Electrical systems for generating hydrogen gas and methods for the use thereof

Abstract

The present disclosure related to an electrochemical system and a method of generation of hydrogen gas, wherein the electrochemical system comprises a modular anode that includes a carbon containing material having a high capacitance and specific surface area. Benefits of the electrochemical systems and methods disclosed herein can include electrochemical generation of hydrogen gas with reduced energy consumption, elimination of oxygen production, and deionization or dechlorination of water.

Description

Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCTELECTRICAL SYSTEMS FOR GENERATING HYDROGEN GAS AND METHODS FOR THE USE THEREOFCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This Application claims priority to U.S. Provisional 63 / 667,035, filed on July 2, 2024, the entirety of which is incorporated by reference.TECHNICAL FIELD

[0002] The present disclosure generally relates to the fields of electrochemistry, hydrogen gas generation, water reclamation, and green technology. In particular, the present disclosure provides highly scalable electrochemical systems for generating hydrogen gas from water and methods for using the same. In some embodiments, present disclosure also provides the ability to generate hydrogen gas while dechlorinating water.BACKGROUND

[0003] As the earth’s population grows, modem technology struggles to find a way to accommodate two seemingly impossible dreams: providing enough power for an ever-expanding population while providing clean energy to reduce or reverse global warming. Hydrogen gas seems to hold the key to providing clean power because hydrogen gas can be combusted or used in fuel cells to provide clean energy with water as the only product. However, hydrogen gas technology suffers from many challenges, including that providing clean hydrogen gas often consumes more power than it provides. Also, the high cost of providing clean hydrogen gas often makes hydrogen gas production unscalable and unprofitable. But what if there was a scalable way to generate hydrogen gas with low power consumption? What if there was a way to produce pure hydrogen gas while reclaiming undrinkable water?

[0004] One of the conventional methods for producing hydrogen gas is through an electrochemical process. In a typical electrochemical process, cathodes are the sites where hydrogen ions are reduced to form hydrogen gas as shown in the chemical reaction below:2H++ 2e'— >H2(g)Similarly, in a standard electrolyzer, water is oxidized to oxygen gas at the anode electrode as shown in the chemical reaction below:2H2O — >4H++ O2(g)+4e-Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCTThe overall balanced reaction of the electrolysis of water to form hydrogen and oxygen is schematically represented below:2H2O — >2H2(g)+ O2(g)

[0005] Therefore, the conventional electrochemical production of hydrogen gas, water is consumed, and oxygen gas is produced as a byproduct that must be removed from the product gases to obtain pure hydrogen gas.

[0006] There is a need for electrochemical systems and methods of generation of hydrogen gas that are scalable and reduce power consumption. There is a need for electrochemical systems and methods of generation of hydrogen gas that avoid or reduce the requirement of separating oxygen gas from the hydrogen gas produced. There is a need for electrochemical systems and methods of generation of hydrogen gas that can be made more efficient in terms of lower operating costs and using water sources other than clean or highly refined water.SUMMARY

[0007] The present disclosure provides electrochemical systems. In some embodiments, the electrochemical system comprises an electrical device, wherein the electrical device includes a modular anode electrically connected to a cathode and a power source, wherein the modular anode and the cathode are in contact with a hydrogen generation solution or a regeneration solution, wherein the modular anode includes a carbon containing material bound to a conductive support, wherein the carbon containing material has a specific surface area of from about 250 m2 / g to about 3,000 m2 / g.

[0008] In some embodiments, the carbon containing material includes carbon nanotubes, fullerenes, graphene, an activated carbon material, or a combination thereof. In some embodiments, from about 80% to about 100% of a weight of the carbon containing material includes carbon nanotubes, fullerenes, graphene, an activated carbon material, or a combination thereof, based on a total weight of the carbon containing material. In some embodiments, the carbon containing material includes a carbon containing panel bound to the conductive support by a conductive adhesive. In some embodiments, the carbon containing material has a specific capacitance measuring from about 10 F / g to about 80 F / g when measured by cyclic voltammetry. In some embodiments, the carbon containing material has a specific capacitance measuring from about 50 F / g to about 60 F / g when measured by cyclic voltammetry. In some embodiments, the carbon containing material has a specific surface area of from about 250 m2 / g to about 2,500 m2 / g. In some embodiments, the carbon containing material has a specific surface area of from about 250 m2 / g to about 2,000 m2 / g. In some embodiments, the carbon containing material has aChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT specific surface area of from about 500m2 / g to about 2,500 m2 / g. In some embodiments, the carbon containing material has a specific surface area of from about 500 m2 / g to about 2,000 m2 / g. In some embodiments, the carbon containing material includes a carbon containing panel bound to the conductive support by a conductive adhesive. In some embodiments, the modular anode includes from 1 to 100 modular anodes, and from about 30% to about 100% of the modular anodes based on a total amount of modular anodes, include the carbon containing panel. In some embodiments, the carbon containing panel has a panel longest dimension of from about 10.0 cm to about 20.0 cm and a panel shortest dimension of from about 0.64 cm to about 1.27 cm. In some embodiments, the carbon containing panel has a rectangular shape, having a panel height, panel width, or combination thereof of from about 10.0 cm to about 20.0 cm, and a panel thickness of from about 0.64 cm to about 1.27 cm. In some embodiments, the carbon containing panel has a panel longest dimension of from about 305.0 cm to about 3,050.0 cm and a panel shortest dimension of from about 19.0 cm to about 190.0 cm. In some embodiments, the carbon containing panel has a rectangular shape having a panel height, a panel width, or combination thereof of from about 305.0 cm to about 3,050.0 cm and a panel thickness of from about 19.0 cm to about 190.0 cm. In some embodiments, the cathode includes a platinum alloy. In some embodiments, the conductive support includes titanium, aluminum, nickel, a stainless steel, an iron-chrome alloy, or alloys thereof. In some embodiments, the conductive adhesive includes conductive particles suspended in an epoxy. In some embodiments, the conductive particles include a metal particle, a carbon particle, or a combination or mixture thereof. In some embodiments, the electrochemical system includes a liquid container that contains the hydrogen generation solution or the regeneration solution without a solid barrier, a gel barrier, or a membrane barrier located between the modular anode and the cathode. In some embodiments, the hydrogen generation solution includes water, or water and NaCl. In some embodiments, the hydrogen generation solution includes water and Cl'. In some embodiments, the regeneration solution includes water and FeSCh, Fe2(SO4)3, SnSCh, SnSCh, AsCh'3, As2(SO4)s, SeCh, SeCh, or combinations or mixtures thereof. In some embodiments, the regeneration solution includes water and Fe+2, Fe+3, Sn+2, Sn+3, Se+2, Se+3, or combinations or mixtures thereof.

[0009] The present disclosure further provides methods of generating hydrogen gas. In some embodiments, the method of generating hydrogen gas comprises: providing an electrochemical system that includes an electrical device, wherein the electrical device includes a modular anode electrically connected to a cathode and a power source, wherein the modular anode and the cathode are in contact with a hydrogen generation solution or a regeneration solution, wherein the modular anode includes a carbon containing material bound to a conductive support, whereinChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT the carbon containing material has a specific surface area of from about 250 m2 / g to about 3,000 m2 / g; generating the hydrogen gas at the cathode by contacting the modular anode and the cathode with a hydrogen generation solution and applying a constant DC potential of about 0.5 V to about 3.0 V across the modular anode and the cathode until the measured current between the modular anode and the cathode increases to a hydrogen generation peak current and then passes from the hydrogen generation peak current to a constant current threshold; and regenerating a capacitance of the carbon containing material by: reducing a DC potential between the anode and cathode to 0.0 V and by reacting the carbon containing material with a regeneration solution, or reducing a capacitance of the carbon containing material by reacting the modular anode with a regeneration solution.

[0010] In some embodiments, the method includes: before regenerating a capacitance of the carbon containing material or before reducing a capacitance of the carbon containing material, providing a regeneration solution by adding a reducing agent to an aqueous solution, wherein the aqueous solution is the hydrogen generation solution or a pre-regeneration aqueous solution. In some embodiments, the reducing agent is FeSCh, SnSCh, As, SeCh, Fe+2, Sn+2, Se+2, or combinations or mixtures thereof. In some embodiments, the method comprises: forming Fe+3, Sn+3, As+2, Se+3, or a combination or mixture thereof, by reacting the reducing agent with the modular anode. In some embodiments, the constant DC potential varies by from 0.0 to about 0.2 V while hydrogen is generated at the cathode. In some embodiments, the hydrogen generation peak current is from about 1.0 A to about 150.0 A, or more. In some embodiments, the constant current threshold is from 0.0 to about 20.0 A, and varies by from about 0.1% to about 5% based on the measured current. In some embodiments, reducing the DC potential between the anode and cathode to 0.0 V includes disconnecting the DC voltage supply from the modular anode, the cathode, or a combination thereof. In some embodiments, the method comprises forming a dechlorinated solution from the hydrogen generation solution by sequestering Cl’ onto or near the modular anode while applying the DC voltage of about 0.5 V to about 3.0 V across the modular anode and the cathode. In some embodiments, a 1 L sample of the dechlorinated solution has a lower CF concentration than a 1 L sample of the hydrogeneration solution. In some embodiments, the dechlorinated solution Cl’ concentration is from about 10% to about 99% lower than a hydrogen generation solution Cl’ concentration. In some embodiments, the method includes, before regenerating a capacitance of the carbon containing material or before reducing a capacitance of the carbon containing material, removing the hydrogen generation solution or the dechlorinated solution from the electrochemical system, or separating the dechlorinated solution from the hydrogen generation solution or the regeneration solution. InChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT some embodiments, the method comprises harvesting the hydrogen gas from the electrochemical system, or harvesting the hydrogen gas from the electrochemical system at a rate of about 1 kg / day to about 20 kg / day per cell.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The foregoing summary, as well as the following detailed description of the embodiments, will be better understood when read in conjunction with the attached drawings. For the purpose of illustration, there are shown in the drawings some embodiments, which may be preferable. It should be understood that the embodiments depicted are not limited to the precise details shown. Unless otherwise noted, the drawings are not to scale.

[0012] FIG. 1 illustrates a schematic depiction of an embodiment of a modular anode.

[0013] FIG. 2 illustrates an embodiment of a step of generation hydrogen gas at the cathode.

[0014] FIG. 3 illustrates an embodiment of a step of regenerating capacitance of the modular anode by reducing the charge build up on the anode.

[0015] FIG. 4 shows an embodiment of the current vs. time response for a complete cycle comprising embodiments of steps of hydrogen gas generation, regeneration of capacitance of a modular anode, and again hydrogen gas generation.

[0016] FIG. 5 illustrates a schematic depiction of an embodiment of an electrochemical device comprising multiple electrode pairs during an embodiment of a large-scale hydrogen gas generation step.

[0017] FIG. 6 illustrates a schematic depiction of an embodiment of an electrochemical device comprising multiple electrode pairs during an embodiment of a large-scale capacitance regeneration step.DETAILED DESCRIPTION

[0018] Unless otherwise noted, all measurements are in standard metric units.

[0019] Unless otherwise noted, all instances of the words “a,” “an,” or “the” can refer to one or more than one of the word that they modify.

[0020] Unless otherwise noted, the term “about” refers to ±10% of the non-percentage number that is described, rounded to the nearest number to the accuracy shown. For example, about 105.3 mm, would include 94.8 to 115.8 mm. Unless otherwise noted, the term “about” refers to ±5% of a percentage number. For example, about 20% would include 15 to 25%. When the term “about” is discussed in terms of a range, then the term refers to the appropriate amountChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT less than the lower limit and more than the upper limit. For example, from about 100 to about 200 mm would include from 90 to 220 mm.

[0021] Unless otherwise noted, a range of numbers includes all numbers in that range. For example, the range of 250 m2 / g to about 3,000 m2 / g includes 280, 300, 400, 500, 600, 100, 1200, 1500, 2000, 2200, 2500 and any sub-range therein.

[0022] The term “for example” or “e.g.,” as used herein, is used merely by way of example, without limitation intended, and should not be construed as referring only those items explicitly enumerated in the specification.

[0023] The term “constant current threshold” refers to a measurable current that is from 0 to 20% greater than a minimum current measurable for a given solution and a constant voltage. In embodiments of the electrochemical system as disclosed herein, when a constant potential is applied across a solution, the capacitance builds up on the anode, the reaction will slow, and the current will drop until it reaches a measurable current minimum. This measurable current minimum is inherent to the combination of the composition of the solution, the electrodes, and constant potential applied. The constant current threshold is a current based on the “minimum measurable current” that is selected by the operator for at or below which the system will be switched from a hydrogen generation mode to a capacitance regeneration mode. So, the constant current threshold can be set at a current higher than minimum measurable current for the sake of efficiency, but the lower limit or measurable current minimum will depend on a variety of factors, including the potential used and the properties and composition of the solution.

[0024] Unless otherwise noted, the “measurable current minimum” refers to the lowest measurable current that a given embodiment of an electrochemical system and given hydrogen generation solution can obtain at a constant applied potential. The “measurable current minimum” can be determined by applying a constant voltage three times to a given solution in a given electrochemical system until the current varies by from 0.1% to about 5% based on the measured current, and then averaging the lowest current measured for that solution to provide the measurable current minimum. The constant current threshold and the measurable current minimum can be the same or different.

[0025] Unless otherwise noted, the “hydrogen generation solution” refers to an aqueous solution or volume of liquid that includes at least 90% water by weight based on a total weight of hydrogen generation solution.

[0026] Unless otherwise noted, the “regeneration solution” refers to refers to an aqueous solution or volume of liquid that includes at least 90% water by weight based on a total weight of regeneration solution and includes a concentration of at least 100.0 ppm reducing agent.Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCT

[0027] Unless otherwise noted, the “regeneration solution” refers to an aqueous solution or volume of liquid that includes at least 90% water by weight based on a total weight of regeneration solution and does not include a concentration of at least 100.0 ppm reducing agent.

[0028] Unless otherwise noted, the terms “provide”, “provided” or “providing” refer to the supply, production, purchase, manufacture, assembly, formation, selection, configuration, conversion, introduction, addition, or incorporation of any element, amount, component, reagent, quantity, measurement, or analysis of any method or system of any embodiment herein.

[0029] Unless otherwise noted, properties (height, width, length, ratio etc.) as described herein are understood to be averaged measurements.

[0030] There are many conventional electrochemical processes for generating hydrogen gas, but these conventional processes suffer from one or more disadvantages. For example, conventional methods produce hydrogen gas that is mixed with oxygen gas (contaminant), requiring the large-scale separation of oxygen gas (purification) from hydrogen gas before use. This requirement tremendously raises the cost and lowers the efficiency of the hydrogen generation process because oxygen gas is usually separated from hydrogen gas by such inefficient and costly techniques as pressure swing adsorption, cryogenic distillation, or selectively permeable membranes. Also, processing and storing oxygen gas increases safety costs of conventional hydrogen generation processes because oxygen is a highly oxidizing gas, especially with hydrogen. Thus, these conventional processes require the handling of the flammable hydrogen gas that is desired, and the oxidizing oxygen gas that is not desired.

[0031] Further, conventional electrochemical processes for generating hydrogen gas typically require highly processed water that is either purified or purified and then has salt added. This requirement is necessary because pure water is highly non-conductive, and hence, exhibits high ohmic resistance. For example, in the conventional process, where pure water is used, a minimum potential of about 2V DC is needed. With a current rate of 10,000 amps, Faraday’s law (at 100% current efficiency) predicts the production of about 8,700 g (~9 kg) of hydrogen gas per day. For a minimum voltage of 2V DC, about 20,000 W of power would be consumed to produce about 9 kg of hydrogen gas per day. Such a conventional process would require about 480,000 Whr of energy to be consumed to produce about 9 kg of hydrogen gas. Simply put, the conventional electrochemical cell consumes about 53.6 kWh of electrical energy per kg of hydrogen gas production. This cost is significantly higher than the energy recovered in combusting hydrogen gas.

[0032] To overcome the problem of non-conductivity of pure water, and to reduce the power consumption for hydrogen gas production, salts (such as chloride salts) are added to theChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT electrochemical cells. However, addition of these salts contaminates (poisons) the reaction mixture by formation of additional by-products such as chlorine gas at the anode electrode. Also, the addition of these chloride salts increase costs and decrease efficiency when trying to increase the scale of the process, because these conventional processes would create large volumes of wastewater, namely, a brine that is useless for drinking or irrigation of land.

[0033] The electrochemical systems, and methods for the using the same, presented herein provide a solution to the above-mentioned problems by providing a new and improved modular anode electrode including a carbon-containing material that allows for the production of hydrogen gas, which is free of oxygen, while dramatically reducing the overall consumption of power or energy needed for the production of the hydrogen gas. Embodiments of the electrochemical systems, and methods for the using the same, disclosed herein are based on the premise, at least in part, of precluding or eliminating part of the conventional electrochemical reactions, i.e., oxygen generation at anode, by replacing the conventional anode with a modular anode having a high surface area and a high capacitance. For example, such a modular anode can be as simple as a carbon containing material bound to a conductive support. This elimination of the production of oxygen gas increases the efficiency and lowers the cost of the hydrogen generation processes disclosed herein.

[0034] Further, as would be those familiar with electrochemistry, the portion of the conventional chemical reaction at the anode amounts to the larger of the two half-cell potentials, amounting to about 60% of the voltage. Thus, eliminating the reaction of this half-cell (by replacing the conventional anode with a capacitive anode) can dramatically reduce the overall energy consumption required for producing the hydrogen gas by about 40% to about 60% while eliminating the generation of oxygen and hence, precluding the need for purification of the hydrogen gas.

[0035] Without wishing to be bound by the theory, it is believed that the capacitive anode serves as a storage device for electrical charge, which counters the electrical charge consumed or generated in the cathode connected through the electrolyte. The capacitive anode eliminates the need for a chemical reaction at the anode, which allows the current to continue from the chemically active cathode to the capacitive anode (and vice versa). As DC-current is applied to the cell, ions (such as CF ions present in the electrolyte) continue to be attracted to the charged anode until the anode reaches its maximum capacitance, wherein 4 H+are removed from the electrolyte to form hydrogen gas at the cathode and 4 CF are adsorbed or sequestered onto or near the surface of the anode resulting in a net “no change” in the ratio of negative and positiveChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT charge in the bulk solution. In this way, the capacitive anode continues to operate as it accumulates charge until it stores its maximum capacitance.

[0036] It should be appreciated that replacement of a conventional anode in a conventional electrochemical cell with an anode having large capacitance affords continuous production of hydrogen gas at the cathode for a long enough time to be industrially useful. It has been discovered that the usage of a carbon containing material, such as carbon nanotubes, fullerenes, graphene, an activated carbon material, or a combination thereof, having a large surface area offers this significantly high capacitance and hence, an electrochemical system having a modular anode made of the carbon containing material affords continuous production of hydrogen gas at the cathode for a long enough time to be industrially useful.

[0037] Next, balance must be restored to the system to continue operation. Once the capacitive anode reaches its maximum capacitance, the stored charge must be dissipated to regenerate the capacitance of the anode. The stored charge can be dissipated by shorting the cathode with the anode, but this can lead to the production of oxygen as the charge is dissipated. Instead, the stored charge can be dissipated, for example, by consuming the stored energy for effecting oxidation reactions such as converting (oxidizing) ferrous (Fe+2) ions to ferric (Fe+3) ions. Once the capacitance of the anode is regenerated, the cell is again ready for generation of hydrogen gas.

[0038] It has been further discovered that this sequestration of chloride ions could be used to dechlorinate water by moving water through the disclosed electrochemical system. For example, a hydrogen generation solution can be flowed into contact with the carbon containing material during hydrogen generation, which will cause negative ions, such as a chloride ion of sodium chloride to be adsorbed or sequestered onto or near the surface of the carbon containing material, concentrating and effectively removing the chloride ions from the hydrogen generation solution. Then, during the regeneration step, the charge is removed from the carbon containing material surface as reducing agents donate electrons to the modular anode, which causes the negative ions, such as chloride ions to desorb or release from the surface of the carbon containing material. As this process is repeated, this process can effectively dechlorinate or reduce the chlorine content of water used in the hydrogen generation solution by concentrating the chlorine ions it into the regeneration solution. This dechlorination process could result in the water exiting the electrochemical system having a higher pH due to the generation of OH' ions and higher sodium ions, due to the buildup of left over sodium ions. However, the water can be further processed to make it acceptable by, for example, adding citric acid, which is natural and would lower the pH and produce sodium citrate, which is harmless.Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCT

[0039] The regeneration process would produce high concentrations of oxidized ions in the regeneration solution, such as an abundance of Fe+3from FeSCh. However, Fe+3containing solutions can also be recycled by, for example, running the solutions over iron containing materials to remove the iron and replenish the Fe SO4 containing regeneration solution.

[0040] In summary, an electrochemical system, and methods of using the same, have been discovered that can generate hydrogen gas without generation oxygen, using greatly reduced amounts of power, and is scalable. Further, the electrochemical system, and methods of using the same, can also be used to dechlorinate large volumes of water being used as a hydrogen generation solution by concentrating the chloride ions as high chloride content regeneration solutions for further processing.

[0041] FIG. 1 illustrates a schematic depiction of an embodiment of a modular anode 100. As shown in FIG. 1, this embodiment of the modular anode 100 comprises a carbon containing material bound to a conductive support 102, wherein the carbon containing material includes a carbon containing panel 106 bound to the conductive support 102 by a conductive adhesive 104.

[0042] In some embodiments of the method of generation hydrogen gas disclosed herein, the method includes two steps or stages: (i) step 1 is generation of hydrogen gas, and (ii) step 2 is regeneration of capacitance of the anode (carbon containing material) or modular anode. These two steps can be repeated as necessary.

[0043] FIG. 2 depicts an embodiment of a step 200 of generation of hydrogen gas at the cathode in the electrochemical system of the present disclosure. As shown in FIG. 2, hydrogen gas is generated at the cathode 210 by contacting the modular anode 208 and the cathode 210 with a hydrogen generation solution 212 and applying a DC potential (by connecting and applying a DC power supply 214) of about 0.5 V to about 3.0 V across the modular anode 208 and the cathode 210 until the measured current between the modular anode 208 and the cathode 210 increases to a hydrogen generation peak current, and then passes from the hydrogen generation peak current to a constant current threshold. In this embodiment of the electrochemical system, the modular anode 208 comprises a carbon containing material bound to a conductive support 202, wherein the carbon containing material includes a carbon containing panel 206 bound to the conductive support 202 by a conductive adhesive 204. In this embodiment of the method, the hydrogen gas is generated at the cathode 210 along with hydroxide ions while CF are adsorbed or sequestered onto or near the surface of the carbon- containing material anode. Therefore, hydrogen gas is generated without generating oxygen gas, while absorbing CF from the hydrogen generation solution 212 onto or near the modular anode 208. As the capacitance of the modular anode 208 increases, the hydrogen gas generation tendsChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT to slow down because the voltage can no longer drive the electrochemical reaction. Once maximum capacitance of the modular anode 208 is reached hydrogen production stops, or is reduced, requiring regeneration of the capacitance of the modular anode 208.

[0044] FIG. 3 depicts an embodiment of the step 300 of regeneration of capacitance of the modular anode in the electrochemical system of the present disclosure. The capacitance of the modular anode can be reduced (regenerated) by either reducing a DC potential between the modular anode 308 and cathode 310 to 0.0 V or by disconnecting the DC power before, during, or after reacting the carbon containing material with a regeneration solution. That is the capacitance of the carbon containing material is reduced by reacting the modular anode 308 with a regeneration solution 312. As shown in FIG. 3, in accordance with an embodiment of the electrochemical system, a cathode 310 and a modular anode 308 are in contact with each other through a regeneration solution 312. In this step, hydrogen generation solution 212 is replaced with a regeneration solution 312. This replacement step can be performed by adding a reducing agent to an aqueous solution (a hydrogen generation solution 212 or a pre-regeneration aqueous solution). Alternatively, the hydrogen generation solution 212 can be drained to obtain dechlorinated water, and the volume can be filled with a fresh water that can be converted into a regeneration solution 312 by adding the reducing agent selected from FeSCh, SnSCh, As, SeCh, Fe+2, Sn+2, Se+2, or combinations or mixtures thereof. In the regeneration step 300, ions such as Fe+3, Sn+3, As+2, Se+3, or a combination or mixture thereof transfer an electron onto the modular anode 308, which reduces the charge stored on the modular anode 308. This step lowers the charge of the modular anode 308 such that the hydrogen gas generation step can be repeated, allowing generation of large volumes of hydrogen gas and dechlorinated water by alternate repetition of the steps of hydrogen gas generation and regeneration of capacitance of the modular anode 308.

[0045] FIG. 4 depicts current vs. time response 400 for a complete cycle comprising the steps of hydrogen gas generation 402, regeneration of capacitance of the modular anode 404, and hydrogen gas generation 406 again. In this embodiment of the method, as shown in FIG. 4, upon applying a DC potential (by using DC power supply), for example, of about 0.5 V to about 3.0 V across the modular anode and the cathode, the measured current between the modular anode and the cathode increases to a hydrogen generation peak current 408, and then passes from the hydrogen generation peak current through a constant current threshold 410 to a minimum measurable threshold 412. Once the constant current threshold and / or minimum measurable threshold is reached (in this embodiment constant current threshold and minimum measurable are different), the DC power can be reduced by turning off or even disconnecting the powerChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT supply. This disconnection step starts regeneration of the capacitance of the modular anode while the that the regeneration solution is in contact with the anode as shown in FIG. 4. Once the capacitance of the modular anode is regenerated, the step of hydrogen generation can be repeated by applying a DC potential.

[0046] In some embodiments, the electrochemical system and methods for using the system are configured for continuous operation to promote scalability, lower costs, and make the embodiment economically feasible. FIG. 5 illustrates a schematic depiction of an embodiment of the electrochemical system 500 during an embodiment of the hydrogen generation step comprising multiple electrode pairs for hydrogen gas generation. As shown in FIG. 5, the system 500 houses multiple pairs of modular anodes 502 and multiple pairs of cathodes 506 arranged in an alternate fashion, with an inlet 512 and an outlet 514 located at opposite ends of the device 500. As can also be seen from FIG. 5, in accordance with an embodiment, the pairs of modular anodes 502 and the pairs of cathodes 506 define a winding path 520 to increase the surface area for the reaction and to ensure maximum adsorption or sequestration of chloride ions from the hydrogen generation solution 510 that flows through the winding path. In this embodiment, one or more cathode busbar 508 and one or more anode busbar 504 can be included in the device 500 for supporting and electrically connecting cathodes 506 and modular anodes 502, respectively. For hydrogen generation, the hydrogen generation solution 510 is input in the device 500 through the inlet 512, and DC current 518 is supplied to the modular anodes 502 and cathodes 506 through the respective busbars 504, 508. When DC-current (power supply 518) is applied, negative ions (such as CF ions present in the hydrogen generation solution) continue to be attracted to the modular anodes 502 until the modular anodes 502 reach their maximum capacitance, wherein 4 H+are removed from the hydrogen generation solution 510 to form hydrogen gas at the cathodes 506 and 4 CF are adsorbed or sequestered onto or near the surface of the modular anodes 502. For continuous production of hydrogen gas and adsorption or sequestration of CF, hydrogen generation solution 510 can be continuously flowed through the system 500 into the inlet 512 while the dechlorinated hydrogen generation solution 511 can be continuously removed from the system 500 via outlet 514. In an embodiment, the present disclosure provides a cost-effective method for producing the hydrogen gas along with a large amount of dechlorinated water while eliminating the generation of oxygen and hence, precluding the need for purification of the hydrogen gas. This affords another advantage that - alongside the production of the hydrogen gas, waste water or water that is unsuitable for drinking can be reclaimed owing to deionization (such as dechlorination) of the water.Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCT

[0047] FIG. 6 illustrates a schematic depiction of an embodiment of an electrochemical device 600 during an embodiment of a step of regenerating capacitance of the modular anode using the same system as shown in FIG. 5. As shown in FIG. 6, an embodiment of the electrochemical system 600 houses multiple pairs of modular anodes 602 and multiple pairs of cathodes 606 arranged in an alternate fashion, with an inlet 612 and an outlet 614 defined on the device 600. As can also be seen from FIG. 6, in accordance with the embodiment, the pairs of modular anodes 602 and the pairs of cathodes 606 defines a winding path 620. In this embodiment, the one or more cathode busbar 608 and one or more anode busbar 604 are still supporting and electrically connecting cathodes 606 and modular anodes 602, respectively. For regenerating the capacitance of the modular anodes 602, the regeneration solution 610 is input in or flowed into the device 600 through the inlet 612. During regeneration of capacitance of the modular anodes 602, no current is supplied from power source 618. When the regeneration solution 610 is passed through multiple pairs of modular anodes 602 and multiple pairs of cathodes 606 arranged in an alternate fashion, the charge stored in the modular anodes 602 is reduced by an oxidation reaction with the regeneration solution 610, such as for converting ferrous (Fe+2) ions to ferric (Fe+3) ions. During the regeneration of capacitance of the modular anodes 602 step, the CF ions adsorbed or sequestered onto or near the surface of the modular anodes 602 are desorbed or pass into the regeneration solution 610 forming a solution 611 rich in chloride ions (and ferric (Fe+3) ions). The solution 611 can be removed from the device 600 through the outlet 614. Once the capacitance of the modular anodes 602 is regenerated, the device is again ready for hydrogen gas generation.

[0048] The present disclosure provides electrochemical systems. In some embodiments, the electrochemical system comprises an electrical device, wherein the electrical device includes a modular anode electrically connected to a cathode and a power source. In some embodiments, the modular anode and the cathode are in contact with a hydrogen generation solution or a regeneration solution. In some embodiments, the modular anode includes a carbon containing material bound to a conductive support. In some embodiments, the carbon containing material has a specific surface area of from about 250 m2 / g to about 3,000 m2 / g.

[0049] In some embodiments, the carbon containing material includes carbon nanotubes, fullerenes, graphene, an activated carbon material, or a combination thereof. In some embodiments, from about 80% to about 100% of a weight of the carbon containing material includes carbon nanotubes, fullerenes, graphene, an activated carbon material, or a combination thereof, based on a total weight of the carbon containing material. In some embodiments, from about 82% to 98% of a weight of the carbon containing material includes carbon nanotubes,Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCT fullerenes, graphene, an activated carbon material, or a combination thereof, based on a total weight of the carbon containing material, including sub-ranges such as from about 84% to 95% weight or from about 85% to 95% weight or from about 88% to 92% weight.

[0050] In some embodiments, the carbon containing material includes a carbon containing panel bound to the conductive support by a conductive adhesive. In some embodiments, the carbon containing material has a specific capacitance measuring from about 10 F / g to about 80 F / g when measured by cyclic voltammetry. In some embodiments, the carbon containing material has a specific capacitance measuring from about 50 F / g to about 60 F / g when measured by cyclic voltammetry. In some embodiments, the carbon containing material has a specific capacitance measuring from about 15 F / g to about 80 F / g when measured by cyclic voltammetry, including sub-ranges such as from about 20 F / g to about 75 F / g or from about 25 F / g to about 70 F / g or from about 30 F / g to about 70 F / g or from about 35 F / g to about 75 F / g or from about 40 F / g to about 70 F / g or from about 45 F / g to about 65 F / g.

[0051] In some embodiments, the carbon containing material has a specific surface area of from about 250 m2 / g to about 2,500 m2 / g. In some embodiments, the carbon containing material has a specific surface area of from about 250 m2 / g to about 2,000 m2 / g. In some embodiments, the carbon containing material has a specific surface area of from about 500 m2 / g to about 2,500 m2 / g. In some embodiments, the carbon containing material has a specific surface area of from about 500 m2 / g to about 2,000 m2 / g. In some embodiments, the carbon containing material has a specific surface area of from about 250 m2 / g to about 2,500 m2 / g, including sub-ranges such as from about 300 m2 / g to about 2,400 m2 / g or from about 350 m2 / g to about 2,400 m2 / g, from about 400 m2 / g to about 2,300 m2 / g, or from about 450 m2 / g to about 2,200 m2 / g, or from about 450 m2 / g to about 2,100 m2 / g, or from about 500 m2 / g to about 2,100 m2 / g.

[0052] Carbon containing material to form modular anode is detailed, for example, in U.S. Patent No. 6,350,520, contents whereof are incorporated herein, in its entirety, by way of reference. In some embodiments, the carbon containing material is produced by the application of heat and pressure for a prescribed time onto an amorphous carbon. In some embodiments, the carbon containing material is still amorphous and has superior properties over conventionally available carbon materials. In some embodiments, the properties of the carbon containing material are altered by choosing different source materials, by controlling the process parameters of the manufacturing process, or by blending specific materials prior to processing. In some embodiments, the properties of the carbon containing material are varied include, for example, densification, strength, porosity, conductivity and adsorptive surface area. By selecting materials and process parameters to achieve desired properties, carbon containing material is tailored forChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT their use in different electrochemical applications (i.e., water treatment, desalination, energy storage devices, etc.),

[0053] With respect to source material, preferably, the form of amorphous carbon that is used is powder activated carbon. The examples set forth herein utilize this form of amorphous carbon, however, it should be noted that the disclosure is not limited to the activated carbon form of amorphous carbon. One of the desirable characteristics of the carbon containing material that may be altered by using different amorphous carbon source material is the high adsorptive specific surface area. Carbon particles can be produced that have high specific surface areas (as measured by the BET isotherm or other analytical techniques) are selected to increase the net surface area of the carbon containing material after processing. Carbon source material is selected based upon surface area, hardness, density, and grain size.

[0054] Preferably, the device that carries out the elevated temperature compression of the amorphous carbon is a hot isostatic press (HIP) such as the MINI HIPer manufactured by ABB Autoclave Systems Inc (Ohio, USA). An advantage of using isostatic pressure is that the consolidation of the carbon is uniform throughout the material. However, it should be noted that other devices in addition to HIPs can be utilized for the consolidation under heat and pressure of the amorphous carbon.

[0055] With respect to the process parameters in the manufacture of the carbon containing materials, the process parameters of temperature, pressure and time are varied to alter the specific characteristics and properties of the produced carbon containing material. In some embodiments, the temperature ranges from about 200°C to about 2,700°C, the pressure ranges from about 500 (3447 kPa) to about 50,000 psi (344,737 kPa) and the holding time or time at temperature and pressure may vary from about 0.5 to about 20 hours. In some embodiments, the target pressure is obtained and the temperature is thereafter ramped up to the target value in a period of time such as one hour. It will be appreciated that all of these parameters interact and that can use a condition outside these cited ranges by compensating changes in other parameters.

[0056] The specific combination of parameters that is applied is determined for the specific material properties desired. For example, powder activated carbon consolidated at a temperature of about 800°C and a pressure of about 3 psi (20 kPa) for one hour is more porous and more brittle than carbon consolidated at a temperature of about 900°C and a pressure of about 25 psi (172 kPA) for one hour. The first carbon containing material is best used in an application such as an electrode, while the second carbon containing material is used as a structural material. Generally, changes to the process parameters of temperature, pressure and time directly effectChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT the properties of final density, strength, and porosity of the carbon containing material while the properties of conductivity, strength and adsorptive surface area are altered to lesser degree.

[0057] With respect to temperature in particular, the temperature ranges from about 600°C to about l,400°C. In some embodiments, temperatures for forming electrodes from carbon containing material are in the lower end of the range, from about 600°C to about l,000°C. In some embodiments, temperatures for forming structural products from carbon containing material are in the higher end of the temperature range, from about 800°C to about l,400°C.

[0058] With respect to pressure in particular, in some embodiments, the pressure ranges from about 500 psi (3,447 kPa) to about 25,000 psi (172,368 kPa). Pressures in the lower end of these ranges, for example, from about 500 psi (3,447 kPa) to about 20,000 psi (137,895 kPa) are typically preferred for making electrode material. Pressures in the higher end of the range, from about 2000 psi (13789 kPa) to about 25,000 psi (172,368 kPa) are typically preferred for making structural products. Pressure has an influence on the capacitance of any electrode made from carbon containing material. With higher pressures, more dense materials are produced, macropore size shifts and therefore a carbon containing material with a lower capacitance is obtained.

[0059] With respect to holding time, holding times of from about 0.75 hours to about 10 hours are typically preferred. Preferably, for electrode material, the holding times are shorter due to the desired surface area and porosity. It is generally beneficial to cool the carbon containing material products gradually after processing. Gradual cooling rates of from about 200° C / hr to about 1000°C / hr are typically, with ranges of about 300°C / hr to about 800°C / hr being most preferred.

[0060] Mixing fibers or other particles with the carbon source material prior to processing can dramatically increase the tensile and compressive strength of the carbon containing material. Long graphite fibers, for example, are blended to improve the directional strength. Short whiskers could be added to improve the strength isotropically. Depending on the processing parameters, the carbon particles in the source material will interact with any added carbon fibers in much the same way that they interact with each other, reducing the amount of pull-out or crack propagation. The weight proportion of added material in the final carbon containing material can range from 0% to about 40% and higher.

[0061] The focus and benefit of the numbers and dimensions of the modular anodes and their carbon containing materials or carbon containing panels is trying to balance the conflicting needs of scalability with those of cost-effective, high volume manufacturing.Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCT

[0062] In some embodiments, the carbon containing material includes a carbon containing panel bound to the conductive support by a conductive adhesive. In some embodiments, the modular anode includes from 1 to 100 modular anodes, including from 5 to 95 modular anodes or from 5 to 90 modular anodes or from 10 to 90 modular anodes or from 15 to 85 modular anodes or from 20 to 80 modular anodes, and from about 30% to about 100% of the modular anodes, including 35% to 99% of the modular anodes or 35% to 95% of the modular anodes or 40% to 90% of the modular anodes, based on a total amount of modular anodes, include the carbon containing panel.

[0063] In some embodiments, the carbon containing panel has a panel longest dimension of from about 10.0 cm to about 20.0 cm. In some embodiments, the carbon containing panel has a panel longest dimension of from about 11.0 cm to about 19.0 cm, including from about 12.0 cm to about 18.0 cm or from about 14.0 cm to about 17.0 cm. In some embodiments, the carbon containing panel has a panel shortest dimension of from about 0.64 cm to about 1.27 cm. In some embodiments, the carbon containing panel has a panel shortest dimension of from about 0.70 cm to about 1.20 cm, including from about 0.75 cm to about 1.15 cm or from about 0.80 cm to about 1.10 cm or from about 0.85 cm to about 1.05 cm or from about 0.90 cm to about 1.00 cm. In some embodiments, the carbon containing panel has a rectangular shape. In some embodiments, the carbon containing panel has a rectangular shape, having a panel height, panel width, or combination thereof of from about 10.0 cm to about 20.0 cm, and a panel thickness of from about 0.64 cm to about 1.27 cm.

[0064] In some embodiments, the carbon containing panel has a panel longest dimension of from about 305.0 cm to about 3,050.0 cm. In some embodiments, the carbon containing panel has a panel longest dimension of including from about 305.0 cm to about 3,050.0 cm including from about 350.0 cm to about 3,000.0 cm or from about 400.0 cm to about 2,900.0 cm or from about 450.0 cm to about 2800.0 cm or from about 500.0 cm to about 2,600.0 cm or from about 600.0 cm to about 2,500.0 cm or from about 750.0 cm to about 2,200.0 cm or from about 900.0 cm to about 2,000.0 cm. In some embodiments, the carbon containing panel has a panel shortest dimension of from about 19.0 cm to about 190.0 cm. In some embodiments, the carbon containing panel has a panel shortest dimension of from about 20.0 cm to about 180.0 cm, including from about 25.0 cm to about 170.0 cm or from about 30.0 cm to about 150.0 cm or from about 35.0 cm to about 140.0 cm or from about 40.0 cm to about 120.0 cm. In some embodiments, the carbon containing panel has a rectangular shape. In some embodiments, the carbon containing panel has a rectangular shape having a panel height, a panel width, orChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT combination thereof of from about 305.0 cm to about 3,050.0 cm and a panel thickness of from about 19.0 cm to about 190.0 cm.

[0065] In some embodiments, the cathode includes a platinum alloy. In some embodiments, the conductive support includes titanium, aluminum, nickel, a stainless steel, an iron-chrome alloy, or alloys thereof. In some embodiments, the conductive adhesive includes conductive particles suspended in an epoxy. In some embodiments, the conductive particles include a metal particle, a carbon particle, or a combination or mixture thereof. In some embodiments, the electrochemical system includes a liquid container that contains the hydrogen generation solution. In some embodiments, the electrochemical system includes a liquid container that contains the regeneration solution without a solid barrier, a gel barrier, or a membrane barrier located between the modular anode and the cathode.

[0066] In some embodiments, the hydrogen generation solution includes water, or water and NaCl. In some embodiments, the hydrogen generation solution includes water and Cl'. In some embodiments, the regeneration solution includes water and FeSCh, Fe2(SO4)3, SnSCh, SnSCh, As, AS2(SO4)S, SeCh, SeCh, or combinations or mixtures thereof. In some embodiments, the regeneration solution includes water and Fe+2, Fe+3, Sn+2, Sn+3, As, As+2, Se+2, Se+3, or combinations or mixtures thereof.

[0067] The present disclosure further provides a method of generating hydrogen gas. In some embodiments, the method of generating hydrogen gas comprises providing an electrochemical system that includes an electrical device. In some embodiments of the method, the electrical device includes a modular anode electrically connected to a cathode and a power source. In some embodiments of the method, the modular anode and the cathode are in contact with a hydrogen generation solution or a regeneration solution. In some embodiments of the method, the modular anode includes a carbon containing material bound to a conductive support. In some embodiments of the method, the carbon containing material has a specific surface area of from about 250 m2 / g to about 3,000 m2 / g. In some embodiments, the method includes generating the hydrogen gas at the cathode by contacting the modular anode and the cathode with a hydrogen generation solution and applying a constant DC potential of about 0.5 V to about 3.0 V across the modular anode and the cathode until the measured current between the modular anode and the cathode increases to a hydrogen generation peak current and then passes from the hydrogen generation peak current to a constant current threshold. In some embodiments, the method includes regenerating a capacitance of the carbon containing material by reducing a DC potential between the anode and cathode to 0.0 V and by reacting the carbon containing material with aChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT regeneration solution, or reducing a capacitance of the carbon containing material by reacting the modular anode with a regeneration solution.

[0068] In some embodiments, the method includes: before regenerating a capacitance of the carbon containing material or before reducing a capacitance of the carbon containing material, providing a regeneration solution by adding a reducing agent to an aqueous solution. In some embodiments, the aqueous solution is the hydrogen generation solution. In some embodiments, the aqueous solution is a pre-regeneration aqueous solution. In some embodiments, the reducing agent is FeSCh, SnSCh, As, SeCh, Fe+2, Sn+2, Se+2, or combinations or mixtures thereof.

[0069] In some embodiments, the method comprises forming Fe+3, Sn+3, As+2, Se+3, or a combination or mixture thereof, by reacting the reducing agent with the modular anode. In some embodiments, the constant DC potential varies by from 0.0 to about 0.2 V while hydrogen is generated from the cathode. In some embodiments, the hydrogen generation peak current is from about 1.0 A to about 150.0 A, or more. In some embodiments, the hydrogen generation peak current is from about 1.0 A to about 150.0 A, or more, including from about 4.0 A to about 140.0 A, or more or from about 10.0 A to about 120.0 A, or more or from about 15.0 A to about 110.0 A, or more or from about 25.0 A to about 100.0 A, or more. In some embodiments, the constant current threshold is from 0.0 to about 20.0 A, including from 0.0 to about 18.0 or from about 1.0 to about 15.0 A or from about 3.0 to about 12.0 A. In some embodiments, the constant current threshold varies by from about 0.1% to about 5% based on the measured current, including from about 0.5% to about 5% or from about 0.4% to about 4.5% or from about 0.8% to about 4.0% or from about 1.0% to about 5% or from about 1.0% to about 4%. In some embodiments, reducing the DC potential between the anode and cathode to 0.0 V includes disconnecting the DC voltage supply from the modular anode, the cathode, or a combination thereof.

[0070] In some embodiments, the method comprises forming a dechlorinated solution from the hydrogen generation solution by sequestering CF onto or near the modular anode while applying the DC voltage of about 0.5 V to about 3.0 V across the modular anode and the cathode. In some embodiments, a 1.0 L sample of the dechlorinated solution has a lower Cl- concentration than a 1.0 L sample of the hydrogeneration solution. In some embodiments, the dechlorinated solution C1‘ concentration is from about 10% to about 99% lower than a hydrogen generation solution CF concentration.

[0071] In some embodiments, the method includes: before regenerating a capacitance of the carbon containing material or before reducing a capacitance of the carbon containing material, removing the hydrogen generation solution or the dechlorinated solution from the electrochemical system; or separating the dechlorinated solution from the hydrogen generationChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT solution or the regeneration solution. In some embodiments, the method comprises harvesting the hydrogen gas from the electrochemical system, or harvesting the hydrogen gas from the electrochemical system at a rate of about 1 kg / day to about 20 kg / day per cell.

[0072] Embodiments of the electrochemical system of the present disclosure can, by replacing the conventional anode with a capacitive or modular anode as disclosed herein, eliminate the half-cell reaction that would normally occur at the anode (reduction amounting to about 60% of the voltage needed), aid in dramatically reducing the overall energy consumption by about 40% to about 60% (estimated about 33 kWh / kg when compared to about 54 kWh / kg in a conventional two-electrode electrochemical cells for producing the hydrogen gas), while eliminating the generation of oxygen and hence, precluding the need for purification of the hydrogen gas. Thus, embodiments of the electrochemical system herein can produce a large volume of dechlorinated or deionized water, serving to reclaim the water that may not be suitable for drinking or other agricultural applications.

[0073] The reference, to the extent that it provide exemplary procedural or other details supplementary to those set forth herein, is specifically incorporated herein in its entirety by express reference thereto: U.S. Patent No. 6,350,520 to Nesbitt et al., entitled “Consolidated amorphous carbon materials, their manufacture and use.”Further Embodiments

[0074] Embodiment 1. An electrochemical system comprising:

[0075] an electrical device, wherein the electrical device includes a modular anode electrically connected to a cathode and a power source, wherein the modular anode and the cathode are in contact with a hydrogen generation solution or a regeneration solution, wherein the modular anode includes a carbon containing material bound to a conductive support, wherein the carbon containing material has a specific surface area of from about 250 m2 / g to about 3,000 m2 / g.

[0076] Embodiment 2. The electrochemical system of one or more of embodiments 1-6, wherein the carbon containing material includes carbon nanotubes, fullerenes, graphene, an activated carbon material, or a combination thereof; or wherein from about 80% to 100% of a weight of the carbon containing material includes carbon nanotubes, fullerenes, graphene, an activated carbon material, or a combination thereof, based on a total weight of the carbon containing material; or wherein the carbon containing material includes a carbon containing panel bound to the conductive support by a conductive adhesive; or wherein the carbon containing material has a specific capacitance measuring from about 10 F / g to about 80 F / g whenChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT measured by cyclic voltammetry; or wherein the carbon containing material has a specific capacitance measuring from about 50 F / g to about 60 F / g when measured by cyclic voltammetry.

[0077] Embodiment 3. The electrochemical system of one or more of embodiments 1-6, wherein the carbon containing material has a specific surface area of from about 250 m2 / g to about 2,500 m2 / g, or the carbon containing material has a specific surface area of from about 250 m2 / g to about 2,000 m2 / g, or the carbon containing material has a specific surface area of from about 500 m2 / g to about 2,500 m2 / g, or the carbon containing material has a specific surface area of from about 500 m2 / g to about 2,000 m2 / g.

[0078] Embodiment 4. The electrochemical system of one or more of embodiments 1-6, wherein the carbon containing material includes a carbon containing panel bound to the conductive support by a conductive adhesive, and wherein the modular anode includes from 1 to 100 modular anodes, and from about 30% to 100% of the modular anodes, based on a total amount of modular anodes, include the carbon containing panel, and wherein the carbon containing panel has a panel longest dimension of from about 10.0 cm to about 20.0 cm and a panel shortest dimension of from about 0.64 cm to about 1.27 cm; or wherein the carbon containing panel has a rectangular shape, having a panel height, panel width, or combination thereof of from about 10.0 cm to about 20.0 cm, and a panel thickness of from about 0.64 cm to about 1.27 cm; or wherein the carbon containing panel has a panel longest dimension of from about 305.0 cm to about 3,050.0 cm and a panel shortest dimension of from about 19.0 cm to about 190.0 cm; or wherein the carbon containing panel has a rectangular shape having a panel height, a panel width, or combination thereof of from about 305.0 cm to about 3,050.0 cm and a panel thickness of from about 19.0 cm to about 190.0 cm.

[0079] Embodiment 5. The electrochemical system of one or more of embodiments 1-6, wherein the cathode includes a platinum alloy or a platinum alloy; or wherein the conductive support includes titanium, aluminum, nickel, a stainless steel, an iron-chrome alloy, or alloys thereof; or wherein the conductive adhesive includes conductive particles suspended in an epoxy, wherein the conductive particles include a metal particle, a carbon particle, or a combination or mixture and the thereof; wherein the electrochemical system includes a liquid container that contains the hydrogen generation solution or the regeneration solution without a solid barrier, a gel barrier, or a membrane barrier located between the modular anode and the cathode. Embodiment 6. The electrochemical system of one or more of embodiments 1-6, wherein the hydrogen generation solution includes water, or water and NaCl; or wherein the hydrogen generation solution includes water and CF; or wherein the regeneration solution includes water and FeSCh, Fe2(SO4)3, SnSCh, SnSCh, As, As2(SO4)s, SeCh, SeCh, or combinations or mixturesChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT thereof; or wherein the regeneration solution includes water and Fe+2, Fe+3, Sn+2, Sn+3, As, As+2, Se+2, Se+3, or combinations or mixtures thereof.

[0080] Embodiment 7. A method of generating a hydrogen gas comprising:

[0081] providing an electrochemical system that includes an electrical device, wherein the electrical device includes a modular anode electrically connected to a cathode and a power source, wherein the modular anode and the cathode are in contact with a hydrogen generation solution or a regeneration solution,

[0082] wherein the modular anode includes a carbon containing material bound to a conductive support, wherein the carbon containing material has a specific surface area of from about 250 m2 / g to about 3,000 m2 / g;

[0083] generating the hydrogen gas at the cathode by contacting the modular anode and the cathode with a hydrogen generation solution and applying a constant DC potential of about 0.5 V to about 3.0 V across the modular anode and the cathode until the measured current between the modular anode and the cathode increases to a hydrogen generation peak current and then passes from the hydrogen generation peak current to a constant current threshold; and

[0084] regenerating a capacitance of the carbon containing material by reducing a DC potential between the anode and cathode to 0.0 V and by reacting the carbon containing material with a regeneration solution, or

[0085] reducing a capacitance of the carbon containing material by reacting the modular anode with a regeneration solution.

[0086] Embodiment 8. The method of one or more of embodiments 7-15, further comprising, before regenerating a capacitance of the carbon containing material or before reducing a capacitance of the carbon containing material, providing a regeneration solution by adding a reducing agent to an aqueous solution, wherein the aqueous solution is the hydrogen generation solution or a pre-regeneration aqueous solution.

[0087] Embodiment 9. The method of one or more of embodiments 7-15, wherein the reducing agent is FeSCh, SnSCh, As, SeCh, Fe+2, Sn+2, Se+2, or combinations or mixtures thereof.

[0088] Embodiment 10. The method of one or more of embodiments 7-15, further comprising, forming Fe+3, Sn+3, As+2, Se+3, or a combination or mixture thereof, by reacting the reducing agent with the modular anode.

[0089] Embodiment 11. The method of one or more of embodiments 7-15, wherein the constant DC potential varies by from 0.0 to 0.2 V while hydrogen is generated from the cathode; or wherein the hydrogen generation peak current is from about 1.0 A to about 150.0 A or more; or the constant current threshold is from 0.0 to about 20.0 A and varies by from 0.1% to aboutChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT5% based on the measured current; or wherein reducing the DC potential between the anode and cathode to 0.0 V includes disconnecting the DC voltage supply from the modular anode, the cathode, or a combination thereof.

[0090] Embodiment 12. The method of one or more of embodiments 7-15, further comprising, forming a dechlorinated solution from the hydrogen generation solution by sequestering Cl’ onto or near the modular anode while applying the DC voltage of about 0.5 V to about 3.0 V across the modular anode and the cathode, wherein a 1 L sample of the dechlorinated solution has a lower Cl’ concentration than a 1 L sample of the hydrogeneration solution.

[0091] Embodiment 13. The method of one or more of embodiments 7-15, wherein a dechlorinated solution Cl’ concentration is from about 10% to 99% lower than a hydrogen generation solution Cl’ concentration.

[0092] Embodiment 14. The method of one or more of embodiments 7-15, further comprising, before regenerating a capacitance of the carbon containing material or before reducing a capacitance of the carbon containing material, removing the hydrogen generation solution or the dechlorinated solution from the electrochemical system; or separating the dechlorinated solution from the hydrogen generation solution or the regeneration solution.15. Embodiment The method of one or more of embodiments 7-15, further comprising, harvesting the hydrogen gas from the electrochemical system, or harvesting the hydrogen gas from the electrochemical system at a rate of about 1 kg / day to about 20 kg / day per cell.EXAMPLESExample 1Large Surface Area Anode

[0093] A large surface area electrode material was used as an anode for the production of hydrogen from water. To be efficient, a suitable material should have a large (Brunauer-Emmett- Teller (BET) surface area (such as a granular activated carbon) and still be electrically conductive and attached to a metal plate which acts as the current collector to distribute the electric current evenly throughout the material. A large porous, solid block of activated carbon (AC) was obtained from Reticle, Inc. (“Reticle Carbon,” Los Altos Hills, CA). Suitable porous, solid block of activated carbon can be provided according to procedures disclosed in U.S. Patent No. 6,350,520, which is incorporated by reference in its entirety. The AC has recorded surface areas from 1200 m2 / g to as high as 1900 m2 / g (as measured in a nitrogen BET analyzer).Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCTBecause the individual AC particles are interconnected by the consolidation process, this material has uniform, isotropic properties of electrical conductivities, while maintaining a large proportion of the original surface areas of the precursor AC. Some AC samples have measured electrical conductivities approaching the conductivity of elemental lead (4000 S / cm). The high electrical conductivity coupled with the high surface area makes this material suitable for this.Cell Construction

[0094] While the cell is believed to be completely scalable (from bench-size to full-size) this example used a small cell for the demonstration of the technology. An electrolysis cell with an interior dimension of 4” (10.1 cm) by 5” (12.7 cm) by 10” (25.4 cm) was manufactured from high density polyethylene (HDPE). The cell had grooves machined along the sides for sliding titanium plates into the cell; the slots were spaced approximately %” (1.9 cm) apart along both of the long sides of the cell. Copper strips were placed on the top of the long sides of the cell; small holes were punched through so that small bolts and nuts could be used to secure metal plates to the copper piece. The copper pieces can act as bus bars to allow the addition of current to all of the like plates (cathodes and anodes) from the power supply. An outlet pipe was placed in the discharge side of the cell at a position that would maintain a constant level of fluid in the cell. A variable speed pump was used to feed water through the cell on the side opposite the discharge port.

[0095] The electrode plates were constructed from titanium sheet (approximately 1 mm thick). Anode plates were made with an extended piece welded to the top that extended a short distance from the left edge of each anode plate. The cathode plates were made with a small extension above the left and top edge of the electrode surface; a flat piece of titanium was then welded on the extended top which extended away from the plate a distance similar to that of the anodes. This arrangement allowed the cathodes to be fully submerged in the cell, with the flat piece just hitting the top edge of the cell. The electrode plates were arranged so that all of the anode pieces were parallel with the flat piece aligned to the left of the cell; all cathode pieces were arranged with the flat tab facing to the right. Electrodes were alternately placed in the cell so that the first electrode was placed with its bottom edge on the bottom of the cell, with the top edge approximately 1” (2.5 cm) below the water line of the cell. The next plate was suspended approximately 1” (2.5 cm) above the bottom of the cell. A total of 4 submerged plates and 3 suspended plates were alternately placed in the cell. A pump was employed to circulate the water through the cell. The pump feed came from a container under the discharge with the discharge being recirculated back to the feed end of the cell. With this arrangement, water wouldChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT hydraulically flow over and under each pair of electrodes in a manner that maintained a constant flow between each electrode pair. The pump was metered to add approximately 100-mL of solution through the small cell assembly; with the electrodes in place, the total volume of fluid in the electrolysis cell was approximately 1 L.

[0096] The anodes were further prepared to hold the large surface area carbon. Small plates of AC (with ~ 1400 m2 / g interfacial surface area) were cut and smoothed into uniform pieces with a final dimension of 3.5” (8.9 cm) x4” (10.2 cm) x 0.25” (0.6 cm). Each of these pieces were adhered to both sides of the anodes such that all of the carbon would be submerged on the plates that were suspended above the bottom of the cell. A conductive 2-part epoxy (a suitable conductive 2-part epoxy can be obtained from MG Chemicals 833 ID, MG CHEMICALS®, Burlington, Ontario, Canada) was applied to each surface of the anode; the epoxy contained fine carbon particles and minute copper particles to enhance the electrical conductivity of the epoxy, but did not hinder the bonding of the two parts when mixed. The fully submerged plates were to be used as cathodes. The tabs on both the anodes and cathodes were extended so that each would be touching a copper piece on either side of the cell. The anodes were all contacting one copper piece, while all of the cathodes were connected to the other copper piece. These copper pieces were then connected to the power supply to conduct the current to and from the electrodes equally.Hydrogen Generation

[0097] A DC-power supply was used with a variable voltage, but constant current mode (variable 0-5 V potential with a maximum 40 Amp output). The negative pole piece was wired to the copper cathode bus, and the positive pole piece was wired to the copper anode bus. An ammeter was installed on the cathode wire from the power supply. Saline water (with -1000 ppm NaCl) was then circulated through the cell, and thus the electrode pairs. The DC power supply was ramped up to a voltage that supported a steady amperage to the cell, and was immediately shut off. The first voltage was approximately 1.2-V used in this demonstration.

[0098] The water flow was verified to be flowing at approximately 100 mL per minute, and the ammeter was attached to the cathode lead wire, and the power started. Immediately the amperage rose to nearly 40 amps (the maximum output of the power supply used), and bubbles began to form on the cathode. A lit match was used to confirm that the gas was indeed hydrogen. The cell proceeded to draw current, but the current rate slowed after several minutes (from 40 amps to about 25 amps in about 30 minutes). As the capacitance of the large carbon electrodes began to adsorb anions (presumably chlorides) the current draw started to dropChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT consistently. Once the anodes were “loaded”, the current draw settled to a few milliamps, and the test was considered complete. No oxygen was detected from the anodes, only hydrogen was observed from the cathodes. The filling of the capacitance supplied by the carbon on the anodes was able to replace the oxidation of water to form oxygen at considerably lower cell potential than would be needed to generate both hydrogen and oxygen from water. The formation of hydrogen exactly corresponded with the flow of current. That is, as the current was peaked, hydrogen generation was at its peak; as the current dropped as the capacitor filled, so did the hydrogen generation ebb.Regeneration

[0099] The power supply was turned off and disconnected, and the saline solution was poured out of the cell. A ferrous sulfate solution was poured into the cell. This solution was circulated through the cell for several minutes to fully replace the volume of the cell (~ 1 L) several times through the pump. The solution was discarded, and the salt water was returned to the cell, and the power supply was again started. The ferrous salts were able to “regenerate” the carbon by removing the oxidation potential that was stored on the anode interface. Another generation of hydrogen was then commenced.Second Hydrogen Generation Step

[0100] The settings from the previous hydrogen generation step were resumed, and hydrogen was again observed coming from the cell.Example 2

[0101] The steps of Example 1 would be repeated, except a cell with approximately 1 ft (30.5 cm) X 1 -ft (30.5 cm) cross-section and more than 40 pairs of electrodes has been used in desalinating water by adsorbing ions to both cathode and anode pairs containing AC Reticle Carbon. This cell would be used in much the same manner as Example 1, replacing the Reticle Carbon cathodes with plates of titanium or possibly stainless steel.Example 3

[0102] The steps of Example 1 would be repeated, except an even larger cell would been constructed with 3-ft (91.4 cm) X 3-ft (91.4 cm) and over 30 pairs of electrodes that could also be retrofit to generate hydrogen.Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCT Example 4

[0103] The steps of Example 1 would be repeated, except, in order to better collect hydrogen, a sealed, vented canopy would be added to reduce or prevent outside air from being pulled with the hydrogen.

Claims

Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCTCLAIMSWhat is claimed is:

1. An electrochemical system comprising: an electrical device, wherein the electrical device includes a modular anode electrically connected to a cathode and a power source, wherein the modular anode and the cathode are in contact with a hydrogen generation solution or a regeneration solution, wherein the modular anode includes a carbon containing material bound to a conductive support, wherein the carbon containing material has a specific surface area of from about 250 m2 / g to about 3,000 m2 / g.

2. The electrochemical system of claim 1, wherein the carbon containing material includes carbon nanotubes, fullerenes, graphene, an activated carbon material, or a combination thereof; or wherein from about 80% to 100% of a weight of the carbon containing material includes carbon nanotubes, fullerenes, graphene, an activated carbon material, or a combination thereof, based on a total weight of the carbon containing material; or wherein the carbon containing material includes a carbon containing panel bound to the conductive support by a conductive adhesive; or wherein the carbon containing material has a specific capacitance measuring from about 10 F / g to about 80 F / g when measured by cyclic voltammetry; or wherein the carbon containing material has a specific capacitance measuring from about 50 F / g to about 60 F / g when measured by cyclic voltammetry.

3. The electrochemical system of claim 1, wherein the carbon containing material has a specific surface area of from about 250 m2 / g to about 2,500 m2 / g, or the carbon containing material has a specific surface area of from about 250 m2 / g to about 2,000 m2 / g, or the carbon containing material has a specific surface area of from about 500 m2 / g to about 2,500 m2 / g, or the carbon containing material has a specific surface area of from about 500 m2 / g to about 2,000 m2 / g.

4. The electrochemical system of claim 1, wherein the carbon containing material includes a carbon containing panel bound to the conductive support by a conductive adhesive, and wherein the modular anode includes from 1 to 100 modular anodes, and from about 30% to 100% of the modular anodes, based on a total amount of modular anodes, include the carbon containing panel, andChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT wherein the carbon containing panel has a panel longest dimension of from about 10.0 cm to about 20.0 cm and a panel shortest dimension of from about 0.64 cm to about 1.27 cm; or wherein the carbon containing panel has a rectangular shape, having a panel height, panel width, or combination thereof of from about 10.0 cm to about 20.0 cm, and a panel thickness of from about 0.64 cm to about 1.27 cm; or wherein the carbon containing panel has a panel longest dimension of from about 305.0 cm to about 3,050.0 cm and a panel shortest dimension of from about 19.0 cm to about 190.0 cm; or wherein the carbon containing panel has a rectangular shape having a panel height, a panel width, or combination thereof of from about 305.0 cm to about 3,050.0 cm and a panel thickness of from about 19.0 cm to about 190.0 cm.

5. The electrochemical system of claim 1, wherein the cathode includes a platinum alloy or a platinum alloy; or wherein the conductive support includes titanium, aluminum, nickel, a stainless steel, an iron-chrome alloy, or alloys thereof; or wherein the conductive adhesive includes conductive particles suspended in an epoxy, wherein the conductive particles include a metal particle, a carbon particle, or a combination or mixture and the thereof; wherein the electrochemical system includes a liquid container that contains the hydrogen generation solution or the regeneration solution without a solid barrier, a gel barrier, or a membrane barrier located between the modular anode and the cathode.

6. The electrochemical system of claim 1, wherein the hydrogen generation solution includes water, or water and NaCl; or wherein the hydrogen generation solution includes water and Cl’; or wherein the regeneration solution includes water and FeSCh, Fe2(SO4)3, SnSCh, SnSCh, As, AS2(SO4)S, SeCh, SeCh, or combinations or mixtures thereof; or wherein the regeneration solution includes water and Fe+2, Fe+3, Sn+2, Sn+3, As, As+2, Se+2, Se+3, or combinations or mixtures thereof.

7. A method of generating a hydrogen gas comprising: providing an electrochemical system that includes an electrical device, wherein the electrical device includes a modular anode electrically connected to a cathode and a powerChilds Patent Law PLLC Attorney Docket No. : ReticleHgPCT source, wherein the modular anode and the cathode are in contact with a hydrogen generation solution or a regeneration solution, wherein the modular anode includes a carbon containing material bound to a conductive support, wherein the carbon containing material has a specific surface area of from about 250 m2 / g to about 3,000 m2 / g; generating the hydrogen gas at the cathode by contacting the modular anode and the cathode with a hydrogen generation solution and applying a constant DC potential of about 0.5 V to about 3.0 V across the modular anode and the cathode until the measured current between the modular anode and the cathode increases to a hydrogen generation peak current and then passes from the hydrogen generation peak current to a constant current threshold; and regenerating a capacitance of the carbon containing material by reducing a DC potential between the anode and cathode to 0.0 V and by reacting the carbon containing material with a regeneration solution, or reducing a capacitance of the carbon containing material by reacting the modular anode with a regeneration solution.

8. The method of claim 7, further comprising, before regenerating a capacitance of the carbon containing material or before reducing a capacitance of the carbon containing material, providing a regeneration solution by adding a reducing agent to an aqueous solution, wherein the aqueous solution is the hydrogen generation solution or a pre-regeneration aqueous solution.

9. The method of claim 8, wherein the reducing agent is FeSCh, SnSCh, As, SeCh, Fe+2, Sn+2, Se+2, or combinations or mixtures thereof.

10. The method of claim 9, further comprising, forming Fe+3, Sn+3, As+2, Se+3, or a combination or mixture thereof, by reacting the reducing agent with the modular anode.

11. The method of claim 7, wherein the constant DC potential varies by from 0.0 to 0.2 V while hydrogen is generated from the cathode; or wherein the hydrogen generation peak current is from about 1.0 A to about 150.0 A or more; or the constant current threshold is from 0.0 to about 20.0 A and varies by from 0.1% to about 5% based on the measured current; or wherein reducing the DC potential between the anode and cathode to 0.0 V includes disconnecting the DC voltage supply from the modular anode, the cathode, or a combination thereof.Childs Patent Law PLLC Attorney Docket No. : ReticleHgPCT12. The method of claim 7, further comprising, forming a dechlorinated solution from the hydrogen generation solution by sequestering Cl’ onto or near the modular anode while applying the DC voltage of about 0.5 V to about 3.0 V across the modular anode and the cathode, wherein a 1 L sample of the dechlorinated solution has a lower Cl’ concentration than a 1 L sample of the hydrogeneration solution.

13. The method of claim 12, wherein a dechlorinated solution Cl’ concentration is from about 10% to 99% lower than a hydrogen generation solution Cl’ concentration.

14. The method of claim 13, further comprising, before regenerating a capacitance of the carbon containing material or before reducing a capacitance of the carbon containing material, removing the hydrogen generation solution or the dechlorinated solution from the electrochemical system; or separating the dechlorinated solution from the hydrogen generation solution or the regeneration solution.

15. The method of claim 7, further comprising, harvesting the hydrogen gas from the electrochemical system, or harvesting the hydrogen gas from the electrochemical system at a rate of about 1 kg / day to about 20 kg / day per cell.

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