Systems and processes for carbon capture and conversion

Abstract

An active CO2 capture unit for capturing CO2 from a dilute source of CO2 inlet gas includes an inlet through which the inlet gas is introduced into the unit, and a gas separator in contact with the inlet gas to chemically adsorb CO2 from the inlet gas and convert the chemically adsorbed CO2 into OH. - By reacting with HCO3 - OH arranged to convert - and a non-aqueous region containing a non-aqueous CO2-binding organic liquid containing HCO3. The unit also includes an aqueous region disposed downstream of the non-aqueous region, the aqueous region interface containing HCO3 - interacts with H2O to form CO2 and CO3 2- The anion exchange membrane transfers HCO3 from the non-aqueous region to the aqueous region. - A CO2 capture outlet is disposed downstream of the aqueous region.

Description

[Technical field]

[0001] The present disclosure relates to systems and processes for the capture and conversion of CO2, and more specifically, from sources such as power plants and the chemical industry, and more generally, from the air, that can advantageously reduce the anthropogenic carbon footprint. [Background technology]

[0002] Brief description of the related art Currently, about 85% of the world's energy consumption is supplied by burning fossil fuels, such as oil, natural gas, and coal. Despite their low cost and high energy density, the use of fossil fuels is inevitably coupled with the emission of many undesirable compounds, such as carbon dioxide (CO2), which can cause several adverse effects on the environment, including ocean acidification, climate change, etc.

[0003] Conventional CO2 capture technologies include absorption, cryogenic distillation, adsorption, and membrane separation. Liquid absorbents such as monoethanolamine (MEA), diethanolamine, and aqueous hydroxide solutions are widely used in industry to selectively capture CO2. Amine-based processes suffer from solvent loss due to evaporation and high viscosity during CO2 absorption. The strong bond between CO2 and amine functional groups requires high temperatures, which negatively impacts the energy efficiency of the process. In the case of aqueous hydroxide solutions, HCO3 - from CO3 2-Conversion to Ca(OH)2 limits the CO2 capture capacity and results in high energy consumption to release the CO2. Another concern is the loss of water during the causticization-calcination process to regenerate Ca(OH)2 for hydroxide-based approaches. Low-temperature distillation is another established technique to cool CO2 below the sublimation temperature (-100 to -135 °C) to separate it from lighter gases. The temperature requirements of this process make it a highly energy-intensive process. Solid sorbents such as metal-organic frameworks (MOFs), CaO, and alkali metal carbonates exhibit adsorption efficiencies of >85% and act as membranes to separate CO2 from the mixture of gases in the feed, either by size exclusion or relative electrostatic attraction in a single-pass operation. All existing CO2 capture technologies require regeneration of the CO2 capture medium, making the process not only energy intensive but also discontinuous, as no CO2 is captured during this regeneration step. Process modifications such as chemical looping and the use of dual fluidized bed sorbents attempt to circumvent this challenge, but at the expense of higher energy consumption.

[0004] During the next few decades (2010-2060), the cumulative amount of CO2 in the atmosphere is projected to increase by up to about 496 gigatons due to fossil fuel combustion in existing infrastructure. Therefore, there is an urgent need for both alternative energy sources and improved control of CO2 emission rates. However, due to the high global energy demand, there are no immediate alternatives to replace or significantly reduce fossil fuel generation. This problem is further exacerbated by the low cost of fossil fuels. Fortunately, research on the electrocatalytic reduction of CO2 has led to incredible progress in the past few years, but there is still no known solution that can directly capture CO2 from air or other point sources and convert the captured CO2 emissions into value-added chemicals. Summary of the Invention

[0005] Water-driven CO2 capture technologies are attractive for their low energy penalty. Hydrate-based CO2 separation is a water-driven technology in which CO2 forms hydrates with water or water-miscible solvents under high pressure and can be separated from the feed with a mixture of gases. Moisture swing technology captures CO2 directly from air, where a quaternary amine ion exchange resin supported on a polymer backbone acting as an anion exchange membrane absorbs CO2 in the form of bicarbonate and carbonate in a water-depleted (dry) environment and releases it to CO2 in a humid environment via carbonate-bicarbonate equilibrium. This mechanism can be exploited by maintaining a constant water-depleted environment with a constant supply of CO2 on one side of the anion exchange membrane, and a humid environment on the other side, thereby establishing a gradient of water concentration across the anion exchange membrane.

[0006] Disclosed herein is an active CO2 capture unit that utilizes a CO2-binding organic liquid present within the non-aqueous regions of the unit to chemically adsorb CO2 from the inlet gas and convert it into HCO3 - This unit is an active CO2 capture unit that converts HCO3 - interacts with H2O, producing CO2 and CO3 2- HCO3 into the aqueous region where it is decomposed - The anion exchange membrane is disposed at the interface between the non-aqueous region and the aqueous region to facilitate the transfer of

[0007] Also disclosed herein is a system for capturing CO2 and converting the captured CO2 to one or more of C3H6, CH4, C2H4, C2H5OH, CH3OH, CO, H2, and CH3COOH. By-products of the system can include syngas (CO and H2) and O2. The disclosed system can be a fully integrated system that combines CO2 capture and conversion into a single process. This process can be sustainable and energy efficient.

[0008] In accordance with the principles of the present disclosure, an automated and fully integrated electrochemical system that combines CO2 capture and conversion into a single sustainable and energy-efficient process can capture CO2 emissions from ambient air and other point sources and convert the emissions to produce syngas (CO and H2) with tunable composition at ambient conditions. The syngas can be used as a feedstock for long chain hydrocarbon production, such as via the Fischer-Tropsch process.

[0009] Exemplary embodiments are described that include an integrated electrocatalytic membrane configured for efficient capture of CO2 from one or more dilution sources and / or gases at ambient conditions to form a product. The membrane can be constructed such that the supported ionic liquid can include one or more imidazole-based liquids, phosphonium-based liquids, or anion exchange membranes or resins. The product can be CH 4、 It may be further defined by at least one of C2H5OH, C3H6, CO, H2, CH3OH, and CH3COOH. In an exemplary embodiment, the capture and conversion of CO2 in the membrane may both occur within an integrated electrocatalytic membrane system. The one or more dilution sources / gases may include flue gas. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of a mechanism for CO2 capture and transport using a moisture gradient process in accordance with the present disclosure. [Diagram 2] FIG. 2 is a schematic diagram of a CO2 capture unit in accordance with the present disclosure. [Diagram 3] FIG. 3 is a schematic diagram of a system for CO2 capture and reduction in accordance with the present disclosure. [Figure 4] FIG. 4 is a schematic diagram of a system for CO2 capture and reduction in accordance with the present disclosure, with the inset showing a hollow fiber membrane module-based anion exchange membrane. [Figure 5A] FIG. 5A is a schematic diagram of a reduction unit with a Cu mesh catalyst according to the present disclosure. [Figure 5B]FIG. 5B is a schematic diagram of a reduction unit having a stack of Cu mesh catalyst in accordance with the present disclosure. [Figure 5C] FIG. 5C is a scanning electron microscope image of the Cu mesh catalyst. [Figure 5D] FIG. 5D is a graph illustrating an embodiment of an oscillating square wave potential of 2 V amplitude for the bath RHE (inset) varying from −1.4 V to 0.6 V showing the faradaic efficiency of ethylene at different frequencies (switching times) of the oscillating square wave potential. [Figure 6] FIG. 6 is a schematic diagram of a system for CO2 capture and conversion in accordance with the present disclosure. [Figure 7] FIG. 7(a) is a graph of the interdiffusion profiles of H2O and HCO3- for a multi-physics simulation of CO2 capture directly from air using a moisture gradient process. FIG. 7(b) is a graph of the CO2 and pH profiles for a multi-physics simulation of CO2 capture directly from air using a moisture gradient process. FIG. 7(c) is a graph showing the performance curve relationship between CO2 separation and capture efficiency of Excellion anion exchange membrane for a multi-physics simulation of CO2 capture directly from air using a moisture gradient process. FIG. 7(d) is a graph showing the experimentally measured pH change in 0.3 KOH electrolyte when air is directly sprayed (solid) compared to when Excellion (dashed line) is used as the contactor. The change in pH is related to CO2 capture. [Figure 8] FIG. 8 is a schematic diagram of a system according to the present disclosure. [Figure 9] FIG. 9 is a graph of separation efficiency as a function of capture efficiency for a capture unit of the present disclosure. [Figure 10A] Figure 10A shows the FTIR spectra of pure CH3OH(MeOH), NaOH dissolved in MeOH, CO2-sprayed NaOH+MeOH solution, and CO2-sprayed NaOH+MeOH solution with added H2O. The HCO3-stretch is dominant in the CO2-sprayed NaOH+MeOH solution, which decreases with an increase in the CO3 2-stretch with increasing H2O. [Figure 10B] FIG. 10B shows that log(K) increases rapidly with increasing H2O, reaching a plateau corresponding to a bulk pKa of -3.87 for HCO3 -aqueous solutions. [Figure 11] Figure 11A is a calibration curve showing the nearly linear dependence of solution resistance on the concentration of HCO3-, and Figure 11B is a graph showing the total moles of CO2 captured in a solution of 1.2 M KOH in ethylene glycol. The average CO2 capture rate is about 8.3 μmol / sec. [Figure 12] FIG. 12 is a graph of resistance as a function of time showing that the higher the concentration of CO2 in the inlet gas, the less time it takes to become fully saturated with bicarbonate ions. [Figure 13] FIG. 13 is a graph showing the dynamic increase in HCO3 −, dissolved, and gaseous CO2 concentrations due to the migration of HCO3 − from the organic solution. [Figure 14] FIG. 14 is a graph of pH as a function of time showing the amount of CO2 transferred over time as observed by a drop in pH. [Figure 15A] FIG. 15A is a graph of pH as a function of time showing the effect of the integration of both capture and reduction processes on the transport process. [Figure 15B] FIG. 15B is a graph of pH as a function of time showing the effect of the integration of both capture and reduction processes on the transport process. [Figure 16] FIG. 16 is a graph showing the percentage of FE halide as a function of applied potential for different catalysts in a system of the present disclosure. [Figure 17A] FIG. 17A is a graph showing the total current for the #40 mesh Cu catalyst, the #100 female catalyst, and the foam Cu catalyst. [Figure 17B] FIG. 17B is a graph showing the ethylene partial current for the #40 mesh Cu catalyst, the #100 mesh Cu catalyst, and the foam Cu catalyst. [Figure 18] FIG. 18 is a graph showing current density as a function of Cu mesh. [Figure 19] FIG. 19 is a graph showing ethylene partial current as a function of Cu mesh. [Figure 20A] FIG. 20A is a graph showing sine and square type oscillatory waves. [Figure 20B] FIG. 20B is a graph showing ethylene FE percentage as a function of oscillatory wave amplitude. [Figure 20C] FIG. 20C is a graph showing FE percentage as a function of vibration wave amplitude. [Figure 21] FIG. 21 is an experimental setup for evaluating the carbon capture efficiency of anion exchange membranes in the presence of a moisture gradient. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] A moisture gradient process for CO2 capture and a unit for carrying out such a process are disclosed herein. Additionally, a process for the capture and reduction of CO2 to a desired product and a system for carrying out the same are also disclosed herein. Such a system may be an integrated system for carrying out both the capture and reduction processes. The capture unit of the present disclosure can advantageously capture CO2 from dilute sources such as flue gas, other industrial gases, and air, and release substantially pure CO2. In the system of the present disclosure, the released CO2 can be reduced with by-products generated during the process being recycled to the process, allowing for a continuous or substantially continuous process. Intermittent processes for capture and reduction are also contemplated herein.

[0012] Referring to FIG. 1, the CO2 capture process of the present disclosure is a reaction in which HO autocatalyzes the reaction. [ka] Without intending to be bound by theory, the reaction mechanism is autocatalytic HCO3 - It is thought to represent decomposition. [ka]

[0013] According to Le Chatelier's principle, HCO3 in the membrane - Increasing the concentration of HCO3 in the membrane increases the concentration of CO2 at the aqueous interface (wet interface) where the relative humidity (RH) of the water is maintained at 100%. - A higher concentration of is obtained by reducing the H2O concentration at the non-aqueous (dry) interface, and therefore the CO2 and CO3 at the dry interface. 2- H bridging molecules 2 O splits into two molecules of HCO3 - produces.

[0014] 2, an active CO2 capture device 10 of the present disclosure can include an inlet gas inlet 12 for introducing an inlet gas into a non-aqueous region 14 of the capture unit 10 for capture of CO2 from the inlet gas. The capture unit further includes an aqueous region 16 downstream of the non-aqueous region 14, with an anion exchange membrane 18 disposed between the aqueous region 16 and the non-aqueous region 14, such that a moisture gradient is created across the anion exchange membrane 18. Alternatively, the unit 10 can be operated as a membrane electrode unit, with a cathode 20 provided within the non-aqueous region 14 for the decomposition of HO to produce OH in the non-aqueous region 14. - In such a unit, H2O from the aqueous region is reduced on the cathode to produce H2 gas and OH. H2 gas bubbles up and OH - reacts with CO2 in the input steam to produce HCO3 - Generate OH - The continuous production of HCO3 - This ensures continuous capture of CO2.

[0015] The capture unit 10 of the present disclosure may further include a cathode 20 disposed in or upstream of the non-aqueous region 14 for operation as a membrane electrode unit or for use in a capture unit having a CO2-binding organic liquid in the non-aqueous region. The cathode 20 converts HO into H2 gas and OH - This can function in the aqueous region n14 by binding CO2 and reducing HCO3 - H2 outlet 28 may be positioned to allow H2 gas escaping from the reduction of H2O to be vented from unit 10.

[0016] The capture unit 10 of the present disclosure may further include an anode 22 disposed downstream of the aqueous region. In the capture unit 10 of the present disclosure having a cathode 20 and an anode 22, the aqueous region 16 may include an aqueous electrolyte, and an electric field may be applied to drive HCO3 from the non-aqueous region 14 to the aqueous region 16. - In an embodiment, an electric field may be generated and applied within the capture unit to promote the movement and diffusion of the.

[0017] Either or both of the anode 22 and the cathode 20 can be planar and / or porous. Referring to Figure 3, in a system 100 of the present disclosure having a capture unit 10 and a reduction unit 30, the cathode 20 can be disposed upstream of the capture unit and the anode 22 can be disposed downstream of the reduction unit 30, as described in more detail below.

[0018] The non-aqueous region 14 contacts the inlet gas and chemically adsorbs CO2 from the inlet gas and converts the chemically adsorbed CO2 into OH. - and / or OH - By reaching the source of HCO3 - is arranged to convert to OH -The CO2-binding organic liquid may include a CO2-binding organic liquid containing the above-mentioned. The CO2-binding organic liquid may be, for example, an ionic liquid. The ionic liquid may be an imidazolium-based or phosphonium-based. For example, the ionic liquid may be one or more of choline hydroxide, tetrabutylphosphonium methanesulfonate, and 1-butyl-3-methylimidazolium hexafluorophosphate.

[0019] The hydroxide ion source can be, for example, an alkali metal hydroxide. The hydroxide ion source can be dissolved in the CO2-binding organic liquid. For example, the hydroxide ion source can be KOH.

[0020] The non-aqueous region 14 may further include a non-aqueous polar organic solvent. The non-aqueous polar solvent may be one or more of an alcohol, an organic amidine base, or a guanidine base. The amidine or guanidine base may chemically bond with CO2 as a liquid amidinium or guanidinium alkyl carbonate. For example, the solvent may be one or more of ethylene glycol, methanol, and ethanol.

[0021] Alternatively, the unit 10 can be operated as a membrane electrode unit with a dry side in which a cathode 20 is provided upstream of the non-aqueous region 14 and an anion exchange membrane 18 functions to bind CO2 from the inlet gas stream onto the non-aqueous region 14 of the unit. The anion exchange membrane 18 reacts with OH groups around the quaternary amines. - The ion may be or may include an associated quaternary amine. OH - reacts with CO2 to produce HCO3 - In such a unit 10, HO is reduced by the cathode to form H gas and OH - The H2 gas bubbles up and produces OH - reacts with CO2 in the input steam to produce HCO3 - Generate OH - The continuous production of HCO3 -In some units 10, the anion exchange membrane 18 can be coated with a CO binding agent to further promote binding, such as in systems that use a CO organic binding liquid.

[0022] The aqueous region 16 contains HO either in liquid form, such as pure water or in the presence of aqueous electrolytes, or in humidified gas (collectively referred to herein as aqueous fluid). The aqueous fluid can flow through the aqueous region or can be provided in fixed amounts. In the aqueous region, HCO - interacts with H2O to produce CO2 and CO3 2- Decompose into:

[0023] The anion exchange membrane 18 can include one or more quaternary amines or phosphonium ions. The anion exchange membrane can be, for example, a polymer backbone resin having hydroxide, carbonate, and / or bicarbonate moieties attached thereto. The polymer backbone can be, for example, polystyrene. Referring to the insert of FIG. 4, the anion exchange membrane can be constructed of hollow fibers. The anion exchange membrane can be formed of a material that can withstand a high pH, ​​such as a pH greater than 10. For example, the presence of hydroxide, carbonate, and bicarbonate moieties on the polymer backbone as counterions can enable the anion exchange membrane to maintain a pH greater than 10.

[0024] The capture rate can be adjusted by adjusting the specific area of ​​the anion exchange membrane. Higher specific area configurations such as hollow fibers or porous carbon or other suitable substrates can increase the rate and amount of CO2 capture. For example, 1 cm 2 Geometric area of ​​527 cm 2 The anion exchange membrane hollow fiber structure with a specific area of 2 The concentration was kept at 22 mM while the current density was 350 mA / cm 2CO2 can be supplied to the cathode from ambient air to support approximately 100 μmol m -2 s -1 This compares well with the experimentally measured CO2 capture fluxes.

[0025] The capture unit 10 may further include an inlet gas outlet 24 in fluid communication with the inlet gas such that the inlet gas flows into the capture unit 10 through the inlet gas inlet 12 for capture of CO2 and the remaining components of the gas are removed from the unit 10 through the inlet gas outlet 24.

[0026] The inlet gas is any gas that contains CO2 and from which CO2 is captured. For example, the inlet gas can be a dilute source of CO2, such as flue gas, other industrial gases, air, or other anthropogenic sources of CO2. Dilute sources of CO2 can include flue gas containing about 10-15% CO2 in the stream and air containing greater than about 400 ppm CO2. The inlet gas can be at a temperature of about 20°C to about 120°C.

[0027] The capture units of the present disclosure can achieve high separation efficiencies while maintaining CO2 capture efficiency. With reference to FIG. 9, for example, a CO2 separation efficiency of 80% can be achieved while maintaining a CO2 capture efficiency of about 80%. The capture units and systems of the present disclosure can have a CO2 separation efficiency and / or CO2 capture efficiency of 60% to 90%. The capture and separation efficiencies are calculated as follows:

number

[0028] Here, "dry" refers to non-aqueous regions and "wet" refers to aqueous regions.

[0029] The capture units and systems for capture and reduction of the present disclosure can operate in ambient conditions. The capture units and capture and reduction systems of the present disclosure can operate in low humidity environments. This advantageously allows the capture units to be used in a variety of manufacturing or other environments, such as indoors in residential, commercial, or industrial environments, and outdoors in open areas.

[0030] With reference to Figures 3 and 4, a system 100 for active CO2 capture and reduction can include any of the capture units 10 described herein with a reduction unit 30 for converting the captured CO2 to a desired product gas. The desired product gas includes one or more of C2H4, C2H5OH, CH3COOH, C3H6, CH3OH, CH4, CO, and H2. The system can have integrated capture and reduction. With reference to Figure 6, the system can be configured to receive dehumidified flue gas from the boiler system and have a delivery outlet configured to release the converted output gas from the system. The system of the present disclosure can be tuned to produce CO and H2 (syngas), which can be recycled to serve as a secondary fuel for the boiler for continued operation.

[0031] The reduction unit 30 is disposed downstream of the active CO2 capture unit 10 such that the reduction unit receives captured CO2 from a CO2 capture outlet disposed in an aqueous region where the captured CO2 is released through reaction with H2O. The reduction unit includes a catalyst 32 for the reduction of captured CO2 such that when captured CO2 flows to the reduction unit 30, it interacts with the catalyst 32 and is reduced to one or more of C2H4, C2H5OH, CH3COOH, C3H6, CH3OH, CH4, CO, and H2. The system 10 further includes a catalyst 36 for the oxidation of H2O to produce protons for CO2 reduction and O2 as a by-product. A separator 38 is disposed between the reduction unit 30 and the H2O oxidation catalyst 36. The H2O oxidation catalyst 36 can be part of the system or otherwise form the anode for the system. The H2O oxidation catalyst can include, for example, one or more of Ni, Fe-Ni, Pt-coated Ti, Ir, and Ru. In the system, a cathode can be provided upstream of the capture unit or as part of the capture unit, as described herein. The system can also include an energy source. The energy source can be, for example, a photocell and / or an electrochemical cell. The energy source can be integrated with the carbon capture unit 10 or can be integrated into a stand-alone device within the system.

[0032] The CO2 reduction catalyst can be a copper mesh. For example, the copper mesh can have a mesh size of about 40 to about 120 mesh. Suitable mesh sizes include about 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, and 120, as well as any value therebetween or ranges defined by values ​​therebetween.

[0033] The CO2 reduction catalyst may include or be formed as metal nanocrystals. For example, the metal nanocrystals may be grown on a mesh substrate. For example, Cu nanocrystals may be used as the CO2 reduction catalyst. The Cu nanocrystals may be Cu nanocubes with dominate (100) facets. The catalyst may be prepared, for example, by spray coating a Cu-nanocube nanoparticle ink onto carbon paper or by electrodeposition. The metal nanocrystals may be formed in different sizes and shapes and may be formed by cyclic oxidation-reduction of polycrystalline metal films such as Cu.

[0034] In the system of the present disclosure, the CO2 capture unit 10 and the reduction unit 30 may be separated by a distance of about 5 mm to about 20 mm.

[0035] A method for capturing CO2 can include flowing an inlet gas containing the CO2 to be captured through a CO2 capture unit as described herein. When the inlet gas is introduced into a non-aqueous region of the capture unit, OH - and / or OH groups present on or associated with the anion exchange membrane. - CO2-binding organic liquids containing - Convert to HCO3 - The anion exchange membrane moves across a water gradient in the aqueous domain. The water gradient drives the transport across the membrane. The method involves the transfer of HCO3 - The method may further include applying an electric field across the capture unit to further assist in the transport of HCO3. The applied electric field may be applied as a static voltage in the range of about 3 to about 10 V. Optionally, the applied electric field may be generated within the system. In the aqueous region, HCO3 - may interact with H2O present in the aqueous region and decompose into CO2, which may flow to the captured CO2 outlet.

[0036] As discussed above, the capture unit or the system containing the capture unit 10 may be configured such that H2O is converted into H2 and OH -The cathode 20 may include a cathode 20 in which H2 is reduced to OH. H2 may be bubbled and released upstream of the capture unit. - The water can be continuously flowed to the capture unit as humidified nitrogen and / or recirculated through the capture unit to provide continuous OH to the non-aqueous region for continuous binding activity. - The H released from the reduction of H0 by the cathode can be used to power the reduction unit or can be oxidized to generate protons for the reduction.

[0037] In the disclosed system further including a reduction unit, the captured and released CO2 from the capture unit flows into the reduction unit where it interacts with a CO2 reduction catalyst that reduces the CO2 to one or more desired product gases 34. An anode located downstream of the cathode serves as a catalyst for the oxidation of H2O and can reduce H2O to provide protons to the reduction catalyst. The oxidation of H2O by the anode results in the production of O2 as a by-product. The system advantageously spatially separates the oxidation of H2O from the reduction of CO2 by having a spacer located between the H2O oxidation catalyst (anode) and the reduction unit. This advantageously separates the O2 by-product gas stream from the product gas stream 34 to provide a high purity product gas stream.

[0038] The system of the present disclosure can be the integration of an active CO2 capture unit and a CO2 reduction unit with the flow of electrolyte on the aqueous side of the CO2 capture unit to the cathode compartment of the CO2 reduction unit.

[0039] Theoretical modelling To solve the Nernst-Planck equations for the transport of different ionic species, we developed a one-dimensional model of a water gradient membrane adjacent to an aqueous electrolyte, as seen in Figure 1B, using COMSOL Multiphysics. A time-dependent analysis was performed to look at the evolution of the concentration profiles of the species in the membrane. The carbonate-bicarbonate equilibrium reaction was set to be water-dependent, and the adjacent electrolyte was modeled as a well-mixed electrolyte with high diffusion coefficients for all species.

[0040] Species considered in the model: Based on the proposed moisture gradient mechanism for CO2 capture, the simulations considered i) CO2 as the main species for moisture gradient capture, ii) moisture content on the dry side and HO in the electrolyte adjacent to the membrane contributing to the moisture gradient, iii) H2O from the dissociation of HO, and + , iv) OH from dissociation of H2O from step 1 of the water gradient mechanism and for CO2 capture - , v) related to the equilibrium dynamics depending on the water in the membrane [ka] vi) or water-dependent equilibrium dynamics [ka] vii) K for carbonates and bicarbonates that do not contribute to the water gradient mechanism in the membrane and adjacent electrolytes + as counterions, and viii) background quaternary amines on the membrane. [ka] A total of eight types were examined.

[0041] Species transport: We assumed that only diffusion and ionic mobility due to the applied electric field drive the species transport without convection. Since the transport mechanism is driven by the water concentration, diffusion also depends on the membrane water uptake λ, which depends on the water concentration on the dry side. λ is the membrane background [ka] The governing equation used in this model is:

number

[0042] In the formula, C J is the concentration, J J is the flow velocity and R J is the reaction rate of the jth species. The total diffusivity and ion mobility fluxes are given by:

number

[0043] In the formula, D J is the λ-dependent diffusion coefficient DJ(λ), and Z J is the number of charges, and u m,j is the ionic mobility of the jth species. F is the Faraday constant and V is the electric potential. We are solving the Nernst-Planck equations, but since there is no electric potential applied to the membrane, the electroneutrality condition is imposed by:

number

[0044] Reactions in the membrane: Water gradient CO2 capture is implemented using the water-dependent carbonate-bicarbonate equilibrium reaction. H2O dissociation reactions considered in the model: [ka]

[0045] The carbonate-bicarbonate equilibrium reaction is given by: [ka]

[0046] The activity of HO in all reactions within the membrane is not considered integral,

number

[0047] Boundary conditions: On the dry side of the membrane, the inward flow rate of the CO2 feed was established as follows:

number

[0048] During the ceremony,

number

number

[0049] During the ceremony,

number

number

number

[0050] where I is the current density of CO2 utilization, and n is the number of electrons transferred to convert CO2 to CO (n=2). EXAMPLES

[0051] Example 1: Simulated capture process As the H2O concentration decreases on the non-aqueous "dry" side, the equilibrium constant also decreases, resulting in HCO3 - A continuum model using COMSOL Multiphysics software can be used to simulate the water gradient-driven CO2 capture process. The goal of these simulations is to quantify the influence of the physical properties of the AEM, such as water adsorption, water permeability, ion exchange capacity, ionic conductivity, ion selectivity, CO2 crossover, porosity, and membrane thickness, on three key performance metrics: CO2 capture efficiency (defined as the ratio of the CO2 capture flow rate to the sum of the CO2 capture flow rate and the CO2 crossover flow rate), CO2 separation efficiency (defined as the ratio of the captured CO2 concentration on the aqueous "wet" side to the CO2 concentration without CO2 crossover), and energy requirements (defined as the total energy consumed per mole of CO2 captured).

[0052] FIG. 7A shows the RH of HO and HCO3 in the membrane when the RH on the “wet” side is 100% and the RH on the “dry” side is 20%. - The pair diffusion of HCO3 - The flow rate of CO2 governs the CO2 capture flow rate. Increasing the CO2 concentration on the "wet" side increases the back-diffusion or crossing of CO2 to the "dry" side, which is shown in Figure 7B along with the pH gradient inside the membrane.

[0053] CO2 cross-loss can be minimized by directly utilizing the CO2 on the "wet" side. A calculated performance curve for the Excellion AEM is given in Figure 7C and shows that the CO2 separation efficiency decreases with increasing CO2 capture efficiency. This behavior is due to the decrease in CO2 concentration on the "wet" side and the increase in CO2 utilization flow rate, which is equal to the CO2 capture flow rate at steady state. The ideal shape of the performance curve should be rectangular such that the CO2 separation efficiency is 100% for various values ​​of CO2 capture flow rate or efficiency. This performance curve matches the CO2 utilization (conversion) efficiency of one or more suitable catalysts in the integrated system.

[0054] Furthermore, the effectiveness of the moisture gradient process for capturing CO2 from air can be experimentally evaluated. Figure 7D shows the experimentally measured pH change when air is sparged directly into 0.3 M KOH electrolyte compared to when an AEM (Excellion) is used as the contactor. The decrease in pH was found to be directly related to the increase in CO2 concentration in the electrolyte. The difference in final pH (measured after 5 hours) in both cases was >1 unit, indicating an order of magnitude higher moles of CO2 captured using the moisture gradient process.

[0055] The specific area of ​​the AEM used here is 1 cm 2 / cm 2 The rate and amount of CO capture can be substantially improved by using higher specific area configurations such as hollow fiber modules, porous carbon, or other suitable substrates.

[0056] Example 2 FTIR spectroscopy: CO3 for varying H2O concentrations in a non-aqueous solvent (CH3OH) to understand the shift in equilibrium as a function of water concentration. 2- and HCO3 - FTIR spectroscopy was performed to quantify the concentration of . The FTIR bench was equipped with a PikeVeeMaxII variable angle attenuated total reflectance (ATR) accessory and a 60 o The detector was a Bruker Invenio S equipped with a Ge face angle crystal. A mid-band liquid N2-cooled MCT detector was used and for each experiment, the spectra acquired were taken at 4 cm -1 The data was averaged over 1500 times at a resolution of 1.5 μm. - and CO3 2- At different concentrations, 1633 cm -1 HCO3 in - Band and 1450cm- 1 CO3 in 2- The intensities of the bands were individually calibrated. A custom-made 3D printed cell with a maximum volume of 4 ml was placed on top of the Ge crystal to carry out all FTIR experiments.

[0057] Initially, a known amount of NaHCO3 was dissolved in pure CH3OH and the spectrum collected showed a peak at 1633 cm -1 With its increased concentration in - The stretch bands showed an increase in intensity. CH3OH was - in its pure form and CO3 as found in aqueous systems. 2- was chosen as the solvent to prevent equilibration with HCO3 - is the known concentration of NaHCO3 dissolved in CH3OH at 1633 cm -1 Similarly, the CO3 2- is 1450cm -1 The intensity change was measured by observing the intensity change at

[0058] To study the equilibrium kinetics, a known amount of NaOH was dissolved in CHOH, CO was sparged into the system, and OH was added. - to HCO3. - The concentration of HCO3 was determined using a previously established calibration curve. A small amount of H2O was added to this solution and a spectrum was recorded to determine the - CO3 formed through decomposition 2- The same experiment was repeated with increasing amounts of HO to quantify the HO-dependent equilibrium constant (see FIG. 10A). The equilibrium of the bicarbonate decomposition reaction was also determined when the reaction was HCO3 - from CO3 2- The amount of H2O in the solution is greater than the amount added because H2O is also produced when the solution is shifted to the 0.01% range. This excess H2O was quantified by Karl-Fisher (KF) titrations.

[0059] Karl Fischer titration: A KF titration was performed to determine the HCO3 - and CO3 2-The total amount of water in a system containing NaHCO3 was determined. A custom-made 3D printed cell of the same volume as the cell used in FTIR was used for this study. A solution of CH3OH, NaHCO3, and a known amount of H2O in the cell was thoroughly mixed using a magnetic stirrer. Two Cu electrodes were placed at opposite ends of the cell to constantly monitor the open circuit potential (OCP) of the cell. 20 μl of KF titrant was periodically added to the cell and the end point was detected by a sudden increase in the OCP of the cell. This end point is an indication of the total H2O in the solution. Thus, the combination of FTIR and KF titration was used to determine the amount of HCO3 - , CO3 2- and H2O concentration can be provided, 2HCO3 - →CO2+CO3 2- The equilibrium constant for +H2O can be calculated using the following equation:

number

[0060] Where:

number

[0061] Kinetics of CO2 capture: CO2 capture experiments were carried out using a basic organic solution consisting of 1.2 M KOH dissolved in a CO2 organic binding liquid consisting of 80% ethylene glycol (EG) and 20% choline hydroxide (CH). Ethylene glycol was used as the non-aqueous solvent due to the higher solubility of KOH and its higher boiling point (~197 °C), and CH was used due to its high affinity for CO2 capture. The OH from the dissolved KOH was dissolved in CO2. - was sparged into the solution reacting with to form HCO3.

[0062] First, HCO3 -Calibration curves were obtained by measuring the variation in the resistance of organic solutions with increasing concentration. The calibration solutions were 1.2 M fixed K + Concentration and various HCO3 - / OH - The resistance of the solution was measured using electrochemical impedance spectroscopy (EIS). - shows an approximately linear change in solution resistance with increasing mole fraction of HCO3 - can be used to determine chemically adsorbed CO2 as a function of time.

[0063] An efficient gas sparger with a size of about 2 μm was used to increase the air contact with the organic solution with a volume of about 3 ml at room temperature (about 20 °C). The dynamic change in the resistance of the solution was measured using a calibration curve with HCO3 - The rate of CO2 capture can be increased by using ionic liquids with high CO2 solubility. These ionic liquids increase the dissolved concentration of molecular CO2, which in turn is converted to OH concentration. Figure 11B shows a steady increase in the moles of CO2 absorbed into the solution at an average rate of about 8.3 μmol / sec. - and increases the rate of chemical adsorption of CO2.

[0064] The amount of CO2 captured on the dry side of the unit was quantified by conversion of hydroxide to bicarbonate formation. With reference to Figure 12, it was observed that the higher the concentration of CO2 in the inlet gas, the shorter the time required to become fully saturated with bicarbonate ions.

[0065] Kinetics of CO2 transport and release: HCO3 in organic solutions under an applied electric field - HCO3 migrates towards the aqueous electrolyte, decreasing its pH over time. The electrochemical cell shown in Figure 2 was used to measure the current and pH change in the aqueous electrolyte. The CO2 release experiment was performed using chronopotentiometry, with the total current fixed at 25 mA. - was the majority charge carrier in the organic solution and the anion exchange membrane, so HCO3 -The rate of movement of is directly proportional to the current (I), so

number

number

[0066] With reference to FIG. 14, the amount of CO2 transferred over time was quantified by observing the pH drop on the wet side.

[0067] The electrochemical cell is 4 cm 2 11. Since the anion exchange membrane area was 1 μmol / s, the total rate of CO2 transport and release was about 1 μmol / s, which is about 8 times smaller than the CO2 capture rate in FIG. 11. Therefore, a maximum CO2 release rate of about 8 μmol / s can be achieved by increasing the current or membrane area by a factor of 8. The energy consumption of this process was mainly determined by the applied cell potential, which was about 6 V for the current process. It was observed that by adding ionic liquid, the applied cell potential could be substantially reduced, which also increased the CO2 capture capacity of the organic solution. It was also observed that the ionic liquid properties could be tailored to reduce the H2O uptake of the organic solution.

[0068] Table 1 shows a comparison of CO2 capture flux rates of various known materials and the materials of the present disclosure. [Table 1]

[0069] Figure 15A shows the effect of integration of both capture and reduction processes on the transport process. Improved performance resulted from the integration because there was a constant source of bicarbonate ions, as shown in Figure 15. The aqueous electrolyte used in this setup was 0.1 M KOH.

[0070] Figure 15B shows the effect of humidity on the migration process. In this test, the aqueous electrolyte was 1 M KCl and 0.1 M KHCO3. The non-aqueous capture solution was maintained at about 95°C and the simulated inlet gas was flue gas at 25°C.

[0071] Example 3: Reduction Various reduction catalysts were tested including halide-mediated Cu, microcubic Cu, and Cu mesh. Cu mesh was observed to provide the highest reduction efficiency, as shown in Figure 16. The experimental setup used is shown in Figure 5A.

[0072] A comparison of foam catalyst, #100 mesh, and #40 mesh Cu catalyst is shown in Figures 17A and 17B. The foam was found to be a wreath effect catalyst. It is believed that the pores in the foam were too small for the product gas bubbles to easily escape. The #100 mesh was found to perform better than the #40 mesh. It is believed that in the #100 mesh, the pores were large enough to allow the bubbles to continually escape, and the #100 mesh had a larger exposed surface area compared to the #40 mesh.

[0073] Example 4: Reduction efficiency The reduction efficiency of the system was tested using a cell as illustrated in FIG. 5A simulating a reduction unit according to the present disclosure. The electrolyte was a combination of KCl and KHCO3 in various volume ratios. It was observed that KCl acted as a supporting electrolyte while KHCO3 promoted the reduction of CO2, helping to achieve a higher current density. The reduction unit included a Cu mesh catalyst. The oscillating potential as described below was adjusted to determine the maximum efficiency of the reduction unit. The reduction unit was operated in a flow-through mode with electrolyte recirculation, and CO2 was flowed through the unit. Referring to FIG. 5D, a high faradaic efficiency of about 60% was obtained at a partial current of about 10 mA.

[0074] 18 and 19, an increase in current density was achieved by increasing the number of Cu meshes to provide a stack of Cu meshes, as illustrated in the reduction unit illustrated in FIG 5B, which is believed to behave like a porous electrode ensemble.

[0075] Sine wave and square wave oscillations (FIG. 20A) were tested for their effectiveness in improving selectivity. The oscillation potential reduces the depletion of CO2 concentration at the surface and 2+ Selectivity was improved by taking advantage of Cu(I) reducibility to control the selectivity. Square wave oscillation was more effective, as illustrated in Figures 20A and 20B.

[0076] Expected Examples Prospective Example 1 Performance curves for direct air capture (DAC) can be measured for state-of-the-art commercial anion exchange membranes (AEMs) (Excellion AEM, Fumatech FAA, Fujifilm, Novasep, Selemion AMV, Membrane International AMI, Tokuyama Neosepta, and Resintech AMB) for various properties: water adsorption, water permeability, ion exchange capacity, ion conductivity, ion selectivity, CO2 diffusivity, porosity, and membrane thickness.

[0077] The CO2 capture and separation efficiency can be measured by directly quantifying the water flow rate on the "dry" side and the dissolved CO2 concentration on the "wet" side using a suitable experimental setup, as shown in Figure 21, consisting of a liquid chamber (left) and a gas chamber (right) separated by an AEM. If desired, the moisture gradient within the AEM can be adjusted using a temperature-controlled dehumidifier that controls the RH and temperature of the gas chamber. The amount of CO2 captured in the electrolyte can be measured by sweeping a carrier gas through the electrolyte and quantified using gas chromatography. Alternatively, a calibration curve can be surfaced between dissolved CO2 and pH, and a pH probe can be used to indirectly measure the dissolved CO2 concentration. The H2O flow rate into the gas chamber can be measured using a humidifier at the outlet. Make-up H2O can keep the volume of the electrolyte constant.

[0078] The physical properties of the most promising AEMs can then be experimentally measured under different operating conditions with higher CO2 separation and capture efficiency. H2O and CO2 absorption isotherms, ion exchange capacity, HCO3 - The diffusion coefficients of HO, CO, and HO can be measured using a previously developed diffusion cell setup. More specifically, the ion exchange capacity of AEM can be measured using potentiometric Mohr titration, where the AEM is first titrated with Cl, if desired. - form and then activated, for example, by immersion in a 1 M KNO3 solution for 24 hours. -The amount of ions is determined by potentiometric titration with AgNO3. H2O uptake / adsorption isotherms can be determined using gravimetric analysis, where AEM first uptakes HCO3 - The mixture can be exchanged into a 5 ml flask followed by equilibration in a humidity controlled chamber for 24 hours.

[0079] HCO3 - The conductivity of the morphology of the AEM can be measured using two-probe in-plane impedance spectroscopy in a humidity controlled chamber. To measure the CO2 adsorption and diffusion coefficients, chronoamperometry can be performed in a diffusion cell with suitable electrodes on the downstream face of the AEM, where the reduction current can be recorded after CO2 is introduced on the upstream side and diffused through the AEM. The transient current density data can be fitted to Fick's second law of diffusion analysis solution to obtain the CO2 adsorption and diffusion coefficients. Diffusion coefficients and isotherms can be measured for different RH and temperatures.

[0080] In accordance with the principles herein, an AEM having a lower CO2 diffusion coefficient can have a higher CO2 separation efficiency and a higher HCO3 - The diffusion coefficient can support higher CO2 capture efficiency, and lower H2O permeability reduces the energy required to dehumidify the air. Reduction The measured physical property and the performance metric can be related to obtain a property-performance relationship for the DAC.

[0081] COMSOL simulations can then be performed using these measured physical properties to identify optimal operating conditions, such as temperature, electrolyte ionic strength, RH, air composition, air flow rate, electrolyte flow rate, CO2 pressure, and H2O flow rate, to maximize CO2 separation and capture efficiency. In other words, the simulations can be used to identify optimal operating conditions, elucidate the mechanisms of CO2 capture and transport, and provide insights for improving CO2 separation and capture efficiency based on a particular system. For example, such insights could include higher back diffusion of CO2, higher H2O flow rate, or lower HCO3 - Identify if flow rates are limiting the CO2 capture and separation efficiency. COMSOL simulations can solve mass, charge, energy, and momentum balance equations, where species transport can be described using the Nernst-Planck equation, ionic equilibria can be modeled using acid-base reactions, H2O and CO2 fractionation at the "dry" and "wet" interfaces can be defined using water adsorption and CO2 absorption isotherms, ionic Donnan equilibria can be imposed at the "wet" interface, and water-dependent CO2 capture and release reactions can be implemented at the "dry" and "wet" interfaces.

[0082] The optimal operating conditions obtained from these simulations can guide the development of CO2 capture process systems, devices, units, and processes based on the air quality and temperature of different geographic locations, so that the captured CO2 rate matches the optimal CO2 conversion rate. If the physical properties of a promising AEM are not favorable for the target CO2 capture rate, the H2O adsorption and permeability as well as the CO2 diffusion coefficient can be modified by thermal annealing to improve the CO2 capture performance. Thermal annealing is a facile route to tune the morphology and crystallinity of polymeric membranes and can be used to reduce gas and H2O permeability. An increase in the crystallinity of the matrix can result in lower CO2 solubility since gases are much more soluble in the amorphous domains. Furthermore, larger crystals can act as a barrier and increase the tortuosity of the diffusion path for gas and H2O molecules. Thermal annealing of the AEM may be performed in a suitable environment such as a vacuum oven at a specific temperature (160-200 °C) for a suitable time such as 24 hours, followed by immersion in a suitable solution such as 1 M KOH electrolyte, prior to use in the diffusion cell. Intermediate temperatures (approximately 160 °C) may favor a reduction in CO2 permeability, as very high temperatures may reduce the crystallinity of the AEM, which is required for lower CO2 permeability. In addition, higher performance of CO2 capture can be achieved by increasing the membrane interfacial area using either hollow fiber modules or porous carbon substrates.

[0083] Prophetic Example 2 Following the principles herein, a full-scale electrochemical model can be constructed in COMSOL to inform the design of an integrated CO2 capture and conversion system. Simulations can optimize prototype geometries and operating conditions to achieve maximum CO2 utilization with minimal power consumption. COMSOL simulations for the electrochemical cell described by Singh et al., "Effects of temperature and gas-liquid mass transfer on the operation of small electrochemical cells for the quantitative evaluation of CO2 reduction electrocatalysts," can be used to calculate polarization losses, species distribution, and power efficiency in a fully integrated system. The COMSOL simulations can calculate voltage losses in the catalyst layer, electrolyte, and membrane separator, which depend on (i) the dynamic loading voltage of the electrocatalyst, (ii) the conductivity and transfer number of the electrolyte and membrane, (iii) the operating conditions such as CO2 flow rate, partial pressure, and temperature, and (iv) the physical dimensions of the components. COMSOL simulations can solve the mass, charge, energy, and momentum balance equations, species transport can be described using the Nernst-Planck equation, ionic equilibrium in the electrolyte can be modeled using acid-base reactions, oxygen evolution reaction (OER) and CO2 reduction reaction (CO2RR) reactions can be described using the Butler-Volmer equation, mixing patterns in the electrolyte can be described by the Navier-Stokes equation, and CO2 capture and separation can be modeled as explained below. The total cell voltage can be calculated using the equilibrium potential E for the OER and CO2RR. 0 and dynamic charge voltage η, solution loss in electrolyte and membrane

number

number

number

[0084] Cell voltages and operating current densities can be calculated in COMSOL for prototype configurations consisting of a suitable catalytic cathode, an IrO2 anode, 0.1-1 M KOH / choline chloride hybrid electrolyte, 2-10 mm spacing between the membrane and electrodes, 0.01-0.1 mm thickness of the boundary layer, and 5-100 sccm air flow rate at ambient conditions. Optimal geometries and operating conditions can be determined and used for the design and fabrication of integrated systems.

[0085] Printing, assembly, and performance evaluation of the integrated system FIG. 8 (top) shows an initial CAD design of an exemplary electrochemical cell in which the CO2 capture unit may be integrated with an anion exchange membrane that functions as a catalytic gas diffusion electrode (GDE). If desired, the chassis may be designed in SolidWorks® and 3D printed using a Form 2 SLA 3D printer. The Form 2 printer utilizes Clear FLGPCL04 resin activated by a 405 nm laser to print optically clear parts with 150 μm lateral and 25 μm axial resolution. The resin may be chemically resistant to a wide range of solvents and pH ranges.

[0086] The 3D printed parts after cleaning can be finished by removing the support and curing under a commercial UV lamp for 20 minutes. The assembled device is shown in Figure 5 (bottom). The GDE can be made by spray coating an ink consisting of catalyst, carbon particles (to enhance electrical conductivity), and AEM ionomer (for carbon capture) on one side of a porous carbon paper (substrate and current collector). The other side of the carbon paper can be coated with only AEM ionomer if desired.

[0087] The AEM-coated side of the carbon paper is 2,On one side, the AEM ionomer can capture CO2 and on the other side, the CO2 can be converted to CO or other output. The effect of the interaction between the AEM ionomer and the catalyst on activity and selectivity can also be evaluated using a flow cell setup. Alternatively, electrospinning can be used to fabricate GDE electrodes with the same configuration and ink composition to enhance the stability of the electrode for long-term use. The relative concentration / area of ​​the AEM ionomer and catalyst can be adjusted to match the CO2 capture rate and conversion rate.

[0088] In the disclosed system, improved conversion efficiency can be obtained by utilizing a reduction catalyst and separated from the CO2 capturing AEM using a zero gap electrolyzer configuration. In this configuration, the AEM ionomer coated on the hollow fiber module can be placed close to the catalyst so that the CO2 can be captured using the hollow fiber module and transferred to the electrolyte with zero gap (<1 mm space), and the dissolved CO2 can then be converted to synthesis gas.

[0089] Chronoamperometry experiments at different applied potentials can be carried out on the fully automated integrated device to measure the production of CO and H over time (using gas chromatography) to evaluate the effectiveness of CO capture and conversion. Limiting factors such as decomposition of the AEM, agglomeration of the catalyst, or salt formation on the AEM that determine the stability and lifetime of the device can be experimentally identified and analyzed using a full-scale electrochemical model. Furthermore, after optimizing the operating conditions, the long-term performance of the integrated system (at least over 100-500 h) can be studied within the fully automated system.

[0090] The pH of the electrolyte can be varied in these chronoamperometric experiments to affect the selectivity of the CO2 reduction products, making it more selective towards other value-added products such as CH4, HCOOH, C2H5OH and the like.

[0091] In accordance with the principles herein, H2O and HCO3 in various anion exchange membranes (AEMs) are - The ionomer-catalyst pair diffusion can be customized to develop property-performance relationships for CO2 capture from air, characterize mechanistic entities for CO2 transport and conversion in integrated systems, investigate the effect of ionomer-catalyst interactions on CO2 conversion, and develop standalone and modular devices and systems that can adsorb CO2 from air, release O2 and HO, and generate industrial syngas or other products.

[0092] The technical information described herein may in some respects go beyond the disclosure of the present invention, which is exclusively defined by the appended claims. The additional technical information is provided to place the actual invention in a broader technical context and to illustrate possible related technical developments. Such additional technical information, which is not within the scope of the appended claims, is not part of the present invention.

[0093] While particular embodiments of the present invention have been shown and described in detail, it will be apparent to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects. It is therefore the object to cover all such changes and modifications that come within the true spirit and scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. The actual scope of the present invention is defined by the following claims when viewed in their proper perspective based on the prior art. Some of the embodiments of the invention related to the present invention are given below. [Embodiment 1] CO from the inlet gas 2 Active CO for capturing 2 A capture unit comprising: an inlet through which an input gas is introduced into the unit; and contacting the inlet gas to remove CO from the inlet gas; 2 and chemically absorbing the chemically sorbed CO. 2 OH - By reacting with HCO 3 - OH is arranged to convert - Non-aqueous CO containing 2 a non-aqueous region comprising a binding organic liquid; an aqueous region disposed downstream of the non-aqueous region, the HCO 3 - But, H 2 Interacts with O and CO 2 and CO 3 2- an aqueous region, HCO from the non-aqueous region to the aqueous region 3 - an anion exchange membrane disposed between the non-aqueous region and the aqueous region to facilitate diffusion and transport of a captured CO 2 and an outlet for an active CO 2 Capture unit. [Embodiment 2] 2. The active CO2 capture unit of embodiment 1, further comprising a cathode disposed upstream of the non-aqueous region and an anode disposed downstream of the aqueous region, the aqueous region comprising an aqueous electrolyte such that an electric field is adapted to be generated within the capture unit. 2 Capture unit. [Embodiment 3] 5. Non-aqueous CO 2 The active CO2 according to embodiment 1 or 2, wherein the binding organic liquid comprises an ionic liquid. 2 Capture unit. [Embodiment 4] The active CO2 according to embodiment 3, wherein the ionic liquid is imidazolium-based or phosphonium-based. 2 Capture unit. [Embodiment 5] 5. Non-aqueous CO 2 The active CO2 catalyst according to any one of the first to fourth embodiments, wherein the binding organic liquid comprises one or more ionic liquids selected from the group consisting of choline hydroxide, tetrabutylphosphonium methanesulfonate, and 1-butyl-3-methylimidazolium hexafluorophosphate. 2 Capture unit. [Embodiment 6] 5. Non-aqueous CO 2 The active CO2 according to embodiment 5, wherein the binding organic liquid comprises a non-aqueous polar organic solvent. 2 Capture unit. [Embodiment 7] The active CO2 solution of embodiment 6, wherein the non-aqueous polar organic solvent comprises one or more of an alcohol, an organic amidine base, and a guanidine base. 2 Capture unit. [Embodiment 8] 8. The active CO2 extract according to embodiment 7, wherein the organic solvent comprises one or more of ethylene glycol, methanol, and ethanol. 2 Capture unit. [Embodiment 9] The non-aqueous region is 2 9. The active CO2 according to any one of claims 1 to 8, comprising an alkali metal hydroxide dissolved in a binding organic liquid. 2 Capture unit. [Embodiment 10] 10. The active CO2 according to any one of claims 1 to 9, wherein the aqueous region comprises one or both of an aqueous electrolyte and water. 2 Capture unit. [Embodiment 11] CO from the inlet gas 2 Active CO for capturing 2 A capture unit comprising: an inlet through which an input gas is introduced into the unit; and a non-aqueous dry region into which the inlet gas is introduced; A cathode, the cathode comprising: H 2 H received from O source 2 O to H 2 and OH - and wherein the OH - is disposed upstream of the drying region so as to flow into the drying region, 2 in fluid communication with a source of OH and in fluid communication with the drying area, - interacts with the inlet gas to convert CO 2 and chemically absorbing the chemically sorbed CO. 2 OH - By reacting with HCO 3 - , and a cathode, an aqueous region containing humidified gas disposed downstream of the non-aqueous region, the HCO 3 - But, H 2 Interacts with O and CO 2 and CO 3 2- an aqueous region, HCO from the non-aqueous region to the aqueous region 3 - an anion exchange membrane disposed between the non-aqueous region and the aqueous region to facilitate diffusion and transport of an anode disposed downstream of the aqueous region; a captured CO 2 and an outlet for an active CO 2 Capture unit. [Embodiment 12] The above H 2 H produced at the cathode during the decomposition of O 2 configured to allow H to flow in a direction away from the cathode. 2 12. The activated CO2 according to embodiment 11, further comprising an outlet. 2 Capture unit. [Embodiment 13] 13. The active CO2 gas separator of embodiment 2, 11 or 12, wherein the anode is a planar and / or porous anode. 2 Capture unit. [Embodiment 14] The active CO2 cathode of embodiment 13, wherein the cathode is a porous cathode. 2 Capture unit. [Embodiment 15] 15. The active CO2 gas according to claim 13 or 14, wherein the anode is a porous anode. 2 Capture unit. [Embodiment 16] The inlet gas is anthropogenic CO 2 The active CO source according to any one of embodiments 1 to 15. 2 Capture unit. [Embodiment 17] 5. Artificial CO 2 The active CO according to embodiment 16, wherein the source is air or flue gas. 2 Capture unit. [Embodiment 18] 18. The active CO2 membrane according to any one of claims 1 to 17, wherein the anion exchange membrane comprises a hollow fiber structure. 2 Capture unit. [Embodiment 19] 19. The active CO2 membrane of any one of claims 1 to 18, wherein the anion exchange membrane comprises a quaternary amine or phosphonium attached to a polymer backbone resin with hydroxide, carbonate, and / or bicarbonate moieties. 2 Capture unit. [Embodiment 20] 20. The active CO according to embodiment 19, wherein the polymer backbone is polystyrene. 2 Capture unit. [Embodiment 21] activated CO 2 Capture and CO into product gas 2 A system for rebate, comprising: The active CO according to any one of embodiments 1 to 20 2 A capture unit; A reduction unit, the reduction unit comprising: 2 CO captured from the capture outlet 2 The activated CO 2 The reduction unit is disposed downstream of the capture unit, The captured CO 2 CO 2 a reduction unit inlet for receiving from the capture outlet, the reduction unit 2 a catalyst for reducing the captured CO 2 is arranged to flow through the reduction unit and into contact with the catalyst, and upon contact with the catalyst, the captured CO 2 But, C 2 H 4 、C 2 H 5 OH, CH 3 COOH, CH 3 OH, CH 4 、C 3 H 6 , CO and H 2 a reduction unit inlet, wherein the mixture is reduced to a product gas comprising one or more of: a CO 2 Protons for reduction and O as a by-product 2 Generate, H 2 a catalyst for the oxidation of O, the oxidation catalyst being an anode; a separator disposed between the reduction catalyst and the oxidation catalyst; An energy source. [Embodiment 22] 22. The system of embodiment 21, wherein the reduction catalyst is a copper mesh. [Embodiment 23] 23. The system of embodiment 22, wherein the copper mesh has a mesh size of about 40 to about 120 mesh. [Embodiment 24] 22. The system of embodiment 21, wherein the catalyst comprises metal nanocrystals. [Embodiment 25] 25. The system of embodiment 24, wherein the metal nanocrystals comprise Cu nanocrystals. [Embodiment 26] 26. The system of embodiment 25, wherein the Cu nanocrystals are Cu nanocubes having dominant (100) facets. [Embodiment 27] 27. The system of any one of embodiments 24-26, wherein the metallic nanocrystals are grown on a mesh substrate. [Embodiment 28] 28. The system of any one of embodiments 21-27, wherein the oxidation catalyst comprises one or more oxides of Ni, Fe-Ni, Pt-coated Ti, Ir, and Ru. [Embodiment 29] Activated CO 2 29. The system of any one of embodiments 21 to 28, wherein the capture unit and the reduction unit are spaced apart by a distance of about 5 mm to about 20 mm. [Embodiment 30] 30. The system of any one of embodiments 21-29, wherein the energy source comprises a photocell and / or an electrochemical cell. [Embodiment 31] The O gas outlet is disposed spatially separated from the outlet for the product gas. 2 31. The system of any one of embodiments 21-30, further comprising an outlet for the by-products. [Embodiment 32] The active CO according to any one of embodiments 1 to 20 2 Using a capture unit 2 A method for capturing CO 2 The OH present in the non-aqueous region is chemically adsorbed. - According to the CO 2 HCO 3 - flowing the inlet gas through the inlet and through the non-aqueous region to convert Said HCO 3 - across the anion exchange membrane and into the aqueous region, 3 - the flow of HCO into the aqueous region is driven at least in part by a water gradient across the anion exchange membrane; 3 - When the inflow of HCO 3 - is present in the aqueous region 2 Interacts with O and CO 2 and CO 3 2- To break down into, to flow, The captured CO from the aqueous region 2 At the outlet 2 and flowing the [Embodiment 33] The above H 2 O'H 2 and OH - to the cathode for decomposition into H 2 flowing O and the OH - 33. The method of embodiment 32, further comprising: flowing the aqueous solution of the present invention into the non-aqueous region. [Embodiment 34] Applying an electric field across the anion exchange membrane to induce HCO ions flowing across the anion exchange membrane. 3 - 34. The method of embodiment 32 or 33, further comprising increasing the rate of migration of. [Embodiment 35] CO 2 and using the system according to any one of embodiments 21 to 31, 3 H 6 、C 2H 4 、C 2 H 5 OH, CH 3 COOH, CH 3 OH, CH 4 , CO, and H 2 CO in the product gas, which may contain one or more of 2 A method for reducing CO 2 The OH present in the non-aqueous region is chemically adsorbed. - According to the CO 2 HCO 3 - flowing the inlet gas through the inlet and through the non-aqueous region to convert Said HCO 3 - across the anion exchange membrane and into the aqueous region, 3 - the flow of HCO into the aqueous region is driven at least in part by a water gradient across the anion exchange membrane; 3 - When the inflow of HCO 3 - is present in the aqueous region 2 Interacts with O and CO 2 and CO 3 2- and thus the captured CO 2 Bringing, shedding, The captured CO 2 from the aqueous region. 2 To flush to the outlet, The captured CO 2 5. Capture CO 2 an outlet into the reduction unit, the captured CO 2 But, C 3 H 6 、C 2 H 4 、C 2 H 5 OH, CH 3 COOH, CH 3 OH, CH 4 , CO, and H 2 and flowing the product gas comprising one or more of: and flowing the product gas to a reduction unit outlet. [Embodiment 36] 36. The method of any one of embodiments 32-35, wherein the inlet gas has a temperature of about 20-120°C. [Embodiment 37] CO from diluted sources 2 A system for capture and reduction of CO 2 A capture unit comprising: an inlet through which an input gas is introduced into the unit; and contacting the inlet gas to remove CO from the inlet gas; 2 and chemically absorbing the chemically sorbed CO. 2 OH - By reacting with HCO 3 - OH is arranged to convert - Non-aqueous CO containing 2 a non-aqueous region comprising a binding organic liquid; an aqueous region disposed downstream of the non-aqueous region, the HCO 3 - But, H 2 Interacts with O and CO 2 and CO 3 2- an aqueous region, HCO from the non-aqueous region to the aqueous region 3 - and an anion exchange membrane disposed between the non-aqueous region and the aqueous region to promote diffusion and transport of CO. 2 A capture unit; A H is disposed upstream of the capture unit and in fluid communication with the non-aqueous region of the capture unit. 2 O source inlet, H 2 Exit, and OH - an outlet for introducing OH into the non-aqueous region of the capture unit; - A cathode through which current flows; The captured CO 2 a reduction unit disposed immediately downstream of the aqueous region to receive a flow of the captured CO 2 and a product gas outlet, so that the captured CO 2 flows through the reduction unit to contact the catalyst, and upon contact with the catalyst, the captured CO 2 But, C 2 H 4 、C 2 H 5 OH, CH 3 COOH, CH 3 O.H., C. 3 H 6 , C.H. 4 , CO, and H 2 and a reduction unit that is reduced to the product gas when it flows out of the product gas outlet; downstream of the reduction unit, 2 An anode adapted to catalyze the oxidation of O and 2 The oxidation of O produces a proton for the reducing unit and O as a by-product. 2 and the anode is in fluid communication with the reduction unit to direct the protons to the reduction unit and to the product gas outlet in a spatially separated O 2 Flow to the exit, O 2 an anode for removing the a separator disposed between the reduction unit and the anode; An energy source. [Embodiment 38] 38. The system of embodiment 37, wherein the reduction catalyst is a copper mesh. [Embodiment 39] 39. The system of embodiment 38, wherein the copper mesh has a mesh size of about 40 to about 120 mesh. [Embodiment 40] 40. The system of embodiment 39, wherein the catalyst comprises metal nanocrystals. [Embodiment 41] 41. The system of embodiment 40, wherein the metal nanocrystals comprise Cu nanocrystals. [Embodiment 42] 42. The system of embodiment 41, wherein the Cu nanocrystals are Cu nanocubes having dominant (100) facets. [Embodiment 43] 43. The system of any one of embodiments 40-42, wherein the metallic nanocrystals are grown on a mesh substrate. [Embodiment 44] 44. The system of any one of embodiments 37-43, wherein the anode as a catalyst for the oxidation comprises one or more oxides of Ni, Fe-Ni, Pt-coated Ti, Ir, and Ru. [Embodiment 45] Activated CO 2 45. The system of any one of embodiments 37 to 44, wherein the capture unit and the reduction unit are spaced apart by a distance of about 5 mm to about 20 mm. [Embodiment 46] 46. ​​The system of any one of embodiments 37-45, wherein the energy source comprises a photocell and / or an electrochemical cell. [Embodiment 47] 47. The system of any one of embodiments 37-46, wherein the anode is a planar or porous anode. [Embodiment 48] 48. The system of embodiment 47, wherein the cathode is a porous cathode. [Embodiment 49] The inlet gas is anthropogenic CO 2 The system of any one of embodiments 37 to 48, which is a source. [Embodiment 50] 5. Artificial CO 2 50. The system of embodiment 49, wherein the source is air or flue gas. [Embodiment 51] 51. The system of any one of embodiments 37-50, wherein the anion exchange membrane comprises a hollow fiber structure. [Embodiment 52] 52. The system of any one of embodiments 37-51, wherein the anion exchange membrane comprises a quaternary amine or phosphonium attached to a polymer backbone resin with hydroxide, carbonate, and / or bicarbonate moieties. [Embodiment 53] 53. The system of embodiment 52, wherein the polymer backbone is polystyrene. [Embodiment 54] 54. The system of any one of embodiments 37 to 53, wherein the aqueous region comprises an aqueous electrolyte such that an electric field is adapted to be generated within the capture unit. [Embodiment 55] 5. Non-aqueous CO 2 55. The system of any one of embodiments 37-54, wherein the binding organic liquid comprises one or more ionic liquids selected from the group consisting of choline hydroxide, tetrabutylphosphonium methanesulfonate, and 1-butyl-3-methylimidazolium hexafluorophosphate. [Embodiment 56] 5. Non-aqueous CO 2 56. The system of embodiment 55, wherein the associative organic liquid comprises a non-aqueous polar organic solvent. [Embodiment 57] 57. The system of embodiment 56, wherein the organic solvent comprises one or more of ethylene glycol, methanol, and ethanol. [Embodiment 58] The non-aqueous region is 2 58. The system of any one of embodiments 37-57, comprising an alkali metal hydroxide dissolved in the binding organic liquid. [Embodiment 59] 59. The system of any one of embodiments 37-58, wherein the aqueous region comprises one or both of an aqueous electrolyte and water.

Claims

1. CO from the inflow gas ２ A CO2 capture unit for capturing an inlet through which an input gas is introduced into the unit; and contacting the inlet gas to remove CO from the inlet gas; ２ and chemically absorbing the chemically sorbed CO ２ Oh － By reacting with HCO ３ － OH － Non-aqueous CO containing ２ a non-aqueous region comprising a binding organic liquid; an aqueous region disposed downstream of the non-aqueous region, the HCO ３ － But, H ２ Interacts with O and CO ２ and CO ３ ２－ an aqueous region, HCO from the non-aqueous region to the aqueous region ３ － an anion exchange membrane disposed between the non-aqueous region and the aqueous region to facilitate diffusion and transport of A captured CO2 gas sensor disposed downstream of the aqueous region. ２ The exit, a cathode disposed upstream of the non-aqueous region; an anode disposed downstream of the aqueous region; Equipped with the aqueous region comprises an aqueous electrolyte such that an electric field is adapted to be generated within the capture unit; The non-aqueous CO 2 binding organic liquid comprises one or more ionic liquids selected from the group consisting of imidazolium-based ionic liquids, phosphonium-based ionic liquids, choline hydroxide, tetrabutylphosphonium methanesulfonate, 1-butyl-3-methylimidazolium hexafluorophosphate, alcohols, organic amidine bases, and guanidine bases. ２ Capture unit.

2. 2. The CO2 capture unit of claim 1, wherein the non-aqueous CO2-binding organic liquid comprises one or more of ethylene glycol, methanol, and ethanol.

3. The non-aqueous region is ２ 3. The CO2 capture unit of claim 1 or 2, comprising an alkali metal hydroxide dissolved in a binding organic liquid.

4. The CO2 capture unit of any one of claims 1 to 3, wherein the aqueous region comprises one or both of an aqueous electrolyte and water.

5. The cathode is H ２ H accepted from O source ２ O to H ２ and OH － and the OH － The H ２ in fluid communication with a source of O and in fluid communication with the non-aqueous region, － interacts with the inlet gas to convert CO ２ and chemically absorbing the chemically sorbed CO ２ Oh － By reacting with HCO ３ － Convert to 10. The CO2 capture unit of claim 1, wherein the aqueous region comprises humidified gas.

6. The H ２ H produced at the cathode during the decomposition of O ２ configured to allow H to flow in a direction away from the cathode. ２ The CO2 capture unit of claim 5 further comprising an outlet.

7. 7. The CO2 capture unit of claim 1, 5 or 6, wherein the anode is a planar and / or porous anode.

8. The CO2 capture unit of claim 7, wherein the cathode is a porous cathode.

9. 9. The CO2 capture unit according to claim 7 or 8, wherein the anode is a porous anode.

10. The inlet gas is anthropogenic CO ２ The CO2 capture unit according to any one of claims 1 to 9,

11. The artificial CO ２ 11. The CO2 capture unit of claim 10, wherein the source is air or flue gas.

12. The CO2 capture unit of any one of claims 1 to 11, wherein the anion exchange membrane comprises a hollow fiber structure.

13. 13. The CO2 capture unit of any one of claims 1 to 12, wherein the anion exchange membrane comprises a quaternary amine or phosphonium attached to a polymer backbone resin with hydroxide, carbonate, and / or bicarbonate moieties.

14. 14. The CO2 capture unit of claim 13, wherein the polymer backbone is polystyrene.

15. CO2 capture and CO2 to product gas ２ A system for rebate, comprising: A CO2 capture unit according to any one of claims 1 to 14, A reduction unit, the reduction unit comprising: ２ CO captured from the capture outlet ２ and the reduction unit is disposed downstream of the CO 2 capture unit to receive The captured CO ２ CO ２ a reduction unit inlet for receiving from the capture outlet, the reduction unit ２ a catalyst for reducing the captured CO ２ is arranged to flow through the reduction unit and into contact with the catalyst, and upon contact with the catalyst, the captured CO ２ But, C ２ H ４ , C ２ H ５ O.H., C.H. ３ COOH, CH ３ O.H., C.H. ４ , C ３ H ６ , CO and H ２ a reduction unit inlet, wherein the mixture is reduced to a product gas comprising one or more of: a CO ２ Protons for reduction and O as a by-product ２ Generate, H ２ a catalyst for the oxidation of O, the oxidation catalyst being an anode; a separator disposed between the reduction catalyst and the oxidation catalyst; An energy source.

16. 16. The system of claim 15, wherein the reduction catalyst is a copper mesh.

17. The system of claim 16, wherein the copper mesh has a mesh size of 40 to 120 mesh.

18. The system of claim 15 , wherein the catalyst comprises metal nanocrystals.

19. The system of claim 18 , wherein the metal nanocrystals comprise Cu nanocrystals.

20. 20. The system of claim 19, wherein the Cu nanocrystals are Cu nanocubes having dominant (100) facets.

21. The system of any one of claims 18 to 20, wherein the metal nanocrystals are grown on a mesh substrate.

22. The system of any one of claims 15 to 21, wherein the oxidation catalyst comprises one or more oxides of Ni, Fe-Ni, Pt coated Ti, Ir, and Ru.

23. 23. The system of any one of claims 15 to 22, wherein the CO2 capture unit and the reduction unit are spaced apart by a distance of between 5mm and 20mm.

24. The system of any one of claims 15 to 23, wherein the energy source comprises a photocell and / or an electrochemical cell.

25. The O gas outlet is disposed spatially separated from the outlet for the product gas. ２ The system of any one of claims 15 to 24, further comprising an outlet for the by-products.

26. The CO 2 capture unit according to any one of claims 1 to 14 is used to ２ A method for capturing CO ２ and OH present in the non-aqueous region. － The CO ２ HCO ３ － flowing the inlet gas through the inlet and through the non-aqueous region to convert The HCO ３ － across the anion exchange membrane into the aqueous region, ３ － The flow of HCO into the aqueous region is driven at least in part by a water gradient across the anion exchange membrane. ３ － When the HCO ３ － is present in the aqueous region ２ Interacts with O and CO ２ and CO ３ ２－ To break down into, to flow, The captured CO ２ The CO ２ and flushing the fluid.

27. The H ２ O.H. ２ and OH － to the cathode for decomposition into ２ Flowing O and the OH － into the non-aqueous region.

28. Applying an electric field across the anion exchange membrane to generate HCO across the anion exchange membrane. ３ － 28. The method of claim 26 or 27, further comprising increasing the rate of migration of.

29. CO ２ and using the system according to any one of claims 15 to 25, ３ H ６ , C ２ H ４ , C ２ H ５ O.H., C.H. ３ COOH, CH ３ O.H., C.H. ４ , CO, and H ２ and CO ２ A method for reducing CO ２ and OH present in the non-aqueous region. － The CO ２ HCO ３ － flowing the inlet gas through the inlet and through the non-aqueous region to convert The H.C.O. ３ － across the anion exchange membrane into the aqueous region, ３ － The flow of HCO into the aqueous region is driven at least in part by a water gradient across the anion exchange membrane. ３ － When the HCO ３ － is present in the aqueous region ２ Interacts with O and CO ２ and CO ３ ２－ thereby decomposing the captured CO ２ Bringing, shedding, The captured CO ２ from the aqueous region. ２ To flush to the outlet, The captured CO ２ The captured CO ２ an outlet into the reduction unit, the captured CO ２ But, C ３ H ６ , C ２ H ４ , C ２ H ５ O.H., C.H. ３ COOH, CH ３ O.H., C.H. ４ , CO, and H ２ and flowing the product gas comprising one or more of: and flowing the product gas to a reduction unit outlet.

30. A method according to any one of claims 26 to 29, wherein the inlet gas has a temperature of from 20 to 120°C.

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