JP2003081601A - Hydrogen production/storage apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reaction efficiency of hydrogen addition reaction or dehydrogenation reaction used for storing or supplying hydrogen. SOLUTION: In the hydrogen production/storage apparatus utilizing the dehydrogenation reaction and the hydrogen addition reaction, a cylindrical member 17 to be a member for the dehydrogenation reaction or the hydrogen addition reaction is arranged, a catalyst 20 for carrying out the dehydrogeneration reaction or the hydrogen addition reaction of a hydrogen producing body or a hydrogen storing body is arranged in the lower side inner circumference of the cylindrical member 17, a liquefying cooling part 22 is arranged in the upper side of the cylindrical member 17, the cylindrical member 17 is arranged between a tank 18 provided with the hydrogen producing body or the hydrogen storing body and a tank 18 for recovering a material produced by the dehydrogenation reaction or the hydrogen addition reaction, the hydrogen producing body or the hydrogen storing body provided in the tank 16 is passed through the cylindrical member 17 to be sent to the tank 18 to be in contact with the catalyst 20, evaporated, cooled by the cooling part 22 and liquefied and the liquefied material is brought into contact with the catalyst 20 again to repeat a series of the operations.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrogen generating / storing device for generating or storing hydrogen as an energy source for fuel cells and the like.

[0002]

2. Description of the Related Art The amount of energy consumed is increasing year by year, and problems such as the power supply from power plants becoming unable to keep up, especially in urban areas, are occurring. Currently, about half of Japanese electric power depends on thermal power generation, about 30% to 40% on nuclear power, and the rest on hydroelectric power, wind power, and the like.

However, petroleum, which is a fuel for thermal power generation, is a fossil fuel and its supply is limited. Further, exhaust gas such as carbon dioxide and NOX generated after burning oil is a cause of deterioration of global environment including global warming. In addition, nuclear power is regarded as a problem in the treatment of radioactive waste or accidents at power plants.

However, in order to maintain and maintain a comfortable life, Japan is the only one who has to rely on thermal power generation and nuclear power generation while keeping an eye on some environmental problems and the risk of radiation generation. It is the current state of the world. In addition, hydroelectric power generation has problems such as unstable power supply depending on the season, deforestation associated with construction of a power plant, and low power generation efficiency.
It is declining as a power supply method. In addition, wind power generation and geothermal power generation are still costly,
It remains small.

On the other hand, turning to automobile fuels, hydrocarbon fuels such as gasoline, light oil and propane gas are mainly used at present. Recently, "environmentally friendly" has become a catchphrase, and hybrid vehicles that can switch between electricity and gasoline have been put into practical use in order to suppress exhaust gas as much as possible.
However, even in the case of hybrid vehicles, hydrocarbon fuels such as gasoline still have to be used.

From the current state of power generation and automobile development,
Recently, hydrogen fuel has been drawing attention. Hydrogen can be generated by electrolysis of water. Therefore, considering the electrolysis of seawater or river water, hydrogen fuel is inexhaustibly present. Further, hydrogen is a clean energy source that does not generate carbon dioxide after combustion. Due to these advantages, hydrogen is drawing attention as an alternative fuel for hydrocarbon fuels such as gasoline and petroleum.

[0007] However, since hydrogen is a gas at room temperature, it is more difficult to store and transport it than liquid or solid. Moreover, hydrogen is a flammable substance and explodes at a predetermined mixing ratio with air even in the presence of a slight electric spark. Therefore, hydrogen is a fuel that requires extremely careful handling. It is possible to store hydrogen in a high-pressure cylinder in a gas state, but the storage amount is limited and high-pressure encapsulation is costly.

As a technique for solving such a problem, as disclosed in Japanese Patent Laid-Open No. 7-192746, there is known a method of reacting hydrogen with a hydrogen storage alloy and storing it.
However, the hydrogen storage alloys such as La-Ni type and Ti-Fe type are heavy and have a problem as a portable hydrogen storage device. In addition, existing hydrogen storage alloys can store a maximum amount of hydrogen of only about 3% by weight, and there is also a demand for increasing the amount of hydrogen stored. Another problem is that the hydrogen storage alloy is expensive.

Therefore, hydrocarbons such as benzene and cyclohexane are attracting attention as a hydrogen storage method which is excellent in safety, transportability, storage capacity and cost reduction. Since these hydrocarbons are liquid at room temperature, they are excellent in transportability.

Benzene and cyclohexane are cyclic hydrocarbons having the same carbon number. Benzene is an unsaturated hydrocarbon having a double bond between carbons, whereas cyclohexane is a saturated hydrocarbon having no double bond. It is a hydrocarbon. Cyclohexane is obtained by the hydrogenation reaction of benzene, and benzene is obtained by the dehydrogenation reaction of cyclohexane. That is, it is possible to store or generate hydrogen by utilizing the hydrogenation / dehydrogenation reaction of these hydrocarbons.

[0011]

However, in order to put hydrogen generation and storage into practical use by utilizing a dehydrogenation reaction and a hydrogenation reaction typified by a reaction between benzene and cyclohexane, the reaction efficiency is further increased. There is a need. In particular, the action of the liquid raw material such as benzene or cyclohexane and the catalyst is a problem.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to enhance the reaction efficiency of a raw material required for hydrogen generation or storage.

[0013]

In order to achieve the above object, the present invention provides a hydrogen generator which releases hydrogen to be converted into an aromatic compound, and an aromatic compound which reacts with hydrogen to store the hydrogen. A hydrogen generating / storing device for generating or storing hydrogen by utilizing a dehydrogenation reaction or a hydrogen addition reaction with a hydrogen storage body, which is for a reaction for generating a dehydrogenation reaction or a hydrogen addition reaction. A tubular member to be a member is arranged in a tilted state, and a catalyst for performing a dehydrogenation reaction or a hydrogen addition reaction of a hydrogen generator or a hydrogen storage body is arranged on the inner surface of the cylindrical member on the lower side in the vertical direction. ,
A cooling unit for liquefying a substance in a vaporized state in the tubular member is arranged on the upper side in the vertical direction of the tubular member, and the tubular member is a hydrogen generator or a hydrogen storage body before the reaction. A hydrogen generator or a hydrogen storage body, which is arranged between a first tank provided and a second tank for collecting a substance produced by a dehydrogenation reaction or a hydrogen addition reaction, and which is provided in the first tank Is sent to the second tank side through the tubular member, the hydrogen generator or hydrogen storage body contacts the catalyst and vaporizes during the passage, and the vaporized substance is cooled by the cooling unit. It is characterized in that it is configured to perform a dehydrogenation reaction or a hydrogen addition reaction with respect to a hydrogen generating body or a hydrogen storing body by repeating the operation of liquefying and further liquefying the material to contact the catalyst and vaporize again. .

According to the above-mentioned invention, the catalyst for carrying out the dehydrogenation reaction or the hydrogenation reaction is arranged on the lower inner surface of the tubular member, and the vaporized substance is cooled on the upper side of the tubular member. A cooling unit that liquefies is arranged. Then, the hydrogen generator or the hydrogen storage body passes through the tubular member while repeating vaporization and liquefaction. Therefore, the hydrogen generating body or the hydrogen storing body passing through the narrow tubular member is surely brought into contact with the catalyst to cause the dehydrogenation reaction or the hydrogen addition reaction, and the efficiency of the reaction is enhanced.

According to another aspect of the invention, in the above hydrogen generating / storing device, the cooling part is a pipe for circulating the refrigerant generated by the cooling device, and is adjacent to the upper surface in the vertical direction of the tubular member. It is characterized in that it is composed of a pipe that is formed.
Therefore, the cooling unit is always efficiently cooled by the circulating refrigerant.

According to another aspect of the invention, in the above hydrogen generating / storing device, the tubular member has alternating gradients of rising and descending from the first tank side toward the second tank side. It is characterized by being arranged in a zigzag pattern. Therefore, by utilizing the zigzag gradient, it becomes easier for the hydrogen generator or hydrogen store to come into contact with the catalyst. As a result, the reaction efficiency becomes higher.

In another aspect of the present invention, in the above hydrogen generating / storing device, heating for heating a catalyst to a predetermined temperature below the tubular member in the vertical direction to cause a dehydrogenation reaction or a hydrogen addition reaction. The feature is that the device is arranged. Therefore, when the catalyst heated to a predetermined temperature by the heating device comes into contact with the hydrogen generator or the hydrogen storage body,
It will surely cause a hydrogen reaction.

Further, in another invention, in the above hydrogen generating / storing device, a heating device for vaporizing the hydrogen generating body or the hydrogen storing body in the first tank is provided between the first tank and the tubular member. The arrangement is such that the hydrogen generator or the hydrogen storage body is sent into the tubular member in a vaporized state.

Another aspect of the present invention is the above hydrogen generating / storing apparatus, wherein a blower means is provided on the first tank side, and the substance in the tubular member is sent to the second tank side by this blower means. It is characterized by being configured. Therefore, the substance that has undergone the dehydrogenation reaction or the hydrogenation reaction moves more reliably from the first tank side toward the second tank side.

In another aspect of the present invention, in the hydrogen generating / storing apparatus described above, the temperature of the side of the tubular member closer to the first tank is higher than the temperature of the side closer to the second tank. Is characterized in that a temperature gradient is provided. According to this structure, the substance in the vaporized state generated by the dehydrogenation reaction or the hydrogen addition reaction can be surely cooled and liquefied, and can be more efficiently recovered in the second tank.

Another aspect of the present invention is the above hydrogen generating / storing apparatus, wherein the aromatic compound is benzene, toluene,
It is characterized in that any one of xylene, mesitylene, naphthalene, methylnaphthalene, anthracene, biphenyl, phenanthrene, and alkyl-substituted compounds thereof or a mixture of a plurality of them is mixed.

These raw materials store hydrogen by adding hydrogen to carbon-carbon double bonds. The hydrogen supplier after hydrogenation releases hydrogen and returns to the original hydrogen storage body.
That is, the above-mentioned raw material is a raw material suitable for recycling hydrogen. On the other hand, the catalysts used in the hydrogenation reaction of the above-mentioned raw materials have already been researched and developed and are well known. Therefore, if the above-mentioned raw materials are used, the development cost can be suppressed for practical use.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a hydrogen generating / storing device according to the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram for explaining a mechanism common to each embodiment described below. In particular,
It is a figure which shows the principle which stores or supplies hydrogen using the hydrogenation reaction of an aromatic compound, and the dehydrogenation reaction of the compound (henceforth a chemical hydride) produced | generated by the hydrogenation reaction of the aromatic compound.

The aromatic compound 1 such as benzene undergoes a hydrogenation reaction with hydrogen 2 produced by electrolysis of water to become a chemical hydride 3 such as cyclohexane. Specifically, hydrogen 2 is added to the carbon-carbon double bond of the aromatic compound 1. That is, hydrogen 2 is chemical hydride 3
Will be stored in the form of.

Further, the chemical hydride 3 becomes an aromatic compound 1 and hydrogen 2 by the dehydrogenation reaction. The hydrogen 2 thus generated is supplied to the fuel cell 5 together with the oxygen 4. This fuel cell 5 produces electricity by the reverse principle of electrolysis of water.

As described above, the aromatic compound 1 functions as a hydrogen storage body capable of storing hydrogen 2, and the chemical hydride 3 functions as a hydrogen generator generating hydrogen 2. Therefore, it is possible to form a hydrogen generation / storage system using the cycle of the aromatic compound 1 and the chemical hydride 3.

Next, an example of a hydrogen generation / storage system using the principle shown in FIG. 1 will be described with reference to FIG. In the following, the raw materials such as chemical hydride will not be numbered. Further, the hydrogen generation / storage device 14 which is a part of the hydrogen generation / storage system shown in FIG. 2 is a device according to the embodiment of the present invention.

FIG. 2 is a diagram schematically showing a hydrogen storage / supply system, which is an example of energy self-sustaining home power generation for home use. The hydrogen generation / storage device of the present invention functions as a part of this system. FIG. 3 is a diagram showing the structure of the hydrogen generation / storage device 14 according to the embodiment of the present invention.

The hydrogen storage / supply system provided in the house 10 mainly includes a solar cell 11 installed on a roof, a wind power generator 12, an electrolysis device 13, and a hydrogen generation / storage device 14.
And a fuel cell 15.

The hydrogen generating / storing device 14 generates hydrogen by utilizing the dehydrogenation reaction of chemical hydride represented by cyclohexane, which is a hydrogen generating substance which releases hydrogen and changes to an aromatic compound, and generates this hydrogen. It can be sent to the outside of the hydrogen generation / storage device 14. Further, the hydrogen generation / storage device 14 is capable of causing an aromatic compound represented by benzene to react with hydrogen and storing hydrogen in the hydrogen generation / storage device 14.

As shown in FIG. 3, the hydrogen generating / storing device 1
4 is a substance supply tank (hereinafter, referred to as a first tank) 16 including a chemical hydride serving as a hydrogen generating body before reaction or an aromatic compound serving as a hydrogen storing body, and dehydrating the hydrogen generating body or the hydrogen storing body. A tilted zigzag tubular member 17 serving as a reaction member for causing an elementary reaction or a hydrogen addition reaction, and a substance storage tank for recovering a substance generated by the dehydrogenation reaction or the hydrogen addition reaction (hereinafter, Second tank) 18). Then, the hydrogen generating body or the hydrogen storing body in the first tank 16 is passed through the tubular member 17 and sent to the second tank 18 side, so that the dehydrogenation reaction or the hydrogen addition is performed in the tubular member 17. A reaction is generated and the substance after the reaction is stored in the second tank 18.

Pipes 16a1 and 16a2 and a pump 19 are disposed between the first tank 16 and one end of the tubular member 17. That is, the first tank 16 is arranged at one end of the pipe 16a1, and the hydrogen generating body or the hydrogen storage body in the first tank 16 is sucked up at the other end to make the tubular member 17
A pump 19 is provided for feeding the side. A hydrogen inlet 16b is provided in a portion of the pipe 16a2 between the pump 19 and one end of the tubular member 17 so as to communicate with the tubular 16a2. This hydrogen inlet 16b
Is for inputting hydrogen in the hydrogenation reaction of an aromatic compound such as benzene with hydrogen, and is connected to the electrolysis device 13 described above. Therefore, the electrolytic device 1
The hydrogen generated in 3 is fed into the tubular member 17 through the hydrogen inlet 16b.

The tubular member 17 has a zigzag shape. That is, the tubular member 17 has a slope 17a that rises from the first tank 16 side toward the second tank 18 side.
And a gradient 17b descending from the first tank 16 side toward the second tank 18 side are alternately provided. Although the tubular member 17 has a quadrangular cross section, it may have a circular cross section, an elliptical cross section, or a hexagonal cross section.

This tubular member 17 is, as shown in FIG.
It is arranged in a tilted state (horizontal state in this embodiment). In this embodiment, the tubular member 17 is installed in a completely horizontal state, but it may be tilted with the second tank 18 side tilted upward or downward as a whole. A catalyst 20 for dehydrogenating or hydrogenating a hydrogen generator or a hydrogen storage body is arranged on the inner surface of the tubular member 17 in the tilted state on the lower side in the vertical direction. As the catalyst 20, an active carbon material on which a platinum catalyst is supported is used.

Further, on the outer surface of the tubular member 17 on which the catalyst 20 is disposed, that is, the outer surface on the lower side in the vertical direction, the catalyst 20 is set at a predetermined constant temperature suitable for the dehydrogenation reaction or the hydrogenation reaction. A heater 21 that serves as a heating device is provided. Usually, the catalyst 20 is always kept at 250 to 400 ° C. by the heater 21. First mentioned above
The hydrogen generator or the hydrogen storage in the tank 16 is sucked up by the pump 19 and sent into the tubular member 17, so that the hydrogen generator or the hydrogen storage is a liquid film on the surface of the heated catalyst 20. Contact so that
A dehydrogenation reaction or a hydrogenation reaction occurs.

The amount of hydrogen generator or hydrogen storage material sent into the tubular member 17 by the pump 19 is determined by the tubular member 17
Of hydrogen generator or hydrogen storage over the entire length, that is, the amount that substantially fills the inside of the tubular member 17, or only slightly, specifically, the first rising slope and the first descending slope. The liquid film state may be formed only in the area. The dehydrogenation reaction or hydrogenation reaction proceeds in the tubular member 17 by repeating vaporization and liquefaction even if the amount of the hydrogen generator or the hydrogen storage body is very small, and the reacted substance is gradually added to the second tank 18 side. Sent to. When the vapor does not move to the second tank 18 side when vaporized, an air blowing unit is provided on the first member 16 side of the tubular member 17, and the air is blown by the air blowing unit to generate the second air. The vaporized vapor may be moved to the tank 18 side.

Further, the cylindrical member 17 in the tilted state
A cooling unit 22 for liquefying the vaporized substance in the tubular member 17 is disposed on the upper side in the vertical direction of the. The cooling unit 22 is configured by a pipe that circulates a coolant such as cold water or air generated by the cooling device 23. The cooling unit 22 is arranged adjacent to the upper portion of the tubular member 17.

The cooling unit 22 is the tubular member 1 as described above.
When the hydrogen generator or hydrogen storage sent into 7 contacts the catalyst 20 and is vaporized by dehydrogenation reaction or hydrogen addition reaction, the vaporized substance is cooled to be liquefied. . The liquefied substance falls and touches the catalyst 20 arranged in the lower part. Then, as described above, the dehydrogenation reaction or the hydrogenation reaction is performed again to vaporize. The vaporized substance is cooled by the cooling unit 22 and liquefied again. In this way, when the substance in the first tank 16 is sent to the tubular member 17, the tubular member 1
Second tank 18 while repeating vaporization and liquefaction in 7
Move to the side.

The other end of the tubular member 17 and the second tank 18 are connected by a pipe 18a. A hydrogen discharge port 18b is connected to an intermediate portion of the pipe 18a. The hydrogen discharge port 18b is for sending the hydrogen generated by the dehydrogenation reaction from the hydrogen generation / storage device 14 to the fuel cell 15, and is connected to the fuel cell 15 described above.
Thus, the hydrogen generated by the hydrogen generation / storage device 14 is sent to the fuel cell 15 from the hydrogen discharge port 18b.

Below, an explanation will be given of an operation example when hydrogen is generated by the hydrogen generating / storing device 14 described above.

First, the hydrogen inlet 16b is closed by a valve (not shown). Next, the hydrogen generator made of chemical hydride such as cyclohexane or decalin contained in the first tank 16 is sucked up by the pump 19 and sent to the tubular member 17. As a result, the hydrogen generator penetrates into the tubular member 17, contacts the catalyst 20, and a dehydrogenation reaction occurs. As described above, the catalyst 20 is heated by the heater 21 at a temperature between 250 ° C. and 400 ° C.
It is kept at a constant temperature.

By the dehydrogenation reaction, the hydrogen generating material which comes into contact with the catalyst 20 heated in this way becomes benzene and hydrogen in the case of cyclohexane and naphthalene and hydrogen in the case of decalin. Benzene and naphthalene, which are hydrogen storage bodies vaporized by the dehydrogenation reaction, are cooled and liquefied by the cooling unit 22 arranged on the upper side of the tubular member 17.
Then, the liquefied hydrogen storage body is gradually sent to the second tank 18 side while repeating vaporization and liquefaction. Further, when the catalyst 20 is touched, the vaporized cyclohexane and decalin that have been vaporized as they are without undergoing a dehydrogenation reaction are cooled and liquefied by the cooling unit 22 and fall to contact the catalyst 20 again.

As a result, a dehydrogenation reaction occurs, but the hydrogen generators such as cyclohexane and decalin that have not undergone dehydrogenation also vaporize, and are cooled and liquefied by the cooling unit 22 to fall and touch the catalyst 20 again. In the tubular member 17, the hydrogen generating body gradually undergoes a dehydrogenation reaction while repeating vaporization and liquefaction in this way, and almost near the outlet of the tubular member 17 (near the end on the second tank 18 side). All hydrogen generators undergo dehydrogenation. That is, when the hydrogen generator is cyclohexane, it is separated into benzene and hydrogen, and when it is decalin, it is separated into almost 100% into naphthalene and hydrogen.

That is, the hydrogen generator becomes an aromatic compound which is a hydrogen storage body while generating hydrogen. Aromatic compounds such as benzene and naphthalene and hydrogen are
8a. Here, the aromatic compound is stored in the second tank 18 through the pipe 18a. On the other hand, hydrogen is
It is sent to the fuel cell 15 through the hydrogen discharge port 18b connected to the pipe 18a.

Next, an operation example when hydrogen is stored by the hydrogen generation / storage device 14 will be described.

First, the hydrogen storage is put in the first tank 16. Next, the hydrogen outlet 18b is closed by a valve (not shown), while the valve (not shown) of the hydrogen inlet 16b is opened to bring the electrolysis device 13 and the pipe 16a2 of the hydrogen generation / storage device 14 into communication with each other. Throw in. Next, the hydrogen storage made of an aromatic compound such as benzene or naphthalene contained in the first tank 16 is sucked up by the pump 19 and sent to the tubular member 17. As a result, the hydrogen storage body penetrates into the tubular member 17, and the catalyst 2
Touch 0 to cause hydrogenation reaction. The catalyst 20 is
As mentioned above, between 250 ° C and 400 ° C,
It is kept at a constant temperature.

By the reaction with hydrogen, the hydrogen storage material applied to the thus heated catalyst 20 becomes, for example, cyclohexane in the case of benzene and hydrogen and decalin in the case of naphthalene and hydrogen. Cyclohexane and decalin that have been vaporized by the hydrogenation reaction are
It is cooled and liquefied by the cooling unit 22 arranged on the upper part of 7. Then, the liquefied hydrogen generator is gradually sent to the second tank 18 side while repeating vaporization and liquefaction. Further, the hydrogen storage body such as benzene and naphthalene in a vaporized state which has been vaporized as it is without undergoing a hydrogen addition reaction when touching the catalyst 20 is cooled by the cooling unit 22 and is liquefied and falls to fall again on the catalyst 20. Touch.

As a result, a hydrogen addition reaction occurs,
The hydrogen storage body such as benzene and naphthalene that has not undergone the hydrogenation reaction is also vaporized, cooled by the cooling unit 22 and liquefied, and falls and touches the catalyst 20 again. In the tubular member 17, the hydrogen storage body gradually undergoes a hydrogenation reaction while repeating vaporization and liquefaction in this way, and almost near the outlet of the tubular member 17 (near the end on the second tank 18 side). All hydrogen storage bodies undergo hydrogenation reaction to become hydrogen generators. That is, when the hydrogen store is benzene, it becomes cyclohexane, and when it is naphthalene, it becomes decalin.

The hydrogen generator composed of chemical hydride such as cyclohexane or decalin is sent to the pipe 18a in a liquid state and stored in the second tank 18 through the pipe 18a.

Next, an energy self-sustaining home private power generation system using the hydrogen generation / storage system using the hydrogen generation / storage device 14 will be described.

As shown in FIG. 2, electricity generated by the solar cell 11 or the wind power generator 12 is supplied to the inverter 24.
Is converted to alternating current via. The converted electricity is used for household electric appliances 25, or when the electric appliances 25 are not used, the converted electricity is electrolyzed.
Is supplied to. In the electrolyzer 13, hydrogen (H2) and oxygen (O2) are generated by electrolysis of water. The generated hydrogen is sent to the cylindrical member 17 from the hydrogen inlet 16b.

It should be noted that hydrogen is generated by utilizing the hydrogen addition reaction.
When storing hydrogen in the storage device 14, the valve of the hydrogen inlet 16b is opened to introduce hydrogen into the tubular member 17, and the valve of the hydrogen outlet 18b is closed. On the other hand, when hydrogen is generated in the hydrogen generation / storage device 14 using the dehydrogenation reaction, the valve of the above-described hydrogen charging port 16b is closed, and hydrogen is not charged into the tubular member 17, The valve of the hydrogen discharge port 18b is opened. As a result, the hydrogen generation / storage device 14 and the fuel cell 15 are brought into communication with each other.

Even when the electricity produced by the solar cell 11 or the wind power generator 12 is excessive, that is, when electricity is generated more than the electricity used by the household electric appliance 25, the extra electricity is It is sent to the electrolysis device 13. Then, the hydrogen generated in the electrolysis device 13 is sent to the cylindrical member 17 side of the hydrogen generation / storage device 14. Also in this case, when hydrogen is stored, the hydrogen charging port 16b is used.
Is opened to supply hydrogen to the hydrogen generation / storage device 14,
When performing the dehydrogenation reaction, hydrogen is not introduced into the cylindrical member 17 because the valve of the hydrogen inlet 16b is closed.

When hydrogen is sent from the electrolysis device 13 to the hydrogen generation / storing device 14 and hydrogen is stored in the hydrogen generation / storing device 14 by a hydrogen addition reaction, an aromatic compound represented by benzene sucked from the first tank 16 The hydrogen storage body made of a compound is fed into the cylindrical member 17. On the other hand, hydrogen inlet 1
Hydrogen is introduced from 6b.

Then, an exothermic reaction starts, hydrogen is added to the hydrogen storage body, and the hydrogen storage body is changed to a hydrogen generation body composed of chemical hydride represented by cyclohexane. The hydrogen generator is cooled in the tubular member 17 by the cooling unit 22 adjacent to the tubular member 17 and liquefied, and then stored in the second tank 18 through the pipe 18a. That is, the hydrogen storage body is added with hydrogen and undergoes a hydrogenation reaction to become a hydrogen generation body, which is stored in the second tank 18.

Further, the solar cell 11 or the wind power generator 12
In the case where the electricity generated by the above cannot supply the electric power of the electric device 25, the hydrogen generator stored in the second tank 18 which is previously transferred to the first tank 16 is sucked in as described above. It is then supplied into the tubular member 17. As a result, a dehydrogenation reaction occurs in the tubular member 17, and the hydrogen generated by this dehydrogenation reaction is supplied to the fuel cell 15 from the hydrogen discharge port 18b. In addition, when the hydrogen generator recovered in the second tank 18 is moved to the first tank 16, when the hydrogen generator is recovered, it is transferred to another storage device to generate electricity. It is preferable that the first tank 16 is automatically supplied from the storage device.

That is, when hydrogen is generated in the hydrogen generation / storage device 14, the hydrogen inlet 16b is closed by a valve (not shown). Then, in this state, the hydrogen generator is supplied to the cylindrical member 17.

Then, the hydrogen generator comes into contact with the catalyst 20 set to a predetermined temperature by the heating device, and the catalyst 2
The surface of 0 becomes a liquid film state. That is, the dehydrogenation reaction is likely to occur. Therefore, the hydrogen generator changes to hydrogen and a hydrogen storage body composed of an aromatic compound represented by benzene. The liquid hydrogen storage body flows to the second tank 18 side in the tubular member 17 by the force of the pump 19 or the like, and passes through the pipe 18a in the liquid state to the second tank 18 side.
Sent to and stored. Hydrogen is sent to the fuel cell 15 through the hydrogen outlet 18b.

In the fuel cell 15, the hydrogen generating / storing device 1
Electricity is produced by the reaction between hydrogen sent from No. 4 and oxygen supplied from the air. The electricity thus generated is used not only for household electric appliances 25 but also for powering an electric vehicle 26. In this way, the hydrogen generation / storage device 14 stores energy in the form of a hydrogen generator such as cyclohexane, or produces energy from the hydrogen generator by a dehydrogenation reaction, according to the demand for electric power at home. .

In the hydrogen generation / storage device 14 which is a part of the hydrogen storage / supply system of FIG. 2, the hydrogen storage body is not toluene, xylene, mesitylene, methylnaphthalene, anthracene, biphenyl, instead of benzene or naphthalene. Any one or a plurality of phenalenes and their alkyl-substituted compounds may be used in combination.

Next, a control unit for performing various controls of the hydrogen generation / storage device 14 of the above-described embodiment will be described.

As shown in FIG. 4, the control unit 60 mainly
A control panel 61, a CRT monitor 62, an operation unit 63 such as a keyboard and a mouse, a personal computer body 64, a P
The CI expansion unit 65 is provided to perform various controls.

The control panel 61 includes a power switch 70 for a 100V power source, a power switch 71 for a 200V power source for a pump, a flow meter 72 for measuring the flow rate of hydrogen discharged to the outside, and a flow rate of hydrogen taken in from the outside. A flow meter 73 for measuring and a temperature controller 7 for controlling the temperature inside the tubular member 17.
4, an alarm section 81 by a buzzer, and an operation switch 82
And a status indicator lamp 83 for displaying the operating status.

The control unit 60 is turned on by the temperature of the catalyst 20, the temperature of the inner space of the tubular member 17, the temperature of the surface of the heater 21 serving as a heating device, the temperature of each raw material, the temperature of the surface of the cooling unit 22. Controls the temperature of hydrogen. In addition, the control unit 60
Measures the flow rate of hydrogen that is generated and the flow rate of hydrogen that is input into the device.

The control unit 60 also detects the hydrogen pressure after cooling and the pressure of hydrogen introduced into the apparatus. Further, the control unit 60 is configured to be able to set the upper limit and the lower limit of the liquid level of the first tank 16, and also has a mechanism for notifying the liquid level when there is no liquid level between the upper limit and the lower limit.

The personal computer main body 64 is a portion for setting and controlling the temperature, pressure and the like in various components of the tubular member 17, and at the same time, can analyze hydrogen by the installed analysis software of gas chromatography.

Next, the result of grasping the operating conditions with a lab-scale device before the operation of the hydrogen generation / storage device 14 will be described.

FIG. 5 is a graph showing the results of examining the reaction temperature dependence of the dehydrogenation reaction of cyclohexane. The horizontal axis is the reaction temperature, and the vertical axis is the hydrogen generation rate per minute. As shown in FIG. 5, when the reaction temperature is 523 K (= 250 ° C.),
It can be seen that the amount of hydrogen generated is the largest. Moreover, when the reaction temperature is too high, the amount of hydrogen generated decreases. It is considered that this is because the volatile content of the raw material increases and it becomes difficult to form a liquid film of the raw material on the surface of the catalyst 20.

FIG. 6 is a graph showing the results of examining the group mass dependence of the dehydrogenation reaction of cyclohexane. The horizontal axis is the basic mass, and the vertical axis is the hydrogen generation amount per minute. Here, the base mass is the supply amount of cyclohexane. Catalyst 2
For 0, 0.5 g of platinum was used. The reaction temperature is 52
It was set to 3K.

As shown in FIG. 6, it is understood that the hydrogen generation amount is the largest when the cyclohexane supply amount is 1.7 ml. It is considered that the increase in the amount of cyclohexane supplied decreases the amount of hydrogen generation because the catalyst 20 was exposed to more cyclohexane than necessary and an appropriate liquid film could not be formed on the catalyst surface.

The above is the result of an experiment conducted for investigating the dehydrogenation reaction conditions of cyclohexane, but chemical hydride such as decalin can be used in addition to cyclohexane. Next, the lab-scale experimental results using decalin will be described.

FIG. 7 is a diagram showing a reversible reaction formula in which naphthalene and hydrogen are produced by the dehydrogenation reaction of decalin and conversely decalin is produced by the hydrogenation reaction of naphthalene. Even when decalin is used, only hydrogen can be generated without breaking the carbon skeleton, as in the case of using cyclohexane. Therefore, decalin can be a clean energy source that can prevent global warming associated with carbon dioxide emission.

FIG. 8 is a graph showing the results of examining the group mass dependence of the dehydrogenation reaction of decalin. The horizontal axis is the basic mass, and the vertical axis is the hydrogen generation amount per minute. Here, the base mass is the supply amount of decalin. 0.
5 g of platinum was used. The reaction temperature was 523K.

As shown in FIG. 8, it is understood that the hydrogen generation amount decreases as the supply amount of decalin increases from 1.4 to 1.75 ml. It is considered that the reason why the hydrogen generation amount decreases when the supply amount of decalin is increased is that the catalyst 20 was applied with more decalin than necessary and a proper liquid film could not be formed on the catalyst surface.

FIG. 9 is a graph showing the results of comparing the amount of hydrogen generated by changing the type of chemical hydride.
In the figure, open triangles indicate the case where only decalin was used. The black diamonds show the case of using a mixed solution of decalin and methylcyclohexane, and the black squares show the case of using a mixed solution of decalin and cyclohexane.
The amount of hydrogen gas generated is shown as a cumulative value for each hour. The reaction temperature was 573K, and the amount of raw material supplied was 1.
It was set to 75 ml / min.

As a result, it was found that when only decalin was dehydrogenated, hydrogen gas was extremely generated. It was also found that the hydrogen gas generation amount was the smallest in the case of a mixed liquid of decalin and methylcyclohexane. It should be noted that naphthalene produced by dehydrogenation of decalin has a high melting point (about 80 ° C.) and is difficult to use at room temperature. Therefore, it is preferable to use cyclohexane rather than decalin.

[0078]

[Table 1]

Table 1 is a table showing the results of hydrogen release using various chemical hydrides. As the chemical hydride, methylcyclohexane can be used in addition to cyclohexane or decalin. In addition, as other compounds containing hydrogen, methanol, lithium hydride and calcium hydride can also be used. Judging only from the amount of hydrogen generation (= weight of hydrogen generated for the same weight of raw material), lithium hydride, decalin, and cyclohexane have superiority as raw materials.

However, in terms of the ease of use of the raw material after releasing hydrogen, decalin which produces naphthalene is inferior to cyclohexane. This is because naphthalene becomes solid at room temperature and sublimates without liquefying at 80 ° C or higher. Further, lithium hydride is inferior to cyclohexane in terms of handling danger. Cyclohexane becomes benzene after the dehydrogenation reaction. Benzene has a boiling point of 80.1 ° C., which is an easy-to-use raw material like cyclohexane having almost the same boiling point. Therefore, cyclohexane is the most suitable raw material from the viewpoint of ease of use including hydrogen release and safety.

However, raw materials other than cyclohexane can be used by improving the safety and changing the use conditions. For example, a chemical hydride that becomes xylene, mesitylene, methylnaphthalene, anthracene, biphenyl, or phenathrene after releasing hydrogen can be used.

The type of catalyst used in the reaction was also examined. Specifically, platinum, platinum mixed with 4.5 wt% tungsten, and platinum mixed with 1.9 wt% rhodium were examined. As a result, it was found that the amount of hydrogen generated was maximum when a platinum catalyst containing 4.5 wt% tungsten was used.

The present invention is not limited to the above embodiment. For example, in the above-described embodiment, the system and the apparatus including both the hydrogenation reaction and the dehydrogenation reaction have been described, but the apparatus and the system that perform only one of the reactions and the apparatus that performs the other reaction are described. The system may be configured as another system. When the apparatus is configured to perform either one, it is not necessary to provide an unnecessary one of the hydrogen inlet 16b and the hydrogen outlet 18b that is closed by the valve as described above. That is, when the device used only for the operation of generating hydrogen is configured so as to have the hydrogen discharge port 18b and not the hydrogen input port 16b, and when the device is used only for the operation of storing hydrogen, The hydrogen inlet 16b may be provided but the hydrogen outlet 18b may not be provided.

Further, in the above-described embodiment, hydrogen generation /
Although the tubular member 17 serving as a reaction member of the storage device 14 has a zigzag structure, the tubular member 17 may have a meandering shape or a straight shape. Also, the hydrogen outlet 18
A filter such as activated carbon may be added in the vicinity of b to surely prevent the hydrogen storage body from being introduced into the fuel cell 15 side through the hydrogen discharge port 18b.

Further, in the above embodiment, the tubular member 1
The temperature of the catalyst 20 is kept constant by arranging a heater 21 serving as a heating device on the outer peripheral portion of the lower part of 7. In addition, in the above-described embodiment, the inlet portion (first tank 16 side) and the outlet portion (second tank 18 side) of the tubular member 17 and the intermediate portion thereof are set to substantially the same temperature. . However, the temperature inside the tubular member 17 is higher on the first tank 16 side and higher on the second tank 18 side.
A temperature gradient may be provided so that the temperature becomes lower on the side.

In this case, if the temperature gradient is provided in the tubular member 17 by controlling the set temperature of the heater 21, the cooling unit 22 does not need to be specially temperature controlled. Regarding the above, the second tank 18 side is lowered, which is preferable. In addition, the second tank 18
The temperature gradient may be such that the side becomes lower. Also, the second
The temperature gradient that lowers the temperature of the tank 18 side of the heater is achieved by controlling the set temperature of the cooling device 23 side.
1 and the cooling unit 22 are provided with a temperature gradient. When the temperature on the second tank 18 side is lowered as described above, the liquefaction of the vaporized substance on the second tank 18 side becomes more efficient, and the dehydrogenation reaction or the hydrogenation reaction becomes more efficient. It can be done reliably.

Further, in the above embodiment, the pump 19
The hydrogen generator or the hydrogen storage body is sucked in liquid form from the first tank 16 and supplied to the tubular member 17, and the substance is sent to the second tank 18 side while repeating vaporization and liquefaction by the tubular member 17. Although configured, the first tank 1
A heating device for vaporizing the hydrogen generating body or the hydrogen storing body in the first tank 16 is arranged between the cylindrical member 6 and the cylindrical member 17, and the hydrogen generating body or the hydrogen storing body is vaporized to form a cylinder. You may make it supply to the linear member 17.

Further, in the above embodiment, the tubular member 1
The catalyst 20, the heater 21, and the cooling unit 22 are arranged over the entire length of 7, but they may be provided only in the ascending slope 17a portion, or may be provided only in the descending slope 17b portion. Catalyst 20, heater 2
1, the cooling unit 22 may be arranged in an appropriate combination. Further, the tubular members 17 may be provided in a plurality of rows. That is, a plurality of tubular members 17 may be provided in parallel for one first tank 16 and one second tank 18, or a plurality of first tanks 16 and a plurality of tubular members may be provided. 17
Alternatively, one second tank 18 may be provided, or conversely, a plurality of tubular members and a plurality of second tanks 18 may be provided for the first tank 16. good.

Further, in the above-described embodiment, an example in which hydrogen is supplied to the fuel cell has been described, but a power generator other than the fuel cell may be adopted. For example, hydrogen may be burned to boil water, and a turbine may be rotated to generate electricity by rotating a generator. Further, this hydrogen storage / supply system may be used in combination with an electric power supply system such as a conventional thermal power plant or nuclear power plant.

[0090]

According to the present invention, a catalyst and a cooling unit are arranged in a tubular member, and a hydrogen generator or a hydrogen storage body moves while repeating vaporization and liquefaction in the tubular member. As a result, the hydrogen generator or the hydrogen store is surely brought into contact with the catalyst, and the reaction efficiency of the hydrogen addition reaction or dehydrogenation reaction can be increased.

[Brief description of drawings]

FIG. 1 is a diagram showing a principle underlying a hydrogen storage / supply system using a hydrogen generation / storage device of the present invention, which is produced by a hydrogenation reaction of an aromatic compound and a hydrogenation reaction of the aromatic compound. It is a figure which shows the flow which stores or produces | generates hydrogen using the dehydrogenation reaction of a compound (chemical hydride).

FIG. 2 is a diagram showing a hydrogen storage / supply system using the hydrogen generation / storage device according to the embodiment of the present invention, and is a diagram showing a hydrogen storage / supply system using energy self-sustaining home-use private power generation as an example. is there.

FIG. 3 is a schematic diagram showing the structure of the hydrogen generation / storage device of FIG.

4 is a diagram showing a control unit that performs various controls of the hydrogen generation / supply device of FIG.

FIG. 5 is a graph showing the results of examining the reaction temperature dependence of the dehydrogenation reaction of cyclohexane used in the present invention.

FIG. 6 is a graph showing the results of examining the group mass dependence of the dehydrogenation reaction of cyclohexane used in the present invention.

FIG. 7 is a diagram showing a reaction formula in which naphthalene and hydrogen are produced by the dehydrogenation reaction of decalin that can be used in the present invention, and conversely, decalin is produced by the hydrogenation reaction of naphthalene.

FIG. 8 is a graph showing the results of examining the group mass dependence of the dehydrogenation reaction of decalin usable in the present invention.

FIG. 9 is a graph showing the results of comparing the amount of hydrogen generated by changing the type of chemical hydride usable in the present invention.

[Explanation of symbols]

14 Hydrogen generation / storage device 16 First tank 17 Cylindrical member (reaction member) 18 Second tank 20 catalyst 21 Heater (heating device) 22 Cooling unit 23 Cooling device

Claims (8)

[Claims] 1. A dehydrogenation reaction or hydrogen between a hydrogen generator that releases hydrogen to be converted into an aromatic compound and a hydrogen storage material that reacts with the hydrogen to store the hydrogen and is composed of the aromatic compound. A hydrogen generating / storing device for generating or storing hydrogen by using an addition reaction, wherein a tubular member serving as a reaction member for generating the dehydrogenation reaction or the hydrogen addition reaction is arranged in a tilted state. A catalyst for causing the dehydrogenation reaction or the hydrogenation reaction of the hydrogen generator or the hydrogen storage body is arranged on the inner surface of the cylindrical member on the lower side in the vertical direction, and the catalyst is arranged in the vertical direction of the cylindrical member. A cooling unit for liquefying the vaporized substance in the tubular member is arranged on the upper side, and the tubular member includes the hydrogen generator or the hydrogen storage body before the reaction. Tan And a second tank for recovering a substance produced by the dehydrogenation reaction or the hydrogen addition reaction, and the hydrogen generator or the hydrogen storage body provided in the first tank. Is passed through the tubular member and sent to the second tank side, at the time of passing, the hydrogen generator or the hydrogen store contacts the catalyst and is vaporized, and the vaporized substance is cooled by the cooling. Is cooled and liquefied by the section, and the operation of vaporizing the liquefied substance by contacting the catalyst again is repeated to repeat the dehydrogenation reaction or the hydrogenation reaction with respect to the hydrogen generator or the hydrogen storage body. A hydrogen generation / storage device characterized by being configured to perform. 2. The cooling unit is a pipe that circulates a refrigerant generated by a cooling device, and the pipe is adjacent to an upper surface of the tubular member in the up-down direction. The hydrogen generation / storage device according to claim 1. 3. The cylindrical member is configured in a zigzag shape in which both a rising slope and a descending slope are alternately arranged from the first tank side toward the second tank side. The hydrogen generating / storing device according to claim 1 or 2, which is characterized. 4. A heating device for heating the catalyst to a predetermined temperature in order to cause the dehydrogenation reaction or the hydrogenation reaction is disposed below the tubular member in the vertical direction. Item 5. The hydrogen generation / storage device according to any one of items 1 to 3. 5. A heating device for vaporizing the hydrogen generating body or the hydrogen storing body in the first tank is arranged between the first tank and the tubular member, and the hydrogen generating body or the hydrogen generating body is provided. The hydrogen generating / storing device according to any one of claims 1 to 4, wherein the hydrogen storage body is sent into the tubular member in a vaporized state. 6. An air blower is provided on the first tank side,
The hydrogen generating / storing device according to any one of claims 1 to 5, wherein the air blowing means is configured to send the substance in the tubular member to the second tank side. 7. A temperature gradient is provided such that the temperature on the side closer to the first tank in the tubular member is higher than the temperature on the side closer to the second tank. The hydrogen generating / storing device according to any one of claims 1 to 6. 8. A mixture of any one or more of the above aromatic compounds selected from benzene, toluene, xylene, mesitylene, naphthalene, methylnaphthalene, anthracene, biphenyl, phenanthrene and alkyl-substituted compounds thereof. The hydrogen generating / storing device according to any one of claims 1 to 7, wherein: