JP2019099419A - Hydrogen generation system and fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized hydrogen generating system which stably generates hydrogen in a medium temperature range. A hydrogen generator for reforming an aqueous solution of methanol to generate hydrogen, a condensation separator for condensing a hydrogen-containing gas discharged from the hydrogen generator to separate a hydrogen gas and a condensate, and a condenser. Re-supplying means for re-supplying at least unreacted methanol in the product to the hydrogen generator, the hydrogen generator has a tubular structure with at least one end opened, and the heating chamber is provided inside the tubular structure. An arranged base body, a catalyst which is arranged so as to cover at least a part of the outer peripheral surface of the cylindrical structure of the base body, and in which a catalytic metal is carried on a carbon sheet, an exterior material which houses the base body on which the catalyst is arranged, Is arranged at one end side in the length direction of the cylinder, and is arranged at the discharge port for discharging hydrogen gas and the other end side in the cylinder length direction of the base body, and the aqueous methanol solution is placed between the base body and the exterior material. And a supply port for supplying the hydrogen. [Selection diagram] Figure 1

Description

  The present disclosure relates to a hydrogen generation system and a fuel cell system.

  Methanol, which is a clean energy source, has attracted attention as a hydrogen source in that it has a large amount of hydrogen generated by the reforming reaction. As one of the applications of a hydrogen supply source, a fuel cell that has been attracting attention in recent years is required to have a method for producing hydrogen of particularly high purity for practical use.

The reforming of methanol is generally known by vapor phase catalytic steam reforming. In the steam reforming method, a copper catalyst or a composite catalyst obtained by adding a second metal such as zinc to copper is used.
However, since the steam reforming method is a solid-gas contact method, it is necessary to prepare an evaporation heat for converting methanol and water into a gas in advance and a wide solid-gas contact area in the endothermic reactor, so It is not preferable from the viewpoint of system integration and system downsizing.

On the other hand, there is disclosed a method of producing hydrogen in which a methanol aqueous solution is reformed in a liquid phase in the presence of a solid catalyst (see, for example, Patent Document 1).
Moreover, applying a superheated liquid film type dehydrogenation reaction utilizing a superheated liquid film state as a reforming reaction of a methanol aqueous solution is also disclosed (see, for example, Patent Document 2).

Japanese Patent Application Laid-Open No. 11-157803 Patent No. 4213952

  As mentioned above, although the method of reforming methanol aqueous solution by the liquid phase conventionally is disclosed, even if it is going to reform methanol in the liquid phase simply using a catalyst, high hydrogen conversion can not be expected, Unless a large reaction site is secured, it is difficult to secure a desired amount of hydrogen in a temperature range of about 250 ° C. to 350 ° C.

  It is also desirable to form a superheated liquid film state in liquid phase catalysis in order to increase the hydrogen conversion while carrying out the reforming reaction in a temperature range of about 250 ° C to 350 ° C to suppress CO formation low. It is difficult to maintain the superheated liquid film state at the actual reaction site.

The present disclosure has been made in view of the above.
An object of the present disclosure is to provide a small-sized hydrogen generation system that stably generates hydrogen in a medium temperature range (250 ° C. to 350 ° C.), and a fuel cell system capable of supplying electric power according to demand. Do.

In order to achieve the above object, a hydrogen generation system according to a first aspect of the present disclosure is:
<1> A hydrogen generator for producing a hydrogen gas by reforming an aqueous solution of methanol solution, and a mixed gas containing hydrogen discharged from the hydrogen generator are supplied, and the supplied gas is condensed to at least hydrogen gas The condensation separation device for separating from the condensate, and the resupply means for resupplying to the hydrogen generation device and subjecting to at least aqueous solution reforming the at least unreacted methanol in the condensate separated by the condensation separation device;
The hydrogen generator is
A base having a cylindrical structure in which at least one end is open, and in which the heating chamber is disposed inside the cylindrical structure;
A catalyst which is disposed so as to cover at least a part of the outer peripheral surface of the cylindrical structure of the substrate, and in which a catalyst metal is supported on a carbon sheet;
An exterior material that accommodates the base on which the catalyst is disposed;
A discharge port disposed on the side of the one end in the longitudinal direction of the cylinder of the substrate and discharging hydrogen gas;
A supply port disposed on the side of the other end in the longitudinal direction of the cylinder of the substrate, for supplying a methanol aqueous solution between the substrate and the sheathing material;
And reforming the supplied aqueous methanol solution with the catalyst to produce hydrogen gas.

In the hydrogen generation system according to the first aspect, an aqueous solution of methanol is reformed in an aqueous solution by a hydrogen generator equipped with a sheet-like catalyst, and a mixed gas containing reformed hydrogen is condensed by a condensation / separation device. Is separated into at least hydrogen gas and condensate, and the separated hydrogen gas (preferably hydrogen gas purified from a gas phase component other than hydrogen gas by a hydrogen separation membrane etc.) is supplied to an external hydrogen using device . On the other hand, the separated condensate contains unreacted methanol aqueous solution which has not been subjected to the aqueous solution reforming reaction, and at least unreacted methanol among the liquid phase condensate discharged from the condensing separator. Is supplied to the same or another hydrogen generator by the resupply means and subjected to aqueous solution reforming in the hydrogen generator.
Under the present circumstances, the hydrogen generation apparatus makes the space formed between the base | substrate which bears the heating function of a catalyst, and the inner wall of the exterior material which accommodates a base | substrate as a reaction chamber, The cylinder structure of the base | substrate which forms the reaction chamber. In order to cover at least a part of the periphery of the cylindrical structure, a sheet-like catalyst in which a catalyst metal is supported on a heat-conductive sheet-like carrier is arranged, for example, by winding (preferably by winding it several times) The aqueous methanol solution supplied to the reaction chamber is reformed using a sheet catalyst.
That is, the sheet-like catalyst having the catalyst metal supported on the sheet-like support is wound, for example, preferably wound (preferably wound several times) around the cylindrical structure of the base provided with the heating chamber. In addition, the methanol aqueous solution at room temperature is fed from a supply port to a carbon-based sheet-like carrier having heat transferability, capillary condensation is stored in the micropores, and the methanol aqueous solution is heated so as to be preheated to a boiling point there. Set the linear flow velocity. The superheated methanol aqueous solution diffuses and moves on the carbon surface while maintaining a proper wet state to reach the metal particles of the catalyst at the nucleate boiling point. The gas phase product of hydrogen, carbon dioxide and carbon monoxide generated on the surface of the catalytic metal and unreacted methanol aqueous solution form solitary bubbles frequently by making use of the heat source temperature and the good heat flux which greatly exceed the boiling point As soon as the bubbles are released, they are immediately coated with the superheated liquid, and the methanol aqueous solution reforming reaction irreversibly proceeds. Therefore, the endothermic reaction heat and the product desorption heat can be effectively donated to the catalyst as a result of the steep temperature gradient and a large amount of heat transfer, as a result of the densification of the vacant active sites.
As a result, while achieving miniaturization, reformation of hydrogen gas can be performed in an intermediate temperature range (250 ° C. to 350 ° C.), and conversion of the reforming reaction is achieved by circulation reuse of aggregates containing unreacted methanol aqueous solution. The rate will improve dramatically. Further, if the supply rate of the aqueous methanol solution is adjusted, the linear flow rate of the aqueous methanol solution forming the superheated liquid film state is controlled, and the amount of hydrogen meeting the amount of hydrogen required from the fuel cell (external hydrogen demand) While providing the feed, complete conversion of methanol can be achieved throughout the system. Thereby, the amount of generated hydrogen can be dramatically improved.

<2> In the hydrogen generation system according to the first aspect described in <1>, the catalyst is preferably wound around the outer peripheral surface of the substrate to form a laminated structure.
When the catalyst has a laminated structure wound to cover the outer periphery of the substrate heated from the inside of the substrate, bubbles formed in the aqueous methanol solution forming the superheated liquid film state while increasing the amount of supported catalytic metal. Can be released efficiently. As a result, the contact between the catalyst and the gas-liquid mixed phase is minimized, solid-liquid contact can be secured, and the heat transfer coefficient can be kept large. As a result, hydrogen gas can be efficiently obtained while maintaining a state in which film boiling does not occur. Can be generated.

<3> In the hydrogen generation system according to the first aspect described in <1> or <2>, the catalyst has a loading amount of the catalyst metal supported on the carbon sheet of 15 g / L to 150 g / L. Is preferred.
When the supported amount of the catalyst metal supported on the carbon sheet is in the above range, the foaming point in the liquid phase catalytic reaction is increased, the state of nuclear boiling with a large heat transfer coefficient is easily obtained, and the hydrogen gas generation efficiency is improved It becomes.

  <4> In the hydrogen generation system according to the first aspect described in any one of <1> to <3>, the catalyst reforms the supplied aqueous methanol solution in a superheated liquid film state. It is preferred that

By performing the dehydrogenation reaction utilizing the superheated liquid film state, it is possible to further increase the hydrogen gas generation amount.
Here, the "superheated liquid film state" refers to a superheated state (heating at a temperature above the boiling point of methanol) and a state in which the catalyst surface is slightly wet by the aqueous methanol solution.

<5> In the hydrogen generation system according to the first aspect described in any one of <1> to <4>, the aqueous methanol solution supplied from the supply port is in the length direction of the cylinder of the substrate. It is preferable that the catalyst is aqueous solution reformed by being preheated while being circulated and being superheated to a temperature above the boiling point.
By the catalyst temperature being in a high temperature state exceeding the boiling point of methanol, the generation efficiency of hydrogen becomes excellent while suppressing the temperature of the reaction system to a lower level.

<6> In the hydrogen generation system according to the first aspect described in any one of <1> to <5>, the carbon sheet is preferably carbon cloth or carbon felt.
Since both carbon cloth and carbon felt are sheets using fibrous carbon, they have micropores and a large surface area. Therefore, it is easy to hold | maintain the methanol aqueous solution of a superheated state, and it is easy to carry | support a catalyst metal.

<7> In the hydrogen generation system according to the first aspect described in any one of <1> to <6>, the catalyst metal is platinum, palladium, ruthenium, nickel or copper, or platinum, It is preferable that it is a complex of at least one selected from the metal group consisting of palladium, ruthenium, nickel and copper and another metal different from the metal of the metal group.
<8> In the hydrogen generation system according to the first aspect described in <7>, the other metal preferably contains at least one of manganese and zinc.
As described above, by selecting the above-mentioned metal as the catalyst metal, the aqueous solution reforming activity becomes better.

<9> The hydrogen generation system according to the first aspect according to any one of <1> to <8>, wherein the catalyst metal is at least a solid solution containing at least one of platinum, ruthenium and nickel. Is preferred.
As described above, by selecting the above-mentioned metal as the catalyst metal, the aqueous solution reforming activity becomes better.

<10> In the hydrogen generation system according to the first aspect described in any one of <1> to <9>, the catalyst supports metal particles including the catalyst metal, and the metal particles of the metal particles. The average primary particle size is preferably 10 nm or less.
When the catalyst metal is supported as metal particles and the supported metal particles have a small particle diameter, the foaming point in the liquid phase catalytic reaction is increased, the heat conductivity is further improved, and the aqueous solution reforming proceeds more It will be easier.

A fuel cell system according to a second aspect of the present disclosure is
<11> The hydrogen generation system according to any one of <1> to <10>, and a fuel cell that generates electric power using hydrogen gas generated by the hydrogen generation system.

  The fuel cell system according to the second aspect includes the hydrogen generation system according to the first aspect, so the system can be miniaturized, and the outside is maintained while maintaining a medium temperature range of 250 ° C. to 350 ° C. It is possible to supply power according to the demand of the hydrogen using device.

  According to the present disclosure, it is possible to provide a small-sized hydrogen generation system capable of stably generating hydrogen in an intermediate temperature range (250 ° C. to 350 ° C.) and a fuel cell system capable of supplying electric power according to demand.

1 is a schematic configuration view showing an example of a fuel cell system of the present disclosure. 1 is a schematic perspective view showing an example of a hydrogen generator of the present disclosure. It is an exploded view which decomposes | disassembles and shows the hydrogen generator of FIG. It is the sectional view on the AA line of the hydrogen generator of FIG. It is a schematic perspective view which shows the state in which the catalyst is arrange | positioned so that the circumference | surroundings of the cylinder structure of a base | substrate may be covered. It is a schematic perspective view which shows the round catalyst of the single layer structure which supported platinum particle | grains on carbon cloth, a two-layer structure, or a three-layer structure. It is a graph which shows the relationship of the methanol aqueous solution supply rate and hydrogen production rate at the time of making hydrogen production using three types of circular catalysts of FIG. (A) shows a state in which the supply amount of the aqueous methanol solution is too small to dry, (b) shows a film state of a superheated liquid, and (c) shows a suspension state in which the supply amount of the aqueous methanol solution is too large. It is a schematic block diagram which shows another example of the fuel cell system of this indication.

  Hereinafter, embodiments of the hydrogen generation system and the fuel cell system of the present disclosure will be specifically described with reference to FIGS. 1 to 8. However, the present disclosure is not limited to the embodiments described below.

  In one embodiment of the present disclosure, the supplied aqueous methanol solution is reformed with an aqueous solution using a sheet-like catalyst in which platinum particles as a catalyst metal are supported on a sheet-like carbon cloth as a catalyst, and hydrogen gas is generated. Aspects will be described in detail by way of example.

  A fuel cell system 100 according to an embodiment of the present disclosure, as shown in FIG. 1, is a condensation separator that is connected to a hydrogen generator 10 and a hydrogen generator, and is a condensing separator to which a mixed gas containing hydrogen gas is sent. 20, a hydrogen storage tank 30 for storing hydrogen-containing gas separated from condensable methanol and water in the condensation separator 20, and a polymer electrolyte fuel cell (PEFC) which is an example of a fuel cell to which hydrogen gas is supplied And a controller 40 for controlling the system operation.

In a fuel cell system 100 according to an embodiment of the present disclosure, a hydrogen-containing gas is separated in a condensation separator 20 from a mixed gas containing hydrogen generated by aqueous solution reforming in a hydrogen generator 10, and hydrogen is contained through a hydrogen permeable membrane. By supplying hydrogen gas purified from gas to the PEFC, a system for supplying power according to demand from the PEFC to an external hydrogen using device has been constructed. Hydrogen supply according to the demand of PEFC based on external demand can be regulated by flow control of aqueous methanol solution.
In addition, when carbon monoxide is generated by the hydrogen generator, carbon monoxide is temporarily stored as a hydrogen-containing gas together with hydrogen, but is stored as hydrogen is selectively purified from the hydrogen-containing gas. Carbon will increase. And when combustion heat is required, carbon monoxide is provided to combustion and is effectively used as thermal energy.

The hydrogen generator 10 reforms the aqueous solution of methanol supplied from the outside with a catalyst to generate hydrogen gas. The generated hydrogen gas is sent to the condensation separator 20 as a mixed gas mixed with other gas components via the gas discharge pipe 12 connected to the hydrogen generator 10.
Here, the mixed gas discharged from the hydrogen generator contains, in addition to hydrogen generated by the aqueous solution reforming reaction, other gas components such as carbon dioxide, carbon monoxide, water vapor, and unreacted methanol. Therefore, mixed gas containing hydrogen flows through the gas discharge pipe 12 connected to the hydrogen generator.

The hydrogen generator of the present disclosure is further described in detail with reference to FIGS.
One embodiment of the present disclosure includes a hydrogen generator 10 shown in FIG. As shown in FIG. 3, this hydrogen generator 10 has a double structure including a base 13 having a cylindrical structure whose one end is open and the other end is closed, and an exterior material 11 for housing the base 13. It is a cylindrical reforming reactor.
FIG. 2 is a schematic perspective view showing a hydrogen generator according to an embodiment of the present disclosure, and FIG. 3 is an exploded view showing the hydrogen generator 10 of FIG. 2 in an exploded manner.

  The exterior material 11 has a hollow cylindrical structure having one end opened, a discharge port 12a provided on the cylindrical structure for discharging hydrogen gas, and a supply port 14a for supplying an aqueous methanol solution to a hydrogen generator. The discharge port 12a is connected to one end of a gas discharge pipe 12 for discharging a generated gas, and the supply port 14a is connected to one end of a raw material supply pipe 14.

  The gas discharge pipe 12 is a pipe for discharging the gas generated in the reaction chamber of the hydrogen generator 10 to the outside. The other end of the gas discharge pipe 12, as shown in FIG. 1, is connected to a condensation separator 20 for separating hydrogen gas from the mixed gas containing reformed hydrogen gas, and operates the mixed gas pump P1. The mixed gas is sent from the hydrogen generator 10 to the condensing separator 20 through the gas discharge pipe 12.

  The raw material supply pipe 14 includes a raw material supply pump P2, and is a pipe for supplying an aqueous methanol solution, which is a raw material for reforming, to the reaction chamber of the hydrogen generator 10 from the outside. The other end of the raw material supply pipe 14 is connected to a raw material supply device 50 which is a supply source of a methanol aqueous solution as shown in FIG. 1 and supplies raw material from the raw material supply device 50 by operating the raw material supply pump P2. An aqueous methanol solution is supplied to the reaction chamber of the hydrogen generator through a pipe 14.

Although not illustrated, it is preferable that the raw material supply pipe 14 be configured in such a manner that a heater for preheating the methanol aqueous solution is disposed in the middle of the pipe.
When a heater is disposed in the middle of the piping of the raw material supply pipe 14 and the aqueous methanol solution is supplied from the raw material supply pipe 14 to the reaction chamber of the hydrogen generator 10, the methanol aqueous solution is heated to the boiling point in advance before being supplied to the reaction chamber. Preferably. By supplying the aqueous methanol solution to the reaction chamber in a preheated state to the boiling point, a superheated liquid film state is easily formed, which is advantageous in enhancing the generation efficiency of hydrogen.
Although the application of heat necessary for preheating may be performed using an electric heater as described later, for example, using the heat of combustion obtained by combustion equipment such as a burner or a boiler for the heat necessary for preheating You can also. Among the heat of combustion, it is preferable to use, for example, heat of a medium temperature range (about 250 ° C. to 350 ° C.) other than the heat of the target temperature range.

  The base 13 has a cylindrical tubular structure 16 whose one end is open and the other end is closed, and the other open end of the cylinder structure is closed, and the case 13 is housed in the case 11 And 11 has a lid member 17 for closing the other end, and a catalyst (not shown) is disposed on the outer peripheral surface of the cylindrical structure 16 so as to cover the periphery of the cylindrical structure 16 It has become.

Here, FIG. 4 shows a cross-sectional structure of the hydrogen generator 10 in a state in which the base 13 is accommodated in the exterior material 11. FIG. 4 is a cross-sectional view of the hydrogen generator of FIG. 2 taken along line A-A.
In a state in which the base 13 is inserted into and housed in the outer package 11, a reaction chamber 18 in which a reforming reaction by a catalyst is performed is provided between the inner wall surface of the outer package 11 and the surface of the cylindrical structure of the base 13. It is formed. In the reaction chamber 18, a catalyst 15 provided so as to cover the outer peripheral surface of the cylindrical structure along the circumferential direction of the cylindrical structure 16 of the base 13 is disposed.

As shown in FIG. 5, in the cylindrical structure 16 of the substrate 13, a sheet-like catalyst 15 is wound around the entire surface of the cylindrical shape to form a triple-layered laminated structure. That is, the sheet-like catalyst 15 is wound on the curved surface of the cylindrical structure 16 on the base 13, and a catalyst layer composed of three layers is disposed by being wound three times.
In the present embodiment, the case is described where the catalyst layer is formed by three layers of three layers of catalyst layers, but the laminated structure of the catalyst is not particularly limited, and the scale of the hydrogen generator is supplied. It can be appropriately selected according to various requirements such as the amount or flow rate or temperature of the methanol aqueous solution, the amount of hydrogen gas to be reformed, the supported amount of the catalyst, the type of the catalyst metal and the like.
Therefore, the number of turns of the catalyst to be wound is preferably 3 or more, and may be 5 or more, or 10 or more, as necessary. The upper limit of the number of turns is not limited, but may be, for example, 20 or less.

  The catalyst 15 has carbon cloth, which is a carbon sheet, and platinum particles, which are catalyst metals supported on the carbon cloth.

Preferred examples of the catalyst metal include platinum (Pt), palladium (Pd), ruthenium (Ru), nickel (Ni), and copper (Cu), and the catalyst metal may be a composite containing these metals. . The composite includes, for example, a composite composed of at least one metal selected from the group consisting of platinum, palladium, ruthenium, nickel and copper, and another metal different from the metal of the metal group. Other metals include zinc (Zn), manganese (Mn) and the like, preferably zinc or manganese, or zinc and manganese.
Examples of the catalyst metal which is a complex include Ni--Ru (1: 1), Ni--Cu (1: 1), Cu--Ru (2: 1), Cu--Mn (12: 1), etc. Can. The numerical values in parentheses indicate the molar ratio of the elements.
The composite is preferably a solid solution in that the aqueous methanol solution can be reformed more efficiently by the superheated liquid film system, and is preferably a solid solution containing at least one of platinum, ruthenium and nickel.

The carbon sheet is used as a carrier for supporting the catalyst metal. By using the sheet-like carrier, as in the present embodiment, it is possible to cover the outer peripheral surface of the cylindrical structure and to wind it in an overlapping manner. When carbon sheets on which a catalyst metal is supported are stacked and wound, the superheated liquid film state is generated in the aqueous methanol solution and the gas phase in the gas-liquid mixed phase existing in the vicinity of the catalyst particles while increasing the supported amount of the catalyst metal. It is suitable for efficiently releasing the ingredients. Therefore, solid-liquid contact can be secured and the heat transfer coefficient can be increased, thereby enabling efficient hydrogen generation, and further increasing the supply flow rate of the methanol aqueous solution to further increase the reaction opportunity due to solid-liquid contact, Hydrogen can be generated more efficiently than a carbon-supported catalyst that does not have a wound structure.
However, if the supply flow rate of the methanol aqueous solution becomes too large, liquid phase components that do not contribute to the reaction are likely to be generated through the gaps between the wound catalyst without contact with the catalyst (channeling), resulting in conversion Will reduce the rate of hydrogen production. By raising the temperature, the heat flux can be increased to improve the hydrogen generation rate. When the temperature is raised, it is desirable to keep the temperature in a range that does not lead to film boiling so that nucleate boiling that favors heat transfer does not convert to film boiling that is detrimental to heat transfer. By suppressing the temperature to a level not reaching film boiling, it is possible to efficiently generate hydrogen gas.
That is, it is important that the relationship between the amount of catalyst and the amount of aqueous methanol solution (raw material for reforming) capable of maintaining the superheated liquid film state is in the range where the solid-liquid contact state is secured. As a result, the reforming reaction of the reforming material can be efficiently advanced while flowing the reforming material supplied from one end side to the other end side.

It is important to consider the following points in order to maintain the catalyst in a state of being moderately wetted by the aqueous methanol solution (superheated liquid film state).
(1) Since the methanol aqueous solution reforming reaction is a reaction in which the liquid phase changes to a gas phase product in parallel with evaporation, the supplied amount of the methanol aqueous solution is such that the methanol aqueous solution does not evaporate completely and the superheated liquid is present It is preferable to adjust to a range that is not too small compared to the amount of catalyst, that is, a range in which solid-liquid contact does not become solid-gas contact.
(2) Also, since the reaction speed is increased by the catalyst active site becoming a foaming point and growing and desorbing air bubbles, the supply amount of the aqueous methanol solution supplied is adjusted to a range that is not too large compared with the catalyst amount. Preferably. Thereby, when the support is a carbon sheet, it is possible to maintain an appropriate wet state, and when the support is granular carbon, it is suspended and loss of the temperature difference at the solid-liquid interface is suppressed.
(3) Therefore, the heat transferred from the external heat source to the superheated liquid film from the external heat source causes the growth and detachment of the bubble by being placed under nucleate boiling conditions while maintaining the catalyst in a state of being properly wetted with the aqueous methanol solution. It can be strongly urged.
From the above, the relationship between the amount of catalytic metal [V ¹ ; g] and the amount of aqueous methanol solution capable of maintaining the superheated liquid film state [V ² ; L (liter)] The range shown is preferable, and the range shown by the following formula 2 is more preferable.
V ² / V ¹ = 10 g / L to 50 g / L ··· Formula 1
V ² / V ¹ = 15 g / L to 20 g / L ··· Formula 2

As the carbon sheet, carbon cloth or carbon felt can be used.
The carbon cloth refers to a cloth obtained by, for example, carbonizing fibers obtained by firing and carbonizing carbon fibers such as acrylic fibers, and using commercially available commercial products (for example, carbon cloth manufactured by Kuraray Chemical Co., Ltd.) Can.
Carbon felt refers to a sheet-like non-woven fabric in which short fibers of carbon fibers are intertwined without weaving carbon fibers, and commercially available products (for example, carbon cloth manufactured by Kuraray Chemical Co., Ltd.) can be used. .

As the catalyst, metal particles containing a catalyst metal are preferably supported, and the average primary particle diameter of the supported metal particles is preferably 10 nm or less. That is, by being supported in the form of metal particles, the surface area is increased, and when the average primary particle diameter of the supported metal particles is 10 nm or less, the foaming point in the liquid phase catalytic reaction is increased. The heat flux is increased to further improve the reforming reactivity.
The average primary particle size is preferably as small as possible from the viewpoint of reforming reaction activity, and is more preferably 5 nm or less. The lower limit value of the average primary particle diameter may be, for example, 2 nm.
The average primary particle size is a value obtained as an average value of primary particle sizes obtained by observing 20 arbitrary metal particles arbitrarily by observation with a transmission electron microscope.

The loading amount of the catalytic metal in the catalyst depends on the type of metal, temperature or the like, but in the catalyst of the present disclosure, the loading amount of the catalytic metal supported on the carbon sheet is 15 g / L to 150 g / L preferable.
When the supported amount of the catalyst metal supported on the carbon sheet is 15 g / L or more, the bubbling point in liquid phase catalytic reaction is increased, the state of nuclear boiling with a large heat transfer coefficient is easily maintained, and the hydrogen gas generation efficiency is excellent. . In addition, when the amount of the catalyst metal supported on the carbon sheet is 150 g / L or less, the particle diameter of the metal particles of the catalyst is adjusted to an appropriate range, and it is advantageous in that long-term stability can be easily obtained. .
The supported amount of the catalyst metal supported on the carbon sheet may be selected according to the type of the catalyst, and for example, in the case of a Pt-based catalyst, 15 g / m ^{3 to} 100 g from the viewpoint of securing a necessary amount because of high activity. / may be used as the ^{m 3,} if for example, the Cu-Mn-based catalysts, for ^inexpensive, may be ^{100g / m 3 ~150g / m 3} .

There is no restriction | limiting in particular in the preparation method of the catalyst by which the catalyst metal was carry | supported by the carbon sheet, You may produce by any method. The catalyst may be made, for example, by an impregnation method in which the support is impregnated in the metal-containing liquid.
In the case of the impregnation method, for example, it can be produced by the following method. That is,
First, a carbon material (for example, a carbon sheet with high surface area having pores) which has been pretreated with a base or the like is prepared. The carbon sheet is immersed in a stirring aqueous solution of potassium chloride potassium (K ₂ PtCl ₄ ) for 24 hours and then heat reduced using a 90 ° C. aqueous solution of sodium borohydride (NaBH ₄ ) to form platinum metal. , Wash with 1000 ml of distilled water. By vacuum-drying the washed platinum metal at 70 ° C. for 10 hours, a platinum-supported catalyst in which platinum particles are supported on a carbon sheet can be produced.

The catalyst in the present disclosure reforms the aqueous methanol solution in the form of a superheated liquid film. Aqueous solution reforming is a reforming reaction in which a catalytic reaction is performed in a liquid phase to generate hydrogen, and is distinguished from a steam reforming reaction in which hydrogen is generated using steam.
When aqueous solution reforming is performed, the quantitative relationship between the amount of catalyst and the aqueous methanol solution is important in the liquid phase catalytic reaction that generates a gas.
In a reaction system in which the amount of aqueous methanol solution is too large relative to the amount of catalyst, as shown in FIG. 8C, catalyst particles supported on granular carbon will be present in a suspended state. Since the temperature of the suspension is equal to the boiling point of the liquid phase, the dehydrogenation activity of this reaction system is small. On the other hand, in a reaction system in which the amount of catalyst is increased to form a state (wet state) in which the catalyst is appropriately moistened with the aqueous methanol solution as shown in FIG. 8 (b), the catalyst temperature is higher than the boiling point of the aqueous methanol solution It becomes high state (overheated state). And, the dehydrogenation activity is maximized when the catalyst is in a wet state with a methanol aqueous solution. Such a state is called "superheated liquid film state".
On the other hand, as shown in FIG. 8A, in a reaction system in which the amount of aqueous methanol solution is too small relative to the amount of catalyst, when the aqueous methanol solution gradually loses weight and becomes depleted, solid-gas contact occurs. It becomes smaller. On the other hand, generally, when the temperature of the heat transfer surface is increased too much, generated bubbles coalesce to form a vapor film to cover the heat transfer surface, so film boiling occurs, but in film boiling, solid-gas contact is made. Therefore, good heat transfer from the heat transfer surface can not be expected.
In liquid phase catalytic reactions that produce a gas, it is preferable to use nucleate boiling which has a large heat transfer coefficient. In the region of nucleate boiling, a superheated liquid is generated in the heat transfer film at the solid-liquid interface, and the substance and heat are supplied from the liquid phase to the bubbles through gas phase formation and evaporation. At this time, if catalyst particles are present, the catalyst particles serve as a foam point. In order to increase the surface area of the catalyst particles to be the foaming point, the catalyst particles are preferably small particles, and particles of nano order size are preferable. Thereby, the foaming point can be increased and generation of isolated cells can be promoted.
In addition, since the endothermic reaction is added to the phase change, the heat transfer coefficient is improved, and the growth and detachment of the bubble become advantageous. Methanol molecules in the superheated liquid immediately adsorb and react on the catalytically active sites opened by the release of bubbles.
High bubble withdrawal frequency can result in high heat flux and empty site surface density to improve reaction rates.

Here, a catalyst layer having a three-layer structure in which the sheet-like catalyst 15 is wound three times will be described.
In the liquid phase (methanol aqueous solution), catalyst metal particles of nanoscale are supported on the surface of the carbon sheet in the sheet-like catalyst 15, and the micropores of the carbon sheet are methanol aqueous solution (methanol: water = 1: 1 [ The molar ratio] is stored and made wet.
Methanol aqueous solution, which has been preheated to near the boiling point, is capillary-condensed in the pores of the carbon sheet and repeats pore condensation and surface movement from one end of the sheet to the other end, resulting in endothermic reforming reaction and evaporation. proceed. At that time, the reaction chamber 18 is heated from the both sides of the substrate 13 side and the exterior material 11 side at a temperature exceeding the boiling point of the aqueous methanol solution.
The aqueous methanol solution, which was only the liquid phase at one end of the sheet, changes to a gas-liquid mixed phase while moving in the reaction chamber, and thus the catalyst and solid aqueous solution are in solid-gas contact. And the reaction rate specific to the superheated liquid film state can not be maintained.
Based on such a situation, in one embodiment of the present disclosure, the gas phase component of the gas-liquid mixed phase is formed between the sheets by arranging the catalyst as a laminated structure in which a carbon sheet supporting a catalyst metal is wound multiple times. Of the reaction system through the gap between This facilitates stable nucleation boiling in the liquid phase, which is advantageous for promoting the reforming reaction on the catalyst well.

Further, in the case where a plurality of sheet-like catalysts 15 are stacked, the generation rate of hydrogen is approximately proportional to the number of laminated sheet-like catalysts when the feed rate of the substrate such as methanol aqueous solution is changed. That is, by superposing the sheet-like catalyst, the volumetric density of the metal particles of the catalyst in the reactor can be increased while maintaining the superheated liquid film state. In this respect, it is significant to use sheet-like catalysts in piles.
For example, as shown in FIG. 6, a catalyst in which 12 mg of platinum particles are supported on a carbon cloth of φ4 cm is used as it is or a plurality of sheets are stacked to prepare a circular catalyst of single layer structure, two layer structure or three layer structure, Each was placed in contact with the heating surface. Then, 2-propanol (boiling point: 82.4 ° C.) heated to 150 ° C. was dropped to the center of the circular catalyst from the side farthest from the heating surface. As a result, as shown in FIG. 7, it was found that the hydrogen generation rate was approximately proportional to the number of layers.
The dripped 2-propanol moves by surface diffusion in the surface of the multilayer circular catalyst, while heat is transferred from the outside in the direction orthogonal to the surface of the circular catalyst, and the superheated liquid film state It is effective to maintain the reforming reaction in

Further, as shown in FIG. 4, a heating chamber 19 for heating a catalyst disposed on the surface of the cylindrical structure 16 is provided inside the cylindrical structure 16. By controlling the heating temperature in the heating chamber 19, the catalyst can be heated and controlled to a desired temperature range through the wall material forming the curved surface of the cylindrical structure.
The heating chamber 19 may be configured as a combustion chamber that heats the cylindrical structure with the heat of combustion when the fuel is burned. In this case, a fuel supply system for supplying the fuel to the heating chamber and an exhaust system for discharging the combustion exhaust gas may be attached. The heating chamber 19 may be a heating chamber in which an electric heater is disposed. As the electric heater, any of a heating heater, a radiation heater and the like may be used.

Furthermore, a tape heater, which is a heater for heating the catalyst via the sheathing material, is disposed outside the sheathing material 11 that accommodates the cylindrical structure 16. Thereby, as shown in FIG. 4, the catalyst 15 in the reaction chamber 18 is heated from both sides of the base 13 side and the exterior material 11 side.
As the heater, in addition to the tape heater, a combustion exhaust heat transfer device that heats using combustion exhaust heat may be used.

  For the application of heat necessary for heating the catalyst, it is preferable to use a part of the heat of combustion obtained by the combustion device 70 such as a burner, for example. In the present disclosure, among the combustion heat obtained by the combustion device, the heat of the originally intended temperature range is used for the intended purpose, and for example, the middle temperature range (about 250 ° C. to 350 ° C.) other than the heat of the intended temperature range. The heat of the above can be used to heat the hydrogen generator. Specifically, using a so-called combustion exhaust heat transfer device that heats with combustion exhaust heat, the amount of heat required by the hydrogen generator at system startup is covered by the combustion exhaust heat obtained by the combustion equipment 70 such as a burner. preferable. In this case, the heat of combustion may be used to heat the reaction chamber, or may be used to preheat the aqueous methanol solution supplied to the reaction chamber.

  It is preferable that the base 13 and the package 11 be formed of a heat transfer material so that heating for raising the temperature of the catalyst can be performed. As a heat transfer material, metal is preferable. The metal is not particularly limited, and in view of heat resistance or corrosion, for example, a stainless alloy (so-called SUS material) is preferable.

  As a heating temperature of a catalyst, 150 ° C-350 ° C is preferred, and 250 ° C-350 ° C is more preferred.

A condensation separator 20, which is a condensation separation device, is connected to the hydrogen generator 10 by a gas discharge pipe 12.
When hydrogen is generated in the hydrogen generator 10, the hydrogen is discharged to the gas discharge pipe 12 as a mixed gas mixed with other gas components, and the mixed gas pump P1 attached to the gas discharge pipe 12 is operated, The mixed gas is sent to the condenser separator 20 via the gas discharge pipe 12. The mixed gas includes hydrogen gas, carbon dioxide, carbon monoxide, water vapor, and unreacted methanol.

The condensation separation device condenses a mixed gas containing hydrogen gas generated by a hydrogen generator, and utilizes a difference in boiling point to generate a gas component (hydrogen-containing gas) such as hydrogen gas and a condensable component (condensate). Separate and purify.
At this time, gas components include hydrogen, carbon dioxide and carbon monoxide. Thus, condensation can separate hydrogen, carbon dioxide and carbon monoxide gas components from the mixed gas.
As a condensation separation device, an apparatus capable of separating a mixed gas of hydrogen and carbon dioxide or a mixed gas of hydrogen, carbon dioxide and carbon monoxide from unreacted methanol and water by condensation is arbitrarily selected and used can do. As a condensation separation device, for example, a distillation device may be used.

  Connected to the condensation separator 20 is one end of a return pipe 24 which is a resupply means for subjecting the aggregate to an aqueous solution reforming reaction in the hydrogen generator 10. The aggregates separated from gas components such as hydrogen gas in the condensing separator 20 are discharged from the condensing separator 20 through the return pipe 24.

The return pipe 24 is connected to the upstream side of the flow direction of the aqueous methanol solution of the raw material supply pipe 14 whose other end is connected to the hydrogen generator. Thus, the hydrogen generator 10 and the condenser separator 20 are in communication with each other by the return pipe. The condensate flowing through the return pipe 24 is returned to the raw material supply pipe 14 and supplied to the reaction chamber of the hydrogen generator by operating the raw material supply pump P2. The condensate supplied to the reaction chamber is recycled to the aqueous solution reforming reaction. Then, the same amount of methanol and water as the aqueous methanol solution subjected to the aqueous solution reforming reaction is newly supplied from the raw material supply device 50 to the hydrogen generator as an aqueous methanol solution.
In this way, the unreacted methanol and water remaining in the condensate after hydrogen gas separation is recycled to the aqueous solution reforming reaction through the circulation path, allowing complete conversion of the supplied methanol Become.

  Although not shown, a drive pump may be installed in the return pipe 24 for allowing the liquid phase condensate to flow well through the pipe as necessary.

A hydrogen storage tank 30 is connected to the condensation separator 20 by a hydrogen flow pipe 22.
After the gas component (hydrogen-containing gas) is separated from the mixed gas generated by the hydrogen generator 10 in the condensation separator 20, the separated hydrogen-containing gas is temporarily stored in the hydrogen storage tank 30. The hydrogen-containing gas may contain carbon dioxide and the like in addition to hydrogen.
The hydrogen-containing gas generated by the hydrogen generator can be directly supplied to the fuel cell, but it is temporarily stored in the hydrogen storage tank 30, and the necessary amount is supplied to the fuel cell according to the operating condition of the fuel cell system. Is preferred.

  A polymer electrolyte fuel cell (PEFC) 60 is connected to a hydrogen storage tank 30 by a hydrogen supply pipe 26. The PEFC 60 is a fuel cell using a polymer membrane (ion exchange membrane) having ion conductivity as an electrolyte between the electrodes, and a general PEFC that has been conventionally known can be used. In addition, fuel cells other than the polymer electrolyte fuel cell (PEFC) may be used.

  The hydrogen supply pipe 26 is provided with a valve V1, and the degree of opening of the valve V1 is controlled in response to a signal from the control device 40 to control hydrogen from the hydrogen storage tank 30 according to the required amount of PEFC 60 (hydrogen containing Gas) is supplied.

  Further, a hydrogen permeable membrane 28 is attached to the hydrogen supply pipe 26. The hydrogen permeable film 28 is a film capable of selectively passing hydrogen in the hydrogen-containing gas, and for example, an alloy thin film containing palladium (Pd) or the like can be used. Thus, the hydrogen concentration in the gas flowing through the hydrogen supply pipe 26 can be increased, and hydrogen gas (preferably pure hydrogen gas) having a high hydrogen concentration can be supplied to the PEFC 60.

A combustible gas pipe 32 provided with a valve V2 is connected to the hydrogen storage tank 30.
As described above, when hydrogen is selectively separated from the hydrogen-containing gas by the hydrogen permeable membrane 28, the concentration of gas components other than hydrogen (in particular, combustible gases such as carbon monoxide and hydrogen) in the hydrogen storage tank 30. Will be higher. Therefore, by operating the valve V2, gas components (flammable gas) other than hydrogen can be discharged to the outside through the combustible gas piping 32. The opening degree of the valve V2 is controlled, for example, by providing a hydrogen detection sensor for detecting, for example, hydrogen concentration in the hydrogen storage tank 30 and receiving a signal from the control device 40 based on the detection value of the hydrogen detection sensor It is also good.
A burner 70, which is an example of a combustion device, is connected to the combustible gas pipe 32, and the combustible gas is supplied to the burner through the combustible gas pipe 32 and is provided for combustion. The heat of combustion obtained by the burner can be used to heat the catalyst in the hydrogen generator and to preheat the aqueous methanol solution supplied to the hydrogen generator. This also enables effective use of energy.
As described above, by controlling the opening degree of the valve V2 in response to the signal from the control device 40, the concentration of the gas component other than hydrogen in the hydrogen storage tank 30 is maintained within the expected range, and hydrogen Other gas components can also be used effectively.
In addition, although the example which used the burner as a combustion apparatus was demonstrated here, even if combustion apparatuses other than a burner are connected, the same effect can be anticipated.

  As described above, the hydrogen-containing gas separated by the condensation separator 20 is temporarily stored in the hydrogen storage tank 30, and then purified through the hydrogen permeable membrane 28. Hydrogen gas according to the required amount of PEFC is supplied to the PEFC 60 Be done.

The controller 40 controls the operation of a fuel cell system provided with a hydrogen generation system.
As shown in FIG. 1, the control device 40 is electrically connected to the mixed gas pump P1, the raw material supply pump P2, the condensation separation device, etc., and operates the hydrogen generation system and the fuel cell system including the same. I have control.

Next, hydrogen generation and external supply of power in the fuel cell system according to an embodiment of the present disclosure will be outlined.
First, when the raw material supply pump P2 is operated, a liquid reforming raw material (methanol aqueous solution) is supplied to the hydrogen generator 10 from the supply port of the raw material supply device 50 through the raw material supply pipe 14. Specifically, as shown in FIG. 4, the reforming raw material supplied from the supply port 14 a to the hydrogen generator 10 has an inner wall of the outer package 11 and a cylindrical structure of the base 13 housed in the outer package. It is introduced into a reaction chamber 18 formed between the outer peripheral surface and the outer peripheral surface. A catalyst 15 is disposed in the reaction chamber 18 so as to cover the entire periphery of the cylindrical structure of the base 13.

The aqueous methanol solution of liquid supplied from the supply port 14a to the reaction chamber 18 flows along the surface of the cylindrical structure in the longitudinal direction of the cylindrical structure of the base 13 and moves to the side where the discharge port 12a is provided. Do. The aqueous methanol solution is preheated while moving in the reaction chamber, and is reformed in an aqueous solution by contacting with the metal particles of the catalyst in a state of being heated to a temperature above the boiling point.
At this time, the catalyst metal of the catalyst 15 is supported on a carbon sheet, and there is formed a state (wet state) appropriately wetted by an aqueous methanol solution. At this time, the catalytic metal is in the heat transfer film, the temperature is higher than the boiling point of the aqueous methanol solution (superheated state), and the dehydrogenation activity is maximized. That is, at this time, it is in the "superheated liquid film state".

  In addition, as described above, the nanoscale catalyst metal particles are supported on the high surface area activated carbon having excellent heat transferability, and the catalyst metal particles become the foaming point in the liquid phase, so that the nuclear boiling progresses. In the region of nuclear boiling, a superheated liquid is generated in the heat transfer film at the solid-liquid interface, and if the temperature difference between the heating temperature and the boiling point is appropriate, the substance and heat are supplied from the liquid phase to the bubbles. Since the endothermic reaction is added to the phase change, the heat transfer coefficient is improved, and the growth and detachment of the bubbles become advantageous. The reaction speed is improved because the methanol molecules of the superheated liquid immediately adsorb and react to the catalytically active sites which are freed by the desorption of the bubbles.

In the catalyst 15, as shown in the following reaction formula, an aqueous solution reforming reaction of methanol (Formula 3) proceeds to generate hydrogen. Further, depending on the catalyst, the aqueous solution reforming reaction of Formula 3 and the methanolysis reaction (Formula 4) proceed to generate hydrogen.
CH ₃ OH + H ₂ O → 3H ₂ + CO ₂ ··· Formula 3
CH ₃ OH → 2H ₂ + CO formula 4

The generated gaseous hydrogen moves in the reaction chamber together with by-produced carbon dioxide or carbon dioxide and carbon monoxide and unreacted methanol, etc., is discharged as a mixed gas from the exhaust port 12a, and is attached to the gas exhaust pipe 12 The mixed gas is sent to the condensing separator 20 by operating the mixed gas pump P1.
In the condensation separator 20, a hydrogen-containing gas including the condensable components methanol and water, the non-condensable components hydrogen, carbon dioxide, and optionally by-product carbon monoxide contained in the supplied mixed gas And the separated hydrogen-containing gas is stored in the hydrogen storage tank 30. Thereafter, purified hydrogen is produced by passing the hydrogen-containing gas through the hydrogen permeable membrane. If the purpose of using purified hydrogen is to fuel PEFC power generation, carbon monoxide can not be used as fuel for PEFC, for example, combustion to obtain the heat needed for reforming in a hydrogen generation system It is temporarily stored in the hydrogen storage tank 30 so as to be used as fuel for the device.
The hydrogen-containing gas separated by the condensation separator 20 is once sent to the hydrogen storage tank 30 through the hydrogen flow pipe 22 connected to one end of the condensation separator 20. Thereafter, the hydrogen-permeable membrane 28 attached to the hydrogen supply pipe 26 makes it into purified hydrogen containing no carbon monoxide and the like, and is sent to the PEFC 60. By supplying the purified hydrogen gas, the PEFC 60 can generate power.
On the other hand, the condensable component (condensate) after the hydrogen gas is separated in the condensation separator 20 can be discharged and removed through the discharge pipe connected to the other end of the condensation separator 20 and reused as a methanol aqueous solution it can.

Next, a modification of the fuel cell system of the present disclosure will be described with reference to FIG.
In FIG. 9, the same components as those of the above-described hydrogen generation system shown in FIGS. 1 to 8 are designated by the same reference numerals, and the description thereof will be omitted.

  The fuel cell system 200 shown in FIG. 9 includes two hydrogen generation systems by including two hydrogen generation systems. The fuel cell system 200 has two hydrogen generators connected in series, so that the unreacted hydrogen remaining on the upstream hydrogen generator without being used for aqueous solution reforming can be reduced. It is an aspect of improving the conversion efficiency of methanol aqueous solution by this to the hydrogen generator of the above, and improving the amount of hydrogen generation. In this embodiment, the unreacted methanol is returned to the same hydrogen generator and the aqueous solution is reformed in that the unreacted methanol is supplied to another hydrogen generator among the methanol aqueous solution supplied to the hydrogen generator. This is different from the previously described hydrogen generation system shown in FIG.

  As shown in FIG. 9, the hydrogen generation system of the present embodiment includes two hydrogen generators 10 and 10A, and a hydrogen-containing gas containing a hydrogen gas generated by the hydrogen generator 10 on the upstream side and a condensate. Is separated by the condensation separator 20, and the unreacted methanol aqueous solution in the separated condensate is supplied to the hydrogen generator 10A on the downstream side through the resupply pipe 34 which is a resupply means.

The resupply pipe 34 connects the condensation separator 20 and the hydrogen generator 10A. A raw material supply pump P2A is attached to the resupply pipe 34, and by operating the raw material supply pump P2A, the condensate discharged from the condensation separator 20 is supplied to a hydrogen generator and subjected to an aqueous solution reforming reaction. . In this case, methanol and water may be separated from the condensate discharged from the condensation separator 20, and methanol and water may be selectively circulated to the re-supplying pipe. In this case, methanol and water have a composition suitable for the reforming reaction (for example, methanol: water = 1: 1 (molar ratio)), for example, by analyzing the composition of the condensate discharged from the condensation separator 20. Methanol and water may be passed through the resupply pipe 34 after adjusting the mixing ratio as described above. The adjustment of the mixing ratio may be performed, for example, by compensating for the deficient component such as methanol from the outside.
The methanol re-supplied through the re-supply pipe 34 is reformed in an aqueous solution by the hydrogen generator 10A to generate hydrogen, and the hydrogen is sent to the condensation separator 20A as a hydrogen-containing gas. In the condensation separator 20A, the hydrogen-containing gas and the condensate are separated in the same manner as the condensation separator 20. The hydrogen-containing gas is temporarily stored in the hydrogen storage tank 30 through the hydrogen flow pipe 22A. The hydrogen-containing gas may contain carbon dioxide and the like in addition to hydrogen.
The hydrogen-containing gas generated by the hydrogen generator can be directly supplied to the fuel cell, but it is temporarily stored in the hydrogen storage tank 30, and the necessary amount is supplied to the fuel cell according to the operating condition of the fuel cell system. Is preferred.
A hydrogen supply pipe 26 having a valve V1 is connected to the hydrogen storage tank 30, and is communicated with the PEFC 60 through the hydrogen supply pipe 26, and hydrogen from the hydrogen storage tank 30 according to the required amount of PEFC 60 (hydrogen-containing Gas) is supplied. The PEFC 60 supplied with hydrogen can generate electricity. The condensate separated by the condensation separator 20A is discharged from the condensation separator 20A to the outside because the residual amount of methanol is small.

  In the hydrogen generation system of this embodiment, since the unreacted hydrogen remaining in the condensate is reformed in an aqueous solution (preferably after adjusting the composition of the unreacted methanol and water) in the hydrogen generator 10A on the downstream side. And the conversion efficiency of the aqueous methanol solution in the whole system can be enhanced. Thereby, it is possible to further improve the hydrogen production amount.

In the hydrogen generation system of the present embodiment, the configuration in which two hydrogen generators and two condensing separators are disposed is mainly described, but the number of hydrogen generators is not limited to two, and it is determined according to the remaining ratio of unreacted methanol. Three or more units may be disposed in series and / or in parallel.
As another modification, two hydrogen generators are disposed in parallel, and the condensate discharged from the two hydrogen generators and condensed and separated by the condensing separator is used as both of the two hydrogen generators. Alternatively, the unreacted methanol may be reformed in an aqueous solution by supplying it to a downstream hydrogen generator disposed in series with the above. Also by this, it is possible to enhance the conversion efficiency of the methanol aqueous solution and to improve the hydrogen production amount.
Moreover, although not shown in the figure, the condensing separation apparatus is not limited to two, but for example, one condensing separation apparatus is disposed for two hydrogen generation apparatuses, and hydrogen-containing gases are collectively collected at one place. It may be configured to perform condensation and separation, or three or more units may be disposed to correspond to the number of disposed hydrogen generators.

In the above embodiment, the hydrogen generator in which the base whose one end is closed is accommodated in the outer covering material is described as an example, but the base is open at both ends in the longitudinal direction of the base and has, for example, a cylindrical shape through which hot air flows. It may be configured.
Further, although the case where platinum is used as the catalyst metal has been described above, the same or more effect can be obtained also when using a catalyst metal other than platinum.
Furthermore, in the above embodiment, the structure in which the catalyst layer composed of three layers is disposed by winding the carbon sheet supporting the catalyst metal three times has been described as an example, but the scale of the reaction chamber of the hydrogen generator That is, the same effect can be obtained even when the multilayer catalyst layer is disposed by winding four or more times depending on the amount of generated hydrogen gas and the like.

DESCRIPTION OF SYMBOLS 10, 10A ... Hydrogen production apparatus 11 ... Exterior material 12, 12A ... Gas discharge pipe 12a ... Discharge port 13 ... Base 14, 14A ... Raw material supply pipe 14a ... Supply port 15 ... catalyst 16 ... cylinder structure 17 ... lid 18 ... reaction chamber 19 ... heating chamber 20, 20A ... condensation separation device 22, 22A ... hydrogen circulation pipe 24 ... · Return piping (resupply means)
26 · · · Hydrogen supply pipe 28 · · · hydrogen permeable membrane 30 · · · hydrogen storage tank 32 · · · flammable gas piping 34 · · · re-supply piping (re-supply means)
40: Control device 50: Raw material supply device 60: Solid polymer fuel cell (PEFC)
70 ・ ・ ・ Burner (combustion equipment)
100, 200 ... fuel cell system P1, P1A ... mixed gas pump P2, P2A ... raw material supply pump V1, V2 ... valve

Claims (11)

A hydrogen generator for reforming the aqueous methanol solution to produce hydrogen gas;
A condensing separation device which is supplied with a mixed gas containing hydrogen discharged from the hydrogen generator and condenses the supplied mixed gas to separate at least hydrogen gas and a condensate;
Resupplying means for resupplying a hydrogen generator with at least unreacted methanol in the condensate separated by the condensing separator and supplying it to an aqueous solution reforming;
And the hydrogen generator comprises
A base having a cylindrical structure in which at least one end is open, and in which the heating chamber is disposed inside the cylindrical structure;
A catalyst which is disposed so as to cover at least a part of the outer peripheral surface of the cylindrical structure of the substrate, and in which a catalyst metal is supported on a carbon sheet;
An exterior material that accommodates the base on which the catalyst is disposed;
A discharge port disposed on the side of the one end in the longitudinal direction of the cylinder of the substrate and discharging hydrogen gas;
A supply port disposed on the side of the other end in the longitudinal direction of the cylinder of the substrate, for supplying a methanol aqueous solution between the substrate and the sheathing material;
A hydrogen generation system for reforming the supplied aqueous methanol solution with the catalyst to produce hydrogen gas.   The hydrogen generation system according to claim 1, wherein the catalyst is wound around the outer peripheral surface of the substrate to form a laminated structure.   3. The hydrogen generation system according to claim 1, wherein a loading amount of the catalyst metal supported on the carbon sheet is 15 g / L to 150 g / L for the catalyst.   The hydrogen generation system according to any one of claims 1 to 3, wherein the catalyst reforms the supplied aqueous methanol solution in a superheated liquid film state.   The aqueous methanol solution supplied from the supply port is preheated while being circulated in the length direction of the cylinder of the substrate, and the aqueous solution is reformed by the catalyst in a state of being heated to a temperature exceeding the boiling point. The hydrogen generation system according to any one of 4.   The hydrogen generation system according to any one of claims 1 to 5, wherein the carbon sheet is carbon cloth or carbon felt.   A complex of at least one selected from the group consisting of platinum, palladium, ruthenium, nickel or copper, or platinum, palladium, ruthenium, nickel and copper with other metals different from the metals of the above metal group. The hydrogen generation system according to any one of claims 1 to 6, which is   The hydrogen generation system according to claim 7, wherein the other metal contains at least one of manganese and zinc.   The hydrogen generation system according to any one of claims 1 to 8, wherein the catalyst metal is a solid solution containing at least one of platinum, ruthenium and nickel.   The hydrogen generation system according to any one of claims 1 to 9, wherein the catalyst supports metal particles containing the catalyst metal, and the average primary particle diameter of the metal particles is 10 nm or less. A hydrogen generation system according to any one of claims 1 to 10;
A fuel cell that generates electricity from hydrogen gas generated by the hydrogen generator;
Fuel cell system equipped with