METHODS OF USING A MIXED CONDUCTING MEMBRANE UNDER HIGH PRESSURES

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. 119(e) of U.S. Provisional Patent Application No. 63/717,734 filed Nov. 7, 2024, the entire disclosure of which is hereby incorporated herein by reference.

TECHNICAL FIELD

This invention generally relates to mixed conducting membranes. More specifically, this invention relates to methods of using mixed conducting membranes under high pressures.

BACKGROUND

Carbon monoxide (CO) is a colorless, odorless, tasteless, and flammable gas that is slightly less dense than air. It is well known for its poisoning effect because CO readily combines with hemoglobin to produce carboxyhemoglobin, which is highly toxic when the concentration exceeds a certain level. However, CO is a key ingredient in many chemical and industrial processes. CO has a wide range of functions across all disciplines of chemistry, e.g., metal-carbonyl catalysis, radical chemistry, cation and anion chemistries. Carbon monoxide is a strong reductive agent and has been used in pyrometallurgy to reduce metals from ores for centuries. As an example for making specialty compounds, CO is used in the production of vitamin A.

Hydrogen (H₂) in large quantities is needed in the petroleum and chemical industries. For example, large amounts of hydrogen are used in upgrading fossil fuels and in the production of methanol or hydrochloric acid. Petrochemical plants need hydrogen for hydrocracking, hydrodesulfurization, hydrodealkylation. Hydrogenation processes to increase the level of saturation of unsaturated fats and oils also need hydrogen. Hydrogen is also a reducing agent of metallic ores. Hydrogen may be produced from electrolysis of water, steam reforming, lab-scale metal-acid process, thermochemical methods, or anaerobic corrosion. Many countries are aiming for a hydrogen economy.

In the Fischer-Tropsch process, CO and H₂ are both essential building blocks, which are often produced by converting carbon-rich feedstocks (e.g., coal). A mixture of CO and H₂—syngas—can combine to produce various liquid fuels, e.g., via the Fischer-Tropsch process. Syngas can also be converted to lighter hydrocarbons, methanol, ethanol, or plastic monomers (e.g., ethylene). The ratio of CO/H₂ is important in all such processes in order to produce the desired compounds. Conventional techniques require extensive and expensive separation and purification processes to obtain the CO and H₂ as building blocks.

Clearly there is an increasing need and interest to develop new technological platforms to produce these building blocks and valuable products. This disclosure discusses the production of CO and/or H₂ via efficient electrochemical pathways using mixed conducting membranes. Furthermore, the method and system as disclosed herein operate at higher pressures that are contrary to conventional wisdom.

SUMMARY

Herein discussed is a method comprising: providing a mixed conducting membrane; exposing the membrane to a reducing environment on both sides of the membrane during the entire time of operation, wherein the operation does not receive electricity or generate electricity; wherein the reducing environments on both sides of the membrane have a pressure in the range of 5-300 bar.

In an embodiment, the mixed conducting membrane conducts electrons and oxide ions. In an embodiment, the reducing environments on both sides of the membrane have a pressure of no less than 10 bar or no less than 20 bar or no less than 30 bar.

In an embodiment, the membrane comprises lanthanum chromite and a material selected from the group consisting of doped ceria, yttria-stabilized zirconia (YSZ), lanthanum strontium gallate magnesite (LSGM), scandia-stabilized zirconia (SSZ), Sc and Ce doped zirconia, and combinations thereof. In an embodiment, the lanthanum chromite comprises undoped lanthanum chromite, strontium doped lanthanum chromite, iron doped lanthanum chromite, strontium and iron doped lanthanum chromite, lanthanum calcium chromite, or combinations thereof.

In an embodiment, the membrane comprises an electronically conducting phase and an ionically conducting phase. In an embodiment, the electronically conducting phase comprises doped lanthanum chromite or an electronically conductive metal or combination thereof; and wherein the ionically conducting phase comprises a material selected from the group consisting of gadolinium or samarium doped ceria, yttria-stabilized zirconia (YSZ), lanthanum strontium gallate magnesite (LSGM), scandia-stabilized zirconia (SSZ), Sc and Ce doped zirconia (SCZ), and combinations thereof.

In an embodiment, the membrane comprises CoCGO or LST (lanthanum-doped strontium titanate)-stabilized zirconia. In an embodiment, the stabilized zirconia comprises YSZ or SSZ or SCZ (scandia-ceria-stabilized zirconia), and wherein the LST comprises LaSrCaTiO₃. In an embodiment, the membrane comprises Nickel, Copper, Cobalt, or Niobium-doped zirconia.

In an embodiment, one side of the membrane is in contact with a cathode at which steam is electrochemically reduced to produce hydrogen or carbon dioxide is electrochemically reduced to produce carbon monoxide. In an embodiment, the cathode comprises Ni or NiO and a material selected from the group consisting of YSZ, CGO, SDC, SSZ, SCZ, LSGM, CoCGO, LST, and combinations thereof. In an embodiment, the cathode comprises Ni—YSZ or Ni-CGO or LaSrFcCr-SSZ or LaSrFeCr—SCZ or LST (lanthanum-doped strontium titanate)-SCZ.

In an embodiment, the opposite side of the membrane is in contact with an anode that receives a fuel, wherein the fuel does not mix with cathode feed directly. In an embodiment, the fuel comprises a hydrocarbon or hydrogen or carbon monoxide or ammonia or combinations thereof.

In an embodiment, the anode comprises Ni or NiO and a material selected from the group consisting of YSZ, CGO, SDC, SSZ, LSGM, and combinations thereof. In an embodiment, the anode comprises doped or undoped ceria and a material selected from the group consisting of Cu, CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃, Pt, Pd, Ru, Rh, Ir, LaCaCr, LaSrCrFe, YSZ, CGO, SDC, SSZ, LSGM, stainless steel, and combinations thereof.

In an embodiment, the anode comprises lanthanum chromite and a material selected from the group consisting of doped ceria, yttria-stabilized zirconia (YSZ), lanthanum strontium gallate magnesite (LSGM), scandia-stabilized zirconia (SSZ), Sc and Ce doped zirconia, and combinations thereof; wherein optionally the lanthanum chromite comprises undoped lanthanum chromite, strontium doped lanthanum chromite, iron doped lanthanum chromite, strontium and iron doped lanthanum chromite, lanthanum calcium chromite, or combinations thereof.

In an embodiment, the membrane is tubular. In an embodiment, the reducing environments on both sides of the membrane have a temperature of no less than 600° C., or no less than 700° C., or no less than 800° C., or no less than 900° C.

Further aspects and embodiments are provided in the foregoing drawings, detailed description and claims. Unless specified otherwise, the features as discussed herein are combinable and all such combinations are within the scope of this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings are provided to illustrate certain embodiments described herein. The drawings are merely illustrative and are not intended to limit the scope of claimed inventions and are not intended to show every potential feature or embodiment of the claimed inventions. The drawings are not necessarily drawn to scale; in some instances, certain elements of the drawing may be enlarged with respect to other elements of the drawing for purposes of illustration.

FIG. 1 illustrates an electrochemical (EC) gas producer comprising a mixed conducting membrane, according to an embodiment of this disclosure.

FIG. 2A illustrates a tubular EC gas producer containing a mixed conducting membrane, according to an embodiment of this disclosure.

FIG. 2B illustrates a cross section of a tubular EC gas producer comprising a mixed conducting membrane, according to an embodiment of this disclosure.

DETAILED DESCRIPTION

The following description recites various aspects and embodiments of the inventions disclosed herein. No particular embodiment is intended to define the scope of the invention. Rather, the embodiments provide non-limiting examples of various compositions, and methods that are included within the scope of the claimed inventions. The description is to be read from the perspective of one of ordinary skill in the art. Therefore, information that is well known to the ordinarily skilled artisan is not necessarily included.

Overview

Herein discussed is a method of using a mixed conducting membrane comprising exposing the membrane to a reducing environment on both sides of the membrane during the entire time of operation. In an embodiment, the membrane conducts electrons and oxide ions. In various embodiments, the membrane is impermeable to fluid flow (e.g., having a permeability of less than 1 micro darcy). In various embodiments, the operation of the membrane does not receive electricity or generate electricity. Furthermore, the reducing environments on both sides of the membrane have a pressure in a range of 5-300 bar. The method and system of this disclosure are contrary to traditional practices in the art. SOFCs (solid oxide fuel cells) produce electricity and SOECs (solid oxide electrolysis cells) receive electricity. The membranes in SOFCs and SOECs must NOT be electronically conductive. Otherwise, the SOFCs and SOECs would both be short circuited internally and fail to perform their intended functions. Clearly, the device/system of this disclosure is not a SOFC or SOEC. Furthermore, SOFCs (solid oxide fuel cells) and SOECs (solid oxide electrolysis cells) are typically operated at a pressure of 1-3 bar, well below 5 bar.

It has been unexpectedly discovered that when the device of this disclosure is operated at higher pressures (e.g., from 5 bar to 300 bar), the electrochemical performance of the device is improved. In various embodiments, the operating pressure is no less than 10 bar or no less than 20 bar or no less than 30 bar. This is contrary to conventional wisdom because higher gas pressures are known to reduce electronic conductivity in the mixed-conducting membrane. Nevertheless, the electrochemical performance of the device is not reduced but rather improved, especially when the reducing environments on both sides of the membrane have a temperature of no less than 600° C., or no less than 700° C., or no less than 800° C., or no less than 900° C. In addition, it has been unexpectedly discovered that when the device of this disclosure is operated at higher pressures (e.g., from 5 bar to 300 bar), the stability of the membrane is preserved and strengthened. Traditionally, oxide-ion conducting membranes are prone to degradation and structural failure because of the high operating temperatures and the presence of oxide ions. Without wishing to be limited by any theory, operation under higher pressures reduces and minimizes membrane degradation and structural failure.

The following terms and phrases have the meanings indicated below, unless otherwise provided herein. This disclosure may employ other terms and phrases not expressly defined herein. Such other terms and phrases shall have the meanings that they would possess within the context of this disclosure to those of ordinary skill in the art. In some instances, a term or phrase may be defined in the singular or plural. In such instances, it is understood that any term in the singular may include its plural counterpart and vice versa, unless expressly indicated to the contrary.

As used herein, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. For example, reference to “a substituent” encompasses a single substituent as well as two or more substituents, and the like. As used herein, “for example,” “for instance,” “such as,” or “including” are meant to introduce examples that further clarify more general subject matter. Unless otherwise expressly indicated, such examples are provided only as an aid for understanding embodiments illustrated in the present disclosure and are not meant to be limiting in any fashion. Nor do these phrases indicate any kind of preference for the disclosed embodiment.

As used herein, compositions and materials are used interchangeably unless otherwise specified. Each composition/material may have multiple elements, phases, and components. Heating as used herein refers to actively adding energy to the compositions or materials.

As used herein, YSZ refers to yttria-stabilized zirconia; SDC refers to samaria-doped ceria; SSZ refers to scandia-stabilized zirconia; LSGM refers to lanthanum strontium gallate magnesite.

In this disclosure, no substantial amount of H₂ means that the volume content of the hydrogen is no greater than 5%, or no greater than 3%, or no greater than 2%, or no greater than 1%, or no greater than 0.5%, or no greater than 0.1%, or no greater than 0.05%.

As used herein, CGO refers to Gadolinium-Doped Ceria, also known alternatively as gadolinia-doped ceria, gadolinium-doped cerium oxide, cerium (IV) oxide, gadolinium-doped, GDC, or GCO, (formula Gd:CeO₂). CGO and GDC are used interchangeably unless otherwise specified. Syngas (i.e., synthesis gas) in this disclosure refers to a mixture consisting primarily of hydrogen, carbon monoxide and carbon dioxide.

A mixed conducting membrane is able to transport both electrons and ions. Ionic conductivity includes ionic species such as oxygen ions (or oxide ions), protons, halogenide anions, chalcogenide anions. In various embodiments, the mixed conducting membrane of this disclosure comprises an electronically conducting phase and an ionically conducting phase.

In this disclosure, the axial cross section of the tubulars is shown to be circular, which is illustrative only and not limiting. The axial cross section of the tubulars is any suitable shape as known to one skilled in the art, such as square, square with rounded corners, rectangle, rectangle with rounded corners, triangle, hexagon, pentagon, oval, irregular shape, etc.

As used herein, ceria refers to cerium oxide, also known as ceric oxide, ceric dioxide, or cerium dioxide, is an oxide of the rare-earth metal cerium. Doped ceria refers to ceria doped with other elements, such as samaria-doped ceria (SDC), or gadolinium-doped ceria (GDC or CGO). As used herein, chromite refers to chromium oxides, which includes all the oxidation states of chromium oxides.

A layer or substance being impermeable as used herein refers to it being impermeable to fluid flow. For example, an impermeable layer or substance has a permeability of less than 1 micro darcy, or less than 1 nano darcy.

In this disclosure, sintering refers to a process to form a solid mass of material by heat or pressure, or a combination thereof, without melting the material to the extent of liquefaction. For example, material particles are coalesced into a solid or porous mass by being heated, wherein atoms in the material particles diffuse across the boundaries of the particles, causing the particles to fuse together and form one solid piece.

The term “in situ” in this disclosure refers to the treatment (e.g., heating or cracking) process being performed either at the same location or in the same device. For example, ammonia cracking taking place in the electrochemical reactor at the anode is considered in situ.

Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential, as a measurable and quantitative phenomenon, and identifiable chemical change, with either electrical potential as an outcome of a particular chemical change, or vice versa. These reactions, for example, involve electrons moving between electrodes via an electronically-conducting phase (typically, but not necessarily, an external electrical circuit), separated by an ionically-conducting and electronically insulating membrane (or ionic species in a solution). When a chemical reaction is effected by a potential difference, as in electrolysis, or if electrical potential results from a chemical reaction as in a battery or fuel cell, it is called an electrochemical reaction. Unlike chemical reactions, in electrochemical reactions electrons (and necessarily resulting ions), are not transferred directly between molecules, but via the aforementioned electronically conducting and ionically conducting circuits, respectively. This phenomenon is what distinguishes an electrochemical reaction from a chemical reaction.

Related to the electrochemical reactor and methods of use, various components of the reactor are described such as electrodes and membranes along with materials of construction of the components. The following description recites various aspects and embodiments of the inventions disclosed herein. No particular embodiment is intended to define the scope of the invention. Rather, the embodiments provide non-limiting examples of various compositions and methods that are included within the scope of the claimed inventions. The description is to be read from the perspective of one of ordinary skill in the art. Therefore, information that is well-known to the ordinarily skilled artisan is not necessarily included.

An interconnect in an electrochemical device (e.g., a fuel cell) is often either metallic or ceramic that is placed between the individual cells or repeat units. Its purpose is to connect each cell or repeat unit so that electricity can be distributed or combined. An interconnect is also referred to as a bipolar plate in an electrochemical device. An interconnect being an impermeable layer as used herein refers to it being a layer that is impermeable to fluid flow.

EC Gas Producer

FIG. 1 illustrates an electrochemical (EC) gas producer device 100, according to an embodiment of this disclosure. The EC gas producer device 100 comprises a first electrode (or anode) 101, a mixed conducting membrane (or electrolyte) 103, and a second electrode (or cathode) 102. First electrode 101 is configured to receive a fuel and no oxygen, as represented by arrow 104. Second electrode 102 is configured to receive water or carbon dioxide as denoted by arrow 105. In various embodiments, the fuel comprises a hydrocarbon or hydrogen or carbon monoxide or ammonia or combinations thereof.

In an embodiment, device 100 is configured to receive CO, i.e., carbon monoxide (104) and to generate CO/CO₂ (106) at the first electrode (101); device 100 is also configured to receive water or steam (105) and to generate hydrogen (107) at the second electrode (102). In some cases, the second electrode receives a mixture of steam and hydrogen. In various embodiments, 103 represents a mixed conducting membrane and both sides of the membrane are exposed to a reducing environment. In an embodiment, the first electrode 101 and the second electrode 102 may comprise Ni—YSZ or NiO—YSZ. 103 is also referred to as a membrane or an electrolyte unless otherwise specified. The gas producer as discussed herein is an example of using a mixed conducting membrane (i.e. 103) comprising exposing the mixed conducting membrane to a reducing environment on both sides.

In an embodiment, device 100 is configured to simultaneously produce hydrogen 107 from the second electrode 102 and syngas 106 from the first electrode 101. In an embodiment, arrow 104 represents methane and water or methane and carbon dioxide entering the device 100. In other embodiments, 103 represents a mixed conducting membrane. In an embodiment, first electrode 101 and second electrode 102 may comprise Ni—YSZ or NiO—YSZ. Arrow 104 represents an influx of hydrocarbon and water or hydrocarbon and carbon dioxide. Arrow 105 represents an influx of water or water and hydrogen. In some embodiments, electrode 101 comprises Cu-CGO, or further optionally comprises CuO or Cu₂O or combination thereof. Electrode 102 comprises Ni—YSZ or NiO—YSZ. Arrow 104 represents an influx of hydrocarbons with little to no water, with no carbon dioxide, and with no oxygen, and arrow 105 represents an influx of water or water and hydrogen.

In this disclosure, no oxygen means there is no oxygen present at first electrode 101 or at least not enough oxygen that would interfere with the reaction. Also, in this disclosure, water only means that the intended feedstock is water and does not exclude trace elements or inherent components in water. For example, water containing salts or ions is within the scope of water only. Water only also does not require 100% pure water but includes this embodiment. In embodiments, the hydrogen produced from second electrode 102 is pure hydrogen, which means that in the produced gas phase from the second electrode, hydrogen is the main component. In some cases, the hydrogen content is no less than 99.5%. In some cases, the hydrogen content is no less than 99.9%. In some cases, the hydrogen produced from the second electrode is the same purity as that produced from electrolysis of water.

In an embodiment, first electrode 101 is configured to receive methane and water or methane and carbon dioxide. In an embodiment, the fuel comprises a hydrocarbon having a carbon number in the range of 1-12, 1-10 or 1-8. Most preferably, the fuel is methane or natural gas, which is predominantly methane. In an embodiment, the device does not generate electricity. In an embodiment, the device comprises a mixer configured to receive at least a portion of the first electrode product and at least a portion of the second electrode product. The mixer may be configured to generate a gas stream in which the hydrogen to carbon oxides ratio is no less than 2, or no less than 3 or between 2 and 3. Such mixed gas streams, for example, are suitable as feed for Fischer Tropsch reactions/reactors.

In some embodiments, the electrodes and mixed conducting membrane form a repeat unit. A device may comprise two or more repeat units. In an embodiment, the device comprises no interconnect. In an embodiment, the electrodes 101, 102 and the mixed conducting membrane 103 are tubular (see, e.g., FIGS. 2A and 2B). In an embodiment, the electrodes 101, 102 and the mixed conducting membrane 103 are planar. In various embodiments, the electrochemical reactions at the anode and the cathode are spontaneous without the need to apply potential/electricity to the reactor.

In an embodiment, the gas producer (or EC gas producer) is a device comprising a first electrode, a second electrode, and a mixed conducting membrane between the electrodes, wherein the first electrode and the second electrode comprise a metallic phase that does not contain a platinum group metal when the device is in use. In an embodiment, wherein the first electrode comprises Ni or NiO and a material selected from the group consisting of YSZ, CGO, samaria-doped ceria (SDC), scandia-stabilized zirconia (SSZ), LSGM, and combinations thereof. In an embodiment, the first electrode is configured to receive a fuel and water or a fuel and carbon dioxide.

In an embodiment, said fuel comprises a hydrocarbon or hydrogen or carbon monoxide or combinations thereof. In an embodiment, the first electrode comprises doped or undoped ceria and a material selected from the group consisting of Cu, CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃, stainless steel, and combinations thereof. In an embodiment, the first electrode is configured to receive a fuel with little to no water. In an embodiment, said fuel comprises a hydrocarbon or hydrogen or carbon monoxide or combinations thereof. In an embodiment, the second electrode comprises Ni or NiO and a material selected from the group consisting of yttria-stabilized zirconia (YSZ), ceria gadolinium oxide (CGO), samaria-doped ceria (SDC), scandia-stabilized zirconia (SSZ), lanthanum strontium gallate magnesite (LSGM), and combinations thereof. In an embodiment, the second electrode is configured to receive water and hydrogen and configured to reduce the water to hydrogen.

FIG. 2A illustrates (not to scale) a tubular gas producer or an EC gas producer 200, according to an embodiment of this disclosure. Tubular producer 200 includes an inner tubular structure 202, an outer tubular structure 204, and a mixed conducting membrane 206 disposed between the inner and outer tubular structures 202, 204, respectively. Tubular producer 200 further includes a void space 208 for fluid passage. FIG. 2B illustrates (not to scale) a cross section of a tubular producer 200, according to an embodiment of this disclosure. Tubular producer 200 includes a first inner tubular structure 202, a second outer tubular structure 204, and a mixed conducting membrane 206 between the inner and outer tubular structures 202, 204. In some embodiments, mixed conducting membrane 206 may be referred to as a membrane. Tubular producer 200 further includes a void space 208 for fluid passage.

In an embodiment, the electrodes and the mixed conducting membrane are tubular with the first electrode being outermost and the second electrode being innermost, wherein the first electrode (or anode) comprises doped or undoped ceria and a material selected from the group consisting of Cu, CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃, stainless steel, and combinations thereof. In an embodiment, the electrodes and the mixed conducting membrane are tubular with the first electrode being outermost and the second electrode being innermost, wherein the second electrode (or cathode) is configured to receive water and hydrogen. In an embodiment, the electrodes and the mixed conducting membrane are tubular with the first electrode being innermost and the second electrode being outermost, wherein the second electrode is configured to receive water and hydrogen. In an embodiment, the electrodes and the mixed conducting membrane are tubular, wherein the first and second electrodes comprise Ni—YSZ or NiO—YSZ.

Method of Using

Herein discussed is a method comprising: providing a mixed conducting membrane; exposing the membrane to a reducing environment on both sides of the membrane during the entire time of operation, wherein the operation does not receive electricity or generate electricity; wherein the reducing environments on both sides of the membrane have a pressure in the range of 5-300 bar.

In an embodiment, the mixed conducting membrane conducts electrons and oxide ions. In an embodiment, the reducing environments on both sides of the membrane have a pressure of no less than 10 bar or no less than 20 bar or no less than 30 bar.

In an embodiment, the membrane comprises lanthanum chromite and a material selected from the group consisting of doped ceria, yttria-stabilized zirconia (YSZ), lanthanum strontium gallate magnesite (LSGM), scandia-stabilized zirconia (SSZ), Sc and Ce doped zirconia, and combinations thereof. In an embodiment, the lanthanum chromite comprises undoped lanthanum chromite, strontium doped lanthanum chromite, iron doped lanthanum chromite, strontium and iron doped lanthanum chromite, lanthanum calcium chromite, or combinations thereof.

In an embodiment, the membrane comprises an electronically conducting phase and an ionically conducting phase. In an embodiment, the electronically conducting phase comprises doped lanthanum chromite or an electronically conductive metal or combination thereof; and wherein the ionically conducting phase comprises a material selected from the group consisting of gadolinium or samarium doped ceria, yttria-stabilized zirconia (YSZ), lanthanum strontium gallate magnesite (LSGM), scandia-stabilized zirconia (SSZ), Sc and Ce doped zirconia (SCZ), and combinations thereof.

In an embodiment, the membrane comprises CoCGO or LST (lanthanum-doped strontium titanate)-stabilized zirconia. In an embodiment, the stabilized zirconia comprises YSZ or SSZ or SCZ (scandia-ceria-stabilized zirconia), and wherein the LST comprises LaSrCaTiO₃. In an embodiment, the membrane comprises Nickel, Copper, Cobalt, or Niobium-doped zirconia.

In an embodiment, one side of the membrane is in contact with a cathode at which steam is electrochemically reduced to produce hydrogen or carbon dioxide is electrochemically reduced to produce carbon monoxide. In an embodiment, the cathode comprises Ni or NiO and a material selected from the group consisting of YSZ, CGO, SDC, SSZ, SCZ, LSGM, CoCGO, LST, and combinations thereof. In an embodiment, the cathode comprises Ni—YSZ or Ni-CGO or LaSrFeCr—SSZ or LaSrFeCr—SCZ or LST (lanthanum-doped strontium titanate)-SCZ.

In an embodiment, the opposite side of the membrane is in contact with an anode that receives a fuel, wherein the fuel does not mix with cathode feed directly. In an embodiment, the fuel comprises a hydrocarbon or hydrogen or carbon monoxide or ammonia or combinations thereof.

In an embodiment, the anode comprises Ni or NiO and a material selected from the group consisting of YSZ, CGO, SDC, SSZ, LSGM, and combinations thereof. In an embodiment, the anode comprises doped or undoped ceria and a material selected from the group consisting of Cu, CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃, Pt, Pd, Ru, Rh, Ir, LaCaCr, LaSrCrFe, YSZ, CGO, SDC, SSZ, LSGM, stainless steel, and combinations thereof.

In an embodiment, the anode comprises lanthanum chromite and a material selected from the group consisting of doped ceria, yttria-stabilized zirconia (YSZ), lanthanum strontium gallate magnesite (LSGM), scandia-stabilized zirconia (SSZ), Sc and Ce doped zirconia, and combinations thereof; wherein optionally the lanthanum chromite comprises undoped lanthanum chromite, strontium doped lanthanum chromite, iron doped lanthanum chromite, strontium and iron doped lanthanum chromite, lanthanum calcium chromite, or combinations thereof.

In an embodiment, the membrane is tubular. In an embodiment, the reducing environments on both sides of the membrane have a temperature of no less than 600° C., or no less than 700° C., or no less than 800° C., or no less than 900° C.

Production of Valuable Products

In an embodiment, the method comprises using the extracted hydrogen in one of Fischer-Tropsch (FT) reactions, dry reforming reactions, Sabatier reaction catalyzed by nickel, Bosch reaction, reverse water gas shift reaction, electrochemical reaction to produce electricity, production of ammonia, production of fertilizer, electrochemical compressor for hydrogen storage, fueling hydrogen vehicles or hydrogenation reactions or combinations thereof.

In various embodiments, an additional apparatus or system is integrated with one or more EC producers outputting H₂ and CO. The additional apparatus or system is selected from the group consisting of Fischer-Tropsch reactor, methanol producer, ethanol producer, hydrocarbon producer, plastic monomer producer, and combinations thereof. The Fischer-Tropsch reactor is able to generate valuable products such as naphtha, gasoline, diesel, wax. The produced methanol may be further converted to gasoline, ethylene, acetic acid, formaldehyde, methyl acetate, polyolefins, dimethyl ether (DME), or combinations thereof. Additionally, the system may comprise a polymerization unit to convert the plastic monomers to various types of plastics. The configurations and arrangements for utilizing the produced CO and H₂ are known to one skilled in the art, and all such configurations and arrangements are within the scope of this disclosure.

It is to be understood that this disclosure describes exemplary embodiments for implementing different features, structures, or functions of the invention. Exemplary embodiments of components, arrangements, and configurations are described to simplify the present disclosure; however, these exemplary embodiments are provided merely as examples and are not intended to limit the scope of the invention. The embodiments as presented herein may be combined unless otherwise specified. Such combinations do not depart from the scope of the disclosure.

Additionally, certain terms are used throughout the description and claims to refer to particular components or steps. As one skilled in the art appreciates, various entities may refer to the same component or process step by different names, and as such, the naming convention for the elements described herein is not intended to limit the scope of the invention. Further, the terms and naming convention used herein are not intended to distinguish between components, features, and/or steps that differ in name but not in function.

While the disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and description. It should be understood, however, that the drawings and detailed description are not intended to limit the disclosure to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of this disclosure.