Apparatus, system and method for converting co2 produced from municipal solid waste into fuels and useful products

Abstract

A modular, self-contained system for on-site alcohol production at municipal waste facilities integrates CO2 electrolysis and product separation into a single deployable unit. In some embodiments, the system can employ a three-compartment CO2 electrolyzer that in some cases exhibits higher alcohol production rates and reduced CO2 crossover. In some embodiments, the plug-and-play nature of the system can enable simplified installation and operation at a variety of waste management sites. In certain implementations, the integrated design can improve overall efficiency by consolidating multiple process steps into a unified system.

Description

[0001] Government Interest Statement

[0002] This invention was made with the support of the U.S. government, at least in part, under U.S. Department of Energy grant number DE-SC0021472. The government holds certain rights to this invention.

[0003] Cross-references to related applications

[0004] This application relates to and claims priority to U.S. Provisional Patent Application Serial No. 63 / 568,185, filed March 21, 2024, entitled “Apparatus, System, and Method for Converting CO2 from Municipal Solid Waste into Fuel and Useful Products.” Application 63 / 568,185 is incorporated herein by reference in its entirety. Technical Field

[0005] The field of this invention is electrochemistry. The described apparatus, systems, and methods relate to processes for the electrochemical reduction of CO2 into fuels and useful products. Background Technology

[0006] Recycling the resulting carbon dioxide back into fuels and useful chemicals is beginning to impact the U.S. economy. Currently, fuels and organic chemicals are still typically made from fossil fuels such as oil, coal, and / or natural gas. However, increasing the amount of these fuels and chemicals made from recycled CO2 will reduce U.S. dependence on imported oil. Furthermore, because CO2 produced at power plants is transformed from waste into a useful and economically viable feedstock, greenhouse gas emissions contributing to climate change will also decrease.

[0007] The United States has made the deployment of systems and facilities for generating renewable fuels a key priority. The economic benefits associated with renewable fuel production are also substantial. The U.S. Department of Energy has created a $10,000,000 annual consortium called “Reduction and Upgrading for e-Fuels (CO2Rue)”, with the goal of developing technologies to convert waste CO2 from ethanol biorefineries into sustainable aviation fuel (SAF).

[0008] If the U.S. is to begin meeting its fuel needs (including aviation fuels) through recycled CO2, additional renewable CO2 sources will be required. According to a recent report, municipal solid waste contains enough carbon to meet several times the aviation industry's needs. Unfortunately, the sources are fragmented. No single source can produce enough CO2 to supply the U.S.'s required 25,000,000 gallons / year of SAF.

[0009] In recent years, driven by the urgent need to address climate change and develop sustainable energy, the field of converting CO2 into high-value products has made rapid progress. Researchers have explored various methods, including electrochemical, thermochemical, and biological approaches, to efficiently convert CO2 into fuels and chemicals.

[0010] In particular, electrochemical CO2 reduction has attracted considerable attention due to its high selectivity and potential compatibility with renewable power sources. This approach typically involves the use of a cathode and an anode, where CO2 is reduced to form products such as carbon monoxide, formic acid, ethylene, or alcohols, and water is oxidized at the anode to produce oxygen and protons. The selection of catalyst materials, electrolyte composition, and operating conditions plays a crucial role in determining the product distribution and overall efficiency of the process.

[0011] Previous work in this field has made significant progress in CO2 conversion technology. For example, U.S. Patent No. 9,181,625, entitled "Apparatus and Method for Converting Carbon Dioxide into Useful Fuels and Chemicals," discloses a catalyst layer for CO2 conversion in an electrochemical electrolyzer. Patent '625 teaches the use of catalyst layers that exhibit improved CO2 reduction efficiency and selectivity for desired products such as carbon monoxide.

[0012] Additionally, U.S. Patent No. 10,280,378, entitled "Systems and Methods for the Production of Renewable Fuels and Chemicals," describes systems and methods for simultaneously capturing CO2 and converting it into high-value products. The integrated CO2 capture and conversion approach described in U.S. Patent No. 10,280,378 represents an important direction in process intensification for CO2 utilization. By combining the capture and conversion steps, such systems can reduce energy requirements and equipment costs. This concept has been further explored in various configurations, including the use of bipolar films, gas diffusion electrodes, and microfluidic devices.

[0013] In addition to the catalysts described in U.S. Patent No. 9,181,625, researchers have investigated a wide variety of materials for the electroreduction of CO2. These include other transition metals, alloys, metal oxides, and molecularly engineered catalysts. For example, copper-based catalysts show promise for producing multi-carbon products such as ethanol, while silver and gold catalysts are commonly used for selective CO production. Ongoing research aims to develop catalysts with improved activity, selectivity, and stability under industrially relevant conditions.

[0014] The full contents of U.S. Patent Nos. 9,181,625 and 10,280,378 are incorporated herein by reference.

[0015] While a significant amount of work has been dedicated to developing catalysts for the electrochemical reduction of CO2 to alcohols, the development of membranes exhibiting both high ionic conductivity and low alcohol crossover remains a persistent challenge. Many researchers have striven to create membranes that demonstrate these desired properties, but with limited success. This is primarily attributed to the inherent difficulty in decoupling anion transport from alcohol transport, as both substances cross the membrane in the same direction. Consequently, improvements in ionic conductivity often lead to a corresponding increase in alcohol crossover, resulting in reduced product selectivity and overall system efficiency.

[0016] The challenges in developing membranes for CO2 electroreduction systems extend beyond the trade-off between ion conductivity and alcohol crosstalk. Researchers are also investigating ways to enhance CO2 transport to the catalyst surface, improve mechanical and chemical stability under operating conditions, and reduce membrane fouling. Novel membrane materials being explored include composite membranes containing inorganic fillers, block copolymers with customized hydrophilic and hydrophobic domains, and chemically modified commercial membranes.

[0017] Using municipal solid waste (MSW) as a CO2 source for fuel production presents unique challenges and opportunities. MSW typically contains a mixture of organic and inorganic materials, requiring efficient sorting and processing technologies to separate carbon-rich fractions. Technologies for waste gasification and pyrolysis are being developed to convert MSW into syngas (CO and H2), which can then be used as a feedstock for fuel synthesis. Alternatively, anaerobic digestion of organic waste can produce biogas containing significant amounts of CO2 that can be captured and converted.

[0018] The decentralized nature of MSW (Multi-Site Wastewater) sources necessitates the development of modular, scalable CO2 conversion systems that can be deployed at various scales. Such systems must be robust, easy to operate, and capable of handling the inherent volatility in the feedstock composition of CO2 derived from MSWs. Furthermore, integrating these systems with existing waste management infrastructure and local energy grids presents both technical and logistical challenges.

[0019] As research into CO2 conversion technologies progresses, there is a growing focus on system-level optimization and lifecycle assessment to ensure that developed processes result in net reductions in greenhouse gas emissions and are economically viable. This holistic approach considers numerous factors across the entire production chain, from CO2 capture to final fuel use, such as energy inputs, material requirements, and potential environmental impacts. Summary of the Invention

[0020] In some implementations, a modular, self-contained, and plug-and-play system for converting CO2 into alcohol products may include a CO2 electrolysis unit, a product separation unit, and a balance of plant.

[0021] In some embodiments, the CO2 electrolysis device may include multiple compartments and membranes. The electrolysis device may include a cathode compartment, an anion exchange membrane, a central compartment, a cation exchange membrane, and an anode compartment.

[0022] In some embodiments, the cathode compartment may include a cathode flow field, a cathode gas diffusion layer, and a cathode catalyst layer. In some embodiments, the cathode flow field may have a serpentine channel formed by machining in a stainless steel plate. The cathode catalyst layer may include copper-based nanostructures, such as nanoparticles, nanosheets, or nanocubes, which are coated onto the cathode gas diffusion layer and configured to convert CO2 into alcohols.

[0023] In some embodiments, the central compartment may be located between the anion exchange membrane adjacent to the cathode compartment and the cation exchange membrane adjacent to the anode compartment. In some aspects, the central compartment may include an ion exchange medium. In some embodiments, the ion exchange medium may include cation exchange resin, anion exchange resin beads, cation exchange fiber mat, and / or anion exchange fiber mat. In some embodiments, the thickness of the ion exchange medium may be about 2 mm.

[0024] In some embodiments, the anion exchange membrane may contain a benzyl group combined with at least one of the following: imidazolium, pyridinium, pyrazolium, pyrrolidineonium, pyrroloinium, pyrimidineonium, piperidinium, indoleonium, triazineonium, phosphonium, or quaternary ammonium. In some embodiments, the anion exchange membrane may contain inorganic fillers, organic fillers, and / or barrier layers.

[0025] In some embodiments, the cation exchange membrane may be a Nafion membrane with a thickness of less than 400 μm.

[0026] In some embodiments, the anode compartment may include an anode flow field, an anode gas diffusion layer, and an anode catalyst layer. In some aspects, the anode flow field may have a serpentine channel formed by machining in a titanium plate. The anode catalyst layer may comprise a Pt / C and / or Pt alloy nanoparticle catalyst coated onto the anode gas diffusion layer, the Pt / C and / or Pt alloy nanoparticle catalyst being configured for oxidizing H2 and reducing the electrolytic cell voltage.

[0027] In some embodiments, the product separation unit of the system may include a condenser. The condenser can separate the alcohol product from unreacted H2 and / or CO2, which can then be recycled to feed the CO2 electrolysis unit.

[0028] In some respects, the supporting infrastructure may include a safety system that triggers automatic system shutdown in the event of operational problems. This can help ensure the safe and reliable operation of the modular system.

[0029] In some implementations, the modular, self-contained nature of the system allows for easy installation and operation in various locations. Integrated design can combine multiple process steps into a unified system, potentially improving the overall efficiency of CO2 conversion to alcohol products.

[0030] In some embodiments, the central compartment is located between the anion exchange membrane of the cathode in the cathode compartment and the cation exchange membrane of the anode in the anode compartment.

[0031] In some embodiments, CO2 is reduced to alcohol at the Cu cathode and reacts with the generated OH-. - The reaction forms carbonate / bicarbonate ions, and some alcohols cross the anion exchange membrane into the central compartment.

[0032] In some implementations, the anion exchange membrane electrolysis unit (AEM) features high conductivity and high alcohol crosstalk.

[0033] In some embodiments, the central compartment is used to regenerate CO2 from cross-flowing carbonate / bicarbonate, collect cross-flowing alcohols, and / or further reduce alcohol cross-flow to the anode.

[0034] In some embodiments, the cation exchange membrane (CEM) is placed against the anode and blocks the transport of carbonate / bicarbonate ions to the anode, thereby promoting the transport of protons from the anode to the central compartment.

[0035] In some implementations, hydroxide is precipitated instead of oxygen at the Pt / C anode, thereby reducing the electrolytic cell voltage. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of a process for converting CO2 from sources such as municipal waste into liquid products (which can be converted into SAF).

[0037] Figure 2 This is a schematic diagram of an electrolysis device.

[0038] Figure 3 It is a graph showing the properties of various membranes. Detailed Implementation

[0039] It should be understood that the processes described herein are not limited to the specific methods, schemes, and reagents described herein, as these can be modified, as will be recognized by those skilled in the art. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the processes. It should also be noted that, as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural references unless the context explicitly specifies otherwise. Thus, for example, reference to “a connector” refers to one or more connectors and their equivalents known to those skilled in the art. Similarly, the phrase “and / or” is used to indicate that one or both of the described situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0040] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the described processes pertain. Embodiments of the processes, along with their various features and advantageous details, are explained more fully with reference to non-limiting embodiments and / or detailed in the following description. It should be noted that, as those skilled in the art will recognize, a feature of one embodiment may be used in conjunction with other embodiments, even if not explicitly stated herein.

[0041] Any numerical range described herein includes all values ​​from the lower limit to the upper limit in increments of one unit, provided that there is an interval of at least two units between any lower limit and any upper limit. As an example, if the concentration of a component or the value of a process variable (such as size, angle, pressure, time, etc.) is stated as, for example, 1 to 98, specifically 20 to 80, more specifically 30 to 70, then this means that values ​​such as 15 to 85, 22 to 68, 43 to 51, 30 to 32, etc., are explicitly listed in this specification. For values ​​less than 1, a unit is considered to be 0.0001, 0.001, 0.01, or 0.1, as appropriate. These are merely examples of specific intent, and all possible combinations of values ​​between the minimum and maximum values ​​should be treated similarly.

[0042] Furthermore, a "Definitions" section follows, which specifically defines the particular terms associated with the process. Specific methods, apparatus, and materials are described, although methods and materials similar to or equivalent to those described herein may be used to implement or test the process.

[0043] definition

[0044] As used herein, the term "polymer electrolyte membrane" refers to both cation exchange membranes (which typically contain polymers with multiple covalently linked negatively charged groups) and anion exchange membranes (which typically contain polymers with multiple covalently linked positively charged groups). Typical cation exchange membranes include proton-conducting membranes, such as perfluorosulfonic acid polymers available under the trade name NAFION® from EI du Pont de Nemours and Company (DuPont), Wilmington, DE.

[0045] As used herein, the terms "anion exchange membrane electrolysis device" or "AEM electrolysis device" refer to an electrolysis device having an anion-conducting polymer electrolyte membrane that separates the anode and cathode.

[0046] As used in this article, the term "MEA" refers to a membrane electrode assembly.

[0047] Detailed description

[0048] A distributed system for the production of sustainable aviation fuel (SAF) may include: converting CO2 derived from municipal waste into an alcohol solution, such as ethanol or isopropanol, on-site; and then transporting the alcohol solution to a centralized facility for conversion into SAF.

[0049] Figure 1 A flowchart of an exemplary on-site conversion system 1000 for producing alcohols from CO2 is shown. In some embodiments, the CO2 source is a municipal waste facility. In at least some embodiments, the conversion system 1000 may be self-contained and plug-and-play, enabling operators unfamiliar with chemical processes to operate the conversion system 1000.

[0050] In at least some embodiments, the conversion system 1000 eliminates the need for distillation systems that take hours to get up and are susceptible to process interruptions. In some embodiments, a single unit can simultaneously handle electrolysis for alcohol formation and separation for alcohol concentration. In at least some embodiments, automated skid-mounted equipment with safety systems surrounding the unit can automatically shut down the system if needed, such as during a system failure.

[0051] The conversion system 1000 may include multiple components to facilitate an efficient and controlled conversion process:

[0052] Figure 1 A conversion system 1000 for processing and converting CO2 and H2 feeds is shown.

[0053] In some embodiments, the conversion system 1000 includes an electrolysis unit 150 having an anode 152 and a cathode 154, configured to process the input feed. In at least some embodiments, the electrolysis unit 150 is the site of the primary electrochemical conversion of CO2. In some embodiments, at the cathode 154, CO2 is reduced to form alcohol products, while the anode 152 promotes the oxidation of water or hydrogen to provide the electrons required for the reduction reaction. In some embodiments, the electrolysis unit 150 employs specialized catalysts and membrane technologies to improve conversion efficiency and selectivity.

[0054] In some embodiments, the conversion system 1000 includes a humidifier 122 and / or a humidifier 124. In some embodiments, the humidifier 122 and / or humidifier 124 can be used to control the moisture content in the gas feeds D and E. In some embodiments (e.g.) Figure 1 In the embodiment shown, the humidifier 122 can be responsible for adjusting the humidity of the incoming H2 stream. In some embodiments (e.g.) Figure 1 In the embodiment shown, the humidifier 124 can be used to adjust the humidity of the incoming CO2 feed and / or to regulate the recirculated gas.

[0055] In some embodiments, the conversion system 1000 includes condensers 112, 114, and / or 116 arranged in different sections of the process flow. In at least some embodiments, these condensers function in product separation and purification. For example, in some embodiments, condenser 112 may be responsible for cooling and condensing product stream A exiting the electrolysis unit 150. In some embodiments, this product stream may contain isopropanol that can be separated in condenser 112. In at least some embodiments, product stream A contains isopropanol and unreacted H2.

[0056] In some embodiments, condenser 114 may be used to cool and condense product stream B exiting electrolysis unit 150. In some embodiments, product stream B may contain isopropanol that can be separated in condenser 114. In at least some embodiments, product stream B contains isopropanol and unreacted CO2.

[0057] In some embodiments, evaporator 140 can be used to separate CO2 and alcohol from electrolyte stream C. In some embodiments, product stream C may contain isopropanol, which can be separated in condenser 116. In at least some embodiments, product stream C contains CO2 and isopropanol.

[0058] In some embodiments, condensers 112, 114 and / or 116 are arranged to handle different parts of the flowing material, and cooling water connections for temperature management are shown.

[0059] In some embodiments, the conversion system 1000 includes several pumps 160 arranged in different locations to facilitate fluid movement through the system and / or maintain proper circulation of reactants and products. In some embodiments, these pumps ensure consistent flow rates, which can be crucial for maintaining optimal reaction conditions and separation efficiency.

[0060] In some embodiments, the conversion system 1000 includes a heat exchanger 132 integrated into the process flow, which removes waste heat generated by the electrolysis unit 150 and enables temperature control and energy recovery within the system. In some embodiments, the heat exchanger 132 may help to preheat the incoming feeds D and E using the departing product stream, thereby improving overall energy efficiency.

[0061] In some embodiments, the conversion system 1000 includes a cooling water loop connected to a condenser, thereby providing temperature control for efficient separation and purification. In some embodiments, condenser temperature management is crucial for achieving desired product specifications and / or maximizing recovery. In some embodiments, the conversion system 1000 has a CO2 feed stream D and an H2 feed stream E entering the system. In some embodiments, a purge stream is provided at certain locations. In some embodiments, the electrolyte is recirculated. In some embodiments, this ensures a continuous and stable water supply to support ion conduction within the membrane and redox reactions at the electrodes.

[0062] In some implementations, CO2 and H2 are the primary reactants of the conversion system 1000. In some implementations, CO2 is derived from municipal waste facilities, while H2 is generated on-site via water electrolysis and / or originates externally.

[0063] In some embodiments, the conversion system 1000 includes purge streams F at different locations. In some embodiments, the purge streams F remove unwanted byproducts or maintain system purity by preventing the accumulation of inert gases or contaminants.

[0064] In some embodiments, the system integrates the processing of feed material through the electrolysis unit components (anode 152 and cathode 154) while maintaining appropriate temperature and flow control via heat exchanger 132 and pump 160. In some embodiments, the system includes separation capabilities for processing the output stream into desired products.

[0065] In some implementations, the conversion system 1000 is powered by a power source 180. In some implementations, the power source 180 is a renewable energy source, such as solar panels or a wind turbine. Utilizing renewable resources to power the conversion system 1000 aligns with the system's objective of establishing a sustainable process for converting waste CO2 into high-value products, thus potentially enabling carbon-neutral or even carbon-negative fuel production when considering the entire life cycle of the process.

[0066] In some implementations, depending on the specific catalyst used and the operating conditions, the conversion system 1000 can be configured to produce ethanol or isopropanol and other products.

[0067] The process of chemical conversion using electrochemical electrolytic cells has been known for many years. Typically, an electrochemical electrolytic cell comprises an anode, a cathode, and an electrolyte. A catalyst can be placed on the anode, cathode, and / or in the electrolyte to promote the desired chemical reaction. During operation, reactants or a solution containing reactants is fed into the electrolytic cell. A voltage is then applied between the anode and cathode to promote the desired electrochemical reaction.

[0068] When using an electrochemical electrolyzer as a CO2 conversion system, reactants containing CO2, carbonates, or bicarbonates are fed into the electrolyzer. A voltage is applied to the electrolyzer, and the CO2 reacts to form new compounds.

[0069] Figure 2 An embodiment of an electrolysis device 2000 for converting CO2 into alcohols is shown. In some embodiments, the electrolysis device 2000 includes: a cathode compartment 220 comprising a cathode flow field 200, a gas diffusion layer 201, and a cathode catalyst layer 202; an anion exchange membrane 203; a central compartment 204 comprising a porous ion exchange medium; a cation exchange membrane 205; and an anode compartment 230 comprising an anode catalyst layer 206, a gas diffusion layer 207, and an anode flow field 208.

[0070] In some embodiments, the electrolysis device 2000 is (at least in part) constructed using 5 cm³ Dioxide Materials with a three-compartment design. 2 The hardware of a formic acid electrolysis unit is formed. A typical three-compartment design includes a cathode compartment, a central compartment, and an anode compartment.

[0071] In some embodiments, the cathode flow field 200 is a serpentine flow field. In some embodiments, the anode flow field 208 is a serpentine flow field.

[0072] In some embodiments, catalyst layer 201 is a copper-based catalyst for converting CO2 into alcohols.

[0073] In some implementations, the copper-based catalyst layer is prepared using products such as, but not limited to, copper and copper alloy nanoparticles, nanocubes, or nanosheets as catalysts.

[0074] In some embodiments, catalyst layer 206 is a Pt / C catalyst layer for hydrogen oxidation to reduce the electrolyzer voltage and prevent cross-flowing alcohols (if present) from being oxidized.

[0075] In some embodiments, the anion exchange membrane 203 is a Sustainion® anion membrane manufactured by Dioxide Materials or a PiperION membrane manufactured by Versogen. ® Or Aemion manufactured by Ionomr ® wait.

[0076] In some embodiments, the cation exchange membrane 205 is a perfluorosulfonic acid (PFSA) membrane or a hydrocarbon sulfonic acid (PFSA-free) membrane, such as, but not limited to, Nafion membranes manufactured by Ionomr. ® or Pemion ® membrane.

[0077] In some embodiments, the cathode flow field receives a feed of moistened CO2 gas, which is electrochemically reduced to an alcohol at the gas diffusion electrode (GDE) cathode catalyst layer 202, thereby generating OH. - The OH - It reacts with CO2 to form carbonate / bicarbonate ions. In some embodiments, the alcohol is separated from the cathode exhaust and collected for SAF production.

[0078] In at least some embodiments, the ion exchange medium comprises a cation exchange medium and / or anion exchange resin beads. In at least some embodiments, the ion exchange medium is a strong acid cation medium that is continuously subjected to hydrogen ions (H+). + ) acidification, hydrogen ions (H + It is formed at the anode and transported from the anode through the cation exchange membrane. In some embodiments, the ion exchange medium includes ion exchange resin packing, such as, but not limited to, AmberLite. TM Resin and / or Dowex ® Resin.

[0079] In at least some embodiments, carbonate / bicarbonate ions generated at the cathode and transported through the anion exchange membrane 203 are prevented from further transport to the anode due to the cation exchange membrane. Alternatively, in at least some embodiments, they decompose within the acidified ion exchange medium to produce CO2. In some embodiments, this CO2 is separated together with any alcohols transported through the anion exchange membrane and recycled to the feed cathode. In some embodiments, the alcohols are collected as products for further conversion to SAF. In at least some embodiments, the ion exchange medium reduces (if not eliminated) CO2 and alcohol crosstalk.

[0080] In some implementations, a CEM with a thickness preferably of 400 μm, more preferably less than 200 μm, or even more preferably less than 100 μm is used to reduce the total resistance of the electrolytic cell, thereby improving energy efficiency.

[0081] In at least some embodiments, a cation exchange medium with a thickness preferably less than 2 mm, more preferably less than 1 mm, or even more preferably less than 0.5 mm is used to reduce the total resistance of the electrolytic cell.

[0082] Figure 3 Key performance characteristics of various membranes used in the electrolysis apparatus 150 are illustrated. In some embodiments, the membrane contains a benzyl group in combination with at least one of the following: imidazolium, pyridinium, pyrazolium, pyrrolidineonium, pyrroloinium, pyrimidineonium, piperidinium, indoleonium, triazineonium, phosphonium, or quaternary ammonium.

[0083] In some implementations, the membrane is crosslinked with, for example (but not limited to), tetramethylhexanediamine (TMHDA).

[0084] In at least some embodiments, the membrane comprises a filler that is an inorganic or organic filler, such as, but not limited to, TiO2, ZrO2, graphene, graphene oxide, PTFE, or polyvinyl chloride (PVC).

[0085] In at least some embodiments, the membrane includes a barrier layer sandwiched in the middle of the membrane, such as, but not limited to, clay, TiO2, ZrO2, or MCM-41. Specific Implementation Example 1

[0087] In Specific Example 1, anion exchange membranes with different ligands were synthesized using the same procedure disclosed in U.S. Patent No. 9,849,450 (which is incorporated herein by reference), such as, but not limited to, tetramethylimidazolium (TMIM), trimethylamine (TMA), methylpiperidine (MPi), 3,5-dimethylpyridine (DMP), and N-methylpyrrolidine (MPy). The membranes were crosslinked using tetramethylhexamethylenediamine (TMHDA). The polymer solution was cast onto a polyethylene terephthalate (PET) liner. All membranes prepared above were activated by immersion in a 1M KOH solution.

[0088] Ethanol crosstalk was performed using an H-type electrolyzer. A candidate membrane was placed between two chambers, and then 1M ethanol and DI water were added to each chamber of the H-type electrolyzer. The change in ethanol accumulation in the water chamber over time was measured using nuclear magnetic resonance (NMR). Ethanol permeability is listed in Table 1.

[0089] Area specific resistance (ASR) was measured in an electrochemical electrolytic cell using a potentiostat (Solartron, 1276) coupled to a frequency response analyzer (FRA, Solartron 1255). A membrane was sandwiched between a Pt cathode and an IrO2 anode loaded on carbon fiber paper and mounted at a depth of 5 cm. 2 In the electrolysis device hardware of DioxideMaterials, 1M K₂CO₃ is fed to the cathode and anode. The electrolytic cell is maintained at room temperature. Electrochemical impedance spectroscopy (EIS) is measured at an open-circuit potential with a scan frequency from 100 kHz to 1 Hz at an amplitude of 10 mV. The membrane resistance (R) is determined by the intercept of the EIS on the real axis, assuming that the contributions of the electrolytic cell hardware and electrodes are negligible. ASR is calculated by the following formula:

[0090]

[0091] Where R is the membrane resistance and A is the geometric area of ​​the membrane in contact with the electrode.

[0092] To evaluate the effectiveness of crosslinking agents on membrane performance, an influence factor (IF) on membrane performance (specifically, for areal resistivity (ASR) and permeability (p)) is introduced, and defined as follows:

[0093]

[0094] Where ASR0 and p0 are the area resistivity and permeability of the original Sustainion® membrane functionalized with ligand tetramethylimidazolium (TMIM), respectively, and x refers to the membrane with other ligands.

[0095] Table 1: Properties of membranes with different ligands.

[0096]

[0098] Table 1 shows the properties of membranes with different ligands. X-TMIM and X-MPy membranes show IFs of 2 and 1.5, respectively, which are higher than 1, indicating a positive effect of the crosslinking agent on both membranes. X-TMA and X-DMP membranes have IFs close to 1, so the crosslinking agent has no significant effect. However, X-MPi shows a much smaller IF of 0.4, indicating a negative effect of the crosslinking agent. Specific Implementation Example 2

[0100] In Specific Example 2, various ligands with different pKa were selected to replace TMIM in the Sustainion® anion exchange membrane to adjust conductivity and alcohol crosstalk. The polymer solution was cast onto a PET liner. All membranes prepared above were activated by immersion in a 1M KOH solution.

[0101] The areal resistivity and permeability were measured. Table 2 shows the ethanol permeability and ASR of membranes with different ligands.

[0102] Table 2: Ethanol permeability and ASR of membranes with different ligands.

[0103] Specific Implementation Example 3

[0105] In Specific Example 3, inorganic fillers were introduced into the original Sustainion® X-37 to regulate ethanol crosstalk. TiO2 (18nm), ZrO2 (<100nm) powder, graphene oxide, and graphene nanosheets were mixed with a polymer solution. The filler content was 0-20%. The mixture was cast onto a PET pad. All membranes prepared above were activated by immersion in a 1M KOH solution. The areal resistivity and permeability were measured. The simultaneous addition of graphene oxide and graphene nanosheet components not only reduced the ethanol permeability from 1.5 × 10⁻⁶, but also... -7 mol / cm 2 / sec decreased to 4.16×10 -8 mol / cm 2 / sec, and reduced ASR from 0.26 Ωcm 2 Reduced to 0.1 Ωcm 2 . Specific Implementation Example 4

[0107] In Specific Example 4, a hydrophobic polyvinyl chloride (PVC) polymer was blended into a Sustainion® membrane. First, PVC was dissolved in dimethylacetamide (DMAC), and a homogenizer was used to mix a certain amount of the PVC solution with the polymer solution to obtain a homogeneous solution. This solution was then cast onto a PET pad and dried in an oven to form a membrane. Prior to testing, the membrane was activated in 1M KOH.

[0108] As the PVC concentration in the membrane increases, the permeability decreases to 5.18 × 10⁻⁶. -8 mol / cm 2 / sec, and up to 20% PVC, the ASR remained very close to that of the original membrane. However, with the addition of 50% PVC, the ASR increased significantly to 0.584 Ωcm. 2 . Specific Implementation Example 5

[0110] In Specific Example 5, a barrier layer was introduced. The barrier layer comprised molecular sieves, a clay layer, graphene, graphene oxide, and polytetrafluoroethylene (PTFE) particles. The sandwich-type barrier layer was prepared as follows: a suspension with different fillers was prepared by ultrasonically mixing the fillers in 10 ml of a polymer solution to obtain a 5% by weight suspension. A film of the Sustainion® 37 solution was cast onto a polypropylene backing and dried at room temperature for 30 minutes to obtain a 15 μm thick film. Then, a 20 μm thick suspension containing fillers was cast onto the Sustainion® 37 film and dried at room temperature for 30 minutes. Finally, another 20 μm thick Sustainion® 37 film was cast onto this film.

[0111] Measure the area resistivity and permeability. The permeability decreases by an order of magnitude, to 4-7 × 10⁻⁶. -8 mol / cm 2 / sec.

[0112] Although specific elements, embodiments, and applications of the invention have been shown and described, it is to be understood that the invention is not limited thereto, as improvements can be made by those skilled in the art without departing from the scope of this disclosure, particularly in light of the foregoing teachings.

Claims

1. A system comprising: CO2 electrolysis unit; and Product separation unit.

2. The system according to claim 1, wherein the CO2 electrolysis device comprises: Cathode compartment; Anion exchange membrane; Central compartment; Cation exchange membrane; and Anode compartment.

3. The system according to claim 2, wherein the cathode compartment comprises: Cathode flow field; Cathode gas diffusion layer; and Cathode catalyst layer.

4. The system according to claim 3, wherein the cathode flow field has a serpentine channel formed by machining in a stainless steel plate.

5. The system of claim 3, wherein the cathode catalyst layer comprises a copper-based nanostructure selected from the group consisting of nanoparticles, nanosheets, and nanocubes, the copper-based nanostructure being coated onto the cathode gas diffusion layer and configured to convert CO2 into alcohol.

6. The system of claim 2, wherein the central compartment is located between the following: The anion exchange membrane adjacent to the cathode compartment; and The cation exchange membrane adjacent to the anode compartment.

7. The system of claim 2, wherein the anion exchange membrane comprises a benzyl group in combination with at least one of the following: imidazolium, pyridinium, pyrazolium, pyrrolidineium, pyrroloinium, pyrimidineium, piperidinium, indoleium, triazineium, phosphonium, or quaternary ammonium.

8. The system according to claim 2, wherein the anion exchange membrane comprises inorganic filler, organic filler and / or a barrier layer.

9. The system of claim 2, wherein the central compartment comprises an ion exchange medium.

10. The system according to claim 9, wherein the ion exchange medium comprises cation exchange resin, anion exchange resin beads, cation exchange fiber mat and / or anion exchange fiber mat.

11. The system according to claim 9, wherein the thickness of the ion exchange medium is 2 mm.

12. The system of claim 2, wherein the cation exchange membrane is a Nafion membrane with a thickness of less than 400 μm.

13. The system of claim 2, wherein the anode compartment comprises: Anode flow field; Anode gas diffusion layer; and Anode catalyst layer.

14. The system of claim 13, wherein the anode flow field has a serpentine channel formed by machining in the titanium plate.

15. The system of claim 13, wherein the anode catalyst layer comprises a Pt / C and / or Pt alloy nanoparticle catalyst coated onto the anode gas diffusion layer, the Pt / C and / or Pt alloy nanoparticle catalyst being configured for oxidizing H2 and reducing the electrolytic cell voltage.

16. The system of claim 1, wherein the product separation unit comprises a condenser.

17. The system of claim 16, wherein the condenser separates the alcohol product from unreacted H2 and / or CO2, and then recycles the unreacted H2 and / or CO2 to feed the CO2 electrolysis unit.

18. The system of claim 1, wherein the system is modular.

19. A method for producing alcohols from CO2 using an electrolysis device.

20. A system comprising an electrolysis device for producing fuel from CO2.

21. An electrolysis apparatus.

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