Modified metal-organic frame (MOF) composition, method for producing the same, and method for using the same

Abstract

To provide modified metal-organic framework (MOF) materials, methods of preparing the same, and processes using the same.SOLUTION: A modified MOF of the invention is modified by impregnating a MOF with an inorganic metal salt. The starting MOF comprises at least one linker or ligand, which comprises an aryl amino group as part of its structure. The modified MOF is able to adsorb either basic or acidic toxic industrial compounds (TICs). The modified MOF can be used to remove TICs from various gaseous streams such as air.SELECTED DRAWING: None

Description

Technical Field

[0001] Description of Federally Sponsored Research or Development This invention was made with government support under Contract No. W911SR18C0031 awarded by the U.S. Army Combat Capabilities Development Command Chemical Biological Center (CCDC CBC) and Contract No. DE-SC0019959 awarded by the Department of Energy. The government has certain rights in this invention. Cross - Reference to Related Applications

[0002] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 003,260, filed Mar. 30, 2020, and U.S. Provisional Patent Application No. 63 / 055,737, filed Jul. 23, 2020. Technical Field

[0003] The present invention relates to a metal - organic framework (MOF) composition having at least one linker molecule with an arylamino group. This MOF has also been treated with a metal salt solution after synthesis. The present invention further relates to a process (method) for the preparation and activation of the modified MOF composition, and a process (method) for using the MOF composition to remove either basic or acidic toxic industrial compounds (TICs) from a gas stream.

Background Art

[0004] Adsorbents are well-known and used in many applications, including air filtration and gas supply. One specific application of adsorbents is the removal or reduction of contaminants in various gas streams, particularly the removal of toxic industrial compounds (TICs) present in airstreams. TICs can be classified as either basic or base-forming compounds, or acidic or acid-forming compounds. Adsorbents typically exhibit adsorption capacity for various TICs. However, the adsorption capacity for each TIC depends on the properties of the adsorbent, so many materials are excellent at adsorbing one TIC but unsuitable for adsorbing multiple TICs. For example, the MOF adsorbent Zr(NH2-BDC) has been shown to exhibit good adsorption capacity for NO2 but only slight adsorption capacity for ammonia. Filters that need to remove multiple TICs are routinely required in a wide range of industrial sectors. These technologies typically use multiple adsorbents. That is, the capacity for one TIC may be sufficient to remove a target TIC in a particular gas stream, but not sufficient to remove another TIC in the same gas stream. Therefore, multiple adsorbents are needed to remove two or more TICs from a gaseous stream such as air. Thus, there is a need for adsorbents that can effectively remove or reduce two or more TICs. We describe herein a group of adsorbents capable of removing multiple TICs from a gaseous stream in high capacity. More specifically, we need MOFs that can remove both basic and acidic TICs.

[0005] The applicant has developed a group of modified MOF materials that enhance the adsorption capacity for basic compounds such as ammonia while maintaining good adsorption capacity for acidic compounds such as nitrogen dioxide or chlorine. The remarkable aspect of the present invention is that when the adsorption capacity for basic compounds is enhanced by modifying the MOF, the adsorption capacity for acidic gases does not substantially decrease compared to the unmodified MOF. MOF materials capable of adsorbing both acidic and basic gaseous compounds are prepared by extracting a synthetic MOF that has good adsorption properties for acidic compounds, impregnating it in a metal salt solution, and then activating it.

[0006] US2019 / 0091503 discloses that metal-organic frameworks (MOFs) such as UiO-66 can be impregnated with metal compounds such as metal hydroxides or metal hydrides, and the metal compounds can be dispersed on the surface or in the pores of the MOF. According to the '503 publication application, these impregnated metal compounds are said to have catalytic properties that can destroy chemical weapons agents (CWAs) such as sarin. The MOF disclosed in the '503 application differs from the MOF of the present invention in that the MOF of the present invention has the ability to adsorb both basic and acidic TICs. [Overview of the project]

[0007] One embodiment of the present invention comprises a MOF comprising a corner metal unit in which metal (M) is selected from Zr, V, Al, Fe, Cr, Ti, Hf, Cu, Zn, Ni, Hf, In, Ce, and mixtures thereof, and a linker molecule that links the metal ion atoms, and an inorganic salt of metal (M') impregnated in the MOF, wherein the linker molecule comprises at least one organic ligand containing an arylamino group, or at least one organic ligand containing an arylamino group and at least one that does not contain an arylamino group A modified metal-organic framework (MOF) composition is characterized by being selected from combinations with an organic ligand, where the metal (M') is selected from Li, Na, K, Mg, Ca, Sr, Ba, Mn, Sc, Y, Ti, Zr, Hf, V, Cr, Mo, W, Fe, Co, Ni, Cu, Ag, Zn, Cd, Al, Ga, In, Sn, Pb, and mixtures thereof, having a static ammonia capacity of at least 4 mmol / g as measured at 10 Torr and 25°C, and substantially retaining its capacity for acidic TIC.

[0008] Further embodiments include cases where the M' inorganic salt is selected from halides, sulfates, carbonates, nitrates, or mixtures thereof. A particular embodiment is when the salt is a halide salt.

[0009] In yet another embodiment, the M' metal is present as a metal in an amount of approximately 0.25 wt.% to approximately 30 wt.%.

[0010] Another embodiment of the present invention is when the M metal is selected from Zr, Al, Fe, Cu, or Zn.

[0011] In yet another embodiment, at least one organic ligand containing an arylamino group is selected from 2-aminobenzene-1,4-dicarboxylic acid (NH2-BDC), 5-aminoisophthalic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, and mixtures thereof.

[0012] A further embodiment is when at least one organic ligand that does not contain an arylamino group is selected from terephthalic acid (BDC), isophthalic acid, benzoic acid, trimesic acid, acrylic acid, and mixtures thereof.

[0013] Another embodiment is when the M' metal is selected from Cu, Zn, Ni, Mn, Mg, or Ca.

[0014] In specific embodiments, the unmodified MOFs disclosed herein are selected from Zr-UiO-66-NH2, Ce-UiO-66-NH2, Hf-UiO-66-NH2, Fe-MIL-101-NH2, Al-MIL-53-NH2, Cr-MIL-101-NH2, Zn-IROM-3, Cu-BTC-NH2, Ti-MIL-125-NH2, In-MIL-86-NH2, and mixtures thereof.

[0015] Another embodiment is a process for preparing a metal-organic framework (MOF) composition, which includes the following: a. To form a reaction mixture comprising a metal compound selected from Zr, V, Al, Fe, Cr, Ti, Hf, Cu, Zn, Ni, Ce and mixtures thereof, and a ligand selected from at least one organic ligand containing an amino group or a combination of at least one organic ligand containing an amino group and at least one organic ligand not containing an amino group. b. Reacting a reaction mixture at a certain temperature and time to form an MOF. c. Separate the MOF and provide the MOF powder. d. Optionally, wash the MOF with an acid selected from formic acid, hydrochloric acid, nitric acid, sulfuric acid, and mixtures thereof to provide an MOF having free amines. e. Optionally, forming MOF powder into a molded body; and f. Impregnate the MOF molded body with an inorganic metal salt (M').

[0016] When a step of forming the MOF powder into a molded body is used, the impregnation step can be performed before, during, or after the step of forming the molded body. When a step of washing the MOF with acid is used, the acid washing is preferably performed before the impregnation step.

[0017] Embodiments of the present invention are processes for purifying a gas stream, comprising the steps of contacting a gas stream containing at least one toxic industrial compound (TIC) with a modified metal-organic frame (MOF) composition under purification conditions, thereby removing at least a portion of the at least one TIC from the gas stream, wherein the modified MOF comprises a corner metal unit comprising a metal (M) selected from Zr, V, Al, Fe, Cr, Ti, Hf, Cu, Zn, Ni, Hf, In, Ce, and mixtures thereof, and a linker molecule that links a metal ion atom of a different corner metal unit, and an inorganic metal (M') salt impregnated in the MOF, wherein the linker molecule comprises at least one organic ligand containing an arylamino group, or an arylamino group. The modified MOF composition is selected from a combination of at least one organic ligand containing an arylamino group and at least one organic ligand not containing an arylamino group, and the metal (M') is selected from Li, Na, K, Mg, Ca, Sr, Ba, Mn, Sc, Y, Ti, Zr, Hf, V, Cr, Mo, W, Fe, Co, Ni, Cu, Ag, Zn, Cd, Al, Ga, In, Sn, Pb and mixtures thereof, and the modified MOF composition has a minimum static ammonia capacity of at least 4 mmol / g, or at least 5 mmol / g, or at least 6 mmol / g, or at least 8 mmol / g, or at least 10 mmol / g, or at least 15 mmol / g, or at least 20 mmol / g, as measured at 10 Torr and 25°C. Typically, the static ammonia adsorption capacity is in the range of about 4 to about 25 mmol / g, as measured at 10 Torr and 25°C.

[0018] Further embodiments include cases where the gas flow is an air flow and at least one TIC is selected from ammonia, bromine, boron tribromide, bromine chloride, boron trichloride, bromine trifluoride, bromine pentafluoride, carbonyl fluoride, chlorine, chlorine pentafluoride, chlorine trifluoride, chlorosulfonic acid, dichlorosilane, ethylphosphone dichloride, fluorine, formaldehyde, hydrogen bromide, hydrogen chloride, hydrogen cyanide, hydrogen fluoride, hydrogen iodide, nitric acid, nitrogen dioxide, nitrogen tetroxide, nitrogen trioxide, phosgene, phosphorus trichloride, silicon tetrafluoride, sulfuric acid, sulyl chloride, titanium tetrachloride, tungsten hexafluoride, and mixtures thereof.

[0019] In certain embodiments, at least one TIC is a basic TIC such as ammonia. In other embodiments, at least one TIC is an acidic TIC such as nitrogen dioxide or chlorine.

[0020] In another specific embodiment, the modified MOF is formed into shapes selected from pellets, granules, spheres, discs, monoliths, amorphous particles, extruded products, and mixtures thereof. A binder may or may not be used when creating these shapes.

[0021] In yet another embodiment, the modified MOF is deposited onto a solid support selected from monoliths, spherical supports, ceramic foams, glass fibers, woven fabrics, nonwoven fabrics, membranes, pellets, extrudes, amorphous particles, and mixtures thereof.

[0022] A specific embodiment is when the solid support is a woven or nonwoven fabric, and / or when the solid support or nonwoven fabric is part of a facial mask.

[0023] Another embodiment of the present invention is an apparatus comprising at least one impregnated MOF composition as disclosed herein. In one embodiment, the apparatus further comprises an adsorbent other than the impregnated MOF composition as disclosed herein. In one embodiment, the other adsorbent is an unimpregnated MOF composition. In one embodiment, the other adsorbent is a zeolite. In one embodiment, the other adsorbent is activated carbon. In one embodiment, the apparatus comprises a mixture of at least one impregnated MOF composition as disclosed herein and another adsorbent. In one embodiment, the apparatus is an assembly comprising a layer comprising at least one impregnated MOF composition as disclosed herein and at least one layer comprising another adsorbent. In one embodiment, the apparatus comprises an assembly of at least two active layers comprising a first layer comprising activated carbon and a second layer comprising a modified MOF composition. In each such apparatus, the modified metal-organic framework (MOF) composition comprises a MOF comprising corner metal units comprising metal ion atoms selected from metals (M) Zr, V, Al, Fe, Cr, Ti, Hf, Cu, Zn, Ni, In, Ce, and mixtures thereof, and linker molecules linking the metal ion atoms of different corner metal units, and an inorganic metal (M') salt impregnated in the MOF, wherein the linker molecules are selected from at least one organic ligand comprising an arylamino group, or a combination of at least one organic ligand comprising an arylamino group and at least one organic ligand not comprising an arylamino group, and the metal (M') is selected from Li, Na, K, Mg, Ca, Sr, Ba, Mn, Sc, Y, Ti, Zr, Hf, V, Cr, Mo, W, Fe, Co, Ni, Cu, Ag, Zn, Cd, Al, Ga, In, Sn, Pb, and mixtures thereof, The modified MOF composition has a minimum static ammonia capacity of at least 4 mmol / g measured at 10 Torr and 25 °C and substantially retains its capacity for acidic TIC compared to the capacity of the MOF composition before metal (M') salt impregnation.

[0024] These and other aspects of the present invention will become apparent after a detailed description of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] As used throughout this specification and the claims, "substantially" means at least 70%, at least 80%, at least 90% or at least 95%.

[0026] As described above, the present invention relates to a modified metal-organic framework (MOF) composition, a process using the composition, a method for producing the composition, and an apparatus comprising the composition. The modified MOF of the present invention comprises a MOF and a metal (M') salt impregnated in the MOF. Impregnated in the MOF means impregnated in the surface or pores of the MOF.

[0027] A MOF is a coordination compound of metal ions and at least bidentate organic ligands, and is composed of corner metal units including metal ion atoms and linkers or ligands which are molecules forming a structure having a high surface area and pores of uniform size or pores of predetermined different sizes. Metals (M) that can be used for preparing the MOF of the present invention include, but are not limited to, Zr, V, Al, Fe, Cr, Ti, Hf, Cu, Zn, Ni, Hf, In, Ce, and combinations thereof. Preferred sets or subsets of the above metals include, but are not limited to, Zr, Al, Fe, Cu, or Zn, and combinations thereof.

[0028] The organic ligand that reacts with the metal ion can be selected from at least one organic ligand containing an arylamino group, or a combination of at least one organic ligand containing an arylamino group and at least one organic ligand not containing an amino group. Examples of organic ligands containing an arylamino group include, but are not limited to, 2-aminobenzene-1,4-dicarboxylic acid (NH2-BDC), 5-aminoisophthalic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, and mixtures thereof. Examples of organic ligands not containing an arylamino group include, but are not limited to, terephthalic acid (BDC), isophthalic acid, benzoic acid, trimesic acid, acrylic acid, and mixtures thereof. When the ligand is a combination of at least one organic ligand containing an arylamino group and at least one organic ligand not containing an amino group, the molar ratio of amino-containing to non-amino-containing ligands can be varied to 1:99 to 99:1, 10:90 to 90:10, 20:80 to 80:20, 30:70 to 70:30, 40:60 to 60:40, or 50:50. Furthermore, the ability to add amino functionality to MOFs by post-synthesis methods is also within the scope of this invention. Amino functionality can be added by post-synthesis addition of organic ligands or by addition of corner metal units. Typically, the addition of amino groups with organic linkers involves covalent bonding reactions, while addition with corner metal units uses chelate species that bond to open metal sites or substitute for structural components that are not major structural features.

[0029] Specifically, arylamino ligands can be added by suspending the MOF in a solvent after synthesis and replacing ligands without arylamino groups with ligands containing arylamino groups. The solvent can then be removed, and any excess ligands can be washed with a fresh solvent. This washing process is repeated until all excess ligands are removed. Examples of organic ligands containing arylamino groups include, but are not limited to, 2-aminobenzene-1,4-dicarboxylic acid (NH2-BDC), 5-aminoisophthalic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, and mixtures thereof. Ligand exchange after synthesis can provide a combination of at least one organic ligand containing an arylamino group and at least one organic ligand not containing an amino group, and the molar ratio of amino-containing to non-amino-containing ligands can vary to 1:99 to 99:1, 10:90 to 90:10, 20:80 to 80:20, 30:70 to 70:30, 40:60 to 60:40, or 50:50.

[0030] Another aspect of the composition of the present invention is an inorganic metal (M') salt impregnated into a MOF. M' metals that can be used to prepare the composition of the present invention include, but are not limited to, Li, Na, K, Mg, Ca, Sr, Ba, Mn, Sc, Y, Ti, Zr, Hf, V, Cr, Mo, W, Fe, Co, Ni, Cu, Ag, Zn, Cd, Al, Ga, In, Sn, Pb, and mixtures thereof. The M' metal exists as a metal salt and is impregnated into the surface of the MOF or into the pores of the MOF. It should be noted that M and M' metals may be the same or different. Preferably, the M' metal is different from the M metal. The amount of metal salt impregnated into the MOF can vary considerably, but is typically about 1% to 70% by weight as metal, or about 5% to 65% by weight, or about 10% to 60% by weight, or about 15% to 55% by weight, or about 20% to 50% by weight, or about 25% to 45% by weight. The inorganic M' salt is an anhydrous or hydrated salt selected from halides, sulfates, carbonates, nitrates, or mixtures thereof. In one embodiment, the M' salt is a hydrated or anhydrous halide salt.

[0031] The metal-impregnated MOF of the present invention is characterized by having the following properties. One property is that the static ammonia capacity measured at 10 Torr and 25°C is at least 4 mmol / g, or at least 5 mmol / g, or at least 6 mmol / g, or at least 8 mmol / g, or at least 10 mmol / g, or at least 15 mmol / g, or at least 20 mmol / g. Furthermore, the metal-impregnated MOF is characterized by substantially retaining its ability to adsorb acidic TICs compared to an unimpregnated MOF. In particular, it retains about 80% of its adsorption capacity for at least one acidic TIC. One of the general properties of the MOF is at least 1,000, or at least 1,100, or at least 1,200, or at least 1,300, or at least 1,400 m 2 This is the Brunauer-Emmett Teller (BET) surface area per gram. The metal-impregnated MOF of the present invention is characterized by retaining at least 50% of the BET surface area (SA) of the unimpregnated MOF.

[0032] Another aspect of the present invention is a process for preparing metal-impregnated MOFs. The first step in this synthesis is to prepare the MOF by a synthesis known in the literature. Typically, a solution of the desired metal (M) and ligand is prepared. The metal (M) is introduced as a metal salt. The salt can be a nitrate, halide, sulfate, carbonate, oxyhalide, oxynitrate, oxysulfate, oxycarbonate, etc. Specific examples of usable salts include, but are not limited to, zirconium chloride, zirconium bromide, zirconium oxynitrate, zirconium oxychloride, vanadium chloride, copper sulfate, iron chloride, zinc nitrate, or zinc carbonate, and mixtures thereof.

[0033] As described above, the ligand used may be at least one organic ligand containing an arylamino group, or a mixture of an organic ligand containing at least one arylamino group and an organic ligand not containing an arylamino group. Examples of organic ligands containing an amino group include, but are not limited to, 2-aminobenzene-1,4-dicarboxylic acid (NH2-BDC), 5-aminoisophthalic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, and mixtures thereof. Examples of organic ligands not containing an amino group include, but are not limited to, terephthalic acid (BDC), isophthalic acid, benzoic acid, trimesic acid, acrylic acid, and mixtures thereof. When a mixture of amino and non-amino ligands is used in synthesis, they are added in molar ratios to achieve the desired molar ratio in the MOF, as described above. The molar ratio of the metal salt to the ligand is also adjusted to achieve a specific molar ratio in the MOF.

[0034] A metal compound, which is the source of metal M, and one or more ligands are mixed in a solvent or a mixture of solvents. Examples of usable solvents include, but are not limited to, amides, alcohols, water, and mixtures thereof. Specific solvents include dimethylformamide, water, ethanol, isopropanol, and mixtures thereof.

[0035] Optionally, an acid may be present in the reaction mixture during MOF synthesis. In one embodiment, the acid present during MOF synthesis includes a monocarboxylic acid. In one embodiment, the monocarboxylic acid can be selected from formic acid, acetic acid, benzoic acid, dichloroacetic acid, trifluoroacetic acid, and mixtures thereof. In one embodiment, the acid present during MOF synthesis further includes an inorganic acid such as hydrochloric acid, nitric acid, or sulfuric acid, or a mixture thereof. In one embodiment, the acid present during MOF synthesis includes a mixture of a monocarboxylic acid and an inorganic acid.

[0036] Once the reaction mixture is formed, i.e., all its components are solubilized, the reaction mixture is reacted at a temperature and time that forms the desired MOF. The reaction temperature can be varied between about 50°C and about 200°C, or between about 75°C and about 125°C. The reaction mixture is reacted at the desired temperature for a time selected from about 1 hour to about 78 hours, or about 8 hours to about 48 hours, or about 12 hours to about 24 hours. Once the MOF powder is formed, it is isolated by means of filtration, centrifugation, etc. In some embodiments, the isolated MOF can be washed with an acid composition containing an inorganic acid. Optionally, the acid washing may be a mixture of one or more inorganic acids and one or more organic acids. Preferred inorganic acids include hydrochloric acid, nitric acid, and sulfuric acid. Preferred organic acids include formic acid. The wet MOF is dried at a temperature of about 40°C to about 250°C, or at a temperature of about 75°C to about 150°C. The drying time for a wet MOF can vary considerably, but is typically between approximately 2 hours and 14 days, or between approximately 8 hours and 7 days, or between approximately 2 days and 7 days.

[0037] Next, the MOF is brought into contact with a solution of a metal salt that is the source of metal M', thereby impregnating the MOF with the metal (M') salt. The metal M' can be selected from one or more of the following: Li, Na, K, Mg, Ca, Sr, Ba, Mn, Sc, Y, Ti, Zr, Hf, V, Cr, Mo, W, Fe, Co, Ni, Cu, Ag, Zn, Cd, Al, Ga, In, Sn, Pb, and mixtures thereof. The salt may be an inorganic salt selected from one or more of the following: metal nitrates, halides, sulfates, carbonates, etc., with halides being a specific example. The salt may be in the form of a hydrate or anhydrous. Specific examples include, but are not limited to, magnesium chloride, nickel chloride, manganese chloride, zinc chloride, nickel nitrate, magnesium nitrate, nickel sulfate, and nickel carbonate. In one embodiment, the metal salt is NiCl26H2O. In one embodiment, the metal salt is MgCl2 (anhydrous). In one embodiment, the metal salt is MnCl24H2O. In another embodiment, the metal salt is ZnCl2 (anhydrous). In yet another embodiment, the metal salt is the hydrated form of ZnCl2. The metal salt is dissolved in a solvent such as alcohol, water, acetone, and ether. This solution is contacted with the MOF at a temperature from room temperature to about 65°C for a period of about 1 minute to about 24 hours. The metal-impregnated MOF is then isolated by filtration, centrifugation, etc., and dried at a temperature from about 60°C to about 200°C.

[0038] Metal-impregnated MOFs can be formed into various shapes, as described later. When a step of forming a molded body from MOF powder is used, the impregnation step can be performed before, during, or after the binder incorporation step and the molded body formation step.

[0039] In one embodiment, a particular process involves preparing impregnated MOF granules as follows: mixing the dried MOF powder with a binder and thoroughly mixing the combination. Both organic and inorganic binders can be used. Specific examples of inorganic binders include, but are not limited to, clays such as kaolin, attapulgite, and boehmite, alumina, silica, metal oxides, and mixtures thereof. Specific examples of organic binders include, but are not limited to, polymers such as polyvinylpyrrolidone (PVP), starch, gelatin, cellulose, cellulose derivatives, sucrose, polyethylene glycol, and mixtures thereof.

[0040] In one embodiment, the MOF and binder are first thoroughly mixed, and then a solution containing the desired metal (M') salt is mixed into the MOF / binder mixture. This impregnated MOF is mixed for a period of time from about 1 minute to about 24 hours until granules of the desired size are obtained. It is understood that a range of sizes is always obtained, and therefore the granules need to be sizing, i.e., sieved, to separate granules having the desired size or size range. The size range of the granules will depend on the specific application of the modified MOF and on various parameters such as pressure drop and packing density. Granules with an average diameter of about 1190 microns (16 mesh) to about 841 microns (20 mesh), or about 841 microns (20 mesh) to about 400 microns (40 mesh), or about 595 microns (30 mesh) to about 297 microns (50 mesh) are desired. Average diameter means the average diameter assuming an approximate sphere. This does not mean that the granules are actually spherical, but rather that the granules pass through a mesh sieve of a given diameter. Once granules of the desired size are obtained, the modified MOF is activated by drying them under vacuum at a temperature of about 50°C to about 250°C for the time required to reach a pressure of about 0.1 torr. Other means of incorporating a binder into the MOF composition to form granules or other shapes will be understood by those skilled in the art.

[0041] As described, the metal-impregnated MOF compositions of the present invention are used to remove both basic and acidic contaminants, such as TICs, from gas streams. Gas streams that may need to be purified include, but are not limited to, air streams, industrial gas streams, off-gassing streams, or contaminated gas streams. The modified MOFs of the present invention are particularly suitable for removing acidic and basic contaminants from air streams. Contaminants or toxic industrial chemicals that can be removed by the MOFs of the present invention include, but are not limited to, ammonia, bromine, boron tribromide, bromine chloride, boron trichloride, bromine trifluoride, bromine pentafluoride, carbonyl fluoride, chlorine, chlorine pentafluoride, chlorine trifluoride, chlorosulfonic acid, and dichlorosilane. This includes, but is not limited to, ethylphosphonic acid dichloride, fluorine, formaldehyde, hydrogen bromide, hydrogen chloride, hydrogen cyanide, hydrogen fluoride, hydrogen iodide, nitric acid, nitrogen dioxide, nitrogen tetroxide, nitrogen trioxide, phosgene, phosphorus trichloride, silicon tetrafluoride, sulfuric acid, sulyl chloride, titanium tetrachloride, tungsten hexafluoride, and mixtures thereof.

[0042] The amount of contaminants (acidic or basic) that a modified MOF can remove is at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, or at least 99% of the contaminants. In one embodiment, the gas flow is an airflow, the contaminants are NO2 and / or ammonia, and the modified MOF removes at least 80% of the NO2 or at least 80% of the ammonia in the airflow. In another embodiment, a container having inlet and outlet ports is filled with modified MOF material through which a gas flow is passed, thereby substantially removing at least one basic contaminant and at least one acidic contaminant. To achieve the desired removal amount, the gas flow is passed through the MOF at a rate of about 10 L / min to about 500 L / min, or about 30 L / min to about 200 L / min, or about 50 L / min to about 120 L / min.

[0043] The modified MOF composition of the present invention can be used in powder form, but it may be advantageous to form the MOF composition into various shapes such as pellets, spheres, discs, monoliths, amorphous particles, and extruded bodies. Methods for forming these types of shapes are well known in the art. Specific methods for forming granular bodies are described above. The modified MOF material can be formed into various shapes by itself or by including a binder. When selecting a binder, it is important to select one that does not adversely affect the surface area and adsorption capacity after the desired molded body is formed. Materials that can be used as binders include, but are not limited to, cellulose, silica, carbon, alumina, and mixtures thereof. Forming of the MOF composition into a molded body can be done before, during, or after impregnation of the MOF.

[0044] The molding process typically involves mixing the modified MOF composition with a solvent or a binder + solvent to prepare a thick paste-like material. Once the paste-like material is formed, it can be extruded through a die with a hole of approximately 1-4 mm to form extrudes of various lengths, for example, 2-50 mm. The paste, or the powder itself, can be pressurized under high pressure to form pellets or tablets. Other means of forming the shape include pressure molding, metal forming, pelletizing, granulation, extrusion, rolling, and marmarizing.

[0045] In yet another aspect of the present invention, the metal-impregnated MOF material can be deposited on articles such as monoliths, spherical supports, ceramic foams, glass fibers, woven fabrics, nonwoven fabrics, membranes, pellets, extrudes, amorphous particles, and mixtures thereof. If the desired article is a monolith, spherical support, ceramic foam, pellets, extrudes, or amorphous particles, a slurry of the MOF composition can be prepared and deposited on the article by means of dipping, spray drying, etc., followed by drying and optionally firing. In the case of membranes, it is possible to form the modified MOF composition directly on the membrane. The metal-impregnated MOF compositions of the present invention can be deposited or dispersed on fabrics (woven and nonwoven fabrics) or polymers by techniques such as electrospinning, direct crystal growth, and layered deposition.

[0046] The metal-impregnated MOF-containing articles described in the previous paragraph can be used as is to purify air or other gaseous streams containing contaminants. The air or other gaseous stream can flow through the article, e.g., monoliths, foams, membranes, or cloths, through which the metal-impregnated MOF adsorbs at least a portion of at least one contaminant. The metal-impregnated MOF articles can also be placed in various types of rigid containers. For example, extruded materials, tablets, or spheres can be housed in beds through which air or other gaseous streams flow. The beds can be placed in various types of housings, such as filter canisters with inlets and outlets. Cloths (both woven and nonwoven) can also be formed into filters, such as pleated filters. These filters can also be housed in rigid containers, such as cartridges, through which the flow to be treated flows. In certain embodiments, the cartridge is part of a face mask. Pleated filters can also be supported by frames of various shapes and sizes through which gaseous streams can flow. The frames can be made from various types of materials, such as metal, wood, and plastic, but are not limited to these. Glass fibers can be molded into glass wool and housed in a rigid filter frame.

[0047] Metal-impregnated MOFs can be used in apparatus comprising at least one impregnated MOF composition as disclosed herein. In one embodiment, the apparatus further comprises an adsorbent other than the impregnated MOF composition as disclosed herein. In one embodiment, the other adsorbent is a non-metal-impregnated MOF composition. In one embodiment, the other adsorbent is a zeolite. In one embodiment, the other adsorbent is activated carbon. In one embodiment, the apparatus comprises a mixture of at least one impregnated MOF composition as disclosed herein and the other adsorbent. In one embodiment, the apparatus comprises a layer comprising at least one impregnated MOF composition as disclosed herein and at least one layer comprising another adsorbent. In one embodiment, the apparatus comprises an assembly or apparatus comprising a non-layered mixture of multiple layers or particles through which a gas flow, e.g., an air flow, is passed. In a particular embodiment, the first layer in contact with the gas flow is a metal-impregnated MOF layer, and the second layer comprises another adsorbent such as activated carbon, zeolite, or other known adsorbents. In another embodiment, the gas flow may first come into contact with a layer containing another adsorbent, and then with a layer containing a modified MOF. Additional layers may be added as needed, such as a hopkalite layer. For example, layers of two different metal-impregnated MOFs may be used, or layers of metal-impregnated MOFs and unimpregnated MOFs may be used. Alternatively, two or more modified MOFs may be mixed to form a single layer, or the layer may consist of metal-impregnated MOFs and unimpregnated MOFs. These layers may be placed in beds that can be housed in rigid structures such as canisters, or in larger containers such as airflow entering commercial buildings when large gas flows are being purified. As described above, the metal-impregnated MOFs in the layers may be in powder form or in any of the shapes and forms described above.

[0048] Activated carbon, which can be used as an adsorbent as described above, is a highly porous, high-surface-area adsorbent material that mostly has an amorphous structure. It is mainly composed of carbon atoms in an aromatic arrangement bonded together by random crosslinks. Its degree of order varies depending on the starting material and thermal history. Graphite plates from steam-activated coal are somewhat ordered, but chemically activated wood exhibits a more amorphous aromatic structure. The random bonding creates a highly porous structure with numerous cracks, gaps, and voids between the carbon layers. Activated carbon can be produced in the form of powder (PAC), granules (GAC), or extruded products (EAC). All three forms are available in various particle sizes.

[0049] By depositing modified MOFs and adsorbents such as activated carbon onto a fabric (woven or nonwoven), the fabric can be arranged as a layer in a face mask.

[0050] A pleated sheet can be formed containing layers of activated carbon or other adsorbents and metal-impregnated MOF. The pleated sheet can be formed into various configurations such as filter canisters, or housed in rigid containers such as frames made from various materials such as plastic, wood, metal, or cardboard. Examples Example 1: Synthesis of metal-impregnated Zr(NH2-BDC)

[0051] Zr(BDC-NH2), also known as UiO-66-NH2, was prepared using a procedure described in the literature. Generally, this procedure involved dissolving the NH2-BDC ligand in a solvent such as DMF (dimethylformamide), then adding formic acid, and subsequently heating the solution to a temperature of about 90°C, adding ZrO(NH3), and allowing it to react for a period of time to provide the MOF. The MOF powder was isolated, washed with DMF and acetone, washed with hydrochloric acid, and dried at a temperature of about 100°C for about 12 hours.

[0052] Add 200 mg of the Zr(NH2-BDC)MOF synthesized above to a 30 mL vial. To this powder, add 0.936 mmol of either NiCl26H2O, MgCl2 (anhydrous), MnCl24H2O, or ZnCl2 (anhydrous). Then, add 10 mL of methanol to the NiCl26H2O and MgCl2 (anhydrous) samples, or acetone to the ZnCl2 (anhydrous) sample. Sonicate the vial containing the mixture for 1 minute, and then evaporate most of the methanol or acetone. The resulting solid was dried overnight at 100°C. Example 2: Synthesis of MgCl2-modified Zr(NH2-BDC) using a binder

[0053] Zr(NH2-BDC) was prepared according to the procedure of Example 1, except that the MOF was dried at 80°C to achieve a hydration level of 10-15%. 1948 g of Zr(BDC-NH2) was added to a pan mixer along with 3 wt% PVP, and the mixture was thoroughly mixed. A mixture of diluted MgCl2 solution was prepared using 328 mL of saturated MgCl2 solution diluted to the approximate pore volume of the MOF. This was added to the mixture. This new mixture was continued to mix until granules were formed. These granules were sieved, and granules of the desired size were dried under vacuum at 100°C until a dynamic pressure (<0.1 Torr) was reached. Example 3: Synthesis of ZnCl2-modified Zr(NH2-BDC) using a binder

[0054] Zr(NH2-BDC) was prepared according to the procedure of Example 1. This material was mixed with a colloidal silica solution in a pan mixer to obtain a compressible mixture. This material was roll-compressed and ground to the desired size. This material was then immersed for approximately 20 hours in a ZnCl2 / acetone solution of a concentration selected to provide the desired zinc load to the final MOF product. After immersion, the material was air-dried and re-coated with the same colloidal silica solution. This material was air-dried and then dried under vacuum at 100°C until a dynamic pressure (<0.1 Torr) was reached.

[0055] In the following examples, all ammonia adsorption and desorption measurements were performed at 25°C using a Micromeritics 3Flex Surface Characterization Analyzer (Micromeritics, Norcross GA), employing absolute pressure administration and a 3-second equilibration interval.

[0056] In the following examples, unless otherwise specified, all N2 gas adsorption and desorption measurements were performed at 77K using a Micromeritics Tristar II 3020 system (Micromeritics, Norcross, GA). Samples ranging from 75–200 mg were used for each measurement. Specific surface area for N2 was calculated using the Brunauer-Emmet Teller (BET) model, within the range of 0.005 < P / Po < 0.05. N2 absorption was measured at P / Po = 0.9, where P / Po is the measurement pressure relative to atmospheric pressure.

[0057] Example 4: Absorption Test Table 1. Impregnation amount of Zr(NH2-BDC) metal and NH3 absorption amount (mmol / g at 25℃, 10 Torr) [Table 1]

[0058] It was found that using various metal salts to impregnate Zr(NH2-BDC)MOFs could increase the ammonia adsorption capacity of the metal-impregnated MOFs. Furthermore, it was shown that increasing the amount of metal salt impregnating the MOF increased the amount of ammonia adsorbed. However, as expected, the surface area decreased as the metal salt load increased.

[0059] Cl2 absorption was measured as follows: Cl2 gas was injected into the mixed ballast, and then 10,000 mg / m³ was added. 3 It was pressurized to achieve the concentration. Next, the ballast contents were mixed with a diluted air stream under dry conditions to achieve a challenge concentration of 2,000 mg / m³. 3This was achieved. This mixed airflow passed through an adsorbent bed immersed in a water bath with a temperature control of 20°C. Approximately 50 mm of each sample. 3 The gas was packed into a 4mm inner diameter tube, which corresponds to a bed depth of 4mm and a residence time of approximately 0.15 seconds. The outflow stream was then passed through a continuously operating Hewlett-Packard 5890 Series II gas chromatograph equipped with an 11.7 eV lamp photoionization detector. The load was calculated by integrating the breakthrough curve at saturation. Table 2. Impregnation of Zr(NH2-BDC) metal and Cl2 absorption at 25°C and 10 torr. [Table 2]

[0060] Table 2 shows that Zr(NH2-BDC) impregnated with nickel chloride or magnesium chloride retains the chlorine (acidic TIC) adsorption capacity of unimpregnated MOFs. This is an unexpected result, as the ammonia adsorption capacity increased with the same metal-impregnated MOFs (see Table 1). The ability of MOFs to adsorb substantial amounts of both basic and acidic TIC has never been observed before. Example 5: Breakthrough Test

[0061] A fixed amount of Zr(NH2-BDC) (0.25 g) was packed into the breakthrough system. The first sample was unimpregnated with metal, while the other samples were impregnated with the metals listed in Table 3. After nitrogen purging, a stream containing 250 ppm ammonia in He gas was introduced and flowed through the MOF at 50 standard cubic centimeters / second (sccms) at 25°C. The breakthrough time was recorded when the outlet concentration reached 100 ppm. Table 3: Effect of metal impregnation on NH3 breakthrough of Zr(NH2-BDC) [Table 3]

[0062] The results in Table 3 show that impregnation of Zr(NH2-BDC)MOF with a metal salt (MgCl2) increased the breakthrough time by up to 93%. The breakthrough was dependent on the concentration of the metal salt, with the greatest breakthrough occurring at an 8 wt% magnesium load.

[0063] While the foregoing refers to specific embodiments, it will be understood that the present invention is not so limited. Those skilled in the art will realize that various modifications can be made to the disclosed embodiments, and such modifications are intended to fall within the scope of the present invention. The present invention includes the following embodiments. [1] A MOF comprising a corner metal unit in which metal (M) is selected from Zr, Al, Fe, Cu, Zn, and mixtures thereof and a linker molecule that links the metal ion corner atom, and an inorganic metal (M') salt impregnated in the MOF, The linker molecule is selected from at least one organic ligand containing an arylamino group, or a combination of at least one organic ligand containing an arylamino group and at least one organic ligand not containing an arylamino group. Organic ligands containing an arylamino group include 2-aminobenzene-l,4-dicarboxylic acid (NH₃). 2 Selected from -BDC), 5-aminoisophthalic acid, 3-aminobenzoic acid, 4-aminobenzoic acid and mixtures thereof, Organic ligands that do not contain arylamino groups are selected from terephthalic acid (BDC), isophthalic acid, benzoic acid, trimesic acid, acrylic acid, and mixtures thereof. The aforementioned metal (M') is selected from Cu, Zn, Ni, Mn, Mg, Ca, and mixtures thereof. The static ammonia volume measured at 25°C and 10 Torr was at least 4 mmol / g, and substantially retained its capacity for acidic TIC. The metal (M') salt is characterized by being selected from anhydrous or hydrated halides, sulfates, carbonates, nitrates, or mixtures thereof. Metal-impregnated metal-organic framework (MOF) compositions. [2] The metal-impregnated metal-organic frame (MOF) composition according to [1], characterized in that the metal (M') is present in an amount of 1% to 70% by weight as a metal. [3] A metal-impregnated metal-organic structure (MOF) composition according to [1] or [2], characterized by comprising a binder selected from an organic binder, an inorganic binder, or a mixture thereof. [4] A metal-impregnated metal-organic structure (MOF) composition according to any one of [1] to [3], characterized by being formed into shapes selected from pellets, granules, spheres, discs, monoliths, amorphous particles, extruded products, and mixtures thereof. [5] A method for purifying a gas stream, comprising contacting a gas stream containing at least one toxic industrial compound (TIC) with a metal-impregnated metal-organic structure (MOF) composition according to any one of [1] to [4] under purification conditions, thereby removing at least a portion of the at least one toxic industrial compound from the gas stream. A device for purifying a gas flow, comprising a metal-impregnated metal-organic structure (MOF) composition as described in any of [6][1] to [4], An apparatus characterized in that a metal-impregnated metal-organic structure (MOF) composition is deposited onto a solid support selected from monoliths, spherical supports, ceramic foams, glass fibers, woven fabrics, nonwoven fabrics, membranes, pellets, extrudes, amorphous particles, and mixtures thereof. [7] The apparatus according to [6], characterized in that the solid support is a woven or nonwoven fabric.

Claims

1. The MOF comprises a corner metal unit in which metal (M) is selected from Zr, Al, Fe, Cu, Zn, and mixtures thereof, and a linker molecule that connects the metal ion corner atom, and an inorganic metal (M') salt impregnated in the MOF. The static ammonia volume measured at 25°C and 10 Torr was at least 4 mmol / g, and substantially retained the volume for acidic TIC. The linker molecule is selected from at least one organic ligand containing an arylamino group, or a combination of at least one organic ligand containing an arylamino group and at least one organic ligand not containing an arylamino group. Organic ligands containing an arylamino group include 2-aminobenzene-l,4-dicarboxylic acid (NH ２ Selected from -BDC), 5-aminoisophthalic acid, 3-aminobenzoic acid, 4-aminobenzoic acid and mixtures thereof, Organic ligands that do not contain arylamino groups are selected from terephthalic acid (BDC), isophthalic acid, benzoic acid, trimesic acid, acrylic acid, and mixtures thereof. The metal (M') is selected from Cu, Zn, Ni, Mn, Mg, Ca, and mixtures thereof. The metal (M') salt is characterized by being selected from anhydrous or hydrated halides, sulfates, carbonates, nitrates, or mixtures thereof. Metal-impregnated metal-organic framework (MOF) compositions.

2. The metal-impregnated metal-organic structure (MOF) composition according to claim 1, characterized in that the metal (M') is present in an amount of 1% to 70% by weight as a metal.

3. The metal-impregnated metal-organic structure (MOF) composition according to claim 1 or 2, characterized by comprising a binder selected from an organic binder, an inorganic binder, or a mixture thereof.

4. A metal-impregnated metal-organic structure (MOF) composition according to any one of claims 1 to 3, characterized in that it has a shape selected from pellets, granules, spheres, discs, monoliths, amorphous particles, extruded products, and mixtures thereof.

5. A method for purifying a gas stream, comprising contacting a gas stream containing at least one toxic industrial compound (TIC) with a metal-impregnated metal-organic structure (MOF) composition according to any one of claims 1 to 4 under purification conditions, thereby removing at least a portion of the at least one toxic industrial compound from the gas stream.

6. An apparatus for purifying a gas stream containing a metal-impregnated metal-organic structure (MOF) composition according to any one of claims 1 to 4, and containing at least one toxic industrial compound (TIC), The apparatus is characterized in that a metal-impregnated metal-organic structure (MOF) composition is deposited on a solid support selected from monoliths, spherical supports, ceramic foams, glass fibers, woven fabrics, nonwoven fabrics, membranes, pellets, extrudes, amorphous particles, and mixtures thereof.

7. The apparatus according to claim 6, characterized in that the solid support is a woven fabric or a nonwoven fabric.

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