set of theoretical isotherms with respect to the aperture (DFT model kernel).

[0056] Micropore volume is the portion of the total pore volume attributable to micropores (i.e., pores smaller than approximately 2 nm). Total pore volume and micropore volume can be expressed as p / p... 0 =0.97 and p / p 0 =0.1, for example Figures 1 to 3 The nitrogen adsorption isotherm at 77 K shown was obtained by measurement. 0 It is the liquefaction pressure of N2 at 77K, which is approximately atmospheric pressure.

[0057] Brunauer-Emmett-Teller (BET) specific surface area (S) BET The surface area of ​​a solid per unit mass is measured by the physical adsorption of gas molecules. It can be calculated using the BET equation: ; in / It is relative pressure. It is the amount of gas adsorbed. It refers to the amount of gas adsorbed as a monolayer. This is the BET constant. It can then be plotted as a BET graph using experimental results (see examples), i.e. right The graph. The slope of the resulting straight line. and y-intercept The value can be used to calculate the weight of gas adsorbed in a monolayer using the following equation. and BET constant : ;and .

[0058] Total surface area Specific surface area of ​​BET It is given by the following formula: ;and .

[0059] Where N is Avogadro's constant; s It is the adsorption cross-sectional area of ​​the adsorbed species; V It is the molar volume of the adsorbate gas and a It refers to the mass of the solid / adsorbent.

[0060] Langmuir surface area is a measure of the surface area of ​​a solid by the physical adsorption of gas molecules. Langmuir-type isotherms correspond to p / p 0 The shaft is concave, and as... →1, the number of adsorbed molecules on a surface covered by a gas monolayer approaches a limiting value. The Langmuir adsorption isotherm equation can be described as follows: = θ = Where, θ = .

[0061] in K L It is a constant. P It's pressure. n m Monolayer capacity is defined as the amount of adsorbate required to cover a surface with a complete monolayer. n Under specific pressure P The amount of gas adsorbed below. Surface coverage ( θ) is defined as the amount of adsorbed substance (Γ) and the monolayer capacity (Γ). mon It is the ratio of the maximum adsorption capacity.

[0062] This invention stems from the desire to develop nanoporous materials for storing gases (e.g., hydrogen, oxygen, and / or nitrogen) under high pressure, in order to overcome one or more limitations associated with nanoporous materials proposed to date for similar purposes.

[0063] Storing gases under high pressure, such as pressures exceeding 40 bar; or exceeding 80 bar; or exceeding 100 bar; or exceeding 110 bar, and up to, for example, 180 bar, 200 bar, 250 bar, 300 bar, 500 bar, or 1000 bar, allows for the containment of increasingly larger quantities of gas in a given space. The effect of the materials described herein is to increase the amount of gas stored at a given pressure. This pressure can be the maximum pressure of the relevant gas containment system. This maximum pressure can be the nominal maximum pressure.

[0064] Pressure vessels used to store the gas of interest herein can be tested and certified to operate at nominal maximum pressures up to, for example, 700 bar. By using the materials described herein, for example, the amount of H2 loaded at 700 bar can be significantly increased. Alternatively, a predetermined amount of H2 can be stored at a reduced pressure. For example, the same amount of H2 stored in a pressure vessel at 250 bar can be stored at pressures far below 250 bar. This will affect the required pressure vessel wall thickness, which can be reduced. Assuming the pressure vessel comprises a composite structural layer containing expensive fibers (e.g., carbon fiber) and a thermosetting resin matrix, cost savings can be achieved by reducing the amount of fiber and matrix required. In turn, even a reduction in carbon fiber supply can make larger-scale H2 storage projects feasible.

[0065] The materials described herein have been experimentally tested under high-pressure operating conditions, providing confidence that they can achieve the expected results. The amount of “releasable” or “released” gas is an important parameter because it represents the difference between the amount of gas stored at the reference pressure and the amount of gas remaining stored at the desired release pressure. For H2, the release pressure can be from approximately 1 bar to 10 bar. Therefore, although metallic materials (such as MOFs) achieve maximum effective adsorption at low pressures, they may prove less practical in maximizing the amount of gas released between the reference and release pressures. The materials and methods described herein offer a weaker gas... Pore ​​wall interactions induce a moderate adsorption slope in the low-pressure range and maximize gas loading at high pressures. Using at least some of the materials and methods described herein, gas adsorption can be achieved in the pressure range of 80 bar to 180 bar and higher. This is particularly useful for H2 applications, but it should be understood that these materials and methods are equally likely to be effective in a wide range of other potential applications, such as for storing O2 and / or N2.

[0066] The materials described herein include high levels of porosity, and therefore possess high levels of specific surface area. These levels are achieved by using porous gas storage materials comprising a cross-linked polymer backbone. Therefore, this disclosure provides a method for storing gas, comprising: Provide a container for receiving the gas; A porous gas storage material is provided, the gas storage material comprising: Crosslinked polymer backbone; and Multiple pores for gas adsorption; The crosslinked polymer backbone comprises aromatic ring-containing monomer units, each of which comprises at least two aromatic rings, and wherein the aromatic ring-containing monomer units are directly connected by covalent crosslinking bonds between the aromatic rings. The container is designed to withstand a nominal maximum internal pressure P1 greater than atmospheric pressure. The porous gas storage material is disposed within or inside the container; and the gas is loaded into the container to a pressure P2, which is equal to or lower than P1.

[0067] P1 and P2 can each be significantly higher than atmospheric pressure. P2 can be equal to or greater than N bar, where N is an integer from 2 to 700. The container can be loaded to achieve an internal pressure P2 equal to or greater than approximately 15 bar, 35 bar, 40 bar, 80 bar, 100 bar, 120 bar, 150 bar, or 180 bar. Thus, the method is able to provide improved gas storage at or above the aforementioned pressures. The value of P1 can be as high as several hundred bar, for example, 700 bar.

[0068] The container may be a pressure vessel designed to store the gas described herein, or to store and transport the gas described herein.

[0069] Pressure vessels may include load-bearing structural components made of composite materials, optionally fibrous composite materials. The composite material may include thermosetting resins, optionally dicyclopentadiene (DCPD) resins, optionally with a purity of 92% or higher.

[0070] Pressure vessels may include a metal liner or a polymer liner for containing the gases described herein.

[0071] The following discussion of the gas storage materials disclosed herein is adapted, with necessary modifications, to apply to all aspects and embodiments of the invention described herein.

[0072] The crosslinked polymer backbone may include copolymers comprising two or more monomer units containing aromatic rings with different structures.

[0073] The crosslinked polymer backbone may include monomer units containing aromatic rings, said monomer units including at least three aromatic rings, optionally at least four aromatic rings, optionally at least five aromatic rings, or optionally at least six aromatic rings.

[0074] At least one subset of aromatic ring-containing monomer units may include at least four aromatic rings.

[0075] At least one subset of the monomer units containing aromatic rings or the monomer units of the copolymer may include two or more rings fused or linked in a conjugated system. Optionally, the fused rings are bicyclic, tricyclic, or polycyclic ring systems. Bicyclic, tricyclic, or polycyclic ring systems are preferably naphthyl, anthraceneyl, tetraphenyl, carbazolyl, indoleyl, isoindoleyl, indazoleyl, indeneyl, isoquinolinyl, quinazolinyl, or quinolinyl, preferably anthraceneyl, tetraphenyl, or carbazolyl. Optionally, the rings or fused rings may be linked to form a conjugated system or a larger aromatic ring (e.g., a macrocyclic aromatic ring, such as porphyrin).

[0076] Aromatic ring-containing monomer units can: a) Directly connected via covalent bonds between aromatic rings; or b) Linked by cross-linking portions between aromatic rings, wherein the cross-linking portions are optionally aliphatic groups, optionally alkylene groups (e.g., methylene).

[0077] The aromatic ring-containing monomer units and / or monomers of the present invention can be spatially extended molecules having multiple aromatic rings. These aromatic rings can be spaced apart from each other within the molecule itself. At least two of these aromatic rings can be disposed on the periphery. At least two of these aromatic rings can form at least a portion of the periphery of the monomer or monomer unit. The periphery of the monomer or monomer unit can be completely defined by these aromatic rings. At least two of these aromatic rings can be covalently linked to the remainder of the monomer or monomer unit. These monomers are selected to be non-stacking.

[0078] The aforementioned characteristics, individually or in combination with multiple possible reaction sites present on each aromatic ring, endow the monomer with an inherent tendency to branch and spatially extend into a porous cross-linked polymer network. At least a subset of the aromatic ring-containing monomer units may include two aromatic rings as described below: a) The spatial spacing between the two aromatic rings (e.g., measured from their respective centers) is at least 0.2 nm, optionally at least 0.3 nm, optionally at least 0.4 nm, optionally at least 0.5 nm, or optionally at least 0.6 nm, wherein the spatial spacing is measured from the centers of the aromatic rings; and / or b) The two aromatic rings are separated from each other by four or more bonds.

[0079] With respect to any selected atom (e.g., carbon, silicon, or nitrogen) contained in the aromatic ring-containing monomer or monomer unit, the aromatic ring-containing monomer or monomer unit may include a set of aromatic rings that share the atom or are directly connected to the atom. Regardless of the selected reference atom, the set of aromatic rings may include a maximum of three such aromatic rings. Regardless of the selected reference atom, the set of aromatic rings may include a maximum of two such aromatic rings.

[0080] Aromatic ring-containing monomer units can be derived from aromatic ring-containing monomers, each monomer including at least one aromatic ring that rotates freely relative to the rest of the monomer. This rotation can be achieved, for example, when the aromatic ring is covalently bonded to the monomer or the rest of the monomer unit. These freely rotating aromatic rings serve as attachment points for crosslinking with other monomer units within the crosslinked polymer. The fact that these aromatic rings can rotate freely out of plane relative to the rest of the monomer or monomer unit, and / or relative to one or more other aromatic rings of the monomer or monomer unit (i.e., they can be orthogonally oriented to adjacent portions) maximizes the chances of these aromatic rings crosslinking with other monomers or monomer units.

[0081] At least one subset of the aromatic ring-containing monomer units can be selected from the following group: .

[0082] The exemplary crosslinked polymer backbones described herein include, but are not limited to: homopolymers formed from monomer units directly connected by covalent bonds between aromatic rings; homopolymers formed from monomer units connected by alkylene linkages (preferably methylene linkages) between aromatic rings; and copolymers of the monomer units, optionally copolymers of monomer units directly connected by covalent bonds between aromatic rings.

[0083] In any aspect of this disclosure, the aromatic-ring-containing monomer or monomer unit may include an alkenyl group. Optionally, the aromatic-ring-containing monomer or monomer unit is stilbene, tristilbene, or tetrastilbene.

[0084] Porous gas storage materials can be amorphous. The tertiary structure of the cross-linked polymer backbone does not form a regular crystalline structure.

[0085] The BET specific surface area of ​​gas storage materials can be greater than approximately 750 m².2 g -1 Optional site greater than approximately 850m 2 g -1 Optional location greater than approximately 1000m 2 g -1 Optional site larger than approximately 1250m 2 g -1 Optional site larger than approximately 1500m 2 g -1 Optional location greater than approximately 2000m 2 g -1 Optional site greater than approximately 3000m 2 g -1 and optionally greater than about 4000m 2 g -1 The approximate term "approximately" refers to ±25m. 2 g -1 .

[0086] In a highly preferred embodiment, the pores in the gas storage material may include micropores. The gas storage material may include micropores of about 1 nm to about 2 nm, optionally about 1.0 nm to about 1.8 nm, or optionally about 1.2 nm to about 1.8 nm.

[0087] The total pore volume of gas storage materials can be greater than approximately 0.40 cm³. 3 g -1 Optional, larger than approximately 0.50cm 3 g -1 Optional, larger than approximately 0.60cm 3 g -1 Optional, larger than approximately 0.90cm 3 g -1 Optional, larger than approximately 1.00cm 3 g -1 Optional, larger than approximately 0.60cm 3 g -1 Optional, larger than approximately 1.20cm 3 g -1 Optional, larger than approximately 1.40cm 3 g -1 Optional, greater than approximately 1.50 ccm 3 g -1 Optional, larger than approximately 1.50cm 3 g -1 Optional, larger than approximately 2.00cm 3 g -1 Optional, larger than approximately 2.70cm 3 g -1 and optionally larger than about 3.00cm 3 g-1 The approximate term "approximately" refers to ±5% of the corresponding value.

[0088] The ratio of micropore volume to total pore volume can be greater than approximately 0.30 cm³. 3 g -1 Optional, larger than approximately 0.40cm 3 g -1 Optional, larger than approximately 0.50cm 3 g -1 Optional, larger than approximately 0.60cm 3 g -1 and optionally larger than about 0.70cm 3 g -1 The estimated value of the term "approximately" can be approximately ±8% of the corresponding numerical value.

[0089] In any aspect of this disclosure as described herein, the crosslinked polymer can be a highly crosslinked polymer.

[0090] A wide variety of highly absorbent materials can be prepared using the methods described herein, based on the gas storage materials described herein. These methods directly utilize commercially available and sometimes inexpensive unsubstituted aromatic molecules as precursors, enabling simple processing. This approach allows for the scaling up of reactions from laboratory scale to larger scales, particularly to industrial-scale production.

[0091] In another aspect, this disclosure provides a method for preparing porous gas storage materials, wherein the method includes: Provides a monomer containing aromatic rings, said monomer comprising at least two aromatic rings; and This allows monomers to undergo metal-catalyzed cross-coupling reactions; A gas storage material is formed comprising a cross-linked polymer backbone having aromatic ring-containing monomer units and including multiple micropores for gas adsorption, wherein the aromatic ring-containing monomer units are directly linked by covalent bonds between the aromatic rings. The cross-coupling reaction can be carried out using a nickel catalyst or a palladium catalyst. The method includes a nickel-catalyzed cross-coupling reaction, optionally a Yamamoto cross-coupling reaction. The method can be implemented as a step in which the monomer is combined with a cross-coupling agent to directly form a cross-linked polymer.

[0092] As an alternative, the Fried-Krawc alkylation reaction has been used to obtain industrial products for over a century and has thus proven robust and reliable for large-scale production. This is a prerequisite for large-scale capture and storage of hydrogen, oxygen, and / or nitrogen. In some methods, the reaction introduces short methylene (CH2) bridges between monomers. Each monomer unit forms multiple bridges, thereby constructing the aforementioned porous and rigid network. These materials and methods provide a suitable wall-pore balance for high-pressure gas storage.

[0093] Therefore, in another aspect, this disclosure provides a method for preparing porous gas storage materials, wherein the method includes: Provides a monomer containing aromatic rings, said monomer comprising at least two aromatic rings; and The monomers are crosslinked via Fried-Krawtz alkylation. To form a gas storage material, the gas storage material comprising a cross-linked polymer backbone having aromatic ring-containing monomer units and including a plurality of pores for gas adsorption, wherein the aromatic ring-containing monomer units are linked by cross-linked portions (optionally aliphatic groups, such as alkyl groups) between aromatic rings. The at least one subset of the aromatic ring-containing monomer unit comprises at least five aromatic rings, optionally the at least one subset of the aromatic ring-containing monomer unit comprises a carbazole group or a porphyrin group; or At least one subset of the aromatic ring-containing monomer units is selected from the group consisting of: .

[0094] In some cases, the crosslinked portion is methylene. Fried-Krawc alkylation involves alkylating an aromatic ring with an alkylating agent (an electrophilic agent in the reaction that forms the crosslinked portion) under acidic conditions (Lewis acid catalysts, such as TiCl4, BF3, SnCl4, FeCl3, and AlCl3 or Brønsted acids). The alkylating agent can be an alkyl halide or an acetal, i.e., an alkyl group substituted with a leaving group. The alkylating agent is preferably bifunctional or polyfunctional, i.e., it includes two or more leaving groups, and thus can form crosslinks between two or more aromatic rings. The method may include crosslinking the monomer via a Fried-Krawc alkylation reaction using dimethylformaldehyde (FDA) and optionally ferric chloride (III) as a catalyst or under acidic conditions. The method may be carried out as a step in which the monomer is combined with the alkylating agent to directly form a crosslinked polymer.

[0095] In another aspect, this disclosure provides a porous gas storage material, the porous gas storage material comprising: Crosslinked polymer backbone; and Multiple pores for gas adsorption; The crosslinked polymer backbone comprises aromatic ring-containing monomer units, each of which comprises at least two aromatic rings, and wherein the aromatic ring-containing monomer units are directly connected by covalent bonds between the aromatic rings.

[0096] In another aspect, this disclosure provides a porous gas storage material, the porous gas storage material comprising: Crosslinked polymer backbone; and Multiple pores for gas adsorption; The crosslinked polymer backbone comprises aromatic ring-containing monomer units, each monomer unit comprising at least two aromatic rings, and wherein the aromatic ring-containing monomer units are linked by crosslinking portions (optionally aliphatic groups, such as alkyl groups) between the aromatic rings; and The at least one subset of the aromatic ring-containing monomer unit comprises at least five aromatic rings, optionally the at least one subset of the aromatic ring-containing monomer unit comprises a carbazole group or a porphyrin group; or At least one subset of the aromatic ring-containing monomer units is selected from the group consisting of: .

[0097] On the other hand, this disclosure provides gas storage materials described herein for storing gases at pressures above atmospheric pressure. Optionally, the gas storage material is used to store gases at pressures greater than N bar, where N is an integer from 2 bar to 700 bar. Optionally, the gas storage material is used to store gases at pressures greater than about 15 bar, 35 bar, 40 bar, 80 bar, 100 bar, 120 bar, 150 bar, or 180 bar. The gas may include H2, O2, and / or N2.

[0098] In a seventh aspect, this disclosure provides the use of the gas storage material described herein for storing gases at pressures above atmospheric pressure. Optionally, the gas storage material is used for storing gases at pressures greater than N bar, where N is an integer from 2 bar to 700 bar. Optionally, the gas storage material is used for storing gases at pressures greater than about 15 bar, 35 bar, 40 bar, 80 bar, 100 bar, 120 bar, 150 bar, 180 bar, or 500 bar. The gas may include H2, O2, and / or N2.

[0099] The embodiments described herein with respect to any aspect of this disclosure may be adapted to other aspects of this disclosure with necessary modifications.

[0100] Example The following embodiments illustrate implementations of the invention in a non-limiting manner.

[0101] The examples described below illustrate the synthesis of various materials comprising crosslinked polymers from pre-synthesized aromatic monomers. The pre-synthesized aromatic monomers can be prepared using any standard organic synthesis method in the art.

[0102] BIC-1 was synthesized via Fried-Krawc alkylation reaction.

[0103] Tri-disperse spirodifluorene In a Schlenk tube, under an inert atmosphere (dry nitrogen), dimethylformaldehyde (FDA) (0.8 mL, 9.042 mmol) was added to a solution of 1,2-dichloroethane (DCE) (40 mL) containing tripterene (501.6 mg, 1.972 mmol) and spirodifluorene (468.6 mg, 1.481 mmol). The ratio of the two monomers was 4:3. The Schlenk tube was placed in an ice bath and cooled to 0 °C, and Brønsted acid (BA) (62.3 mmol) was added dropwise to the reaction system. The mixture was brought to 25 °C and stirred for 72 hours. After the reaction was complete, the resulting powder was collected by filtration, washed with EtOH, H2O, and CHCl3, and then dried in air overnight. The solution was then dried under vacuum (p=1). 10 -4 Dry at 85°C for 24 hours under high vacuum (p=3) 10 -6 Dry at 120°C for 12 hours to remove solvent.

[0104] BIC-2 was synthesized via the Yamamoto cross-coupling reaction.

[0105] Tris(4-bromophenyl)methanes, tetra(4-bromophenyl)methane In a two-necked round-bottom flask under a dry nitrogen atmosphere, 1.1 g of 2,2'-bipyridine was dissolved in anhydrous DMF (175 mL) and freshly distilled THF (60 mL) to form a purple solution in the presence of 1,5-cyclooctadiene (1.1 mL) and bis(1,5-cyclooctadiene)nickel (0) (2 g). Two monomers, tris(4-bromophenyl)methane (X = hydrogen or alkyl) and tetra(4-bromophenyl)methane (molar ratio 1:3), were dissolved in 60 mL of THF and then added dropwise to the flask at room temperature. The addition process lasted for one hour in total. The solution was stirred for 48 hours and then quenched with 30 mL of HCl, producing a green / light blue suspension. After 4 hours, the white solid was filtered off, washed with THF, water, and dichloromethane, and dried in air overnight. Finally, the product was heated at 150 °C under vacuum for 24 hours.

[0106] BIC-3 was synthesized via Fried-Krafts alkylation reaction.

[0107] Triptenetetraphenylmethane In a Schlenk tube, under an inert atmosphere (dry nitrogen), dimethylformaldehyde (FDA) (0.8 mL, 9.042 mmol) was added to a solution of 1,2-dichloroethane (DCE) (40 mL) containing tripterene (501.2 mg, 1.971 mmol) and tetraphenylmethane (474.1 mg, 1.480 mmol). The ratio of the two monomers was 4:3. The Schlenk tube was placed in an ice bath and cooled to 0 °C, and Brønsted acid (BA) (62.3 mmol) was added dropwise to the reaction system. The mixture was brought to 25 °C and stirred for 72 hours. After the reaction was complete, the resulting powder was collected by filtration, washed with EtOH, H2O, and CHCl3, and then dried in air overnight. The solution was then dried under vacuum (p=1). 10 -4 Dry at 85°C for 24 hours under high vacuum (p=3) 10 -6 Dry at 120°C for 12 hours to remove solvent.

[0108] Table 1: Elemental Analysis

[0109] Calculation of surface area and pore volume of porous gas storage materials Surface area (m²) 2 / g) Calculated from the nitrogen adsorption branch of the nitrogen adsorption isotherm at 77 K according to the Brunauer-Emmett-Teller (BET) and Langmuir models. Total pore volume, V tot (cm 3 / g) by p / p 0 The nitrogen isotherm calculation is performed at p = 0.97. The micropore volume (i.e., the portion of the total pore volume provided by micropores) is calculated according to the IUPAC definition as the amount of pores with a pore width less than 20 Å. The ratio of micropore volume to total pore volume (labeled "micropore / total pore volume" in the table below) is calculated as the micropore volume (pores with a pore width less than 20 Å) and the value at p / p 0 =0.97, the ratio of total pore volume (pores with a width less than 500 Å) calculated at a value of 0.97. Thermal stability is determined by thermogravimetric analysis (see...). Figure 1 C Figure 2 C and Figure 3 C) Calculations were performed, with weight loss measured at 600°C.

[0110] Table 2: Surface area (m²) of BET and Langmuir models2 / g), total pore volume (m 3 (g), micropore / total pore volume, thermal stability (°C), and weight loss (%).

[0111]

[0112] High-pressure hydrogen adsorption isotherm ( Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 ) After the experiment, the isotherms were corrected for blank conditions. The blank experiment was obtained by a point-to-point method using two cycles on an empty tank. Having demonstrated the high-pressure performance of the novel material, it is conceivable that a large number of molecules containing benzene rings and other aromatic rings are suitable as precursors to form efficient nanoporous materials for loading high-pressure hydrogen via Fried-Krawz or cross-coupling methods (e.g., Yamamoto-type catalysis). These materials provide aromatic ring-containing monomers comprising at least two aromatic rings; and cross-linked copolymer monomers are cross-linked via Fried-Krawz alkylation or cross-coupling reactions to form gas storage materials comprising a cross-linked copolymer backbone and multiple pores for gas adsorption. This cross-linked copolymer backbone has aromatic ring-containing comonomer units linked by cross-linked portions (optionally aliphatic groups, such as alkyl groups) or by direct C-C bonds between aromatic rings.

[0113] Before analysis, the sample was directly placed in a steel container under vacuum at 100°C (p=3). 10 -6 Activation was performed overnight at 77 K and 195 K. Adsorption up to 100 bar was carried out in each experiment. Desorption cycle. Temperature is controlled using an optional cryogenic kit. Before hydrogen adsorption measurements, the background free space volume and analytical free space volume of the empty sample tube are measured twice with helium, and then manually entered during experimental resolution. After analysis, the physical volume of the sample is determined using its mass and density (measured via a helium specific gravity bottle). The sample volume is then subtracted from the initial background and analytical free space values ​​entered into the software to correct the blank sample tube free space value according to the sample volume.

[0114] High-pressure hydrogen adsorption measurements were performed to test the maximum gas capacity and determine the isotherm profile from low to high pressure. High-pressure H2 adsorption isotherms up to 100 bar were collected using a volumetric adsorption instrument. The sample was loaded into a 2 mL steel container. Glass beads were used to minimize the empty volume within the sample container.

[0115] The resulting isotherm is an "excess" isotherm, representing the excess gas "adsorbed" by the sample due to its pore sites. However, under high pressure, the gas density exceeds the ideal gas range, and this must be considered during experimental analysis. The "total" adsorption amount (n...) tot The excess adsorption is defined as the sum of the total accessible gas volume of the system, V, which would occupy the system even without any adsorption occurring. p The amount of H2,

[0116] This relationship applies, where ρ(P) is the hydrogen density as a function of pressure: The hydrogen adsorption isotherm is shown below ("total" adsorption amount vs. pressure).

[0117] To avoid errors caused by sample contamination between the degassing and measurement stages, the sample mass is measured after analysis.

[0118] Solid-state nuclear magnetic resonance (SS NMR) 13 C-C-MAS NMR spectrum ( Figure 10 B Figure 11 B and Figure 12 B) confirmed the chemical structure of the skeleton, highlighting the presence of two comonomer units and crosslinked portions in samples obtained by Fried-Krawc alkylation, or the formation of direct C-C bonds in samples synthesized by cross-coupling reactions.

[0119] Table 3: BIC-1 13 C NMR resonance attribution.

[0120]

[0121] Table 4: BIC-2 13 C NMR resonance attribution.

[0122]

[0123] Table 5: BIC-3 13 C NMR resonance attribution.

[0124]

[0125] Skeletal density (helium specific gravity bottle method) Table 6: Skeletal Density

[0126] Material density

[0127] Table 7: Density of porous materials.

[0128]

[0129] Example: H2 adsorption measurement up to 100 bar High-pressure H2 adsorption measurements were performed to test the maximum gas capacity and determine the isotherm profile from low to high pressure (i.e., a wider range than previously achieved by existing technologies). This allows for the determination of the material's 'release gas' potential.

[0130] The experiment was conducted using the Micromeritics HPVAII (High Pressure Volumetric Method Test Apparatus), which is equipped with a booster compressor. The booster compressor is used to compress the gas in the cylinder to a maximum of 100 bar.

[0131] The sample was loaded into a 10 mL steel can and connected to the instrument via a VCR connector. The connector was fitted with a 10 μm sealing sintered gasket to prevent the sample from diffusing into the manifold volume.

[0132] Before analysis, the sample was activated overnight in a steel tank under vacuum at 130°C.

[0133] Each experiment was performed at 25°C with an adsorption capacity of up to 100 bar. Desorption cycle. Temperature is controlled via a Julabo F12-ED cooling / heating circulator connected to the HPVA circulating Dewar flask. The free space volume is measured with helium before the first run and then manually entered during experimental analysis.

[0134] To avoid errors caused by sample contamination between the degassing and measurement stages, sample mass is measured after analysis.

[0135] After the experiment, the isotherms were corrected for blank conditions. The blank experiment was obtained by a point-to-point method using five cycles performed on an empty tank.

[0136] The resulting isotherm is an "excess" isotherm, representing the excess gas "adsorbed" by the sample due to the active pore surface. At pressures exceeding 10 bar, the gas density exceeds the ideal gas range, and this must be considered during experimental analysis. To obtain the "total" adsorption amount (n... tot The total pore volume of the sample (V) must be taken into account. p The ratio between the volume of an ideal gas and the volume occupied by the same amount of gas at a specific pressure (ρ(P)) follows the following relationship:

[0137] In this analytical process, to obtain the function ρ(P), the H2 density values ​​at pressures ranging from 0.5 bar to 200 bar were fitted with a polynomial function, and then calculated point-by-point using the pressure at each analysis point. The density values ​​were obtained using the REFPROP software from the NIST database.

[0138] The H2 adsorption isotherms of the materials described in this article are shown in the following figures: Figures 4 to 9 In the figure, the desorption branch almost overlaps with the adsorption branch. The "wt%" in the figure represents the percentage of adsorbed H2 mass relative to the mass of the porous material.

[0139] Having demonstrated the high-pressure performance of the novel material, it is conceivable that a large number of molecules containing benzene rings and other aromatic rings are suitable as precursors to form efficient nanoporous materials via Friedel-Crafts or cross-coupling methods (e.g., Yamamoto-type catalysis). These materials can be used to load hydrogen, oxygen, and / or nitrogen at high to high pressures. Acetylene moieties can also be inserted as structural extenders, for example, to obtain better performance. In other instances, fluorinated compounds can be used to achieve tunable adsorption capacities from high to low pressures.

[0140] In other words, the aromatic ring-containing monomers constituting the crosslinked polymer backbone are designed to have a suitable shape that hinders favorable bonding with adjacent monomers. This principle is systematically applied to prevent aggregation between molecular precursors during backbone formation: carbon The formation of carbon bonds (or alkyl bridging, such as methylene CH2) fixes the molecular building blocks and imparts rigidity, placing them in this loosely packed arrangement. To prevent the structure from collapsing into a more compact arrangement through conformational relaxation, aromatic ring-containing monomer units with suitable structural rigidity are employed. Aromatic ring-containing monomers contain multiple aromatic rings (especially the typical six-membered rings of benzene and its derivatives). These rings exhibit excellent stability and include electron densities that promote interactions with hydrogen atoms. The multiple reactive sites on the aromatic rings also provide a tendency for 3D branching and structural spatial development.

[0141] at last, Figures 13 to 16 Taking BIC-1 and BIC-2 as examples, the expected performance curves at 77K and 195K are shown. The results not only cover the experimental storage pressure range (0 bar to 100 bar), but also extend the pressure to 250 bar and 700 bar using extrapolation methods based on the two-site Langmuir equation or the Langmuir-Freundlich equation. Figure 13 A shows BIC 1. Experimental hydrogen adsorption isotherms up to 250 bar (in wt%), including experimental data up to 100 bar and extrapolated data up to 250 bar obtained using the two-site Langmuir equation. Figure 13 B indicates BIC 2. Hydrogen adsorption isotherms up to 700 bar (wt%), including experimental data up to 100 bar and extrapolated data up to 700 bar obtained using the two-site Langmuir equation. More details are reported in the table below.

[0142] Table 8: Total adsorption capacity of BIC-1 at 77 K, including experimental data up to 100 bar and extrapolated data up to 700 bar obtained using the two-site Langmuir equation.

[0143]

[0144] Figure 14 and Figure 13 Similar, but its corresponding BIC 1. Test results at 195K. Further details related to the fitting of the Langmuir Freundlich equation are also described in the table below.

[0145] Table 9: Total adsorption capacity of BIC-1 at 195 K, including experimental data up to 100 bar and extrapolated data up to 700 bar obtained using the Langmuir-Freundlich equation.

[0146]

[0147] Figure 15 and Figure 13 Similar, but its corresponding BIC 2. Test results at 77K. Further details regarding the fitting of the Langmuir Freundlich equation are also described in the table below.

[0148] Table 10: Total adsorption capacity of BIC-2 at 77 K, including experimental data up to 100 bar and extrapolated data up to 700 bar obtained using the Langmuir-Freundlich equation.

[0149]

[0150] Figure 16 and Figure 13 Similar, but its corresponding BIC 2. Test results at 195K. Further details regarding the fitting of the Langmuir Freundlich equation are also described in the table below.

[0151] Table 11: Total adsorption capacity of BIC-2 at 195 K, including experimental data up to 100 bar and extrapolated data up to 700 bar obtained using the two-site Langmuir equation.

[0152]

[0153] Particles of a cross-linked polymer backbone can be stably aggregated using a binder to prepare materials that can be molded into macroscopic objects. This process can be achieved using a small amount of binder, typically 2% to 15% by weight. The binder can be selected from inorganic and organic materials, including hydrophilic or hydrophobic linear polymers and copolymers, such as polyvinyl alcohol and polyvinylidene fluoride.

[0154] Using the aforementioned macroscopic objects can improve several material performance indicators, including container loading speed and gas diffusion capacity.

[0155] The methods for preparing the gas storage materials described herein may include metal-catalyzed cross-coupling reactions to form gas storage materials, typically employing pre-prepared Ni(1,5-COD)₂ (COD = cyclooctadiene) complexes with 2,2'-... Bipyridine is used as a catalyst; or alternatively, NiX2 (X is a halogen, preferably chlorine or bromine), a reducing metal (preferably zinc or magnesium), COD, and 2,2'- The catalyst is formed in situ using bipyridine.

[0156] Compared to compressed gases that do not use the storage materials described herein, the storage methods described herein offer various operational safety advantages for the containment of H2, whether in static containers (stationary containers) or in transport applications.

[0157] For the same amount of H2 stored or transported: 1) The pressure inside the container is significantly lower, so the safety specifications for the container can be lower; or in any case, it can allow for wider application and compliance with any legal restrictions on use; 2) When a container leaks, the outflow time of H2 is slower due to the lower pressure and slower diffusion through the pores within and between material particles.

[0158] Embodiments of the present invention have been described by way of example only. It should be understood that variations can be made to the described embodiments while still falling within the scope of the present invention. In particular, it can also be applied to gases other than hydrogen, as long as the molecular size of the adsorbed gas allows it to enter the pores of the adsorbent material.

Claims

1. A method for preparing a porous gas storage material for storing hydrogen and / or oxygen and / or nitrogen, wherein the method comprises: Provides a monomer containing aromatic rings, said monomer comprising at least two aromatic rings; as well as The monomer is subjected to a metal-catalyzed cross-coupling reaction to form a gas storage material comprising a cross-linked polymer backbone and including a plurality of pores for gas adsorption, the cross-linked polymer backbone having aromatic ring-containing monomer units directly connected by covalent bonds between aromatic rings.

2. The method according to claim 1, wherein the crosslinked polymer backbone: Includes a monomer unit containing aromatic rings, wherein the monomer unit includes at least three aromatic rings, optionally at least four aromatic rings, optionally at least five aromatic rings, or optionally at least six aromatic rings; or, Includes copolymers, said copolymers comprising two or more monomer units containing aromatic rings with different structures; or, The at least one subset of the aromatic ring-containing monomer units comprises at least four aromatic rings; or, The aromatic ring-containing monomer unit or at least a subset of the monomer units of the copolymer comprises two or more aromatic rings fused or connected in a conjugated system; or, At least one subset of the aromatic ring-containing monomer units comprises two aromatic rings as described below: a) The center-to-center spatial spacing between the two aromatic rings is at least 0.2 nm, optionally at least 0.3 nm, optionally at least 0.4 nm, optionally at least 0.5 nm, optionally at least 0.6 nm, optionally at least 0.7 nm, and optionally at least 0.8 nm; and / or c) The two aromatic rings are separated from each other by four or more bonds; or, in, At least one subset of the aromatic ring-containing monomer units is selected from the group consisting of: 。 3. The method according to claim 1 or 2, wherein the method comprises a nickel-catalyzed cross-coupling reaction, optionally a Yamamoto cross-coupling reaction.

4. The method according to claim 1, 2 or 3, wherein the metal-catalyzed cross-coupling reaction uses a pre-prepared Ni(1,5-cyclooctadiene)2 complex together with 2,2'-bipyridine as a catalyst.

5. The method according to claim 1, 2 or 3, wherein the metal-catalyzed cross-coupling reaction comprises forming a catalyst in situ with NiX2, a reducing metal, cyclooctadiene and 2,2'-bipyridine, wherein X is a halogen.

6. The method according to claim 5, wherein the reducing metal is magnesium or zinc.

7. The method according to claim 5 or 6, wherein X is chlorine or bromine.

8. A method for preparing a porous gas storage material for storing hydrogen and / or oxygen and / or nitrogen, wherein the method comprises: Provides a monomer containing aromatic rings, said monomer comprising at least two aromatic rings; as well as The monomer is crosslinked via a Fried-Krawc alkylation reaction to form a gas storage material comprising a crosslinked polymer backbone and including a plurality of pores for gas adsorption. The crosslinked polymer backbone has aromatic ring-containing monomer units linked by crosslinking portions (optionally aliphatic groups, e.g., alkyl groups) between aromatic rings, wherein at least a subset of the aromatic ring-containing monomer units comprises at least five aromatic rings; or wherein at least a subset of the aromatic ring-containing monomer units is selected from the group consisting of: 。 9. The method of claim 8, wherein the method comprises using dimethylformaldehyde (FDA) and optionally ferric chloride (III) as a catalyst or acidic conditions to crosslink the monomer via a Fried-Krawc alkylation reaction.

10. The method according to any one of claims 1 to 9, wherein the gas storage material is an amorphous material.

11. The method according to any one of claims 1 to 10, wherein the BET specific surface area of ​​the gas storage material is greater than about 750 m². 2 g -1 Optional site greater than approximately 850m 2 g -1 Optional location greater than approximately 1000m 2 g -1 Optional site larger than approximately 1250m 2 g -1 Optional site larger than approximately 1500m 2 g -1 Optional location greater than approximately 2000m 2 g -1 Optional location greater than approximately 3000m 2 g -1 and optionally greater than about 4000m 2 g -1 .

12. The method according to any one of claims 1 to 11, wherein the pores in the gas storage material comprise micropores.

13. The method according to any one of claims 1 to 12, wherein the pore volume of the gas storage material is greater than about 0.40 cm³. 3 g -1 Optional, larger than approximately 0.50cm 3 g -1 Optional, larger than approximately 0.60cm 3 g -1 Optional, larger than approximately 0.90cm 3 g -1 Optional, larger than approximately 1.00cm 3 g -1 Optional, larger than approximately 0.60cm 3 g -1 Optional, larger than approximately 1.20cm 3 g -1 Optional, larger than approximately 1.40cm 3 g -1 Optional, larger than approximately 1.50cm 3 g -1 Optional, larger than approximately 2.00cm 3 g -1 Optional, larger than approximately 2.70cm 3 g -1 And optionally larger than about 3.00cm 3 g -1 .

14. A porous gas storage material for storing hydrogen and / or oxygen and / or nitrogen, comprising: Cross-linked polymer backbone; and Multiple pores for gas adsorption, wherein the cross-linked polymer backbone comprises aromatic ring-containing monomer units, wherein the aromatic ring-containing monomer units comprise at least two aromatic rings, and wherein the aromatic ring-containing monomer units are directly connected by covalent bonds between the aromatic rings.

15. The gas storage material of claim 14, wherein the cross-linked polymer backbone is as defined in claim 2.

16. A porous gas storage material for storing hydrogen and / or oxygen and / or nitrogen, comprising: Cross-linked polymer backbone; and Multiple pores for gas adsorption, wherein the crosslinked polymer backbone comprises aromatic ring-containing monomer units, each aromatic ring-containing monomer unit comprising at least two aromatic rings, and wherein the aromatic ring-containing monomer units are linked by crosslinking portions (optionally aliphatic groups, e.g., alkyl groups) between the aromatic rings, and wherein at least one subset of the aromatic ring-containing monomer units comprises at least five aromatic rings; or wherein at least one subset of the aromatic ring-containing monomer units is selected from the group consisting of: 。 17. The gas storage material according to any one of claims 14 to 16, wherein the gas storage material is an amorphous material.

18. The gas storage material according to any one of claims 14 to 17, wherein the BET specific surface area of ​​the gas storage material is greater than about 750 m². 2 g -1 Optional site greater than approximately 850m 2 g -1 Optional location greater than approximately 1000m 2 g -1 Optional site larger than approximately 1250m 2 g -1 Optional site larger than approximately 1500m 2 g -1 Optional location greater than approximately 2000m 2 g -1 Optional location greater than approximately 3000m 2 g -1 and optionally greater than about 4000m 2 g -1 .

19. The gas storage material according to any one of claims 14 to 18, wherein the pores comprise micropores.

20. The gas storage material according to any one of claims 14 to 19, wherein the pore volume of the gas storage material is greater than about 0.40 cm³. 3 g -1 Optional, larger than approximately 0.50cm 3 g -1 Optional, larger than approximately 0.60cm 3 g -1 Optional, larger than approximately 0.90cm 3 g -1 Optional, larger than approximately 1.00cm 3 g -1 Optional, larger than approximately 0.60cm 3 g -1 Optional, larger than approximately 1.20cm 3 g -1 Optional, larger than approximately 1.40cm 3 g -1 Optional, larger than approximately 1.50cm 3 g -1 Optional, larger than approximately 2.00cm 3 g -1 Optional, larger than approximately 2.70cm 3 g -1 And optionally larger than about 3.00cm 3 g -1 .

21. The porous gas storage material according to any one of claims 14 to 20, further comprising an adhesive, wherein, The porous gas storage material forms one or more macroscopic objects by being aggregated by the adhesive through the cross-linked polymer backbone.

22. The porous gas storage material according to claim 21, wherein the adhesive is 2% to 15% by weight of the porous gas storage material.

23. The porous gas storage material according to claim 21 or 22, wherein the adhesive comprises a hydrophilic or hydrophobic linear polymer or copolymer.

24. The porous gas storage material according to claim 21, 22 or 23, wherein the adhesive comprises polyvinyl alcohol or polyvinylidene fluoride.

25. Use of the porous gas storage material according to any one of claims 14 to 24 for storing gases including hydrogen and / or oxygen and / or nitrogen at pressures above atmospheric pressure.

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