Use of amine polymers in carbon capture

Abstract

Disclosed is the use of a nitrogen-containing polymer NP in CO2 capture, obtainable by reacting (i) a diamine or oligoamine A with (ii) a bridging compound BC, BC being (I) phosgene or (II) comprising at least two amine-reactive groups ARG, where BC is capable of bonding to the amine group of A to provide NP, where NP comprises BC bonded to at least two molecular components of A, and wherein the ratio of BC in the NP bonded to at least two A is a bridging factor BF wherein BF is greater than 50% wherein the sum of primary and secondary amine groups of the NP is at least 600 mg KOH / g and wherein the number average molecular weight of the NP is greater than 600 g / mol.

Description

Technical Field

[0001] This invention relates to the use of nitrogen-containing polymers (NPs) that can be optionally alkoxylated in the field of carbon capture, such as in direct air capture (DAC) applications, typically where carbon dioxide is directly absorbed from the air. Specifically, the amine-containing polymers are condensation products based on polyamines (such as tetraethylenepentamine (TEPA) and pentaethylenehexamine (PEHA)) with difunctional or polyfunctional bridging compounds (BCs) capable of linking the polyamine molecules together. The difunctional or polyfunctional bridging compounds (BCs) contain two or more amine reactive groups (ARGs). These amine-containing polymers can be optionally alkoxylated, for example by the action of one or more epoxides, to produce alkoxylated nitrogen-containing polymers (ANPs). Background Technology

[0002] The rising levels of greenhouse gases in the atmosphere are drawing increasing global attention due to their anticipated impacts on climate change. This is especially true given the rising levels of carbon dioxide. It is widely believed that even current atmospheric carbon dioxide concentrations are contributing to escalating environmental changes, including droughts, floods, and the destruction of global ecosystems. As carbon dioxide levels continue to rise, a significant increase in average atmospheric and ocean temperatures is projected, leading to accelerated melting of polar ice caps and glaciers, which in turn will result in rising sea levels and the inevitable inundation of low-lying areas. Increased atmospheric temperatures are also expected to increase the likelihood of severe global cyclones and storms.

[0003] Many national governments aim to take legislative action to reduce greenhouse gas emissions, particularly carbon dioxide, and ultimately limit global warming. Many countries have already adopted the Paris Agreement, a legally binding international climate change treaty. Its goal is to limit global warming to well below 2°C, preferably to 1.5°C, compared to pre-industrial levels.

[0004] In recent years, significant efforts have been made in developing technologies that can achieve the goal of reducing carbon dioxide levels in atmospheric air and / or gaseous emissions. Capturing carbon dioxide at its source is generally considered the most cost-effective approach. Typically, this source can be large-scale carbon-based energy facilities, natural gas processing, synthetic fuel plants, industries with predominantly carbon dioxide emissions (such as steelmaking and cement production), and hydrogen production plants using fossil fuels.

[0005] A major carbon capture technology involves the absorption or sequestration of carbon dioxide. To date, the most common active compounds used for carbon dioxide absorption rely on amine chemistry. Typical amines used for this purpose include alkanolamines (including monoethanolamine, diethanolamine, and diisopropanolamine), pentaethylenehexamine, tetraethylenepentamine, triethylenetetramine, tetraethylenetetramine, bis(2-hydroxypropyl)amine, N,N'-bis(2-hydroxyethyl)ethylenediamine, alkylamines, methylamine, linear polyethyleneimine, branched polyethyleneimine, dimethylamine, diethylamine, methyldiethanolamine, methylethanolamine, polyethylene polyamine, diethylenetriamine, and N,N'-bis-(3-aminopropyl)ethylenediamine.

[0006] U.S. Patent No. 9,084,960 B2 discloses a method for reducing the CO2 content in a gas and uses a CO2 scavenger that may include monoamines (particularly secondary amines such as diethanolamine), polyamines, monoguanides and polyguanides, and mixtures of these compounds.

[0007] U.S. Patent No. 9,533,250 B2 relates to reducing CO2 from indoor air in enclosed spaces. This reference describes amine-based compounds and proposes that such amine-based compounds may include any suitable amine (such as a primary or secondary amine as described below) or combinations thereof. This disclosure reveals that amine-based compounds can range from simple monomolecules (such as ethanolamine) to macromolecular amine polymers (such as polyethyleneimine). Monoethanolamine, ethanolamine, methylamine, branched polyethyleneimine, linear polyethyleneimine, diethanolamine, dimethylamine, diethylamine, diisopropanolamine, tetraethylenepentamine, methyldiethanolamine, methylethanolamine, and any of a number of polyamines (such as polyethyleneimine), or combinations thereof, are proposed in this document.

[0008] U.S. Patent No. 11,229,897 B2 discloses a gas-absorbing material comprising a polyamine produced using a method that does not use formaldehyde as a reaction product and / or reactant. The disclosure describes a reaction solution for producing a first amine compound and reactants. The reactants are said to contain carbonate or ketone compounds. The first amine compound reacts with the reactants to produce a second amine compound.

[0009] U.S. Patent No. 10,010,861 B2 and its corresponding publication US 2018 / 0008958 A1 describe a polymeric amine in the context of carbon dioxide absorption. The polymeric amine is said to consist of a polymeric backbone containing nitrogen atoms and branched chains bonded to the nitrogen atoms of the polymeric backbone. Each branched chain contains at least one nitrogen atom, and the polymeric amine is modified by replacing a nitrogen atom in the polymeric backbone or at least one nitrogen atom in the branched chain with a hydroxyl-containing carbon chain. Example 1 describes the synthesis of a polyethyleneimine modified by partial substitution with butane. This synthesis involves dissolving polyethyleneimine (MN = 1200, 19 mmol N / g) in methanol. This disclosure reveals the addition of butane to the polyethyleneimine / methanol solution in different amounts such that the molar ratio of butane to nitrogen atoms present in the polyethyleneimine is 0.15:1, 0.37:1, and 0.54:1. This disclosure reveals a method for removing solvents by subjecting a solution of modified poly(ethylene imide) to heating in a vacuum oven.

[0010] US Patent No. 10,751,689 B2 and its corresponding publication US 2016 / 0199810 A1 disclose modified polyamines in the context of carbon dioxide absorption. The modified polyamine is a reaction product of an amine and an epoxide. The described amines are relatively low molecular weight amines, such as pentaethylenehexamine (PEHA) and tetraethylenepentamine (TEPA), and such amines are referred to as oligoamines. Example 1 discloses the preparation of a modified polyamine based on pentaethylenehexamine (PEHA) and propylene oxide (PO). The preparation describes dissolving 10 g of PEHA in 40 mL of water and adding 5 g of PO to the PEHA solution, followed by stirring at room temperature for 20 hours. The temperature of the reaction mixture is said to be gradually increased to 60ºC and maintained for two hours. Water is said to be removed by a rotary evaporator, followed by overnight incubation under vacuum below 1 mmHg.

[0011] U.S. Patent Application Publication No. 2019 / 0076820 A1 describes a method and apparatus for removing volatile components from a mixture, wherein the method and apparatus use a crosslinked elastomer with a glass transition temperature ≤ +25°C as an adsorbent. This disclosure describes alternatives in paragraph

[0029] as an example, wherein the VOC can be an organic monomer used in the polymerization or crosslinking, such as ethylene, propylene, and various other hydrophobic vinyl addition monomers, and furthermore, this list includes glycidyl methacrylate, phosgene, isocyanates, amine compounds such as ethylenediamine, and epoxy compounds such as oligomeric liquid epoxy resins. It is also said that the VOC can be a petroleum-derived fuel or fuel mixture such as diesel fuel, or alternatively, the VOC can be a toxic or aging-causing organic compound such as an organosulfur compound. Alternatively, it is said that the VOC can be CO2.

[0012] International Application Publication No. WO 2021 / 168498 A1 describes a method for removing CO2 from a gaseous stream with a low carbon dioxide (CO2) concentration. The method reportedly involves contacting the gaseous stream with a hydrogel to absorb at least some CO2 from the gaseous stream. The hydrogel reportedly comprises a cross-linked hydrophilic polymer, including hydrophilic polymers cross-linked with a cross-linking agent. Example 1 describes the fabrication of polyethylene imide (PEI) hydrogel particles cross-linked by adding a cross-linking solution of 1,3-butadiene diethoxide at different concentrations. Example 5 describes direct air capture (DAC) using PEI hydrogels and evaluates their DAC capability.

[0013] U.S. Patent Application Publication No. 2022 / 0347654 A1 describes a method for generating CHEFS (chemisorbent fiber adsorbent) from a stock solution. One or more embodiments relate to a method for generating CHEFS having amine functional groups, the method comprising the steps of: generating a stock solution containing a BIAS (basic immobilized amine adsorbent) having amine groups, at least one polymer, and at least one solvent; and forming CHEFS from the stock solution. CHEFS is said to be suitable for capturing CO2. This disclosure describes a BIAS in paragraph

[0036] , which generally comprises about 60 wt% silica and 40 wt% of a combination of polyamines and crosslinking agents, wherein the crosslinking agents include epoxy silanes, polyepoxides, aminosilanes, and acrylamide-based crosslinking agents, and combinations thereof. The reference describes an exemplary BIAS comprising silica particles with an average particle size of 25 µm, and polyethyleneimine (wherein the polyethyleneimine is a crosslinked polyethyleneimine Mw = 800) and N,N-diglycidyl-4-glycidoxyaniline.

[0014] Polyethylene imide (PEI) and other polyalkylimides (such as polypropylene imide (PPI)) are known for their stability as CO2 adsorbents in DACs and their excellent performance in post-combustion processes and CO2 capture from point sources. These sources are typically found in three areas: fuel combustion activities, industrial processes, and natural gas processing.

[0015] Linear PEI and linear PPI are known to be superior to branched PEI and branched PPI, and this is thought to be due to the relatively higher secondary amine content in the linear products compared to their branched counterparts. Low fractions of primary NH functional groups are known to be more beneficial for CO2 absorption. This can be improved by alkoxylation of PEI or PPI, but such improvement is often limited.

[0016] Lower molecular weight polyamines such as tetraethylenepentamine (TEPA) and pentaethylenehexamine (PEHA) are also known as good CO2 adsorbents. The use of these polyamines for CO2 capture has been proposed in patents and literature for various carbon capture applications, such as DAC. However, these low molecular weight polyamines suffer from the disadvantage of exhibiting higher vapor pressures, which can be particularly problematic for the recycling of the adsorbent at high temperatures, typically in the CO2 desorption step, where higher polyamine loss is observed.

[0017] The object of this invention is to develop nitrogen-based products that exhibit good or improved CO2 absorption capacity, and the inventors particularly intend to provide such products that exhibit a more favorable ratio of secondary NH functional groups to primary NH functional groups. Another particular object is to develop such products that can typically be more easily recycled during CO2 desorption steps involving high temperatures. Summary of the Invention

[0018] This invention provides the use of optionally alkoxylated nitrogen-containing polymers in carbon dioxide capture, which can be obtained by a method comprising the following steps:

[0019] a) React (i) a diamine or oligoamine (A) with (ii) a bridging compound (BC),

[0020] Bridging compounds (BC)

[0021] (I) is phosgene; or

[0022] (II) Contains at least two amine reactive groups (ARG),

[0023] The bridging compound (BC) can bond to the amine groups of at least two diamine or oligoamine (A) molecules.

[0024] To provide nitrogen-containing polymers (NP),

[0025] The nitrogen-containing polymer (NP) comprises a bridging compound (BC) molecular component bonded to at least two molecular components of a diamine or oligoamine (A), and the proportion of bridging compound (BC) molecules bonded to at least two molecules of diamine or oligoamine (A) is the bridging factor (BF) of the nitrogen-containing polymer (NP), wherein the bridging factor (BF) is greater than 50%.

[0026] The total amount of primary and secondary amine groups in the nitrogen-containing polymer (NP) is at least 600 mg KOH / g.

[0027] Furthermore, the number-average molecular weight (Mn) of the nitrogen-containing polymer (NP) is greater than 600 g / mol, and

[0028] b) Optionally, the nitrogen-containing polymer (NP) is reacted with an alkylene oxide (AO), preferably selected from the group consisting of at least one of ethylene oxide (EO), propylene oxide (PO), and butane oxide (BuO), wherein the molar ratio of the alkylene oxide (AO) to the NH functional group of the nitrogen-containing polymer (NP) is not greater than 0.25.

[0029] In order to obtain an alkylene oxide side chain (AB) attached to a nitrogen atom of a nitrogen-containing polymer (NP), thereby providing an alkoxylated nitrogen-containing polymer (ANP).

[0030] The present invention also includes a method for capturing carbon dioxide, the method comprising contacting a gas mixture containing carbon dioxide with an optionally alkoxylated nitrogen-containing polymer, the optionally alkoxylated nitrogen-containing polymer being obtained by a method comprising the following steps:

[0031] a) React (i) a diamine or oligoamine (A) with (ii) a bridging compound (BC),

[0032] Bridging compounds (BC)

[0033] (I) is phosgene; or

[0034] (II) Contains at least two amine reactive groups (ARG),

[0035] The bridging compound (BC) can bond to the amine groups of at least two diamine or oligoamine (A) molecules.

[0036] To provide nitrogen-containing polymers (NP),

[0037] The nitrogen-containing polymer (NP) comprises a bridging compound (BC) molecular component bonded to at least two molecular components of a diamine or oligoamine (A), and the proportion of bridging compound (BC) molecules bonded to at least two molecules of diamine or oligoamine (A) is the bridging factor (BF) of the nitrogen-containing polymer (NP), wherein the bridging factor (BF) is greater than 50%.

[0038] The total amount of primary and secondary amine groups in the nitrogen-containing polymer (NP) is at least 600 mg KOH / g.

[0039] Furthermore, the number-average molecular weight (Mn) of the nitrogen-containing polymer (NP) is greater than 600 g / mol, and

[0040] b) Optionally, the nitrogen-containing polymer (NP) is reacted with an alkylene oxide (AO), preferably selected from the group consisting of at least one of ethylene oxide (EO), propylene oxide (PO), and butane oxide (BuO), wherein the molar ratio of the alkylene oxide (AO) to the NH functional group of the nitrogen-containing polymer (NP) is not greater than 0.25, in order to obtain an alkylene oxide side chain (AB) attached to the nitrogen atom of the nitrogen-containing polymer (NP), thereby providing an alkoxylated nitrogen-containing polymer (ANP).

[0041] The optional alkoxylated nitrogen-containing polymer (NP) is contacted with carbon dioxide. Detailed Implementation

[0042] A bridging compound (BC) is a compound that is to be bonded to at least two amine groups (i.e., amine groups of at least two different diamine or oligoamine (A) molecules) to form a bridge in order to construct the structure of a nitrogen-containing polymer (NP). Such a bridging compound (BC) is phosgene or a compound containing at least two amine reactive groups (ARGs) and is capable of bonding to at least two amine groups to link at least two molecules of diamine or oligoamine (A) together.

[0043] Phosgene will react with the primary amine group of the diamine or oligoamine (A) to form an isocyanate group, which will further react with the amine group of another molecule of the diamine or oligoamine, thereby forming a bridge between the molecules of the diamine or oligoamine.

[0044] Preferably, the bridging compound (BC) contains at least two amine reactive groups (ARG) and is capable of bonding with at least two amine groups of a diamine or oligoamine.

[0045] The bridging compound (BC) is preferably a reaction product formed by reacting (i) a diol or polyol with (ii) an epichlorohydrin, preferably an epichlorohydrin.

[0046] Diols or polyols are organic compounds containing two or more hydroxyl groups. This includes diols, triols, or compounds having four or more hydroxyl groups.

[0047] Suitable examples of diols include aliphatic compounds containing 2 to 14 carbon atoms. Specific examples include ethane-1,2-diol (ethylene glycol), propane-1,2-diol (propylene glycol), propane-1,3-diol (trimethylene glycol), butane-1,2-diol, butane-1,3-diol, butane-1,4-diol, pentane-1,2-diol, pentane-1,3-diol, pentane-1,4-diol, pentane-1,5-diol, cyclopentane-1,2-diol, 4-methylcyclopentane-1,3-diol, cyclohexane-1,2-diol, cyclohexane-1,3-diol, cyclohexane-1,4-diol, and 2-ethylhexane-1,3-diol. Preferred diols are ethane-1,2-diol (ethylene glycol), propane-1,2-diol (propylene glycol), and propane-1,3-diol (trimethylene glycol). Examples of triols include propane-1,2,3-triol (glycerol), butane-1,2,3-triol, butane-1,2,4-triol, pentane-1,2,3-triol, pentane-1,2,4-triol, pentane-1,2,5-triol, and pentane-1,3,5-triol. Propane-1,2,3-triol (glycerol) is preferred. Other polyols include pentaerythritol.

[0048] Suitable polyols include sugar alcohols, which are typically derived from sugars. They are characterized by a hydroxyl group attached to each carbon atom. Examples of sugar alcohols include erythritol, xylitol, sorbitol, mannitol, threitol, arabinitol, ribitol, galactitol, fucitol, idotitol, inositol, and volemitol.

[0049] Other polyols may include polyethers or polyester polyols carrying at least two hydroxyl groups (typically as terminal groups). Polyethers typically contain repeating alkylene oxide units with hydroxyl groups as terminal groups. Polyester polyols typically contain repeating alkylene ester bonds but have terminal hydroxyl groups. Preferably, the number of repeating units in both the polyether and the polyester polyol will not exceed six, for example, 2 to 6, preferably 2 to 3. Preferred polyethers as polyols include diethylene glycol and triethylene glycol.

[0050] Preferably, the diol or polyol is selected from the group consisting of: 1,4-butanediol, 1,6-hexanediol, 1,3-neopentylenediol, 1,4-cyclohexanediol, glycerol, and trimethylolpropane.

[0051] Epichlorohydrin is typically epichlorohydrin. Epichlorohydrin is also known as (chloromethyl)ethylene oxide, 1-chloro-2,3-epoxypropane, γ-chloroepoxypropane, glycidyl chloride, or ECH.

[0052] The reaction product of (i) a diol or polyol with (ii) an epichlorohydrin, preferably an epichlorohydrin, will contain glycidyl groups and will typically be bonded to the diol or polyol group via ether bonding instead of hydroxyl groups. Such reaction products containing at least two glycidyl groups will be effective bridging compounds (BCs).

[0053] Preferably, the reaction product of (i) a diol or polyol with (ii) an epichlorohydrin, preferably epichlorohydrin, will be a reaction product containing at least 55 mol%, suitably greater than 60 mol%, preferably greater than 70 mol%, and even more preferably greater than 80 mol% of reaction product molecules containing two epoxy groups. In a more preferred embodiment, the reaction product is formed by reacting a mixture of (i) a diol and a triol with (ii) an epichlorohydrin, preferably epichlorohydrin, and wherein the reaction product contains more than 90 mol% of reaction product molecules containing two epoxy groups. Depending on the purity of the diol or polyol, the reaction product may contain up to 45 mol% of one epoxy group, suitably less than 40 mol%, preferably less than 30 mol%, and more preferably less than 20 mol%. Particularly preferably, less than 10 mol% of the reaction product molecules contain one epoxy group, such as less than 5 mol%, typically less than 1 mol%, for example less than 0.5 mol%, for example less than 0.1 mol%. Reaction products containing three or more epoxy groups can also be used as bridging compounds (BCs) for reactions with diamines or oligoamines. Suitably, the reaction products may comprise mixtures containing molecules primarily having two epoxy groups, molecules containing three or more epoxy groups, and molecules containing one epoxy group. Desiredly, such reaction products may contain up to 40 mol% of molecules containing three or more epoxy groups, more preferably up to 30 mol% of molecules containing three or more epoxy groups. Furthermore, it is particularly preferred that less than 20 mol% and especially preferably less than 10 mol% of the reaction product molecules contain three or more epoxy groups.

[0054] The bridging compound (BC) is preferably a compound containing at least two amine reactive groups (ARGs). The amine reactive groups (ARGs) in this invention can be any group reactive to an amine group. Typically, such amine reactive groups (ARGs) will include functional groups such as epoxides, isocyanates, terminal isocyanates, esters, and acid anhydrides.

[0055] In a preferred form, the bridging compound (BC) comprises at least two epoxy groups. These at least two epoxy groups, as amine reactive groups (ARGs), readily react with the amine groups, preferably primary amine groups, of the diamine or oligoamine (A) to form amino alcohol bonds between the diamine or oligoamine (A). Suitably, the two epoxy groups can be part of an aliphatic molecule, such as 1,2,3,4-diepoxybutane, 1,2,4,5-diepoxypentane, 1,2,5,6-diepoxyhexane, and 1,2,7,8-diepoxyoctane. More preferably, each epoxide is part of a glycidyl group, and even more preferably, at least two glycidyl groups are glycidyl ether groups. Suitable examples of bridging compounds (BCs) containing at least two glycidyl ether groups include diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, neopentyl diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, and 5,5-dimethyl-3,7-dioxa-1,9(2)-bis(oxirana)-4,6(2,4)-dibenzenanonaphane.

[0056] Another suitable group of bridging compounds (BCs) are diisocyanates, wherein the amine reactive group (ARG) consists of two isocyanate groups. Isocyanates readily react with amine groups to obtain urea derivatives. Therefore, the two isocyanate groups of a diisocyanate can readily react with the amine, preferably primary amine, groups of two diamine or oligoamine (A) molecules and link them together via urea bonding. Examples of suitable diisocyanates include methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), methylene dicyclohexyl diisocyanate or hydrogenated MDI (HMDI), and isophorone (IPDI).

[0057] It may be desirable to use capped diisocyanates to control the reaction between the isocyanate group and the amine group of the diamine or oligoamine (A). This allows the reaction to occur after a specific trigger, such as at a specific temperature or upon exposure to UV light. Examples of capping agents used with diisocyanates to cap them include methyl ethyl ketone oxime. Typically, the use of capped diisocyanates may not be necessary.

[0058] Another suitable group of bridging compounds (BCs) are diesters. Suitable examples include carbonates, which can be reacted with the amine groups of two diamine or oligoamine (A) molecules via ammonolysis to form a urea bridging the diamine or oligoamine (A) moiety. Further suitable examples include terephthalates, which will also react with the amine groups of two diamine or oligoamine (A) molecules to form a terephthalamide bridge between the diamine or oligoamine molecules.

[0059] Bridging compounds (BCs) may contain at least two anhydride groups as amine reactive groups (ARGs). The anhydride groups are reactive to amines and form amide bonds when reacting with amines.

[0060] Preferably, the bridging compound (BC) is a compound containing at least two amine reactive groups (ARGs), selected from the group consisting of compounds containing at least two glycidyl ether groups and at least two diisocyanate groups. More preferably, the bridging compound (BC) is a compound containing at least two glycidyl ether groups.

[0061] More preferably, the bridging compound (BC) is a compound containing at least two glycidyl ether groups, and is such a compound as:

[0062] (i) Contains at least twice the structure according to formula (I)

[0063] (I)

[0064] The dashed lines indicate bonds to the remainder of compounds containing at least two glycidyl ether groups, preferably compounds containing at least two glycidyl ether groups having twice the structure according to formula (I); and / or

[0065] (ii) Select from the group consisting of: 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, diglycidyl ether, 1,3-neopentyl glycol diglycidyl ether, 1,4-cyclohexanediethanol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol triglycidyl ether and trimethylolpropane triglycidyl ether.

[0066] The bridging compound (BC) should contain at least two amine reactive groups (ARG) in order to satisfactorily form molecular bridges between diamine or oligoamine molecules (A).

[0067] A bridging compound (BC) can comprise a mixture of bridging compound (BC) molecules containing at least two amine reactive groups (ARGs) and molecules containing only one amine reactive group (ARG). Typically, the amine reactive groups (ARGs) of the bridging compound (BC) molecules contained in such a mixture should be the same, of the same class, or at least not react with each other. Typically, these amine reactive groups (ARGs) are identical to each other. Suitablely, a bridging compound (BC) comprises a dominant bridging compound (BC) molecule containing at least two amine reactive groups (ARGs). In some cases, a bridging compound (BC) can comprise up to 45 mol% of a monofunctional molecule, i.e., containing only one amine reactive group (ARG). This may depend on the purity of the bridging compound. For example, a diglycidyl ether can comprise up to 45 mol% of a monofunctional compound containing only one epoxy group and at least 55 mol% of diglycidyl ether molecules containing two epoxy groups.

[0068] Preferably, the bridging compound (BC) mainly comprises bridging compound (BC) molecules containing two amine reactive groups (ARGs), preferably both of which are epoxy groups. Suitably, the bridging compound (BC) comprises more than 60 mol% of a compound having two amine reactive groups (ARGs) (preferably both of which are epoxy groups) and more preferably less than 40 mol% of a compound having one amine reactive group (ARG), preferably an epoxy group; and more preferably more than 70 mol% of a compound having two amine reactive groups (ARGs) (preferably both of which are epoxy groups) and more preferably less than 30 mol% of a compound having one amine reactive group (ARG), preferably an epoxy group; and more preferably more than 80 mol% of a compound having two amine reactive groups (ARGs) (preferably both of which are epoxy groups) and more preferably less than 20 mol% of a compound having one amine reactive group (ARG), preferably an epoxy group. Particularly preferably, less than 10 mol% of the bridging compound (BC) molecules should contain only one amine reactive group (ARG), preferably an epoxy group. Particularly preferred is that the bridging compound (BC) substantially does not contain molecules containing only one amine reactive group (ARG).

[0069] Therefore, it is possible that a relatively small proportion of compounds containing only one amine reactive group (ARG) may be present alongside the bridging compound (BC). However, this should preferably be kept to a minimum, as higher levels of such compounds containing only one amine reactive group (ARG) may be detrimental to the construction of the molecular structure of the nitrogen-containing polymer (NP). Typically, the amount of compounds containing only one amine reactive group (ARG) should be less than 10 mol%, typically less than 5 mol%, typically less than 1 mol%, preferably less than 0.5 mol%, more preferably less than 0.1 mol%. Particularly preferably, the bridging compound (BC) should be substantially free of or contain no compounds containing only one amine reactive group (ARG).

[0070] Bridging compounds (BCs) containing three or more amine reactive groups (ARGs), preferably epoxy groups, can also be used to react with diamines or oligoamines (A). Suitably, the bridging compound (BC) can comprise a mixture of bridging compound (BC) molecules that primarily consist of molecules having two amine reactive groups (ARGs) and the remainder consists of molecules containing three or more amine reactive groups (ARGs) and / or molecules containing one amine reactive group (ARG). In a preferred form, the mixture should consist primarily of bridging compound (BC) molecules having two epoxy groups and the remainder consists of molecules containing three or more epoxy groups and / or molecules containing one epoxy group.

[0071] Particularly preferred, less than 20%, and especially preferred, less than 10%, of the bridging compound (BC) molecules have three or more amine reactive groups (ARGs). This is to avoid undesirable crosslinking levels of the nitrogen-containing polymer (NP), which could adversely affect the polymer's solubility in water.

[0072] Crosslinking of nitrogen-containing polymers (NPs) is acceptable, provided that the solubility of the NPs in water is not adversely affected. Generally, crosslinking is tolerable because it can even reduce the volatility of the NPs to offset any minor impact on water solubility. The degree of crosslinking can be controlled by adjusting the ratio of reaction product molecules containing two epoxy groups to those containing three or more epoxy groups to those containing only one epoxy group.

[0073] The diamine or oligoamine (A) preferably contains at least 2 amino groups and more preferably 2 to 12 amino groups. Preferably, the diamine or oligoamine (A) contains 2 to 8 amino groups, such as 3, 4, 5, 6, 7 or 8 amino groups, more preferably 4 to 8 amino groups.

[0074] Typically, the diamine or oligoamine (A) has at least one carbon atom per nitrogen atom, preferably one to five carbon atoms per nitrogen atom, and more preferably one to three carbon atoms per nitrogen atom. Typically, the nitrogen atoms are separated from each other by two to six carbon atoms of at least one saturated hydrocarbon group (e.g., alkylene or alkyltriyl, preferably an alkylene group having two to four carbon atoms).

[0075] Desiredly, the diamine or oligoamine (A) has at least two primary amino groups and / or secondary amino groups. Preferably, the diamine or oligoamine (A) has at least two primary amino groups, and more preferably, the secondary amino groups predominate over the primary amino groups.

[0076] The weight-average molecular weight (M) of diamines or oligoamines (A) W Suitablely within the range of 50 to 500 g / mol, preferably 60 to 300 g / mol, more preferably 80 to 250 g / mol, even more preferably 120 to 250 g / mol, and especially preferably 150 to 250 g / mol.

[0077] Preferably, the at least one diamine or oligoamine (A)

[0078] (i) having at least 2 amino groups, suitably 2 to 12 amino groups, preferably 2 to 8 amino groups, more preferably 3, 4, 5, 6, 7 or 8 amino groups; and

[0079] (ii) having at least one carbon atom per nitrogen atom, preferably 1 to 5 carbon atoms per nitrogen atom, more preferably 1 to 3 carbon atoms per nitrogen atom; and

[0080] (iii) Contains at least two primary amino groups and / or secondary amino groups, preferably at least two primary amino groups; and

[0081] (iv) Having a molecular weight (Mw) in the range of 50 to 500 g / mol, preferably in the range of 60 to 300 g / mol, more preferably in the range of 80 to 250 g / mol, even more preferably in the range of 120 to 250 g / mol, and especially preferably in the range of 150 to 250 g / mol.

[0082] Independent of or other than the features (i), (ii), (iii) and (iv) above, the diamine or oligoamine (A) is preferably selected from the group consisting of: ethylenediamine, hexamethylenediamine, methylcyclohexanediamine (MCDA), propylenediamine (PDA), tetramethylenediamine (TMDA), pentamethylenediamine (PMDA), dipropylenetriamine (DPTA), tripropylenetetramine (TPTA), tri(2-aminoethyl)amine (TAEA), tetrapropylenepentamine (TPPA), N,N'-bis-(3-aminopropyl)-ethylenediamine (N4-amine), 3-(2-aminoethylamino)propylamine (N3-amine), spermine, spermidine, triaminononane, diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), pentaethylenehexamine (PEHA), and compounds according to formulas (II) to (X).

[0083] (II) (III)

[0084] (IV)

[0085] (V) (VI)

[0086] (VII) (VIII)

[0087] (IX)

[0088] (X).

[0089] In some cases, it may be desirable for the diamine or oligoamine (A) to contain a certain degree of alkoxylation. This alkoxylated diamine or oligoamine (A) then reacts with the bridging compound (BC) in step (a). Typically, the degree of alkoxylation should be only partial so as not to prevent or adversely affect the reaction of the diamine or oligoamine (A) with the bridging compound (BC) in step (a). For example, the molar ratio of the alkylene oxide (AO) to the NH functional group of the diamine or oligoamine (A) does not exceed 0.25, suitably 0.05 to 0.25, and more suitably 0.05 to 0.20. Preferably, the diamine or oligoamine (A) is substantially unalkoxylated, for example, the molar ratio of the alkylene oxide (AO) to the NH functional group of the diamine or oligoamine (A) is less than 0.05, for example less than 0.01, and especially less than 0.001. Most preferably, the diamine or oligoamine (A) does not contain alkoxylation.

[0090] Desiredly, the molar ratio of the bridging compound (BC) to the diamine or oligoamine (A) can be in the range of 0.35 to 0.85, preferably 0.4 to 0.8, more preferably 0.45 to 0.75, and particularly 0.5 to 0.7.

[0091] It is particularly desirable that the molar ratio of the epoxy group of the bridging compound (BC) used to form the optionally alkoxylated nitrogen-containing polymer (NP) to the NH functional group of the diamine or oligoamine (A) is less than 0.5, preferably up to 0.45, more preferably up to 0.4, for example 0.1 to 0.45, desirablely 0.15 to 0.4 and even more desirablely 0.15 to 0.3.

[0092] The NH functional group represents the amine value and is calculated by determining the secondary and primary amine groups, where NH = (number of secondary amine groups) + (2 x (number of primary amine groups)). NH is determined by titrating the corresponding polyalkylene imide with trifluoromethanesulfonic acid.

[0093] In one embodiment of the optionally alkoxylated nitrogen-containing polymer (NP), the proportion of the diamine or oligoamine molecular component having fewer than two amine groups bonded to the bridging compound (BC) molecular component is less than 25%.

[0094] However, preferably, the alkoxylated nitrogen-containing polymer (NP) optionally contains at least 20%, suitably 25% to 90%, desirablely 30% to 85%, more desirablely 35% to 80%, typically 40% to 80%, generally 45% to 75%, and preferably 50% to 75% of a diamine or oligoamine molecular component having fewer than two amine groups bonded to the bridging compound (BC) molecular component.

[0095] Alkoxylated nitrogen-containing polymers (NPs) can be optionally prepared by reacting a diamine or oligoamine compound with a bridging compound (BC) under other suitable reaction conditions to form the nitrogen-containing polymer (NP). When preparing alkoxylated nitrogen-containing polymers (NPs), the nitrogen-containing polymer (NP) can be alkoxylated with a suitable alkoxylating agent, typically an epoxide.

[0096] Suitablely, nitrogen-containing polymers (NPs) can be prepared by combining a diamine or oligoamine compound with a bridging compound (BC) in a suitable container. The reaction can be carried out anhydrous or in the presence of a suitable solvent. When a solvent is used, it can be aqueous, but preferably it is an organic solvent, more preferably a polar organic solvent, such as methanol, ethanol, isopropanol, acetone, DMF, or chloroform, and even more preferably methanol. For such reactions in which the reaction products will accumulate greater viscosity, the use of a solvent may be desirable. When using a higher ratio of the bridging compound to the diamine or oligoamine (amine compound), for example at least 1.3 equivalents of the bridging compound to 2 equivalents of the amine compound, the use of a solvent, particularly a polar organic solvent, most preferably methanol, may be desirable. The reaction can be carried out at any suitable temperature. Suitablely, the temperature can be above 25°C, typically at least 30°C, for example from 30°C to 90°C, and preferably from 35°C to 85°C. When the reaction is carried out in the presence of a solvent, preferably methanol, the reaction temperature can be, for example, 30°C to 45°C, typically 30°C to 40°C. When the reaction is carried out in the absence of a solvent (i.e., anhydrous), the reaction temperature can be 35°C to 90°C, for example 45°C to 85°C, preferably 50°C to 85°C, for example 60°C to 85°C, preferably 70°C to 85°C, more preferably 75°C to 85°C. The reaction time can depend on the mass of the reactants, the presence or absence of a solvent, and the reaction temperature. Typically, the reaction can be completed within a time period of 1 hour to 3 hours, for example 1.5 to 2.5 hours. In the case where a solvent, particularly an organic solvent (such as methanol), has been used, the solvent is typically removed from the nitrogen-containing polymer (NP) thus formed at the end of the reaction. This can be achieved by using high temperature and / or reduced pressure. Typically, this can be achieved using temperatures greater than 60°C, for example 75°C to 95°C. When using depressurization, the depressurization can be below 1.0 bar, for example below 500 mbar, typically below 250 mbar.

[0097] The nitrogen-containing polymer (NP) used in this invention is typically a liquid at 25°C.

[0098] Nitrogen-containing polymers (NPs) can be alkoxylated as described herein.

[0099] The uses according to the invention include those of nitrogen-containing polymers (NPs) (i.e., unalkoxylated polymers).

[0100] In a preferred embodiment, the alkoxylated nitrogen-containing polymer is optionally an alkoxylated nitrogen-containing polymer (ANP). Alkoxylation of the nitrogen-containing polymer (NP) is typically achieved by reacting the nitrogen-containing polymer (NP) with an epoxide. Preferably, the alkoxylation method is carried out in an aqueous medium. The epoxide (AO) reacts with the NH group of the nitrogen-containing polymer (NP) to provide an alkoxylated substituent bonded to the nitrogen atom. Alternatively, the alkoxylated nitrogen-containing polymer can be derived from a reaction of a diamine or oligoamine (A) that has been alkoxylated prior to reaction with the bridging compound (BC). Pre-alkoxylation of the diamine or oligoamine (A) eliminates any requirement for post-alkoxylation of the nitrogen-containing polymer. In some cases, it may be desirable to further alkoxylate the nitrogen-containing polymer derived from the pre-alkoxylated diamine or oligoamine (A). Preferably, in cases where alkoxylation of the nitrogen-containing polymer (NP) is desired, the alkoxylation step (b) should be performed after the formation of the nitrogen-containing polymer (NP) in step (a).

[0101] Ideally, the molar ratio of alkyl oxidase (AO) to the NH functional group of the nitrogen-containing polymer (NP) is up to 0.25, preferably from 0.05 to 0.25, more preferably from 0.05 to 0.2, more preferably from 0.05 to 0.15, for example from 0.075 to 0.125.

[0102] As described above, NH represents the amine value and is calculated by determining the secondary and primary amine groups, where NH = (number of secondary amine groups) + (2 x (number of primary amine groups)). NH is determined by titrating the corresponding polyalkylene imide with trifluoromethanesulfonic acid.

[0103] In a typical representation, alkoxylated nitrogen-containing polymers (ANPs) contain structural elements according to formula (XI).

[0104] (XI)

[0105] in,

[0106] The dashed lines indicate the bonds with the remaining portion of the alkoxylated nitrogen-containing polymer; and

[0107] AB represents an alkylene oxide side chain.

[0108] The epoxide (AO) can be any suitable epoxide used for the alkoxylation of nitrogen-containing polymers (NPs). In a desired embodiment, the epoxide can be one or a mixture of more than one of the following: C2-C 12 -Epoxide, preferably C2-C 10- Epoxides, more preferably C2-C8-epoxides, preferably ethylene oxide, propylene oxide, or butane oxide, more preferably propylene oxide or butane oxide. In a desired embodiment, the epoxide (AO) is a mixture of epoxides comprising C2-C4 epoxides and C8-C4 epoxides. 12 Mixtures of epoxides, preferably having a ratio of 2:1 to 20:1, more preferably 5:1 to 10:1, of C2-C4 epoxides to C8-C4 epoxides. 12 The molar ratio. However, most preferably, the alkyl oxidant (AO) is essentially only one alkyl oxidant, for example, only one alkyl oxidant with a weight of more than 90%, preferably more than 95%, and more preferably more than 99%.

[0109] Optional alkoxylated nitrogen-containing polymers typically have a higher weight-average molecular weight (M) than diamines or oligoamines (A). W At least 70% greater than the weight-average molecular weight (M). W Typically, the weight-average molecular weight (M) of nitrogen-containing polymers can be optionally alkoxylated. W It is at least 150% larger than the diamine or oligoamine (A), preferably at least 300%.

[0110] Desiredly, the number average molecular weight (Mn) of the alkoxylated nitrogen-containing polymer may optionally be in the range of 600 to 50,000 g / mol, for example 600 to 20,000 g / mol, preferably 600 to 10,000 g / mol, more preferably 800 to 5,000 g / mol, more preferably 600 to 2,500 g / mol, and even more preferably 1,000 to 2,500 g / mol.

[0111] In a preferred embodiment, the fraction of optionally alkoxylated nitrogen-containing polymers with a molecular weight greater than 15,000 g / mol is less than 10%, and more preferably, the fraction of polymers with a molecular weight greater than 10,000 g / mol is less than 10%.

[0112] The polydispersity index (Mw / Mn) of unalkoxylated nitrogen-containing polymers (including nitrogen-containing polymers (NPs) prior to any alkoxylation) can be in the range of up to 7, suitably 2 to 7, for example 3 to 7.

[0113] The ratio of secondary to primary amines in unalkoxylated or unalkoxylated nitrogen-containing polymers can be 1.3:1 to 2.2:1, for example 1.4:1 to 2.1:1.

[0114] The sum of primary and secondary amine groups in unalkoxylated nitrogen-containing polymers (NPs), including unalkoxylated polymers, is at least 600 mg KOH / g. For example, this could be at least 603 mg KOH / g.

[0115] The NH functional group of the unalkoxylated nitrogen-containing polymer (NP) (including unalkoxylated polymers) is at least 800 mg KOH / g. For example, this could be at least 804 mg KOH / g.

[0116] The OH value of unalkoxylated nitrogen-containing polymers (NPs) (including unalkoxylated polymers) can be 160 to 260 mg KOH / g, for example 170 to 250 mg KOH / g.

[0117] Optional alkoxylated nitrogen-containing polymers (NPs) should be liquid at 25°C.

[0118] Preferably, the optionally alkoxylated nitrogen-containing polymer is soluble in water. Soluble in water means that the optionally alkoxylated nitrogen-containing polymer will dissolve or miscible with a concentration of up to 350 g / L of deionized water at a temperature of 25°C. The polymer is considered soluble in water if the aqueous solution of the optionally alkoxylated nitrogen-containing polymer preferably remains clear without any observed opacity or phase separation after storage, for example, after storage for at least seven days.

[0119] Optionally, the alkoxylated nitrogen-containing polymer can be linear or branched. In a preferred embodiment, the alkoxylated nitrogen-containing polymer is branched. In this preferred embodiment, the branched alkoxylated nitrogen-containing polymer is preferably soluble in water. In another preferred embodiment, the alkoxylated nitrogen-containing polymer is linear. In this preferred embodiment, the linear alkoxylated nitrogen-containing polymer is water-soluble.

[0120] In a suitable embodiment, the alkoxylated nitrogen-containing polymer is optionally substantially unquaternized, for example, wherein less than 10%, preferably less than 5%, more preferably less than 1%, particularly preferably less than 0.5%, and even more particularly preferably less than 0.1% of nitrogen atoms present in the optionally alkoxylated nitrogen-containing polymer are quaternized. In this embodiment, particularly preferably, the optionally alkoxylated nitrogen-containing polymer is not quaternized.

[0121] In a preferred embodiment, the alkoxylated nitrogen-containing polymer is optionally alkoxylated, and the molar ratio of the alkylene oxide (AO) to the NH functional group of the nitrogen-containing polymer (NP) is < 0.25, preferably 0.05 to 0.24 and more preferably 0.05 to 0.2, and wherein greater than 50 mol% of the alkylene oxide is based on ethylene oxide, propylene oxide and / or butane oxide, preferably butane oxide.

[0122] In the following preferred embodiments,

[0123] (1) In step a), the diamine or oligoamine (A) is TPTA or PEHA, and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether; and

[0124] In step b), no more than 0.25 mol, preferably 0.05 to 0.25 mol, more preferably 0.05 to 0.25 mol, of NH-functional groups per mol of nitrogen-containing polymer (NP) is used in propylene oxide or butylene oxide; or

[0125] (2) In step a), the diamine or oligoamine (A) is 3-(2-aminoethylamino)propylamine (N3-amine), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether; and

[0126] In step b), no more than 0.25 mol, preferably 0.05 to 0.25 mol, more preferably 0.05 to 0.25 mol, of NH-functional groups per mol of nitrogen-containing polymer (NP) is used in propylene oxide or butylene oxide; or

[0127] (3) In step a), the diamine or oligoamine (A) is N,N'-bis-(3-aminopropyl)-ethylenediamine (N4-amine), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, or 1,6-hexanediol diglycidyl ether; and

[0128] In step b), no more than 0.25 mol, preferably 0.05 to 0.25 mol, more preferably 0.05 to 0.25 mol, of NH-functional groups per mol of nitrogen-containing polymer (NP) is used in propylene oxide or butylene oxide; or

[0129] (4) In step a), the diamine or oligoamine (A) is triethylenetetramine (TETA), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether; and

[0130] In step b), no more than 0.25 mol, preferably 0.05 to 0.25 mol, more preferably 0.05 to 0.25 mol, of NH-functional groups per mol of nitrogen-containing polymer (NP) is used in propylene oxide or butylene oxide; or

[0131] (5) In step a), the diamine or oligoamine (A) is tris(2-aminoethyl)amine (TAEA), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, or 1,6-hexanediol diglycidyl ether; and

[0132] In step b), no more than 0.25 mol, preferably 0.05 to 0.25 mol, more preferably 0.05 to 0.25 mol, of NH-functional groups per mol of nitrogen-containing polymer (NP) is used in propylene oxide or butylene oxide; or

[0133] (6) In step a), the diamine or oligoamine (A) is diethylenetriamine (DETA), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether or 1,6-hexanediol diglycidyl ether, 1,3-neopentyl glycol diglycidyl ether or 1,4-cyclohexanediethanol diglycidyl ether; and

[0134] In step b), no more than 0.25 mol, preferably 0.05 to 0.25 mol, more preferably 0.05 to 0.25 mol, of NH-functional groups per mol of nitrogen-containing polymer (NP) is used in propylene oxide or butylene oxide; or

[0135] (7) In step a), the diamine or oligoamine (A) is triaminononane, and the compound containing at least two glycidyl ether groups is ethylene glycol diglycidyl ether or 1,4-butanediol diglycidyl ether; and

[0136] In step b), no more than 0.25 mol, preferably 0.05 to 0.25 mol, more preferably 0.05 to 0.25 mol, of NH-functional groups per mol of nitrogen-containing polymer (NP) is used in propylene oxide or butylene oxide; or

[0137] (8) In step a), the diamine or oligoamine (A) is tetraethylenepentamine (TEPA), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether or 1,4-butanediol diglycidyl ether or diglycidyl ether; and

[0138] In step b), no more than 0.25 mol, preferably 0.05 to 0.25 mol, more preferably 0.05 to 0.25 mol, of NH-functional groups per mol of nitrogen-containing polymer (NP) is used in propylene oxide or butylene oxide; or

[0139] (9) In step a), the diamine or oligoamine (A) is pentaethylenehexamine (PEHA), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether; and

[0140] In step b), no more than 0.25 mol, preferably 0.05 to 0.25, more preferably 0.05 to 0.22 mol of NH-functional group per mol of nitrogen-containing polymer (NP), is used in propylene oxide or butylene oxide.

[0141] Optionally, alkoxylated nitrogen-containing polymers can be suitably used to capture carbon dioxide from a gas mixture. A gas mixture means carbon dioxide and at least one other gas. Desiredly, the gas mixture is atmospheric air or any kind of exhaust gas. Typically, exhaust gas can be, for example, gases emitted from industrial processes (including power plants). Additionally, exhaust gas can be generated by various other devices such as heating devices (including commercial and domestic boilers) or other devices such as motion-generating devices (e.g., vehicle combustion engines).

[0142] In a preferred aspect of use, the alkoxylated nitrogen-containing polymer may optionally be incorporated into a formulation for the direct capture of carbon dioxide, preferably the formulation being an alkoxylated nitrogen-containing polymer on a solid carrier or optionally the alkoxylated nitrogen-containing polymer being in a liquid composition, such as in an aqueous solution.

[0143] More preferably, the alkoxylated nitrogen-containing polymer is optionally supported on a solid inorganic support (SIS). The solid inorganic support (SIS) preferably has a primary particle size of 5 to 200 nm, for example, in the range of 5 to 50 nm, and exhibits a secondary particle size structure of 5 to 500 µm, preferably 30 to 300 µm.

[0144] Suitablely, the solid inorganic support (SIS) is a particulate or macroscopic support. The solid inorganic support (SIS) can be a porous support. Such porous solid inorganic supports (SIS) can include clay. Typically, such clay can include one or more of the following: bentonite, attapulgite, kaolinite, montmorillonite, spherical clay, bleaching clay, lithium montmorillonite, palygorskite, saponite, and sepiolite and halloysite. Desiredly, porous solid inorganic supports (SIS) can include silica, such as nano-silica, especially fumed silica or precipitated silica; titanium dioxide; magnesium oxide (MgO); aluminum oxide, such as γ-alumina; silica-alumina (SiO2-Al2O3); zinc chloride hydrate; calcium sulfate; zeolite, such as natural or synthetic zeolite.

[0145] Suitablely, the solid inorganic carrier (SIS) can be any commercially available silica, including fumed silica such as AEROSIL® from Evonik, CAB-O-SIL® from Cabot, and REOLOSIL® from Tokuyama; precipitated silica such as HI-SIL® from PPG Industries, SIPERNAT® from Evonik, and FIESIL® and TOKUSIL® from Tokuyama.

[0146] Optionally, the alkoxylated nitrogen-containing polymer can be supported on an organic solid support, such as activated carbon (e.g., activated charcoal); an organic non-polymer support; or a polymer support. In another alternative embodiment, the alkoxylated nitrogen-containing polymer can be supported on an inorganic-organic solid support comprising both inorganic and organic components, for example, in the form of a composite entity.

[0147] Solid inorganic carriers (SIS), solid organic carriers, or solid inorganic-organic solid carriers can take the form of hollow or solid particles, beads, microspheres, sheets, hollow or solid fibers, monolithic structures, membranes, and honeycomb structures. Preferably, the solid inorganic carriers (SIS), organic solid organic carriers, or solid inorganic-organic carriers are microparticles, and these can be in the form of powders or granules. The average particle size (D50) is in the range of 0.002 to 5 mm, for example, 0.01 to 4 mm, typically 0.25 mm to 4 mm.

[0148] In one embodiment, the solid inorganic support (SIS), solid organic support, or solid inorganic-organic solid support (preferably a solid inorganic support (SIS)) is porous and has a surface area greater than 50 m² / g. In some embodiments, the surface area is greater than 10 m² / g and less than 5000 m² / g. In some other embodiments, the surface area is greater than 25 m² / g and less than 1000 m² / g. In other embodiments, the surface area is from 50 m² / g to 500 m² / g, for example from 75 m² / g to 300 m² / g, for example from 100 m² / g to 120 m² / g. In some embodiments, the surface area is from 200 m² / g to 400 m² / g, for example from 200 m² / g to 300 m² / g.

[0149] The surface area of ​​a porous carrier can be determined according to DIN ISO 9277:2003-05 (a revision of DIN 66131) using the Brunauer-Emmett-Teller (BET) method. Specific surface area can be determined by multi-point BET measurements within a relative pressure range of 0.05–0.3 p / p0.

[0150] In another embodiment, the solid inorganic support (SIS), solid organic support, or solid inorganic-organic solid support (preferably a solid inorganic support (SIS)) is porous and has an average pore volume in the range of 0.1 cm³ / g to 3.0 cm³ / g, for example, 0.2 cm³ / g to 0.8 cm³ / g. The average pore volume can be determined according to the Barrett-Joyner-Halenda (BGH) method for determining pore volume.

[0151] The preferred solid inorganic support (SIS) is selected from silica supports or alumina supports. Preferably, the silica support or alumina support can cover any of the foregoing embodiments.

[0152] In any of the foregoing embodiments, optionally, the alkoxylated nitrogen-containing polymer can be impregnated onto or into such a solid support, preferably a solid inorganic support (SIS), more preferably wherein the solid inorganic support (SIS) is porous, particularly selected from silica or alumina supports, by any known and conventional technique for impregnating amines or polyamines onto or into a solid support.

[0153] In one embodiment, the optionally alkoxylated nitrogen-containing polymer can be impregnated into a particulate solid support (e.g., porous silica) by introducing the particulate solid support into a suitable container, typically used to prepare particles or granules of a porous solid (e.g., silica) impregnated with an amine or polyamine. Typically, such a container can be a disc granulator or a ball granulator. The optionally alkoxylated nitrogen-containing polymer can then be introduced into the container and mixed with the porous solid (e.g., silica), for example by rotating the container (typically as a granulation device), such as by rotating the disc of a disc granulator or the drum of a ball granulator. Suitably, this method will result in the formation of wet particles, which can be dried at a high temperature (e.g., between 40°C and 70°C) under an inert atmosphere (typically nitrogen) for 1 to 4 hours. The particles thus formed and impregnated with the optionally alkoxylated nitrogen-containing polymer can then be used to capture carbon dioxide from a gas mixture.

[0154] Particularly preferred embodiments relate to the use of optionally alkoxylated nitrogen-containing polymers in direct air capture (DAC). Direct air capture (DAC) involves techniques for the direct extraction of carbon dioxide from the atmosphere. This technique typically relies on the use of carbon dioxide adsorbents that can initially adsorb carbon dioxide directly from the air and then subsequently desorb the carbon dioxide in a controlled environment, where the carbon dioxide can be further processed to produce a more permanent carbon dioxide storage.

[0155] The alkoxylated nitrogen-containing polymer according to the invention can optionally be used as an adsorbent in direct air capture (DAC) to initially capture carbon dioxide directly from the air. Optionally, the alkoxylated nitrogen-containing polymer can be used suitably in the form of a suitable formulation, for example in a liquid formulation or preferably in a suitable solid carrier, more preferably impregnated onto or in a porous solid inorganic adsorbent (SIS), for example in particulate form.

[0156] The following examples are illustrative of the present invention, but do not limit the scope of the invention.

[0157] Example

[0158] Program A

[0159] In the case of a higher ratio of bridging compound (1.3 equivalents), the amine compound was diluted in methanol to produce a 50% solution.

[0160] 1 mol of the amine compound was placed in a 500 mL four-necked flask equipped with an anchor stirrer, a reflux condenser, and a dropping funnel. The solution was heated to 35°C and stirred at 150 rpm. The diglycidyl compound was added metered through the funnel over 90 minutes. After another 30 minutes, the viscous liquid was transferred to a rotary evaporator (Büchi) and the solvent was removed at 90°C to obtain a viscous liquid.

[0161]

[0162] Program B

[0163] 1 mol of the amine compound was placed in a 500 mL three-necked flask equipped with an anchor stirrer and a dropping funnel. The amine compound was heated to 50°C and stirred at 150 rpm while the diglycidyl compound was added metered through the funnel over 90 minutes, always keeping the temperature below 85°C. The reaction mixture was kept at 80°C for another 1 h and then cooled to room temperature (RT) to produce a viscous product.

[0164]

[0165]

[0166] Comparison Examples

[0167] Program D

[0168] A 50% aqueous solution of PEHA and TEPA was metered into a 1 L autoclave equipped with a stirrer. The epoxide was metered over 90 minutes at 40°C. The reaction temperature was raised to 95°C and maintained for 2 hours, then stirred again overnight at room temperature (RT). The mixture was transferred to a 2 L Büchi flask, and water was removed at 80°C and 100 mbar. A pale yellow liquid was obtained.

[0169]

[0170]

[0171]

[0172] Examples 6 and 9 were further propoxylated with 1.5 mmol PO / g polymer to produce Examples 19 and 20.

[0173] Example 19

[0174] 250 g of polymer Example 6 was charged into a 1 L stainless steel reactor equipped with a stirrer, followed by 250 g of water. The reactor was evacuated (60 mbar) and purged three times with nitrogen while the temperature was increased to 100°C. The reactor was pressurized to 2 bar, and 21.8 g of propylene oxide (PO) was added over 5 minutes. The temperature was increased to and maintained at 115°C while stirring at 150 rpm for 3.5 hours. The reactor was then cooled to 60°C and depressurized. Finally, the reactor was treated at 100 mbar for 10 minutes and purged with nitrogen. 520 g of a slightly yellowish liquid was obtained.

[0175] Example 20

[0176] Repeat the procedure of Example 19 using 250 g of polymer (Example 9).

[0177] In addition, CO2 absorption was studied before and after loading amine adsorbents onto silica and storing them in air at 90°C for 14 days.

[0178] Determining the balance load using CO2

[0179] Balanced loading was determined in a bubble column reactor as described below: BRECHTEL, K. Einflussder Molekülstruktur auf die -Abtrennung mit wässrigen Aminlösungen ausRauchgasen fossil befeuerter Kraftwerke. Dissertation / PhD, University of Stuttgart, 2011; A. Schäffer, Amine und Aminmischungen zur -Absorption aus Kraftwerksrauchgasen und ihr Energiebedarf zur Regeneration Dissertation / PhD, University of Stuttgart, 2013.

[0180] In this process, 0.15 kg of sample was diluted with 0.15 kg of water to obtain a 50% aqueous solution. The sample was heated in a water bath on an adjustable heating plate and exposed to a synthetic flue gas flow of 2 l / min, composed of 15% CO2, 5% O2, and 80% N2 by volume. The flue gas was injected into the sample via a glass frit (orifice 1) using a mass flow controller to achieve good mixing and a large mass transfer area. The exiting (excess) low-CO2 gas flow was fed into the infrared gas analyzer via a reflux and sample gas cooler. The reflux cooler condensed the evaporated water or solvent and fed it back into the sample. The gas composition was continuously measured using the infrared gas analyzer and recorded via a computer interface.

[0181] The sample mass [kg] was then equilibrated with the CO2 concentration in the flue gas or with the current CO2 partial pressure. The volume of CO2 absorbed by the solvent [m³] was derived from the integral formation over time [min]. The inflow flue gas volumetric flow rate [l / min] was constant. The equilibrium loading was then calculated as a percentage of CO2 by weight relative to 50% of the sample solution mass. For this purpose, the equilibrium loading was determined at 50°C.

[0182] Table 2

[0183]

[0184]

[0185] To determine resistance vs evaporation, the amines of Examples 1-20 and the comparative examples were absorbed onto a silica compound (using silica as described in the patent of the University of California – Sipernat 50S2, Evonik ResourceEfficiency GmbH).

[0186] Examples of silica-loaded adsorbents were obtained by treating 50% aqueous solutions of Examples 1-20 and the comparative examples with Sipernat 50S2 at a 1:1 ratio. After solvent evaporation (90°C, 100 mbar), 100 g of adsorbent was stored at 90°C in an atmosphere containing 95% CO2 and 5% O2 for 14 days. Every 48 hours, the adsorbent was evacuated for 90 minutes at a desorption temperature of 40 mbar and 105°C, and then stored again in a CO2 / O2 atmosphere, corresponding to 10 cycles after 20 days.

[0187] Table 3. CO2 absorption of 50% amine adsorbent on silica before and after 20 days of storage at 90°C and 10 adsorption-desorption cycles.

[0188]

[0189]

Claims

1. Use of an optionally alkoxylated nitrogen-containing polymer in carbon dioxide capture, the optionally alkoxylated nitrogen-containing polymer being obtained by a method comprising the following steps: a) React (i) a diamine or oligoamine (A) with (ii) a bridging compound (BC), The bridging compound (BC) (I) is phosgene; or (II) Contains at least two amine reactive groups (ARG), The bridging compound (BC) can bond to the amine groups of at least two diamine or oligoamine (A) molecules. To provide nitrogen-containing polymers (NP), The nitrogen-containing polymer (NP) comprises a bridging compound (BC) molecular component bonded to at least two molecular components of a diamine or oligoamine (A), and the proportion of bridging compound (BC) molecules bonded to at least two molecules of diamine or oligoamine (A) is the bridging factor (BF) of the nitrogen-containing polymer (NP), wherein the bridging factor (BF) is greater than 50%. The total amount of primary and secondary amine groups in the nitrogen-containing polymer (NP) is at least 600 mg KOH / g. Furthermore, the number-average molecular weight (Mn) of the nitrogen-containing polymer (NP) is greater than 600 g / mol, and b) Optionally, the nitrogen-containing polymer (NP) may be reacted with an alkylene oxide (AO), preferably selected from the group consisting of at least one of ethylene oxide (EO), propylene oxide (PO), and butane oxide (BuO), wherein the molar ratio of the alkylene oxide (AO) to the NH functional group of the nitrogen-containing polymer (NP) is not greater than 0.

25. In order to obtain an alkylene oxide side chain (AB) attached to the nitrogen atom of the nitrogen-containing polymer (NP), thereby providing the alkoxylated nitrogen-containing polymer (ANP).

2. The use according to claim 1, wherein, The bridging compound (BC) is (1) The reaction product formed by reacting (i) a diol or polyol with (ii) epichlorohydrin; or (2) A compound containing at least two amine reactive groups (ARGs), the compound being selected from compounds containing at least two glycidyl ether groups or compounds containing at least two isocyanate groups; or (3) Phosphorus.

3. The use according to claim 1 or claim 2, wherein, The bridging compound (BC) is a compound containing at least two glycidyl ether groups, and is such a compound as follows: (i) Contains at least twice the structure according to formula (I) (I) The dashed lines indicate bonds to the remainder of the compound containing at least two glycidyl ether groups, preferably the compound containing at least two glycidyl ether groups having twice the structure according to formula (I); and / or (ii) Select from the group consisting of: 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, diglycidyl ether, 1,3-neopentyl glycol diglycidyl ether, 1,4-cyclohexanediethanol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol triglycidyl ether and trimethylolpropane triglycidyl ether.

4. The use according to claim 2, wherein, The diol or polyol is selected from the group consisting of: 1,4-butanediol, 1,6-hexanediol, 1,3-neopentylenediol, 1,4-cyclohexanediol, glycerol, and trimethylolpropane.

5. The use according to any one of claims 1 to 4, wherein, The at least one diamine or oligoamine (A) (i) having at least 2 amino groups, suitably 2 to 12 amino groups, preferably 2 to 8 amino groups, more preferably 3, 4, 5, 6, 7 or 8 amino groups; (ii) having at least one carbon atom per nitrogen atom, preferably 1 to 5 carbon atoms per nitrogen atom, more preferably 1 to 3 carbon atoms per nitrogen atom; (iii) Contains at least two primary amino groups and / or secondary amino groups, preferably at least two primary amino groups; (iv) Having a molecular weight (Mw) in the range of 50 to 500 g / mol, preferably in the range of 60 to 300 g / mol, more preferably 80 to 250 g / mol, even more preferably 120 to 250 g / mol, and particularly preferably 150 to 250 g / mol; and / or (v) Select from the group consisting of: ethylenediamine, hexamethylenediamine, methylcyclohexanediamine (MCDA), propylenediamine (PDA), tetramethylenediamine (TMDA), pentamethylenediamine (PMDA), dipropylenetriamine (DPTA), tripropylenetetramine (TPTA), tri(2-aminoethyl)amine (TAEA), tetrapropylenepentamine (TPPA), N,N'-bis-(3-aminopropyl)ethylenediamine (N4-amine), 3-(2-aminoethylamino)propylamine (N3-amine), spermine, spermidine, triaminononane, diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), pentaethylenehexamine (PEHA), and compounds according to formulas (II) to (X). (II) (III) (IV) (V) (VI) (VII) (VIII) (IX) (X)。 6. The use according to any one of claims 1 to 5, wherein, The molar ratio of the bridging compound (BC) to the diamine or oligoamine is 0.35 to 0.85, preferably 0.4 to 0.8, and more preferably 0.45 to 0.

75.

7. The use according to any one of claims 1 to 6, wherein, The molar ratio of the epoxy group of the bridging compound (BC) to the NH functional group of the diamine or oligoamine is less than 0.5, preferably up to 0.45, and more preferably from 0.15 to 0.

4.

8. The use according to any one of claims 1 to 7, wherein, The optional alkoxylated nitrogen-containing polymer is an alkoxylated nitrogen-containing polymer (ANP), and the molar ratio of alkyl epoxide (AO) to NH functional group is 0.05 to 0.25, more preferably 0.05 to 0.

2.

9. The use according to any one of claims 1 to 8, wherein, The alkoxylated nitrogen-containing polymer (ANP) contains structural elements according to formula (XI). (XI) in The dashed lines indicate the bonds with the remaining portion of the alkoxylated nitrogen-containing polymer; and AB represents an alkylene oxide side chain.

10. The use according to any one of claims 1 to 9, wherein, Optional alkoxylated nitrogen-containing polymers have a higher weight-average molecular weight (Mi) than the diamine or oligoamine (A). W At least 70% greater than the weight-average molecular weight (M). W ).

11. The use according to any one of claims 1 to 10, wherein, The optionally alkoxylated nitrogen-containing polymer has a number-average molecular weight (Mn) in the range of 600 to 150,000 g / mol, more preferably in the range of 600 to 75,000 g / mol, more preferably in the range of 600 to 50,000 g / mol, for example 600 to 20,000 g / mol, preferably 600 to 10,000 g / mol, more preferably 800 to 5000 g / mol, more preferably 600 to 2500 g / mol, and even more preferably 1000 to 2500 g / mol.

12. The use according to any one of claims 1 to 11, wherein, This optional alkoxylated nitrogen-containing polymer is (i) Water-soluble; and / or (ii) Branched polymers.

13. The use according to any one of claims 1 to 12, wherein, Less than 10%, preferably less than 5%, of the nitrogen atoms present in the optionally alkoxylated nitrogen-containing polymer are quaternized.

14. The use according to any one of claims 1 to 13, wherein, Optionally, the alkoxylated nitrogen-containing polymer is alkoxylated, and the molar ratio of the alkyl epoxide (AO) to the NH functional group of the nitrogen-containing polymer (NP) is 0.05 to 0.25 and preferably 0.05 to 0.2, wherein more than 50 mol% of the alkyl epoxide is based on ethylene oxide, propylene oxide and / or butyl oxide, preferably propylene oxide or butyl oxide.

15. The use according to any one of claims 1 to 14, wherein, (1) In step a), the diamine or oligoamine (A) is TPTA or PEHA, and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether; and In step b), less than 0.25 mol of propylene oxide or butane oxide is used per mol of nitrogen-containing polymer (NP) with an NH-functional group; or (2) In step a), the diamine or oligoamine (A) is 3-(2-aminoethylamino)propylamine (N3-amine), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether; and In step b), less than 0.25 mol of propylene oxide or butane oxide is used per mol of nitrogen-containing polymer (NP) with an NH-functional group; or (3) In step a), the diamine or oligoamine (A) is N,N'-bis-(3-aminopropyl)-ethylenediamine (N4-amine), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or 1,6-hexanediol diglycidyl ether; and In step b), less than 0.25 mol of propylene oxide or butane oxide is used per mol of nitrogen-containing polymer (NP) with an NH-functional group; or (4) In step a), the diamine or oligoamine (A) is triethylenetetramine (TETA), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether; and In step b), less than 0.25 mol of propylene oxide or butane oxide is used per mol of nitrogen-containing polymer (NP) with an NH-functional group; or (5) In step a), the diamine or oligoamine (A) is tris(2-aminoethyl)amine (TAEA), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, or 1,6-hexanediol diglycidyl ether; and In step b), less than 0.25 mol of propylene oxide or butane oxide is used per mol of nitrogen-containing polymer (NP) with an NH-functional group; or (6) In step a), the diamine or oligoamine (A) is diethylenetriamine (DETA), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether or 1,6-hexanediol diglycidyl ether, 1,3-neopentyl glycol diglycidyl ether or 1,4-cyclohexanediethanol diglycidyl ether; and In step b), less than 0.25 mol of propylene oxide or butane oxide is used per mol of nitrogen-containing polymer (NP) with an NH-functional group; or (7) In step a), the diamine or oligoamine (A) is triaminononane, and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether; and In step b), less than 0.25 mol of propylene oxide or butane oxide is used per mol of nitrogen-containing polymer (NP) with an NH-functional group; or (8) In step a), the diamine or oligoamine (A) is tetraethylenepentamine (TEPA), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether, diglycidyl ether, or ethylene glycol diglycidyl ether; and In step b), less than 0.25 mol of propylene oxide or butane oxide is used per mol of nitrogen-containing polymer (NP) with an NH-functional group; or (9) In step a), the diamine or oligoamine (A) is pentaethylenehexamine (PEHA), and the compound containing at least two glycidyl ether groups is 1,4-butanediol diglycidyl ether or ethylene glycol diglycidyl ether; and In step b), less than 0.25 mol of propylene oxide or butane oxide is used per mol of nitrogen-containing polymer (NP) with NH-functional groups.

16. The use according to any one of claims 1 to 15, wherein, This optional alkoxylated nitrogen-containing polymer is used to capture carbon dioxide from a gas mixture.

17. The use according to any one of claims 1 to 16, wherein, This optional alkoxylated nitrogen-containing polymer is incorporated into formulations for the direct capture of carbon dioxide. Preferably, the preparation contains (i) the alkoxylated nitrogen-containing polymer on a solid support; or (ii) the optional alkoxylated nitrogen-containing polymer in a liquid composition, such as in an aqueous solution.

18. The use according to claim 16 or claim 17, wherein, The gas mixture is atmospheric air or exhaust smoke.

19. The use according to any one of claims 1 to 18, wherein, The optional alkoxylated nitrogen-containing polymer is loaded on a solid inorganic support (SIS), which is suitably a particulate or macroscopic support, preferably a particulate, suitably a powder or granules.

20. The use according to claim 19, wherein, The solid inorganic carrier (SIS) is selected from silica or alumina carriers.

21. The use according to any one of claims 1 to 20, wherein, This optional alkoxylated nitrogen-containing polymer is used for direct air capture (DAC).

22. A method for capturing carbon dioxide, the method comprising contacting a gas mixture containing carbon dioxide with, optionally, an alkoxylated nitrogen-containing polymer, the optionally alkoxylated nitrogen-containing polymer being obtained by a method comprising the following steps: a) React (i) a diamine or oligoamine (A) with (ii) a bridging compound (BC), The bridging compound (BC) (I) is phosgene; or (II) Contains at least two amine reactive groups (ARG), The bridging compound (BC) can bond to the amine groups of at least two diamine or oligoamine (A) molecules. To provide nitrogen-containing polymers (NP), The nitrogen-containing polymer (NP) comprises a bridging compound (BC) molecular component bonded to at least two molecular components of a diamine or oligoamine (A), and the proportion of bridging compound (BC) molecules bonded to at least two molecules of diamine or oligoamine (A) is the bridging factor (BF) of the nitrogen-containing polymer (NP), wherein the bridging factor (BF) is greater than 50%. The total amount of primary and secondary amine groups in the nitrogen-containing polymer (NP) is at least 600 mg KOH / g. Furthermore, the number-average molecular weight (Mn) of the nitrogen-containing polymer (NP) is greater than 600 g / mol, and b) Optionally, the nitrogen-containing polymer (NP) is reacted with an alkylene oxide (AO), preferably selected from the group consisting of at least one of ethylene oxide (EO), propylene oxide (PO), and butane oxide (BuO), wherein the molar ratio of the alkylene oxide (AO) to the NH functional group of the nitrogen-containing polymer (NP) is not greater than 0.25, in order to obtain an alkylene oxide side chain (AB) attached to the nitrogen atom of the nitrogen-containing polymer (NP), thereby providing the alkoxylated nitrogen-containing polymer (ANP). The optional alkoxylated nitrogen-containing polymer (NP) is contacted with carbon dioxide.

23. The method according to claim 22, wherein, The optional alkoxylated nitrogen-containing polymer (NP) includes any one of the features described in claims 2 to 21.

Images