Permeation distillation electrolysis device and method

Abstract

An osmotic distillation electrolyzer includes an anode and a cathode in first and second chambers in fluid communication with each other only through a diaphragm. The retort electrolyzer includes a membrane and a non-porous baffle slidably engaged relative to the membrane. The transport path is achieved at least in part by an osmotic pressure difference between the stock solution and the first electrolyte solution and / or at least in part by a vapor pressure difference across the membrane. The membrane may form a portion of a wall of one or both of the first and second chambers, wherein the membrane intervenes in each of one or more transport paths from the water source toward the pool. Alternatively, the membrane may be disposed outside of the cell, and the distillation electrolysis device may include an electrolyte storage tank externally connected to the cell.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority to Singapore application number 10202250857K filed on August 30, 2022, the contents of which are incorporated herein by reference in their entirety for all purposes. Technical Field

[0003] The present application relates to hydrogen production or water splitting. Background Art

[0004] Conventional water electrolyzers require highly purified deionized water for water decomposition and the generation of hydrogen. Impurities in unpurified water, such as dissolved salts, organic molecules, microorganisms, and particulate matter, can corrode electrocatalysts, produce parasitic electrochemical reactions, and inhibit the water decomposition process. For example, chloride anions can pose a severe challenge to the anode (an electrode set to an oxidizing and positive potential). The chlorine evolution reaction can compete with the oxygen evolution reaction on the anode, while the generated chlorine gas can corrode components in the electrochemical cell (such as electrodes, catalysts, and diaphragms) and even damage the electrolyzer. For the cathode (the electrode set to a reducing and negative potential), such as Ca 2+ and Mg 2+ The presence of divalent ions can form precipitation of carbonaceous species (e.g., CaCO3, MgCO3) and hydroxylated species (e.g., Ca(OH)2, Mg(OH)2) on the cathode surface. These precipitates can block the active areas of the electrode and catalyst, inhibiting the hydrogen evolution reaction at the cathode. Cleaning usually involves the use of acid solutions to dissolve the precipitates. Therefore, most readily available and abundant water sources, such as seawater and brackish water, cannot be directly used for hydrogen generation by electrolyzers. Summary of the invention

[0005] According to one aspect, the present application discloses a distillation electrolysis device. The distillation electrolysis device can be used together with a water source. The distillation electrolysis device includes: a cell, a membrane and a baffle. The cell includes: a first electrode, a second electrode and a diaphragm. The first electrode and the second electrode form an operable, paired anode and cathode. The diaphragm is arranged between the first electrode and the second electrode to set a first chamber and a second chamber. The first electrode is arranged in the first chamber, and the second electrode is arranged in the second chamber. The first chamber and the second chamber are fluidically connected to each other only through the diaphragm. The cell is fluidically connected to the water source only through the membrane. The baffle includes a non-porous panel that can be moved relative to the main surface of the membrane to expose a variable area of ​​the membrane to the water source.

[0006] The water transport from the water source through the membrane toward the pool can be at least partially achieved by a vapor pressure difference across the membrane and / or at least partially achieved by an osmotic pressure difference across the membrane. The water transport path from the water source toward the pool can include any of the following: (i) liquid phase transport of liquid water through the membrane in response to the osmotic pressure difference across the membrane, the membrane including a hydrophilic membrane element, and (ii) gas phase transport of water vapor through the membrane in response to the vapor pressure difference across the membrane, the membrane including a hydrophobic membrane element.

[0007] The membrane may be a hydrophilic membrane or a hydrophobic membrane. The membrane may form part of a wall of one or both of the first and second chambers, or the membrane may be disposed outside the cell, wherein the membrane intervenes in each of one or more transport paths from the water source toward the cell. In the case where the membrane is disposed outside the cell, the distillation electrolysis device may include an electrolyte storage tank externally connected to the cell.

[0008] The electrolyser may be operated as an alkaline water electrolyser, a proton exchange membrane water electrolyser and / or an anion exchange membrane water electrolyser.

[0009] The distillation electrolysis device may include a plurality of cells, wherein a pair of anodes and cathodes of any one of the plurality of cells are connected in parallel and / or in series with a pair of anodes and cathodes of another cell of the plurality of cells.

[0010] According to another aspect, the present application discloses a method for water splitting. The method includes providing a feed solution to a pool according to the above. The method may include controlling a variable region of the membrane exposed to a water source by moving a non-porous panel of a baffle relative to the main surface of the membrane, wherein the feed solution is in fluid communication with the water source only through the membrane. The feed solution can be formed by water transmission from the water source through the membrane toward the pool, wherein the transmission includes any one of the following: (i) liquid phase transmission of liquid water through the membrane in response to an osmotic pressure difference across a hydrophilic membrane element, and (ii) gas phase transmission of water vapor in response to a vapor pressure difference across a hydrophobic membrane element.

[0011] According to another aspect, the membrane can be provided with a transfer path extending from the stock solution in the stock channel through the membrane outside the first chamber and directly into the first chamber. The transfer path can be at least partially achieved by an osmotic pressure difference between the stock solution and the first electrolyte solution in the first chamber, wherein the first electrolyte has an osmotic pressure higher than that of the stock solution. Alternatively, the transfer path can be at least partially achieved by a vapor pressure difference across the membrane, the first chamber having a vapor pressure lower than that of the stock channel. The distillation electrolysis device can also include a baffle. The baffle provides a non-porous surface parallel to the main surface of the membrane, wherein the baffle is slidably engaged relative to the membrane.

[0012] The distillation electrolysis device may provide a feed solution in fluid communication with the first chamber only through an active portion of the membrane, wherein the size of the active portion may be adjusted by sliding a baffle relative to the membrane.

[0013] The transport pathway may include liquid phase transport of liquid water through a hydrophilic membrane based on osmotic pressure difference, or may include gas phase transport of water vapor through a hydrophobic membrane based on vapor pressure difference. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Various embodiments of the present disclosure are described below with reference to the following drawings:

[0015] Figure 1A is a schematic diagram showing a cell according to an alkaline water electrolyzer;

[0016] Figure 1B is a schematic diagram showing a cell according to a proton exchange membrane water electrolyzer;

[0017] Figure 1C is a schematic diagram showing a cell according to an anion exchange membrane water electrolyzer;

[0018] Figure 2A is a schematic block diagram illustrating a transmission mechanism according to an embodiment of the present disclosure;

[0019] Figure 2B is a schematic block diagram illustrating a transmission mechanism according to other embodiments of the present disclosure;

[0020] Figure 3 is a perspective view schematically showing a water electrolysis device according to various embodiments of the present disclosure;

[0021] Figure 4A An alkaline water electrolysis device according to an embodiment of the present disclosure is shown, wherein one wall of the anode chamber includes a membrane;

[0022] Figure 4B An alkaline water electrolysis device according to another embodiment of the present disclosure is shown, wherein one wall of the cathode chamber includes a membrane;

[0023] Figure 4CAn alkaline water electrolysis device according to another embodiment of the present disclosure is shown, wherein each of the anode chamber and the cathode chamber includes a wall formed by a membrane;

[0024] Figure 4D A water electrolysis device is shown, wherein the membrane is part of the wall of the anode chamber of a proton exchange membrane water electrolysis cell;

[0025] Figure 4E A water electrolysis device is shown, wherein the membrane is part of the wall of the cathode chamber of an anion exchange membrane water electrolysis cell;

[0026] Figure 5A shows a front view of a water electrolysis device having a movable baffle to provide a controllable active area of ​​a membrane according to various embodiments of the present disclosure;

[0027] Figure 5B Show Figure 5A A side view of a water electrolysis device;

[0028] Figure 5C shows a front view of another water electrolysis device according to various embodiments of the present disclosure, the water electrolysis device having a movable baffle to provide a controllable active area of ​​the membrane;

[0029] Figure 5D Show Figure 5C A side view of the water electrolysis device shown;

[0030] FIG. 6A to FIG. 6C is a schematic diagram showing various embodiments of a water electrolysis device having an external electrolyte storage tank and an external membrane system to replenish the electrolyte with water;

[0031] Fig. 7A A water electrolysis device according to an embodiment of the present disclosure is shown, wherein a plurality of cells are connected in parallel with a closed loop water supply, the water electrolysis device being characterized by having an "AFC" (anode chamber of one unit - feed channel - cathode chamber of the next unit) arrangement;

[0032] Figure 7B A water electrolysis device according to an embodiment of the present disclosure is shown, wherein a plurality of cells are connected in parallel with an open loop water supply, the water electrolysis device being characterized by having an "AFC" (anode chamber of one unit - feed channel - cathode chamber of the next unit) arrangement;

[0033] Fig. 8AA water electrolysis device according to an embodiment of the present disclosure is shown, wherein the plurality of cells are alkaline water electrolyzers (AWE) connected in parallel with a closed loop water supply, wherein the plurality of feed channels are only on the anode chamber side of the AWE;

[0034] Figure 8B A water electrolysis device according to an embodiment of the present disclosure is shown, wherein the plurality of cells are proton exchange membrane water electrolyzers (PEMWE) connected in parallel to a closed loop water supply, wherein the plurality of feed channels are only on the anode chamber side of the PEMWE;

[0035] Fig.9A A water electrolysis device according to an embodiment of the present disclosure is shown, wherein the plurality of cells are alkaline water electrolyzers (AWE) connected in parallel with a closed loop water supply, wherein the plurality of feed solution channels are only on the cathode chamber side of the AWE;

[0036] Fig. 9B A water electrolysis device according to an embodiment of the present disclosure is shown, wherein the plurality of cells are anion exchange membrane water electrolyzers (AEMWE) connected in parallel to a closed loop water supply, wherein the plurality of feed solution channels are only on the cathode chamber side of the AEMWE;

[0037] Fig.10 A water electrolysis device according to an embodiment of the present disclosure is shown, wherein a plurality of cells are connected in parallel with a closed-loop water supply, wherein a plurality of feed liquid channels are connected to the cathode chamber or the anode chamber of each water electrolyzer;

[0038] Fig.11 A water electrolysis device according to an embodiment of the present disclosure is shown, wherein a plurality of cells are connected in parallel with a closed-loop water supply, wherein each raw liquid channel is shared by a plurality of water electrolyzers connected one after the other, and each raw liquid channel supplies the cathode chamber of one water electrolyzer and the anode chamber of another water electrolyzer;

[0039] Fig.12 A water electrolysis device according to another embodiment of the present disclosure is shown, wherein a plurality of cells are connected in parallel with a closed-loop water supply, wherein each raw liquid channel is shared by a plurality of water electrolyzers connected in series, and each raw liquid channel supplies a cathode chamber or an anode chamber of a plurality of water electrolyzers connected in series;

[0040] Fig.13A A water electrolysis device is shown according to an embodiment of the present disclosure, wherein a plurality of cells are connected in series with bipolar assemblies, and wherein a feed channel supplies the anode side of the device;

[0041] Fig. 13B A water electrolysis device is shown according to an embodiment of the present disclosure, wherein a plurality of cells are connected in series with a bipolar assembly, and wherein a feed channel supplies the cathode side of the device;

[0042] Fig. 13C A water electrolysis device is shown in accordance with an embodiment of the present disclosure, wherein a plurality of cells are connected in series with a bipolar assembly, and wherein a feed channel supplies both the anode side and the cathode side of the device;

[0043] Fig.14A A water electrolysis device according to an embodiment of the present disclosure is shown, wherein a plurality of cells are connected in series with bipolar assemblies and in parallel with monopolar assemblies;

[0044] Fig. 14B A water electrolysis device according to an embodiment of the present disclosure is shown, the device comprising a combination of two or more different types of cells, the two or more different types of cells being, for example, an anion exchange membrane water electrolyzer, a proton exchange membrane water electrolyzer, and an alkaline water electrolyzer;

[0045] Fig.15A A scatter plot showing the water influent flux (in liters per square meter of membrane per hour) from multiple sources of simulated wastewater (stock solution) to the electrolytic cell for an electrolyte (draw solution) of 1 mol / liter (M) (molar) NaHCO3 / Na2CO3 buffer solution at different pH (pH=8.0, 9.5 and 11.3) in the electrochemical cell.

[0046] Fig. 15B A scatter plot of water influent flux from multiple water sources of simulated seawater (stock solution) to the cell is shown for an electrolyte (draw solution) of 1 mol / L NaHCO3 / Na2CO3 buffer solution at different pH (pH = 8.0, 9.5 and 11.3) in an electrochemical cell.

[0047] Fig.16 A water electrolysis device having a plurality of detachable modules according to an embodiment of the present disclosure is shown;

[0048] Fig.17 is a schematic flow chart of a water splitting method according to various embodiments of the present disclosure. DETAILED DESCRIPTION

[0049] The following is described in detail in conjunction with the accompanying drawings, in which details and embodiments of the present disclosure are shown for illustrative purposes. Features described in the context of one embodiment may be correspondingly applicable to the same or similar features in other embodiments, even if not explicitly described in other embodiments. Additions and / or combinations and / or substitutions described for features in the context of one embodiment may be correspondingly applicable to the same or similar features in other embodiments.

[0050] In the context of various embodiments, the articles “a,” “an,” and “said” used with respect to features or elements include reference to one or more features or elements.

[0051] In the context of various embodiments, the term "about" or "approximately" as applied to numerical values ​​encompasses both the exact value and a reasonable difference commonly understood in the relevant technical field, for example, within 10% of the specified value.

[0052] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0053] The term "water electrolysis cell" or "cell" used in the present disclosure may be used interchangeably with the term "electrolyzer", "water electrolyzer unit", "water electrolysis device" or "water electrolysis unit". When referring to the present device, the term "distillation electrolysis device" (and / or any cell thereof) and "water electrolysis device" (and / or any cell thereof) may be used interchangeably. According to various embodiments of the present disclosure, the cell 102 includes a cathode 122 and an anode 132. The cathode 122 is disposed in a cathode chamber 120, and the anode 132 is disposed in an anode chamber 130. The cathode chamber 120 and the anode chamber 130 are separated from each other by a diaphragm 150. During operation, a potential difference (e.g., voltage) 104 is provided between the cathode 122 and the anode 132 so that the catalytic electrolysis of water molecules results in the production of hydrogen 20 at the cathode 122 and the production of oxygen 30 at the anode 132. For example, the production of hydrogen 20 and the production of oxygen 30 occur in different chambers 110. In various embodiments, water or stock solution 70 is supplied to one or both chambers 110 .

[0054] Advantageously, and as described below, various embodiments of the water electrolysis device 100 presented herein may be operated by one or more cells 102 of the following types: alkaline water electrolyzers (AWE), proton exchange membrane water electrolyzers (PEMWE), and / or anion exchange membrane water electrolyzers (AEMWE). In the present disclosure, AWE refers to Figure 1AA cell 102 is schematically shown, wherein both the cathode chamber 120 and the anode chamber 130 contain an aqueous solution 90 provided from a water source 80. A membrane 150 between the cathode chamber 120 and the anode chamber 130 serves to separate the hydrogen 20 and oxygen 30 generated in each chamber (at the cathode 122 and the anode 132, respectively) of the plurality of chambers 110. The membrane 150 may also allow the transfer of liquid solutions and ions between the two chambers 110.

[0055] In this disclosure, PEMWE refers to Figure 1B A cell 102 is schematically shown in which only the anode chamber 130 contains an aqueous solution 90 and in which the membrane 150 is a proton exchange membrane (PEM). The PEM separates the two chambers 110 (cathode chamber 120 and anode chamber 130) and only allows the transport of protons from the anode chamber 130 to the cathode chamber 120. The liquid solution 90 will be intercepted by the PEM and retained in the anode chamber 130.

[0056] In this disclosure, AEMWE refers to Figure 1C A cell 102 is schematically shown, wherein only the cathode chamber 120 contains an aqueous solution 90, and wherein the separator 150 is an anion exchange membrane (AEM). The AEM separates the two chambers 110 (cathode chamber 120 and anode chamber 130) and allows the transport of anions (OH⁻) from the cathode chamber 120 to the anode chamber 130. The liquid solution will be intercepted by the AEM and retained in the cathode chamber 120.

[0057] To aid understanding only, the term "water source" 80 may refer to a body of water, such as, but not limited to, a body of water such as a lake, a reservoir, a river, seawater, or the term "water source" 80 may refer to any water source. In the context of the present disclosure, the water source 80 may be any water source, including water of unknown composition and / or not suitable for use in a conventional water electrolyzer. The term "stock solution" or "stock solution" 70 refers to water directed from the water source 80 toward one or more cells 102. In some embodiments, the stock solution 70 may be substantially the same as the water source 80, and in some other embodiments, the stock solution 70 may be a relatively pure form of water source suitable for use in the water electrolysis cell 102. For the present disclosure, depending on the type of water electrolysis device 100, the stock solution 70 may enter the anode chamber 130, the cathode chamber 120, or both the anode chamber 130 and the cathode chamber 120 from one or more stock channels 74. One or more stock channels 74 outside the one or more cells 102 serve to guide the stock solution 70. In some examples, and for ease of reference, the chamber 110 that directly receives the stock solution 70 from the stock channel 74 may be referred to as a "first chamber" 117 or a "drawing chamber". Depending on the type of water electrolysis cell 102, the first chamber 117 may be an anode chamber 130 (a chamber in which an anode 132 is disposed) or a cathode chamber 120 (a chamber in which a cathode 122 is disposed). Alternatively, both the anode chamber 130 and the cathode chamber 120 may serve as a drawing chamber. In some embodiments of the present disclosure, each of the one or more drawing chambers provides a pressure difference (an osmotic pressure difference or other pressure difference) to draw water through the membrane 200 into the cell 102. In some embodiments, the electrolyte or aqueous solution 90 in the drawing chamber may serve as a drawing liquid. In some embodiments, the electrolyte 90 in any one or more of the first chamber 117 and / or the plurality of drawing chambers may be supplied or supplemented by an external membrane system 600 (with or without one or more external electrolyte storage tanks 601).

[0058] According to various embodiments of the present disclosure, the water electrolysis device 100 includes a device configured to provide a continuous supply of sufficiently clean or purified water to one or more water electrolyzers or cells 102 coupled to a water source 80 .

[0059] Figure 2AThe first water transport mechanism is schematically shown, and according to some embodiments of the present water electrolysis device, water can be provided to the water electrolysis cell 102 by the first water transport mechanism. The water electrolysis device 100 of the present disclosure can be directly drawn from a water source 80 or a stock solution 70 that may contain impurities, salt ions, organic materials, etc. The water source 80, such as a natural water body including brackish water, seawater, wastewater, etc., can be used as the stock solution 70. The membrane 200 can be a semi-permeable hydrophilic membrane. The driving force for water transport through the membrane 200 includes a driving force based on the osmotic pressure difference on both sides of the membrane 200. The liquid 90 (also referred to as the draw liquid) in the first chamber 117 has a salinity higher than the salinity of the stock solution 70 (and an osmotic pressure higher than the osmotic pressure of the stock solution 70). The stock solution 70 has a salinity lower than the salinity of the draw liquid 90 (and a corresponding osmotic pressure lower than the osmotic pressure of the draw liquid 90). The osmotic pressure difference between the stock solution 70 and the draw solution 90, on both sides of the membrane 200, drives the pure water from the stock solution 70 to the draw solution 90, along the flow (in liquid phase) of direction 77. The draw solution 90 is also an electrolyte solution 90 having electrolyte ions 91 therein. Examples of electrolyte solutions 90 may include electrolyte ions such as KOH, K2CO3, etc. In some examples, a membrane 200 with a pore size is selected that allows the passage of pure water in liquid phase along direction 77, while blocking the passage of other substances. In some examples, the membrane 200 is selected from a hydrophilic membrane. In some examples, the first water transport mechanism can be described as a forward osmosis process.

[0060] Figure 2BA second water transport mechanism is schematically shown, by which water can be provided to the water electrolysis cell 102 of the present disclosure. The water electrolysis device 100 of the present disclosure can be directly drawn from a water source 80 or a stock solution 70 that may contain impurities, salt ions, organic materials, etc. The water source 80, such as a natural water body including brackish water, seawater, wastewater, etc., can be used as the stock solution 70. The membrane 200 can be a hydrophobic membrane. The driving force for water transport through the membrane 200 includes a driving force based on the vapor pressure difference on both sides of the membrane 200. The draw liquid 90 in the first chamber 117 has a salinity higher than the salinity of the stock solution 70 and a vapor pressure lower than the vapor pressure of the stock solution 70. The stock solution 70 has a salinity lower than the salinity of the draw liquid 90 and a corresponding vapor pressure higher than the vapor pressure of the draw liquid 90. The vapor pressure difference between the water vapor in the stock liquid channel 74 and the water vapor in the first chamber 117 (drawing chamber) on both sides of the membrane 200 drives the flow of pure water (in the gas phase) from the stock liquid channel 74 through the membrane 200 to the first chamber 117 along the direction 79. After being transmitted through the membrane 200, the water vapor condenses into liquid in the first chamber 117. In this case, the membrane 200 is hydrophobic. The first chamber 117 is also an electrolyte solution 90 containing electrolyte ions 91 therein. Examples of the electrolyte solution 90 may include electrolyte ions such as KOH, K2CO3, etc.

[0061] Various embodiments of the water electrolysis device 100 can operate with different selected membranes 200. The membrane 200 can be attached to the draw chamber and can be disposed between the draw chamber and the water source 80. The membrane 200 can be a hydrophobic membrane 220 or a hydrophilic membrane 210. The membrane 200 can alternatively be described as including a hydrophobic membrane element or a hydrophilic membrane element.

[0062] Advantageously, in some embodiments, the water electrolysis device 100 can be operated by a membrane 200, which is selected from a semi-permeable hydrophilic membrane 210 based on polymeric materials, ceramic materials, other inorganic materials (such as carbon materials, metals or metal alloys, etc.) and nanomaterials (such as graphene, graphene oxide, reduced graphene oxide, metal organic frameworks, covalent organic frameworks, etc.). The hydrophilic membrane 210 can be an asymmetric membrane of an integral structure, a thin film composite membrane, a thin film nanocomposite membrane, etc. The hydrophilic membrane 210 can be composed of at least one active layer (dense layer) with a smaller pore size (nanoscale pores), which allows the circulation of water molecules but blocks impurities in the stock solution. Flat sheet membranes are preferred as hydrophilic membranes. Advantageously, the hydrophilic membrane element 210 only allows the penetration of water molecules with higher water permeability, and has a higher rejection rate for all impurities originating from different water sources. Advantageously, the hydrophilic membrane 210 has a high rejection rate for salt ions (such as Ca 2+ Mg 2+ , Cl -The interception rate of the hydrophilic membrane 210 is higher than 90% for all ions in the electrolyte (i.e., the draw solution) and retains them in the anode chamber 130. The hydrophilic membrane 210 can prevent OH from - and H + Permeation from the electrolyte to the stock solution (water source). The interception of impurities in the water source and ions in the electrolytic cell 102 by the hydrophilic membrane 210 originates from the smaller pore size on the active layer (dense layer) of the hydrophilic membrane 210. The hydrophilic membrane 210 can be placed in a manner that the active layer faces the stock solution 70 or the active layer faces the electrolyte solution 90. If the stock solution 70 is not clean and may potentially cause fouling or scaling, it is preferred to place the hydrophilic membrane 210 with its active layer facing away from the cathode chamber 120, the anode chamber 130 or the two chambers 110 to reduce membrane clogging. If the aqueous solution 90 is clean, it is preferred to place the hydrophilic membrane 210 with its active layer facing the cathode chamber 120, the anode chamber 130 or the two chambers 110 to reduce internal concentration polarization and increase the water transmission flux through the hydrophilic membrane 210. The hydrophilic membrane element 210 is selected to have sufficient mechanical strength to resist the hydraulic pressure in the tank 102 and to minimize deformation during recirculation of the aqueous water.

[0063] In some other embodiments, the hydrophobic membrane element 220 may be selected from one or more porous sheets of different types made of one or more hydrophobic materials. Examples of hydrophobic materials include, but are not limited to, polymers (e.g., polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyethylene (PE), etc.), ceramics (after hydrophobic treatment), other inorganic materials (e.g., graphite, activated carbon, metals, etc.), nanomaterials (e.g., carbon nanotubes, graphene, reduced graphene oxide, etc.), and / or one or more composite materials thereof. In this case, water molecules flow through the hydrophobic membrane 220 in the form of water vapor rather than liquid water and condense at the electrolyte solution 90. The hydrophobic membrane element 220 used in the present application may have a porous structure and may be composed of one or more hydrophobic materials. The hydrophobic membrane 220 may include at least one hydrophobic layer. In some embodiments, the hydrophobic membrane 220 may have an asymmetric structure having a hydrophilic support layer and at least one hydrophobic layer. A flat sheet membrane is preferred for this purpose, although not limited thereto. Advantageously, the hydrophobic layer of the hydrophobic membrane 220 may be porous, having a porosity greater than 50% and a pore size in the range of 0.01 μm (micrometer) to 0.5 μm. Advantageously, the water contact angle of the hydrophobic layer may be greater than 120°. The hydrophobic membrane element 220 may be configured to have sufficient mechanical strength to resist the hydraulic pressure in the first chamber 117 / raw liquid channel 74 and to minimize deformation during the recirculation of liquid water. The hydrophobic membrane element 220 is selected as a membrane having the ability to intercept non-volatile compounds such as salt ions, particles, microorganisms and organic matter in an impure water source. The selection of the hydrophobic membrane element 220 is beneficially used to achieve the interception of non-volatile compounds, which is caused by the hydrophobic properties of the membrane. Without being limited by theory, the hydrophobic membrane element 220 can theoretically achieve a 100% interception rate for impurities, which ensures that these impurities do not pass through the membrane and do not contaminate the electrolysis process in the water electrolysis cell 102. The hydrophobic membrane 220 also exhibits efficient retention. Without being limited by theory, in theory, the hydrophobic membrane element 220 can exhibit 100% rejection of the electrolyte ions present in the electrolytic cell (water electrolyzer). - and CO3 2- The electrolyte ions can be retained to ensure the stability and effectiveness of the hydrogen generation process. In practical applications, even if the performance of the hydrophobic membrane element 220 does not achieve a 100% rejection rate for impurities and / or a 100% retention rate for electrolyte ions, the performance of the water electrolysis cell 102 is beneficially and significantly improved compared to conventional systems.

[0064] Figure 31 is a schematic diagram illustrating one aspect of the water electrolysis device 100 or cell 102 of the present disclosure. The membrane 200 forms at least a portion of the wall 115 between the draw chamber / first chamber 117 and the raw liquid channel 74. The water electrolysis device 100 provides water transport in the liquid phase along the direction 77 through the osmotic pressure difference across the hydrophilic membrane element 210, or provides water vapor transport along the direction 79 through the vapor pressure difference across the hydrophobic membrane element 220. The baffle 300 is slidably engaged with the wall 115 of the first chamber 117 and / or the membrane 200 so that the active area of ​​the membrane 200 can be controllably changed. For example, the baffle 300 can be displaced along the direction 303 to cover a portion of the membrane 200. The baffle 300 is non-porous (e.g., includes a non-porous panel 301) so that the surface area of ​​the membrane 200 that is exposed (the area exposed to the liquid phase supply along direction 77 and / or the gas phase supply of water vapor along direction 79) can be controllably set to a desired size. In some examples, the baffle 300 can be set so that the membrane 200 is exposed for only one of the liquid water transmission along direction 77 and the water vapor transmission along direction 79.

[0065] For further explanation, various examples of a water electrolysis apparatus 100 including one or more cells 102 are described in conjunction with the various figures. Figure 4A An alkaline water electrolysis device 100 is shown including a cell 102. A cathode chamber 120 and an anode chamber 130 are completely separated from each other by a diaphragm 150. A cathode 122 is disposed in the cathode chamber 120. An anode 132 is disposed in the anode chamber 130. The cathode chamber 120 is sized to accommodate a cathode electrolyte 92, i.e., an electrolyte on the cathode side. The anode chamber 130 is sized to accommodate an anolyte 93, i.e., an electrolyte on the anode side. The electrolyte 90 including the cathode electrolyte and the anolyte is an aqueous electrolyte suitable for water decomposition. A power source 104 can be connected to supply current (or voltage) to multiple electrodes, i.e., to supply current (or voltage) to the cathode 122 and the anode 132. A continuous source of water (in the form of liquid water and / or water vapor) can be provided through the raw liquid channel 74. In Figure 4A In the example shown, the first chamber 117 is the anode chamber 130. The wall 115 between the first chamber 117 and the stock solution channel 74 includes a membrane 200. The membrane 200 is disposed between a volume of the electrolyte solution 90 and a volume of the stock solution 70. In the example where the membrane 200 is substantially a hydrophobic membrane 220, the membrane 200 only allows the passage of water vapor that is spontaneously generated from the aqueous stock solution 70 in response to a vapor pressure difference across the hydrophobic membrane 220. The water vapor that passes through the hydrophobic membrane 220 condenses into liquid water in the electrolytic cell 102 / electrolyte storage tank 601.

[0066] When the power source 104 is connected to the cathode 122 and the anode 132, the water in the electrolyte 90 can be consumed and decomposed by an electrochemical reaction, which generates hydrogen 20 and oxygen 30 at the cathode 122 and the anode 132, respectively. The hydrogen 20 and the oxygen 30 are separated by the diaphragm 150, and the hydrogen 20 and the oxygen 30 are collected from the device 100 / cell 102 through the outlets 129 / 139 of the cathode chamber 120 and the anode chamber 130, respectively. During the water decomposition process, the water in the electrolyte 90 is continuously consumed. The electrolyte solution 90 advantageously has a higher solute concentration. The osmotic pressure of the electrolyte 90 in the water electrolysis device 100 is higher than that of the water source 80. The water is driven by the osmotic pressure difference between the electrolyte 90 and the water source 80, and is supplied to the anode chamber 130 through the membrane 200. Impurities in the water source 80 are intercepted by the membrane 200 and prevented from entering the anode chamber 130. The solutes in the electrolyte may also be retained in the anode chamber 130 by the membrane 200. If the consumption rate of water in the electrolyte 90 caused by the electrochemical reaction (i.e., the water electrolysis reaction) is equal to the water inflow rate from the water source 80 flowing through the membrane 200, the dynamic balance of the electrolyte 90 is achieved. In this case, the water from the unpurified water source 80 is continuously supplied to the water electrolysis device 100 for the production of higher purity hydrogen and oxygen 20 / 30.

[0067] In one example, the membrane 200 is a forward osmosis (FO) membrane. The water supply by forward osmosis is a passive process, in which water is driven only by the osmotic pressure difference between the electrolyte 90 and the water source 80 without providing external mechanical energy and hydraulic pressure. In another example, the membrane 200 is a hydrophobic membrane 220. The water supply through the hydrophobic membrane 220 is also a passive process, in which water is driven only by the water vapor pressure difference between the electrolyte 90 and the water source 80 without providing external mechanical energy and hydraulic pressure. The water supply process for water decomposition can be sustainable, and the energy consumption of the water supply process is almost zero. The minimum energy used in the water supply process is only used for pumping water and recycling water, which is negligible compared to other pure water manufacturing processes such as reverse osmosis (RO) and electrodeionization. The power supply 104 can be, but is not limited to, various batteries, various types of generators, and fossil fuel-based electricity. It is beneficial to employ sustainable and renewable power sources such as solar cells, wind turbines, and tidal stream generators as the power source 104 .

[0068] When the current 104 is connected to the cathode 122 and the anode 132, an oxygen evolution reaction (OER) with electron generation may occur at the anode 132 (positive electrode), and at the same time, a hydrogen evolution reaction (HER) with electron consumption may occur at the cathode 122 (negative electrode). The main reactions at the anode 132 and the cathode 122 depend on the pH of the electrolyte:

[0069]

[0070] The cathode 122 may be made of any conductive material, such as a metal (e.g., cadmium, titanium, zinc, tin, iron, cobalt, nickel, copper, etc.), an alloy thereof, a carbon material (graphite, activated carbon, etc.), and / or any combination thereof. The anode 132 may be made of nickel, titanium, an alloy of nickel and titanium, and / or any combination thereof. The cathode 122 may include a catalyst for a hydrogen evolution reaction (HER), and the anode 132 may include a catalyst for an oxygen evolution reaction (OER). The catalyst for the hydrogen evolution reaction on the cathode 122 may be a platinum group metal (Pt group metals, PGM) such as platinum, rhodium, and iridium, and a non-platinum group metal (non-PGM) catalyst such as a sulfide, phosphide, carbide, and boride. The catalyst for the oxygen evolution reaction on the anode 132 may be a platinum group metal such as ruthenium, iridium, rhodium, palladium, platinum, and gold, and its oxides including ruthenium dioxide and iridium dioxide. In alkaline electrolytes and neutral electrolytes, non-precious-transition metal oxides, such as cobalt-based materials, nickel-based materials, and iron-based materials, can also be used as oxygen evolution reaction catalysts on the anode 132 .

[0071] The diaphragm 150 may be made of a porous material or a non-porous material. The diaphragm 150 is stabilized in the electrolyte and is capable of separating the gas generated from the cathode chamber 120 from the gas generated from the anode chamber 130 (i.e., hydrogen and oxygen). The porous diaphragm may be a polymer membrane made of, but not limited to, the following materials: polybenzimides, polyphenylene sulphides, sulphonated polymers and composite materials, Zirfon diaphragm (i.e., polyphenylene sulfide fabric symmetrically coated with polymer and zirconium dioxide ZrO2), polyvinylidene Fluoride (PVDF), polytetrafluoroethylene (PTFE), glass fiber membrane, and ceramic membrane. The non-porous diaphragm or dense diaphragm may be an ion-exchange membrane and an ion-solvating membrane. Ion exchange membranes utilize charged functional groups on an organic polymer backbone or an inorganic polymer backbone to allow the transport of certain dissolved ions and block other ions or neutral molecules. Ion exchange membranes can be anion exchange membranes, proton exchange membranes, and cation exchange membranes. Ion solvation membranes can swell when immersed in an aqueous electrolyte and form a polymer / water / electrolyte, uniform ternary electrolyte system. Some examples of ion solvation membranes include polybenzimidazole (PBI) membranes and blend membranes of polysulfone with polyvinylpyrrolidone (PSU-PVP).

[0072] The electrolyte of the water electrolysis device 100 may be one or more of an acidic aqueous solution, a neutral aqueous solution or an alkaline aqueous solution. Advantageously, a neutral or nearly neutral (pH 5 to 9) buffer solution (e.g., H2PO4 - / HPO4 2- 、HCO3 - / CO3 2- ) and alkaline solutions (such as KOH, NaOH, etc.) can be used as electrolytes in alkaline water electrolyzers. For acidic solutions or alkaline solutions, the electrolyte concentration can be 0.1M to 8M, and for buffer solutions, the electrolyte concentration can be 0.1M to 5M. The osmotic pressure of the electrolyte should be higher than that of the water source 1080. Advantageously, the osmotic pressure is greater than 5 bar.

[0073] When the water consumption rate caused by water electrolysis is equal to the water inflow rate flowing from the water source 80 through the membrane 200, one side of the water electrolysis device 100 can be sustainable. The membrane 200 is embedded in the anode chamber 130, and the anode chamber 130 has a frame that can completely replace or partially replace the bipolar plate in the conventional water electrolyzer. On each side of the membrane 200, a spacer 76 is preferably provided to support the membrane 200, establish a flow channel for the raw liquid water or / and the electrolyte solution, and enhance the fluid dynamic conditions (turbulence) on the membrane surface. The water inflow rate flowing through the membrane 200 is determined by the inherent characteristics of the membrane 200, the osmotic pressure difference (for hydrophilic membranes) or the vapor pressure difference (for hydrophobic membranes) between the water source 80 and the electrolyte 90, the active area of ​​the membrane 200 (i.e., the open area of ​​the membrane 200 that is in contact with the aqueous solution) and the fluid dynamic conditions of the water source 80 and the electrolyte 90. The water consumption rate caused by water electrolysis is determined by the current applied to the water electrolyzer 100. Advantageously, the water inflow rate through the membrane 200 may be controlled by the active area of ​​the membrane 200 , the fluid dynamic conditions (eg, cross-flow velocity) of the water source 80 , and the concentration of the electrolyte 90 .

[0074] The water source 80 may be configured to provide different aqueous solutions to the water electrolysis device 100, such as seawater, brackish water, industrial wastewater, municipal wastewater, surface water, groundwater, recycled water, domestic water, tap water, etc. The osmotic pressure of the water source 80 may be about 0.5 bar to about 100 bar (e.g., tap water is less than 1 bar; brackish water is about 7 bar; seawater is about 27 bar; shale gas produced water may reach more than 60 bar).

[0075] When the hydrophobic membrane 220 is used, the water source 80 can advantageously have a temperature higher than that of the electrolyte solution 90, typically in the range of about 30°C to about 90°C. Higher temperatures can effectively increase the water vapor pressure of the water source, which results in an enhanced water vapor pressure difference on both sides of the hydrophobic membrane. The acceleration of the water vapor transmission is conducive to a more efficient fresh water supply for water electrolysis. To achieve a higher water source temperature, low-grade heat sources such as industrial waste heat, thermal energy from solar collectors, and geothermal energy can be utilized. Additionally, an interface heating hydrophobic membrane with an electric heating layer or a photothermal layer combined on the surface can also be used to heat the water source on the membrane surface using electrical energy or solar energy.

[0076] Figure 4B1 shows an alkaline water electrolysis device 100 according to another embodiment of the present disclosure. The water electrolysis device 100 includes a cathode chamber 120, a cathode 122, a diaphragm 150, an anode 132, an anode chamber 130, and a membrane 200. The water source 80 can be drawn from a natural water body. The different components can be as described above. Figure 4A The combination of power source 104, cathode chamber 120, cathode 122, membrane 150, anode 132 and anode chamber 130 may be referred to as a unit or a cell 102. Membrane 200 may be attached to cathode chamber 120 instead of to anode chamber 130.

[0077] Figure 4C 1 shows an alkaline water electrolysis device 100 according to another embodiment of the present disclosure. The water electrolysis device 100 includes a cathode chamber 120, a cathode 122, a diaphragm 150, an anode 132, an anode chamber 130, and two membranes 200, all of which can be referred to above. Figure 4A and Figure 4B The combination of power source 104, cathode chamber 120, cathode 122, diaphragm 150, anode 132 and anode chamber 130 may be referred to as water electrolysis cell 102. Each of the plurality of membranes 200 is attached to one of the cathode chamber 120 and the anode chamber 130, respectively.

[0078] Figure 4D A proton exchange membrane water electrolysis device 100 according to another embodiment of the present disclosure is shown. The water electrolysis device 100 includes a power supply 104, a cathode chamber 120, a cathode 122, a diaphragm 150, an anode 132, an anode chamber 130, and a membrane 200 attached to the anode chamber 130, and the anode chamber 130 is in fluid communication with a water source 80. Each of the power supply 104, the cathode 122, the diaphragm 150, the anode 132, the anode chamber 130, and the membrane 200 can be as described above with reference to Figure 4A The combination of the power supply 104, cathode chamber 120, cathode 122, diaphragm 150, anode 132 and anode chamber 130 may be referred to as a water electrolysis cell 102. In this example, the diaphragm 150 is configured as a proton exchange membrane, which serves as both a diaphragm 150 for the generated gas 20 / 30 and a diaphragm 150 for the electrolyte 90, which is used for the circulation of protons (H⁺) generated on the anode 132. The anode chamber 130 accommodates the anode 132 and the anode electrolyte 93, while the cathode chamber 120 accommodates only the cathode 122 without a liquid cathode electrolyte. In a preferred example, the electrolyte 90 may be an acidic solution including but not limited to an inorganic acid (e.g., H2SO4) and an organic acid, while a neutral solution may also be used. The electrolyte of the neutral solution can avoid acid corrosion, and the ions therein can be highly retained in the anode chamber 130 by the membrane 200.

[0079] Figure 4E An anion exchange membrane water electrolysis device 100 according to another embodiment of the present disclosure is shown. The water electrolysis device 100 includes a power supply 104, a cathode chamber 120, a cathode 122, a diaphragm 150, an anode 132, and an anode chamber 130, and a membrane 200 attached to the cathode chamber 120, and the cathode chamber 120 is in fluid communication with a water source 80. Each of the power supply 104, the cathode chamber 120, the cathode 122, the diaphragm 150, the anode 132, and the membrane 200 can be as described above with reference to Figure 4B The power supply 104, cathode chamber 120, cathode 122, diaphragm 150, anode 132 and anode chamber 130 may be referred to as a cell or unit 102. In this embodiment, the diaphragm 150 is configured as an anion exchange membrane, which serves as both a diaphragm 150 for the generated gas 20 / 30 and a diaphragm 150 for the electrolyte 90, which is used for the circulation of hydroxide ions (OH⁻) generated on the cathode 122. The cathode chamber 120 accommodates the cathode 122 and the cathode electrolyte 92, while the anode chamber 130 accommodates only the anode 132 without a liquid anode electrolyte. In a preferred example, the electrolyte may be a base solution including but not limited to an inorganic base (such as KOH, NaOH, etc.) and an organic base, while a neutral solution may also be used. The alkaline electrolyte can avoid acid corrosion, and the ions therein can be highly retained in the cathode chamber 120 by the membrane 200.

[0080] Any of the above-described water electrolysis devices 100 may also include a baffle 300 attached to its respective membrane 200 . Figure 5A Shown can be included in FIG. 4A to FIG. 4E A front view of a baffle 300 in any water electrolysis device 100 or in an external water supply device 600 as shown, wherein the baffle 300 is configured to control the influx of water flowing through the corresponding membrane 200 (and directly or ultimately entering the water electrolysis device 100) by changing the active area of ​​the corresponding membrane 200. In some embodiments, the baffle 300 is disposed in / is disposed as a portion of the corresponding water electrolysis cell 102. In some embodiments, the baffle 300 is disposed as FIG. 6A to FIG. 6C The water supply device shown (externally connected to the water electrolysis cell 102) is configured as follows: FIG. 6A to FIG. 6C A portion of the water supply apparatus (externally connected to the water electrolysis cell 102) is shown. Figure 5BA side view of the baffle 300 is shown. The baffle 300 can slide in direction 303 to change the open area of ​​the membrane 200 and adjust the water inflow rate flowing through the membrane 200 according to the real-time water consumption rate in the corresponding water electrolysis cell 102. In some embodiments, the water inflow rate flowing through one membrane 200 supplies multiple water electrolysis cells 102, and the water inflow rate flowing through the membrane 200 can be adjusted according to the total real-time water consumption rate of the corresponding multiple water electrolysis cells 102. Preferably, the water permeate flow rate flowing through the membrane 200 should be greater than or equal to the water consumption rate in the corresponding one or more water electrolysis cells 102. If the total water permeate flow rate flowing through the membrane 200 is less than the water consumption rate of the corresponding water electrolysis device 100, additional ultrapure water is required to directly replenish the electrolyte solution 90, or another external membrane device 600 can be constructed to supply water to the corresponding water electrolysis device 100 by using the electrolyte solution 90 as a draw solution and recirculating the electrolyte solution 90 in the external membrane device 600.

[0081] Figure 5C Shown can be included in FIG. 4A to FIG. 4E A front view of a baffle 300 in any water electrolysis device 100 shown or which may be included in an external water supply device 600, wherein the baffle 300 is configured to control the inflow of water into the water electrolysis device cell 102 through the corresponding membrane 200 by changing the active area of ​​the corresponding membrane 200, and the baffle 300 is disposed outside the cell 102 of the corresponding water electrolysis device. Figure 5D 300 is shown in a side view. The baffle 300 may be as described above with reference to Figure 5A and Figure 5B The baffle 300 can slide along the direction 303 to change the open area of ​​the membrane 200 and adjust the water inflow rate through the membrane 200 according to the real-time water consumption rate in the corresponding device.

[0082] FIG. 6A to FIG. 6C A water electrolysis device 100 is shown according to another embodiment of the present disclosure when a hydrophobic membrane 220 is used to supply water to the water electrolysis device 100. In this embodiment, the water electrolysis unit or water electrolysis cell 102 is separated from a water supply unit (external membrane device) 600 having a hydrophobic membrane 220. The water electrolysis unit or water electrolysis cell 102 includes a power supply 104, a cathode chamber 120, a cathode 122, a diaphragm 150, an anode 132, and an anode chamber 130. The water supply unit 600 includes a membrane 200 disposed between a water source 80 and an electrolyte chamber 610 (or an electrolyte storage tank 601), and the electrolyte chamber 610 serves as an extraction chamber to extract the stock solution from both sides of the membrane 200. The cathode chamber 120 or the anode chamber 130 or both the cathode chamber 120 and the anode chamber 130 of the cell 102 are connected to the electrolyte storage tank 601 through a plurality of pipes 690, as shown in FIG. Fig. 6A , Figure 6B and Figure 6C As shown. Continuously or intermittently use a circulation pump to circulate the electrolyte in the electrolyte storage tank 601 between the cathode chamber 120 and / or the anode chamber 130 and the electrolyte storage tank 601, so as to maintain the electrolyte concentration in the cathode chamber 120 and / or the anode chamber 130 at a relatively stable level. Simultaneously, the electrolyte chamber 610 of the water supply unit 600 is also connected to the electrolyte storage tank 601, and the electrolyte is also circulated between them through multiple pipelines 690 and the circulation pump. Due to the lower water vapor pressure of the electrolyte in the electrolyte chamber 610, the water vapor generated from the water source 80 with a higher water vapor pressure can be transmitted through the hydrophobic membrane 220 and condensed into liquid water in the electrolyte chamber 610. Subsequently, water will circulate to the electrolyte storage tank 601 together with the electrolyte, and then to the pool 102, thereby further supplying water for water electrolysis. The membrane 200 can have different configurations, such as a flat sheet configuration, a hollow fiber configuration, and a tubular configuration. The membrane 200 can be housed in different types of modules, such as a plate-and-frame module, a hollow fiber module, a tubular module, a spiralwound module. The membrane module can be immersed in an external feedwater source, or the external feedwater can be circulated through the membrane module.

[0083] Any of the water electrolysis devices 100 described above may alternatively be configured to include two or more cells 102 for large-scale hydrogen production from an unpurified water source 80. Fig. 7A As shown, the water electrolysis device 100 includes a plurality of cells 102 connected in parallel and in an arrangement of "anode chamber of one unit - feed liquid channel - cathode chamber of the next unit" (AFC arrangement), and a closed-loop water supply established by a pipeline 190 in fluid communication with a water source 80. The water electrolysis device 100 also includes a plurality of feed liquid channels 74 disposed between each cathode chamber 120 and each anode chamber 130. The pipeline 190 can transport different aqueous solutions from the water source 80 to each cathode chamber 120 and the corresponding adjacent anode chamber 130 through each feed liquid channel 74. The water from the water source 80 can be driven by the osmotic pressure difference across each membrane 200, and thus supplied to each cathode chamber 120 and each anode chamber 130 through each membrane 200, as shown in FIG. Fig. 7A The aqueous solution, also referred to as the raw liquid stream, can be recirculated back to the water source 80 via line 190 .

[0084] A plurality of spacers 76 may be disposed in a plurality of stock channels 74 to avoid direct contact between two adjacent membranes 200 of two adjacent pools 102 and to establish a flow channel for the water source 80. Different geometric shapes of the spacers 76 may affect the fluid / flow dynamics (e.g., flow velocity, turbulence, etc.) and mass transfer of the stock flow in the stock channel 74. Different types of spacers 76 are suitable for the present disclosure, including mesh spacers, diamond-shaped spacers, ladder spacers, and any other type of spacers that can provide flow channels, enhance mixing and turbulence, and change the fluid dynamic conditions in the stock channel 74.

[0085] The water inflow rate from the raw liquid channel 74 through the membrane 200 to the cell 102 can also be controlled by the active area of ​​the membrane 200, the fluid dynamic conditions of the water source 80, and the concentration of the electrolyte. For example, the baffle 300 (e.g., attached to the membrane 200) can be used to control the water consumption rate in the water electrolysis unit or water electrolysis cell 102 in real time. Figure 5A or Figure 5C As shown in FIG. 1 ), the water inflow rate through the membrane 200 is controlled by changing the open area (active area or exposed area) of the membrane 200. The cross-flow rate and velocity of the aqueous solution can be adjusted to change the degree of concentration polarization, which helps to adjust the water flux.

[0086] exist Figure 7B In another example shown, the water electrolysis device 100 includes membrane-embedded water electrolysis units or water electrolysis cells 102, which are connected in parallel and in an "anode chamber of one unit-raw liquid channel-cathode chamber of the next unit" (AFC configuration). The water electrolysis device 100 includes a connection to an open-loop water supply, which is established by a pipeline 190 in fluid communication with a water source 80. The raw liquid flow can be discharged directly from the device 100 after flowing through the raw liquid channel 74 without being circulated back to the water source 80.

[0087] Fig. 8A A water electrolysis device 100 according to another embodiment of the present disclosure is shown. A plurality of membrane-embedded alkaline water electrolysis (AWE) cells 102 including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150, and a plurality of anodes 132 are connected in parallel with a plurality of feed channels 74 contacting the anode chambers 130 of each cell. The water electrolysis device 100 includes a closed loop water supply established by a conduit 190 in fluid communication with a water source 80. Figure 8BA water electrolysis device 100 according to another embodiment of the present disclosure is shown. A plurality of membrane-embedded proton exchange membrane water electrolysis cells (PEMWE) 102 including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150, and a plurality of anodes 132 are connected in parallel with a plurality of feed channels 74 contacting the plurality of anode chambers 130 of the plurality of cells. The water electrolysis device 100 includes a closed loop water supply established by a pipeline 190 in fluid communication with a water source 80.

[0088] Fig.9A A water electrolysis device 100 according to an embodiment of the present disclosure is shown. A plurality of membrane-embedded alkaline water electrolysis (AWE) cells 102 including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150, and a plurality of anodes 132 are connected in parallel with a plurality of feed channels 74 of the plurality of cathode chambers 120 contacting the plurality of water electrolysis cells. The water electrolysis device 100 includes a closed loop water supply established by a conduit 190 in fluid communication with a water source 80. Fig. 9B A water electrolysis device 100 according to an embodiment of the present disclosure is shown. A plurality of membrane-embedded anion exchange membrane water electrolysis (AEMWE) cells 102 including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150 configured as anion exchange membranes, and a plurality of anodes 132 are connected in parallel with a plurality of feed channels 74 contacting the plurality of cathode chambers 120 of the plurality of cells. The device 100 includes a closed loop water supply established by a conduit 190 in fluid communication with a water source 80.

[0089] Fig.10 A water electrolysis device 100 according to an embodiment of the present disclosure is shown. A plurality of membrane-embedded water electrolysis units or water electrolysis cells 102 including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150, and a plurality of anodes 132 are connected in parallel with a plurality of feed liquid channels 74 connected to the cathode chamber 120 or the anode chamber 130 of each water electrolysis unit or water electrolysis cell 102. The water electrolysis device 100 includes a closed-loop water supply established by a pipeline 190 in fluid communication with a water source 80.

[0090] Fig.11 A water electrolysis device 100 according to an embodiment of the present disclosure is shown. A plurality of membrane-embedded water electrolysis units or water electrolysis cells 102 including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150, and a plurality of anodes 132 are connected in parallel with a plurality of feed channels 74 on both the plurality of cathode chambers 120 and the plurality of anode chambers 130 of the plurality of water electrolysis units or water electrolysis cells 102. The device 100 includes a closed-loop water supply established by a conduit 190 in fluid communication with a water source 80.

[0091] Fig.12A device 100 according to an embodiment of the present disclosure is shown. A plurality of membrane-embedded water electrolysis units 102 including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150, and a plurality of anodes 132 are arranged in a manner that the anode chambers 130 are adjacent to the anode chambers 130, and are connected to a plurality of feed liquid channels 74 on both the plurality of cathode chambers 120 and the plurality of anode chambers 130 of the plurality of water electrolysis units or water electrolysis cells 102. Each feed liquid channel 74 is connected only to the plurality of anode chambers 130 or the plurality of cathode chambers 120 of the plurality of adjacent water electrolysis units 102. The device 100 includes a closed-loop water supply established by a pipeline 190 in fluid communication with a water source 80.

[0092] Fig.13A A water electrolysis device 100 according to an embodiment of the present disclosure is shown. A plurality of membrane-embedded water electrolysis units or water electrolysis cells 102 including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150, and a plurality of anodes 132 are connected in series with a bipolar assembly. A raw liquid channel 74 is connected to the outermost anode chamber 130 in the plurality of cells 102. One side of each electrode in the plurality of cathodes 122 and the plurality of anodes 132 serves as the cathode 122 of one cell 102, and the other side serves as the anode 132 of an adjacent cell 102. The diaphragm 150 is disposed between the anode 132 and the cathode 122 in each cell 102 to separate the oxygen 30 and the hydrogen 20 generated from the plurality of electrodes. The water electrolysis device 100 includes a closed-loop water supply established by a pipeline 190 in fluid communication with a water source 80.

[0093] Fig. 13B A water electrolysis device 100 according to an embodiment of the present disclosure is shown. A plurality of membrane-embedded water electrolysis units or water electrolysis cells 102 including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150, and a plurality of anodes 132 are similar to those described above with reference to Fig.13A The bipolar assemblies are connected in series. The feed channel 74 is connected to the outermost cathode chamber 120 of the plurality of water electrolysis units or water electrolysis cells 102. The water electrolysis device 100 includes a closed loop water supply established by a pipeline 190 in fluid communication with a water source 80.

[0094] Fig. 13C A water electrolysis device 100 according to an embodiment of the present disclosure is shown. A plurality of membrane-embedded water electrolysis units or water electrolysis cells 102 including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150, and a plurality of anodes 132 are similar to those described above with reference to Fig.13A The bipolar assemblies are connected in series. The feed channel 74 is connected to both the outermost cathode chamber 120 and the outermost anode chamber 130 of the plurality of water electrolysis units or cells 102. The water electrolysis device 100 includes a closed loop water supply established by a conduit 190 in fluid communication with a water source 80.

[0095] Fig.14A A water electrolysis device 100 according to an embodiment of the present disclosure is shown. A plurality of membrane-embedded water electrolysis units or water electrolysis cells 102, including a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, a plurality of diaphragms 150, and a plurality of anodes 132, are connected in series with the bipolar assembly and in parallel with the monopolar assembly. The water electrolysis device 100 includes a closed-loop water supply established by a pipeline 190 in fluid communication with a water source 80.

[0096] Fig. 14B A water electrolysis device 100 according to an embodiment of the present disclosure is shown. A plurality of membrane-embedded water electrolysis units or water electrolysis cells 102 include a plurality of membranes 150 in the form of anion exchange membrane diaphragms, proton exchange membrane diaphragms, or alkaline water diaphragms. The plurality of cells 102 further include a plurality of cathode chambers 120, a plurality of anode chambers 130, a plurality of cathodes 122, and a plurality of anodes 132. The water electrolysis device 100 includes a closed-loop water supply established by a conduit 190 in fluid communication with a water source 80.

[0097] The water electrolysis device 100 of the present disclosure collects water from a water source that supplies wastewater or seawater as a stock solution. The components of the simulated wastewater and simulated seawater are listed in Table 1. Fig.15A and Fig. 15B The flow rate of water from the simulated wastewater and simulated seawater sources (stock solution) into the water electrolysis device of the present invention in liters per square meter of membrane per hour (L m -2 h -1 ) in units of water inflow flux. The electrolyte (draw solution) in the (electrochemical) cell is a 1M NaHCO3 / Na2CO3 buffer solution with different pH values ​​(pH=8.0, 9.5, and 11.3). Multiple water inflow fluxes are calculated by weight changes of the water electrolysis device automatically recorded by a digital balance. The device 100 can effectively collect pure water from two water sources. Multiple pure water fluxes using simulated wastewater as the water source are about 4L m -2 h -1 to about 6.5L m -2 h -1 (liters per square meter of FO membrane per hour). Multiple pure water fluxes using simulated seawater as the water source were around 1.1 L m -2 h -1 About 1.5L m -2 h -1The water flux into the water electrolysis device can be further adjusted by changing the composition and concentration of the electrolyte (draw solution), the hydrodynamic conditions of the source water (e.g., cross-flow velocity, spacer type), the solution temperature, and the type of FO membrane.

[0098] Table 1 Composition of simulated wastewater and simulated seawater

[0099]

[0100] According to another aspect, the present disclosure also provides a modular water electrolysis device. Fig.16 1 shows a water electrolysis device 100 having a plurality of separable modules 700 according to an embodiment of the present disclosure. Each module 700 includes a frame 704 and a plate 706 surrounded by the frame 704. An outlet 708 for gas is provided on each frame 704. The plate 706 may be a cathode, an anode or a diaphragm. The plurality of modules 700 may be connected to a water source and a power source ( Fig.16 The device 100 is easily assembled and disassembled, for example by slotting the appropriate panels or removing one or more panels for cleaning and / or other maintenance.

[0101] According to another aspect, and if Fig.17 Schematically, the present disclosure also provides a water splitting method 900. The method 900 includes providing a potential difference between a cathode-anode pair, for example, by electrically coupling the cathode and the anode via a power supply 104, wherein the cathode 122 and the anode 132 are electrically isolated by a separator 150 disposed between the cathode 122 and the anode 132. The method 900 includes: step 910, in which water is provided from a water source 80 in fluid communication with at least one of the cathode 122 and the anode 132 through a membrane 200 disposed between the water source 80 and at least one of the cathode 122 and the anode 132 (the membrane 200 allows water to permeate from a stock solution 70 provided by the water source 80 to at least one of the cathode 122 and the anode 132); and current is applied between the cathode 122 and the anode 132 through a power source for electrochemically decomposing water contacting the cathode 122 and the anode 132, thereby forming hydrogen 20 on the cathode 122 and oxygen 30 on the anode 132, and separating the hydrogen 20 from the oxygen 30 through the membrane 150. Each of the cathode 122, the anode 132, the membrane 150, the power source 104, and the membrane 200 can be disposed relative to the water source 80 according to any of the above-described embodiments.

[0102] According to another aspect, the method 900 of the present disclosure includes providing a stock solution 70 to a cell 102, and step 920, in which a variable portion of the membrane 200 exposed to a water source 80 is controlled. The cell 102 includes a first electrode and a second electrode, wherein the first electrode and the second electrode form an operable, paired anode 132 and cathode 122. The cell 102 includes a diaphragm 150. The diaphragm 150 is disposed between the first electrode and the second electrode to define a first chamber 117 / 110 and a second chamber 118 / 110. The first electrode is disposed in the first chamber 117 / 110, and the second electrode is disposed in the second chamber 118 / 110. The first chamber 117 and the second chamber 118 are in fluid communication with each other only through the diaphragm 150. The control of the variable portion of the membrane 200 exposed to the water source 80 can be performed by moving the imperforate panel 301 of the baffle 300 relative to the major surface of the membrane 200. The stock solution 70 is in fluid communication with the water source 80 only through the membrane 200 .

[0103] In some embodiments, the stock solution 70 is formed by transporting water from a water source 80 through the membrane 200 toward the tank 102, wherein the transport includes any one of: (i) liquid phase transport 77 of liquid water through the membrane in response to an osmotic pressure difference across the hydrophilic membrane element 210, and (ii) gas phase transport 79 of water vapor in response to a vapor pressure difference across the hydrophobic membrane element 220. The step 930 of generating hydrogen 20 and oxygen 30 is based on the water received through the above-mentioned water transport 77 / 79.

[0104] According to various embodiments of the present disclosure, a water electrolysis device 100 for use with a stock solution 70 includes: a first electrode; a second electrode; a diaphragm 150; and a membrane 200. The first electrode and the second electrode form an operable, paired anode 132 and cathode 122. The diaphragm 150 is disposed between the first electrode and the second electrode to define a first chamber 117 / 110 and a second chamber 118 / 110. The first electrode is disposed in the first chamber, and the second electrode is disposed in the second chamber. The first chamber 117 and the second chamber 118 are in fluid communication with each other only through the diaphragm 150. The membrane 200 is a portion of the wall 115 of the first chamber. The membrane 200 is provided with a transmission path. The transmission path extends from the stock solution 70 in the stock channel 74, outside the first chamber 117, through the membrane 200, and directly into the first chamber 117. The transmission path is at least partially realized by the osmotic pressure difference between the stock solution and the first electrolyte solution in the first chamber, on both sides of the hydrophilic membrane 210. The first electrolyte has an osmotic pressure higher than that of the stock solution 70. The transport path includes liquid phase transport of liquid water along direction 77 through the hydrophilic membrane 210 based on the osmotic pressure difference. The hydrophilic membrane 210 may be composed of at least one active layer (dense layer) having a smaller pore size (nanoscale) that only allows water molecules to flow. The hydrophilic membrane 210 can intercept impurities in the stock solution and prevent electrolyte ions from passing through the membrane 200. In another example, the transport path is at least partially realized by the vapor pressure difference on both sides of the hydrophobic membrane 220, and the first chamber has a lower vapor pressure than the stock channel 74. The transport path includes water vapor transport along direction 79 through the hydrophobic membrane 220 based on the vapor pressure difference. The hydrophobic membrane 220 may include at least one hydrophobic layer, which is characterized by having a water contact angle higher than 120°. The hydrophobic membrane 220 may be characterized by having a porosity higher than 50% and a pore size in the range of 0.01μm to 0.5μm. The membrane 200 may be configured to prevent non-volatile compounds in the stock solution from passing through the membrane 200 , and the membrane 200 may be configured to prevent electrolyte ions from passing through the membrane 200 .

[0105] The water electrolysis device 100 includes a baffle 300 providing a non-porous surface 301 parallel to a major surface of the membrane 200 , wherein the baffle 300 is slidably engaged relative to the membrane 200 .

[0106] The baffle plate 300 may be slidably engaged on a major surface facing the raw liquid passage 74. The baffle plate 300 may be slidably engaged on a major surface facing away from the raw liquid passage 74.

[0107] The baffle 300 can be controllably slidable to expose a variable region of the membrane 200 to the feed liquid channel 74 .

[0108] The dope solution 70 is in fluid communication with the first chamber 117 only through the active portion of the membrane 200 , wherein the size of the active portion can be adjusted by sliding the baffle 300 relative to the membrane 200 .

[0109] The membrane 150 may include a proton exchange membrane, wherein the first electrode is the anode 132. The membrane 150 may include an anion exchange membrane, wherein the first electrode is the cathode 122.

[0110] The water electrolysis device 100 in operation responds to the current provided to the cathode 122 and the anode 132 to electrochemically decompose water contacting the cathode 122 and the anode 132, thereby generating hydrogen 20 at the cathode 122 and oxygen 30 at the anode 132, wherein the hydrogen 20 and the oxygen 30 are separated by the membrane 150.

[0111] In some embodiments, the first electrode is a cathode 122. In other embodiments, the first electrode is an anode 132.

[0112] The water electrolysis device 100 may further include a second membrane 200. The second membrane 200 may be a portion of the second wall 115 of the second chamber 118. The second membrane 200 may be provided with a second transport path extending from the stock solution 70 in the second stock channel 74, outside the second chamber 118, through the second membrane 200, and directly into the second chamber 118. The second transport path 72 is at least partially achieved by an osmotic pressure difference between the stock solution 70 and the second electrolyte solution in the second chamber 118, wherein the second electrolyte has a higher osmotic pressure than the stock solution 70.

[0113] According to various embodiments, the device 100 includes a plurality of water electrolysis cells 102. A pair of anodes 132 and cathodes 122 of one water electrolysis cell 102 in the plurality of water electrolysis cells 102 are connected in parallel with a pair of anodes 132 and cathodes 122 of another water electrolysis cell 102 in the plurality of water electrolysis cells 102. The device 100 may include a feed liquid channel 74, which is in fluid communication with the first chambers 117 of each of two water electrolysis cells 102 in the plurality of water electrolysis cells 102.

[0114] According to various embodiments, the device 100 includes a plurality of water electrolysis cells 102. Two or more pairs of anodes 132 and cathodes 122 are connected in series. The feed liquid channel 74 is in fluid communication with one or both end first chambers of the plurality of water electrolysis cells 102.

[0115] According to various embodiments of the present disclosure, method 900 includes: step 910, in which a stock solution is provided to a membrane of a water electrolysis device; and a current is applied to a paired anode and cathode of the water electrolysis device, wherein a transport path 72 from the stock solution through the membrane 200 and directly into the first chamber 117 is at least partially realized by one or both of an osmotic pressure difference across the hydrophilic membrane 210 and a vapor pressure difference across the hydrophobic membrane 220, and wherein the first electrolyte has an osmotic pressure higher than that of the stock solution, and wherein the first chamber 117 has a vapor pressure lower than that in the stock solution channel 74. Method 900 may also include: step 920, in which a size of an active area of ​​the membrane 200 is changed by sliding the non-porous baffle 300 relative to the membrane 200.

[0116] According to one aspect, various embodiments of the present disclosure include a water electrolysis device or a distillation electrolysis device 100 for use with a water source 80. The distillation electrolysis device 100 includes: a cell 102, a membrane 200, and a baffle 300. The cell 102 includes: a first electrode, a second electrode, and a diaphragm 150. The first electrode and the second electrode form an operable, paired anode 132 and cathode 122. The diaphragm 150 is disposed between the first electrode and the second electrode to define a first chamber 117 and a second chamber 118. The first electrode is disposed in the first chamber 117, and the second electrode is disposed in the second chamber 118. The first chamber 117 and the second chamber 118 are in fluid communication with each other only through the diaphragm 150. The cell 102 is in fluid communication with the water source 80 only through the membrane 200. The baffle 300 includes a non-porous panel 301 that is movable relative to the main surface of the membrane 200 to expose a variable region of the membrane 200 to the water source 80.

[0117] In some embodiments, water transport from water source 80 through membrane 200 toward tank 102 is achieved at least in part by a vapor pressure differential across membrane 200 .

[0118] In some embodiments, water transport from water source 80 through membrane 200 toward tank 102 is achieved at least in part by an osmotic pressure difference across membrane 200 .

[0119] In some embodiments, the water transport path 72 from the water source 80 toward the pool 102 includes any one of the following: (i) liquid phase transport of liquid water through the membrane 200 along direction 77 in response to the osmotic pressure difference on both sides of the membrane 200, and the membrane 200 includes a hydrophilic membrane element 210, and (ii) gas phase transport of water vapor through the membrane 200 along direction 79 in response to the vapor pressure difference on both sides of the membrane 200, and the membrane 200 includes a hydrophobic membrane element 220.

[0120] In some embodiments, the membrane 200 includes at least one hydrophilic membrane element 210. The at least one hydrophilic membrane element 210 may include at least one active layer having nanoscale pores configured to allow passage of only water molecules.

[0121] In some embodiments, membrane 200 includes at least one hydrophobic membrane element 220. At least one hydrophobic membrane element 220 may include at least one hydrophobic layer characterized by having a water contact angle greater than 100°.

[0122] In some embodiments, at least one hydrophobic membrane element 220 is characterized by having a porosity greater than 50% and a pore size in the range of 0.01 μm to 0.5 μm.

[0123] In some embodiments, the membrane 200 can form a portion of the wall 115 of one or both of the first chamber 117 and the second chamber 118, wherein the membrane 200 is respectively involved in each of the one or more transmission paths 72 from the water source 80 to the one or more chambers in the first chamber 117 and the second chamber 118.

[0124] In some embodiments where the membrane 200 is disposed outside of the tank 102 , the membrane 200 is externally connected to the tank 102 , wherein the membrane 200 is interposed in each of the one or more transport paths 72 from the water source 80 toward the tank 102 .

[0125] In some embodiments, the water electrolysis device or distillation electrolysis device 100 may include an electrolyte storage tank 601, which is arranged outside the cell 102 and in one or more transmission paths 72, wherein the electrolyte storage tank 601 is connected to the water source 80 fluid only through the membrane 200.

[0126] In some embodiments, the membrane 200 can be configured to prevent the transport of impurities through the membrane 200. In some embodiments, the membrane 200 can be configured to prevent the transport of electrolyte ions 91 through the membrane 200.

[0127] In some embodiments, the non-porous panel 301 can be parallel to a major surface of the membrane 200, wherein the panel 301 can be slidably engaged relative to the membrane 200. In some embodiments, the panel 301 can be slidably engaged on a major surface facing the water source 80. In some embodiments, the panel 301 can be slidably engaged on a major surface facing away from the water source 80.

[0128] In some embodiments, cell 102 may operate as an alkaline water electrolyzer. In some embodiments, membrane 150 comprises a proton exchange membrane, and cell 102 may operate as a proton exchange membrane water electrolyzer. In some embodiments, membrane 150 comprises an anion exchange membrane, and cell 102 may operate as an anion exchange membrane water electrolyzer.

[0129] In some embodiments, the operating distillation electrolysis device 100 responds to the current 104 provided to the cathode 122 and the anode 132, wherein water contacting the cathode 122 and the anode 132 is electrochemically decomposed to generate hydrogen 20 at the cathode 122 and oxygen 30 at the anode 132, and the hydrogen 20 and the oxygen 30 are separated by the membrane 150.

[0130] According to another aspect, according to various embodiments of the present disclosure, a water electrolysis device or distillation electrolysis device 100 for use with a water source 80 includes a plurality of cells 102, a membrane 200, and a baffle 300. Each cell 102 of the plurality of cells 102 includes: a first electrode, a second electrode, and a diaphragm 150. The first electrode and the second electrode form an operable, paired anode 132 and cathode 122. The diaphragm 150 is disposed between the first electrode and the second electrode to define a first chamber 117 and a second chamber 118. The first electrode is disposed in the first chamber 117, and the second electrode is disposed in the second chamber 118. The first chamber 117 and the second chamber 118 are in fluid communication with each other only through the diaphragm 150. The plurality of cells 102 are in fluid communication with the water source 80 only through the membrane 200. The baffle 300 includes a non-porous panel 301 that is movable relative to the main surface of the membrane 200 to expose a variable region of the membrane 200 to the water source 80.

[0131] According to some embodiments, water transport from the water source 80 through the membrane 200 toward the plurality of pools 102 is at least partially enabled by a vapor pressure differential across the membrane 200. According to some embodiments, water transport from the water source 80 through the membrane 200 toward the plurality of pools 102 is at least partially enabled by an osmotic pressure differential across the membrane 200. According to some embodiments, the membrane 200 includes a hydrophilic membrane element 210, which is configured to enable liquid phase transport of liquid water from the water source 80 toward the plurality of pools 102 in direction 77 in response to an osmotic pressure differential across the membrane 200. According to some embodiments, the membrane 200 includes a hydrophobic membrane element 220, which is configured to enable gas phase transport of water vapor from the water source 80 toward the plurality of pools 102 in direction 79 in response to a vapor pressure differential across the membrane 200.

[0132] According to some embodiments, the paired anodes 132 and cathodes 122 of any one of the plurality of cells 102 are connected in parallel with the paired anodes 132 and cathodes 122 of another of the plurality of cells 102. According to some embodiments, the paired anodes 132 and cathodes 122 of any one of the plurality of cells 102 are connected in series with the paired anodes 132 and cathodes 122 of another of the plurality of cells 102.

[0133] According to some embodiments, the membrane 200 forms a portion of a wall 115 of at least one of the plurality of pools 102, wherein the wall 115 is a portion of one or both of the first chamber 117 and the second chamber 118, and wherein the membrane 200 is interposed in each of the one or more transport paths 72 from the water source 80 toward the plurality of pools 102.

[0134] According to some embodiments, the distillation electrolysis device 100 further includes an electrolyte storage tank 601, wherein the electrolyte storage tank 601 is disposed outside the multiple cells 102 and is fluidly connected to the water source 80 only through the membrane 200, and wherein the membrane 200 is disposed outside the multiple cells 102 and is involved in each of the one or more transmission paths 72 from the water source 80 toward the multiple cells 102.

[0135] According to another aspect, an embodiment of the present disclosure provides a method 900 for water splitting. The method 900 includes step 910, in which a stock solution is provided to a cell 102. The cell 102 includes a first electrode, a second electrode, and a diaphragm 150. The first electrode and the second electrode form an operable, paired anode 132 and cathode 122. The diaphragm 150 is disposed between the first electrode and the second electrode to define a first chamber 117 and a second chamber 118. The first electrode is disposed in the first chamber 117, and the second electrode is disposed in the second chamber 118. The first chamber 117 and the second chamber 118 are in fluid communication with each other only through the diaphragm 150. The method 900 includes step 920, in which a variable region of the membrane 200 exposed to the water source 80 is controlled by moving the imperforate panel 301 of the baffle 300 relative to the major surface of the membrane 200, wherein the stock solution 70 is in fluid communication with the water source 80 only through the membrane 200.

[0136] In various embodiments, the stock solution 70 is formed by transporting water from a water source 80 through the membrane 200 toward the tank 102, wherein the transport includes any one of: (i) liquid phase transport of liquid water through the membrane in direction 77 in response to an osmotic pressure difference across the hydrophilic membrane element 210, and (ii) vapor phase transport of water vapor in direction 79 in response to a vapor pressure difference across the hydrophobic membrane element 220. Water splitting 930 is based on the stock solution 70 supplied by the above transport.

[0137] All examples of devices, methods, materials or products described herein are presented for the purpose of explanation and aiding understanding, and are not intended to be limiting or exhaustive. Those of ordinary skill in the art may make modifications without departing from the scope of the invention.

Claims

1. A distillation electrolysis device for use with a water source, the distillation electrolysis device comprising: A pool, the pool comprising: a first electrode; a second electrode, the first electrode and the second electrode forming an operational, paired anode and cathode; and a diaphragm disposed between the first electrode and the second electrode to define a first chamber and a second chamber, the first electrode being disposed in the first chamber, and the second electrode being disposed in the second chamber, the first chamber and the second chamber being in fluid communication with each other only through the diaphragm; a membrane, said reservoir being in fluid communication with said water source only through said membrane; and A baffle, wherein the baffle comprises an imperforate panel movable relative to a major surface of the membrane to expose a variable region of the membrane to the water source.

2. A distillation electrolysis apparatus according to claim 1, wherein the transport of water from the water source through the membrane towards the cell is at least partially achieved by a vapor pressure difference across the membrane.

3. The distillation electrolysis apparatus of claim 1, wherein the transport of water from the water source through the membrane toward the cell is at least partially achieved by an osmotic pressure difference across the membrane.

4. The distillation electrolysis device according to claim 1, wherein the water transmission path from the water source toward the pool includes any one of the following: (i) liquid phase transmission of liquid water through the membrane in response to the osmotic pressure difference between the two sides of the membrane, and the membrane includes a hydrophilic membrane element, and (ii) gas phase transmission of water vapor through the membrane in response to the vapor pressure difference between the two sides of the membrane, and the membrane includes a hydrophobic membrane element.

5. The distillation electrolysis device according to any one of claims 1 to 4, wherein the membrane comprises at least one hydrophilic membrane element, the at least one hydrophilic membrane element comprises at least one active layer, and the at least one active layer has nanoscale pores configured to allow only water molecules to flow.

6. The distillation electrolysis device according to any one of claims 1 to 4, wherein the membrane comprises at least one hydrophobic membrane element, the at least one hydrophobic membrane element comprises at least one hydrophobic layer, and the at least one hydrophobic layer is characterized by having a water contact angle greater than 100°.

7. The distillation electrolysis device according to claim 6, wherein the at least one hydrophobic membrane element is characterized by having a porosity higher than 50% and a pore size in the range of 0.01 μm to 0.5 μm.

8. A distillation electrolysis device according to claim 5 or 6, wherein the membrane forms a part of the wall of one or both of the first chamber and the second chamber, wherein the membrane is involved in each of the one or more transmission paths from the water source to the one or more chambers in the first chamber and the second chamber.

9. A distillation electrolysis device according to claim 5 or 6, wherein the membrane is arranged outside the cell, and wherein the membrane is externally connected to the cell, and wherein the membrane is involved in each of one or more transmission paths from the water source toward the cell.

10. The distillation electrolysis device according to claim 9, further comprising an electrolyte storage tank, wherein the electrolyte storage tank is arranged outside the electrolysis cell and in the one or more transmission paths, wherein the electrolyte storage tank is connected to the water source fluid only through the membrane.

11. The distillation electrolysis apparatus according to any one of claims 1 to 10, wherein the membrane is configured to prevent the transport of impurities through the membrane.

12. The distillation electrolysis apparatus according to any one of claims 1 to 11, wherein the membrane is arranged to prevent transport of electrolyte ions through the membrane.

13. The distillation electrolysis apparatus according to any one of claims 1 to 12, wherein the imperforate panel is parallel to the major surface of the membrane, and wherein the baffle is slidably engaged relative to the membrane.

14. The distillation electrolysis apparatus of claim 13, wherein the panel is slidably engageable on the major surface facing the water source.

15. The distillation electrolysis apparatus of claim 13, wherein the panel is slidably engageable on the major surface facing away from the water source.

16. A distillation electrolysis apparatus according to any one of claims 1 to 15, wherein the cell is operable as an alkaline water electrolyser.

17. A distillation electrolysis apparatus according to any one of claims 1 to 15, wherein the membrane comprises a proton exchange membrane, and wherein the cell is operable as a proton exchange membrane water electrolyser.

18. A distillation electrolysis apparatus according to any one of claims 1 to 15, wherein the membrane comprises an anion exchange membrane, and wherein the cell is operable as an anion exchange membrane water electrolyser.

19. A distillation electrolysis device according to any one of claims 1 to 18, wherein during operation and in response to current supplied to the cathode and the anode, water contacting the cathode and the anode is electrochemically decomposed to generate hydrogen at the cathode and oxygen at the anode, and wherein the hydrogen is separated from the oxygen by the diaphragm.

20. A distillation electrolysis device for use with a water source, the distillation electrolysis device comprising: A plurality of pools, each pool of the plurality of pools comprising: a first electrode; a second electrode, the first electrode and the second electrode forming an operational, paired anode and cathode; and a diaphragm disposed between the first electrode and the second electrode to define a first chamber and a second chamber, the first electrode being disposed in the first chamber, and the second electrode being disposed in the second chamber, the first chamber and the second chamber being in fluid communication with each other only through the diaphragm; a membrane, the plurality of cells being in fluid communication with the water source only through the membrane; and A baffle, wherein the baffle comprises an imperforate panel movable relative to a major surface of the membrane to expose a variable region of the membrane to the water source.

21. The distillation electrolysis apparatus of claim 20, wherein water transport from the water source through the membrane toward the plurality of cells is at least partially achieved by a vapor pressure differential across the membrane.

22. The distillation electrolysis apparatus of claim 20, wherein water transport from the water source through the membrane toward the plurality of cells is at least partially achieved by an osmotic pressure differential across the membrane.

23. The distillation electrolysis device according to claim 20, wherein the membrane comprises a hydrophilic membrane element, and the hydrophilic membrane element is configured to achieve liquid phase transmission of liquid water from the water source toward the plurality of tanks in response to an osmotic pressure difference across the membrane.

24. The distillation electrolysis device according to claim 20, wherein the membrane comprises a hydrophobic membrane element, and the hydrophobic membrane element is configured to achieve gas phase transport of water vapor from the water source toward the plurality of cells in response to a vapor pressure difference across the membrane.

25. The distillation electrolysis device according to any one of claims 20 to 24, wherein the paired anode and cathode of any one of the plurality of cells are connected in parallel with the paired anode and cathode of another of the plurality of cells.

26. The distillation electrolysis device according to any one of claims 20 to 24, wherein the paired anode and cathode of any one of the plurality of cells are connected in series with the paired anode and cathode of another of the plurality of cells.

27. A distillation electrolysis device according to any one of claims 20 to 26, wherein the membrane forms part of a wall of at least one of the plurality of cells, the wall being part of one or both of the first chamber and the second chamber, and wherein the membrane is involved in each of one or more transport paths from the water source toward the plurality of cells.

28. The distillation electrolysis device according to any one of claims 20 to 26, further comprising an electrolyte storage tank, which is disposed outside the plurality of cells and is connected to the water source fluid only through the membrane, wherein the membrane is disposed outside the plurality of cells and is interposed in each of one or more transmission paths from the source toward the plurality of cells.

29. A method comprising: A stock solution is provided to a cell, the cell comprising: a first electrode; a second electrode, the first electrode and the second electrode forming an operational, paired anode and cathode; and a diaphragm disposed between the first electrode and the second electrode to define a first chamber and a second chamber, the first electrode being disposed in the first chamber, and the second electrode being disposed in the second chamber, the first chamber and the second chamber being in fluid communication with each other only through the diaphragm; controlling a variable area of ​​the membrane exposed to a water source by moving an imperforate face plate of a baffle relative to a major surface of the membrane; wherein the stock solution is in fluid communication with the water source only through the membrane.

30. The method of claim 29, wherein the stock solution is formed by transporting water from the water source through the membrane toward the pool, and wherein the transport comprises any one of: (i) liquid phase transport of liquid water through the membrane in response to an osmotic pressure difference across a hydrophilic membrane element, and (ii) vapor phase transport of water vapor in response to a vapor pressure difference across a hydrophobic membrane element.

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