JP2005129291A - Fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a clean fuel cell of which a liquid organic hydride is directly made a fuel that is stable under normal temperature and pressure, and that is superior in safety, handling ability, and hydrogen storage amount, and which is superior in mountablity and safety, and which exhausts few carbon dioxide or the like. <P>SOLUTION: This is the fuel cell provided with a heating part 20 to heat cyclohexane and make it into a gas state, a fuel pole electrode 28 provided with a fuel supplying port 34 to supply the cyclohexane heated by the heating part 20 and a recovered material exhaust port 38 to exhaust benzene, an air pole electrode 28 which has an air pole supplying port 40 to which oxygen is supplied and an exhaust port 42 to exhaust water, and an electrolyte film 30 pinched by the fuel pole electrode 28 and the air pole electrode 32. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fuel cell using a liquid organic hydride having 5 or more carbon atoms as a direct fuel.

  In recent years, reserves of fossil fuels have drastically decreased, and alternative fuels have been demanded. As such an alternative fuel, hydrogen gas is attracting attention because it can be easily generated, and fuel cells that use hydrogen gas as a clean energy source that does not generate carbon dioxide after combustion are actively developed. It is done. In addition, research on the use of such fuel cells for on-vehicle applications has also been actively conducted, and the issue is how to increase the mountability (volume and weight), safety, and the amount of raw fuel. It has become.

  A fuel cell uses hydrogen gas as a direct fuel, and generates power by a reaction reverse to the reaction of generating water from hydrogen and oxygen. For example, a polymer electrolyte fuel cell, which is one type of fuel cell, is configured to include a stack in which a plurality of cells formed by sandwiching a polymer electrolyte membrane from both sides of a fuel electrode and an oxygen electrode are stacked. .

  In a conventional fuel cell, hydrogen gas is supplied to the fuel electrode as fuel, and air is supplied to the oxygen electrode as oxidant. Hydrogen supplied to the fuel electrode of the fuel cell generates hydrogen ions by a reaction with a catalyst provided in the fuel electrode, and the hydrogen ions pass through the solid polymer electrolyte membrane and electrochemically react with oxygen at the oxygen electrode. Electricity is generated by causing a reaction.

  However, since hydrogen gas is a gas at room temperature, there is a problem that it is very difficult to store and transport it. For this reason, conventionally, a fuel cell has been developed in which organic hydride such as decalin and cyclohexane is used as a raw fuel, and hydrogen is extracted from the organic hydride in a molecular form and supplied (see, for example, Patent Document 1).

  However, since the fuel cell for extracting hydrogen molecules from the organic hydride as described above thermally decomposes the organic hydride to extract the hydrogen molecules and supplies it to the fuel electrode of the fuel cell, There are many technical, cost and safety regulations in terms of (cruising range), mountability and safety, and further improvements are required to satisfy all of these.

  In addition to fuel cells that use hydrogen gas directly as a fuel cell, there are known fuel cells that use liquid methanol directly as fuel under normal temperature and pressure.

  However, in the fuel cell using methanol as a direct fuel, carbon dioxide is generated along with the reaction when generating electric power. Since such carbon dioxide causes global warming, it is not suitable as a clean energy source. In addition, the generated electric energy is as low as about 0.5 V and is not sufficient.

JP 2002-184436 A

  In order to solve the above problems, the present invention uses a liquid organic hydride which is stable at ordinary temperature and pressure and is excellent in safety, handling and hydrogen storage as a direct fuel, and is excellent in mountability and safety. It aims at providing the clean fuel cell which discharge | emits etc. hardly.

  In order to solve the above-mentioned problems, the fuel cell of the present invention includes a first heating means for heating an organic hydride having a total carbon number of 5 or more to make it gaseous, and the organic heated by the first heating means. A fuel electrode provided with a supply port for supplying hydride and a discharge port for discharging the dehydrogenated compound of the organic hydride, an air electrode electrode provided with a supply port for supplying oxygen and a discharge port for discharging water And an electrolyte membrane sandwiched between the fuel electrode and the air electrode.

  According to the fuel cell of the present invention, a liquid organic hydride that is stable under normal temperature and normal pressure and that is excellent in safety, handleability, and hydrogen storage amount is used as a direct fuel for the fuel cell. It can be designed compactly.

  The organic hydride in the present invention uses an organic hydride having 5 or more carbon atoms. The upper limit of the carbon number of the organic hydride in the present invention is not particularly limited, but is preferably 20 or less, and more specifically, it is more preferable to use a liquid organic hydride having 5 to 9 carbon atoms.

  Examples of the organic hydride include acyclic n-hexane, iso-octane, and the like, and cyclic monocyclic compounds such as cyclohexane, methylcyclohexane, dimethylcyclohexane, 1,3,5-trimethylcyclohexane, Examples include bicyclic compounds such as decalin, methyldecalin, and tetralin (tetrahydronaphthalene), and tricyclic compounds such as tetradecahydroanthracene. As the organic hydride used as a direct fuel in the present invention, cyclohexane, methylcyclohexane, decalin, methyldecalin, tetralin and methyltetralin are particularly preferred, and cyclohexane and methylcyclohexane are more preferred.

  The fuel cell of the present invention has a high electromotive force because it uses an organic hydride having 5 or more carbon atoms. For example, when cyclohexane is used as a direct fuel, about 1 V (650 KJ) as shown in the following reaction formula. Of electrical energy. Furthermore, in the fuel cell of the present invention, only the dehydrogenated compound and water are generated during the power generation reaction, and there is no generation of carbon dioxide or the like.

C ₆ H ₁₂ + 3 / 2O ₂ → C ₆ H ₆ + 3H ₂ O + 651 kJ

  Since the organic hydride dehydrogenation compound having 5 or more carbon atoms tends to be in a liquid or solid state, it must be promptly recovered in order to prevent a decrease in power generation efficiency. According to the fuel cell of the present invention, the organic hydride heated and gasified by the first heating means is supplied to the fuel electrode, so that the dehydration compound of the organic hydride can be quickly brought into the fuel electrode in the gaseous state. It can be discharged (recovered). As a result, the fuel electrode is lowered to a predetermined temperature or lower to prevent the dehydrogenation compound from becoming liquid or solid, and adheres to the catalyst or the like provided in the fuel electrode, thereby reducing the power generation efficiency. Can do.

  The heating temperature of the organic hydride by the first heating means is not particularly limited as long as the supplied organic hydride is a temperature at which a gaseous state can be maintained and the dehydrogenated compound in the fuel electrode can be maintained at a gaseous state. For example, when cyclohexane or methylcyclohexane is used as the organic hydride, it is preferably heated to about 80 to 110 ° C. by the first heating means.

  The organic hydride emits hydrogen ions and electrons on a catalyst provided on the fuel electrode to generate a dehydrogenated compound. As the dehydrogenation compound, for example, when cyclohexane is used as the organic hydride, benzene is produced as the dehydrogenation compound, and when methylcyclohexane is used, toluene is produced as the dehydrogenation compound.

  The fuel cell of the present invention can be configured such that the first heating means heats the organic hydride by an oxidation reaction of the dehydrogenated compound discharged from the discharge port. As the heat source of the first heating means, a known heating means such as a heating medium such as silicone oil or a heater can be used as appropriate. However, according to the fuel cell of the present invention, it is generated by the oxidation reaction of the dehydrogenated compound. By using reaction heat for heating the organic hydride, heating efficiency can be increased and energy saving can be achieved.

  In addition, the fuel cell of the present invention may further comprise a second heating means for heating the fuel electrode.

  According to the fuel cell of the present invention, by providing the second heating means for heating the fuel electrode, and heating the fuel electrode itself, the dehydrogenation compound can be discharged (recovered) more smoothly. it can. Thereby, it can prevent that the said dehydrogenation compound liquefies or solidifies and stays in a fuel electrode.

  As the second heating means, a heating medium such as a heater or silicone oil can be used. The second heating means is not particularly limited as long as the temperature is set so that the dehydrogenated compound in the fuel electrode maintains a gaseous state and does not affect the electrolyte membrane. For example, when cyclohexane is used as the organic hydride, it is preferable to maintain the temperature in the electrode as much as possible at about 110 ° C.

  The fuel cell of the present invention further includes a third heating unit for heating the organic hydride, and the first heating unit heats the organic hydride heated by the third heating unit. Can be configured.

  According to the present invention, the organic hydride heated by the first heating means can be preliminarily heated by providing the third heating means for heating the organic hydride prior to the heating by the first heating means. . Thereby, the heating burden in a 1st heating means can be disperse | distributed and the improvement of energy efficiency can be aimed at.

  As the heat source of the third heating means, a heating medium such as a heater or silicone oil can be used as described above. For example, the third heating means and the flow path of the dehydrogenation compound discharged from the fuel electrode are each constituted by piping, and the piping in the third heating means and the piping through which the dehydrogenation compound flows are installed in the vicinity. By doing so, the exhaust heat of the dehydrogenated compound can be converted into heat used for heating the organic hydride by heat exchange.

  The fuel cell of the present invention is a first heating means for heating an organic hydride having a total carbon number of 5 or more to make it gaseous, and a supply for supplying the organic hydride heated by the first heating means. A fuel electrode electrode tube formed of a tubular fuel electrode catalyst having a port and a discharge port for discharging a dehydrogenated compound of the organic hydride, and through which the organic hydride supplied from the supply port flows, and oxygen is supplied An outer wall having a supply port and a discharge port from which water is discharged, and a tubular air electrode catalyst installed inside the outer wall, and between the outer wall and the outer peripheral surface of the tubular air electrode catalyst An air electrode tube in which oxygen is allowed to flow, and an electrolyte membrane sandwiched between an outer peripheral surface of the tubular fuel electrode catalyst and an inner peripheral surface of the tubular air electrode catalyst can be provided. .

  According to the present invention, it is possible to save space and improve reaction efficiency by configuring a fuel cell with a tubular fuel electrode tube and an air electrode tube. Moreover, the fuel cell of this aspect may be used alone, or a plurality of fuel cells may be connected in parallel.

  According to the present invention, an organic hydride that is stable under normal temperature and normal pressure and has excellent safety, handleability, and hydrogen storage capacity is directly used as a fuel, is excellent in mountability and safety, and does not substantially discharge carbon dioxide. A fuel cell can be provided.

  Hereinafter, an embodiment of a fuel cell system including a fuel cell of the present invention will be described with reference to the drawings. In the following embodiment, a case where cyclohexane is used as the organic hydride will be described as an example. However, the present invention is not limited to these embodiments.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic diagram showing the configuration of the fuel cell system according to the first embodiment. In FIG. 1, a fuel cell system 10 includes a fuel cell 12 and a fuel tank 14, and generates electricity by supplying liquid cyclohexane stored in the fuel tank 14 directly to the fuel cell 12 as fuel.

  In FIG. 1, the fuel cell 12 includes a cell unit 16, a heat exchange unit 18, a heating unit 20, and a heater 22, and power is supplied to an external device 26 through an external circuit 24 connected to the cell unit 16. It is comprised so that it can supply.

In the present embodiment, the cell portion 16 is composed of a fuel electrode 28, an electrolyte membrane 30, and an air electrode 32. The fuel electrode 28 and the air electrode 32 are electronic via an external circuit 24. (E ⁻ ) is movable. The cell unit 16 generates power by the cyclohexane directly supplied as fuel emitting hydrogen ions and electrons at the fuel electrode 28, and the released electrons move to the air electrode 32 via the external circuit 24. .

  The fuel electrode 28 is provided with a fuel supply port 34 and a recovered material discharge port 36 so that liquid cyclohexane as a direct fuel can be supplied and benzene as a dehydrogenated compound of cyclohexane can be recovered. It is configured. Further, the fuel electrode 28 is provided with an electrode 38 composed of a catalyst and a diffusion member and connected to one end of the external circuit 24, so that the supplied cyclohexane can reach the catalyst through the diffusion member. Yes.

  As the catalyst provided in the electrode 38, a known dehydrogenation catalyst can be used. For example, carbon support using a noble metal-based metal such as Pt, Pt—Rh, Pt—Ir, Pt—Re, Pt—W or the like. A Pt catalyst, a carbon-supported Pt—Ir composite metal catalyst, a carbon-supported Pt—Re composite metal catalyst, a carbon-supported Pt—W composite metal catalyst, a catalyst using a nickel-based metal, or the like can be used. The electrode 38 can be formed by mixing a supported catalyst, a polymer membrane solution used for the electrolyte membrane 30, and a binder.

  When gaseous cyclohexane heated to about 110 ° C. by the heating unit 20 is supplied to the fuel electrode 28, the cyclohexane reacts with the catalyst of the electrode 38 to release hydrogen ions and electrons for dehydration. Benzene, an elemental compound, is produced. Hydrogen ions released from cyclohexane move to the air electrode 32 through the electrolyte membrane 30 provided so as to be in contact with the electrode 38. On the other hand, since the electrolyte membrane 30 blocks the movement of electrons, the electrons emitted from the cyclohexane move to the air electrode 32 through the electrode 38.

  Further, since the cyclohexane heated by the heating unit 20 is supplied to the fuel electrode 28, the internal temperature is kept at about 110 ° C. For this reason, the benzene produced | generated by the fuel electrode 28 can be kept gaseous, and it can discharge | emit (collect | recover) easily from the collection | recovery discharge port 36. FIG.

  The electrolyte membrane 30 is a membrane that allows only hydrogen ions out of the electrons and hydrogen ions generated at the electrode 38 to pass therethrough, and can be composed of, for example, a polymer membrane such as a perfluorosulfonic acid membrane.

  The air electrode 32 is provided with an air supply port 40 so that air containing oxygen is supplied. Further, the air electrode 32 is provided with an electrode 44 composed of a catalyst and a diffusing member and connected to the other end of the external circuit 24 so that hydrogen ions and oxygen that have moved through the electrolyte membrane 30 react with each other. To produce water. Further, the air electrode 32 is provided with a discharge port 42 so that water generated by the air electrode 32 can be discharged.

  As the catalyst provided in the electrode 44, the same catalyst as that of the electrode 38 described above can be used. The electrode 44 can be formed by mixing a supported catalyst, a polymer membrane solution used for the electrolyte membrane 30, and a binder.

  The electrode 44 is installed in the cell portion 16 so as to be in contact with the electrolyte membrane 30. The hydrogen ions that have moved through the electrolyte membrane 30 react with oxygen contained in the air supplied from the air supply port 40, receive the electrons that have moved through the external circuit 24, and generate water. The water produced by the reaction between hydrogen ions and oxygen is discharged from the discharge port 42 to the outside of the system.

  In FIG. 1, the heat exchanging unit 18 preliminarily heats cyclohexane supplied from the fuel tank 14 via the pump P1. As shown in FIG. 1, the heat exchanging unit 18 includes a heat absorption tube 46 and a heat radiating tube 48, and the heat absorption tube 46 can absorb the heat released from the heat radiating tube 48.

  The endothermic pipe 46 is circulated with cyclohexane stored in the fuel tank 14 in the pipe, and the cyclohexane in the endothermic pipe 46 is heated by the heat released from the heat radiating pipe 48. One end of the heat absorption pipe 46 is connected to a supply pipe 52 connected to the fuel storage section 50 of the fuel tank 14. The supply pipe 52 is provided with a pump P1, and liquid cyclohexane stored in the fuel storage section 50 is supplied by driving the pump P1.

  The other end of the endothermic tube 46 is connected to one end of the heating tube 54 of the heating unit 20 so that liquid cyclohexane preliminarily heated in the heat exchanging unit 18 can be supplied to the heating unit 20. Yes.

  In the heat radiating pipe 48, benzene discharged from the cell portion 16 circulates in the pipe. At this time, the benzene discharged from the cell portion 16 has residual heat, and the residual heat is released from the heat radiating pipe 48 as released heat. One end of the heat radiating pipe 48 is connected to the exhaust pipe 56 of the heat exchanging section 18 so that the remainder of benzene used for heating by the oxidation reaction in the heating section 20 is supplied. In addition, the other end of the heat radiating pipe 48 is connected to a discharge pipe 60 provided with a pump P2 at one end connected to the recovered substance storage part 58 of the fuel tank 14 so that benzene can be discharged to the recovered substance storage part 58. It has become.

  The heat exchange unit 18 is configured such that heat released from the heat radiating pipe 48 is absorbed by the heat absorbing pipe 46. For this reason, the heat absorption pipe 46 and the heat radiating pipe 48 are installed in the heat exchange unit 18 so that heat exchange is possible. Moreover, as long as heat exchange is possible, the shape of the heat absorption pipe | tube 46 and the thermal radiation pipe 48 will not be specifically limited, For example, spiral shape and tube shape may be sufficient.

  In FIG. 1, the heating unit 20 includes a heating tube 54 and a discharge tube 56 provided with a plurality of reactors 62, and heats liquid cyclohexane by an oxidation reaction of benzene discharged from the cell unit 16. Thus, gaseous cyclohexane can be formed.

  One end of the heating tube 54 is connected to the endothermic tube 46 of the heat exchanging unit 18, and cyclohexane preliminarily heated by the heat exchanging unit 18 flows through the tube. The other end of the heating tube 54 is connected to the fuel supply port 34 of the cell unit 16, and is configured so that cyclohexane heated by the heating unit 20 and in the gaseous state can be supplied to the cell unit 16.

  Further, one end of the discharge pipe 56 is connected to the collected product discharge port 36 of the cell unit 16 so that benzene generated in the cell unit 16 flows through the pipe. The other end of the discharge pipe 56 is connected to the heat radiating pipe 48 of the heat exchange unit 18 so that the remaining benzene used for the oxidation reaction can be supplied to the heat exchange unit 18.

  The heating unit 20 is provided with a plurality of reactors 62 that generate heat due to the oxidation reaction of benzene as a heat source, and the liquid cyclohexane flowing through the heating tube 54 is turned into a gas (about 110 ° C.) by the heat from the reactor 62. Heat to a degree). The reactor 62 provided in the discharge pipe 56 is provided with an air supply port and a plug (not shown) so that benzene and air are supplied. The air and benzene supplied into the reactor 62 can generate an oxidation reaction by the ignition of the plug to generate heat. The reactor 62 may be provided with a known oxidation catalyst to promote the oxidation reaction between benzene and air.

  In FIG. 1, the heater 22 is provided to heat the fuel electrode 28 of the cell portion 16. By heating the fuel electrode 28 with the heater 22, it is possible to prevent benzene from solidifying or precipitating in the fuel electrode 28 and lowering the power generation efficiency.

  In FIG. 1, the fuel tank 14 includes a fuel storage unit 50 and a collected product storage unit 58. The fuel storage unit 50 stores cyclohexane used as a direct fuel for the fuel cell 12, and is configured to supply cyclohexane to the heat exchange unit 18 of the fuel cell 12. Further, benzene recovered from the cell unit 16 is stored in the recovered material storage unit 58.

  The fuel storage unit 50 and the recovered material storage unit 58 are formed of a stretchable container such as a resin bag, and the volume thereof can be changed according to the internal capacity. Further, the fuel storage unit 50 and the collected material storage unit 58 can be configured to be detachable. For example, when the amount of benzene in the recovered material storage unit 58 exceeds a certain amount, it may be sucked out from the recovered material storage unit 58, or the recovered material storage unit 58 may be removed and replaced with a new empty recovered material storage unit 58. It may be possible. Similarly, the fuel storage unit 50 is configured to be detachable, and when the cyclohexane in the fuel storage unit 50 is exhausted, the fuel storage unit 50 is configured to be replaceable with a new fuel storage unit 50 that is fully filled. You can also.

  Next, a power generation mechanism using the fuel cell of the present invention will be described. First, when liquid cyclohexane stored in the fuel storage section 50 of the fuel tank 14 is supplied to the heat absorption pipe 46 of the heat exchange section 18 by the pump P1, the cyclohexane flows from the heat dissipation pipe 48 while flowing through the heat absorption pipe 46. It absorbs the released heat and is heated.

  Next, the liquid cyclohexane preliminarily heated in the heat exchange unit 18 is supplied to the heating unit 20. When the liquid cyclohexane supplied to the heating unit 20 flows through the heating tube 54, it is heated and becomes gaseous by the heat from the reactor 62. At this time, benzene discharged from the cell portion 16 is supplied to the reactor 62, and the cyclohexane in the heating tube 54 is heated by the heat of the oxidation reaction.

  The cyclohexane heated in the heating unit 20 and turned into a gaseous state is supplied from the fuel supply port 34 to the fuel electrode 28 of the cell unit 16 and releases hydrogen ions and electrons at the electrode 38 to generate benzene. At this time, hydrogen ions released from the electrode 38 pass through the electrolyte membrane 30 and move to the electrode 44 of the air electrode 32. The electrons emitted from the electrode 38 move in the external circuit 24. The fuel cell of the present invention can supply electric power to an external device by this movement of electrons.

  The hydrogen ions that have moved to the electrode 44 react with oxygen supplied to the air electrode 32 from the air supply port 40 and electrons that have moved through the external circuit 24 to generate water. Water generated at the air electrode 32 is discharged from the discharge port 42 to the outside of the system.

  On the other hand, heated cyclohexane is supplied to the fuel electrode 28 and is further heated by the heater 22. For this reason, the benzene produced | generated by the fuel electrode 28 can be collect | recovered from the collection | recovery discharge port 36 in a gaseous state, without liquefying or depositing benzene which is a dehydrogenation compound in the fuel electrode 28. FIG. As a result, it is possible to prevent benzene, which is a dehydrogenated compound, from liquefying or precipitating at the fuel electrode 28, thereby preventing a reduction in the electromotive force of the fuel cell, and supplying power stably to an external device. it can.

  The benzene discharged from the recovered material discharge port 36 is supplied to the heating unit 20 and used to heat the cyclohexane supplied to the cell unit 16. Thus, according to the fuel cell of the present embodiment, the cyclohexane, which is the fuel, is directly heated by the oxidation reaction of the benzene recovered as a recovered product, and thus the energy efficiency in the apparatus is excellent.

Also, benzene that has not been used in the oxidation reaction for heating cyclohexane in the heating unit 20 flows through the discharge pipe 56 as it is and is supplied to the heat radiating pipe 48 of the heat exchange unit 18. Since benzene supplied to the heat radiating pipe 48 has a certain amount of residual heat, it releases heat when it flows through the heat radiating pipe 48 and is cooled by heat exchange with cyclohexane in the heat absorbing pipe 46. Thus, according to this Embodiment, since the cyclohexane preliminarily heated by the heat exchange part 18 is supplied to the heating part 20, the heating burden in the heating part 20 can be reduced and it is excellent in energy efficiency.

  The benzene discharged from the heat exchange unit 18 is stored in the collected material storage unit 58 of the fuel tank 14 via the pump P2.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. The cell part in this Embodiment is a tubular cell part which can be diverted with the cell part in 1st Embodiment, and description is abbreviate | omitted about the overlapping part. In the present embodiment, a mode in which liquid cyclohexane is used as a direct fuel will be described.

  FIG. 2 is a schematic diagram showing the configuration of the cell unit in the second embodiment. In FIG. 2, the cell unit 70 is configured to cover a fuel electrode tube 72, an electrolyte membrane 74, and an air electrode electrode 76 with an outer wall 78, and the fuel electrode electrode tube 72, the air electrode electrode 76, and the like. The electron can move through the external circuit 24.

  In the present embodiment, the cell portion 70 is tubular, and cyclohexane supplied directly as fuel emits hydrogen ions and electrons at the inner wall of the tube forming the fuel electrode, and the emitted electrons are external circuit 24. Power is generated by moving to the air electrode 32 via the.

  The fuel electrode tube 72 is a tube formed of a catalyst, and is configured such that cyclohexane flows through the tube. The fuel electrode tube 72 is provided with a fuel supply port 80 and a recovered material discharge port 82 so that cyclohexane as a direct fuel is supplied and benzene as a dehydrogenated compound of cyclohexane can be recovered. It is configured. Furthermore, one end of the external circuit 24 is connected to the fuel electrode tube 72.

  As the catalyst for forming the fuel electrode tube 72, a known dehydrogenation catalyst can be used, and the same catalyst as exemplified above can be used.

  When gaseous cyclohexane heated to about 110 ° C. by the heating unit 20 is supplied into the tube of the fuel electrode tube 72, it reacts with the catalyst forming the wall surface of the tube, and hydrogen ions and electrons are converted. Release benzene, which is a dehydrogenated compound. Hydrogen ions released from cyclohexane move to the air electrode 76 through the electrolyte membrane 74 provided so as to be in contact with the outer wall surface of the fuel electrode tube 72. On the other hand, since the electrolyte membrane 74 blocks the movement of electrons, the electrons emitted from the cyclohexane move to the air electrode 76 through the external circuit 24.

  Moreover, since the cyclohexane heated by the heating unit 20 is supplied to the fuel electrode tube 72, the internal temperature is maintained at about 110 ° C. For this reason, the benzene produced | generated with the fuel electrode tube 72 can be kept gaseous, and it can discharge | emit (collect | recover) easily from the collection | recovery discharge port 82. Further, the fuel electrode tube 72 may be additionally provided with a heating means such as a heater for heating the inside of the fuel electrode tube.

  The positional relationship among the fuel electrode tube 72, the electrolyte membrane 74, the air electrode electrode 76, and the outer wall 78 will be described with reference to FIG. 3 is a cross-sectional view taken along the line AA 'of FIG. As shown in FIG. 3, the cell portion 70 is provided with an electrolyte membrane 74 so as to be sandwiched between the outer wall surface of the fuel electrode tube 72 and the inner wall surface of the air electrode electrode 76. The cyclohexane supplied to the inside 84 of the fuel electrode tube 72 reacts with the catalyst forming the wall surface of the fuel electrode tube 72 to release hydrogen ions and electrons on the wall surface to generate benzene.

  Hydrogen ions released from the wall surface of the fuel electrode tube 72 move to the air electrode 76 through the electrolyte membrane 74. As shown in FIG. 3, the air electrode 76 includes a tubular electrode 86 formed of a catalyst and is in contact with the electrolyte membrane 74 on the inner wall surface thereof. Further, the air flow passage formed on the wall surface of the outer wall 78. 88 is provided.

  The electrolyte membrane 74 is a membrane that allows only hydrogen ions out of electrons and hydrogen ions generated in the fuel electrode tube 72 to pass therethrough, and can be formed of, for example, a polymer membrane such as a perfluorosulfonic acid membrane.

  As shown in FIG. 2, the air electrode 76 is provided with an air supply port 90 so as to penetrate the outer wall 78 so that air containing oxygen is supplied. Further, one end of the external circuit 24 is connected to the tubular electrode 86. The oxygen supplied through the air supply port 90 stays so as to cover the outer peripheral surface of the tubular electrode 86 through the flow path 88 shown in FIG. 2, and the hydrogen ions and the external circuit that have moved through the electrolyte membrane 74 are retained. It reacts with the moving electrons to produce water.

  Further, the air electrode 76 is provided with a discharge port 92 so as to penetrate the outer wall 78, so that water generated on the outer peripheral surface of the tubular electrode 86 can be discharged. As the catalyst constituting the tubular electrode 86, the same catalyst as described above can be used.

  A power generation mechanism using the cell unit 70 will be described. When gaseous cyclohexane heated in the heating unit 20 in FIG. 1 is supplied from the fuel supply port 80 into the tube of the fuel electrode tube 72 formed of a catalyst, the inner wall surface of the fuel electrode tube 72 and cyclohexane Reacts to release hydrogen ions and electrons.

  The hydrogen ions released from the inner wall of the fuel electrode tube 72 move to the air electrode 76 through the electrolyte membrane 74. The electrons emitted from the inner wall of the fuel electrode tube 72 move to the air electrode 76 through the external circuit 24, and react with oxygen and hydrogen ions at the air electrode 76 to generate water.

  On the other hand, cyclohexane that has released electrons and hydrogen ions in the fuel electrode tube 72 generates benzene. Here, since the heated cyclohexane is supplied into the tube of the cell part 70, the temperature is maintained at a temperature at which benzene can exist in a gaseous state. For this reason, benzene does not liquefy or precipitate and the electromotive force is not lowered.

  The gaseous benzene produced in the fuel electrode tube 72 is recovered (discharged) from the recovered material discharge port 82 and is directly used for heating cyclohexane, which is the fuel, in the heating unit 20 and the heat exchange unit 18 in FIG. The fuel is stored in the collected material storage 58 of the fuel tank 14. Further, a plurality of cell units 70 may be mounted in parallel as shown in FIG. FIG. 4 is a schematic diagram showing an aspect in which a plurality of cell units in the second embodiment are mounted.

  According to the present embodiment, in addition to the effects in the first embodiment described above, by using a tubular cell portion as the cell portion, the fuel cell of the present invention can be designed in a compact manner, and mountability is improved. Can be improved.

It is the schematic which shows the structure of the fuel cell of this invention. It is the schematic which shows the structure of the cell part in 2nd Embodiment. FIG. 3 is a cross-sectional view taken along the line AA ′ of FIG. 2. It is the schematic which shows the aspect which mounted the cell part in 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Fuel cell system 12 Fuel cell 14 Fuel tank 16, 70 Cell part 18 Heat exchange part 20 Heating part 22 Heater 28 Fuel electrode 30, 74 Electrolyte membrane 32, 76 Air electrode 34, 80 Fuel supply port 36, 82 Collected material Discharge port 40, 90 Air supply port 42, 92 Discharge port 72 Fuel electrode electrode tube 78 Outer wall 88 Flow passage

Claims (5)

A first heating means for heating an organic hydride having a total carbon number of 5 or more to make it gaseous;
A fuel electrode provided with a supply port to which the organic hydride heated by the first heating means is supplied and a discharge port for discharging a dehydrogenated compound of the organic hydride;
An air electrode having a supply port for supplying oxygen and a discharge port for discharging water;
An electrolyte membrane sandwiched between the fuel electrode and the air electrode;
A fuel cell.   2. The fuel cell according to claim 1, wherein the first heating unit heats the organic hydride by an oxidation reaction of a dehydrogenated compound discharged from a discharge port of the fuel electrode.   The fuel cell according to claim 1, further comprising second heating means for heating the fuel electrode.   Furthermore, it has the 3rd heating means which heats the organic hydride, and the 1st heating means heats the organic hydride heated by the 3rd heating means. The fuel cell as described. A first heating means for heating an organic hydride having a total carbon number of 5 or more to make it gaseous;
A tube having a supply port for supplying the organic hydride heated by the first heating means and a discharge port for discharging a dehydrogenated compound of the organic hydride and through which the organic hydride supplied from the supply port circulates. An anode electrode tube formed of an anode catalyst of
An outer wall having a supply port for supplying oxygen and a discharge port for discharging water; a tubular air electrode catalyst installed in the outer wall; and the outer wall and an outer peripheral surface of the tubular air electrode catalyst; An air electrode tube in which the oxygen flows between
An electrolyte membrane sandwiched between an outer peripheral surface of the tubular fuel electrode catalyst and an inner peripheral surface of the tubular air electrode catalyst;
A fuel cell.

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