JP2011195349A - Apparatus for producing hydrogen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an apparatus for producing hydrogen that uses a precise hollow support as a support for a reforming catalyst serving also as a support and uses the reforming catalyst serving also as a support as a support for a hydrogen separation membrane, wherein all gases of a feed gas, hydrogen and an offgas are made to flow through the reforming catalyst serving also as a support.SOLUTION: The apparatus for producing hydrogen is composed of the precise hollow support having a hollow part through which the feed gas flows, the porous reforming catalyst serving also as a support adhered to the outer peripheral surface of the precise hollow support, and the hydrogen separation membrane on the outer peripheral surface of the reforming catalyst serving also as a support. The feed gas flows through the hollow part inside the precise hollow support, turning at the end thereof in the direction of flow, and forms a reformed gas from the feed gas while flowing in the reforming catalyst serving also as a support. The formed reformed gas is purified through the hydrogen separation membrane to produce high-purity hydrogen.

Description

  The present invention relates to a hydrogen production apparatus for producing a reformed gas by steam reforming of a hydrocarbon gas and producing high-purity hydrogen by purifying the produced reformed gas with a hydrogen separation membrane.

One of the industrial methods for producing hydrogen is a hydrocarbon gas steam reforming method. In the steam reforming method, a reformer filled with a reforming catalyst such as a granule is usually used. The reformed gas obtained by the steam reformer contains by-products such as CO and CO ₂ and surplus H ₂ O in addition to hydrogen as a main component. For this reason, if the reformed gas is used as it is in, for example, a fuel cell, the cell performance is hindered.

  Among fuel cells, the CO in hydrogen gas used in phosphoric acid fuel cells (PAFC) is about 1% (vol%, the same applies hereinafter), and the polymer electrolyte fuel cell (PEFC) is about 100 ppm (volppm, the same applies hereinafter). If these are exceeded, battery performance will be significantly degraded. For this reason, these by-products must be removed before being introduced into the fuel cell. In addition, hydrogen used for hydrogen addition to an unsaturated bond or oxyhydrogen flame is usually packed in a cylinder, and its purity is required to be 5N (= 99.999%) or more.

  There is a membrane reactor as an apparatus integrated so that generation of the reformed gas by the steam reformer and purification of the generated reformed gas can be performed by one apparatus. In the membrane reactor, the hydrocarbon gas is reformed by the reforming catalyst layer by a reforming reaction with water vapor using the heat generated in the burner as a heating source, and becomes a reformed gas. Hydrogen in the reformed gas is selectively separated by a hydrogen separation membrane such as a Pd membrane and taken out as purified hydrogen.

  The raw material gas (hydrocarbon gas + water vapor) flows through the flow path parallel to the reforming catalyst layer and flows into the surface of the reforming catalyst layer and into the reforming catalyst layer to be reformed. Hydrogen in the reformed gas is selectively separated by a hydrogen separation membrane arranged after the reforming catalyst layer and taken out as purified hydrogen, and gases other than hydrogen (including unreacted source gas) are discharged as off-gas. .

  Various devices and improvements have been added to the reforming catalyst integrated module. FIGS. 1 to 3 are diagrams illustrating an example of a hydrogen production apparatus using an outer membrane type cylindrical reaction tube in which a hydrogen separation membrane is arranged on the surface of a porous reforming catalyst / support (Japanese Patent Laid-Open No. 2005-249867). 2004-149332). As shown in FIG. 1, an outer membrane type cylindrical reaction tube is used as the cylindrical reaction tube.

JP 2004-149332 A

  2 to 3 show the structure of the outer membrane type cylindrical reaction tube. This outer membrane type cylindrical reaction tube is set in the outer tube as shown in FIG. 1 to constitute a hydrogen production apparatus. This reaction tube is configured by forming a Pd film on the outer peripheral surface of a cylindrical reforming catalyst / support composed of, for example, Ni—YSZ cermet. The Pd film is formed by an electroless plating method or the like. As shown in FIG. 1, the upper part of the cylindrical reaction tube and the upper part of the outer tube are closed by a lid. An inner tube is arranged at intervals in the cylindrical reaction tube, and an outer tube is arranged around the cylindrical reaction tube.

  The porous reforming catalyst / support may be formed in a cylindrical shape or a flat plate shape. FIGS. 1 to 3 show an outer membrane type cylindrical reaction tube in a cylindrical configuration. As shown in FIGS. 1 to 3, the outer membrane type cylindrical reaction tube is configured by disposing a hydrogen separation membrane on the outer side of the cylindrical reforming catalyst / support, that is, the outer peripheral surface. For reforming the hydrocarbon gas, it is necessary to heat to about 450 to 680 ° C. For this heating, for example, an outer membrane type cylindrical reaction tube is surrounded and a combustion gas such as city gas is supplied into the space.

  In general, when the hydrogen production apparatus configured as described above is operated, city gas is burned with air by a burner, and the temperature of the cylindrical reaction tube is increased. Taking FIG. 1 as an example, after reaching a predetermined temperature, a raw material gas (hydrocarbon gas + water vapor) is supplied from the lower part to the inner pipe and folded at the upper part between the inner pipe and the cylindrical reforming catalyst / support. To introduce. The hydrocarbon gas is reformed by the catalytic action of the reforming catalyst of the cylindrical reforming catalyst / support.

Hydrogen in the generated reformed gas selectively permeates through the Pd membrane and is selectively separated, and is taken out as high-purity hydrogen through a gap between the cylindrical reforming catalyst / support and the outer tube. Components other than hydrogen in the reformate gas, i.e. CO, etc. (H ₂ retentate with Pd film) CO _2, H ₂ passes between the inner tube and a cylindrical reaction tube, and is discharged as off-gas.

  Thus, the membrane reactor is very useful in principle because the reformed gas can be generated and purified with a single device. However, there is a space through which gas can flow as shown by S in FIGS. 1 and 3 between the inner tube (inner tube) and the reforming catalyst / support. Since the reforming catalyst / support is porous, it has gas permeability but has a larger resistance (gas flow resistance) than the space between the intubation tube and the reforming catalyst / support, and some gases Is discharged outside the module without passing through the reforming catalyst / support.

  The present invention solves the above problems that occur in a hydrogen production apparatus including an outer membrane cylindrical reaction tube that generates reformed gas by steam reforming of hydrocarbon gas and purifies the generated reformed gas with high purity. A dense hollow support as a reforming catalyst / support or a reforming catalyst layer support, and a reforming catalyst / support as a support for a hydrogen separation membrane. An object of the present invention is to provide a hydrogen production apparatus in which all the off-gas passes through the reforming catalyst / support or the reforming catalyst layer.

  The present invention includes (1) a dense hollow support having a hollow portion which is a flow path for a source gas, and a porous reforming catalyst / support that is disposed in close contact with the outer peripheral surface of the dense hollow support. A hydrogen separation membrane is disposed on the outer peripheral surface of the reforming catalyst / support, the raw material gas is passed through the hollow portion inside the dense hollow support, and folded at the tip in the flow direction thereof to serve as the reforming catalyst / support. A hydrogen production apparatus characterized in that a reformed gas is produced from a raw material gas while flowing in a support, and the produced reformed gas is purified by a hydrogen separation membrane to produce high purity hydrogen.

  The present invention includes (2) a dense hollow support having a hollow portion which is a flow path for a source gas, a reforming catalyst layer disposed on the outer peripheral surface of the dense hollow support, and an outer periphery of the reforming catalyst layer. A hydrogen separation membrane is arranged, and the reformed gas is generated from the source gas while passing the source gas through the hollow portion inside the dense hollow support and turning back at the tip in the flow direction to flow through the reforming catalyst layer. Then, the produced reformed gas is purified by a hydrogen separation membrane to produce high-purity hydrogen.

  By substantially eliminating the space between the dense hollow support, that is, the intubation tube and the reforming catalyst layer or the reforming catalyst / support, the entire raw material gas, which is a mixed gas of hydrocarbon gas and steam, is reformed. Since it passes through the catalyst layer or the reforming catalyst / support, the raw material gas is allowed to react on the reforming catalyst, so that further increase in efficiency of the catalyst integrated module can be achieved. As a result, the raw material gas can be used effectively without being discharged to the outside of the module without being reacted. As a result, an increase in hydrogen production, that is, an increase in hydrogen production efficiency is achieved.

  In addition, when using the reforming catalyst / support, the entire module can be held by the intubation by integrating the intubation and the reforming catalyst / support. Is no longer necessary. As a result, the degree of freedom in designing the pore size and porosity of the porous reforming catalyst / support is increased. As a result, the gas pressure loss in the porous body can be reduced and the hydrogen production efficiency can be improved.

  Furthermore, according to the present invention, since all the raw material gas passes through the reforming catalyst layer or the reforming catalyst / support, the raw material gas, particularly hydrocarbon gas, is discharged outside the module without being reacted. Therefore, the source gas can be used effectively. As a result, an increase in hydrogen production, that is, an increase in hydrogen production efficiency is achieved.

FIG. 1 is a diagram illustrating a hydrogen production apparatus using an outer membrane type cylindrical reaction tube in which a hydrogen separation membrane is arranged on the surface of a reforming catalyst / support. FIG. 2 is a diagram for explaining a hydrogen production apparatus using an outer membrane type cylindrical reaction tube in which a hydrogen separation membrane is arranged on the surface of the reforming catalyst / support. FIG. 3 is a diagram for explaining a hydrogen production apparatus using an outer membrane type cylindrical reaction tube in which a hydrogen separation membrane is arranged on the surface of the reforming catalyst / support. FIG. 4 is a diagram for explaining the hydrogen production apparatus of the present invention. FIG. 5 is a diagram for explaining the hydrogen production apparatus of the present invention. FIG. 6 is a diagram for explaining the hydrogen production apparatus of the present invention. FIG. 7 is a diagram illustrating a hydrogen production apparatus according to the present invention. FIG. 8 is a diagram for explaining a barrier layer used in the hydrogen production apparatus of the present invention.

  The reforming catalyst integrated module is a membrane reactor for high-efficiency hydrogen production composed of a reforming catalyst layer and a hydrogen separation membrane. As one of means for producing hydrogen with higher efficiency, there is a method of improving the reaction rate by promoting contact between the raw material gas and the reforming catalyst.

  On the other hand, when the reforming catalyst integrated module is actually used, an intubation tube is disposed in the reforming catalyst layer or the reforming catalyst / support body. As described above, there is a space through which the source gas can flow between the intubation and the reforming catalyst layer or the reforming catalyst / support, and some of the source gases are supported by the reforming catalyst layer or the reforming catalyst / support. There was a possibility of being discharged outside the module without passing through the body. That is, a part of the raw material gas may not be in contact with the reforming catalyst layer or the reforming catalyst of the reforming catalyst / support, and may be discharged outside the module without being reacted.

  The present invention provides a dense hollow support having a hollow portion which is a flow path of a raw material gas, that is, an intubation tube, an intubation tube and a reforming catalyst layer or a reforming catalyst / support in close contact with each other. By substantially eliminating the space between the catalyst and the reforming catalyst layer or the reforming catalyst / support, more raw material gas, that is, hydrocarbon gas and steam react on the reforming catalyst, and the reforming catalyst is integrated. It is intended to achieve further improvement in efficiency of the hydrogen production apparatus that is a commutation module.

  The intubation is made of stainless steel or the like. 4-6 is a figure explaining the aspect of this invention. In the present invention, the reforming catalyst / support may be formed in a cylindrical shape or may be formed in a flat plate shape, but FIGS. FIG. 4 shows an outer membrane type cylindrical reaction tube, and FIGS.

  As shown in FIG. 4, in the outer membrane type cylindrical reaction tube, a dense hollow support body having a hollow portion at the center, that is, an intubation tube is arranged. Then, the reforming catalyst layer or the reforming catalyst / support is densely arranged on the outer peripheral surface. This substantially eliminates the space (gap) between the inner tube and the reforming catalyst layer or the reforming catalyst / support, so that all the raw material gases are supported by the reforming catalyst layer or the reforming catalyst / support. Since the raw material gas passes through the body, the raw material gas can be effectively used without being discharged to the outside of the module without being reacted. As a result, an increase in hydrogen production, that is, an increase in hydrogen production efficiency is achieved.

  In addition, by integrating the inner tube and the reforming catalyst layer or the reforming catalyst / support, the entire module can be held by the inner tube, so that the strength of the reforming catalyst layer or the reforming catalyst / support is high. Is no longer necessary. As a result, the degree of freedom in designing the pore diameter and porosity of the porous reforming catalyst layer or reforming catalyst / support is increased. As a result, the gas pressure loss in the porous can be reduced and the hydrogen production efficiency can be improved. In addition, since manufacturing restrictions are reduced, manufacturing costs can be reduced.

<About reforming catalyst and support>
The reforming catalyst / support is porous and plays the role of a reforming catalyst and a role of supporting the hydrogen separation membrane at the same time, and is an important configuration in the present invention. As a result, the hydrocarbon gas is steam reformed by the reforming catalyst / support to generate reformed gas, and the generated reformed gas is purified by the hydrogen separation membrane supported by the reforming catalyst / support, thereby achieving high purity. Produce hydrogen.

  As the reforming catalyst and support, a porous material having a function as a reforming catalyst and supporting a hydrogen separation membrane is used. For example, a mixture of nickel and yttria stabilized zirconia is used. Examples thereof include sintered bodies (= Ni—YSZ cermet), porous ceramics having such functions, and porous cermets.

  In the case of Ni-YSZ cermet, for example, Ni particles, NiO particles and YSZ (= yttria-stabilized zirconia) particles are mixed, the mixture is formed by extrusion molding, pressure molding or the like, and fired. The content of the Ni component in the sintered body is selected in the range of 10 to 70 wt%. This material exhibits a methane conversion rate of about 39% as a single catalyst when the reforming temperature = 600 ° C. and the S / C ratio = 3.0, and has almost the same reforming performance as a conventional granular reforming catalyst. is doing.

  As the hydrogen separation membrane, a metal membrane such as a Pd membrane or a Pd alloy membrane is used. In the Pd alloy, examples of the metal alloyed with Pd include Ag, Pt, Rh, Ru, Ir, Ce, Y, and Gd. The metal film is supported on the reforming catalyst / support by a plating method, a vapor deposition method or other appropriate methods. Here, the pore diameter of the porous ceramics is preferably 10 μm or less in relation to the thickness of the metal film. When the thickness of the metal film is 20 μm, the pore diameter of the porous ceramic is preferably about 10 μm. When the thickness of the metal film is 20 μm or less, the pore diameter of the porous ceramic is about 10 μm correspondingly. The following is preferable.

  Since the present reforming catalyst / support simultaneously functions as a reforming catalyst and supports the hydrogen separation membrane, a reforming catalyst layer that is essential in the conventional membrane reactor is not required. For this reason, the hydrogen production apparatus of the present invention can be remarkably reduced in size as compared with the conventional hydrogen production apparatus. In particular, the present reforming catalyst / support itself plays a role as a reforming catalyst and does not require a separate reforming catalyst layer. The problem of damage to the hydrogen separation membrane due to contact with the water does not occur.

  4-6 is a figure explaining the aspect of this invention. The reforming catalyst / support of the present invention is formed in a cylindrical shape. FIG. 4 shows an outer membrane type cylindrical reaction tube, and FIGS. As shown in FIG. 4, in the outer membrane cylindrical reaction tube, a dense hollow support body having a hollow portion at the center, that is, an intubation tube, is disposed, and the reforming catalyst / support body is disposed in close contact with the outer peripheral surface thereof. A hydrogen separation membrane is densely arranged on the outer peripheral surface.

  In this way, by placing the reforming catalyst / support closely in contact with the outer peripheral surface of the intubation tube, the space between the intubation tube and the reforming catalyst / support body is substantially eliminated, so that more The raw material gas is reacted on the reforming catalyst to achieve higher efficiency of the reforming catalyst integrated module. The same applies to the case where a reforming catalyst layer is disposed instead of the reforming catalyst / support.

  4 (b) to 4 (d) show aspects of the cross-sectional shape of the inner tube (the cross-sectional shape perpendicular to the longitudinal direction). The cross-sectional shape of the intubation tube may be a circular cross-section as shown in FIG. 4 (b), or may be a structure having an elliptical cross-section as shown in FIG. As shown in (d), a structure having a plurality of source gas flow paths with an elliptical outer peripheral cross section may be used.

  When using the outer membrane cylindrical reaction tube, the source gas is introduced from one end of the hollow portion of the inner tube and folded at the other end. The source gas flows into the reforming catalyst / support at the folded portion at the other end and is reformed by the reforming catalyst to become a hydrogen-rich reformed gas. The mixed gas of the reformed gas and the raw material gas flows through the reforming catalyst / support in the direction opposite to the raw material gas flow in the inner tube, and hydrogen in the mixed gas flow selectively flows through the hydrogen separation membrane. Extracted as high purity hydrogen.

  In the reforming catalyst / support, the raw material gas is sequentially reformed to become a hydrogen-rich reformed gas, and the generated reformed gas flows in the direction opposite to the raw material gas flow in the inner tube. The generated reformed gas flowing in the reforming catalyst / support is separated from the hydrogen by the hydrogen separation membrane, and the gas composed of carbon monoxide or the like that does not permeate the hydrogen separation membrane is turned off gas from the other end of the reforming catalyst / support. Discharged.

  FIG. 5 is a diagram for explaining a mode in which a plurality of outer membrane cylindrical reaction tubes shown in FIG. 4 are used in parallel. As shown in FIG. 5, the raw material gas is supplied through the raw material gas supply pipe 11 and is supplied into the inner tube of each outer membrane type cylindrical reaction tube via the header 12. The high-purity hydrogen produced and separated by each reforming catalyst / support and the hydrogen separation membrane is taken out via the lead-out pipe 13, and off-gas coming out of the reforming catalyst / support without passing through the hydrogen separation membrane is from the header 14. And is taken out through the discharge pipe 15.

  FIG. 6 is a diagram for explaining an embodiment in which a plurality of outer membrane cylindrical reaction tubes shown as FIGS. 4 (a) and 4 (d) are used in parallel. As shown in FIG. 6, the source gas is supplied through the source gas supply pipe 21 and is supplied into the inner tube of each outer membrane type cylindrical reaction tube via the header 22. The high-purity hydrogen produced and separated by each reforming catalyst / support and hydrogen separation membrane is taken out through the outlet pipe 23, and off-gas coming out of the reforming catalyst / support without passing through the hydrogen separation membrane is taken from the header 24. And is taken out through the discharge pipe 25.

  As described above, it is necessary to heat to about 450 to 680 ° C. for reforming the hydrocarbon gas that is the raw material gas. For the heating, for example, the outer membrane cylindrical reaction tube is surrounded by an outer tube having a hydrogen outlet tube (in the case of an outer membrane cylindrical reaction tube, the outermost layer is a hydrogen separation membrane, and hydrogen is hydrogen The gas is burned with air by a burner in the space surrounding the outer pipe, or the city gas is burned in the space surrounding the outer pipe. It is possible to heat by supplying. FIG. 7 shows an example of such a mode. It is heated by a burner that burns city gas etc. with air in a heating furnace. Reference numeral 16 denotes an exhaust pipe for exhaust gas from the heating furnace (exhaust gas derived from a burner flame, etc.).

<Regarding the barrier layer between the reforming catalyst / support and the hydrogen separation membrane>
In the hydrogen production apparatus of the present invention, a barrier layer can be provided between the reforming catalyst / support and the hydrogen separation membrane. The barrier layer is related to a previous application (Japanese Patent Laid-Open No. 2004-314163) by the present applicant (part), and the components between the reforming catalyst / support and the hydrogen permeable membrane as described below. Interdiffusion can be prevented.

JP 2004-314163 A

<Interdiffusion of components between reforming catalyst / support and hydrogen permeable membrane>
When the peripheral surface of the cylindrical reforming catalyst / support or one surface of the flat reforming catalyst / support and the hydrogen permeable membrane were integrated, it was observed that both components diffused. The metal (Ni) component of the reforming catalyst / support and the Pd of the hydrogen separation membrane are mixed, and the boundary portion between the reforming catalyst / support layer and the Pd membrane layer disappears. And it turned out that the complicatedness, ie, diffusion, is the cause of impairing the hydrogen permeation performance of the hydrogen permeable membrane.

  Therefore, in Patent Document 2, in order to prevent such diffusion, a barrier layer is provided between the reforming catalyst / support and the hydrogen permeable membrane. Thereby, it is possible to solve the problem of deterioration of the hydrogen separation performance of the hydrogen permeable membrane due to the mutual diffusion of components between the reforming catalyst / support and the hydrogen separation membrane. FIG. 8 is a diagram illustrating the barrier layer.

  As shown in FIG. 8, a barrier layer is provided on the surface of the substrate, that is, the reforming catalyst / support, and a hydrogen permeable membrane is disposed thereon. Thereby, mutual diffusion between the component of the reforming catalyst / support and the component of the hydrogen permeable membrane can be prevented. The barrier layer needs to be porous, but may be porous when formed, and may be porous when used as a reaction cylinder or reaction plate for a hydrogen production apparatus. In addition, when the barrier layer is provided in such a manner, the hydrogen permeable membrane can be more firmly held against the reforming catalyst / support by the so-called anchor effect by causing the components of the hydrogen permeable membrane to penetrate into the barrier layer. Can do.

  The thickness of the barrier layer can be appropriately selected within the range in which the purpose, that is, the prevention of mutual diffusion between the component of the catalyst / support and the hydrogen permeable membrane can be achieved. The range is preferably in the range of 5 to 100 μm. As the constituent material of the barrier layer, zirconia, stabilized zirconia, partially stabilized zirconia, alumina, magnesia, or a mixture or compound of these materials can be used.

  A barrier layer is provided between the reforming catalyst / support and the hydrogen permeable membrane. The barrier layer is formed by a dip coating method, a spray spraying method, a printing method, or a catalytic metal dissolution and removal method. Can do. Among these, the printing method is particularly useful when the reforming catalyst / support is a flat plate type. The method for dissolving and removing the catalyst metal can be performed by eluting the metal component from the surface of the reforming catalyst / support using a solvent. In the case of a reforming catalyst / support in which the reforming catalyst / support is composed of Ni-YSZ cermet, the surface portion of Ni can be eluted using a solvent.

  Then, a hydrogen permeable film is formed on the surface of the barrier layer formed on the reforming catalyst / support. As the hydrogen permeable film, a film that selectively permeates hydrogen from the reformed gas is used, but a metal film such as a Pd film or a Pd alloy film is preferably used. The metal film is supported on the surface of the barrier layer by a plating method, a vapor deposition method, or other appropriate methods.

S Space in which gas can flow between the inner tube and the reforming catalyst / support 11, 21 Raw material gas supply pipe 12, 22 Header 13, 23 Separated high-purity hydrogen outlet pipe 14, 24 Header 15, 25 Off-gas discharge pipe 16 Exhaust gas (burner flame, etc.) discharge pipe

Claims (9)

  A dense hollow support having a hollow portion which is a flow path for the source gas, and a reforming catalyst / support made of a porous material are disposed in close contact with the outer peripheral surface of the dense hollow support, and the reforming catalyst / support is also provided. A hydrogen separation membrane is arranged on the outer peripheral surface of the body, the raw material gas is passed through the hollow portion inside the dense hollow support, and folded at the tip in the flow direction to flow through the reforming catalyst / support. A hydrogen production apparatus characterized in that a reformed gas is produced from a gas and the produced reformed gas is purified by a hydrogen separation membrane to produce high purity hydrogen.   2. The hydrogen production apparatus according to claim 1, wherein the dense hollow support body having the hollow portion is a cylindrical tube made of stainless steel or ceramics.   3. The hydrogen production apparatus according to claim 1, wherein the reforming catalyst / support is made of a sintered body of a mixture of nickel and yttria-stabilized zirconia. 4.   The hydrogen production apparatus according to any one of claims 1 to 3, wherein the hydrogen separation membrane is a Pd membrane or a Pd alloy membrane.   5. The hydrogen production apparatus according to claim 1, wherein a barrier layer is provided between the reforming catalyst / support and the hydrogen separation membrane. 6.   A dense hollow support having a hollow portion which is a flow path for the raw material gas, a reforming catalyst layer disposed on the outer peripheral surface of the dense hollow support, and a hydrogen separation membrane disposed on the outer periphery of the reforming catalyst layer. The reformed gas is generated from the source gas while flowing through the reforming catalyst layer by passing the source gas through the hollow portion inside the dense hollow support and turning back at the tip in the flow direction. A hydrogen production apparatus characterized in that it is purified by a hydrogen separation membrane to produce high purity hydrogen.   The hydrogen production apparatus according to claim 6, wherein the dense hollow support having the hollow portion is a cylindrical tube made of stainless steel or ceramics.   8. The hydrogen production apparatus according to claim 6, wherein the reforming catalyst of the reforming catalyst layer is made of a mixture of nickel and yttria stabilized zirconia. 9. The hydrogen production apparatus according to any one of claims 6 to 8, wherein the hydrogen separation membrane is a Pd membrane or a Pd alloy membrane.

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