Device for producing organic hydride, system for producing organic hydride, and method for reusing migration water

Abstract

A device for producing an organic hydride according to the present invention produces the organic hydride in an electrolytic cell comprising an electrolyte membrane, an anode disposed on one side of the electrolyte membrane, and a cathode disposed on the other side of the electrolyte membrane, said device being equipped with: an anolyte supply part for supplying an anolyte to the anode; and an aeration part in which a gas including at least one of oxygen and nitrogen is supplied as an aeration gas to migration water separated from a catholyte and organic matter dissolved in the migration water is separated therefrom, and from which the migration water having a reduced concentration of dissolved organic matter is supplied to the anolyte supply part.

Description

Organic hydride production apparatus, organic hydride production system, and method for reusing transition water

[0001] The present invention relates to an organic hydride manufacturing apparatus, an organic hydride manufacturing system, and a method for recycling transition water.

[0002] In recent years, in order to reduce carbon dioxide emissions during the energy generation process, there has been a demand for the widespread use of renewable energy obtained from solar, wind, hydroelectric, geothermal, etc. The use of an organic hydride production apparatus that produces organic hydrides as an energy carrier for transporting and storing hydrogen derived from the obtained renewable energy has been considered.

[0003] As an organic hydride production apparatus, for example, an organic hydride production apparatus has been proposed that includes a cathode catalyst layer that reduces a substance to be hydrided, an anode catalyst layer that oxidizes water, and a solid polymer electrolyte membrane disposed between the cathode catalyst layer and the anode catalyst layer (see, for example, Patent Document 1).

[0004] In an organic hydride manufacturing apparatus, water is supplied to the anode, and a material to be hydrogenated is supplied to the cathode. When a voltage is applied between the anode and the cathode, protons generated by the electrolysis of water at the anode undergo a hydrogenation reaction with the material to be hydrogenated at the cathode, hydrogenating the material. This produces an organic hydride in which hydrogen has been added to the material to be hydrogenated.

[0005] Japanese Patent Application Publication No. 2012-72477

[0006] In conventional organic hydride production apparatuses such as the organic hydride production apparatus of Patent Document 1, a large amount of transition water is generally generated in the cathode catalyst layer along with the production of organic hydride. The transition water contained in the cathode fluid discharged from the electrolytic cell is separated at the interface formed between the material to be hydrided and the organic material such as the organic hydride, and is used for the anode fluid supplied to the anode catalyst layer on the anode electrode side.

[0007] However, the catholyte may contain organic matter dissolved in the transition water in addition to the organic matter that forms an interface with the transition water. Therefore, in order to reuse the transition water separated from the catholyte as an anode fluid or the like, it is necessary to remove the organic matter dissolved in the transition water separated from the catholyte.

[0008] An object of one aspect of the present invention is to provide an organic hydride manufacturing apparatus capable of reducing the concentration of organic substances dissolved in transition water contained in a catholyte discharged from an electrolytic cell.

[0009] One aspect of the present invention is an organic hydride manufacturing apparatus that manufactures an organic hydride in an electrolytic cell having an electrolyte membrane, an anode electrode installed on one side of the electrolyte membrane, and a cathode electrode installed on the other side of the electrolyte membrane, the organic hydride manufacturing apparatus comprising: an anode fluid supply unit that supplies an anode fluid to the anode electrode; and an aeration unit that supplies a gas containing at least one of oxygen and nitrogen as an aeration gas to transition water separated from the cathode fluid, thereby separating organic matter dissolved in the transition water, and supplying the transition water with a reduced concentration of dissolved organic matter to the anode fluid supply unit.

[0010] One aspect of the present invention is an organic hydride production system comprising: an organic hydride production apparatus that produces an organic hydride in an electrolytic cell having an electrolyte membrane, an anode electrode installed on one side of the electrolyte membrane, and a cathode electrode installed on the other side of the electrolyte membrane; a power supply unit that supplies power to the electrolytic cell; and a power supply unit that supplies power to the organic hydride production apparatus, wherein the organic hydride production apparatus comprises: an anolyte supply unit that supplies anolyte to the anode electrode; an aeration unit that supplies a gas containing at least one of oxygen and nitrogen as an aeration gas to transferred water separated from the cathode liquid to separate organic matter dissolved in the transferred water; and a line that connects the aeration unit to the anolyte supply unit.

[0011] One aspect of the present invention is a method for recycling transition water in an electrolytic cell for producing organic hydride, the method comprising: an aeration step of supplying a gas containing at least one of oxygen and nitrogen as an aeration gas to transition water separated from cathode fluid discharged from the electrolytic cell, the transition water having an electrolyte membrane, an anode electrode installed on one side of the electrolyte membrane, and a cathode electrode installed on the other side of the electrolyte membrane, to separate organic matter dissolved in the transition water; and a circulation step of supplying the transition water, in which the concentration of dissolved organic matter has been reduced, to an anode fluid supply unit that supplies anode fluid to the anode electrode.

[0012] One aspect of the present invention can reduce the concentration of organic matter dissolved in transition water contained in the catholyte discharged from the electrolytic cell.

[0013] It is a schematic diagram showing the schematic configuration of an organic hydride manufacturing system including an organic hydride manufacturing apparatus according to a first embodiment of the present invention. It is a diagram showing a schematic example of the configuration of an electrolytic cell. It is a schematic diagram showing the schematic configuration of an organic hydride manufacturing system including an organic hydride manufacturing apparatus according to a second embodiment of the present invention. It is a schematic diagram showing the schematic configuration of an organic hydride manufacturing system including an organic hydride manufacturing apparatus according to a third embodiment of the present invention.

[0014] Hereinafter, embodiments of the present invention will be described in detail. To facilitate understanding of the description, the same components in each drawing will be denoted by the same reference numerals, and duplicate explanations will be omitted. In this specification, unless otherwise specified, "to" indicating a numerical range means that the numerical values ​​before and after it are included as the lower and upper limits. Furthermore, when a unit is specified for only the upper limit value in a numerical range expressed by "to", it means that the lower limit value is also in the same unit.

[0015] <First Embodiment> [Organic Hydride Production System] An organic hydride production system including an organic hydride production apparatus according to a first embodiment of the present invention (hereinafter simply referred to as "this embodiment") will be described. Fig. 1 is a schematic diagram showing a general configuration of an organic hydride production system including an organic hydride production apparatus according to the first embodiment. As shown in Fig. 1, the organic hydride production system 1A according to the first embodiment includes a power supply unit 10 and an organic hydride production apparatus 20A, and produces organic hydride in the organic hydride production apparatus 20A using power supplied from the power supply unit 10.

[0016] In conventional organic hydride manufacturing apparatuses, transition water, which migrates with protons from the anode electrode side to the cathode electrode side, is generally discharged from the electrolytic cell together with the cathode fluid. The transition water may contain dissolved organic matter, such as the material to be hydrogenated in the cathode fluid and organic hydrides produced in the electrolytic cell. In the organic hydride manufacturing system 1A, the organic matter dissolved in the transition water can be accurately separated in the aeration tank 251 of the organic hydride manufacturing apparatus 20A, thereby reducing the concentration of the organic matter dissolved in the transition water. Therefore, the organic hydride manufacturing system 1A can effectively use the transition water with a reduced concentration of organic matter as the anode fluid AL, etc.

[0017] (Power supply unit) The power supply unit 10 is a power supply device that supplies direct current power to the power supply unit 22 of the organic hydride manufacturing apparatus 20A, and has at least one of a first power supply unit 11 and a second power supply unit 12, and may also have a power conversion unit 13.

[0018] The first power supply unit 11 generates electricity derived from renewable energy. The first power supply unit 11 may be any power generation device that generates electricity using renewable energy, and may be, for example, a wind power generation device, a solar power generation device, a hydroelectric power generation device, a geothermal power generation device, a wave power generation device, a temperature difference power generation device, or a biomass power generation device.

[0019] The second power supply unit 12 can be configured as a storage battery, a thermal power plant that burns fossil fuels such as natural gas and coal, or the like. The power of the second power supply unit 12 may be used as a secondary power when the power supplied from the first power supply unit 11 is insufficient. As a result, the organic hydride manufacturing apparatus 20A can stably operate by supplying power from the second power supply unit 12 to the electrolytic cell 21 in addition to the power from the first power supply unit 11. Furthermore, when the second power supply unit 12 is configured as a storage battery, the second power supply unit 12 is charged by receiving power from the first power supply unit 11, thereby reducing the CO2 generated by the power supply unit 10. ２ The second power supply unit 12 may supply power to the power supply unit 22 independently of the first power supply unit 11. The second power supply unit 12 may supply power to the power supply unit 22 under the control of the control unit 27.

[0020] In addition, the power supply unit 10 may be equipped with a storage battery, store the electricity generated by at least one of the first power supply unit 11 and the second power supply unit 12, and supply electricity from the storage battery to the organic hydride manufacturing apparatus 20A as needed.

[0021] The power conversion unit 13 converts the output voltage of the first power supply unit 11 into a predetermined voltage. For example, a DC / DC converter or the like is used as the power conversion unit 13. When AC power is input from the first power supply unit 11, the power conversion unit 13 converts the voltage using a transformer, rectifies the voltage using a bridge-type diode, smooths the voltage using a smoothing electrolytic capacitor, and supplies the power from the output terminal to the electrolytic cell 21. Note that the power conversion unit 13 may also convert the output voltage of the second power supply unit 12 into a predetermined voltage.

[0022] In the organic hydride manufacturing system 1A, when the power supply unit 10 supplies power from the first power supply unit 11, i.e., power generated by the first power supply unit 11, to the electrolytic cell 21 of the organic hydride manufacturing apparatus 20A, the organic hydride manufacturing apparatus 20A operates, and when power from the first power supply unit 11 is not supplied to the electrolytic cell 21, the organic hydride manufacturing apparatus 20A may stop operating.

[0023] The term "operation" refers to the time when the organic hydride manufacturing apparatus 20A is producing an organic hydride, which is the main purpose of the organic hydride manufacturing apparatus 20A. Therefore, even when the organic hydride manufacturing apparatus 20A is out of operation, power may be supplied to the organic hydride manufacturing apparatus 20A from the second power supply unit 12.

[0024] (Organic Hydride Manufacturing Apparatus) The organic hydride manufacturing apparatus 20A includes an electrolytic cell 21, a power supply unit 22, an anolyte supply unit 23, a catholyte supply unit 24, an aeration unit 25A, a measurement unit 26, and a control unit 27, and hydrogenates the substance to be hydrided in the catholyte CL with protons generated by electrolysis of water in the anolyte AL through a hydrogenation reaction (hereinafter also referred to as an "electrochemical reduction reaction"), thereby manufacturing an organic hydride.

[0025] ((Electrolytic Cell)) The electrolytic cell 21 is an electrolytic cell that hydrogenates a substance to be hydrogenated, which is a dehydrogenated form of an organic hydride, by an electrochemical reduction reaction to produce an organic hydride.

[0026] 2 is a diagram schematically illustrating an example of the configuration of the electrolytic cell 21. As shown in FIG. 2, the electrolytic cell 21 includes a membrane electrode assembly 31, a plate member 32, and a gasket 33.

[0027] The membrane electrode assembly 31 includes an electrolyte membrane 311 , an anode electrode 312 , and a cathode electrode 313 which is a reduction electrode, and may also include a current collector 314 .

[0028] The electrolyte membrane 311 is disposed between the anode electrode 312 and the cathode electrode 313, and separates the anode electrode 312 from the cathode electrode 313. The electrolyte membrane 311 allows protons to move from the anode electrode 312 side to the cathode electrode 313 side, and also allows water to move as migration water.

[0029] The term "migrated water" refers to water contained in the anode fluid AL that has migrated from the anode chamber 34 to the cathode chamber 35 through the electrolyte membrane 311.

[0030] The electrolyte membrane 311 is made of a proton-conductive material and selectively conducts protons. For example, a solid polymer electrolyte membrane made of a proton-conductive material can be used as the electrolyte membrane 311. The solid polymer electrolyte membrane is not particularly limited as long as it is made of a proton-conductive material and can be appropriately selected depending on the purpose. An example of the solid polymer electrolyte membrane is a fluorine-based ion exchange membrane having a sulfonic acid group.

[0031] As a proton-conductive material, for example, a polymer having cation-exchange type proton conductivity (proton-conducting polymer) is used. Examples of proton-conducting polymers include perfluorosulfonic acid polymers such as Nafion (registered trademark) and Flemion (registered trademark). The ion exchange capacity (IEC) of the cation-exchange type ionomer is preferably 0.7 to 2 meq / g. If the ion exchange capacity of the proton-conducting polymer is 0.7 meq / g or more, the electrolyte membrane 311 has sufficient ion conductivity. If the ion exchange capacity of the proton-conducting polymer is 2 meq / g or less, the increase in the solubility of the proton-conducting polymer in water is suppressed, and the electrolyte membrane 311 has sufficiently high strength.

[0032] The thickness of the electrolyte membrane 311 is not particularly limited and may be selected appropriately, but is preferably 5 to 300 μm, for example. If the thickness of the electrolyte membrane 311 is 5 μm or more, the barrier properties of the electrolyte membrane 311 can be maintained and the amount of cross leakage can be reduced. Furthermore, if the thickness of the electrolyte membrane 311 is 300 μm or less, excessive ion migration resistance can be prevented.

[0033] The area resistance of the electrolyte membrane 311, i.e., the ion transfer resistance per geometric area, is 2000 mΩ cm ２ The contact resistance of the electrolyte membrane 311 is preferably 2000 mΩ·cm or less. ２ If it is higher, the proton conductivity will be insufficient.

[0034] The anode electrode 312 is provided so as to be in contact with one main surface (the left main surface in FIG. 2 ) of the electrolyte membrane 311. The anode electrode 312 is an electrode that oxidizes water in the anolyte AL to generate protons. The anode electrode 312 is sometimes referred to as an anode catalyst layer.

[0035] The anode electrode 312 includes an anode catalyst that oxidizes water.

[0036] Examples of the anode catalyst include metals such as Ir, Ru, Pt, Pd, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Sn, W, Re, Pb, and Bi, as well as oxides of these metals. Among these, Ir, Ru, Pt, and oxides of these metals are preferred in terms of improving the electrode reaction of the anode electrode 312 and efficiently hydrogenating the material to be hydrogenated. Examples of these metal oxides include RuO ２ and IrO ２ etc. are used.

[0037] The anode catalyst may be dispersed and supported on or coated on an electronically conductive substrate. The substrate may be composed of, for example, a metal such as Ti, Zr, Nb, Mo, Hf, Ta, or W, or an oxide thereof, or a material containing a metal as a main component such as stainless steel (SUS). The substrate may be in the form of a wire, a woven or nonwoven sheet, a mesh, a porous body, a foam, or the like.

[0038] In particular, RuO ２ and IrO ２ When RuO is used, ２ and IrO ２ is expensive, so RuO ２ and IrO ２ It is preferable to use the material by dispersing or coating it on a substrate, as this reduces the production cost.

[0039] The anode electrode 312 is housed in an anode chamber 34 defined by the electrolyte membrane 311, the plate member 32, and the gasket 33. The space in the anode chamber 34 excluding the anode electrode 312 and the current collector 314 forms a flow path through which the anolyte AL and oxygen gas generated by the electrode reaction (electrolysis reaction of water) pass. The anolyte AL is supplied to the anode chamber 34 from the anolyte tank 231 by the anode pump 233. The anolyte AL is supplied from the anode chamber 34 to the anode electrode 312.

[0040] The anolyte AL includes water to be supplied to the anode electrode 312. Examples of the anolyte AL include pure water, ion-exchanged water, and solutions having a predetermined ionic conductivity (hereinafter also referred to as "ionic conductivity aqueous solutions") such as an aqueous sulfuric acid solution, an aqueous nitric acid solution, and an aqueous hydrochloric acid solution.

[0041] The plate member 32A may have one or more grooves formed on its main surface facing the anode electrode 312, with the space between the groove and the anode electrode 312 serving as the anode chamber 34, forming a flow path through which the anolyte AL flows. The shape of the flow path is not particularly limited, and may be, for example, a linear flow path or a serpentine flow path.

[0042] The cathode electrode 313 is provided so as to be in contact with the other main surface of the electrolyte membrane 311 (the right main surface in FIG. 2 ). That is, the cathode electrode 313 is provided on the main surface of the electrolyte membrane 311 opposite to the anode electrode 312. The cathode electrode 313 is an electrode for producing an organic hydride by hydrogenating a substance to be hydrogenated with protons. The cathode electrode 313 is sometimes referred to as a cathode catalyst layer.

[0043] The cathode electrode 313 is housed in a cathode chamber 35 defined by the electrolyte membrane 311, the plate member 32, and the gasket 33. The space in the cathode chamber 35 excluding the cathode electrode 313 forms a flow path through which a cathode fluid CL containing a substance to be hydrided and hydrogen gas generated by an electrode reaction (electrochemical reduction reaction) pass. The cathode chamber 35 is supplied with the cathode fluid CL from a cathode fluid tank 241 by a cathode pump 243. The cathode chamber 35 supplies the cathode fluid CL to the cathode electrode layer 313A.

[0044] The catholyte CL contains a material to be hydrided, which is an organic hydride raw material to be supplied to the cathode electrode layer 313A.

[0045] The material to be hydrogenated is an organic compound that is hydrogenated by an electrochemical reduction reaction in the electrolytic cell 21 to become an organic hydride, that is, a dehydrogenated form of an organic hydride.

[0046] The cathode fluid CL does not contain any organic hydride before the organic hydride production system 1A starts operating, and after the operation starts, the cathode fluid CL becomes a mixed liquid of the material to be hydrided and the organic hydride by being mixed with the organic hydride produced by the electrode reaction (electrochemical reduction reaction) at the cathode electrode 313. The material to be hydrided and the organic hydride may preferably be liquid at 20°C and 1 atmosphere.

[0047] The material to be hydrogenated and the organic hydride are not particularly limited as long as they are organic compounds that can reversibly cause at least one of a hydrogenation reaction and a dehydrogenation reaction, thereby allowing at least one of adding and desorbing hydrogen gas. As the material to be hydrogenated and the organic hydride, organic compounds such as acetone-isopropanol compounds, benzoquinone-hydroquinone compounds, and aromatic hydrocarbon compounds can be used. Among these, aromatic hydrocarbon compounds are preferred from the viewpoint of transportability during energy transportation.

[0048] An aromatic hydrocarbon compound is a compound containing at least one aromatic ring. Examples of aromatic hydrocarbon compounds include benzene, alkylbenzene, naphthalene, alkylnaphthalene, anthracene, and diphenylethane. Alkylbenzenes include compounds in which 1 to 4 hydrogen atoms on the aromatic ring are substituted with a linear or branched alkyl group having 1 to 6 carbon atoms. Examples of such compounds include toluene, xylene, mesitylene, ethylbenzene, and diethylbenzene. Alkylnaphthalenes include compounds in which 1 to 4 hydrogen atoms on the aromatic ring are substituted with a linear or branched alkyl group having 1 to 6 carbon atoms. Examples of such compounds include methylnaphthalene. These compounds may be used alone or in combination.

[0049] The substance to be hydrogenated is preferably at least one of toluene and benzene. Nitrogen-containing heterocyclic aromatic compounds such as quinoline, isoquinoline, N-alkylpyrrole, N-alkylindole, and N-alkyldibenzopyrrole may also be used as the substance to be hydrogenated. Organic hydrides are those obtained by hydrogenating the above-mentioned substances to be hydrogenated, and examples thereof include cyclohexane, methylcyclohexane, dimethylcyclohexane, and decahydroquinoline.

[0050] The plate member 32B may have one or more grooves formed on its main surface facing the cathode electrode layer 313A, with the space between this groove and the liquid diffusion layer 313B serving as the cathode chamber 35, forming a flow path through which the cathode fluid CL flows. When one or more grooves are formed on its main surface facing the cathode electrode layer 313A, the plate member 32B may be configured so that its main surface facing the cathode electrode layer 313A is in contact with the liquid diffusion layer 313B. In this case, the space between the groove and the liquid diffusion layer 313B serves as the cathode chamber 35, forming a flow path through which the cathode fluid CL flows. The shape of the flow path is not particularly limited, and the same flow path as described above may be formed.

[0051] The cathode electrode 313 includes a cathode electrode layer 313A and a liquid diffusion layer 313B.

[0052] The cathode electrode layer 313A contains a cathode catalyst that hydrogenates the substance to be hydrogenated.

[0053] Examples of the cathode catalyst include Pt and Ru. The cathode electrode layer 313A may contain other metals or metal compounds.

[0054] The cathode catalyst may be supported on a catalyst support having a porous structure, which may be made of an electron-conductive material such as porous carbon, porous metal, or porous metal oxide.

[0055] The cathode catalyst may be coated with an ionomer (cation exchange ionomer), or a catalyst support supporting the cathode catalyst may be coated with an ionomer. Examples of ionomers include perfluorosulfonic acid polymers such as Nafion (registered trademark), Flemion (registered trademark), Fumion (registered trademark), and Aciplex (registered trademark). It is preferable that the ionomer partially coats the cathode catalyst. This allows the three elements (substance to be hydrided, protons, and electrons) necessary for the electrochemical reaction in the cathode electrode layer 313A to be efficiently supplied to the reaction field (cathode catalyst) of the cathode electrode layer 313A.

[0056] The liquid diffusion layer 313B is disposed on the main surface of the cathode electrode layer 313A opposite to the electrolyte membrane 311 (the right main surface in FIG. 2 ). The liquid diffusion layer 313B allows the cathode fluid CL supplied from the outside to the cathode chamber 35 to pass through and diffuse uniformly into the cathode electrode layer 313A. The organic hydride produced in the cathode electrode layer 313A is discharged into the cathode chamber 35 via the liquid diffusion layer 313B.

[0057] The liquid diffusion layer 313B is a porous body having a porous structure, such as a fibrous body, an aggregate, or a foam, and has pores therein through which a liquid (e.g., cathode fluid CL) and a gas (e.g., hydrogen gas) can pass. The cathode fluid CL passes through the liquid diffusion layer 313B and reaches the cathode electrode layer 313A, where an organic hydride is produced from the substance to be hydrided. The organic hydride produced in the cathode electrode layer 313A, hydrogen gas by-produced in the cathode electrode layer 313A, and migrating water moving from the anode side to the cathode electrode layer 313A pass from the cathode electrode layer 313A through the liquid diffusion layer 313B and are mixed with the cathode fluid CL in the cathode chamber 35.

[0058] Furthermore, the liquid diffusion layer 313B allows the cathode fluid CL, organic hydride, hydrogen gas, and migration water to pass through the liquid diffusion layer 313B, thereby reducing the internal pressure of the cathode chamber 35 when the organic hydride is produced from the cathode fluid CL in the cathode electrode layer 313A. Furthermore, the reduction in the internal pressure of the cathode chamber 35 reduces the load on the cathode pump 243.

[0059] The porosity and volume average pore size of the liquid diffusion layer 313B may be large enough to allow the cathode liquid CL, hydrogen gas, etc. to pass through the liquid diffusion layer 313B.

[0060] The current collector 314 is disposed so as to be in contact with the surface of the anode electrode 312 opposite to the electrolyte membrane 311 side. There are no particular limitations on the structure of the current collector 314 as long as it is electrically conductive, but it is preferable that it does not impede the supply of anode fluid AL to the anode electrode 312 or the flow of anode fluid AL within the anode chamber 34, and it may have a porous structure. The current collector 314 may be elastic and may press the anode electrode 312 against the electrolyte membrane 311 side. The current collector 314 may be attached to the tip of an elastic body such as a spring and pressed firmly against the anode electrode 312.

[0061] The plate member 32 is stacked on the membrane electrode assembly 31 so as to leave a predetermined space between the plate member 32 and the membrane electrode assembly 31. The plate member 32 may be made of, for example, a metal such as stainless steel or titanium, a carbon material, or a corrosion-resistant alloy such as a Cr-Ni-Fe system, a Cr-Ni-Mo-Fe system, a Cr-Mo-Nb-Ni system, or a Cr-Mo-Fe-W-Ni system.

[0062] The plate member 32 includes a pair of plate members 32A and 32B.

[0063] The plate member 32A is connected to a surface of the membrane electrode assembly 31 on the anode electrode 312 side. The plate member 32B is connected to a surface of the cathode electrode 313 on the opposite side to the membrane electrode assembly 31 side. The pair of plate members 32 may be arranged to sandwich the membrane electrode assembly 31 therebetween.

[0064] The plate member 32A may have groove-shaped flow paths on a main surface facing the anode electrode 312. The anolyte AL supplied to the anode chamber 34 may pass through these flow paths to be supplied to the anode electrode 312 and may be discharged from the anode chamber 34 through these flow paths.

[0065] The plate member 32A has a first anode opening 321A and a second anode opening 322A that communicate between the inside and outside of the anode chamber 34.

[0066] The first anode opening 321A is a supply port that supplies the anolyte AL to the anode chamber 34. The first anode opening 321A is preferably provided in the lower part of the anode chamber 34, and may be provided in the bottom surface of the anode chamber 34.

[0067] The second anode opening 322A is an outlet for discharging the anolyte AL from the anode chamber 34. The second anode opening 322A is preferably provided in the upper part of the anode chamber 34, and may be provided on the upper surface of the anode chamber 34.

[0068] The plate member 32B may have groove-shaped flow paths on the main surface facing the cathode electrode 313. The cathode fluid CL supplied to the cathode chamber 35 passes through these flow paths to be supplied to the cathode electrode 313, and is discharged from the cathode chamber 35 through these flow paths.

[0069] The plate member 32B has a first cathode opening 321B and a second cathode opening 322B that communicate between the inside and outside of the cathode chamber 35 .

[0070] The first cathode opening 321B is a supply port that supplies the cathode fluid CL to the cathode chamber 35. The second cathode opening 322B is a discharge port that discharges the cathode fluid CL from the cathode chamber 35. Note that the first cathode opening 321B may be a discharge port that discharges the cathode fluid CL from the cathode chamber 35, and the second cathode opening 322B may be a supply port that supplies the cathode fluid CL to the cathode chamber 35.

[0071] The first cathode opening 321B is preferably provided at the lower part of the cathode chamber 35, and may be provided on the bottom surface of the cathode chamber 35.

[0072] The second cathode opening 322B is preferably provided in the upper part of the cathode chamber 35, and may be provided on the upper surface of the cathode chamber 35.

[0073] When the organic hydride manufacturing apparatus 20A includes only one electrolytic cell 21, the pair of plate members 32 correspond to so-called end plates. When the organic hydride manufacturing apparatus 20A includes multiple electrolytic cells 21 and another electrolytic cell 21 is arranged next to the plate member 32A or the plate member 32B, the plate member 32 corresponds to so-called separators.

[0074] The gasket 33 is a frame-shaped sealing material disposed between the electrolyte membrane 311 and the plate member 32. The gasket 33 is a sealing member that seals the gap between the membrane electrode assembly 31 and the plate member 32. The gasket 33 includes a gasket 33A that seals the gap between the plate member 32A and the membrane electrode assembly 31, and a gasket 33B that seals the gap between the plate member 32B and the membrane electrode assembly 31.

[0075] Although only one electrolytic cell 21 is shown in FIG. 1 , the organic hydride manufacturing apparatus 20A may have a plurality of electrolytic cells 21. In this case, the electrolytic cells 21 are aligned, for example, so that the anode electrodes 312 and the cathode electrode layers 313A are aligned in the same direction, and are stacked with a current-carrying plate sandwiched between adjacent electrolytic cells 21. As a result, the electrolytic cells 21 are electrically connected in series. The current-carrying plate is made of a conductive material such as metal. The electrolytic cells 21 may be connected in parallel, or a combination of series and parallel connections may be used.

[0076] In the electrolytic cell 21, when toluene (TL) is used as an example of the substance to be hydrogenated contained in the cathode fluid CL, the electrode reactions shown in the following formulas (1) and (2) occur. When toluene is used as the substance to be hydrogenated, the resulting organic hydride is methylcyclohexane (MCH). Electrode reaction occurring at the anode electrode 312: 3H ２ O → 3 / 2O ２ +6H ＋ +6e － ...(1) Electrode reaction occurring in the cathode electrode layer 313A: TL+6H ＋ +6e － → MCH ... (2)

[0077] That is, in the anode electrode 312 and the cathode electrode layer 313A, an electrode reaction at the anode electrode 312 and an electrode reaction at the cathode electrode layer 313A proceed in parallel as main reactions. The electrode reaction at the anode electrode 312 electrolyzes water to produce oxygen (O ２ ) gas and protons (H ＋ ) and electrons (e －) is generated. Oxygen gas produced by the electrolysis of water is discharged to the anode pipe 232 via the anode chamber 34. Protons produced by the electrolysis of water pass through the electrolyte membrane 311 together with water molecules and move to the cathode electrode layer 313A. Electrons produced by the electrolysis of water move to the anode output terminal of the power supply unit 22 via the plate member 32A and are supplied from the cathode output terminal of the power supply unit 22 to the cathode electrode layer 313A via the plate member 32B. The protons and electrons supplied to the cathode electrode layer 313A are used to hydrogenate toluene in an electrode reaction at the cathode electrode layer 313A. At the cathode electrode 313, toluene reacts with the electrons supplied from the cathode output terminal of the power supply unit 22 and the protons that have passed through the electrolyte membrane 311 to hydrogenate the toluene, thereby producing methylcyclohexane as an organic hydride.

[0078] In the organic hydride production apparatus 20A, the electrolysis of water and the hydrogenation reaction of toluene, the product to be hydrogenated, can be carried out in one step in the electrolytic cell 21. Therefore, the efficiency of organic hydride production is higher than that of a method of producing organic hydride in a two-step process consisting of a process of producing hydrogen by water electrolysis or the like and a process of chemically hydrogenating the product to be hydrogenated in a reactor such as a plant. Furthermore, the organic hydride production apparatus 20A does not require a reactor for chemical hydrogenation or a high-pressure vessel for storing hydrogen produced by water electrolysis or the like, and therefore can significantly reduce equipment costs.

[0079] In the cathode electrode layer 313A, in addition to the main reaction of hydrogenation of the substance to be hydrogenated, a side reaction occurs to generate hydrogen (H ２ ) A gas evolution reaction may occur. Possible side reactions at the cathode electrode: 2H ＋ +2e － →H ２ ...(3)

[0080] As the supply amount of the substance to be hydrided supplied to the cathode electrode 313 becomes insufficient and the concentration of the substance to be hydrided decreases, the ratio of the substance to the electrode reaction at the cathode electrode 313 increases. Hydrogen gas generated by a side reaction is discharged to the outside via the cathode chamber 35.

[0081] (Power Supply Unit) As shown in FIG. 1 , the power supply unit 22 is a DC power supply that supplies power to the electrolytic cell 21. The power supply unit 22 receives power from the power supply unit 10 and supplies power to the electrolytic cell 21. The anode output terminal of the power supply unit 22 is connected to the anode electrode 312 (anode) of the electrolytic cell 21. The cathode output terminal of the power supply unit 22 is connected to the cathode electrode layer 313A (cathode) of the electrolytic cell 21. As a result, a predetermined electrolysis voltage is applied between the anode electrode 312 and the cathode electrode layer 313A of the electrolytic cell 21, causing an electrolysis current to flow.

[0082] The predetermined voltage applied by the power supply unit 22 can be set as appropriate, preferably between 1.2 V and 2.4 V, for example. By setting the electrode potential of the anode electrode 312 higher than the oxygen generating potential and the electrode potential of the cathode electrode 313 equal to or lower than the standard oxidation-reduction potential of the aromatic compound used as the raw material, an electrochemical reaction is allowed to proceed between the anode electrode 312 and the cathode electrode 313. Therefore, the voltage required to proceed with the electrochemical reaction is the sum of this potential difference and the overvoltage required for the reaction, the overvoltage due to mass transfer and diffusion, and the resistance loss (ohmic loss) caused by the ion transfer resistance of the electrolyte membrane 311 and the contact resistance between the components of the electrolytic cell 21. If the voltage applied by the power supply unit 22 is between 1.2 V and 2.4 V, the electrode reaction can proceed at both electrodes without applying excessive energy. Furthermore, excessive decrease in the potential on the cathode electrode layer 313A side is prevented, thereby suppressing the progression of side reactions other than the hydrogenation of the material to be hydrogenated (e.g., hydrogen gas generation). Furthermore, the potential on the anode electrode 312 side is prevented from becoming too high, and the progress of corrosion of the cathode catalyst used in the anode electrode 312 is suppressed.

[0083] (Anode fluid supply unit) The anode fluid supply unit 23 is a mechanism that circulates the anode fluid AL through the anode chamber 34 and supplies the anode fluid AL to the anode electrode 312, and includes an anode fluid tank 231, an anode pipe 232, and an anode pump 233 that is a drive pump for the anode electrode.

[0084] The anolyte tank 231 stores the anolyte AL to be supplied to the anode chamber 34. The anolyte tank 231 is connected to the anode chamber 34 by an anode pipe 232. The oxygen gas in the anolyte tank 231 may be discharged to the outside by opening an on-off valve V11 provided on a discharge line connected to the anolyte tank 231.

[0085] The anode pipe 232 connects the anolyte tank 231 and the anode chamber 34 of the electrolytic bath 21, and is a circulation path through which the anolyte AL flows between the anolyte tank 231 and the anode chamber 34 of the electrolytic bath 21. The anode pipe 232 has a first anode pipe 232-1 and a second anode pipe 232-2.

[0086] The first anode pipe 232-1 is an outgoing path for supplying the anode fluid AL from the anode fluid tank 231 to the anode chamber 34, and connects the anode fluid tank 231 to the anode chamber 34. One end of the first anode pipe 232-1 is connected to the anode fluid tank 231, and the other end of the first anode pipe 232-1 is connected to the first anode opening 321A of the anode chamber 34.

[0087] The second anode pipe 232-2 is a return path for recovering the anode fluid from the anode chamber 34 to the anode fluid tank 231, and connects the anode chamber 34 to the anode fluid tank 231. One end of the second anode pipe 232-2 is connected to the anode fluid tank 231, and the other end of the second anode pipe 232-2 is connected to the second anode opening 322A of the anode chamber 34.

[0088] The anode pump 233 is provided on the first anode pipe 232-1. The anolyte tank 231 is connected to the anode chamber 34 by the first anode pipe 232-1. The anolyte tank 231 is also connected to the anode chamber 34 by the second anode pipe 232-2.

[0089] The anode pump 233 can be configured, for example, by various pumps such as a gear pump or a cylinder pump, or a gravity flow device, etc. The anode fluid supply unit 23 may circulate the anode fluid AL using a fluid delivery device other than a pump.

[0090] The anolyte AL stored in the anolyte tank 231 flows through the anode pipe 232 by the drive of the anode pump 233, and circulates between the anolyte tank 231 and the anode chamber 34. The anolyte AL in the anolyte tank 231 passes through the first anode pipe 232-1, flows into the anode chamber 34 from the first anode opening 321A of the electrolytic cell 21, and is supplied to the anode electrode 312. The anolyte AL that has flowed into the anode electrode 312 is subjected to an electrode reaction at the anode electrode 312. The anolyte AL in the anode electrode 312 passes through the second anode opening 322A of the electrolytic cell 21 and the second anode pipe 232-2, and is returned to the anolyte tank 231, where it is stored.

[0091] The anolyte tank 231 may function as a gas-liquid separator. At the anode electrode 312, oxygen gas is generated by electrolysis of water, and therefore the anolyte AL discharged from the anode chamber 34 contains oxygen gas and dissolved oxygen. The oxygen gas is separated from the anolyte AL in the anolyte tank 231 and removed to the outside of the system. The anolyte AL from which the oxygen gas has been separated passes through the first anode piping 232-1 and is supplied again to the electrolytic cell 21.

[0092] An unillustrated gas-liquid separator may be provided midway along the second anode pipe 232-2. A commonly used, well-known gas-liquid separator may be used as the gas-liquid separator. The unillustrated gas-liquid separator may separate oxygen gas generated by electrolysis of water at the anode electrode 312 from the anolyte AL and discharge the oxygen gas to the outside of the system.

[0093] Furthermore, the anode fluid supply unit 23 circulates the anode fluid AL between the anode electrode 312 and the anode fluid tank 231, but the anode fluid AL may be sent from the anode electrode 312 to the outside of the system without being returned to the anode fluid tank 231.

[0094] (Cathode fluid supply unit) The cathode fluid supply unit 24 is a mechanism that circulates the cathode fluid CL in the cathode chamber 35 and supplies the cathode fluid CL to the cathode electrode 313, and includes a cathode fluid tank 241, a cathode pipe 242, a cathode pump 243 that is a drive pump for the cathode electrode, and a branch discharge pipe 245.

[0095] The cathode fluid tank 241 stores the cathode fluid CL. The cathode fluid tank 241 is connected to the cathode chamber 35 by a cathode pipe 242. When the cathode fluid CL contains an organic hydride produced at the cathode electrode 313, the cathode fluid tank 241 stores not only the material to be hydrided but also the organic hydride produced at the cathode electrode 313.

[0096] The cathode fluid tank 241 also functions as a gas-liquid separator and an oil-water separator, and separates hydrogen gas and transition water from the cathode fluid CL discharged from the electrolytic cell 21. The methods for gas-liquid separation and oil-water separation are not particularly limited, and methods similar to those commonly used for gas-liquid separation and oil-water separation can be used. For example, methods similar to those used for gas-liquid separation and oil-water separation in commonly used known gas-liquid separators and oil-water separators can be used.

[0097] Because hydrogen gas is generated by a side reaction at the cathode electrode 313, the cathode fluid CL recovered from the cathode chamber 35 contains hydrogen gas and dissolved hydrogen. The hydrogen gas is separated from the cathode fluid CL in the cathode fluid tank 241 and removed from the system. A gas exhaust line is connected to the cathode fluid tank 241, and the hydrogen gas is discharged to the outside by opening an on-off valve V21 provided on the gas exhaust line.

[0098] The migrated water in the catholyte tank 241 can be separated at the interface formed between the catholyte tank 241 and the catholyte CL. The migrated water separated at the interface from the catholyte CL in the catholyte tank 241 is taken out to a branched discharge pipe 245.

[0099] The catholyte CL from which the hydrogen gas and the transition water have been separated is supplied again to the electrolytic cell 21 .

[0100] The cathode pipe 242 is a circulation path through which the cathode fluid CL flows between the cathode fluid tank 241 and the cathode chamber 35 of the electrolytic cell 21. The cathode pipe 242 has a first cathode pipe 242-1 and a second cathode pipe 242-2.

[0101] The first cathode piping 242-1 is an outward path for supplying the cathode fluid CL from the cathode fluid tank 241 to the cathode chamber 35, and connects the cathode fluid tank 241 to the cathode chamber 35. One end of the first cathode piping 242-1 is connected to the cathode fluid tank 241, and the other end of the first cathode piping 242-1 is connected to the first cathode opening 321B of the cathode chamber 35.

[0102] The second cathode pipe 242-2 is a return path for supplying the cathode fluid CL from the cathode chamber 35 to the cathode fluid tank 241, and connects the cathode chamber 35 with the cathode fluid tank 241. One end of the second cathode pipe 242-2 is connected to the second cathode opening 322B of the cathode chamber 35, and the other end of the second cathode pipe 242-2 is connected to the cathode fluid tank 241.

[0103] The cathode pump 243 is provided midway along the first cathode pipe 242-1. The cathode pump 243 can be configured with a known pump such as a gear pump or a cylinder pump, similar to the anode pump 233. Note that the cathode fluid supply unit 24 may circulate the cathode fluid CL using a fluid delivery device other than a pump.

[0104] The branch discharge pipe 245 is provided in the cathode fluid tank 241 and is a flow path for separating migration water in the cathode fluid CL from the cathode fluid CL and discharging it to the outside of the system. Because water moves as migration water from the anode 312 together with protons to the cathode electrode layer 313A, migration water is mixed into the cathode fluid CL discharged from the cathode chamber 35. The branch discharge pipe 245 discharges migration water in the cathode fluid CL supplied to the cathode fluid tank 241 to the outside of the cathode fluid tank 241 and supplies it to the aeration unit 25A. An on-off valve V22 is provided in the branch discharge pipe 245, and by opening the on-off valve V22, migration water in the cathode fluid CL is discharged from the cathode fluid tank 241 and supplied to the aeration unit 25A.

[0105] The cathode fluid CL stored in the cathode fluid tank 241 flows through the cathode piping 242 by driving the cathode pump 243, and circulates between the cathode fluid tank 241 and the cathode chamber 35. The cathode fluid CL stored in the cathode fluid tank 241 passes through the first cathode piping 242-1, flows into the cathode chamber 35 from the first cathode opening 321B of the electrolytic cell 21, and is supplied to the cathode electrode layer 313A. The cathode fluid CL that has flowed into the cathode electrode layer 313A is used for an electrode reaction in the cathode electrode layer 313A. The cathode fluid CL in the cathode electrode layer 313A flows into the cathode fluid tank 241 from the second cathode opening 322B of the electrolytic cell 21 via the second cathode piping 242-2.

[0106] The cathode fluid CL discharged from the cathode electrode layer 313A contains hydrogen gas generated by a side reaction in the cathode electrode layer 313A and migrated water that has migrated with protons from the anode electrode 312. In the cathode fluid tank 241, the hydrogen gas in the cathode fluid CL is separated from the cathode fluid CL and discharged to the outside of the system, and the migrated water in the cathode fluid CL is separated from the cathode fluid CL and discharged to the branch discharge pipe 245.

[0107] The cathode fluid CL from which the hydrogen gas and the transition water have been separated is supplied again to the electrolytic cell 21 through the first cathode pipe 242-1.

[0108] The cathode fluid supply unit 24 circulates the cathode fluid CL between the cathode electrode layer 313A and the cathode fluid tank 241, but is not limited to this configuration. The cathode fluid CL may be sent from the cathode electrode layer 313A to outside the system without being returned to the cathode fluid tank 241.

[0109] Furthermore, in the cathode liquid supply unit 24, the cathode liquid tank 241 functions as a gas-liquid separation unit and an oil-water separation unit, but is not limited to this configuration, and a gas-liquid separation unit and an oil-water separation unit for separating the hydrogen gas and migration water in the cathode liquid CL discharged from the electrolytic cell 21 from the cathode liquid CL may be provided separately from the cathode liquid tank 241.

[0110] (Aeration Section) The aeration section 25A is separated from the cathode liquid tank 241 and supplies aeration gas to the transition water supplied through the branch discharge pipe 245 to separate at least a portion of the organic matter dissolved in the transition water and reduce the amount of organic matter dissolved in the transition water. The aeration section 25A has an aeration tank 251, an air supply line L11, a circulation line L12, and a dissolved substance removal line L13.

[0111] The aeration gas is a gas containing at least one of oxygen and nitrogen, and may be any gas that can move organic matter dissolved in the transferred water, and it is preferable to use, for example, air, oxygen gas, nitrogen gas, etc. In this embodiment, air is used as the aeration gas, but nitrogen gas may be used instead of air.

[0112] Examples of organic substances dissolved in the transferred water include the substances to be hydrided contained in the catholyte CL and organic hydrides produced at the cathode electrode 313. At least one of these may be contained.

[0113] The aeration tank 251 is connected to the branch discharge pipe 245 and stores the transition water separated in the cathode liquid tank 241 and containing dissolved organic matter. The aeration tank 251 aerates the stored transition water by supplying air, supplied via the air supply line L11, as aeration gas. Aerating the transition water with air causes the dissolved organic matter to migrate from the transition water to the gaseous air and separate from the transition water, thereby reducing the concentration of dissolved organic matter in the transition water. Specifically, when air is blown into the transition water containing dissolved organic matter, the air immediately after blowing contains no organic matter. Therefore, the dissolved organic matter migrates to the gas-liquid interface between the transition water and the air, and from that gas-liquid interface to the air. The air containing the organic matter then migrates from the transition water to the upper space within the aeration tank 251. As a result, the organic matter dissolved in the transition water separates from the transition water and migrates into the air, thereby reducing the concentration of dissolved organic matter in the transition water. Therefore, the aeration tank 251 aerates the transition water containing dissolved organic matter, thereby obtaining aerated transition water, which is transition water in which the concentration of dissolved organic matter has been reduced.

[0114] Furthermore, the aeration tank 251 may separate from the transition water trace amounts of hydrogen that may be contained in the transition water, in addition to the organic matter dissolved in the transition water. That is, the transition water separated in the cathode fluid tank 241 may contain trace amounts of hydrogen that are not completely separated in the cathode fluid tank 241. In the aeration tank 251, by aerating the transition water with air, trace amounts of hydrogen may also be transferred from the transition water to the gas phase air, in addition to the dissolved organic matter, and contained in the gas phase. Furthermore, in the aeration tank 251, by aerating the transition water with air, a portion of the transition water may also be transferred as water vapor to the gas phase, and contained in the gas phase. That is, in the aeration tank 251, hydrogen and water vapor may be contained in the gas phase in addition to the organic matter.

[0115] In the aeration tank 251, the concentration of organic matter dissolved in the transferred water is preferably reduced to 1 / 5 or less of the concentration before being supplied to the aeration tank 251, more preferably 1 / 10 or less, and even more preferably 1 / 50 or less.

[0116] The aeration tank 251 preferably reduces the concentration of organic matter dissolved in the transferred water to a predetermined value or less.

[0117] The predetermined value may be determined as appropriate depending on the purity of water required for the anode fluid AL, such as suppressing deterioration of the anode electrode 312, and is, for example, preferably 100 ppm or less, more preferably 50 ppm or less, and even more preferably 10 ppm or less.

[0118] The air supply line L11 is connected to the aeration tank 251 and supplies air as an aeration gas to the aeration tank 251. The air sent to the air supply line L11 may be taken in directly from outside or may be taken in from an air storage tank that stores air to be used for aeration. An on-off valve V31 is provided in the air supply line L11, and the amount of air supplied from the air supply line L11 to the aeration tank 251 is adjusted by the on-off valve V31.

[0119] The circulation line L12 connects the aeration tank 251 and the anode fluid tank 231, and supplies the aeration-treated transfer water discharged from the aeration tank 251 from the aeration tank 251 to the anode fluid supply unit 23.

[0120] Although the circulation line L12 is connected to the anolyte tank 231, it may be connected to any other location as long as it can be mixed with the anolyte AL, for example, the first anode pipe 232-1 or the second anode pipe 232-2.

[0121] The dissolved substance removal line L13 is connected to the aeration tank 251 and discharges to the outside the organic matter and air separated from the migration water in the aeration tank 251. The organic matter discharged to the outside may be sent to, for example, an external exhaust gas treatment facility for treatment.

[0122] Furthermore, aeration unit 25A may have a gas treatment facility in circulation line L12 that removes gases contained in the aeration treatment transfer water. Furthermore, aeration unit 25A may have a water purification tank in circulation line L12 that purifies the aeration treatment transfer water. If bacteria or other microorganisms are contained in the air used as the aeration gas, these bacteria may grow in electrolytic cell 21 and cathode liquid supply unit 24 if supplied to cathode chamber 35 of electrolytic cell 21 together with the aeration treatment transfer water. Therefore, it is preferable to remove bacteria and other microorganisms contained in the aeration treatment transfer water in a water purification tank.

[0123] (Measurement Unit) The measurement unit 26 has a voltage measurement unit 26A, a current measurement unit 26B, an organic substance concentration measurement unit 26C, and an ionically conductive substance concentration measurement unit 26D, and a signal indicating the detection result measured by the measurement unit 26 is input to the control unit 27.

[0124] Voltage measurement unit 26A measures at least one of a signal indicating the voltage of electrolytic bath 21, a signal indicating the potential of anode electrode 312, and a signal indicating the potential of cathode electrode 313. Voltage measurement unit 26A only needs to be able to measure the potential of each electrode and the voltage of electrolytic bath 21, and a commonly used voltmeter may be used as voltage measurement unit 26A, for example. Voltage measurement unit 26A transmits a signal indicating the measured voltage to control unit 27.

[0125] When the voltage measurement unit 26A detects the voltage of the electrolytic cell 21, one terminal of the voltage measurement unit 26A is connected to the anode electrode 312 and the other terminal is connected to the cathode electrode 313, and the voltage, which is the potential difference between the two electrodes, is detected. When the voltage measurement unit 26A detects the potential of the anode electrode 312 or the cathode electrode 313, a reference electrode is provided on the electrolyte membrane 311. The reference electrode is maintained at a reference electrode potential. For example, a reversible hydrogen electrode (RHE) is used as the reference electrode. The reference electrode is connected to one terminal of the voltage measurement unit 26A, and the anode electrode 312 or the cathode electrode 313 to be detected is connected to the other terminal, and the potential of the electrode relative to the reference electrode is detected. The voltage measurement unit 26A transmits a signal indicating the measured potential to the control unit 27.

[0126] Current measuring unit 26B is provided in electrolytic bath 21 and measures the current flowing between anode electrode 312 and cathode electrode 313. Current measuring unit 26B only needs to be able to measure the current flowing between anode electrode 312 and cathode electrode 313, and a commonly used ammeter may be used as current measuring unit 26B, for example. Current measuring unit 26B transmits a signal indicating the measured current value to control unit 27.

[0127] The organic substance concentration measuring unit 26C is provided in the circulation line L12 and measures the concentration of organic substances dissolved in the transferred water. The organic substance concentration measuring unit 26C is only required to be able to measure the concentration of organic substances dissolved in the transferred water, and a commonly used concentration meter or the like may be used as the organic substance concentration measuring unit 26C. The organic substance concentration measuring unit 26C may also be provided in the cathode pipe 242. The organic substance concentration measuring unit 26C transmits a signal indicating the concentration of organic substances to the control unit 27.

[0128] The ion-conductive substance concentration measuring unit 26D may be provided in the anode pipe 232, and may be provided between the anode pump 233 of the first anode pipe 232-1 and the first anode opening 321A. The ion-conductive substance concentration measuring unit 26D measures the concentration of the ion-conductive substance in the anolyte AL. Examples of the ion-conductive substance include protons (H ＋The ion conductive substance concentration measuring unit 26D may be any unit as long as it can measure the concentration of the ion conductive substance, and a known ion concentration sensor may be used as the ion conductive substance concentration measuring unit 26D. The ion conductive substance concentration measuring unit 26D transmits a signal indicating the measured concentration of the ion conductive substance to the control unit 27.

[0129] (Control Unit) The control unit 27 is electrically connected to each of the components constituting the organic hydride manufacturing apparatus 20A, such as the electrolytic cell 21, the power supply unit 22, the anolyte supply unit 23, the catholyte supply unit 24, the aeration unit 25A, and the measurement unit 26, so as to be able to control these components, and controls the operation of the organic hydride manufacturing apparatus 20A. The control unit 27 has a memory means for storing a control program and various types of memory information, and a calculation means that operates based on the control program. The control unit 27 is realized by the calculation means reading and executing the control program, etc., stored in the memory means.

[0130] The control unit 27 controls the power supplied from the power supply unit 22 to the electrolytic cell 21 to control the potentials of the anode electrode 312 and the cathode electrode 313 .

[0131] Furthermore, the control unit 27 may store information on the current-voltage characteristics (IV characteristics) of the electrolytic cell 21 in advance in a storage device included in the control unit 27. When the control unit 27 stores information on the IV characteristics, this information may be freely updateable. The IV characteristics of the electrolytic cell 21 are determined depending on the catalyst composition of each electrode, the type of liquid diffusion layer 313B and substrate, the type of electrolyte membrane 311, the flow path structure of the anode fluid AL and cathode fluid CL in the electrolytic cell 21, the dimensions of each component, and the like, and are preferably measured and understood in advance. In this case, the control unit 27 receives a signal indicating the amount of power supplied from the power supply unit 10, thereby determining the amount of power that can be supplied from the power supply unit 22 to the electrolytic cell 21. The control unit 27 can control the value of the current flowing through the electrolytic cell 21 by calculating the voltage to be applied to the electrolytic cell 21 from the IV characteristics.

[0132] The control unit 27 is electrically connected to the measurement unit 26 so as to receive a signal indicating the detection result of the measurement unit 26. The control unit 27 may control the output of the power supply unit 22 to control the potentials of the anode electrode 312 and the cathode electrode 313, or may control the currents flowing through the anode electrode 312 and the cathode electrode 313, based on the measurement results of the voltage measurement unit 26A, the current measurement unit 26B, and the ionically conductive material concentration measurement unit 26D of the measurement unit 26. The control unit 27 may control the anolyte supply unit 23 and the catholyte supply unit 24. Specifically, the control unit 27 may control the driving of the anode pump 233 and the cathode pump 243, the discharge of oxygen from the anolyte tank 231, the discharge of hydrogen from the catholyte tank 241, the discharge of transition water from the branch discharge pipe 245, the opening and closing of the on-off valves V11, V21, and V22, etc. The control unit 27 may control the voltage conversion in the power conversion unit 13 depending on the operating status of the first power supply unit 11, the amount of power output, and the like.

[0133] The control unit 27 may control the aeration tank 251 and the on-off valve V31 based on the measurement results of the organic matter concentration measurement unit 26C of the measurement unit 26 to adjust the rate of reduction of the concentration of dissolved organic matter contained in the transfer water discharged from the cathode liquid tank 241.

[0134] The operation of the organic hydride manufacturing apparatus 20A will be described. In the organic hydride manufacturing apparatus 20A, the anode pump 233 and the cathode pump 243 are driven to cause the anolyte AL and the cathode solution CL to flow from the anolyte tank 231 and the cathode solution tank 241 to the electrolytic cell 21. The anolyte AL passes through the anode chamber 34 of the electrolytic cell 21 and is supplied to the anode electrode 312, and the cathode solution CL passes through the cathode chamber 35 of the electrolytic cell 21 and is supplied to the cathode electrode 313.

[0135] When power is supplied from the power supply unit 10 to the power supply unit 22, the power supply unit 22 sends the power supplied from the power supply unit 10 to the electrolytic cell 21. When power is supplied from the power supply unit 22 to the electrolytic cell 21, a predetermined electrolysis voltage is applied between the anode electrode 312 and the cathode electrode layer 313A of the electrolytic cell 21, causing an electrolytic current to flow. As a result of the current flowing between the anode electrode 312 and the cathode electrode layer 313A, the electrode reactions represented by the above formulas (1) and (2) proceed in parallel in the electrolytic cell 21, causing the electrolysis of water and the hydrogenation reaction of the substance to be hydrogenated to occur simultaneously. As a result of these electrode reactions, an anolyte AL containing oxygen gas is discharged from the anode chamber 34 to the anode piping 232, and a catholyte CL containing an organic hydride is discharged from the cathode chamber 35 to the cathode piping 242.

[0136] The anolyte AL discharged to the anode pipe 232 is supplied to the anolyte tank 231 and stored in the anolyte tank 231. The oxygen gas contained in the anolyte AL is discharged to the outside by opening an on-off valve V11 provided in a discharge line connected to the anolyte tank 231.

[0137] The cathode fluid CL discharged to the cathode pipe 242 is supplied to the cathode fluid tank 241, where it is separated from the hydrogen gas and transition water contained in the cathode fluid CL and stored inside. The hydrogen gas separated from the cathode fluid CL is discharged to the outside by opening an on-off valve V21 provided in a discharge line connected to the cathode fluid tank 241.

[0138] The transition water separated from the cathode fluid CL is supplied to the aeration tank 251 through the branch discharge pipe 245 by opening the on-off valve V22 provided in the branch discharge pipe 245.

[0139] Air is supplied to the aeration tank 251 from the outside as an aeration gas via the air supply line L11, and at least a portion of the organic matter dissolved in the transfer water discharged from the cathode liquid tank 241 is separated, reducing the amount of dissolved organic matter, thereby obtaining aerated transfer water with a reduced concentration of dissolved organic matter (aeration process).

[0140] The aeration treatment transfer water discharged from the aeration tank 251 passes through the circulation line L12 and is supplied to the anolyte tank 231 (circulation process).

[0141] The aeration treatment transition water is returned to the anolyte AL and is reused as the anolyte AL.

[0142] 1, the organic hydride production system 1A can generate hydrogen by recovering the organic hydride produced in the organic hydride production apparatus 20A in the cathode solution CL and desorbing hydrogen from the organic hydride. The generated hydrogen is supplied to, for example, a hydrogen station, a fuel cell, a hydrogen power generation apparatus, etc.

[0143] The substance to be hydrogenated, such as toluene, which is produced by desorbing hydrogen from the organic hydride, may be recovered by a known process such as distillation separation, extraction separation, membrane separation, or adsorption separation, and stored in a storage tank, or may be used as a gasoline base material, a raw material for chemical products, etc. The substance to be hydrogenated stored in the storage tank may be reused.

[0144] As described above, the organic hydride manufacturing apparatus 20A includes the electrolytic cell 21, the anode fluid supply unit 23, the cathode fluid supply unit 24, and the aeration unit 25A. The aeration unit 25A supplies an aeration gas to the transition water discharged from the cathode fluid tank 241, thereby enabling the aeration unit 25A to accurately separate at least a portion of the organic matter dissolved in the transition water discharged together with the cathode fluid CL from the electrolytic cell 21. Thus, the organic hydride manufacturing apparatus 20A can reduce the concentration of organic matter dissolved in the transition water contained in the cathode fluid CL discharged from the electrolytic cell 21.

[0145] Methods for separating organic matter contained in the transition water include, for example, separation using filters such as activated carbon filters, ceramic membrane filters, and PTFE hollow fiber membrane modules; separation by distillation based on the boiling point difference by cooling or heating the transition water; and separation using a coalescer. Among these, the aforementioned filter and coalescer separation methods can only separate organic matter that separates from the transition water to form an interface, and cannot separate dissolved organic matter. With distillation separation methods, it is difficult to accurately separate dissolved organic matter when the boiling points of the transition water and the organic matter are close. On the other hand, the organic hydride production apparatus 20A can remove organic matter dissolved in the transition water and sufficiently reduce the concentration of organic matter in the transition water by aerating the transition water using air as an aeration gas in the aeration section 25A.

[0146] Furthermore, the aeration unit 25A can return the aeration-treated transition water, in which the concentration of dissolved organic matter has been reduced, to the anode fluid tank 231. Because the concentration of dissolved organic matter in the aeration-treated transition water is sufficiently reduced compared to before it was supplied to the aeration unit 25A, even if the aeration-treated transition water discharged from the aeration unit 25A is supplied to the anode fluid tank 231 and mixed with the anode fluid AL in the anode fluid tank 231 to be used as the anode fluid AL, deterioration of the anode catalyst of the anode electrode 312 due to organic matter dissolved in the aeration treatment mechanism water can be suppressed. Therefore, the organic hydride production apparatus 20A can effectively use the transition water generated by the electrode reaction in the electrolytic cell 21 as the anode fluid AL. Therefore, the organic hydride production apparatus 20A can stably cause the electrode reaction at the anode electrode 312 while reusing the aeration-treated transition water as the anode fluid AL.

[0147] In the organic hydride manufacturing apparatus 20A, it is preferable that the aeration section 25A uses air as the aeration gas. Since outside air can be used as the air, the aeration section 25A can easily prepare the aeration gas, which makes it easier to separate organic matter dissolved in the transition water.

[0148] In the organic hydride manufacturing apparatus 20A, the aeration section 25A preferably has an air supply line L11. This allows the aeration section 25A to easily supply air from the outside air as an aeration gas to the aeration tank 251 via the air supply line L11, making it easier to separate organic matter dissolved in the transferred water.

[0149] In the organic hydride manufacturing apparatus 20A, the aeration unit 25A preferably reduces the concentration of organic matter dissolved in the transition water in the aeration tank 251 to a predetermined value or less. This allows the aeration unit 25A to more reliably prevent the anode electrode 312 from being deteriorated by the organic matter, even when the transition water is returned to the anode fluid supply unit 23 and used as the anode fluid AL. Therefore, the organic hydride manufacturing apparatus 20A can return the transition water generated by the electrode reaction in the electrolytic bath 21 to the anolyte tank 231 in a state in which it can be reused as the anode fluid AL. Therefore, the organic hydride manufacturing apparatus 20A can more reliably prevent the anode electrode 312 from being deteriorated by the organic matter, and can stably cause the electrode reaction at the anode electrode 312, while using the transition water generated by the electrode reaction in the electrolytic bath 21 as the anode fluid AL.

[0150] The organic hydride manufacturing apparatus 20A preferably has a cathode liquid supply unit 24. This allows the organic hydride manufacturing apparatus 20A to supply the cathode electrode 313 with the cathode liquid CL, and to separate migration water from the cathode liquid CL discharged from the aeration unit 25A and supply it to the cathode chamber 35. The organic hydride manufacturing apparatus 20A can circulate the cathode liquid CL between the cathode chamber 35 and the cathode liquid tank 241, keeping it in a usable state.

[0151] In the organic hydride manufacturing apparatus 20A, the cathode fluid supply unit 24 preferably has a cathode fluid tank 241 and cathode piping 242, and separates the organic matter and hydrogen gas in the cathode fluid CL in the cathode fluid tank 241. Because the cathode fluid supply unit 24 can separate the organic matter and hydrogen gas from the cathode fluid CL in the cathode fluid tank 241, the organic hydride manufacturing apparatus 20A can recover transition water containing dissolved organic matter while having a simple configuration.

[0152] In the organic hydride production apparatus 20A, the aeration unit 25A preferably includes an aeration tank 251 and a circulation line L12. The aeration unit 25A supplies an aeration gas to the transition water discharged from the cathode fluid tank 241 in the aeration tank 251, thereby accurately separating organic matter dissolved in the transition water discharged together with the cathode fluid CL from the electrolytic cell 21. This reduces the concentration of organic matter dissolved in the transition water contained in the cathode fluid CL discharged from the electrolytic cell 21. The aeration unit 25A can also supply aeration-treated transition water, the concentration of which has been reduced in the aeration tank 251, to the anode fluid tank 231 via the circulation line L12. Even when the aeration-treated transition water is mixed with the anode fluid AL in the anode fluid tank 231, deterioration of the anode catalyst of the anode electrode 312 due to organic matter dissolved in the aeration treatment mechanism water can be suppressed. Therefore, the organic hydride manufacturing apparatus 20A can effectively utilize, as the anolyte AL, the transition water generated by the electrode reaction in the electrolytic cell 21. Therefore, the organic hydride manufacturing apparatus 20A can stably cause the electrode reaction at the anode electrode 312 while reusing the aerated transition water as the anolyte AL.

[0153] The organic hydride production apparatus 20A preferably includes an organic matter concentration measurement unit 26C in the circulation line L12. This allows the organic matter concentration in the aeration treatment transition water discharged from the aeration tank 251 to be measured, making it possible to appropriately determine whether deterioration of the anode electrode 312 will occur when the transition water generated by the electrode reaction in the electrolytic tank 21 is used as the anode fluid AL. Therefore, based on the measurement results from the organic matter concentration measurement unit 26C, the organic hydride production apparatus 20A can stably cause the electrode reaction at the anode electrode 312 while effectively utilizing the aeration treatment transition water as the anode fluid AL.

[0154] The organic hydride manufacturing apparatus 20A may contain at least one of a material to be hydrided and an organic hydride as the organic substance dissolved in the transfer water. The organic hydride manufacturing apparatus 20A can appropriately reduce the concentrations of the organic substance dissolved in the transfer water, whether it is the material to be hydrided contained in the cathode fluid CL or the organic hydride produced in the electrolytic bath 21. Therefore, regardless of the type of material to be hydrided or the organic hydride dissolved as the organic substance in the transfer water, the organic hydride manufacturing apparatus 20A can stably cause an electrode reaction at the anode electrode 312 while reusing the transfer water generated by the electrode reaction in the electrolytic bath 21 as the anolyte fluid AL.

[0155] The organic hydride production system 1A can include a power supply unit 10 and the above-described organic hydride production apparatus 20A. As a result, the organic hydride production system 1A can produce organic hydride in the organic hydride production apparatus 20A using power supplied from the power supply unit 10.

[0156] In the organic hydride production system 1A, the power supply unit 10 preferably includes at least one of a first power supply unit 11 and a second power supply unit 12. This allows the organic hydride production system 1A to stably operate the organic hydride production apparatus 20A by supplying at least one of the renewable energy-derived power supplied from the first power supply unit 11 and the power generated by the second power supply unit 12 to the electrolytic cell 21. In addition, the organic hydride production system 1A produces organic hydride in the organic hydride production apparatus 20A using the renewable energy-derived power supplied from the first power supply unit 11, thereby reducing the consumption of fossil fuels involved in hydrogen production and reducing CO ２Furthermore, by supplying the electric power generated by the second power supply unit 12 to the electrolytic cell 21, the organic hydride production system 1A can stably operate the organic hydride production apparatus 20A even when the electric power supplied from the first power supply unit 11 to the electrolytic cell 21 of the organic hydride production apparatus 20A is insufficient. This allows the organic hydride production system 1A to stably produce organic hydride in the organic hydride production apparatus 20A.

[0157] In the organic hydride manufacturing system 1A, the power supply unit 10 preferably includes a first power supply unit 11 and a second power supply unit 12. This allows the organic hydride manufacturing system 1A to more stably produce organic hydride in the organic hydride manufacturing apparatus 20A.

[0158] In this embodiment, the organic hydride manufacturing apparatus 20A controls the operation of the organic hydride manufacturing apparatus 20A, such as controlling the power supplied from the power supply unit 22 to the electrolytic cell 21 and controlling the amount of air supplied to the aeration tank 251, using the control unit 27 based on the measurement results of the measurement unit 26, but the operation of the organic hydride manufacturing apparatus 20A may also be controlled appropriately and as needed by an operator or the like.

[0159] Second Embodiment An organic hydride production system including an organic hydride production apparatus according to a second embodiment of the present invention (hereinafter simply referred to as "this embodiment") will be described. The organic hydride production system according to the second embodiment is the same as the organic hydride production system 1A according to the first embodiment shown in Fig. 1 , except that oxygen gas produced when water in the anolyte AL is oxidized by the anode electrode 312 is used as the aeration gas to be supplied to the aeration tank 251, instead of air.

[0160] Fig. 3 is a schematic diagram showing the overall configuration of an organic hydride production system including an organic hydride production apparatus according to the second embodiment. As shown in Fig. 3, an aeration unit 25B included in an organic hydride production apparatus 20B of an organic hydride production system 1B according to the second embodiment has an oxygen gas supply line L21 instead of the air supply line L11 of the aeration unit 25A of the organic hydride production system 1A according to the first embodiment shown in Fig. 1. Note that the organic hydride production system 1B is the same as the organic hydride production system 1A according to the first embodiment shown in Fig. 1 except that the air supply line L11 included in the aeration unit 25A is replaced with an oxygen gas supply line L21, and therefore only the configuration of the oxygen gas supply line L21 will be described.

[0161] The oxygen gas supply line L21 connects the anolyte tank 231 and the aeration tank 251, and is a line for supplying oxygen gas generated when the water of the anolyte AL is oxidized by the anode electrode 312 to the aeration tank 251 as an aeration gas.

[0162] An on-off valve V41 is provided on the oxygen gas supply line L21, and the amount of oxygen gas supplied from the oxygen gas supply line L21 to the aeration tank 251 is adjusted by the on-off valve V41. The oxygen gas contained in the anolyte AL discharged from the electrolytic cell 21 and supplied to the anolyte tank 231 is supplied to the aeration tank 251 from the anolyte tank 231 through the oxygen gas supply line L21 by opening the on-off valve V41 provided on the oxygen gas supply line L21.

[0163] The control unit 27 may control the aeration tank 251 and the on-off valve V41 based on the measurement results of the organic matter concentration measurement unit 26C of the measurement unit 26, etc., to adjust the rate of reduction in the concentration of dissolved organic matter contained in the transfer water discharged from the cathode liquid tank 241.

[0164] In the organic hydride production apparatus 20B, transition water separated from the cathode fluid CL in the cathode fluid tank 241 is supplied to the aeration tank 251. Thereafter, oxygen gas separated from the anolyte AL in the anolyte tank 231 is supplied as an aeration gas to the aeration tank 251 via the oxygen gas supply line L21. In this manner, the aeration unit 25B separates organic matter dissolved in the transition water discharged from the cathode fluid tank 241 from the transition water, thereby reducing the concentration of the organic matter dissolved in the transition water. As a result, aerated transition water with a reduced concentration of dissolved organic matter is obtained.

[0165] The organic hydride production apparatus 20B includes an aeration unit 25B having an oxygen gas supply line L21. The aeration unit 25B aerates the transition water discharged from the cathode fluid tank 241 in the aeration tank 251 by supplying oxygen gas separated from the anolyte AL in the anolyte tank 231 as an aeration gas. This allows the aeration unit 25B to effectively use the oxygen gas to separate organic matter dissolved in the transition water contained in the cathode fluid CL discharged from the electrolytic cell 21, while separating and reducing the organic matter dissolved in the transition water. Therefore, the organic hydride production apparatus 20B can efficiently reduce the concentration of organic matter dissolved in the transition water.

[0166] Third Embodiment An organic hydride production system including an organic hydride production apparatus according to a third embodiment of the present invention (hereinafter simply referred to as "the present embodiment") will be described. The organic hydride production system according to the third embodiment is the same as the organic hydride production system 1B according to the second embodiment shown in FIG. 3 , except that nitrogen gas is further used as the aeration gas supplied to the aeration tank 251.

[0167] Fig. 4 is a schematic diagram showing the overall configuration of an organic hydride production system including an organic hydride production apparatus according to the third embodiment. As shown in Fig. 4, an aeration section 25C included in an organic hydride production apparatus 20C of an organic hydride production system 1C according to the third embodiment further includes a nitrogen gas supply section 41 in addition to the aeration section 25B of the organic hydride production system 1B according to the second embodiment shown in Fig. 3. Note that the organic hydride production system 1C is similar to the organic hydride production system 1B according to the second embodiment shown in Fig. 3 except that the nitrogen gas supply section 41 is added to the aeration section 25B, and therefore only the configuration of the nitrogen gas supply section 41 will be described.

[0168] The nitrogen gas supply unit 41 supplies nitrogen gas as an aeration gas to the aeration tank 251, and has a nitrogen gas storage unit 411 and a nitrogen gas supply line L31.

[0169] The nitrogen gas storage unit 411 stores nitrogen gas to be supplied as an aeration gas to the aeration tank 251. The nitrogen gas storage unit 411 may be a storage tank in which nitrogen gas is stored.

[0170] The nitrogen gas supply line L31 connects the nitrogen gas storage section 411 and the aeration tank 251, and is a line that supplies nitrogen gas to the aeration tank 251 as an aeration gas.

[0171] An on-off valve V51 is provided on the nitrogen gas supply line L31, and the amount of nitrogen gas supplied from the nitrogen gas supply line L31 to the aeration tank 251 is adjusted by the on-off valve V51. The nitrogen gas in the nitrogen gas supply unit 41 is supplied to the aeration tank 251 through the nitrogen gas supply line L31 by opening the on-off valve V51 provided on the nitrogen gas supply line L31.

[0172] The control unit 27 may control the aeration tank 251 and the on-off valves V41 and V51 based on the measurement results of the organic matter concentration measurement unit 26C of the measurement unit 26, and adjust the rate of reduction in the concentration of dissolved organic matter contained in the transfer water discharged from the cathode liquid tank 241.

[0173] In the organic hydride production apparatus 20C, transition water separated from the cathode fluid CL in the cathode fluid tank 241 is supplied to the aeration tank 251. Thereafter, oxygen gas separated from the anolyte AL in the anolyte tank 231 is supplied as an aeration gas to the aeration tank 251 via the oxygen gas supply line L21, and nitrogen gas in the nitrogen gas storage unit 411 is supplied as an aeration gas to the aeration tank 251 via the nitrogen gas supply line L31. The oxygen gas and nitrogen gas separate organic matter dissolved in the transition water discharged from the cathode fluid tank 241 from the transition water, reducing the concentration of the organic matter dissolved in the transition water, thereby obtaining aerated transition water with a reduced concentration of dissolved organic matter.

[0174] The organic hydride production apparatus 20C includes an aeration unit 25C, which has a nitrogen gas supply unit 41 and an oxygen gas supply line L21. The aeration unit 25C supplies nitrogen gas as aeration gas to the transition water in the aeration tank 251, in addition to the oxygen gas separated from the anolyte AL in the anolyte tank 231. This allows the aeration unit 25C to effectively use the oxygen gas to separate organic matter dissolved in the transition water contained in the cathode fluid CL discharged from the electrolytic cell 21, while also separating the organic matter dissolved in the transition water contained in the cathode fluid CL discharged from the electrolytic cell 21 with increased accuracy. Therefore, the organic hydride production apparatus 20C can efficiently reduce the concentration of organic matter dissolved in the transition water with increased accuracy.

[0175] As described above, the organic hydride production systems 1A to 1C can efficiently produce organic hydrides directly from energy such as renewable energy using a material to be hydrided without passing through hydrogen gas, as an energy carrier for transporting and storing energy-derived hydrogen. Therefore, the organic hydride production systems 1A to 1C can be effectively used as devices for producing energy carriers used for transporting and storing power generated by the power supply unit 10. In particular, by using the organic hydride production systems 1A to 1C, renewable energy can be transported and stored via organic hydrides, allowing the renewable energy to be used efficiently and without waste. Therefore, the organic hydride production systems 1A to 1C can be suitably used for producing energy carriers for transporting and storing renewable energy.

[0176] In this embodiment, the organic hydride manufacturing apparatuses 20A to 20C control the operation of the organic hydride manufacturing apparatuses 20A to 20C, such as controlling the power supplied from the power supply unit 22 to the electrolytic cell 21, using the control unit 27 based on the measurement results of the measurement unit 26. However, the operation of the organic hydride manufacturing apparatuses 20A to 20C may also be controlled appropriately and as needed by an operator or the like.

[0177] Although the embodiments have been described above, the above embodiments are presented as examples, and the present invention is not limited to the above embodiments. The above embodiments can be implemented in various other forms, and various combinations, omissions, substitutions, or modifications can be made without departing from the spirit of the invention. The above embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as set forth in the claims.

[0178] The embodiments of the present invention are specified, for example, by the following aspects. [1] An organic hydride manufacturing apparatus for manufacturing an organic hydride in an electrolytic cell having an electrolyte membrane, an anode electrode installed on one side of the electrolyte membrane, and a cathode electrode installed on the other side of the electrolyte membrane, comprising: an anolyte supply unit that supplies anolyte to the anode electrode; and an aeration unit that supplies a gas containing at least one of oxygen and nitrogen as an aeration gas to transition water separated from the cathode liquid, thereby separating organic matter dissolved in the transition water and supplying the transition water with a reduced concentration of the dissolved organic matter to the anolyte supply unit. [2] The organic hydride manufacturing apparatus according to [1], wherein the aeration gas is at least one of air, oxygen gas produced by oxidation of the anolyte at the anode electrode, and nitrogen gas. [3] The organic hydride manufacturing apparatus according to [1] or [2], wherein the aeration unit has an air supply line that supplies air to the aeration unit as the aeration gas. [4] The organic hydride manufacturing apparatus according to any one of [1] to [3], wherein the aeration unit is connected to the anolyte supply unit and has an oxygen gas supply line for supplying oxygen gas generated when water in the anolyte is oxidized at the anode electrode as the aeration gas. [5] The organic hydride manufacturing apparatus according to any one of [1] to [4], wherein the aeration unit has a nitrogen gas supply unit for supplying nitrogen gas as the aeration gas, and the nitrogen gas supply unit has: a nitrogen gas storage unit for storing the nitrogen gas; and a nitrogen gas supply line connecting the aeration unit and the nitrogen gas storage unit. [6] The organic hydride manufacturing apparatus according to any one of [1] to [5], wherein the aeration unit reduces the concentration of organic matter dissolved in the transferred water to a predetermined value or less. [7] The organic hydride manufacturing apparatus according to any one of [1] to [6], further comprising a cathode fluid supply unit that supplies the cathode electrode with the cathode fluid and separates the migration water from the cathode fluid discharged from the electrolytic cell.[8] The organic hydride manufacturing apparatus according to [7], wherein the cathode fluid supply unit comprises: a cathode fluid tank for storing the cathode fluid; and cathode piping for circulating the cathode fluid between a cathode chamber accommodating the cathode electrode and the cathode fluid tank, wherein the cathode fluid tank separates the transition water and hydrogen gas contained in the cathode fluid discharged from the electrolytic cell. [9] The organic hydride manufacturing apparatus according to any one of [1] to [8], wherein the aeration unit comprises: an aeration tank for storing the transition water; and a circulation line connecting the aeration tank and the anode fluid supply unit.

[10] The organic hydride manufacturing apparatus according to [9], wherein the circulation line comprises an organic substance concentration measuring unit for measuring the concentration of organic matter in the transition water.

[11] The organic hydride manufacturing apparatus according to any one of [1] to

[10] , wherein the organic matter dissolved in the transition water includes at least one of a material to be hydrided and an organic hydride.

[12] An organic hydride production system comprising: an organic hydride production apparatus that produces an organic hydride in an electrolytic cell having an electrolyte membrane, an anode electrode installed on one side of the electrolyte membrane, and a cathode electrode installed on the other side of the electrolyte membrane, and a power supply unit that supplies power to the organic hydride production apparatus, wherein the organic hydride production apparatus comprises: a power supply unit that supplies power to the electrolytic cell, an anolyte supply unit that supplies anolyte to the anode electrode, and an aeration unit that supplies a gas containing at least one of oxygen and nitrogen as an aeration gas to transition water separated from the cathode liquid to separate organic matter dissolved in the transition water and supply the transition water with a reduced concentration of dissolved organic matter to the anolyte supply unit.

[13] The organic hydride production system according to

[12] , wherein the power supply unit supplies at least one of electricity derived from renewable energy and electricity derived from fossil fuels to the power supply unit of the organic hydride production apparatus.

[14] The organic hydride manufacturing system according to

[13] , wherein the power supply unit supplies the renewable energy-derived power and the fossil fuel-derived power to the power supply unit.

[15] A method for reusing transition water in an electrolytic cell for producing organic hydride, the method comprising: an aeration step of supplying a gas containing at least one of oxygen and nitrogen as an aeration gas to transition water separated from cathode fluid discharged from the electrolytic cell, thereby separating organic matter dissolved in the transition water; and a circulation step of supplying the transition water, in which the concentration of dissolved organic matter has been reduced, to an anode fluid supply unit that supplies anode fluid to the anode electrode.

[0179] This application claims priority based on Japanese Patent Application No. 2024-73084, filed with the Japan Patent Office on April 26, 2024, and incorporates the entire contents of said application by reference.

[0180] 1A, 1B, 1C Organic hydride production system 10 Power supply unit 11 First power supply unit 12 Second power supply unit 20A, 20B, 20C Organic hydride production apparatus 21 Electrolytic cell 22 Power supply unit 23 Anolyte supply unit 24 Catholyte supply unit 25A, 25B, 25C Aeration unit 26 Measurement unit 26A Voltage measurement unit 26B Current measurement unit 26C Organic substance concentration measurement unit 26D Ion conductive substance concentration measurement unit 27 Control unit 31 Membrane electrode assembly 34 Anode chamber 35 Cathode chamber 41 Nitrogen gas supply unit 231 Anolyte tank 232 Anode piping 233 Anode pump 241 Catholyte tank 242 Cathode piping 243 Cathode pump 244 Separation unit 251 Aeration tank 311 Electrolyte membrane 312 Anode electrode 313 Cathode electrode 313A Cathode electrode layer 313B Liquid diffusion layer 411 Nitrogen gas reservoir L11 Air supply line L12 Circulation line L13 Dissolved substance removal line L21 Oxygen gas supply line L31 Nitrogen gas supply line AL Anolyte CL Catholyte

Claims

1. An organic hydride manufacturing apparatus for manufacturing organic hydride in an electrolytic cell having an electrolyte membrane, an anode electrode installed on one side of the electrolyte membrane, and a cathode electrode installed on the other side of the electrolyte membrane, comprising: an anolyte supply unit that supplies anolyte to the anode electrode; and an aeration unit that supplies a gas containing at least one of oxygen and nitrogen as an aeration gas to transition water separated from the cathode liquid, thereby separating organic matter dissolved in the transition water, and supplying the transition water with a reduced concentration of dissolved organic matter to the anolyte supply unit.

2. The organic hydride manufacturing apparatus according to claim 1, wherein the aeration gas is at least one of air, oxygen gas generated by oxidation of the anolyte at the anode electrode, and nitrogen gas.

3. The organic hydride manufacturing apparatus according to claim 1 or 2, wherein the aeration section has an air supply line for supplying air to the aeration section as the aeration gas.

4. The organic hydride manufacturing apparatus according to claim 1 or 2, wherein the aeration unit has an oxygen gas supply line connected to the anolyte supply unit for supplying oxygen gas generated when the water in the anolyte is oxidized by the anode electrode as the aeration gas.

5. The organic hydride manufacturing apparatus according to claim 1 or 2, wherein the aeration section has a nitrogen gas supply section that supplies nitrogen gas as the aeration gas, and the nitrogen gas supply section has: a nitrogen gas storage section that stores the nitrogen gas; and a nitrogen gas supply line that connects the aeration section and the nitrogen gas storage section.

6. An organic hydride manufacturing apparatus according to claim 1 or 2, wherein the aeration section reduces the concentration of organic matter dissolved in the transition water to a predetermined value or less.

7. An organic hydride manufacturing apparatus according to claim 1 or 2, further comprising a cathode fluid supply section for supplying the cathode fluid to the cathode electrode and separating the migration water from the cathode fluid discharged from the electrolytic cell.

8. The organic hydride manufacturing apparatus according to claim 7, wherein the cathode fluid supply unit comprises: a cathode fluid tank for storing the cathode fluid; and cathode piping for circulating the cathode fluid between a cathode chamber accommodating the cathode electrode and the cathode fluid tank, and the cathode fluid tank separates the migration water and hydrogen gas contained in the cathode fluid discharged from the electrolytic cell.

9. The organic hydride manufacturing apparatus according to claim 1 or 2, wherein the aeration section comprises: an aeration tank for storing the migration water; and a circulation line connecting the aeration tank and the anode fluid supply section.

10. The organic hydride manufacturing apparatus according to claim 9, further comprising an organic substance concentration measuring unit in the circulation line for measuring the organic substance concentration in the transition water.

11. An organic hydride manufacturing apparatus according to claim 1 or 2, wherein the organic matter dissolved in the transition water includes at least one of a material to be hydrided and an organic hydride.

12. An organic hydride production system comprising: an organic hydride production apparatus for producing an organic hydride in an electrolytic cell having an electrolyte membrane, an anode electrode installed on one side of the electrolyte membrane, and a cathode electrode installed on the other side of the electrolyte membrane; and a power supply unit for supplying power to the organic hydride production apparatus, wherein the organic hydride production apparatus comprises: a power supply unit for supplying power to the electrolytic cell; an anolyte supply unit for supplying anolyte to the anode electrode; and an aeration unit for supplying a gas containing at least one of oxygen and nitrogen as an aeration gas to transition water separated from the cathode liquid, thereby separating organic matter dissolved in the transition water, and supplying the transition water with a reduced concentration of dissolved organic matter to the anolyte supply unit.

13. The organic hydride manufacturing system according to claim 12, wherein the power supply unit supplies at least one of electricity derived from renewable energy and electricity derived from fossil fuel to the power supply unit of the organic hydride manufacturing apparatus.

14. The organic hydride manufacturing system according to claim 13, wherein the power supply unit supplies the renewable energy-derived power and the fossil fuel-derived power to the power supply unit.

15. A method for recycling transition water in an electrolytic cell for producing organic hydride, the method comprising: an aeration step of supplying a gas containing at least one of oxygen and nitrogen as an aeration gas to transition water separated from cathode fluid discharged from the electrolytic cell, thereby separating organic matter dissolved in the transition water; and a circulation step of supplying the transition water, the concentration of which has been reduced, to an anode fluid supply unit that supplies anode fluid to the anode electrode.

Images