Continuous Direct Air Capture and Electrochemical Conversion of CO2 and H2O into Ethylene and Oxygen in Solid Electrolyte Reactor

Abstract

Direct air capture (DAC) and conversion of carbon dioxide into valuable chemicals is an eco-sustainable solution to curb the urgent climate crisis. This application demonstrates a practical and scalable solid electrolyte electrochemical cell that can directly uptake CO2 and H2O from air and continuously convert them into basic petrochemical ethylene and oxygen with extremely low voltage potential of 0.6 V and 1 A current. This DAC solid electrolyte reactor can produce approximate 70 milli gram ethylene in 1 hour, about 80% energy efficiency and remain in lower temperature.

Description

CROSS-REFERENCED APPLICATIONS

[0001] This application is a continuation of U.S. application Ser. No. 18 / 398,125 entitled “Continuous Direct Air Capture and Electrochemical Conversion of CO2 and H2O into Ethylene and Oxygen in Solid Electrolyte Reactor” filed Dec. 27, 2023, the disclosure of which is incorporated by reference in its entirety.GOVERNMENT RIGHTS STATEMENT

[0002] This invention was made with government support under the Grant Number 80NSSC22PB070 awarded by a SBIR / STTR grant. The government has certain rights in the invention.FIELD OF THE INVENTION

[0003] This application generally relates to systems and methods for continuous direct air capture and electrochemical conversion of CO2 and H2O into ethylene and oxygen in a solid electrolyte reactor.BACKGROUND

[0004] The end-use of carbon-based chemical products results in widespread carbon dioxide (CO2) emissions to the atmosphere, which are challenging to limit in comparison to point sources such as power plants. For this reason, the most effective approach to limiting the carbon footprint of the chemical industry sector is to develop carbon-neutral or carbon-negative methods of producing commodity chemicals.

[0005] Of these efforts, the direct CO2 conversion into chemical products are most promising avenues through biological, thermochemical, photochemical, and electrochemical ways. Specially, electrochemical conversion of CO2 using renewable electricity into chemical products is the real carbon-neutral or carbon negative means to penetrate renewables into chemical products resilient to botany's photosynthesis, but with more controllable and scale-able version. The lab-scale electrochemical reduction of CO2 is majorly into syngas, carbon monoxide, formic acid, methane, methanol, ethylene, ethanol, and n-propanol.SUMMARY OF THE INVENTION

[0006] Devices and methods in accordance with some embodiments of the invention are directed to direct air capture devices and methods for their manufacture and use.

[0007] Various embodiments are directed to a direct air capture device having an electrolyte reactor including a polyethyleneimine PEI800 / zeolite and gyroscopic salt CaCb sorbent material; and a copper or copper oxide covered single-walled carbon nanotube and polyethylene glycol PEO / KOH filled nickel anode.

[0008] In still various embodiments the electrolyte layer is PEO / KOH filled polypropylene.

[0009] In yet various embodiments the cathode is highly conductive nickel coated carbon foam.

[0010] Additional embodiments and features are set forth in part in the description that follows and, in part, will become apparent to those skilled in the art upon examination of the specification or may be learned by the practice of the disclosure. A further understanding of the nature and advantages of the present disclosure may be realized by reference to the remaining portions of the specification and the drawings, which form a part of this disclosure.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The description will be more fully understood with reference to the following figures, which are presented as embodiments of the invention and should not be construed as a complete recitation of the scope of the invention wherein:

[0012] FIG. 1 provides an illustration of the catalytic electrochemical reduction mechanism of direct air captured CO2 and H2O into ethylene and O2, in accordance with some embodiments.

[0013] FIG. 2 provides photographic images of PPE film (the inset is the cross section scanning electron microscope image of PPE film showing 0.2 μm pore size) and PEO / KOH filled PPE film (the inset is PEO / KOH paste) (top), and photographic images of Nickel foam (the inset is the scanning electron microscope image of Nickel foam and PEO / KOH coated Nickel foam (bottom), in accordance with some embodiments.

[0014] FIG. 3 provides a procedure for fabricating highly conductive carbon cathode containing CO2 and H2O direct air capture and electrochemical reduction catalysts carbon nanotubes and copper or copper oxide, wherein: Step 1, is coating HiPCO SWCNTs onto carbon foam, Step 2 is coating copper formate onto carbon foam, Step 3 is decomposing copper formate into copper and copper oxide, Step 4 is adding CO2 sorbent materials PEI 800 / zeolite / sodium alginate, and Step 5 is adding CaCb to crosslink alginate and as H2O sorbent, in accordance with some embodiments.

[0015] FIG. 4 provides images of a direct air capture device in accordance with some embodiments.

[0016] FIG. 5 provides a photographic picture of an F590 Three Gas Analyzer for in-situ measuring of ethylene and O2 in the air (left), and a plot of ethylene concentration in PPM and O2 in percentage against running time respectively obtained from the analyzer, in accordance with some with some embodiments.DETAILED DESCRIPTION OF THE INVENTION

[0017] It will be understood that the components of the embodiments, as generally described herein and illustrated in the appended figures, may be arranged and designed in a variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the present disclosure but is merely representative of various embodiments. While various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0018] The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive.

[0019] Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussions of the features and advantages and similar language throughout this specification may, but do not necessarily, refer to the same embodiment.

[0020] Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description herein, that the invention can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention.

[0021] Reference throughout this specification to “one embodiment,”“an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the indicated embodiment is included in at least one embodiment. Thus, the phrases “in one embodiment,”“in an embodiment,” and similar language throughout this specification may but do not necessarily, all refer to the same embodiment.

[0022] Direct air capture (DAC) and conversion of carbon dioxide into valuable chemicals is an eco-sustainable solution to curb the urgent climate crisis. Embodiments according to the disclosure provide a practical and scalable solid electrolyte electrochemical cell that can directly uptake CO2 and H2O from air and continuously convert them into basic petrochemical ethylene and oxygen with extremely low voltage potential of 0.6 V and 1 A current. This DAC solid electrolyte reactor can produce approximate 70 milli gram ethylene in 1 hour, about 80% energy efficiency and remain in lower temperature.

[0023] Of the major CO2 reduction products, ethylene is the basic feedstock of modern fuel and chemical products. In its Global Ethylene Capacity and Expenditure Outlook in the fourth quarter of 2018, the research firm Research and Markets projected that global production capacity for ethylene will grow from 180 million Mt in 2017 to 270 million Mt in 2026. According to one estimate, ethane cracking generates 1-1.2 Mt CO2 per Mt ethylene produced, while naphtha cracking generates 1.8-2 Mt CO2 per Mt ethylene in current industrial manufacturing.

[0024] With electrochemical reduction of CO2, 3.14 Mt CO2 will be consumed per Mt ethylene produced only using renewable electricity. This will save 4.14-5.14 Mt of CO2 emission in total. In current lab scale electrochemical reduction of CO2 majorly utilizes commercial CO2 to which the capture, storage and transportation could bring about certain carbon emissions. It is very hard to reach carbon neutral or negative electrochemical production.

[0025] Embodiments of the disclosure provide a solid state electrolyte reactor to direct air capture of CO2 and H2O using the CO2 sorbent materials polyethyleneimine PEI 800 / zeolite X 13 and the gyroscopic salt CaCb, and to electrochemically convert them into ethylene and O2 on copper or copper oxide covered single-walled carbon nanotubes and polyethylene glycol (molecular weight 4000) PEO / KOH filled nickel anode, respectively. The solid-state polyelectrolyte reactor continuously functions with 80% energy efficiency and the device temperature remains under 25° C.

[0026] The working principal according to various embodiments is as follows (FIG. 1): PEI / zeolite X 134 absorbs CO2 and hygroscopic calcium chloride absorbs H2O. The adsorbed CO2 will accept one electron from directly contacted SWCNTs and one proton from H2O to form HCOO. The HCOO continuously accepts one electron from SWCNTs and decomposes into CO and HO—. This is demonstrated by the produced CO without copper catalyst. On the nano scale copper surface, CO CO coupling occurs to form ethylene by taking 8 electrons and 8 protons.

[0027] In various embodiments, the electrolyte layer is PEO / KOH filled polypropylene (PP) sheet. Commercial PP with 0.2 μm pore size (as shown in the cross-section SEM image) was filled with PEO / KOH (1 / 0.18 weight ratio) paste (FIG. 2). The solid polyelectrolyte provides the path channels for OH″ migration from conductive cathode to nickel anode under electric field, and the generated water from nickel anode to conductive cathode.

[0028] The anode in various embodiments is PEO / KOH filled nickel foam (II0 PPI, pore size 0.25 mm, MSE Supplies) (FIG. 2). The solid KOH might limit the corrosive that damage Nickel foam. The OH— was oxidized into oxygen and H2O. The oxidized oxygen forms bulbs in PEO / KOH filled nickel foam surface (FIG. 3). The H2O can be attracted back to cathode by gyroscopic salt CaCb.

[0029] In accordance with some embodiments, the consumed OH″ can be supplied by migration of OH″ from cathodes through solid polyelectrolytes. The cathode according to various embodiments is highly conductive carbon foam (1 gram, 100 PPI pore size, 3% relative density, 0.125 inch×4 inch×4 inch, ERG Aerospace) filled with 2 gram HiPCO SWCNTs for facilitating electron reduction reaction coated with copper nanoparticles (2.5 gram) as the catalyst for ethylene formation formed through thermal decomposition of copper formate (FIG. 3). The aqueous solution of copper formate (125 g / L) was soaked onto carbon nanotubes. After water was evaporated, the blue copper formate was coated on carbon nanotubes. The conductive carbon electrode was baked at 90° C. to decompose copper formate into copper and copper oxide (dark brown color). The CO2 sorption materials PEI / zeolites X 13 was filled into the carbon cathode. Sodium alginate was added in as the organic binder when coordinate with hygroscopic calcium chloride which can assist water capture in an arid environment.

[0030] In various embodiments of the direct air capture (DAC) cathode, solid PEO / KOH PP electrolyte layer, and PEO / KOH filled Nickel foam were assembled to form the electrochemical cell (E-cell) (FIG. 4). Copper wires were inserted inside DAC cathode for efficient charge supply. The DAC cathode was contacted to negative DC supplier, and nickel electrode connected to positive DC supplier (GW INSTEK GPS-3303 Laboratory DC power supply) as shown in FIG. 4. To Activate the E-cell, 10-15 V DC is applied. Once the E-cell starts, the potential drops to 0.4-0.6 Volts (much less than the minimum potential difference of 1.23 Volts for H2O hydrolysis) with current up to 1 Ampere. The oxygen bubbles can be clearly observed on PEO / KOH filled Nickel foam (FIG. 4). The E-Cell can continuously run 24 hours seven days and remain the temperature around 25° C. (FIG. 4).

[0031] Without copper nanoparticles, the electroreduction of captured CO2 and H2O produced CO and oxygen. With copper nanoparticles, the electroreduction of captured CO2 and H2O produced ethylene and oxygen. The detected ethylene and oxygen in the open environment using F950 Three Gas Analyzer are shown in FIG. 5. The detected ethylene is up to 200 ppm and the oxygen concentration of oxygen is up to 30% in air.

[0032] In various embodiments, the produced ethylene was trapped with 10 mc liquid (l-Ethyl-3-Methylimidazolium bis(trifluoromethylsufonyl)imide (EMIM TFSI) purchased from Merck (GmbH)). The rest of gas was released to air. The trapped ethylene is about 70 milligram after 1 hour reaction. This is equivalent to 80% electroreduction efficiency.

[0033] In summary, various embodiments of the disclosure describe a novel solid electrolyte reactor comprising of highly conductive cathode capable of direct air capture of CO2 and H2O, PEO / KOH filled PP polyelectrolyte, and PEO / KOH filled Nickel anode continuously function to produce ethylene and O2 with 80% energy efficiency. Direct air capture of CO2 and H2O, according to various embodiments, makes use of CO2 sorbent materials PEI / zeolite X 13 composites and gyroscopic salt CaCb embedded in conductive carbon foams. The incorporated highly conductive single-walled carbon nanotubes act as supports for CO2 and H2O sorbent materials, electron conductors and simultaneously as the effective cathodes for electron injection to PEI bounded CO2 to reduce into CO. The co-existence of PEI with carbon nanotubes can help in stabilizing singly reduced CO2·— and concentrating CO2 on catalyst for electrochemical reduction. The copper and copper oxide on the surface of carbon nanotubes decomposed from copper formate performs as a catalyst for the coupling of in-situ produced CO—CO to yield ethylene and Off by consuming 8 electrons and 8 protons. The formed Off migrated into PEO / KOH filled nickel anode through PEO / KOH filled PPE polyelectrolyte under electric field and oxidized into H2O and O2.INCORPORATED DISCLOSURES

[0034] The following disclosures and references are incorporated herein by reference in their entirety:

[0035] Jouny, M.; Luc, W.; Jiao, F. General Techno-Economic Analysis of CO2 Electrolysis Systems. Industrial & Engineering Chemistry Research, 2018, 57, 2165-2177.

[0036] Q4 2018 Global Ethylene Capacity and Capital Expenditure Outlook—Saude Arabian Oil Co and Exxon Mobil Corp Lead Global Capacity Additions, Research and Markets, https: / / www.researchandmarkets.com / research / q3hg5b / q4_2018_global?w=5 (last visited Apr. 23, 2019

[0037] Tao Ren et al., Olefins from Conventional and Heavy Feedstocks: Energy Use in Steam Cracking and Alternative Processes, 31 Energy 425 (2006), https: / / www.sciencedirect.com / science / article / abs / pii / S0360544205000745

[0038] Xu, X.; Song, C.; Andresen, J.M.; Miller, B. G.; and Scaroni, A. W. Novel Polyethylenimine-Modified Mesoprorous Molecular Sieve of MCM-41 Type as High-Capacity Adsorbent for CO2 Capture. Energy &Fuels 16, no. (2002): 1463-1469.

[0039] Kallenberger, P.A. and Fr6ba, M. Water Harvesting from Air with A Hygroscopic Salt in A Hydrogel Derived Matrix. Communications Chemistry I, No. (2018): 28. DOI:10.1038 / s42004-018-9.

[0040] Zhang, S.; Kang, P.; Ubnoske, S.; M. Brennaman, K.; Song, N.; House, R. L.; Glass, J. T.; Meyer, T. J. Polyethylenimine-Enhanced Electrocatalytic Reduction of CO2 to Formate at Nitrogen-Doped Carbon Nanomaterials. I. Am. Chem. Soc. 2014, 136, 7845-7848.

[0041] Dinh, C.-T.; Burdyny, T.; Kibria, M. G.; Seifitokaldani, A.; Gabardo, C. M. F.; de Arquer, P. G.; Kiani, A.; Edwards, J.P.; De Luna, P.; Bushuyev, 0. S.; Zou, C.; Quintero-Bermudez, R.; Pang, Y.; Sinton, D.; Sargent, E. H. CO2 electroreduction to ethylene via hydroxide-mediated copper catalysis at an abrupt interface. Science 2018, 360, 783-787.

[0042] Li, Y.-R.; Lee, D. U.; Tan, S.; Koshy, D. M.; Lin, T. Y.; Wang, L.; Corral, D.; Aviles Acosta, J.E.; Zamora Zeledon, J. A.; Beck, V. A.; Baker, S. E.; Duoss, E. B.; Hahn, C.; Jaramillo, T. F. Vapor-Fed Electrolyzes for Carbon Dioxide Reduction Using Tandem Electrocatalysts: Cupprous Oxide Coupled with Nickel-Coordinated Nitrogen-Doped Carbon. Advanced Functional Materials, 2022, 32, 2113252 .

[0043] Brown, B. R.; Curreri, P.A.; Rabenberg, E. M.; Dominguez, J. A.; Reidy, L. P.; Dennis, B.; Chanmanee, W. Burke, K. A. Developmental Efforts of an Electrochemical Oxygen Recovery System for Advanced Life Support. 50 th International Conference on Environmental Systems 12-15 July 2021(ICES- 2021-202).

[0044] Prajapati, A.; Kani, N. C.; Gauthier, J. A.; Sartape, R.; Xie, J.; Bessa, I.; Galante, M. T.; Leung, S. L.; Andrade, M. H. S.; Somich, R. T.; Rebouc; as, M. V.; Hutras, G. T.; Diniz, N.; Singh, M. R. CO2-Free High Purity Ethylene from Electroreduction of CO2 with 4% Solar-To-Ethylene and I 0% Solar-to-Carbon Efficiencies. Cell Reports Physical Science, 2022, 3, 101053.

[0045] Shin, D.-H. et al. A Self-Reducible and Alcohol-Soluble Copper-Based Metal-Organic Decomposition Ink for Printed Electronics. ACS Applied Materials & Interface, vol 6, pp. 3312-3319, (2014).DOCTRINE OF EQUIVALENTS

[0046] This description of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications. This description will enable others skilled in the art to best utilize and practice the invention in various embodiments and with various modifications as are suited to a particular use. The scope of the invention is defined by the following claims.

[0047] As used herein, the singular terms “a,”“an,” and “the” may include plural referents unless the context clearly dictates otherwise. Reference to an object in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.”

[0048] As used herein, the terms “approximately” and “about” are used to describe and account for small variations. When used in conjunction with an event or circumstance, the terms can refer to instances in which the event or circumstance occurs precisely as well as instances in which the event or circumstance occurs to a close approximation. When used in conjunction with a numerical value, the terms can refer to a range of variation of less than or equal to ±10% of that numerical value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1 %, less than or equal to ±0.5%, less than or equal to ±0.1 %, or less than or equal to ±0.05%.

[0049] Additionally, amounts, ratios, and other numerical values may sometimes be presented herein in a range format. It is to be understood that such range format is used for convenience and brevity and should be understood flexibly to include numerical values explicitly specified as limits of a range, but also to include all individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly specified. For example, a ratio in the range of about 1 to about 200 should be understood to include the explicitly recited limits of about 1 and about 200, but also to include individual ratios such as about 2, about 3, and about 4, and sub-ranges such as about 10 to about 50, about 20 to about 100, and so forth.

Examples

Embodiment Construction

[0017]It will be understood that the components of the embodiments, as generally described herein and illustrated in the appended figures, may be arranged and designed in a variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the present disclosure but is merely representative of various embodiments. While various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0018]The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive.

[0019]Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invent...

CROSS-REFERENCED APPLICATIONS

[0001] This application is a continuation of U.S. application Ser. No. 18 / 398,125 entitled “Continuous Direct Air Capture and Electrochemical Conversion of CO2 and H2O into Ethylene and Oxygen in Solid Electrolyte Reactor” filed Dec. 27, 2023, the disclosure of which is incorporated by reference in its entirety.GOVERNMENT RIGHTS STATEMENT

[0002] This invention was made with government support under the Grant Number 80NSSC22PB070 awarded by a SBIR / STTR grant. The government has certain rights in the invention.FIELD OF THE INVENTION

[0003] This application generally relates to systems and methods for continuous direct air capture and electrochemical conversion of CO2 and H2O into ethylene and oxygen in a solid electrolyte reactor.BACKGROUND

[0004] The end-use of carbon-based chemical products results in widespread carbon dioxide (CO2) emissions to the atmosphere, which are challenging to limit in comparison to point sources such as power plants. For this reason, the most effective approach to limiting the carbon footprint of the chemical industry sector is to develop carbon-neutral or carbon-negative methods of producing commodity chemicals.

[0005] Of these efforts, the direct CO2 conversion into chemical products are most promising avenues through biological, thermochemical, photochemical, and electrochemical ways. Specially, electrochemical conversion of CO2 using renewable electricity into chemical products is the real carbon-neutral or carbon negative means to penetrate renewables into chemical products resilient to botany's photosynthesis, but with more controllable and scale-able version. The lab-scale electrochemical reduction of CO2 is majorly into syngas, carbon monoxide, formic acid, methane, methanol, ethylene, ethanol, and n-propanol.SUMMARY OF THE INVENTION

[0006] Devices and methods in accordance with some embodiments of the invention are directed to direct air capture devices and methods for their manufacture and use.

[0007] Various embodiments are directed to a direct air capture device having an electrolyte reactor including a polyethyleneimine PEI800 / zeolite and gyroscopic salt CaCb sorbent material; and a copper or copper oxide covered single-walled carbon nanotube and polyethylene glycol PEO / KOH filled nickel anode.

[0008] In still various embodiments the electrolyte layer is PEO / KOH filled polypropylene.

[0009] In yet various embodiments the cathode is highly conductive nickel coated carbon foam.

[0010] Additional embodiments and features are set forth in part in the description that follows and, in part, will become apparent to those skilled in the art upon examination of the specification or may be learned by the practice of the disclosure. A further understanding of the nature and advantages of the present disclosure may be realized by reference to the remaining portions of the specification and the drawings, which form a part of this disclosure.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The description will be more fully understood with reference to the following figures, which are presented as embodiments of the invention and should not be construed as a complete recitation of the scope of the invention wherein:

[0012] FIG. 1 provides an illustration of the catalytic electrochemical reduction mechanism of direct air captured CO2 and H2O into ethylene and O2, in accordance with some embodiments.

[0013] FIG. 2 provides photographic images of PPE film (the inset is the cross section scanning electron microscope image of PPE film showing 0.2 μm pore size) and PEO / KOH filled PPE film (the inset is PEO / KOH paste) (top), and photographic images of Nickel foam (the inset is the scanning electron microscope image of Nickel foam and PEO / KOH coated Nickel foam (bottom), in accordance with some embodiments.

[0014] FIG. 3 provides a procedure for fabricating highly conductive carbon cathode containing CO2 and H2O direct air capture and electrochemical reduction catalysts carbon nanotubes and copper or copper oxide, wherein: Step 1, is coating HiPCO SWCNTs onto carbon foam, Step 2 is coating copper formate onto carbon foam, Step 3 is decomposing copper formate into copper and copper oxide, Step 4 is adding CO2 sorbent materials PEI 800 / zeolite / sodium alginate, and Step 5 is adding CaCb to crosslink alginate and as H2O sorbent, in accordance with some embodiments.

[0015] FIG. 4 provides images of a direct air capture device in accordance with some embodiments.

[0016] FIG. 5 provides a photographic picture of an F590 Three Gas Analyzer for in-situ measuring of ethylene and O2 in the air (left), and a plot of ethylene concentration in PPM and O2 in percentage against running time respectively obtained from the analyzer, in accordance with some with some embodiments.DETAILED DESCRIPTION OF THE INVENTION

[0017] It will be understood that the components of the embodiments, as generally described herein and illustrated in the appended figures, may be arranged and designed in a variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the present disclosure but is merely representative of various embodiments. While various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0018] The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive.

[0019] Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussions of the features and advantages and similar language throughout this specification may, but do not necessarily, refer to the same embodiment.

[0020] Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description herein, that the invention can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention.

[0021] Reference throughout this specification to “one embodiment,”“an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the indicated embodiment is included in at least one embodiment. Thus, the phrases “in one embodiment,”“in an embodiment,” and similar language throughout this specification may but do not necessarily, all refer to the same embodiment.

[0022] Direct air capture (DAC) and conversion of carbon dioxide into valuable chemicals is an eco-sustainable solution to curb the urgent climate crisis. Embodiments according to the disclosure provide a practical and scalable solid electrolyte electrochemical cell that can directly uptake CO2 and H2O from air and continuously convert them into basic petrochemical ethylene and oxygen with extremely low voltage potential of 0.6 V and 1 A current. This DAC solid electrolyte reactor can produce approximate 70 milli gram ethylene in 1 hour, about 80% energy efficiency and remain in lower temperature.

[0023] Of the major CO2 reduction products, ethylene is the basic feedstock of modern fuel and chemical products. In its Global Ethylene Capacity and Expenditure Outlook in the fourth quarter of 2018, the research firm Research and Markets projected that global production capacity for ethylene will grow from 180 million Mt in 2017 to 270 million Mt in 2026. According to one estimate, ethane cracking generates 1-1.2 Mt CO2 per Mt ethylene produced, while naphtha cracking generates 1.8-2 Mt CO2 per Mt ethylene in current industrial manufacturing.

[0024] With electrochemical reduction of CO2, 3.14 Mt CO2 will be consumed per Mt ethylene produced only using renewable electricity. This will save 4.14-5.14 Mt of CO2 emission in total. In current lab scale electrochemical reduction of CO2 majorly utilizes commercial CO2 to which the capture, storage and transportation could bring about certain carbon emissions. It is very hard to reach carbon neutral or negative electrochemical production.

[0025] Embodiments of the disclosure provide a solid state electrolyte reactor to direct air capture of CO2 and H2O using the CO2 sorbent materials polyethyleneimine PEI 800 / zeolite X 13 and the gyroscopic salt CaCb, and to electrochemically convert them into ethylene and O2 on copper or copper oxide covered single-walled carbon nanotubes and polyethylene glycol (molecular weight 4000) PEO / KOH filled nickel anode, respectively. The solid-state polyelectrolyte reactor continuously functions with 80% energy efficiency and the device temperature remains under 25° C.

[0026] The working principal according to various embodiments is as follows (FIG. 1): PEI / zeolite X 134 absorbs CO2 and hygroscopic calcium chloride absorbs H2O. The adsorbed CO2 will accept one electron from directly contacted SWCNTs and one proton from H2O to form HCOO. The HCOO continuously accepts one electron from SWCNTs and decomposes into CO and HO—. This is demonstrated by the produced CO without copper catalyst. On the nano scale copper surface, CO CO coupling occurs to form ethylene by taking 8 electrons and 8 protons.

[0027] In various embodiments, the electrolyte layer is PEO / KOH filled polypropylene (PP) sheet. Commercial PP with 0.2 μm pore size (as shown in the cross-section SEM image) was filled with PEO / KOH (1 / 0.18 weight ratio) paste (FIG. 2). The solid polyelectrolyte provides the path channels for OH″ migration from conductive cathode to nickel anode under electric field, and the generated water from nickel anode to conductive cathode.

[0028] The anode in various embodiments is PEO / KOH filled nickel foam (II0 PPI, pore size 0.25 mm, MSE Supplies) (FIG. 2). The solid KOH might limit the corrosive that damage Nickel foam. The OH— was oxidized into oxygen and H2O. The oxidized oxygen forms bulbs in PEO / KOH filled nickel foam surface (FIG. 3). The H2O can be attracted back to cathode by gyroscopic salt CaCb.

[0029] In accordance with some embodiments, the consumed OH″ can be supplied by migration of OH″ from cathodes through solid polyelectrolytes. The cathode according to various embodiments is highly conductive carbon foam (1 gram, 100 PPI pore size, 3% relative density, 0.125 inch×4 inch×4 inch, ERG Aerospace) filled with 2 gram HiPCO SWCNTs for facilitating electron reduction reaction coated with copper nanoparticles (2.5 gram) as the catalyst for ethylene formation formed through thermal decomposition of copper formate (FIG. 3). The aqueous solution of copper formate (125 g / L) was soaked onto carbon nanotubes. After water was evaporated, the blue copper formate was coated on carbon nanotubes. The conductive carbon electrode was baked at 90° C. to decompose copper formate into copper and copper oxide (dark brown color). The CO2 sorption materials PEI / zeolites X 13 was filled into the carbon cathode. Sodium alginate was added in as the organic binder when coordinate with hygroscopic calcium chloride which can assist water capture in an arid environment.

[0030] In various embodiments of the direct air capture (DAC) cathode, solid PEO / KOH PP electrolyte layer, and PEO / KOH filled Nickel foam were assembled to form the electrochemical cell (E-cell) (FIG. 4). Copper wires were inserted inside DAC cathode for efficient charge supply. The DAC cathode was contacted to negative DC supplier, and nickel electrode connected to positive DC supplier (GW INSTEK GPS-3303 Laboratory DC power supply) as shown in FIG. 4. To Activate the E-cell, 10-15 V DC is applied. Once the E-cell starts, the potential drops to 0.4-0.6 Volts (much less than the minimum potential difference of 1.23 Volts for H2O hydrolysis) with current up to 1 Ampere. The oxygen bubbles can be clearly observed on PEO / KOH filled Nickel foam (FIG. 4). The E-Cell can continuously run 24 hours seven days and remain the temperature around 25° C. (FIG. 4).

[0031] Without copper nanoparticles, the electroreduction of captured CO2 and H2O produced CO and oxygen. With copper nanoparticles, the electroreduction of captured CO2 and H2O produced ethylene and oxygen. The detected ethylene and oxygen in the open environment using F950 Three Gas Analyzer are shown in FIG. 5. The detected ethylene is up to 200 ppm and the oxygen concentration of oxygen is up to 30% in air.

[0032] In various embodiments, the produced ethylene was trapped with 10 mc liquid (l-Ethyl-3-Methylimidazolium bis(trifluoromethylsufonyl)imide (EMIM TFSI) purchased from Merck (GmbH)). The rest of gas was released to air. The trapped ethylene is about 70 milligram after 1 hour reaction. This is equivalent to 80% electroreduction efficiency.

[0033] In summary, various embodiments of the disclosure describe a novel solid electrolyte reactor comprising of highly conductive cathode capable of direct air capture of CO2 and H2O, PEO / KOH filled PP polyelectrolyte, and PEO / KOH filled Nickel anode continuously function to produce ethylene and O2 with 80% energy efficiency. Direct air capture of CO2 and H2O, according to various embodiments, makes use of CO2 sorbent materials PEI / zeolite X 13 composites and gyroscopic salt CaCb embedded in conductive carbon foams. The incorporated highly conductive single-walled carbon nanotubes act as supports for CO2 and H2O sorbent materials, electron conductors and simultaneously as the effective cathodes for electron injection to PEI bounded CO2 to reduce into CO. The co-existence of PEI with carbon nanotubes can help in stabilizing singly reduced CO2·— and concentrating CO2 on catalyst for electrochemical reduction. The copper and copper oxide on the surface of carbon nanotubes decomposed from copper formate performs as a catalyst for the coupling of in-situ produced CO—CO to yield ethylene and Off by consuming 8 electrons and 8 protons. The formed Off migrated into PEO / KOH filled nickel anode through PEO / KOH filled PPE polyelectrolyte under electric field and oxidized into H2O and O2.INCORPORATED DISCLOSURES

[0034] The following disclosures and references are incorporated herein by reference in their entirety:

[0035] Jouny, M.; Luc, W.; Jiao, F. General Techno-Economic Analysis of CO2 Electrolysis Systems. Industrial & Engineering Chemistry Research, 2018, 57, 2165-2177.

[0036] Q4 2018 Global Ethylene Capacity and Capital Expenditure Outlook—Saude Arabian Oil Co and Exxon Mobil Corp Lead Global Capacity Additions, Research and Markets, https: / / www.researchandmarkets.com / research / q3hg5b / q4_2018_global?w=5 (last visited Apr. 23, 2019

[0037] Tao Ren et al., Olefins from Conventional and Heavy Feedstocks: Energy Use in Steam Cracking and Alternative Processes, 31 Energy 425 (2006), https: / / www.sciencedirect.com / science / article / abs / pii / S0360544205000745

[0038] Xu, X.; Song, C.; Andresen, J.M.; Miller, B. G.; and Scaroni, A. W. Novel Polyethylenimine-Modified Mesoprorous Molecular Sieve of MCM-41 Type as High-Capacity Adsorbent for CO2 Capture. Energy &Fuels 16, no. (2002): 1463-1469.

[0039] Kallenberger, P.A. and Fr6ba, M. Water Harvesting from Air with A Hygroscopic Salt in A Hydrogel Derived Matrix. Communications Chemistry I, No. (2018): 28. DOI:10.1038 / s42004-018-9.

[0040] Zhang, S.; Kang, P.; Ubnoske, S.; M. Brennaman, K.; Song, N.; House, R. L.; Glass, J. T.; Meyer, T. J. Polyethylenimine-Enhanced Electrocatalytic Reduction of CO2 to Formate at Nitrogen-Doped Carbon Nanomaterials. I. Am. Chem. Soc. 2014, 136, 7845-7848.

[0041] Dinh, C.-T.; Burdyny, T.; Kibria, M. G.; Seifitokaldani, A.; Gabardo, C. M. F.; de Arquer, P. G.; Kiani, A.; Edwards, J.P.; De Luna, P.; Bushuyev, 0. S.; Zou, C.; Quintero-Bermudez, R.; Pang, Y.; Sinton, D.; Sargent, E. H. CO2 electroreduction to ethylene via hydroxide-mediated copper catalysis at an abrupt interface. Science 2018, 360, 783-787.

[0042] Li, Y.-R.; Lee, D. U.; Tan, S.; Koshy, D. M.; Lin, T. Y.; Wang, L.; Corral, D.; Aviles Acosta, J.E.; Zamora Zeledon, J. A.; Beck, V. A.; Baker, S. E.; Duoss, E. B.; Hahn, C.; Jaramillo, T. F. Vapor-Fed Electrolyzes for Carbon Dioxide Reduction Using Tandem Electrocatalysts: Cupprous Oxide Coupled with Nickel-Coordinated Nitrogen-Doped Carbon. Advanced Functional Materials, 2022, 32, 2113252 .

[0043] Brown, B. R.; Curreri, P.A.; Rabenberg, E. M.; Dominguez, J. A.; Reidy, L. P.; Dennis, B.; Chanmanee, W. Burke, K. A. Developmental Efforts of an Electrochemical Oxygen Recovery System for Advanced Life Support. 50 th International Conference on Environmental Systems 12-15 July 2021(ICES- 2021-202).

[0044] Prajapati, A.; Kani, N. C.; Gauthier, J. A.; Sartape, R.; Xie, J.; Bessa, I.; Galante, M. T.; Leung, S. L.; Andrade, M. H. S.; Somich, R. T.; Rebouc; as, M. V.; Hutras, G. T.; Diniz, N.; Singh, M. R. CO2-Free High Purity Ethylene from Electroreduction of CO2 with 4% Solar-To-Ethylene and I 0% Solar-to-Carbon Efficiencies. Cell Reports Physical Science, 2022, 3, 101053.

[0045] Shin, D.-H. et al. A Self-Reducible and Alcohol-Soluble Copper-Based Metal-Organic Decomposition Ink for Printed Electronics. ACS Applied Materials & Interface, vol 6, pp. 3312-3319, (2014).DOCTRINE OF EQUIVALENTS

[0046] This description of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications. This description will enable others skilled in the art to best utilize and practice the invention in various embodiments and with various modifications as are suited to a particular use. The scope of the invention is defined by the following claims.

[0047] As used herein, the singular terms “a,”“an,” and “the” may include plural referents unless the context clearly dictates otherwise. Reference to an object in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.”

[0048] As used herein, the terms “approximately” and “about” are used to describe and account for small variations. When used in conjunction with an event or circumstance, the terms can refer to instances in which the event or circumstance occurs precisely as well as instances in which the event or circumstance occurs to a close approximation. When used in conjunction with a numerical value, the terms can refer to a range of variation of less than or equal to ±10% of that numerical value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1 %, less than or equal to ±0.5%, less than or equal to ±0.1 %, or less than or equal to ±0.05%.

[0049] Additionally, amounts, ratios, and other numerical values may sometimes be presented herein in a range format. It is to be understood that such range format is used for convenience and brevity and should be understood flexibly to include numerical values explicitly specified as limits of a range, but also to include all individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly specified. For example, a ratio in the range of about 1 to about 200 should be understood to include the explicitly recited limits of about 1 and about 200, but also to include individual ratios such as about 2, about 3, and about 4, and sub-ranges such as about 10 to about 50, about 20 to about 100, and so forth.

Examples

Embodiment Construction

[0017]It will be understood that the components of the embodiments, as generally described herein and illustrated in the appended figures, may be arranged and designed in a variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the present disclosure but is merely representative of various embodiments. While various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0018]The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive.

[0019]Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invent...

Claims

1. A direct air capture device comprising:a cathode, wherein the cathode layer comprises a CO2 sorbent material, an H2O sorbent material, a CO2 electrochemical reduction promoter and a CO2 electrochemical catalyst;an anode, wherein an oxygen evolving reaction occurs; anda solid electrolyte film disposed between the cathode and the anode.

2. The device of claim 1, wherein the solid electrolyte film is a solid.

3. The device of claim 2, wherein the solid electrolyte film is a porous sheet.

4. The device of claim 3, wherein the solid electrolyte film porous sheets are selected from the group consisting of: inorganic glasses, ceramics, polymers, and ionic polymers.

5. The device of claim 4, wherein the polymers are selected from the group consisting of polyethylene, polypropylene, polyimide, polysulfonate, polycarbonate, polyether, fluorinated polymers, polystyrene, and polyvinyl.

6. The device of claim 4, wherein the ionic polymer is selected from the group consisting of Nafion and polystyenesulfate.

7. The device of claim 3, wherein the solid electrolyte film is a porous polypropylene filled with KOH / polyethylene oxide such that OH— migrates from the cathode to the anode and H2O migrates from the anode to the cathode.

8. The device of claim 1, wherein the CO2 sorbent material is selected from the group consisting of molecular sieves, zeolites, organic amines, polyamines, metal organic framework materials, and combinations thereof.

9. The device of claim 8, wherein the CO2 sorbent material is a combination of polyethyleneimine and zeolite 13X.

10. The device of claim 1, wherein the H2O sorbent material is selected from the group consisting of molecular sieves, zeolites, organic amines, polyamines, polyethylene oxides, metal organic framework materials, ionic polymers, CaCl2, and combinations thereof.

11. The device of claim 10, wherein the H2O sorbent material is a combination of CaCl2 and alginate.

12. The device of claim 1, wherein the CO2 electroreduction promoter is selected from the group consisting of multiwalled carbon nanotubes, double-walled carbon nanotubes, single-walled carbon nanotubes, graphenes, conductive carbon nanofibers, and conductive nanowires.

13. The device of claim 12, wherein the CO2 electroreduction promoter is formed of high pressure CO conversion single-walled carbon nanotubes such that electron injection is facilitated to reduce CO2 into CO.

14. The device of claim 1, wherein the CO2 electroreduction promoter is selected from the group consisting of organic amines, polyamines, and metal organic frameworks.

15. The device of claim 14, wherein the CO2 electroreduction promoter is polyethyleneimine.

16. The device of claim 1, wherein the CO2 electroreduction catalyst is selected from the group consisting of nanosize or microsize metals, and metal oxides.

17. The device of claim 16, wherein the CO2 electroreduction catalyst is at least one of nano copper and nano copper oxide.

18. The device of claim 17, wherein the nano copper and nano copper oxide are disposed on a side surface of a plurality of carbon nanotubes.

19. The device of claim 18, wherein the nano copper and nano copper oxide are made using a technique selected from the group consisting of physical vapor deposition, chemical vapor deposition, and chemical reduction decomposition.

20. The device of claim 18, wherein the nano copper and nano copper oxide disposed on the surface of a plurality of carbon nanotubes are formed from the reduction decomposition of copper formate.

21. The device of claim 1, wherein the anode is selected from the group consisting of nickel, nickel iron, iron, iridium and other oxygen evolving reaction electrodes.

22. The device of claim 21, wherein the anode is nickel foam.

23. The device of claim 22, wherein the nickel foam is filled with solid state KOH / polyethylene oxide electrolyte composites such that high concentrated hydroxide anions are provided for oxidation such that O2 and H2O are generated.

24. The device of claim 1, wherein the direct air capture device operates in less than 0.4 V at 1 Amp power supply with an energy efficiency of 80%.

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