Modified weak-base anion exchange resin sorbents for direct air capture of carbon dioxide

Abstract

The invention relates to new carbon dioxide adsorbents based on modified weak base anion exchange resins (WBAERs) comprising a crosslinked polymeric backbone containing appended primary and / or secondary amines. The WBAERS materials are insoluble in water and common organic solvents, have surface areas of 5-50 m2 / g, and can be in either bead or powder form. The WBAER materials are suspended in water or a polar organic solvent and treated with haloalcohol or halohydrin compounds to effect the modification. The modified materials exhibit significantly improved oxidative stability compared with the unmodified ion-exchange resins without much impact on their CO2 uptake capacity or CO2 uptake kinetics. The modified materials remain insoluble in water and common organic solvents and, therefore, are not susceptible to leaching under steam-based or moisture-based sorbent regeneration conditions.

Description

MODIFIED WEAK-BASE ANION EXCHANGE RESIN SORBENTS FOR DIRECT AIR CAPTURE OF CARBON DIOXIDECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 63 / 558,793, filed on February 28, 2024, and to U.S. Provisional Application No. 63 / 641,936, filed on May 2, 2024; the disclosures of which are each incorporated herein by reference.TECHNICAL FIELD

[0002] The invention relates to inexpensive and durable sorbent materials and methods useful for direct capture and separation of carbon dioxide from point sources or directly from the atmosphere. In particular, chemical modification of insoluble, porous weak-base ion exchange resin sorbents with haloalcohols or halohydrins yields modified sorbents with improved stability and improved durability and capture performance stability under direct air capture (DAC) process conditions.BACKGROUND

[0003] Global warming is posing devastating effects on our climate, health, and communities.Coastal flooding due to rising sea levels, extended wildfire seasons, as well as more destructive hurricanes are the direct impacts of climate change. Moreover, global food and water security are at stake. There is a consensus among scientists that global warming is directly linked to the increase in the level of greenhouse gases in the atmosphere. Carbon dioxide (CO2) is a major greenhouse gas, and its concentration in the atmosphere has sharply increased over the past century due to the burning of fossil fuels. Although efforts are underway to move toward renewable energy sources that do not emit greenhouse gases, shifting our energy supply to completely renewable sources is not possible in the near term and requires further technological advancements and significant global investments.Therefore, there is a growing need for technologies that can efficiently capture carbon dioxide from the flue gas of power plants and other industrial processes and, increasingly, even from ambient air. These processes are commonly referred to as carbon capture processes and carbon capture directly from ambient air is known as direct air capture (DAC).

[0004] Carbon capture processes commonly utilize some type of regenerable sorbent material to capture CO2from a source gas stream and then subsequently release the adsorbed CO2under controlled conditions so that it can be captured and stored. Large-scale gas-liquid processes utilizing causticsolutions or liquid amine materials to capture CO2from high-concentration point-sources such as flue gas have been developed but require high capital expenditures and long lead times to construct, have high energy requirements, and are much less efficient at the relatively low concentrations of CO2present in ambient air. Furthermore, liquid sorbent materials are commonly toxic, corrosive, and / or otherwise hazardous in use, so extreme and expensive precautions must be utilized. Therefore, DAC processes more commonly utilize some type of regenerable solid sorbent material to capture the CO2from a gas or air stream. Solid CO2sorbents include various zeolites or molecular sieves; amine- functionalized silicious, inorganic, activated carbon, graphitic, metal organic framework (MOF) or polymeric supports; amine-functionalized carbon, glass, cellulosic, or polymeric fibers; oligomeric and polymeric amines; and basic or weakly basic ion exchange resins. In some cases, the solid CO2sorbents are utilized in powder or pellet form in fluidized bed or packed bed configurations. In other cases, the solid CO2sorbents are utilized in fibrous webs, mats, or woven fabrics through which air is passed. In still other cases, the solid CO2sorbents are formed into structured monoliths or other structured forms such as sheets, films, membranes, or plates through or around which air may be passed.

[0005] A DAC process typically involves a first step of moving ambient air through a bed of a solid sorbent that is effective at selectively capturing a significant portion of the CO2included therein. Due to the low concentrations (currently a little over 400 parts per million) of CO2in ambient air, high volumes of ambient air need to be moved and processed in a DAC process. Once the sorbent reaches a level of significant saturation of CO2, it needs to be regenerated in a second step. During regeneration, the adsorbent bed is treated with, for example, heat (commonly referred to as thermal-swing), vacuum, moisture (commonly referred to as moisture-swing), steam, or some combination thereof to cause the CO2to desorb from the sorbent. One approach utilizes a combination of heat and vacuum to effect desorption and is commonly known as temperature-vacuum swing adsorption (TVSA). A particular version, known in the art as steam-assisted TVSA, utilizes heat from steam, flowing steam through the adsorbent bed to efficiently transfer heat to the adsorbent bed. Along with heating the adsorbent bed, the steam also acts as a purge medium to help carry the desorbed CO2out of the bed. The released CO2is subsequently captured, and the regenerated sorbent can then be returned to the first step and reused to capture more CO2. To be cost efficient, a sorbent material must be able to undergo many thousands of these cycles without significant degradation in performance.

[0006] Solid polyamine-based sorbent materials seem suited for CO2capture under DAC conditions, exhibiting relatively fast kinetics and good capacity. Representative polyamine sorbents include polymers such as polyethyleneimines (PEI) and polypropyleneimines (PPI) and oligomers such astetraethylenepentamine (TEPA), triethylenetetramine (TETA), pentaethylenehexamine (PEHA), and spermine. However, amine and polyamine materials are intrinsically susceptible to oxidation, especially at temperatures over about 50 to 60 °C. Considering that typical amine sorbent regeneration temperatures approach or even exceed 100°C, care must be taken to sufficiently cool the sorbent prior to reintroducing air to restart the adsorption cycle, thereby increasing overall cycle time. Furthermore, oligomeric polyamine materials exhibit considerable volatility at these elevated temperatures, and most polyamine materials exhibit considerable water solubility, making leaching a problem under steamregeneration conditions. In some cases, the amine groups are chemically appended to supports such as silica or alumina, although such materials are still susceptible to amine oxidation and hydrolysis over many cycles. Goeppert, et al. (ChemSusChem, 2019, 12, 1712-1723 and U.S. Patent No. 10,751,689) demonstrated that oligomeric polyamines such as TEPA and PEHA reacted with propylene oxide exhibited lower volatility and improved oxidative stability under thermal regeneration conditions while still showing excellent adsorption performance. Choi, et al. (Nature Communications, 2016, 7, 12640 and U.S. Patent No. 10,010,861) demonstrated that PEI reacted with butylene oxide similarly exhibited improved oxidative stability under thermal-swing conditions with excellent adsorption performance. However, such modified polyamines still exhibit high water solubility, making them unsuitable for use in systems utilizing moisture-swing or steam-regeneration.

[0007] Some solid-amine DAC sorbents comprise crosslinked polymeric backbones with appended amines, including certain classes of weak-base anion exchange resins (WBAERs). These materials have solid porous structures based on polymeric backbones crosslinked with divinylbenzene (DVB), such as poly(styrene-DVB), poly(vinylamine-DVB), poly(allylamine-DVB, poly(acrylate-DVB), or poly(methacrylate-DVB). These amino-based sorbent materials, especially ion-exchange resins with a backbone of polystyrene-divinylbenzene grafted with primary amines or secondary amines, are good material candidates for steam-assisted DAC processes as shown, for example, by Bos, et al., in Chemical Engineering Science: X, 2019, 2, 100020 and by Vargas, et al. in International Publication No. WO 2023 / 110520 for certain crosslinked poly(styrene-DVB) copolymers with amine functional groups and by Chintapalli, et al. in U.S. Patent No. 11,612, 852 for certain crosslinked poly(vinylamine-DVB) copolymers, the disclosures of which are each incorporated herein by reference. In these materials, the amine functional groups are chemically attached to the backbone of the insoluble cross-linked polymer substrate, preventing steam leaching. However, oxidative amine degradation is still problematic under DAC conditions since the feed stream is air with over 20% oxygen. Wang, et al. (International Publication No. WO 2024 / 056715) demonstrated that the oxidative stability of anion exchange resins based onaminated phenylic polymers could be enhanced by reaction with small epoxides, although it was important to keep the extent of reaction low to prevent the formation of large amounts of tertiary amines which are inactive for CO? capture. Therefore, it is highly important to develop materials that are resistant to oxidation, are stable and non-leachable under steam exposure, and that retain high CO? capture activity.SUMMARY

[0008] The invention relates to new carbon dioxide adsorbents based on modified weak base anion exchange resins (WBAERs) comprising a crosslinked poly(styrene-divinylbenzene) skeleton containing appended primary and / or secondary amines. The WBAER materials are insoluble in water and common organic solvents, have surface areas of 5 to 50 m2 / g, and can be in either bead or powder form. The WBAER materials are suspended in water or a polar organic solvent and treated with haloalcohol or halohydrin compounds to affect the functionalization. The modified materials exhibit significantly improved air stability of the ion-exchange resins without much impact on their CO? uptake capacity or CO? uptake kinetics. The modified materials remain insoluble in water and common organic solvents and, therefore, are not susceptible to leaching under steam-based or moisture-based sorbent regeneration conditions.

[0009] The invention further relates to a water insoluble modified weak-base anion exchange resin comprising a porous crosslinked polymeric backbone further comprising primary and / or secondary amine groups and wherein at least some of the amine hydrogen groups of the primary and / or secondary amine groups are further modified via a reaction with a haloalcohol or a halohydrin compound.

[0010] In some embodiments of the invention, the porous crosslinked polymeric backbone comprises divinylbenzene (DVB) as a crosslinking comonomer. In some embodiments of the invention, the porous crosslinked polymeric backbone is selected from the group consisting of a styrene-DVB copolymer, a vinylamine-DVB copolymer, an allylamine-DVB copolymer, an acrylate-DVB copolymer, and a methacrylate-DVB copolymer. In some embodiments of the invention, the porous crosslinked polymeric backbone comprises a styrene-DVB copolymer. In some embodiments of the invention, the insoluble weak-base anion exchange resins (WBAERs) comprise primary amine groups, and no or substantially no (e.g., < 1%, < 0.5%, or < 0.1%; based on the total amount of amine groups present) secondary amine groups, that can be treated with haloalcohol or halohydrin compounds to yield modified resins demonstrating good CO? adsorption / desorption performance along with improved oxidative stability. In some embodiments of the invention, the insoluble WBAERs comprise bothprimary and secondary amine groups that can be treated with haloalcohol or halohydrin compounds to yield modified resins demonstrating good CO2 adsorption / desorption performance along with improved oxidative stability. In some embodiments of the invention, the WBAERs may comprise 1 - 99%, based on the total amount of amine groups present (e.g., 5 - 95%, 10 - 90%, 20 - 80%, 30 - 70%, 40 - 60%, or 45 - 55%), of primary amine groups and 99 - 1%, based on the total amount of amine groups present (e.g., 95 - 5%, 90 - 10%, 80 - 20%, 70 - 30%, 60 - 40%, or 55 - 45%, based on the total amount of amine groups present), of secondary amine groups. In some embodiments of the invention, the insoluble WBAERs comprise secondary amine groups, and no or substantially no (e.g., < 1%, < 0.5%, or < 0.1%; based on the total amount of amine groups present) primary amine groups, that can be treated with haloalcohol or halohydrin compounds to yield modified resins demonstrating good CO2 adsorption / desorption performance along with improved oxidative stability. Modest levels of modification improved oxidative stability with little impact on CO2 uptake capacity or CO2 uptake kinetics. The modified materials remain insoluble in water and common organic solvents and, therefore, are not susceptible to leaching under steam-based or moisture-based sorbent regeneration conditions.

[0011] The invention further relates to reacting haloalcohol or halohydrin compounds with insoluble WBAERs comprising primary and / or secondary amines. The WBAERs may be in bead form, micronized powder form, or in some other solid form factors. In some embodiments of the invention, the WBAERs have a surface area of about 5-50 m2 / g. In some embodiments of the invention, the WBAER powders or beads are mixed with binders and fabricated into other solid forms such as sheets, tubes, monoliths, fibers, fibrils, nanofibers, or coatings which are then modified by treatment with the haloalcohol or halohydrin compounds. In some embodiments of the invention, the WBAER powders or beads are first modified by treatment with haloalcohol or halohydrin compounds and the modified WBAERs are then subsequently mixed with binders and fabricated into other solid forms such as sheets, tubes, monoliths, fibers, fibrils, nanofibers, or coatings.

[0012] The invention further relates to a method for improving the oxidation stability of a WBAER, the method comprising reacting the WBAER with a haloalcohol or a halohydrin compound under conditions sufficient to effect the modification reaction of the WBAER amine groups and the haloalcohol or halohydrin compound. In some embodiments of the invention, the air stability of the ion-exchange resins is significantly improved without impacting their CO2 uptake capacity or CO2 uptake kinetics significantly. In some embodiments of the invention, the reaction of a dilute solution of haloalcohol or halohydrin compounds with a WBAER, for example, may significantly improve its air stability at higher temperatures such as 50°C to 120°C. In some embodiments of the invention, the reaction of a dilutesolution of haloalcohol or halohydrin compounds with a WBAER, for example, may significantly improve its air stability at higher temperatures such as 60°C to 100°C. In some embodiments of the invention, the reaction of a dilute solution of haloalcohol or halohydrin compounds with a WBAER, for example, may significantly improve its air stability at higher temperatures such as 100°C. In some embodiments of the invention, the modification reaction is performed using a polar aprotic solvent. In some embodiments of the invention, the modification reaction is performed using a mixture of water and a polar aprotic solvent. The ratio of water to polar aprotic solvent in such cases may range from 99:1 to 1:99.

[0013] The invention further relates to a method for improving the oxidation stability of a WBAER, the method comprising suspending the WBAER in water and / or a polar organic solvent and reacting the suspended WBAER with a haloalcohol or a halohydrin compound to effect the modification reaction. Preferably, the polar organic solvent may be selected so that the haloalcohol or halohydrin compound has at least some solubility in the solvent. Nonlimiting examples of polar organic solvents that may be utilized in the invention include acetone, acetonitrile, dichloromethane, dimethylformamide (DMF), dimethylpropyleneurea, dimethyl sulfoxide (DMSO), ethyl acetate, hexamethylphosphoramide (HMPA), pyridine, sulfolane, and ethers such as tetrahydrofuran (THF), 2-methyltetrahydrofuran, or 1,3-dioxane. In some embodiments of the invention, the modification reaction is performed using a mixture of water and a polar aprotic solvent. Generally, after the reaction is complete, the resulting material is washed with water, an alcohol, or a polar organic solvent to remove any residual unreacted haloalcohol or halohydrin.

[0014] In some embodiments of the invention, the sorbent is a powder, bead, or other particulate form included within a tubular, disc, sheet, or pleated sheet shaped structure through which air may pass. In some embodiments of the invention, the sorbent is a structured sorbent material for allowing a high flow of air through the sorbent modules with a low pressure drop. In some embodiments of the invention, the structured sorbent material includes two or more sheets or plates supported within the sorbent modules in parallel. In some embodiments of the invention, the parallel sheets or plates include sorbents coated onto, impregnated in, or held within porous polymeric supports, woven glass, carbon, ceramic or polymeric fiber fabrics (including microfiber or nanofiber fabrics) or membranes, or glass, carbon, ceramic, or polymeric fiber felts. In some embodiments of the invention, the structured sorbent material is in the form of a monolith material with the sorbent coated onto, incorporated into, or forming the walls of the monolith material. In some embodiments of the invention, the structured sorbent material is in the form of a honeycomb material with the sorbent coated onto, incorporatedinto, or forming the walls of the supporting honeycomb material, in the form of an open-cell foam, and / or in the form of a reticulated sheet or structure through which air may flow. In some embodiments of the invention, the structured sorbent material is in the form of honeycomb material through which air may flow with the sorbent incorporated into or forming the walls of the honeycomb material. In some embodiments of the invention, the structured sorbent material is in the form of a three-dimensional web through which air may flow and wherein the web is woven or otherwise constructed from fibers and / or yarns comprising sorbent beads or particles coated onto, impregnated within, or held within the fiber and / or yarn bundles.

[0015] The invention further relates to a process for capturing CO2from point sources or directly from the atmosphere, the process comprising flowing a stream of ambient air over and / or through a sorbent, wherein the sorbent comprises a modified WBAER comprising a porous crosslinked styrene- divinylbenzene copolymer backbone further comprising primary and / or secondary amine groups and wherein at least some of the amine hydrogen groups of the primary and / or secondary amine groups are further modified via a reaction with a haloalcohol or halohydrin compound.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] These and other objects, features, and advantages of the invention will be more fully appreciated or become better understood when considered in conjunction with the accompanying drawings, wherein:

[0017] FIG. 1 shows an exemplary chemical modification of the amine groups of a weak-base anion exchange resin (WBAER) with haloalcohols.

[0018] FIG. 2 shows an exemplary chemical modification of the amine groups of a weak-base anion exchange resin (WBAER) with halohydrins.

[0019] FIG. 3 shows comparative retained CO2uptake curves for unmodified and modified WBAER LEWATIT® VP OC 1065 over several cycles of accelerated air stability testing.

[0020] FIG. 4A shows comparative CO2uptake curves for unmodified and modified WBAERs over several cycles of accelerated air stability testing.

[0021] FIG. 4B shows comparative retained CO2uptake curves for unmodified and modified WBAERs over several cycles of accelerated air stability testing.

[0022] FIG. 5A shows the effect of treatment of a WBAER with differing amounts of the haloalcohol 3-chloro-l-propanol (CIP) on initial CO2uptake capacity.

[0023] FIG. 5B shows the effect of treatment of a WBAER with differing amounts of the haloalcohol3-chloro-l-propanol (CIP) on the retained CO2 uptake after several cycles of accelerated air stability testing.

[0024] FIG. 6A shows the effect of treatment of a WBAER with linear (3-bromo-l-propanol, BrP, and 4-bromo-l-butanol, BrB) and branched (3-bromo-2-methyl-l-propanol, BMP) haloalcohols on initial CO2 uptake capacity.

[0025] FIG. 6B shows the effect of treatment of a WBAER with linear (3-bromo-l-propanol, BrP, and4-bromo-l-butanol, BrB) and branched (3-bromo-2-methyl-l-propanol, BMP) haloalcohols on the retained CO2 uptake after several cycles of accelerated air stability testing.DETAILED DESCRIPTION

[0026] Porous weak-base anion exchange resins (WBAERs) comprising primary and / or secondary amines have been shown to be sorbents for CO2 capture. WBAERs may also comprise tertiary amines, although tertiary amines are generally less useful for CO2capture than primary and secondary amines. In some embodiments of the invention, the porous WBAERs primarily comprise primary amine groups. In some embodiments of the invention, the WBAERs comprise primary amine groups, and no or substantially no (e.g., < 1%, < 0.5%, or < 0.1%; based on the total amount of amine groups present) secondary amine groups, that can be treated with haloalcohol or halohydrin compounds to yield modified resins demonstrating good CO2 adsorption / desorption performance along with improved oxidative stability. In some embodiments of the invention, at least about 90% (e.g., at least about 95%, at least about 98%, or at least about 99%) of the amine groups present in the porous WBAERs are primary amine groups.

[0027] In some embodiments of the invention, the porous WBAERs comprise both primary and secondary amine groups that can be treated with haloalcohol or halohydrin compounds to yield modified resins demonstrating good CO2 adsorption / desorption performance along with improved oxidative stability. In some embodiments, the WBAERs may comprise 1 - 99%, based on the total amount of amine groups present (e.g., 5 - 95%, 10 - 90%, 20 - 80%, 30 - 70%, 40 - 60%, or 45 - 55%), of primary amine groups and 99 - 1%, based on the total amount of amine groups present (e.g., 95 - 5%, 90 - 10%, 80 - 20%, 70 - 30%, 60 - 40%, or 55 - 45%), of secondary amine groups. In some embodiments of the invention, at least about 90% (e.g., at least about 95%, at least about 98%, or at least about 99%) of the amine groups present in the porous WBAERs are primary and / or secondary amine groups.

[0028] In some embodiments of the invention, the porous WBAERs comprise secondary amine groups, and no or substantially no (e.g., < 1%, < 0.5%, or < 0.1%; based on the total amount of amine groups present) primary amine groups, that can be treated with haloalcohol or halohydrin compounds to yield modified resins demonstrating good CO2adsorption / desorption performance along with improved oxidative stability. In some embodiments of the invention, at least about 90% (e.g., at least about 95%, at least about 98%, or at least about 99%) of the amine groups present in the porous WBAERs are secondary amine groups.

[0029] WBAERs useful for the invention are solids or gels at temperatures below about 120°C, and WBAERs that are solids are particularly preferred. Although WBAERs will often absorb considerable amounts of water, they are generally insoluble in water or, in some cases, form stable gels when swollen with water. WBAERs useful for the invention should remain insoluble in water at temperatures below about 120°C.

[0030] WBAERs comprise solid porous structures based on crosslinked polymeric backbones. In some embodiments of the invention, the polymeric backbones of the WBAERs comprise polymerized vinylic monomers. Such vinylic monomers include, but are not limited to, styrene, vinylamine, allylamine, acrylate, and methacrylate monomers and mixtures thereof. Crosslinking is achieved by copolymerizing the vinylic monomers with di- or tri-functional comonomers. Divinylbenzene (DVB) is the most common crosslinking comonomer utilized for the synthesis of WBAERs. DVB is commonly comprised of a mixture of m-DVB (i.e., 1,3-divinylbenzene) and p-DVB (i.e., 1,4-divinylbenzene). As produced commercially, the ratio of m-DVB to p-DVB typically ranges from about 1.5-2.5, although other ratios may be obtained or used. When used alone herein (i.e., without designating the isomeric form or forms), the terms divinylbenzene or DVB will refer to any mixture of m-DVB and p-DVB. The degree of crosslinking of the DVB copolymers can be controlled by varying the ratio of the vinylic and DVB comonomers. In some embodiments of the invention, at least about 1% (mole / mole) of DVB is utilized as a comonomer in the polymerization reaction to effect crosslinking. In some embodiments of the invention, at least about 2% (mole / mole) of DVB is utilized as a comonomer in the polymerization reaction to effect crosslinking. In some embodiments of the invention, at least about 5% (mole / mole) of DVB is utilized as a comonomer in the polymerization reaction to effect crosslinking. In some embodiments of the invention, between about 2% to 70% (mole / mole) of DVB is utilized as a comonomer in the polymerization reaction to effect crosslinking. In some embodiments of the invention, between about 5% to 50% (mole / mole) of DVB is utilized as a comonomer in the polymerization reaction to effect crosslinking. In some embodiments of the invention, between about10% to 35% (mole / mole) of DVB is utilized as a comonomer in the polymerization reaction to effect crosslinking.

[0031] Some WBAERs suitable for use in the invention comprise crosslinked polymeric backbones based on amine-containing vinyl monomers such as polyvinylamine or polyallylamine backbones crosslinked with DVB. The amine groups of such amine-containing vinyl monomers generally need to be copolymerized in a protected form but directly provide amine-containing WBAERs upon deprotection of the amine groups. For example, Chin ta pal I i, et al. in US Patent No. 11,612, 852, the disclosure of which is incorporated herein by reference, describes the synthesis of certain crosslinked poly(vinylamine-DVB) copolymers utilizing a protected form of vinylamine. In other cases, WBAERs suitable for use in the invention are derived by further functionalizing non-amine containing solid porous polymer materials. For example, in some embodiments of the invention, the porous WBAERs derive from a crosslinked polymeric backbone derived from the free radical copolymerization of styrene and DVB. As is known in the art, by performing the polymerization in suspension and incorporating various combinations of solvents, porogens, and stabilizers, the crosslinked styrene / DVB copolymers may be obtained as solid particles or beads of controlled size and porosity. In some embodiments of the invention, the porous WBAERs comprise a crosslinked polymeric backbone derived from the free radical copolymerization of styrene and DVB. In some embodiments of the invention, at least about 1% (mole / mole) of DVB is utilized as a comonomer in the polymerization reaction to effect crosslinking. In some embodiments of the invention, between about 2% to 70% (mole / mole) of DVB is utilized as a comonomer in the polymerization reaction to effect crosslinking. In some embodiments of the invention, between about 5% to 50% (mole / mole) of DVB is utilized as a comonomer in the polymerization reaction to effect crosslinking. In some embodiments of the invention, between about 5% to 25% (mole / mole) of DVB is utilized as a comonomer in the polymerization reaction to effect crosslinking. Although various synthetic methods have been described in the art, conversion of the crosslinked styrene / DVB copolymers to WBAERs is generally achieved via chloromethylation and amination. The aromatic groups present in the crosslinked styrene / DVB copolymers are first modified via chloromethylation in the presence of a Lewis acid catalyst. While not intending to be limiting, chloromethyl methyl ether or bis chloromethyl ether are commonly utilized as reagents in the chloromethylation reaction. The chloromethyl groups are then subsequently reacted with ammonia or amines, with elimination of hydrochloric acid, to yield an amine-containing WBAER. For WBAERs comprising poly(acrylate-DVB) or poly(methacrylate-DVB) copolymeric backbones, the reactive ester groups present in the acrylate and methacrylate groups may be further modified to incorporate amine groups.

[0032] The invention relates to new carbon dioxide adsorbents based on modified WBAERs comprising a crosslinked poly(styrene-divinylbenzene) skeleton containing appended primary and / or secondary amines. The WBAERS materials are insoluble in water and common organic solvents, have surface areas of 5 to 50 m2 / g, and can be in either bead or powder form. The WBAER materials are suspended in water or a polar organic solvent and treated with haloalcohol or halohydrin compounds to affect the functionalization. The modified materials exhibit significantly improved air stability of the ionexchange resins without much impact on their CO2 uptake capacity or CO2 uptake kinetics. The modified materials remain insoluble in water and common organic solvents and, therefore, are not susceptible to leaching under steam-based or moisture-based sorbent regeneration conditions.

[0033] WBAERs suitable for use in the invention are generally macroporous (e.g., having pore sizes greater than about 50 nm), although they may also possess some number of smaller pores. In general, the WBAERs useful in the invention will have a nitrogen content of about 2% to 35% by weight. In some embodiments of the invention, the WBAERs will have a nitrogen content ranging from about 3% to 30% by weight. In some embodiments of the invention, the WBAERs will have a nitrogen content ranging from about 5% to 25% by weight. In some embodiments of the invention, the WBAERs will have a nitrogen content of about 5% to 15% by weight. In some embodiments of the invention, the WBAERs will have a nitrogen content ranging from about 7% to 12% by weight. In some embodiments of the invention, the WBAERs will have a nitrogen content ranging from about 8% to 11% by weight. In some embodiments of the invention, the WBAERs will have a nitrogen content ranging from about 10% to 35% by weight. WO 2023 / 110520 (Vargas, et al.), the disclosure of which is incorporated herein by reference, describes the synthesis of polystyrene-divinylbenzene materials modified with amine groups and useful for CO2 capture over a wide humidity range. Several WBAERS are commercially available, including, for example, those sold under the following tradenames: LEWATIT® VP OC 1065 resin (Lanxess Deutschland GmbH) and PUROLITE® A109 and A110 resins (Purolite LLC).

[0034] Haloalcohol compounds are well known in the art and comprise molecules with at least one halogen group and at least one hydroxyl group attached to different carbon atoms within the molecule. The term halohydrin, in its broadest sense, is also used to refer to molecules with at least one halogen group and at least one hydroxyl group attached to different carbon atoms but more commonly is used to refer to a subset of haloalcohols wherein a halogen group and a hydroxyl group are attached to adjacent carbon atoms within the molecule. Certain haloalcohol and halohydrin compounds are commercially manufactured in high volumes as chemical precursors. Halohydrin compounds arecommonly synthesized via the addition of halogen and water to olefins or the reaction of epoxides with hydrohalic acids, as nonlimiting examples.

[0035] In some embodiments of the invention, a haloalcohol suitable for use in the invention is a compound of formula (I):wherein:X is a halogen; n is an integer between 0 and 18; andR1, R2, Rn, Rn, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0036] In formula (I), X is a halogen. X may be chlorine (Cl), bromine (Br), iodine (I), or fluorine (F). In a preferred embodiment of the invention, X of formula (I) is chlorine (Cl), bromine (Br), or iodine (I). In some embodiments of the invention, X of formula (I) is chlorine. In some embodiments of the invention, X of formula (I) is bromine. In some embodiments of the invention, X of formula (I) is iodine. In some embodiments of the invention, X of formula (I) is fluorine.

[0037] In formula (I), n is an integer between 0 and 18. In some embodiments of the invention, n is an integer between 1 and 18. In some embodiments of the invention, n is an integer between 1 and 12. In some embodiments of the invention, n is an integer between 1 and 10. In some embodiments of the invention, n is an integer between 1 and 8. In some embodiments of the invention, n is an integer between 1 and 6. In some embodiments of the invention, n is an integer between 1 and 4. In some embodiments of the invention, n is 1, 2, or 3. In some embodiments of the invention, n is 1 or 2. In some embodiments of the invention, n is 1. In some embodiments of the invention, n is 2. In some embodiments of the invention, n is 0 and the haloalcohol is a halohydrin.

[0038] In formula (I), R1, R2, Rn, Rn', R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. When n is greater than 1, each Rnand each Rnmay be the same or different. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. Insome embodiments of the invention, the hydrocarbyl is selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n- octyl, isooctyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl. A substituted hydrocarbyl may be a hydrocarbyl substituted with one or more substituent groups, wherein substituted means that at least one hydrogen atom bound to a carbon atom is replaced with one or more non-hydrogen substituents. Examples of such substituents include, without limitation: fluoro (— F), hydroxy (—OH), Ci-Cis alkoxy, C2-C18 alkenyloxy, C5-C14 aryloxy, C6-C20 aralkyloxy, C6-C20 alkaryloxy, formyl (— C(=O)H), C2-C18 acyl (-C(=O)Y), amino (— N H2), mono-(Ci-Ci8alkyl)-substituted amino, di-(Ci-Ci8alkyl)-substituted amino, mono-(C5-Ci4aryl)-substituted amino, di-(C5-Ci4 aryl)-substituted amino, (Ci-Ci8alkyl)(C5-Ci4aryl )- substituted amino, cyano (-C=N), and nitro (-NO2), wherein Y is a hydrocarbyl group. In some embodiments of the invention, neither R1nor R2should have a hydroxy group in the a-position (i.e., on the carbon attached directly to the CX group).

[0039] In some embodiments of the invention, both R1and R2of formula (I) are hydrogen. In some embodiments of the invention, both R3and R4of formula (I) are hydrogen. In some embodiments of the invention, all of the Rnand Rngroups of formula (I) are hydrogen. In some embodiments of the invention, at least one of R1and R2of formula (I) and at least one of R3and R4of formula (I) are hydrogen. In some embodiments of the invention, both of R1and R2of formula (I) and at least one of R3and R4of formula (I) are hydrogen. In some embodiments of the invention, both R1and R2of formula (I) and both R3and R4of formula (I) are hydrogen. In some embodiments of the invention, all of the R1, R2, Rn, Rn-, R3, and R4groups of formula (I) are hydrogen.

[0040] In some embodiments of the invention, the haloalcohol compound molecule reacting with the amine hydrogen groups present in a particle of a WBAER is a compound of formula (II):wherein:X is a halogen; n is an integer between 0 and 18; andR is selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0041] In formula (II), X is a halogen. X may be chlorine (Cl), bromine (Br), iodine (I), or fluorine (F). In a preferred embodiment of the invention, X of formula (II) is chlorine (Cl), bromine (Br), or iodine (I). In some embodiments of the invention, X of formula (II) is chlorine. In some embodiments of the invention, X of formula (II) is bromine. In some embodiments of the invention, X of formula (II) is iodine. In some embodiments of the invention, X of formula (II) is fluorine.

[0042] In formula (II), n is an integer between 0 and 18. In some embodiments of the invention, n is an integer between 1 and 18. In some embodiments of the invention, n is an integer between 1 and 12. In some embodiments of the invention, n is an integer between 1 and 10. In some embodiments of the invention, n is an integer between 1 and 8. In some embodiments of the invention, n is an integer between 1 and 6. In some embodiments of the invention, n is an integer between 1 and 4. In some embodiments of the invention, n is 1, 2, or 3. In some embodiments of the invention, n is 1 or 2. In some embodiments of the invention, n is 1. In some embodiments of the invention, n is 2. In some embodiments of the invention, n is 0 and the haloalcohol is a halohydrin.

[0043] In formula (II), R is selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, R is a hydrocarbyl selected from the group consisting of methyl, ethyl, n- propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n-octyl, isooctyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl. In some embodiments of the invention, R is a substituted hydrocarbyl selected from the group consisting of fluoro (— F), hydroxy (- OH), Ci-Cis alkoxy, C2-C18 alkenyloxy, C5-C14 aryloxy, C6-C20 aralkyloxy, C6-C20 alkaryloxy, formyl (-C(=O)H), C2-C18 acyl (-C(=O)Y), amino (-NH2), mono-(Ci-Ci8alkyl)-substituted amino, di-(Ci-Ci8alkyl)-substituted amino, mono-(C5-Ci4 aryl)-substituted amino, di-(C5-Ci4 aryl)-substituted amino, (Ci-Ci8al kyl )(C5-Ci4aryl )- substituted amino, cyano (-C=N), and nitro (-NO2), wherein Y is a hydrocarbyl group.

[0044] In some embodiments of the invention, a halohydrin suitable for use in the invention is a compound of formula (III):wherein:X is a halogen; andRi, R2, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0045] In formula (III), X is a halogen. X may be chlorine (Cl), bromine (Br), iodine (I), or fluorine (F). In a preferred embodiment of the invention, X of formula (III) is chlorine (Cl), bromine (Br), or iodine (I). In some embodiments of the invention, X of formula (III) is chloride. In some embodiments of the invention, X of formula (III) is bromine. In some embodiments of the invention, X of formula (III) is iodine. In some embodiments of the invention, X of formula (III) is fluorine.

[0046] In formula (III), Ri, R2, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, the hydrocarbyl is selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n- octyl, and isooctyl. A substituted hydrocarbyl may be a hydrocarbyl substituted with one or more substituent groups, wherein substituted means that at least one hydrogen atom bound to a carbon atom is replaced with one or more non-hydrogen substituents. Examples of such substituents include, without limitation: fluoro (-F), hydroxy (-OH), Ci-Cig alkoxy, C2-C18alkenyloxy, C5-C14 aryloxy, Ce-Czo aralkyloxy, C6-C2o alkaryloxy, formyl (-C(=O)H), C2-C18acyl (-C(=O)Y), amino (— N H2), mono- (C1-C18 alkyl)-substituted amino, di-(Ci-Ci8alkyl )-substituted amino, mono-(C5-Ci4 aryl)-substituted amino, di-(C5-Ci4aryl)-substituted amino, (Ci-C18alkyl)(C5-Ci4 aryl)-substituted amino, cyano (-C N), and nitro (-NO2), wherein Y is a hydrocarbyl group.

[0047] In some embodiments of the invention, both Ri and R2of formula (III) are hydrogen. In some embodiments of the invention, at least one of Ri and R2of formula (III) and at least one of R8andR4of formula (III) are hydrogen. In some embodiments of the invention, both Ri and R2of formula (III) and at least one of R3 and R4of formula (III) are hydrogen.

[0048] In another embodiment of the invention, a halohydrin suitable for use in the invention is a compound of formula (IV):wherein:X is a halogen; andRi, R2, R3, Rs, Re, and R7are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0049] In formula (IV), X is a halogen. X may be chlorine (Cl), bromine (Br), iodine (I), or fluorine (F). In a preferred embodiment of the invention, X of formula (IV) is chlorine (Cl), bromine (Br), or iodine (I). In some embodiments of the invention, X of formula (IV) is chloride. In some embodiments of the invention, X of formula (IV) is bromine. In some embodiments of the invention, X of formula (IV) is iodine. In some embodiments of the invention, X of formula (IV) is fluorine.

[0050] In formula (IV), Ri, R2, R3, Rs, Rs, and R7are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, the hydrocarbyl is selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n-octyl, and isooctyl. A substituted hydrocarbyl may be a hydrocarbyl substituted with one or more substituent groups, wherein substituted means that at least one hydrogen atom bound to a carbon atom is replaced with one or more non-hydrogen substituents. Examples of such substituents include, without limitation: fluoro (-F), hydroxy (-OH), Ci-Cig alkoxy, C2-Ci8alkenyloxy, C5-C14 aryloxy, C6-C20aralkyloxy, C6-C20alkaryloxy, formyl (-C(=O)H), C2-Ci8acyl (-C(=O)Y), amino (-NH2), mono- (Ci-Cis alkyl)-substituted amino, di-(Ci-Ci8alkyl )-substituted amino, mono-(C5-Ci4 aryl)-substitutedamino, di-(C5-Ci4aryl)-substituted amino, (Ci-Ci8alkyl)(C5-Ci4aryl)-substituted amino, cyano (-C=N), and nitro (-NO2), wherein Y is a hydrocarbyl group.

[0051] In some embodiments of the invention, the haloalcohol compound has a single hydroxy group. Nonlimiting examples of such haloalcohols suitable for use in the invention include 3-chloro-l- propanol, 3-bromo-l-propanol, l-bromo-2-propanol, 4-chloro-l-butanol, 4-bromo-l-butanol, 3-bromo- 2-methyl-l-propanol, and 3-bromo-2,2-dimethyl-l-propanol. In some embodiments of the invention, the haloalcohol may have two or more hydroxy groups. Nonlimiting examples of such haloalcohols suitable for use in the invention include 4-bromo-l,2-butanediol and 6-bromo-l,2-hexanediol. In some embodiments of the invention, the halohydrin compound has a single hydroxy group. Nonlimiting examples of such halohydrins suitable for use in the invention include 2-chloroethanol, 2-bromoethanol, and l-bromo-2-propanol. In some embodiments of the invention, the halohydrin may have two or more hydroxy groups. Nonlimiting examples of such halohydrins suitable for use in the invention include 3- bromopropane-l,2-diol and 2-bromo-l,4-butanediol. In some embodiments of the invention, the halohydrin is 3-bromopropane-l,2-diol.

[0052] As shown in FIG. 1, the amine hydrogen groups present in a particle of WBAER can be reacted with a haloalcohol compound, in this example depicted with the representative, but nonlimiting, haloalcohol X-CH2(CH2)nCH(OH)R, with the release of hydrohalic acid (HX). In some embodiments of the invention, the haloalcohol compound is X-CH2(CH2)nCH(OH)R, wherein X is a halogen, and R is selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. In some embodiments of the invention, the halogen is selected from the group consisting of chlorine (Cl), bromine (Br), iodine (I), and fluorine (F), preferably chlorine (Cl), bromine (Br), and iodine (I). In some embodiments of the invention, R is hydrogen. In some embodiments of the invention, R is a hydrocarbyl selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n-octyl, and isooctyl. In some embodiments of the invention, R is a substituted hydrocarbyl selected from the group consisting of fluoro (-F), hydroxy (-OH), Ci-Cis alkoxy, C2-C18 alkenyloxy, C5-C14 aryloxy, Cg-C2o aralkyloxy, Cg-C2o alkaryloxy, formyl (-C(=O)H), C2-C18 acyl (- C(=O)Y), amino (-NH2), mono-(Ci-Ci8alkyl)-substituted amino, di-(Ci-Ci8alkyl)-substituted amino, mono- (C5-C14 aryl)-substituted amino, di-(C5-Ci4aryl)-substituted amino, (Ci-Ci8alkyl)(C5-Ci4 aryl)-substituted amino, cyano (-C=N), and nitro (-NO2), wherein Y is a hydrocarbyl group.

[0053] In some embodiments of the invention, the haloalcohol compound reacting with the amine hydrogen groups present in a particle of a WBAER is a compound of formula (I). In some embodimentsof the invention, the haloalcohol compound reacting with the amine hydrogen groups present in a particle of a WBAER is a compound of formula (II).

[0054] As shown in FIG. 2, the amine hydrogen groups present in a particle of WBAER can be reacted with a halohydrin molecule, in this example depicted with the representative, but nonlimiting, halohydrin X-CH2CH(OH)R, with the release of hydrohalic acid (HX). In some embodiments of the invention, the halohydrin compound is X-CH2CH(OH)R, wherein X is a halogen, and R is selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. In some embodiments of the invention, the halogen is selected from the group consisting of chlorine (Cl), bromine (Br), iodine (I), and fluorine (F), preferably chlorine (Cl), bromine (Br), and iodine (I). In some embodiments of the invention, R is hydrogen. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, R is a hydrocarbyl selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n- butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n-octyl, and isooctyl. In some embodiments of the invention, R is a substituted hydrocarbyl selected from the group consisting of fluoro (-F), hydroxy (-OH), Ci-Cis alkoxy, C2-Ci8alkenyloxy, C5-C14 aryloxy, C6-C2o aralkyloxy,C6-C2o alkaryloxy, formyl (-C(=O)H), C2-Ci8acyl (-C(=O)Y), amino (-NH2), mono-(Ci-Ci8alkyl)-substituted amino, di-(Ci-Ci8al kyl)-substituted amino, mono-(C5-Ci4aryl)-substituted amino, di-(C5-Ci4aryl)- substituted amino, (Ci-C18al kyl)(C5-Ci4aryl)-substituted amino, cyano (-C=N), and nitro (-NO2), wherein Y is a hydrocarbyl group.

[0055] In another embodiment of the invention, the halohydrin molecule reacting with the amine hydrogen groups present in a particle of a WBAER is a compound of formula (III). In another embodiment of the invention, the halohydrin molecule reacting with the amine hydrogen groups present in a particle of a WBEAR is a compound of formula (IV).

[0056] In some embodiments of the invention, the primary amine groups present in a particle of WBAER suitable for the invention have the structure of formula (V):wherein the primary amine groups of formula (V) are bound to a porous crosslinked copolymer backbone.

[0057] In some embodiments of the invention, the secondary amine groups present in a particle ofWBAER suitable for the invention have the structure of formula (VI):wherein R5is a hydrocarbyl group or a substituted hydrocarbyl group, and wherein the secondary amine groups of formula (VI) are bound to a porous crosslinked copolymer backbone.

[0058] In formula (VI), R5is a hydrocarbyl group or a substituted hydrocarbyl group. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, R5of formula (VI) is a hydrocarbyl selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n-octyl, isooctyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl. In some embodiments of the invention, R5of formula (VI) is a substituted hydrocarbyl, wherein one or more of the hydrogen atoms bound to a carbon atom of the hydrocarbyl group is replaced with one or more non-hydrogen substituents selected from the group consisting of fluoro (— F), chloro (—Cl), Ci-Cig alkoxy, C2-Cig alkenyloxy, C5-C14 aryloxy, Cg-C2o aralkyloxy, Cg- C2o alkaryloxy, formyl (-C(=O)H), C2-Ci acyl (-C(=O)Y), cyano (-C N), and nitro (-NO2), wherein Y is a hydrocarbyl group.

[0059] The modified WBAERs formed from the reaction of WBAERs with haloalcohols comprise hydroxyalkyl groups appended to the amine groups of the WBAERs. In some embodiments of the invention, one or more WBAER primary amine groups of formula (V) each reacts with a haloalcohol compound of formula (I) to yield modified amine groups. In some embodiments of the invention, the modified amine groups have the structure of formula (VII):wherein: n is an integer between 0 and 18; andR1, R2, Rn, Rn', R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the modified amine groups of formula (VII) are bound to a porous crosslinked copolymer backbone.

[0060] In formula (VII), n is an integer between 0 and 18. In some embodiments of the invention, n is an integer between 1 and 18. In some embodiments of the invention, n is an integer between 1 and 12. In some embodiments of the invention, n is an integer between 1 and 10. In some embodiments of the invention, n is an integer between 1 and 8. In some embodiments of the invention, n is an integer between 1 and 6. In some embodiments of the invention, n is an integer between 1 and 4. In some embodiments of the invention, n is 1, 2, or 3. In some embodiments of the invention, n is 1 or 2. In some embodiments of the invention, n is 1. In some embodiments of the invention, n is 2. In some embodiments of the invention, n is 0 and the haloalcohol is a halohydrin.

[0061] In formula (VII), R1, R2, Rn, Rn‘, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. When n is greater than 1, each Rnand each Rnmay be the same or different. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, the hydrocarbyl is selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n- octyl, isooctyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl. A substituted hydrocarbyl may be a hydrocarbyl substituted with one or more substituent groups, wherein substituted means that at least one hydrogen atom bound to a carbon atom is replaced with one or more non-hydrogen substituents. Examples of such substituents include, without limitation: fluoro (-F), hydroxy (-OH), Ci-Cis alkoxy, C2-C18 alkenyloxy, C5-C14 aryloxy, C6-C20 aralkyloxy, C6-C20 alkaryloxy, formyl (-C(=O)H),C2-C18acyl (-C(=O)Y), amino (-NH2), mono-(Ci-Ci8alkyl)-substituted amino, di-(Ci-C18alkyl)-substituted amino, mono-(C5-Ci4 aryl)-substituted amino, di-(C5-Ci4 aryl)-substituted amino, (Ci-Ci8alkyl)(C5-Ci4 aryl )- substituted amino, cyano (— C=N), and nitro (- NO2), wherein Y is a hydrocarbyl group. In some embodiments of the invention, neither R1nor R2should have a hydroxy group in the a-position (i.e., on the carbon attached directly to the CX group).

[0062] In some embodiments of the invention, one or more WBAER primary amine groups of formula (V) each reacts with two haloalcohol compounds of formula (I) to yield modified amine groups. In some embodiments of the invention, the modified amine groups have the structure of formula (VIII):wherein: n is an integer between 0 and 18; andR1, R2, Rn, Rn, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the modified amine groups of formula (VIII) are bound to a porous crosslinked copolymer backbone.

[0063] In formula (VIII), n is an integer between 0 and 18. In some embodiments of the invention, n is an integer between 1 and 18. In some embodiments of the invention, n is an integer between 1 and 12. In some embodiments of the invention, n is an integer between 1 and 10. In some embodiments of the invention, n is an integer between 1 and 8. In some embodiments of the invention, n is an integer between 1 and 6. In some embodiments of the invention, n is an integer between 1 and 4. In some embodiments of the invention, n is 1, 2, or 3. In some embodiments of the invention, n is 1 or 2. In some embodiments of the invention, n is 1. In some embodiments of the invention, n is 2. In some embodiments of the invention, n is 0 and the haloalcohol is a halohydrin.

[0064] In formula (VIII), R1, R2, Rn, Rn, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. When n is greater than 1, each Rnand each Rnmay be the same or different. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic,saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, the hydrocarbyl is selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n- octyl, isooctyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl. A substituted hydrocarbyl may be a hydrocarbyl substituted with one or more substituent groups, wherein substituted means that at least one hydrogen atom bound to a carbon atom is replaced with one or more non-hydrogen substituents. Examples of such substituents include, without limitation: fluoro (-F), hydroxy (-OH), C1-C18 alkoxy, C2-Ci8alkenyloxy, C5-C14 aryloxy, C6-C20aralkyloxy, C3-C20alkaryloxy, formyl (-C(=O)H), C2-C18acyl (-C(=O)Y), amino (— NHz), mono-(Ci-Ci8alkyl)-substituted amino, di-(Ci-Ci8alkyl)-substituted amino, mono-(C5-CMaryl)-substituted amino, di-(C5-Ci4aryl)-substituted amino, (Ci-Ci8al kyl )(C5-Ci4aryl )- substituted amino, cyano (-C=N), and nitro (-NO2), wherein Y is a hydrocarbyl group. In some embodiments of the invention, neither R1nor R2should have a hydroxy group in the a-position (i.e., on the carbon attached directly to the CX group).

[0065] In some embodiments of the invention, one or more WBAER secondary amine groups of formula (VI) each reacts with a haloalcohol compound of formula (I) to yield modified amine groups. In some embodiments of the invention, the modified amine groups have the structure of formula (IX):wherein: n is an integer between 0 and 18; andR1, R2, Rn, Rn', R3, R4, and R5are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the modified amine groups of formula (IX) are bound to a porous crosslinked copolymer backbone.

[0066] In formula (IX), n is an integer between 0 and 18. In some embodiments of the invention, n is an integer between 1 and 18. In some embodiments of the invention, n is an integer between 1 and 12. In some embodiments of the invention, n is an integer between 1 and 10. In some embodiments of the invention, n is an integer between 1 and 8. In some embodiments of the invention, n is an integer between 1 and 6. In some embodiments of the invention, n is an integer between 1 and 4. In someembodiments of the invention, n is 1, 2, or 3. In some embodiments of the invention, n is 1 or 2. In some embodiments of the invention, n is 1. In some embodiments of the invention, n is 2. In some embodiments of the invention, n is 0 and the haloalcohol is a halohydrin.

[0067] In formula (IX), R1, R2, Rn, Rn, R3, R4, and R5are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. When n is greater than 1, each Rnand each Rnmay be the same or different. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, the hydrocarbyl is selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n- octyl, isooctyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl. A substituted hydrocarbyl may be a hydrocarbyl substituted with one or more substituent groups, wherein substituted means that at least one hydrogen atom bound to a carbon atom is replaced with one or more non-hydrogen substituents. Examples of such substituents include, without limitation: fluoro (-F), hydroxy (-OH), Ci-Cw alkoxy, C2-C18 alkenyloxy, C5-C14 aryloxy, C6-C20 aralkyloxy, C6-C20 alkaryloxy, formyl (-C(=O)H), C2-C18 acyl (-C(=O)Y), amino (-NH2), mono-(Ci-Ci8alkyl)-substituted amino, di-(Ci-Ci8alkyl)-substituted amino, mono-(C5-Ci4 aryl)-substituted amino, di-(C5-Ci4 aryl)-substituted amino, (Ci-Cis al kyl )(C5-Ci4aryl )- substituted amino, cyano (-C=N), and nitro (-NO2), wherein Y is a hydrocarbyl group. In some embodiments of the invention, neither R1nor R2should have a hydroxy group in the a-position (i.e., on the carbon attached directly to the CX group).

[0068] Depending on the relative amount of haloalcohol or halohydrin added and the total reaction time and temperature, at least some or nearly all of the amine hydrogen groups of the primary and / or secondary amine groups of a WBAER may become modified. In some embodiments of the invention, the reaction temperature may be around room temperature and the reaction time may be a few hours. More specifically, the reaction temperature may be between 20° to 60° C and the reaction time between 2 to 24 hours. In some embodiments of the invention, the reaction temperature may be between 20° to 40° C and the reaction time between 2 to 24 hours. In some embodiments of the invention, the reaction temperature may be between 20° to 35° C and the reaction time between 2 to 24 hours. In some embodiments of the invention, excess haloalcohol or halohydrin is added to substitute every hydrogen. As shown above, when the amine groups are primary amine groups (i.e., the amine has two hydrogen groups), one or both of the hydrogen groups of the amine may react with thehaloalcohol or halohydrin. In some embodiments of the invention, ranging from about 2-100% of the amine hydrogen groups are modified. In some embodiments of the invention, ranging from about 2-50% of the amine hydrogen groups are modified. In some embodiments of the invention, ranging from about 2-35% of the amine hydrogen groups are modified. In some embodiments of the invention, ranging from about 3-25% of the amine hydrogen groups are modified. In some embodiments of the invention, between about 5% to 100% of the amine hydrogen groups are modified. In some embodiments of the invention, between about 10% to 90% of the amine hydrogen groups are modified.In some embodiments of the invention, between about 15% to 75% of the amine hydrogen groups are modified. In some embodiments of the invention, between about 10% to 50% of the amine hydrogen groups are modified. In some embodiments of the invention, between about 50% to 95% of the amine hydrogen groups are modified. In some embodiments of the invention, at least about 25% of the amine hydrogen groups are modified. In some embodiments of the invention, at least about 50% of the amine hydrogen groups are modified. In some embodiments of the invention, at least about 75% of the amine hydrogen groups are modified. In some embodiments of the invention, at least about 2% of the amine hydrogen groups are modified. In some embodiments of the invention, at least about 5% of the amine hydrogen groups are modified. In some embodiments of the invention, at least about 10% of the amine hydrogen groups are modified. In some embodiments of the invention, no more than about 5% of the amine hydrogen groups are modified. In some embodiments of the invention, no more than about 10% of the amine hydrogen groups are modified. In some embodiments of the invention, no more than about 25% of the amine hydrogen groups are modified.

[0069] In general, the WBAER may be suspended in water or a polar organic solvent with the haloalcohol or halohydrin and stirred to effect the modification reaction. Preferably, the polar organic solvent may be selected so that the haloalcohol or halohydrin has at least some solubility in the solvent. Nonlimiting examples of polar organic solvents that may be utilized in the invention include acetone, acetonitrile, dichloromethane, dimethylformamide (DMF), dimethylpropyleneurea, dimethyl sulfoxide (DMSO), ethyl acetate, hexamethylphosphoramide (HMPA), pyridine, sulfolane, and ethers (e.g., tetrahydrofuran, 2-methyltetrahydrofuran, or 1,3-dioxane). In some embodiments of the invention, the modification reaction is performed using tetrahydrofuran (THF), 2-methyltetrahydrofuran, or 1,3- dioxane. In some embodiments of the invention, the modification reaction is performed using tetrahydrofuran (THF). In some embodiments of the invention, the modification reaction is performed using a mixture of water and a polar aprotic solvent. The ratio of water to polar aprotic solvent in such cases may range from 99:1 to 1:99. In some embodiments of the invention, the ratio of water to polaraprotic solvent may range from 9:1 to 1:99. In some embodiments of the invention, the ratio of water to polar aprotic solvent may range from 1:1 to 1:99. After the reaction is complete, the resulting material is treated with a solution of base to remove the eliminated hydrohalic acid. Nonlimiting examples of basic reagents that may be utilized in the invention include sodium hydroxide (NaOH), potassium hydroxide (KOH), sodium carbonate (NazCC ), and sodium bicarbonate (NaHCOj). The base solution will generally utilize water or an alcohol (e.g., methanol, ethanol, iso-propanol, etc.) as the solvent. Generally, after the reaction is complete, the resulting modified material is washed with water, an alcohol, or a polar aprotic solvent to remove any residual haloalcohol, halohydrin, hydrohalic acid, and / or base.

[0070] In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (VII). In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (VIII). In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (IX). In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (VII) and formula (VIII). In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (VIII) and formula (IX). In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (VII) and formula (IX). In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (VII), formula (VIII), and formula (IX). In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise unmodified amine groups of formula (V). In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise unmodified amine groups of formula (VI). In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise unmodified amine groups of formula (V) and formula (VI). In some embodiments of the invention, the modified WBEAR sorbents of the present invention comprise at least one of an unmodified amine group selected from the group consisting of formula (V) and formula (VI) and at least one modified amine group selected from the group consisting of formula (VII), formula (VIII), and formula (IX).

[0071] In some embodiments of the invention, the modified WBAER sorbents of the invention comprise modified amine groups that have the structure of formula (X):wherein: n is an integer between 1 and 18; andR is selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the modified amine groups of formula (X) are bound to a porous crosslinked copolymer backbone.

[0072] In formula (X), n is an integer between 1 and 18. In some embodiments of the invention, n is an integer between 1 and 12. In some embodiments of the invention, n is an integer between 1 and 10. In some embodiments of the invention, n is an integer between 1 and 8. In some embodiments of the invention, n is an integer between 1 and 6. In some embodiments of the invention, n is an integer between 1 and 4. In some embodiments of the invention, n is 1, 2, or 3. In some embodiments of the invention, n is 1 or 2. In some embodiments of the invention, n is 1. In some embodiments of the invention, n is 2.

[0073] In formula (X), R is selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, R is a hydrocarbyl selected from the group consisting of methyl, ethyl, n- propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n-octyl, isooctyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl. In some embodiments of the invention, R is a substituted hydrocarbyl wherein one or more of the hydrogen atoms bound to a carbon atom of the hydrocarbyl is replaced with one or more non-hydrogen substituents selected from the group consisting of fluoro (-F), hydroxy (-OH), Ci-Cig alkoxy, Cj-Cig alkenyloxy, C5-C14 aryloxy, Cg-Czo aralkyloxy, Cg-Czo alkaryloxy, formyl (-C(=O)H), Cz-Cig acyl (-C(=O)Y), amino (-NH2), mono- (Ci-Cig alkyl)-substituted amino, di-(Ci-Ci8alkyl )-substituted amino, mono-(C5-Ci4aryl)-substituted amino, di-(C5-Ci4aryl)-substituted amino, (Ci-Cig alkyl)(C5-Ci4 aryl)-substituted amino, cyano (-CEN), and nitro (-NO2), wherein Y is a hydrocarbyl group.10074] In some embodiments of the invention, the modified WBAER sorbents of the invention comprise modified amine groups that have the structure of formula (XI):wherein: each n is independently selected from an integer between 1 and 18; and each R is independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the modified amine groups of formula (XI) are bound to a porous crosslinked copolymer backbone.

[0075] In formula (XI), each n is independently selected from an integer between 1 and 18. In some embodiments of the invention, n is an integer between 1 and 12. In some embodiments of the invention, n is an integer between 1 and 10. In some embodiments of the invention, n is an integer between 1 and 8. In some embodiments of the invention, n is an integer between 1 and 6. In some embodiments of the invention, n is an integer between 1 and 4. In some embodiments of the invention, n is 1, 2, or 3. In some embodiments of the invention, n is 1 or 2. In some embodiments of the invention, n is 1. In some embodiments of the invention, n is 2.

[0076] In formula (XI), each R is independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, R is a hydrocarbyl selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n- octyl, isooctyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl. In some embodiments of the invention, R is a substituted hydrocarbyl wherein one or more of the hydrogen atoms bound to a carbon atom of the hydrocarbyl is replaced with one or more non-hydrogen substituents selected from the group consisting of fluoro (-F), hydroxy (-OH), Ci-Cig alkoxy, Cj-Cig alkenyloxy, C5-C14 aryloxy, Cg-Czo aralkyloxy, Cg-Czo alkaryloxy, formyl (-C(=O)H), Cz-Cig acyl (-C(=O)Y), amino (-NH2), mono-(Ci-Cig al kyl)-substituted amino, di-(Ci-Ci8alkyl )-substituted amino, mono-(C5-Ci4 aryl)-substituted amino, di-(C5-Ci4 aryl)-substituted amino, (Ci-Ci8alkyl)(C5-Ci4 aryl)-substituted amino, cyano (-CEN), and nitro (-NO2), wherein Y is a hydrocarbyl group.

[0077] In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (X) and formula (XI).

[0078] In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups that have the structure of formula (XII):wherein: n is an integer between 1 and 18; andR and R5are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the modified amine groups of formula (XII) are bound to a porous crosslinked copolymer backbone.

[0079] In formula (XII), n is an integer between 1 and 18. In some embodiments of the invention, n is an integer between 1 and 12. In some embodiments of the invention, n is an integer between 1 and 10. In some embodiments of the invention, n is an integer between 1 and 8. In some embodiments of the invention, n is an integer between 1 and 6. In some embodiments of the invention, n is an integer between 1 and 4. In some embodiments of the invention, n is 1, 2, or 3. In some embodiments of the invention, n is 1 or 2. In some embodiments of the invention, n is 1. In some embodiments of the invention, n is 2.

[0080] In formula (XII), R and R5are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. A hydrocarbyl may be a univalent hydrocarbyl radical containing 1 to about 24 carbon atoms, preferably 1 to about 18 carbon atoms, more preferably 1 to about 12 carbon atoms, and most preferably 1 to about 8 carbon atoms, including linear, branched, cyclic, saturated, and unsaturated species, such as alkyl groups, alkenyl groups, aryl groups, and the like. In some embodiments of the invention, the hydrocarbyl is selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, neopentyl, n-hexyl, n-heptyl, n- octyl, isooctyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl. A substituted hydrocarbylmay be a hydrocarbyl substituted with one or more substituent groups, wherein substituted means that at least one hydrogen atom bound to a carbon atom is replaced with one or more non-hydrogen substituents. Examples of such substituents include, without limitation: fluoro (-F), hydroxy (-OH), Ci-Cig alkoxy, C2-Ci8alkenyloxy, C5-C14 aryloxy, C6-C20aralkyloxy, C6-C20alkaryloxy, formyl (-C(=O)H), C2-C18acyl (-C(=O)Y), amino (-NH2), mono-(Ci-Ci8alkyl)-substituted amino, di-(Ci-C18alkyl)-substituted amino, mono-(C5-Ci4 aryl)-substituted amino, di-(C5-Ci4 aryl)-substituted amino, (Ci-Ci8al kyl )(C5-Ci4aryl )- substituted amino, cyano (-C N), and nitro (-NO2), wherein Y is a hydrocarbyl group.

[0081] In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups that have the structure of formula (XIII):wherein the modified amine groups of formula (XIII) are bound to a porous crosslinked copolymer backbone.

[0082] In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups that have the structure of formula (XIV):- OHwherein the modified amine groups of formula (XIV) are bound to a porous crosslinked copolymer backbone.

[0083] In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (XIII) and formula (XIV).

[0084] In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups that have the structure of formula (XV):wherein the modified amine groups of formula (XV) are bound to a porous crosslinked copolymer backbone.

[0085] In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups that have the structure of formula (XVI):wherein the modified amine groups of formula (XIV) are bound to a porous crosslinked copolymer backbone.

[0086] In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (XV) and formula (XVI). In some embodiments of the invention, the modified WBAER sorbents of the present invention comprise modified amine groups of formula (XII), formula (XIV), formula (XV) and formula (XVI).

[0087] The modified WBAERs of the invention provide good performance and improved lifetime when utilized as sorbents in processes to capture CO2from air or flue gases. The modified WBAERS of the invention are insoluble in water and are therefore stable in humid environments and are not prone to leaching when utilized in CO2capture processes utilizing water or steam. FIG. 4A, FIG. 5A, and FIG. 6A show the results of accelerated aging tests (see Examples 7, 8, and 10 below) for samples of WBAERs modified with haloalcohols. Even though some of the modified-WBAERs initially showed lower CO2capacity than the original WBAER, their CO2capacity decreased less over several cycles of accelerated aging and ultimately became better than that of the original WBAER. All of the modified-WBAER materials exhibit a higher retained CO2uptake over several cycles of the accelerated aging conditions than the original WBAER as seen in FIG. 4B, FIG. 5B, and FIG. 6B.

[0088] The modified WBAERS of the invention may be utilized in powder, bead, or pellet form in fluidized bed or packed bed configurations. The modified WBAERs of the invention may be fabricated into a structured sorbent material to allow a high flow of air through the sorbent with a low pressure drop. In some embodiments of the invention, the structured sorbent material is in the form of sheets or plates that comprise sorbents coated onto, impregnated into, or held within porous polymeric supports; woven glass, carbon, ceramic or polymeric fiber fabrics (including microfiber or nanofiber fabrics) or membranes; or glass, carbon, ceramic, or polymeric fiber felts. In some embodiments of the invention, the structured sorbent material is in the form of a monolith material with the sorbent coated onto, incorporated into, or forming the walls of the monolith material. In some embodiments of theinvention, the structured sorbent material is in the form of a honeycomb material with the sorbent coated onto, incorporated into, or forming the walls of the supporting honeycomb material, in the form of an open-cell foam, or in the form of a reticulated sheet or structure through which air may flow. In some embodiments of the invention, the structured sorbent material includes two or more sheets or plates supported in a parallel arrangement within a structure through which air may pass between the parallel sheets or plates. In some embodiments of the invention, the sorbent is a powder, bead, or other particulate form included within a tubular, disc, sheet, or pleated sheet shaped structure through which air may pass. In some embodiments of the invention, the structured sorbent material is in the form of a three-dimensional web through which air may flow and wherein the web is woven or otherwise constructed from fibers and / or yarns comprising sorbent beads or particles coated onto, impregnated within, or held within the fiber and / or yarn bundles.

[0089] In some embodiments of the invention, the modified WBAERs are utilized as sorbents in a temperature swing adsorption (TSA) CO? capture process. The TSA process generally involves three steps: (i) adsorption; (ii) desorption via heated purge; and (iii) cooling. During adsorption, a flue gas or ambient air is pulled or pushed through a reactor containing the sorbent using a fan or blower, and CO? is adsorbed. Adsorption variables include air flow rate, sorbent capture efficiency, sorbent capacity, and adsorption time. In some embodiments of the invention, adsorption time is 15 to 120 minutes and adsorption temperature is ambient air temperature at -20° to 45° C. During desorption, air flow is stopped, and a heated purge gas is passed through the sorbent to effect desorption and to sweep desorbed CO? out of the reactor. In some embodiments of the invention, the purge gas is an inert gas such as nitrogen to prevent oxidation of the sorbent during heating. In some embodiments of the invention, the purge gas is a product gas (i.e., CO?) so as not to dilute the purity of the desorbed product. In some embodiments of the invention, thermal jackets or surface heaters can be utilized to help heat the sorbent modules during the purge step. Desorption variables include purge gas, purge gas flow rate, temperature, and desorption time. In some embodiments of the invention, desorption time is 15 to 120 minutes and desorption temperature is 80° to 120° C. In some embodiments of the invention, desorption time is 15 to 120 minutes and desorption temperature is 60° to 105° C. In some embodiments of the invention, desorption time is 15 to 120 minutes and desorption temperature is 75° to 100° C. After desorption, the reactor is purged with a cool stream of air or inert gas, depending upon the oxygen sensitivity of the sorbent, to cool the system back to ambient. In some embodiments of the invention, the system is cooled to between 50° to 60° C. In some embodiments of the invention, the system is cooled to between 60° to 80° C. For a given sorbent and reactor system, the adsorption time,air flow rate, purge gas temperature and flow rate, desorption time, and cooling time are typical process parameters that can be monitored and controlled.

[0090] In some embodiments of the invention, the modified WBAERs are utilized as sorbents in a temperature vacuum swing adsorption (TVSA) CO2capture process. The TVSA process generally involves four steps: (i) adsorption; (ii) evacuation; (iii) desorption; and (iv) cooling. During adsorption, a flue gas or ambient air is pulled or pushed through a reactor containing the sorbent using a fan or blower, and CO2 is adsorbed. Adsorption variables include air flow rate, sorbent capture efficiency, sorbent capacity, and adsorption time. In some embodiments of the invention, adsorption time is 15 to 120 minutes and adsorption temperature is ambient air temperature at -20° to 45° C. During evacuation, the reactor is sealed, and air is evacuated using a vacuum pump to remove dead air and non-condensable gas impurities. The sorbent in the reactor is then heated, which desorbs CO2, which is removed through the vacuum system. In some embodiments of the invention, thermal jackets or surface heaters can be utilized to heat the sorbent modules during the evacuation step. Desorption variables include evacuation level, temperature, and desorption time. In some embodiments of the invention, desorption time is 15 to 120 minutes and desorption temperature is 80° to 120° C. In some embodiments of the invention, desorption time is 15 to 120 minutes and desorption temperature is 60° to 105° C. In some embodiments of the invention, desorption time is 15 to 120 minutes and desorption temperature is 75° to 100° C. After desorption, the reactor is purged with a cool stream of air or inert gas, depending upon the oxygen sensitivity of the sorbent, to cool the system back to ambient. In some embodiments of the invention, the system is cooled to between 50° to 60° C. In some embodiments of the invention, the system is cooled to between 60° to 80° C. For a given sorbent and reactor system, the adsorption time, air flow rate, evacuation level, desorption temperature and time, and cooling time are typical process parameters that can be monitored and controlled.

[0091] In some embodiments of the present invention, the modified WBAERs are utilized as sorbents in a steam-assisted temperature vacuum swing adsorption (S-TVSA) CO2capture process, wherein a steam purge is utilized to heat the sorbent and help sweep away CO2as it desorbs from the sorbent during a regeneration step. The S-TVSA process generally involves four steps: (i) adsorption; (ii) evacuation; (iii) steam-assisted desorption; and (iv) evaporative cooling. During adsorption, a flue gas or ambient air is pulled or pushed through a reactor containing the sorbent using a fan or blower, and CO2is adsorbed. Adsorption variables include air flow rate, sorbent capture efficiency, sorbent capacity, and adsorption time. In some embodiments of the invention, adsorption time is 15 to 120 minutes and adsorption temperature is ambient air temperature at -20° to 45° C. During evacuation, the reactor issealed, and air is evacuated using a vacuum pump to remove dead air and non-condensable gas impurities. Desorption occurs in two steps: re-pressurization and purge. Steam is introduced into the reactor to raise the pressure to the desired desorption pressure, heating the sorbent in the process. In some embodiments of the invention, the desired desorption pressure is about 0.8 to 1.3 bar. In some embodiments of the invention, the desired desorption pressure is about 0.6 to 1.1 bar. In some embodiments of the invention, the desired desorption pressure is about 0.7 to 0.9 bar. The reactor outlet is then opened to begin purge, which desorbs CO2 and sweeps it into a wet CO2 product stream. Steam is an effective carrier to sweep away gaseous CO2as it is being desorbed, thereby promoting increased desorption by way of reducing the partial pressure of the gas above the sorbent. Desorption variables include evacuation level, steam temperature / pressure, and purge time. In some embodiments of the invention, desorption time is 15 to 120 minutes and desorption temperature is 80° to 120° C. In some embodiments of the invention, desorption time is 15 to 120 minutes and desorption temperature is 60° to 105° C. In some embodiments of the invention, desorption time is 15 to 120 minutes and desorption temperature is 75° to 100° C. After desorption, the reactor is evacuated again using a vacuum pump to desorb water from the sorbent and rapidly cool it. In some embodiments of the invention, the system is cooled to between 50° to 60° C. In some embodiments of the invention, the system is cooled to between 60° to 80° C. The evaporation of this water removes heat from the sorbent, mitigating the risk of sorbent oxygenation when air is readmitted for the next adsorption cycle. For a given sorbent and reactor system, the adsorption time, air flow rate, evacuation level, steam temperature / pressure, steam purge rate and time, and evaporative cooling time are typical process parameters that are monitored and controlled.EXAMPLES

[0092] In the following examples, efforts have been made to ensure accuracy with respect to numbers used (e.g., amounts, temperature, etc.) but some experimental error and deviation should be accounted for. The examples are to be considered as not being limiting of the invention described herein.

[0093] General Procedures. LEWATIT® VP OC 1065 weak base anion exchange resin (SI) with a macroporous styrene / divinylbenzene backbone structure and comprising primary amine groups was obtained from Lanxess in spherical bead form (bead size range 0.3-1.25 mm; BET surface area «43 m2 / g; pore volume «0.64 cm3 / g; pore diameter ~57 nm). A sample of weak base anion exchange polymer (S2) with a styrene / divinylbenzene backbone structure and comprising primary amine groups was obtained in bead form (bead size range 0.35-0.85 mm; BET surface area ~15.8 m2 / g). A portion of the 52 beadswas milled to a powder form (S2P). Two samples of a macroporous weak base anion exchange polymer (S3 and S3') with a styrene / divinylbenzene backbone structure and comprising primary amine groups in free base form was obtained as beads (bead size range 0.3-1.2 mm) and milled to a powder form. Accelerated cyclic air stability (ACAS) testing was performed using thermogravimetric analysis (TGA) with a Q500TGA from TA Instruments. To perform the test, approximately 20-30 mg of sorbent sample was placed into the sample holder in the TGA under a purge of dry air (without CO?) at 100 mL / min. The sample temperature was then ramped to 100°C at 10°C / min, held for 60 min at 100°C, cooled to 40°C at 10°C / min, and then held at 40°C for 15 min. The purge gas was then changed from dry air to a mixture of 15% CO2 and 85% nitrogen for 30 min - the sample weight increased during this time as the sorbent adsorbed CO2. The purge gas was then changed back to dry air and the sample temperature was ramped as described previously - the sample weight decreased during this time as the sorbent desorbed CO2. This test was repeated for 10 additional cycles to measure how sorbent performance degraded over time due to oxidation or other thermal degradation pathways. The retained CO2 uptake was expressed as a percentage of the uptake at the 11thcycle relative to the initial uptake (1stcycle).

[0094] Example 1: Accelerated Cyclic Air Stability of Unmodified WBAER

[0095] A sample of as-received Lewatit® VP OC 1065 weak-base anion exchange resin (SI) was dried at 40°C in an oven (Si-Dry). A sample of the dry Si-Dry was then stirred in tetrahydrofuran (THF) for 18 hours at room temperature, filtered, washed, and then redried at 40°C in an oven (Sl-THF). Samples of the weak-base anion exchange resins S2 and S2P were dried at 40°C in an oven (S2-Dry and S2P-Dry, respectively). Samples of the dry S2-Dry were then stirred in water (S2-Water) or methanol (S2-MeOH) for 18 hours at room temperature, filtered, washed, and then redried at 40°C in an oven. A sample of the milled weak-base anion exchange resin (S3) was dried at 40°C in an oven (S3-Dry), stirred in water for 18 hours at room temperature, filtered, washed, and then redried at 40°C in an oven (S3- Water). A sample of the milled weak-base anion exchange resin (S3') was dried at 40°C in an oven, stirred in water for 18 hours at room temperature, filtered, washed, and then redried at 40°C in an oven (S3' -Water). Samples of the Si-Dry, Sl-THF, S2-Dry, S2-Water, S2-MeOH, S3-Dry, S3-Water and S3'- Water materials were then tested in TGA for ACAS for 11 cycles as described above, and the results are summarized in Table 1.Table 1

[0096] Example 2: Modification of WBAER SI with 3-Bromo-l,2-Propanediol (2.0 mmol / g) in THF

[0097] In a 100 mL beaker, 2.78 g dry Lewatit® VP OC 1065 weak-base anion exchange resin (Si-Dry) was added into 20 mL tetrahydrofuran (THF). After 1 minute of agitation in ambient air, 5.56 mmol 3-bromo-l,2-propanediol (BrPD) was added and the reaction stirred for 18 hours at room temperature. The THF was filtered from the solid material, and then 50 mL of water was added along with 5.56 mmol potassium hydroxide and the mixture stirred for 1 hour at room temperature. The solid product was filtered, washed with water and then with THF, and dried at 40°C in the oven and was tested in TGA for ACAS for 11 cycles as described above. This modified material showed an initial CO2uptake of 1.82 mmol / g and a retained CO2uptake of 95%. Most of the decrease in the initial CO2uptake can be attributed to the increase in mass of the modified WBAER after modification (e.g., assuming complete incorporation of the halohydrin reagent, and loss of HBr, the adjusted initial CO2uptake would be estimated to be about 2.09 mmol / g based on the initial WBAER weight). FIG. 3 shows comparative retained CO2uptake curves for unmodified WBAER LEWATIT® VP OC 1065 (Sl-THF from Example 1) and the modified WBAER LEWATIT® VP OC 1065 from this Example 2 (Sl-BrPD) over the 11 cycles of ACAS testing and demonstrates the improved stability of the modified WBAER material.

[0098] Example 3: Modification of WBAER S3' with 3-Bromo-l,2-Propanediol (2.0 mmol / g) in THF

[0099] In a 100 mL beaker, 2.66 g dry S3' (milled) was added into 50 mL tetra hydrofuran (THF).After 1 minute of agitation in ambient air, 5.34 mmol 3-bromo-l,2-propanediol (BrPD) was added and the reaction stirred for 18 hours at room temperature. The THF was filtered from the solid material, andthen 50 mL of water was added along with 5.34 mmol potassium hydroxide and the mixture stirred for 1 hour at room temperature. The solid product was filtered, washed with water and then with THF, and dried at 40°C in the oven and was tested in TGA for ACAS for 11 cycles as described above. This modified material showed an initial CO2uptake of 1.99 mmol / g and a retained CO2uptake of 85%. Most of the decrease in the initial CO2uptake can be attributed to the increase in mass of the modified WBAER after modification (e.g., assuming complete incorporation of the halohydrin reagent, and loss of HBr, the adjusted initial CO2uptake would be estimated to be about 2.29 mmol / g based on the initial WBAER weight).

[0100] Example 4: Modification of WBAER S3' with 3-Bromo-l,2-Propanediol (2.0 mmol / g) in THF

[0101] In a 100 mL beaker, 2.66 g dry S3' (milled) was added into 20 mL tetra hydrofuran (THF). After 1 minute of agitation in ambient air, 5.34 mmol 3-bromo-l,2-propanediol (BrPD) was added and the reaction stirred for 18 hours at room temperature. The THF was filtered from the solid material, and then 50 mL of water was added along with 5.34 mmol potassium hydroxide and the mixture stirred for 1 hour at room temperature. The solid product was filtered, washed with water and then with THF, and dried at 40°C in the oven and was tested in TGA for ACAS for 11 cycles as described above. This modified material showed an initial CO2uptake of 1.95 mmol / g and a retained CO2uptake of 87%. Most of the decrease in the initial CO2uptake can be attributed to the increase in mass of the modified WBAER after modification (e.g., assuming complete incorporation of the halohydrin reagent, and loss of HBr, the adjusted initial CO2uptake would be estimated to be about 2.24 mmol / g based on the initial WBAER weight).

[0102] Example 5: Modification of WBAER SI with 3-Bromo-l-Propanol (2.0 mmol / g) in THF

[0103] In a 100 mL beaker, 2.78 g Si-Dry was added into 20 mL tetrahydrofuran (THF). After 1 minute of agitation in ambient air, 5.56 mmol 3-bromo-l-propanol (BrP), with a purity of 99.3%, was added to the suspension and the reaction stirred for 18 hours at room temperature. The THF was filtered from the solid material, and then 50 mL of water was added along with 5.56 mmol potassium hydroxide (KOH) and the mixture stirred for 1 hour at room temperature. The solid product was filtered, washed with water and then with THF, and dried at 40° C in the oven and was tested in TGA for ACAS for 11 cycles as described above. This modified material showed an initial CO2uptake of 1.79 mmol / g and a retained CO2uptake of 94%. The decrease in the initial CO2uptake as expressed per gram of sorbent material can be at least somewhat attributed to the increase in mass of the modified WBAER after modification (e.g., assuming complete incorporation of the haloalcohol reagent, and loss of HBr, theadjusted initial C02uptake would be estimated to be about 2.00 mmol / g based on the initial WBAER weight).

[0104] Example 6: Modification of WBAER S3 with 3-Bromo-l-Propanol (2.0 mmol / g) in THF

[0105] The procedure of Example 5 was followed using 2.66 g S3-Dry, 5.34 mmol BrP (with a purity of 99.3%), and 5.34 mmol KOH. This modified material (S3-BrP) was tested in TGA for ACAS for 11 cycles as described above and showed an initial CO2uptake of 2.24 mmol / g (2.50 mmol / g adjusted for the theoretical weight increase during modification) and a retained CO2uptake of 93%.

[0106] Example 7: Modification of WBAER S3 with 3-Chloro-l-Propanol (2.0 mmol / g) in THF

[0107] The procedure of Example 5 was followed using 2.66 g S3-Dry, 5.34 mmol 3-chloro-l- propanol (Cl P, with a purity of 99.7%), and 5.34 mmol KOH. This modified material (S3-CIP-2) was tested in TGA for ACAS for 11 cycles as described above and showed an initial CO2uptake of 2.39 mmol / g (2.67 mmol / g adjusted for the theoretical weight increase during modification) and a retained CO2uptake of 95%. FIG. 4A shows the effect of 11 cycles of ACAS testing on the CO2uptake performance (unadjusted) of unmodified WBAER S3-Water (from Example 1) and the S3-BrP and S3-CIP-2 modified materials from Examples 6 and 7. FIG. 4B compares the retained CO2uptake performance for the same samples over the 11 cycles of ACAS testing.

[0108] Example 8: Modification of WBAER S3 with 3-Chloro-l-Propanol (4.0 mmol / g) in THF

[0109] The procedure of Example 5 was followed using 2.66 g S3-Dry, 10.64 mmol 3-chloro-l- propanol (CIP, with a purity of 99.7%), and 10.64 mmol KOH. This modified material (S3-CIP-4) was tested in TGA for ACAS for 11 cycles as described above and showed an initial CO2uptake of 2.31 mmol / g (2.58 mmol / g adjusted for the theoretical weight increase during modification) and a retained CO2uptake of 95%. FIG. 5A shows the effect of 11 cycles of ACAS testing on the CO2uptake performance (unadjusted) of unmodified WBAER S3-Water (from Example 1) and the S3-CIP-2 and S3- CIP-4 modified materials from Examples 7 and 8. FIG. 5B compares the retained CO2uptake performance for the same samples over the 11 cycles of ACAS testing.

[0110] Example 9: Modification of WBAER S3 with 4-Bromo-l-Butanol (2.0 mmol / g) in THF

[0111] The procedure of Example 5 was followed using 2.66 g S3-Dry, 5.34 mmol 4-bromo-l- butanol (BrB, with a purity of about 85%), and 5.34 mmol KOH. This modified material (S3-BrB) was tested in TGA for ACAS for 11 cycles as described above and showed an initial CO2uptake of 2.20 mmol / g (2.52 mmol / g adjusted for the theoretical weight increase during modification) and a retained CO2uptake of 93%.

[0112] Example 10: Modification of WBAER S3 with (R)-3-Bromo-2-Methyl-l-Propanol (2.0 mmol / g) in THF

[0113] The procedure of Example 5 was followed using 2.66 g S3-Dry, 5.34 mmol (R)-3-bromo-2- methyl-l-propanol (BMP, with a purity of 98.5%), and 5.34 mmol KOH. This modified material (S3-BMP) was tested in TGA for ACAS for 11 cycles as described above and showed an initial CO2 uptake of 2.38 mmol / g (3.07 mmol / g adjusted for the theoretical weight increase during modification) and a retained CO2 uptake of 91%. FIG. 6A shows the effect of 11 cycles of ACAS testing on the CO2 uptake performance (unadjusted) of unmodified WBAER S3-Water (from Example 1) and the S3-BrP, S3-BrB, and S3-BMP modified materials from Examples 6, 9, and 10. FIG. 6B compares the retained CO2 uptake performance for the same samples over the 11 cycles of ACAS testing.

[0114] Example 11: Modification of WBAER SI with 4-Bromo-l-Butanol (2.0 mmol / g) in THF

[0115] The procedure of Example 5 was followed using 2.77 g Si-Dry, 5.54 mmol 4-bromo-l-butanol (BrB, with a purity of about 85%), and 5.54 mmol KOH. This modified material was tested in TGA for ACAS for 11 cycles as described above and showed an initial CO2uptake of 1.72 mmol / g (1.97 mmol / g adjusted for the theoretical weight increase during modification) and a retained CO2 uptake of 94%.

[0116] Example 12: Modification of WBAER SI with 3-Chloro-l-Propanol (2.0 mmol / g) in THF

[0117] The procedure of Example 5 was followed using 2.78 g Si-Dry, 5.56 mmol 3-chloro-l-propanol (CIP, with a purity of 99.7%), and 5.56 mmol KOH. This modified material was tested in TGA for ACAS for 11 cycles as described above and showed an initial CO2 uptake of 1.91 mmol / g (2.13 mmol / g adjusted for the theoretical weight increase during modification) and a retained CO2 uptake of 93%.

[0118] Example 13: Modification of WBAER S2P with 3-Chloro-l-Propanol (4.0 mmol / g) in Water

[0119] In a 50 ml beaker, 0.91 g S2P-Dry and 0.46 g sodium carbonate were added into 10 ml of distilled water. After 10 minutes of agitation at 60°C, 3.63 mmol 3-chloro-l-propanol (CIP) was added to the suspension and the reaction stirred for 6 hours at 60°C. The liquid was filtered from the solid material, which was then washed with distilled water. The washed solid was added to a50 ml beaker along with 10 mL distilled water and 3.63 mmol potassium hydroxide (KOH) and the mixture stirred for 30 minutes at room temperature. The solid product was filtered, washed with water, air dried, and was tested in TGA for ACAS for 11 cycles as described above. This modified S2P material showed an initial CO2 uptake of 1.95 mmol / g and a retained CO2 uptake of 88%.

[0120] Example 14: Simulated DAC Performance of Modified WBAERs

[0121] Simulated DAC testing (400 ppm CO2at 20% relative humidity) was performed using thermogravimetric analysis (TGA) with a Q5000 TGA, with humidity control chamber, from TAInstruments. To perform the test, approximately 20-30 mg of sorbent sample was placed into the sample holder in the TGA under a purge of dry nitrogen at 150 mL / min. The sample temperature was then ramped to 85° C, held for 60 min at 85° C, and then cooled to 30° C to prepare the sample for adsorption studies. The sample chamber was then equilibrated with nitrogen gas maintained at 20% relative humidity until the sample stopped gaining weight (the weight gain during this step corresponding to the "H?O uptake"). The purge gas was then changed to a mixture of 400 ppm CO? in nitrogen maintained at 20% relative humidity. The sample weight increased during this time as the sorbent adsorbed CO2. The sample was held until it reached full equilibrium with CO? and H2O and stopped gaining further weight. The CO? uptake was calculated from total CO?+H?O mass gain minus the H?O uptake. Testing was performed with the baseline S3-Water (Example 1) material and with modified WBAERs S3-BrP (Example 6), S3-CIP-2 (Example 7), and S3-BrB (Example 9). The results are summarized in Table 2.Table 2

[0122] As those skilled in the art will appreciate, numerous modifications and variations of the invention are possible in light of these teachings, and all such are contemplated hereby. All of the references cited herein are incorporated by reference herein for all purposes, or at least for their teachings in the context presented.

[0123] Exemplary Embodiments of the Invention

[0124] El. A water insoluble modified weak-base anion exchange resin comprising a porous crosslinked styrene-divinylbenzene copolymer backbone further comprising primary and / or secondary amine groups and wherein at least some of the amine hydrogen groups of the primary and / or secondary amine groups are further modified via a reaction with a halohydrin compound.

[0125] E2. The water insoluble modified weak-base anion exchange resin of El, wherein the halohydrin compound is a compound of formula (III):whereinX is a halogen; andRi, R2, R3, and R4are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0126] E3. The water insoluble modified weak-base anion exchange resin of El, wherein the halohydrin compound is a compound of formula (IV):whereinX is a halogen; andRi, R2, 3, Rs, Re, and R7are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0127] E4. The water insoluble modified weak-base anion exchange resin of E2 or E3, wherein X is a halogen selected from the group consisting of chlorine (Cl), bromine (Br), iodine (I), and fluorine (F).

[0128] E5. The water insoluble modified weak-base anion exchange resin of E2, wherein both Ri and R2are hydrogen.

[0129] E6. The water insoluble modified weak-base anion exchange resin of E2, wherein at least one of Ri and 2 and at least one of R3 and R4are hydrogen.

[0130] E7. The water insoluble modified weak-base anion exchange resin of El, wherein the halohydrin compound is selected from the group consisting of 2-chloroethanol, 2-bromoethanol, and 1- bromo-2-propanol.

[0131] E8. The water insoluble modified weak-base anion exchange resin of El, wherein the halohydrin compound is selected from the group consisting of 3-bromopropane-l,2-diol and 2-bromo- 1,4-butanediol.

[0132] E9. A method for improving the oxidation stability of a weak-base anion exchange resin, the method comprising reacting a weak-base anion exchange resin with a halohydrin compound.

[0133] E10. The method of E9, wherein the weak-base anion exchange resin comprises a porous crosslinked styrene-divinylbenzene copolymer backbone further comprising primary and / or secondary amine groups.

[0134] Ell. The method of E9 or E10, wherein the halohydrin compound is a compound of formula (III):whereinX is a halogen; andRi, z, R3, and R4are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0135] E12. The method of E9 or E10, wherein the halohydrin compound is a compound of formula(IV):whereinX is a halogen; andRi, R2, R3, Rs, Re, and R7are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0136] E13. The method of Ell or E12, wherein X is a halogen selected from the group consisting of chlorine (Cl), bromine (Br), iodine (I), and fluorine (F).

[0137] E14. The method of E9 or E10, wherein the halohydrin compound is selected from the group consisting of 2-chloroethanol, 2-bromoethanol, and l-bromo-2-propanol.

[0138] E15. The method of E9 or E10, wherein the halohydrin compound is selected from the group consisting of 3-bromopropane-l,2-diol and 2-bromo-l,4-butanedioL

[0139] E16. A method for improving the oxidation stability of a weak-base anion exchange resin, the method comprising suspending the weak-base anion exchange resin in water or a polar organic solvent and reacting the suspended weak-base anion exchange resin with a halohydrin compound.

[0140] E17. The method of E16, wherein the weak-base anion exchange resin comprises a porous crosslinked styrene-divinylbenzene copolymer backbone further comprising primary and / or secondary amine groups.

[0141] E18. The method of E16 or E17, wherein the halohydrin compound is a compound of formula (III):whereinX is a halogen; andRi, 2, R3, and R4are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0142] E19. The method of E16 or E17, wherein the halohydrin compound is a compound of formula (IV):whereinX is a halogen; andRl, R2, R3, R5, R6, and R7 are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0143] E20. The method of E18 or E19, wherein X is a halogen selected from the group consisting of chlorine (Cl), bromine (Br), iodine (I), and fluorine (F).

[0144] E21. The method of E16 or E17, wherein the halohydrin compound is selected from the group consisting of 2-chloroethanol, 2-bromoethanol, and l-bromo-2-propanol.

[0145] E22. The method of E16 or E17, wherein the halohydrin compound is selected from the group consisting of 3-bromopropane-l,2-diol and 2-bromo-l,4-butanedioL

[0146] E23. The method of any one of E16-E22, wherein the polar organic solvent is an ether.

[0147] E24. The method of any one of E16-E23, further comprising treating with a solution of base to remove a hydrohalic acid.

[0148] E25. A process for capturing CO2from the atmosphere, the process comprising flowing a stream of ambient air over or through a sorbent, wherein the sorbent comprises a modified weak-base anion exchange resin comprising a porous crosslinked styrene-divinylbenzene copolymer backbone further comprising primary and / or secondary amine groups and wherein at least some of the amine hydrogen groups of the primary and / or secondary amine groups are further modified via a reaction with a halohydrin compound.

[0149] E26. The process of E25, wherein the halohydrin compound is a compound of formula (III):whereinX is a halogen; andRi, R2, R3, and R4are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0150] E27. The process of E25, wherein the halohydrin compound is a compound of formula (IV):whereinX is a halogen; andRi, R2, R3, s, Rs, and R7are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0151] E28. The process of E26 or E27, wherein X is a halogen selected from the group consisting of chlorine (Cl), bromine (Br), iodine (I), and fluorine (F).

[0152] E29. The process of E25, wherein the halohydrin compound is selected from the group consisting of 2-chloroethanol, 2-bromoethanol, and l-bromo-2-propanol.

[0153] E30. The process of E25, wherein the halohydrin compound is selected from the group consisting of 3-bromopropane-l,2-diol and 2-bromo-l,4-butanediol.

[0154] E31. The water insoluble modified weak-base anion exchange resin of E2, wherein both Ri and R? are hydrogen and at least one of R3 and R« are hydrogen.

[0155] E32. A water insoluble modified weak-base anion exchange resin comprising a porous crosslinked polymeric backbone further comprising primary and / or secondary amine groups and wherein at least some of the amine hydrogen groups of the primary and / or secondary amine groups are further modified via a reaction with a haloalcohol compound.

[0156] E33. The water insoluble modified weak-base anion exchange resin of E32, wherein the porous crosslinked polymeric backbone is based on vinylic monomers crosslinked with divinylbenzene.

[0157] E34. The water insoluble modified weak-base anion exchange resin of E33, wherein the vinylic monomers are selected from the group consisting of styrene, vinylamine, allyamine, acrylate, and methacrylate monomers.

[0158] E35. The water insoluble modified weak-base anion exchange resin of E34, wherein the vinylic monomers are styrene.

[0159] E36. The water insoluble modified weak-base anion exchange resin of E33, wherein the vinylic monomers are amine-containing vinyl monomers.

[0160] E37. The water insoluble modified weak-base anion exchange resin of E36, wherein the amine-containing vinyl monomers are polyvinylamine or polyallylamine.

[0161] E38. The water insoluble modified weak-base anion exchange resin of any of E32-E37, wherein the haloalcohol compound is a compound of formula (I):whereinX is a halogen; n is an integer between 0 and 18; andR1, R2, Rn, Rn', R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0162] E39. The water insoluble modified weak-base anion exchange resin of E38, wherein both R1and R2are hydrogen.

[0163] E40. The water insoluble modified weak-base anion exchange resin of E38, wherein both R3and R4are hydrogen.

[0164] E41. The water insoluble modified weak-base anion exchange resin of E38, wherein at least one of R1and R2and at least one of R3and R4are hydrogen.

[0165] E42. The water insoluble modified weak-base anion exchange resin of E38, wherein both ofR1and R2and at least one of R3and R4are hydrogen.

[0166] E43. The water insoluble modified weak-base anion exchange resin of E38, wherein R1, R2,R3, and R4are each hydrogen.

[0167] E44. The water insoluble modified weak-base anion exchange resin of E38, wherein the Rnand Rngroups are each hydrogen.

[0168] E45. The water insoluble modified weak-base anion exchange resin of E38, wherein R1, R2,R3, R4, Rn, and Rnare each hydrogen.

[0169] E46. The water insoluble modified weak-base anion exchange resin of any of E32-E37, wherein the haloalcohol compound has a single hydroxy group.

[0170] E47. The water insoluble modified weak-base anion exchange resin of E46, wherein the haloalcohol compound is selected from the group consisting of 3-chloro-l-propanol, 3-bromo-l- propanol, l-bromo-2-propanol, 4-chloro-l-butanol, 4-bromo-l-butanol, 3-bromo-2-methyl-l-propanol, and 3-bromo-2,2-dimethyl-l-propanol.

[0171] E48. The water insoluble modified weak-base anion exchange resin of any of E32-E37, wherein the haloalcohol compound has two or more hydroxy groups.

[0172] E49. The water insoluble modified weak-base anion exchange resin of E48, wherein the haloalcohol compound is selected from the group consisting of 4-bromo-l,2-butanediol and 6-bromo- 1,2-hexanediol.

[0173] E50. A method for improving the oxidation stability of a weak-base anion exchange resin, the method comprising reacting a weak-base anion exchange resin with a haloalcohol compound.

[0174] E51. The method of E50, wherein the weak-base anion exchange resin comprises a porous crosslinked styrene-divinylbenzene copolymer backbone further comprising primary and / or secondary amine groups.

[0175] E52. The method of E50, wherein the weak-base anion exchange resin comprises a porous crosslinked polymeric backbone based on amine-containing vinyl monomers crosslinked with divinylbenzene.

[0176] E53. The method of any of E50-E52, wherein the haloalcohol compound is a compound of formula (I):whereinX is a halogen; n is an integer between 0 and 18; andR1, R2, Rn, Rn, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0177] E54. A method for improving the oxidation stability of a weak-base anion exchange resin, the method comprising suspending the weak-base anion exchange resin in a polar aprotic solvent and reacting the suspended weak-base anion exchange resin with a haloalcohol compound.

[0178] E55. The method of E54, wherein the weak-base anion exchange resin comprises a porous crosslinked styrene-divinylbenzene copolymer backbone further comprising primary and / or secondary amine groups.

[0179] E56. The method of E54, wherein the weak-base anion exchange resin comprises a porous crosslinked polymeric backbone based on amine-containing vinyl monomers crosslinked with divinylbenzene.

[0180] E57. The method of E54, wherein the haloalcohol compound is a compound of formula (I):whereinX is a halogen; n is an integer between 0 and 18; andR1, R2, Rn, Rn’, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0181] E58. The method of any one of E54-E57, wherein the polar aprotic solvent is acetone, acetonitrile, dichloromethane, dimethylformamide (DMF), dimethylpropyleneurea, dimethyl sulfoxide (DMSO), ethyl acetate, hexamethylphosphoramide (HMPA), pyridine, sulfolane, and ethers, such as tetrahydrofuran (THF), 2-methyltetrahydrofuran, or 1,3-dioxane.

[0182] E59. A water insoluble modified weak-base anion exchange resin comprising: a porous crosslinked copolymer backbone; one or more primary and / or secondary amine groups; and one or more modified amine groups, wherein at least one of the modified amine groups has the structure of formula (VII):wherein n is an integer between 1 and 18; andR1, R2, Rn, Rn', R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the one or more primary and / or secondary amine groups and the one or more modified amine groups are each bound to the porous crosslinked copolymer backbone.

[0183] E60. The water insoluble modified weak-base anion exchange resin of E59, wherein the water insoluble modified weak-base anion exchange resin further comprises one or more additional modified amine groups, wherein at least one of the additional modified amine groups has the structure of formula (VIII):wherein n is an integer between 1 and 18; andR1, R2, Rn, Rn', R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the one or more additional modified amine groups are each bound to the porous crosslinked copolymer backbone.

[0184] E61. The water insoluble modified weak-base anion exchange resin of E59 or E60, wherein the weak-base anion exchange resin comprises a porous crosslinked styrene-divinylbenzene copolymer backbone further comprising primary and / or secondary amine groups.

[0185] E62. The water insoluble modified weak-base anion exchange resin of E59 or E60, wherein the water insoluble modified weak-base anion exchange resin further comprises crosslinked polymeric backbones based on amine-containing vinyl monomers crosslinked with divinylbenzene.

[0186] E63. A process for capturing CO? from the atmosphere, the process comprising flowing a stream of flue gas or ambient air over and / or through a sorbent contained within a reactor, wherein the sorbent comprises a modified weak-base anion exchange resin comprising a porous crosslinked polymeric backbone further comprising primary and / or secondary amine groups and wherein at least some of the amine hydrogen groups of the primary and / or secondary amine groups are further modified via a reaction with a haloalcohol compound or a halohydrin compound.

[0187] E64. The process of E63, further comprising using a steam purge to heat the sorbent and help sweep away CO? as it desorbs from the sorbent during a regeneration step.

[0188] E65. The process of E63 or E64, wherein the porous crosslinked polymeric backbone is based on vinylic monomers crosslinked with divinylbenzene.

[0189] E66. The process of E65, wherein the vinylic monomers are selected from the group consisting of styrene, vinylamine, allylamine, acrylate, and methacrylate monomers.

[0190] E67. The process of E65, wherein the vinylic monomers are styrene.

[0191] E68. The process of E65, wherein the vinylic monomers are amine-containing vinyl monomers.

[0192] E69. The process of E68, wherein the amine-containing vinyl monomers are polyvinylamine or polyallylamine.

[0193] E70. The process of any of E63-E69, wherein at least about 90% of the amine groups present in the porous crosslinked polymeric backbone prior to modification are primary amine groups.

[0194] E71. The process of any of E63-E70, wherein the haloalcohol compound is a compound of formula (I):wherein:X is a halogen; n is an integer between 0 and 18; andR1, R2, Rn, Rn, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0195] E72. The process of E71 wherein the haloalcohol compound is a halohydrin compound of formula (III):wherein:X is a halogen; andRi, R2, R3, and R4are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

[0196] E73. The process of E71, wherein the haloalcohol compound is selected from the group consisting of 3-chloro-l-propanol, 3-bromo-l-propanol, l-bromo-2-propanol, 4-chloro-l-butanol, 4- bromo-l-butanol, 3-bromo-2-methyl-l-propanol, and 3-bromo-2,2-dimethyl-l-propanol.

[0197] E74. The process of E72, wherein the halohydrin compound is selected from the group consisting of 2-chloroethanol, 2-bromoethanol, and l-bromo-2-propanol.

[0198] E75. The process of E72, wherein the halohydrin compound is selected from the group consisting of 3-bromopropane-l,2-diol and 2-bromo-l,4-butanedioL

[0199] E76. The process of any of E63-E70, wherein the modified weak-base anion exchange resin comprises a modified amine group having the structure of formula (VII):wherein: n is an integer between 1 and 18; andR1, R2, Rn, Rn', R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the modified amine groups of formula (VII) are bound to the porous crosslinked copolymer backbone.

[0200] E77. The process of E72 wherein the halohydrin compound is a compound of formula (IV):wherein:X is a halogen; andRi, Rs, R3, and R« are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

Claims

What is claimed is:

1. A water insoluble modified weak-base anion exchange resin comprising a porous crosslinked polymeric backbone further comprising primary and / or secondary amine groups and wherein at least some of the amine hydrogen groups of the primary and / or secondary amine groups are further modified via a reaction with a haloalcohol or a halohydrin compound.

2. The water insoluble modified weak-base anion exchange resin of claim 1, wherein the porous crosslinked polymeric backbone is based on vinylic monomers crosslinked with divinylbenzene.

3. The water insoluble modified weak-base anion exchange resin of claim 2, wherein the vinylic monomers are selected from the group consisting of styrene, vinylamine, allyamine, acrylate, and methacrylate monomers.

4. The water insoluble modified weak-base anion exchange resin of claim 3, wherein the vinylic monomers are styrene.

5. The water insoluble modified weak-base anion exchange resin of claim 2, wherein the vinylic monomers are amine-containing vinyl monomers.

6. The water insoluble modified weak-base anion exchange resin of claim 5, wherein the amine- containing vinyl monomers are polyvinylamine or polyallylamine.

7. The water insoluble modified weak-base anion exchange resin of any of claims 1-6, wherein the haloalcohol compound is a compound of formula (I):whereinX is a halogen; n is an integer between 0 and 18; andR1, R2, Rn, Rn, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

8. The water insoluble modified weak-base anion exchange resin of claim 7, wherein the haloalcohol compound is a halohydrin compound of formula (III):whereinX is a halogen; andRi, R2, R3, and R« are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

9. The water insoluble modified weak-base anion exchange resin of claim 8, wherein the halohydrin compound is a compound of formula (IV):whereinX is a halogen; andRi, R2, R3, Rs, Re, and R7are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

10. The water insoluble modified weak-base anion exchange resin of claim 7, wherein the haloalcohol compound is selected from the group consisting of 3-chloro-l-propanol, 3-bromo-l- propanol, l-bromo-2-propanol, 4-chloro-l-butanol, 4-bromo-l-butanol, 3-bromo-2-methyl-l-propanol, 3-bromo-2,2-dimethyl-l-propanol, 4-bromo-l,2-butanediol and 6-bromo-l,2-hexanedioL11. The water insoluble modified weak-base anion exchange resin of claim 8, wherein the halohydrin compound is selected from the group consisting of 2-chloroethanol, 2-bromoethanol, 1- bromo-2-propanol, 3-bromopropane-l,2-diol and 2-bromo-l,4-butanediol.

12. A method for improving the oxidation stability of a weak-base anion exchange resin, the method comprising reacting a weak-base anion exchange resin with a haloalcohol compound or a halohydrin compound.

13. A water insoluble modified weak-base anion exchange resin comprising: a porous crosslinked copolymer backbone; one or more primary and / or secondary amine groups; and one or more modified amine groups, wherein at least one of the modified amine groups has the structure of formula (VII):wherein n is an integer between 1 and 18; andR1, R2, Rn, Rn', R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the one or more primary and / or secondary amine groups and the one or more modified amine groups are each bound to the porous crosslinked copolymer backbone.

14. The water insoluble modified weak-base anion exchange resin of claim 13, wherein the water insoluble modified weak-base anion exchange resin further comprises one or more additional modified amine groups, wherein at least one of the additional modified amine groups has the structure of formula (VIII):wherein n is an integer between 1 and 18; andR1, R2, Rn, Rn, R3, and R4are each, independently, selected from the group consisting ofhydrogen, hydrocarbyl, and substituted hydrocarbyl, and wherein the one or more additional modified amine groups are each bound to the porous crosslinked copolymer backbone.

15. The water insoluble modified weak-base anion exchange resin of claim 13 or claim 14, wherein the weak-base anion exchange resin comprises a porous crosslinked styrene-divinylbenzene copolymer backbone further comprising primary and / or secondary amine groups.

16. The water insoluble modified weak-base anion exchange resin of claim 13 or claim 14, wherein the water insoluble modified weak-base anion exchange resin further comprises crosslinked polymeric backbones based on amine-containing vinyl monomers crosslinked with divinylbenzene.

17. A process for capturing CO2from the atmosphere, the process comprising flowing a stream of ambient air over or through a sorbent, wherein the sorbent comprises a modified weak-base anion exchange resin comprising a porous crosslinked styrene-divinylbenzene copolymer backbone further comprising primary and / or secondary amine groups and wherein at least some of the amine hydrogen groups of the primary and / or secondary amine groups are further functionalized via a reaction with a haloalcohol compound.

18. The process of claim 17, wherein the haloalcohol compound is a compound of formula (I):whereinX is a halogen; n is an integer between 0 and 18; andR1, R2, Rn, Rn, R3, and R4are each, independently, selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

19. The process of claim 18, wherein the haloalcohol compound is a halohydrin compound of formula (III):whereinX is a halogen; andRi, R2, R3, and R« are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

20. The process of claim 19, wherein the halohydrin compound is a compound of formula (IV):whereinX is a halogen; andRi, 2, R3, Rs, Rs, and R7are each independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

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