JP2014046228A - Method for manufacturing hydrogen separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a hydrogen separator, capable of reducing the occurrence of pin holes in a hydrogen separation metal layer.SOLUTION: A method for manufacturing a hydrogen separator includes: a first step of mixing Pd being a hydrogen separation metal, or metal powder containing the Pd and a metal (e.g., Ag) alloyed with the Pd for improving a hydrogen permeability as the main component with ceramics (e.g., YSZ) powder to make past-like materials; a second step of forming a surface forming layer (77) on support molded body (73) by covering the surface of the porous support molded body (73) before sintering using the past-like materials; and a third step of co-firing the support molded body (73) with the surface forming layer (77), and performing the sintering thereof. Consequently, a porous medium (20) comprising the hydrogen separation metal layer (19) inside is made.

Description

  The present invention relates to a method for producing a hydrogen separator, and more particularly, to a method for producing a hydrogen separator capable of obtaining high-purity hydrogen gas by selecting and separating hydrogen gas from a raw material gas.

  Conventionally, for example, in order to produce hydrogen to be supplied to a fuel cell, a hydrogen separator that selectively extracts only hydrogen from a gas containing hydrogen such as steam reformed gas has been developed. In this hydrogen separator, for example, a hydrogen permeable membrane (hereinafter referred to as a hydrogen separation metal layer) made of palladium (Pd) or the like is formed on the surface of a cylindrical ceramic porous substrate.

  As a technique for producing this type of hydrogen separator, for example, in Patent Documents 1 and 2 below, the surface of the porous support is subjected to nucleation treatment, and then the surface nuclei are removed by acid treatment. A method for producing a porous filled hydrogen separator by forming a hydrogen separation metal layer by Pd plating is disclosed.

  In addition, as a method that does not use the electroless plating method, in Patent Document 3 below, a paste in which Pd ultrafine particles and Ag ultrafine particles are mixed is applied to the surface of a porous support that is a sintered body. Then, a method for forming a hydrogen separation metal layer by baking is disclosed.

JP 2005-13853 A JP 2006-95521 A JP 2001-145824 A

  However, as described in Patent Documents 1 and 2, when the hydrogen separation metal layer is formed by the electroless plating method, the followability of plating with respect to defects (dents and protrusions) on the surface of the porous support is low. In the defective portion, there is a problem that a portion where the plated metal is not filled in the pores, that is, a pinhole is generated.

  In addition, as described in Patent Document 3, in the case where the hydrogen separation metal layer is formed by baking on the sintered support, since the shrinkage of the hydrogen separation metal layer during sintering is suppressed, There is a problem that it is difficult to make the separation metal layer dense and it is not easy to form a hydrogen separation metal layer without pinholes.

In addition, if there is a pinhole in the hydrogen separation metal layer in this way, gas leaks from the pinhole portion, and as a result, the purity of the separated hydrogen is lowered, so that improvement has been demanded.
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a method for producing a hydrogen separator capable of reducing the generation of pinholes in the hydrogen separation metal layer.

(1) As a first aspect, the present invention provides a hydrogen separator manufacturing method for manufacturing a hydrogen separator including a hydrogen separator metal layer that allows only hydrogen to permeate inside a porous body. A first step of preparing a paste-like material by mixing Pd, or a metal powder mainly composed of Pd and a metal that is alloyed with Pd and improving hydrogen permeability, and a ceramic powder; A second step of forming a surface forming layer on the support molded body by covering the surface of the porous support molded body before sintering using the paste-like material produced in the first step; A third step of producing the porous body having the hydrogen separation metal layer therein by co-firing and sintering the support molded body and the surface forming layer formed in the second step; It is characterized by having

  In the first aspect, in the first step, “a metal powder containing Pd as a main component” or “a metal containing, as a main component, a metal that is alloyed with Pd and Pd to improve hydrogen permeability (eg, Ag)”. "Powder" and ceramic powder are mixed to produce a paste-like material, and in the second step, this paste-like material is used to form a surface forming layer on the surface of the support body (before sintering) In the third step, the support molded body and the surface forming layer are co-fired to produce a porous body having a hydrogen separation metal layer therein.

  That is, in the first aspect, since the support forming body and the surface forming layer (for example, pre-sintered before sintering) are co-fired and sintered, the surface forming layer has a shrinking action due to the firing of the support. work. Therefore, as compared with the conventional baking method, the hydrogen separation metal layer can be easily made dense, so that a hydrogen separation metal layer with few pinholes can be realized. Even on the surface of the support that becomes a defect when the surface-forming layer is formed after sintering, the surface defect is not apparent at the time of the support molded body. By forming the surface forming layer on the support molded body by co-sintering, formation of defects in the surface forming layer can be suppressed. As a result, defects in the hydrogen separation metal layer formed on the surface formation layer, that is, gas leakage can be reduced, and the purity of the separated hydrogen can be increased.

  (2) In the present invention, as a second aspect, the metal constituting the hydrogen separation metal layer is supplied to the hydrogen separation metal layer of the porous body produced by the third step by electrolytic plating. Features.

  In the second aspect, since the metal (which constitutes the hydrogen separation metal layer) is supplied by electrolytic plating to the hydrogen separation metal layer produced by the third step, the hydrogen separation metal layer can be made more dense. Thereby, generation | occurrence | production of a pinhole can be reduced further.

  (3) In the present invention, as a third aspect, the electrolytic plating is used to supply a metal for an alloy that is alloyed with Pd to improve the hydrogen permeability to the hydrogen separation metal layer, and is heated at a predetermined alloying temperature. By doing so, the Pd and the alloy metal are alloyed.

  In the third aspect, since the hydrogen separation metal layer is formed by alloying Pd and an alloy metal (for example, Ag), high hydrogen permeability can be secured and the characteristics of the alloy can be exhibited. For example, in the case of a PdAg alloy, hydrogen embrittlement can be suppressed.

  (4) In the fourth aspect of the present invention, in the electrolytic plating, an electrolyte is supplied to one side of the hydrogen separation metal layer, and the hydrogen is supplied from the side where the electrolyte is supplied via the electrolyte. By supplying electrons to the hydrogen separation metal of the separation metal layer and supplying a plating solution to the other side of the hydrogen separation metal layer, a plating film is formed on the plating solution supply side of the hydrogen separation metal layer. It is characterized by that.

In the fourth aspect, since the internal power feeding type electrolytic plating is performed, gas leakage can be reduced as compared with the conventional electrolytic plating.
That is, in this internal power feeding type electroplating, an electrolytic solution is supplied to one side of the porous body, a plating solution is supplied from the other side, and electrons are supplied to the base metal via the electrolytic solution to perform electrolysis. Since plating is performed, it is not necessary to form a surface film on the surface of the porous body as in the prior art and to supply power by providing a contact or clipping the surface film. Therefore, the surface film is not damaged, and therefore no gas leak occurs due to the damage of the surface film. Therefore, high purity hydrogen can be obtained.

  Conventionally, an electroless plating method has been used for forming the hydrogen separation metal layer, and this electroless plating has a demerit that it is poor in stability, but it is necessary to use the electroless plating method by this method. There is also an advantage that the manufacturing process can be further stabilized.

  Furthermore, in conventional electrolytic plating, since power is supplied through the surface film, the thickness of the hydrogen separation metal layer in the vicinity of the surface film becomes thicker than other parts, and there is a problem that the hydrogen permeability decreases. In the power feeding method, the thickness of the hydrogen separation metal layer can be made uniform, so that there is an effect that there is no portion that sacrifices the hydrogen permeation performance.

  (5) In the present invention, as a fifth aspect, in the method for producing a hydrogen separator comprising a hydrogen separation metal layer having a porous body with a hydrogen separation metal layer that allows only hydrogen to permeate, the hydrogen separation metal The first step of preparing a paste-like material by mixing a metal powder mainly composed of a metal that is alloyed with Pd and improving the hydrogen permeability and a ceramic powder, and the first step. A paste-like material is used to cover the surface of the porous support molded body before sintering, thereby forming a surface forming layer on the support molded body, and the second process. The third step of producing the porous body having the metal layer for the alloy therein by co-firing and sintering the formed support body and the surface forming layer, and the porous material produced by the third step Alloy metal layer On the other hand, the fourth step of supplying Pd by electrolytic plating and the alloy metal layer to which Pd is supplied in the fourth step are heated at a predetermined alloying temperature, whereby the Pd and the alloy are heated. And a fifth step of forming a hydrogen separation metal layer by alloying the working metal.

  In the fifth aspect, in the first step, a metal powder mainly composed of a metal (for example, Ag) that is alloyed with Pd to improve hydrogen permeability and ceramic powder are mixed to prepare a paste-like material. In the second step, the paste-like material is used to form a surface forming layer on the support molded body (before sintering), and in the third step, the support molded body and the surface forming layer are combined. Firing is performed to produce a porous body having an alloy metal layer therein, and in the fourth step, Pd is supplied to the porous alloy metal layer by electrolytic plating, and in the fifth step. The alloy metal layer supplied with Pd is alloyed to form a hydrogen separation metal layer.

  That is, in the fifth aspect, since the support molded body (pre-sintered, for example, pre-sintered) and the surface forming layer are co-fired and sintered, the sintering behavior can be made uniform. Therefore, as compared with the conventional baking method, the hydrogen separation metal layer can be easily made dense, so that a hydrogen separation metal layer with few pinholes can be realized. As a result, since gas leakage can be reduced, a remarkable effect is achieved in that the purity of separated hydrogen can be increased.

  Moreover, in this 5th aspect, since hydrogen separation metal layer is formed by alloying Pd and the metal for alloys (for example, Ag), high hydrogen permeability can be secured and the characteristics of the alloy can be exhibited. For example, in the case of a PdAg alloy, hydrogen embrittlement can be suppressed.

  (6) In the sixth aspect of the present invention, in the electrolytic plating, an electrolyte is supplied to one side of the alloy metal layer, and the alloy is supplied from the side supplied with the electrolyte via the electrolyte. A plating film is formed on the plating solution supply side of the alloy metal layer by supplying electrons to the alloy metal of the alloy metal layer and supplying a plating solution to the other side of the alloy metal layer. It is characterized by that.

  In the sixth aspect, since the internal power feeding type electroplating is performed, the same effects as in the fourth aspect are achieved.

It is sectional drawing which fractures | ruptures and shows the hydrogen separator in Example 1 along an axial direction. It is explanatory drawing which fractures | ruptures and expands a part of hydrogen separator in Example 1 along an axial direction. It is explanatory drawing which fractures | ruptures a part of hydrogen separator in Example 1, 2 along an axial direction, and expands it further typically. It is sectional drawing which fractures | ruptures and shows the hydrogen separator in Example 1 along an axial direction. It is explanatory drawing which shows the manufacture procedure etc. of a ceramic sintered compact among the manufacturing methods of the hydrogen separator of Example 1. FIG. It is explanatory drawing which shows the manufacturing procedure etc. of a porous layer among the manufacturing methods of the hydrogen separator of Example 1. FIG. It is explanatory drawing which shows the test apparatus for performing the hydrogen separation test of the hydrogen separator in Example 1. FIG. It is explanatory drawing which fractures | ruptures a part of hydrogen separator in Example 3 along an axial direction, and shows the manufacturing method of the hydrogen separator. It is explanatory drawing which shows the electroplating of an internal electric power feeding system among the manufacturing methods of the hydrogen separator of Example 3. FIG. It is explanatory drawing which fractures | ruptures a part of hydrogen separator in Example 4, 5 along an axial direction, and shows the manufacturing method of the hydrogen separator. It is explanatory drawing which fractures | ruptures a part of hydrogen separator in Example 6, 7 along an axial direction, and shows the manufacturing method of the hydrogen separator.

Hereinafter, embodiments of the present invention will be described.
<Configuration of hydrogen separator>
The porous body is made of a porous material that can permeate a gas containing hydrogen in whole or in part, and ceramic powder is used as this material. Examples of the ceramic include yttria stabilized zirconia, stabilized zirconia, alumina, magnesia, ceria, doped ceria, and a mixture thereof.

  Further, a hydrogen separator may be configured by joining a dense portion that does not transmit gas to, for example, an axial end portion of the porous body. Here, “without gas permeability” is only required to prevent permeation of the raw material gas from which hydrogen is separated, and includes, for example, a density with a relative density of 70% or more.

  Note that ceramic powder is used as a material constituting the dense portion. Examples of the dense ceramic include yttria stabilized zirconia, stabilized zirconia, alumina, magnesia, ceria, doped ceria, and mixtures thereof.

  Examples of the material constituting the hydrogen separation metal layer include Pd, PdCu alloy, PdAg alloy, and PdAu alloy. Accordingly, examples of the metal powder for forming the hydrogen separation metal layer include Pd powder, Cu powder, Ag powder, Au powder, PdCu alloy powder, PdAg alloy powder, and PdAu alloy powder. Cu, Ag, and Au are not used alone, but are alloys for use in alloying with Pd having hydrogen permeability.

Therefore, Pd and Pd alloys (that is, PdCu alloys, PdAg alloys, and PdAu alloys) are used as the metals used in the paste-like material and the metals used in the electrolytic plating (for example, internal power feeding type electrolytic plating). A metal is mentioned. That is, Ag, Cu, Au, Pd is mentioned.

From the viewpoint of suppressing hydrogen embrittlement, a PdAg alloy is preferable to Pd alone. In the case of a hydrogen separator used at a high temperature (for example, 450 ° C. or higher), a PdAg alloy is desirable.
<Configuration of electrolytic plating>
As the electrolyte (solute) of the electrolytic solution, NaCl, KCl, NaBr, MgCl ₂ , CaCl ₂ , (CH ₃ ) ₄ NClO ₄ , (CH ₃ ) ₄ NPF _6, or the like that can be used can be used. . In addition, as this solute, a thing with higher solubility and higher electrical conductivity is preferable.

  As the solvent of the electrolytic solution, water, methanol, ethanol, propanol, butanol, toluene, xylene, acetonitrile, dichloromethane, chloroform, butanone, ether, DMSO (Dimethyl sulfoxide), or the like that can dissolve the electrolyte is used. A wide potential window is preferable.

As the concentration of the electrolyte (solute concentration), for example, a range of 1 mmol / L to 10 mol / L can be employed.
The concentration of the plating solution and the metal compound in the solution can be appropriately selected depending on the coating material desired to be formed.

For example, for silver (Ag), a silver cyanide plating solution (silver cyanide concentration: 15 to 30 g / L) and a non-cyanide silver plating solution (silver compound concentration: 10 to 40 g / L) can be employed.
For copper (Cu), copper sulfate plating solution (copper sulfate concentration: 60 to 250 g / L), copper pyrophosphate plating solution (copper pyrophosphate concentration: 65 to 105 g / L), copper cyanide plating solution (copper cyanide) Concentration: 20 to 80 g / L) can be employed.

For gold (Au), a gold cyanide plating solution (potassium gold cyanide concentration: 1 to 12 g / L) and an acidic gold plating solution (potassium gold cyanide concentration: 1 to 30 g / L) can be employed.
In the case of palladium (Pd), an ammonia alkaline palladium plating solution (palladium compound concentration: 5 to 40 g / L) can be employed.

What is necessary is just to take bath temperature suitable for each plating solution as the bath temperature in the case of the said electroplating, for example, the range of 0-70 degreeC.
For example, 10-30 ° C. for cyan silver plating solution, 15-35 ° C. for non-cyan silver plating solution, 10-30 ° C. for copper sulfate plating solution, 50-60 ° C. for copper pyrophosphate plating solution, cyan The temperature is 40 to 70 ° C. for a copper halide plating solution, 50 to 70 ° C. for a gold cyanide plating solution, 10 to 60 ° C. for an acidic gold plating solution, and 10 to 70 ° C. for a palladium plating solution.

What is necessary is just to select suitably the electric current conditions (current density) in the case of the said electroplating according to the metal to plate and a desired film thickness. For example, if silver 0.01~3A / dm ^2, if copper 0.01~6A / dm ^2, if gold 0.01~9A / dm ^2, if palladium 0.01~9A / dm ² The range is appropriate.

Below, the Example of the manufacturing method of the hydrogen separator which selectively isolate | separates hydrogen from source gas is described.
In this embodiment, a hydrogen separation metal layer made of Pd is formed using a Pd ceramic mixed paste to produce a hydrogen separator.

a) First, the configuration of the hydrogen separator in this example will be described.
As shown in FIG. 1, the hydrogen separator 1 in this embodiment is a member that separates hydrogen from a raw material gas, and the distal end side (upper side in the figure) is closed and the proximal end side (lower side in the figure) is opened. Having a test tube shape.

  The hydrogen separator 1 is provided with a test tube-shaped hydrogen separator 3 mainly made of a porous ceramic and having a function of separating hydrogen, and the open base end thereof has gas permeability. There is provided a cylindrical dense portion 5 made of a dense ceramic having no strength and high strength. Each configuration will be described below.

  The hydrogen separation unit 3 selectively separates hydrogen from a raw material gas (for example, a reformed gas generated by bringing natural gas and water vapor into contact with a catalyst) introduced into a central hole 7 at the axial center thereof, thereby separating the hydrogen. It is a member supplied to the outer peripheral side of the part 3.

  As shown in an enlarged view in FIG. 2, the hydrogen separation unit 3 is integrally formed from a test tubular porous support 9 with one end closed and a porous layer 11 covering the outer surface of the porous support 9. It is configured.

  Among these, the porous support 9 is a support made of a porous ceramic made of yttria-stabilized zirconia (YSZ), that is, a support having a role of supporting the porous layer 11 while having air permeability. The porous support 9 has a porosity of 40%, for example, and has a structure capable of transmitting the source gas.

  On the other hand, the porous layer 11 is a coating layer made of porous ceramics made of YSZ, and similarly has a structure through which the raw material gas can permeate. Specifically, the porous layer 11 includes a first porous layer 13 that covers the outer surface of the porous support 9, and a second porous member that covers the outer surface of the first porous layer 13 (at least hydrogen gas is permeable). The material layer 15 is integrally formed.

  As further enlarged in FIG. 3, the first porous layer 13 is a structure 16 made of YSZ in which a large number of pores 17 are formed. Inside the pores 17, A hydrogen permeable metal (Pd in this embodiment) is filled. This hydrogen permeable metal is a metal that separates hydrogen from the source gas by selecting and allowing only hydrogen from the source gas to permeate.

  That is, the portion inside the first porous layer 13 that is filled with Pd and covers the entire outside of the porous support 9 in the form of a layer is the hydrogen separation metal layer 19 that is a hydrogen permeable membrane. As will be described later, the hydrogen separation metal layer 19 is formed simultaneously with the formation of the first porous layer 13.

  On the other hand, since the second porous layer 15 extends outside the hydrogen separation metal layer 19, contaminants (for example, Fe) that damage the hydrogen separation metal layer 19 from the outside adhere to the hydrogen separation metal layer 19. To prevent that.

In the hydrogen separator 3, a porous ceramic structure portion, that is, a ceramic portion of the porous support 9 and the porous layer 11 is referred to as a porous body 20.
As shown in FIG. 1, the dense portion 5 is a cylindrical ceramic body made of YSZ and is sufficiently dense to prevent gas permeation, and its strength is greater than that of the hydrogen separation portion 3. Has been.

b) Next, a hydrogen separator equipped with the hydrogen separator 1 will be briefly described.
As shown in FIG. 4, the hydrogen separator 21 includes a hydrogen separator 1, a cylindrical mounting bracket 23 into which the open end side of the hydrogen separator 1 is inserted, an outer peripheral surface of the hydrogen separator 1, and the mounting bracket 23. A cylindrical sealing member 25 disposed between the inner peripheral surface, a cylindrical pressing metal member 27 that is externally fitted to the hydrogen separator 1 and presses the distal end side of the sealing member 25, and is externally fitted to the pressing metal member 27. And a cylindrical fixing metal 29 that is screwed into the mounting metal 23.

  The mounting bracket 23 includes a distal end side cylindrical portion 31 and a flange portion 33, and a through hole (hollow portion) 35 serving as a flow path for the source gas is formed at the shaft center. The end portion on the base end side of the hydrogen separator 1 is accommodated. The fixing bracket 29 includes a pressing plate 37 and a cylindrical portion 39. The pressing fitting 27 is disposed adjacent to the seal member 25 in a space 43 between the mounting fitting 23 and the hydrogen separator 1. The seal member 25 is made of expanded graphite, and is disposed adjacent to the pressing fitting 27 in the space 43.

Here, a metal joint 40 is constituted by the mounting bracket 23, the pressing bracket 27, and the fixing bracket 29 attached to the hydrogen separator 1.
In the hydrogen separator 21 (specifically, the center hole 7 of the hydrogen separator 1), an inner tube 45 is arranged, and the raw gas is supplied into the hydrogen separator 1 through the inner tube 45.

  Therefore, hydrogen is separated from the source gas supplied from the outside into the hydrogen separator 1 through the inner tube 45 in the hydrogen separator 3, and the hydrogen is discharged to the outer peripheral side of the hydrogen separator 3. On the other hand, the remaining gas (off-gas) that is not separated is discharged to the outside from the base end side of the hydrogen separator 1 along the outer periphery of the inner tube 45.

  In addition, in FIG. 4, although the example which supplies raw material gas into the inside of the hydrogen separator 1 was described, conversely, without using the intubation 45, source gas was supplied to the outer side of the hydrogen separator 1, Hydrogen may be taken out from the inside of the hydrogen separator 1.

c) Next, the manufacturing method of the hydrogen separator 1 of a present Example is demonstrated.
<First powder filling step>
In the present embodiment, press molding is performed using a mold 51 as shown in FIG. A cylindrical internal hole 55 corresponding to the outer shape of the hydrogen separator 1 is formed at the axial center of the cylindrical rubber mold 53 of the mold 51, and hydrogen separation is performed at the axial center of the internal hole 55. A cylindrical (test tube shape) center pin 57 corresponding to the shape of the center hole 7 of the body 1 is provided upright. As a result, a substantially cylindrical mold hole 59 is formed.

Therefore, in this example, the YSZ granulated powder was filled in the mold hole 59 of the rubber mold 53 as a material for forming the dense portion 5, and the cylindrical dense portion forming portion 61 was produced.
<Second powder filling step>
Next, as shown in FIG. 5 (b), similarly, the pore former is used as a material for forming the porous support 9 on the dense portion forming portion 61 in the mold hole 59 of the rubber mold 53. As above, YSZ granulated powder added with 48% by volume of organic beads was filled.
<Pressurization process>
Next, as shown in FIG. 5C, the upper mold 63 was fixed to the upper part of the rubber mold 53. The upper mold 63 is formed with a concave portion 65 having a shape corresponding to the tip of the porous support 9. By fitting the concave portion 65, the porous die having the same shape as the porous support 9 is formed. The formation part 67 is produced.

And in this state, by pressing from the outer peripheral side of the rubber mold 53 and press-molding, a bottomed cylindrical shaped body 69 corresponding to the shape of the hydrogen separator 1 as shown in FIG. . <Temporary firing process>
Next, the bottomed cylindrical molded body 69 taken out from the rubber mold 53 is degreased, and then calcined at 1000 ° C., so that as shown in FIG. A ceramic pre-fired body 75 having an outer diameter of φ10 mm and a length of 300 mm integrated with the porous support 73 was obtained.
<Porous layer forming step>
Next, as shown in an enlarged view in FIG. 6 (b), a PdYSZ paste is produced using a material of Pd: YSZ = 50: 50 (volume ratio), and the temporary calcined body 75 of the ceramic calcined body 75 is prepared by dip coating. The entire outer surface of the fired porous support 73 was covered with a PdYSZ paste to form an unfired first porous layer 77.

  Next, as shown in FIG. 6C, a YSZ paste is prepared using YSZ, and the entire outer surface of the unfired first porous layer 77 is covered with the YSZ paste by dip coating, A second porous layer 79 was formed.

The temporarily fired porous support 73 corresponds to the support molded body of the present invention, and the unfired first porous layer 77 corresponds to the surface forming layer of the present invention.
<Baking process>
Next, the ceramic temporary fired body 75 on which the unfired first porous layer 77 and the unfired second porous layer 79 are formed is fired (co-fired) at 1400 ° C., so that the hydrogen separator of this example is used. 1 was obtained.

As shown in FIG. 3, the unfired first porous layer 77 forms a porous structure 16 made of YSZ as shown in FIG. 3, and hydrogen is formed in the pores 17 of the structure 16. A structure in which the permeable metal is packed is formed, whereby the hydrogen separation metal layer 19 having a thickness of, for example, 5 μm is formed.
<Assembly method of hydrogen separator 21>
Then, as shown in FIG. 4, the hydrogen separator 1 was provided with a metal joint 40 or the like attached to the hydrogen separator 1.

Specifically, the sealing member 25 and the pressing member 27 were fitted in the mounting member 23 in this order.
Next, the open end side of the hydrogen separator 1 was inserted so as to pass through the through hole of the pressing fitting 27 and the through hole of the sealing material 25, and the end of the hydrogen separator 1 was fitted into the mounting fitting 23.

Next, the fixing bracket 29 was externally fitted from the front end side of the hydrogen separator 1 and tightened with screws, and the pressing bracket 27 was tightened with the fixing bracket 29 to complete the hydrogen separator 21.
d) Next, an experimental example performed using the hydrogen separator 21 of this example will be described.

  As shown in FIG. 7, the hydrogen separator 21 of this example is accommodated in a cylindrical stainless steel reaction vessel 83, and the temperature is 550 ° C. at the outer periphery of the hydrogen separator 21 (that is, outside the hydrogen separator 1). A hydrogen-containing gas having a pressure of 0.8 MPaG (specifically, a hydrogen-containing gas produced by a reforming reaction using natural gas containing about 25% hydrogen and water vapor as raw materials), while the central hole 7 of the hydrogen separator 1 is introduced. A hydrogen separation test was conducted in which high-purity hydrogen was extracted into the center hole 7 at a pressure of 0.0 MPaG.

As a result, hydrogen having a purity of 99.99% or more was obtained. Further, even when a long-time test over 1000 hours was performed, there was no decrease in hydrogen purity and the durability was excellent.
e) In this example, the PdYSZ paste is used to form the unfired first porous layer 77 on the surface of the ceramic temporary fired body 75, and the YSZ paste is used to form the unfired first porous layer 77 on the surface. The unfired second porous layer 79 is formed, and the ceramic preliminary fired body 75 (with the unfired first porous layer 77 and the unfired second porous layer 79) is co-fired to form the first porous A hydrogen separator 1 having a hydrogen separation metal layer 19 in the mass layer 13 is produced.

  Thereby, the sintering behavior of the unfired first porous layer 77, the unfired second porous layer 79, and the ceramic pre-fired body 75 can be made uniform. Therefore, as compared with the conventional baking method, the hydrogen separation metal layer 19 can be easily made dense, so that the hydrogen separation metal layer 19 with few pinholes can be realized. As a result, since gas leakage can be reduced, a remarkable effect is achieved in that the purity of separated hydrogen can be increased.

Next, although the manufacturing method of the hydrogen separator of Example 2 is demonstrated, description of the content similar to the said Example 1 is abbreviate | omitted.
In addition, since the basic structure of the ceramic in the hydrogen separator of the present embodiment is the same as that of the first embodiment, the following description will be made with reference to FIG. In addition, similar members and the like will be described using similar numbers.

  In this embodiment, a PdAg metal layer is formed using a PdAg ceramic mixed paste, and then an alloying of Pd and Ag is performed to form a hydrogen separation metal layer made of a PdAg alloy.

a) First, the configuration of the hydrogen separator of this example will be described.
As shown in the enlarged view of FIG. 3, the hydrogen separator 91 of this example is similar to Example 1 in that the test tube-shaped porous support 9 and its outer surface (right side of the figure) The porous layer 11 includes a first porous layer 13 and a second porous layer 15.

  In particular, in this embodiment, a hydrogen separation metal layer 93 that is a PdAg alloy layer made of a PdAg alloy is formed on the entire first porous layer 13. The hydrogen separation metal layer 93 has a thickness of 5 μm.

b) Next, the manufacturing method of the hydrogen separator 91 of a present Example is demonstrated.
In this example, as in Example 1, the “first powder filling step”, the “second powder filling step”, the “pressing step”, the “temporary firing step”, the “porous layer forming step”, “ The hydrogen separator 91 as shown in FIG. 3 was obtained by the “firing step”.

In the “porous layer forming step”, a PdAgYSZ paste was prepared using a material of Pd: Ag: YSZ = 35: 15: 50 (volume ratio).
The hydrogen separator 91 was attached with a metal joint 40 and the like in the same manner as in Example 1 (see FIG. 4).

c) Next, experimental examples will be described.
Using the same experimental apparatus as in Example 1 (see FIG. 7), under the same experimental conditions (temperature, pressure), the same hydrogen-containing gas was introduced into the outer periphery of the hydrogen separator 21 of this example, A hydrogen separation test was conducted in which high-purity hydrogen was taken out from the cylinder.

As a result, hydrogen having a purity of 99.99% or more was obtained. Further, even when a test for a long time (1000 hours) was performed, the purity of hydrogen did not decrease and the durability was excellent.
d) In this example, the PdAgYSZ paste is used to form the unfired first porous layer 77 on the surface of the ceramic temporary fired body 75, and the YSZ paste is used to form the unfired first porous layer 77 on the surface. The unfired second porous layer 79 is formed, and the ceramic preliminary fired body 75 (with the unfired first porous layer 77 and the unfired second porous layer 79) is co-fired to form the first porous A hydrogen separator 91 having a hydrogen separation metal layer 93 on the mass layer 13 is manufactured.

  Therefore, according to the present embodiment, the hydrogen separation metal layer 93 can be easily made dense as in the first embodiment, so that the hydrogen separation metal layer 93 with few pinholes can be realized.

  In particular, in this embodiment, since the hydrogen separation metal layer 93 is made of PdAg, there is an advantage that hydrogen embrittlement can be reduced.

Next, although the manufacturing method of the hydrogen separator of Example 3 is demonstrated, description of the content similar to the said Example 1 is abbreviate | omitted. In addition, the same number is used and demonstrated to the same member.
In this example, after forming a hydrogen separation metal layer made of Pd using a Pd ceramic mixed paste, the thickness of the hydrogen separation metal layer is further increased by electrolytic Pd plating.

a) First, the configuration of the hydrogen separator of this example will be described.
As shown in the enlarged view of the main part in FIG. 8 (b), the hydrogen separator 101 of this example is similar to Example 1, in that the test tube-shaped porous support 103 and its outer surface (same as the same). And the porous layer 105 is composed of a first porous layer 109 and an outer second porous layer 111.

  In particular, in this embodiment, the first porous layer 109 is provided with a Pd metal layer 113 (formed from a paste containing Pd), and a central hole outside the Pd metal layer 113, that is, in the second porous layer 111. The Pd plating metal layer 115 formed by electrolytic Pd plating is provided on the 107 side (inner side).

Note that the Pd metal layer 113 and the Pd plating metal layer 115 are integrated with each other to form a hydrogen separation metal layer 117.
b) Next, the manufacturing method of the hydrogen separator 101 of a present Example is demonstrated.

In this example, as in Example 1, the “first powder filling step”, the “second powder filling step”, the “pressure step”, the “temporary firing step”, and the “porous layer forming step” A ceramic pre-fired body 75 covered with the unfired first porous layer 77 and the unfired second porous layer 79 as shown in FIG. 6 was produced.
<Baking process>
Next, as in Example 1, the ceramic temporary fired body 75 provided with the unfired first porous layer 77 and the unfired second porous layer 79 was fired at 1400 ° C., so that FIG. A ceramic sintered body 121 shown partially enlarged in FIG.

The ceramic sintered body 121 includes a porous layer 105 composed of a first porous layer 109 and a second porous layer 111 formed so as to cover the surface of the porous support 103.
That is, since Pd is contained in the unfired first porous layer 77, the first porous layer 109 (which is obtained by firing the unfired first porous layer 77) has its own pore 123. It has a structure filled with Pd which is a hydrogen permeable metal. The portion filled with Pd is a Pd metal layer 113 having a film thickness of 3 μm, which becomes the base portion of the hydrogen separation metal layer 117.
<Electrolytic plating process>
Next, as shown in FIG. 9, an internal power feeding type plating apparatus 124, a central hole 107 (and thus a ceramic sintered body) of a porous support 103 provided with a porous layer 105 (including a Pd metal layer 113 inside). Into 121 central hole 107), a 6.0 mol / L NaCl aqueous solution (NaCl saturated aqueous solution) was introduced as an electrolyte.

  Further, after inserting the feeding electrode 125 into the NaCl electrolyte, the ceramic sintered body 121 was set in an electrolytic Pd plating solution (concentration: 10 g / L) having a bath temperature of 30 ° C. in which the counter electrode 127 was arranged in advance. . The electrolytic Pd plating solution is supplied to the outside of the porous layer 105.

Then, constant current electrolytic plating was performed for 2.0 minutes at a current value (current density) of 0.5 A / dm ² , pd was deposited in the pores 129 and the like of the second porous layer 111, and the Pd metal layer 113 was A Pd plating metal layer 115 having a thickness of 1.5 μm, which is a Pd plating film, was formed. As a result, a hydrogen separation metal layer 117 in which the Pd metal layer 113 and the Pd plating metal layer 115 were integrated was formed.

  In this electrolytic Pd plating, the Pd metal layer 113 is applied to the Pd metal layer 113 via the electrolytic solution supplied to the central hole 107 inside the porous support 103 (and thus supplied to the pores 130 of the porous support 103). Electrons are supplied, and the plating metal (Pd in this case) is supplied to the outside of the Pd metal layer 113 through the electrolytic Pd plating solution supplied to the outside of the porous layer 105.

  Through these steps, a hydrogen separator 101 as shown in FIG. 8B was completed. Then, a metal joint 40 or the like was attached to the hydrogen separator 101 in the same manner as in Example 1 (see FIG. 4) to obtain a hydrogen separator 21.

c) Next, experimental examples will be described.
Using the same experimental apparatus as in Example 1 (see FIG. 7), under the same experimental conditions (temperature, pressure), the same hydrogen-containing gas was introduced into the outer periphery of the hydrogen separator 21 of this example, A hydrogen separation test was conducted in which high-purity hydrogen was taken out from the cylinder.

As a result, hydrogen having a purity of 99.99% or more was obtained. Further, even when a test for a long time (1000 hours) was performed, the purity of hydrogen did not decrease and the durability was excellent.
d) In this example, the PdYSZ paste is used to form the unfired first porous layer 77 on the surface of the ceramic temporary fired body 75, and the YSZ paste is used to form the unfired first porous layer 77 on the surface. The unfired second porous layer 79 is formed, and the ceramic preliminary fired body 75 (with the unfired first porous layer 77 and the unfired second porous layer 79) is co-fired to form the first porous A ceramic sintered body 121 having a Pd metal layer 113 on the mass layer 109 is manufactured.

  Thereafter, a Pd plating metal layer 115 was formed on the outside of the Pd metal layer 113 by electrolytic Pd plating of an internal power feeding method to form a hydrogen separation metal layer 117, whereby the hydrogen separator 101 was manufactured.

  Therefore, according to the present embodiment, the hydrogen separation metal layer 117 can be easily made dense as in the first embodiment, so that the hydrogen separation metal layer 117 with few pinholes can be realized.

  In particular, in this embodiment, since the Pd plating metal layer 115 is formed by electrolytic Pd plating of the internal power feeding method, the thickness of the hydrogen separation metal layer 117 is increased and becomes denser, so that the pinhole can be greatly reduced. There is.

Next, although the manufacturing method of the hydrogen separator of Example 4 is demonstrated, description of the content similar to the said Example 3 is abbreviate | omitted. In addition, the same number is used and demonstrated to the same member.
In this example, after a Pd metal layer was formed using a Pd ceramic mixed paste, electrolytic Ag plating was performed to form an Ag plating metal layer, and then Pd and Ag were alloyed to form PdA.
A hydrogen separating metal layer made of a g alloy is formed.

a) First, the configuration of the hydrogen separator of this example will be described.
As shown in the enlarged view of FIG. 10 (c), the hydrogen separator 131 of this example has a test tube-shaped porous support 133 and its outer surface (same as in Example 3). And the porous layer 135 includes a first porous layer 139 and a second porous layer 141.

In particular, in this embodiment, a hydrogen separation metal layer 143 made of a PdAg alloy is formed on the entire first porous layer 139 and the central hole 137 side (inside) in the second porous layer 141.
b) Next, a method for producing the hydrogen separator 131 of this embodiment will be described.

  In this example, as in Example 3, the “first powder filling step”, the “second powder filling step”, the “pressurizing step”, the “temporary firing step”, the “porous layer forming step”, “ As shown in FIG. 10A, a ceramic sintered body 145 was obtained by the “firing step”.

In the “porous layer forming step”, a PdYSZ paste was prepared using a material of Pd: YSZ = 40: 60 (volume ratio).
The ceramic sintered body 145 includes a porous layer 135 composed of a first porous layer 139 and a second porous layer 141 formed so as to cover the surface of the porous support 133.

Among these, Pd is filled in the pores 147 of the first porous layer 139, thereby forming a Pd metal layer 149 having a thickness of 3.0 μm (which will later become a part of the hydrogen separation metal layer 143). Has been.
<Electrolytic plating process>
As shown in FIG. 10 (b), an internal feeding type plating apparatus 124 (see FIG. 9) similar to that used in the third embodiment is used. A NaCl aqueous solution (NaCl saturated aqueous solution) having a concentration of 6.0 mol / L was introduced into the central hole 137) of the bonded body 145 as an electrolytic solution.

  In addition, after inserting the feeding electrode 125 (see FIG. 9) into the NaCl electrolyte, the ceramic sintered body 145 is electroplated with an electrolytic Ag plating solution having a bath temperature of 30 ° C. in which the counter electrode 127 (see FIG. 9) is arranged in advance. (Aqueous solution: concentration 50 g / L).

Then, constant current electrolytic plating was performed for 2.0 minutes at a current value of 0.30 A / dm ² , and an Ag plating metal layer 155 having a thickness of 1.0 μm was formed on the Pd metal layer 149 in the pores 153 of the porous layer 135. Formed.

  Thereafter, heat treatment is performed at 750 ° C. in nitrogen to alloy Pd of the Pd metal layer 149 and Ag of the Ag plating metal layer 155, and as shown in FIG. 10C, is made of a PdAg alloy having a thickness of 4.0 μm. A hydrogen separation metal layer 143 was obtained.

  Through these steps, the hydrogen separator 131 was completed. The hydrogen separator 131 was attached with a metal joint 40 and the like in the same manner as in Example 3 (see FIG. 4).

c) Next, experimental examples will be described.
Using the same experimental apparatus as in Example 3 (see FIG. 7), under the same experimental conditions (temperature, pressure), the same hydrogen-containing gas was introduced into the outer periphery of the hydrogen separator 21 of this example, A hydrogen separation test was conducted in which high-purity hydrogen was taken out from the cylinder.

As a result, hydrogen having a purity of 99.99% or more was obtained. Further, even when a test for a long time (1000 hours) was performed, the purity of hydrogen did not decrease and the durability was excellent.
d) In this example, the PdYSZ paste is used to form the unfired first porous layer 77 on the surface of the ceramic temporary fired body 75, and the YSZ paste is used to form the unfired first porous layer 77 on the surface. The unfired second porous layer 79 is formed, and the ceramic preliminary fired body 75 (with the unfired first porous layer 77 and the unfired second porous layer 79) is co-fired to form the first porous A ceramic sintered body 145 having a Pd metal layer 149 on the quality layer 139 is manufactured.

  Thereafter, an Ag plating metal layer 155 is formed on the outside of the Pd metal layer 149 by electrolytic Ag plating of an internal power feeding method, and Pd and Ag are alloyed to produce a hydrogen separation metal layer 143 made of a PdAg alloy. A hydrogen separator 131 was produced.

  Therefore, according to the present embodiment, the hydrogen separation metal layer 143 can be easily made dense as in the case of the third embodiment, so that the hydrogen separation metal layer 143 with few pinholes can be realized.

  In particular, in this embodiment, since the hydrogen-separated metal layer 143 is formed by alloying after forming the Ag-plated metal layer 155 by electrolytic Ag plating of the internal power feeding method, the thickness of the hydrogen-separated metal layer 143 is increased and further increased. Become precise. Therefore, there is an advantage that pinholes can be greatly reduced and hydrogen embrittlement can be reduced.

Next, although the manufacturing method of the hydrogen separator of Example 5 is demonstrated, description of the content similar to the said Example 4 is abbreviate | omitted.
In addition, since the basic structure of the ceramic in the hydrogen separator of the present embodiment is the same as that of Embodiment 4, the following description will be made with reference to FIG. In addition, similar members and the like will be described using similar numbers.

  In this example, after a PdAg ceramic mixed paste is used to form a PdAg alloy layer, electrolytic Ag plating is performed to form an Ag-plated metal layer, and then Pd and Ag are alloyed to form a hydrogen separation composed of PdAg alloy. A metal layer is formed.

a) First, the configuration of the hydrogen separator of this example will be described.
As shown in the enlarged view of FIG. 10 (c), the hydrogen separator 161 of this example has a test tube-shaped porous support 133 and its outer surface ( And the porous layer 135 includes a first porous layer 139 and a second porous layer 141.

In particular, in this embodiment, a hydrogen separation metal layer 143 made of a PdAg alloy is formed on the entire first porous layer 139 and on the central hole 137 side (inside) in the second porous layer 141.
b) Next, the manufacturing method of the hydrogen separator 161 of a present Example is demonstrated.

  In this example, as in Example 4, the “first powder filling step”, the “second powder filling step”, the “pressurizing step”, the “temporary firing step”, the “porous layer forming step”, “ As shown in FIG. 10A, a ceramic sintered body 145 was obtained by the “firing step”.

In the “porous layer forming step”, a PdAgYSZ paste was prepared using a material of Pd: Ag: YSZ = 45: 5: 50 (volume ratio).
The ceramic sintered body 145 includes a porous layer 135 composed of a first porous layer 139 and a second porous layer 141 formed so as to cover the surface of the porous support 133.

Among these, the PdAg alloy is filled in the pores 147 of the first porous layer 139, thereby forming a 3.7 μm-thick PdAg alloy layer 163 (which later becomes a part of the hydrogen separation metal layer 143). Is formed.
<Electrolytic plating process>
As shown in FIG. 10 (b), an internal power feeding type plating apparatus 124 (see FIG. 9) similar to that used in the fourth embodiment is used. A NaCl aqueous solution (NaCl saturated aqueous solution) having a concentration of 6.0 mol / L was introduced into the central hole 137) of the bonded body 145 as an electrolytic solution.

  In addition, after inserting the feeding electrode 125 (see FIG. 9) into the NaCl electrolyte, the ceramic sintered body 145 is electroplated with an electrolytic Ag plating solution having a bath temperature of 30 ° C. in which the counter electrode 127 (see FIG. 9) is arranged in advance. (Aqueous solution: concentration 50 g / L).

Then, constant current electrolytic plating was performed at a current value of 0.30 A / dm ² for 1.5 minutes, and an Ag plating metal layer 155 having a thickness of 0.8 μm was formed on the PdAg alloy layer 163 in the pores 153 of the porous layer 135. Formed.

Thereafter, heat treatment was performed at 750 ° C. in nitrogen to alloy Pd and Ag, thereby forming a hydrogen separation metal layer 143 made of a PdAg alloy having a thickness of 4.5 μm as shown in FIG.
Through these steps, the hydrogen separator 161 was completed. The hydrogen separator 161 was attached with a metal joint 40 and the like in the same manner as in Example 4 (see FIG. 4).

c) Next, experimental examples will be described.
Using the same experimental apparatus as in Example 4 (see FIG. 7), under the same experimental conditions (temperature, pressure), the same hydrogen-containing gas was introduced into the outer periphery of the hydrogen separator 21 of the present example, A hydrogen separation test was conducted in which high-purity hydrogen was taken out from the cylinder.

As a result, hydrogen having a purity of 99.99% or more was obtained. Further, even when a test for a long time (1000 hours) was performed, the purity of hydrogen did not decrease and the durability was excellent.
d) In this example, the PdAgYSZ paste is used to form the unfired first porous layer 77 on the surface of the ceramic temporary fired body 75, and the YSZ paste is used to form the unfired first porous layer 77 on the surface. The unfired second porous layer 79 is formed, and the ceramic preliminary fired body 75 (with the unfired first porous layer 77 and the unfired second porous layer 79) is co-fired to form the first porous The ceramic sintered body 145 having the PdAg alloy layer 163 in the quality layer 139 is manufactured.

  Thereafter, an Ag plating metal layer 155 is formed on the outside of the PdAg alloy layer 163 by electrolytic Ag plating of an internal power feeding method, and Pd and Ag are alloyed to produce a hydrogen separation metal layer 143 made of a PdAg alloy. A hydrogen separator 161 was produced.

  Therefore, according to the present embodiment, the hydrogen separation metal layer 143 can be easily made dense as in the case of the fourth embodiment, so that the hydrogen separation metal layer 143 with few pinholes can be realized.

  In particular, in this embodiment, since the hydrogen-separated metal layer 143 is formed by alloying after forming the Ag-plated metal layer 155 by electrolytic Ag plating of the internal power feeding method, the thickness of the hydrogen-separated metal layer 143 is increased and further increased. Become precise. Therefore, there is an advantage that pinholes can be greatly reduced and hydrogen embrittlement can be reduced.

Next, although the manufacturing method of the hydrogen separator of Example 6 is demonstrated, description of the content similar to the said Example 5 is abbreviate | omitted. In addition, the same number is used and demonstrated to the same member.
In this example, after a PdAg ceramic mixed paste is used to form a PdAg alloy layer, electrolytic Pd plating is performed to form a Pd-plated metal layer, and then Pd and Ag are alloyed to form a hydrogen separation composed of PdAg alloy. A metal layer is formed.

a) First, the configuration of the hydrogen separator of this example will be described.
As shown in the enlarged view of FIG. 11 (c), the hydrogen separator 171 of this example has a test tube-shaped porous support 173 and its outer surface (same as in Example 5). A porous layer 175 covering the right side of the figure, and the porous layer 175 includes a first porous layer 179 and a second porous layer 181.

In particular, in this embodiment, a hydrogen separation metal layer 183 made of a PdAg alloy is formed on the entire first porous layer 179 and the center hole 177 side (inside) in the second porous layer 181.
b) Next, a method for producing the hydrogen separator 171 of this example will be described.

  In this example, as in Example 5, the “first powder filling step”, the “second powder filling step”, the “pressurizing step”, the “temporary firing step”, the “porous layer forming step”, “ As shown in FIG. 11A, a ceramic sintered body 185 was obtained by the “firing step”.

In the “porous layer forming step”, a PdAgYSZ paste was prepared using a material of Pd: Ag: YSZ = 20: 15: 65 (volume ratio).
The ceramic sintered body 185 includes a porous layer 175 composed of a first porous layer 179 and a second porous layer 181 formed so as to cover the surface of the porous support 173.

Among these, the PdAg alloy is filled in the pores 187 of the first porous layer 179, thereby forming a PdAg alloy layer 189 having a thickness of 2.5 μm (which will later become a part of the hydrogen separation metal layer 183). Is formed.
<Electrolytic plating process>
As shown in FIG. 11 (b), an internal power feeding type plating device 124 (see FIG. 9) similar to that used in the fifth embodiment is used. A NaCl aqueous solution (NaCl saturated aqueous solution) having a concentration of 6.0 mol / L was introduced into the central hole 177) of the bonded body 185 as an electrolytic solution.

  Further, after inserting the feeding electrode 125 (see FIG. 9) into the NaCl electrolyte, the ceramic sintered body 185 is electroplated with an electrolytic Pd plating solution having a bath temperature of 30 ° C. in which the counter electrode 127 (see FIG. 9) is previously arranged. (Aqueous solution: concentration 10 g / L).

Then, constant current electrolytic plating was performed for 2.0 minutes at a current value of 0.50 A / dm ² , and a Pd plating metal layer 195 having a thickness of 1.5 μm was formed on the PdAg alloy layer 189 in the pores 193 of the porous layer 175. Formed.

Thereafter, heat treatment was performed at 750 ° C. in nitrogen to alloy Pd and Ag, thereby forming a hydrogen separation metal layer 183 made of a PdAg alloy having a thickness of 4.0 μm, as shown in FIG. 11C.
Through these steps, the hydrogen separator 171 was completed. The hydrogen separator 171 was attached with a metal joint 40 and the like in the same manner as in Example 5 (see FIG. 4) to form the hydrogen separator 21.

c) Next, experimental examples will be described.
Using the same experimental apparatus as in Example 5 (see FIG. 7), under the same experimental conditions (temperature, pressure), the same hydrogen-containing gas was introduced into the outer periphery of the hydrogen separator 21 of this example, A hydrogen separation test was conducted in which high-purity hydrogen was taken out from the cylinder.

As a result, hydrogen having a purity of 99.99% or more was obtained. Further, even when a test for a long time (1000 hours) was performed, the purity of hydrogen did not decrease and the durability was excellent.
d) In this example, the PdAgYSZ paste is used to form the unfired first porous layer 77 on the surface of the ceramic temporary fired body 75, and the YSZ paste is used to form the unfired first porous layer 77 on the surface. The unfired second porous layer 79 is formed, and the ceramic preliminary fired body 75 (with the unfired first porous layer 77 and the unfired second porous layer 79) is co-fired to form the first porous A ceramic sintered body 185 having a PdAg alloy layer 189 in the quality layer 179 was manufactured.

  Thereafter, Pd plating metal layer 195 is formed on the outside of PdAg alloy layer 189 by electrolytic Pd plating of an internal power feeding method, and Pd and Ag are alloyed to produce hydrogen separation metal layer 183 made of PdAg alloy. A hydrogen separator 171 was produced.

  Therefore, according to the present embodiment, the hydrogen separation metal layer 183 can be easily made dense as in the case of the fifth embodiment, so that the hydrogen separation metal layer 183 with few pinholes can be realized.

  In particular, in this embodiment, since the hydrogen separation metal layer 183 is formed by alloying after forming the Pd plating metal layer 195 by electrolytic Pd plating of the internal power feeding method, the thickness of the hydrogen separation metal layer 183 is increased and further increased. Become precise. Therefore, there is an advantage that pinholes can be greatly reduced and hydrogen embrittlement can be reduced.

Next, although the manufacturing method of the hydrogen separator of Example 7 is demonstrated, description of the content similar to the said Example 6 is abbreviate | omitted.
In addition, since the basic structure of the ceramic in the hydrogen separator of the present embodiment is the same as that of Embodiment 6, the following description will be made with reference to FIG. In addition, similar members and the like will be described using similar numbers.

  In this example, after forming an Ag metal layer using an Ag ceramic mixed paste, electrolytic Pd plating is performed to form a Pd plated metal layer, and then alloying of Pd and Ag is performed to form a hydrogen separation composed of a PdAg alloy. A metal layer is formed.

a) First, the configuration of the hydrogen separator of this example will be described.
As shown in the enlarged view of FIG. 11 (c), the hydrogen separator 201 of this example has a test tube-shaped porous support 173 and its outer surface ( A porous layer 175 covering the right side of the figure, and this porous layer 175 is composed of a first porous layer 179 and a second porous layer 181.

In particular, in this embodiment, a hydrogen separation metal layer 183 made of a PdAg alloy is formed on the entire first porous layer 179 and on the center hole 177 side (inside) in the second porous layer 181.
b) Next, the manufacturing method of the hydrogen separator 201 of a present Example is demonstrated.

  In this example, as in Example 6, the “first powder filling step”, the “second powder filling step”, the “pressurizing step”, the “temporary firing step”, the “porous layer forming step”, “ As shown in FIG. 11A, a ceramic sintered body 185 was obtained by the “firing step”.

In the “porous layer forming step”, an AgYSZ paste was prepared using a material of Ag: YSZ = 15: 85 (volume ratio).
The ceramic sintered body 185 includes a porous layer 175 composed of a first porous layer 179 and a second porous layer 181 formed so as to cover the surface of the porous support 173.

Among these, Ag is filled in the pores 187 of the first porous layer 179, thereby forming an Ag metal layer 203 having a thickness of 2 μm (which will later become a part of the hydrogen separation metal layer 183). Yes.
<Electrolytic plating process>
As shown in FIG. 11 (b), an internal power feeding type plating apparatus 124 (see FIG. 9) similar to that used in the sixth embodiment is used. A NaCl aqueous solution (NaCl saturated aqueous solution) having a concentration of 6.0 mol / L was introduced into the central hole 177) of the bonded body 185 as an electrolytic solution.

  Further, after inserting the feeding electrode 125 (see FIG. 9) into the NaCl electrolyte, the ceramic sintered body 185 is electroplated with an electrolytic Pd plating solution having a bath temperature of 30 ° C. in which the counter electrode 127 (see FIG. 9) is previously arranged. (Aqueous solution: concentration 10 g / L).

Then, constant current electrolytic plating was performed for 4.0 minutes at a current value of 0.50 A / dm ² , and a Pd-plated metal layer 195 having a thickness of 3.0 μm was formed on the Ag metal layer 203 in the pores 193 of the porous layer 175. Formed.

Thereafter, heat treatment was performed at 750 ° C. in nitrogen to alloy Pd and Ag, and as shown in FIG. 11C, a hydrogen separation metal layer 183 made of a PdAg alloy having a thickness of 5.0 μm was formed.
Through these steps, the hydrogen separator 201 was completed. Then, a metal joint 40 and the like were attached to the hydrogen separator 201 in the same manner as in Example 6 (see FIG. 4) to obtain a hydrogen separator 21.

c) Next, experimental examples will be described.
Using the same experimental apparatus as in Example 6 (see FIG. 7), under the same experimental conditions (temperature, pressure), the same hydrogen-containing gas was introduced into the outer periphery of the hydrogen separator 21 of this example, A hydrogen separation test was conducted in which high-purity hydrogen was taken out from the cylinder.

As a result, hydrogen having a purity of 99.99% or more was obtained. Further, even when a test for a long time (1000 hours) was performed, the purity of hydrogen did not decrease and the durability was excellent.
d) In this example, an unfired first porous layer 77 is formed on the surface of the ceramic pre-fired body 75 using AgYSZ paste, and the unfired first porous layer 77 is formed on the surface of YSZ paste. The unfired second porous layer 79 is formed, and the ceramic preliminary fired body 75 (with the unfired first porous layer 77 and the unfired second porous layer 79) is co-fired to form the first porous A ceramic sintered body 185 having an Ag metal layer 203 on the quality layer 179 is manufactured.

  After that, a Pd plating metal layer 195 is formed outside the Ag metal layer 203 by electrolytic Pd plating of the internal power feeding method, and Pd and Ag are alloyed to produce a hydrogen separation metal layer 183 made of a PdAg alloy. A hydrogen separator 201 was produced.

  Therefore, according to the present embodiment, the hydrogen separation metal layer 183 can be easily densified as in the sixth embodiment, so that the hydrogen separation metal layer 183 with few pinholes can be realized.

  In particular, in this embodiment, since the hydrogen separation metal layer 183 is formed by alloying after forming the Pd plating metal layer 195 by electrolytic Pd plating of the internal power feeding method, the thickness of the hydrogen separation metal layer 183 is increased and further increased. Become precise. Therefore, there is an advantage that pinholes can be greatly reduced and hydrogen embrittlement can be reduced.

In addition, this invention is not limited to the said embodiment and Example at all, and it cannot be overemphasized that it can implement with a various aspect in the range which does not deviate from this invention.
(1) For example, the electrolytic solution may be supplied to the outside of the ceramic sintered body, the electrolytic plating solution may be supplied to the inside, and the plating metal may be deposited from the inside (center hole side).

(2) The shape of the hydrogen separator is not particularly limited, and may be, for example, a flat hydrogen separator other than the bottomed cylindrical hydrogen separator.
(3) Further, as the electrolytic plating, normal electrolytic plating can be adopted in addition to the above-described internal feeding type electrolytic plating. In this case, one electrode is attached to the Pd metal layer, PdAg alloy layer, or Ag metal layer formed by the paste in the porous layer with a clip or the like so as to be conductive, and electrolytic plating is performed as usual. It can be carried out.

That is, electrolytic plating can be performed by supplying a plating solution between the metal layer (alloyed with one electrode) or alloy layer and the other electrode and applying a voltage between the two electrodes.
(4) In the hydrogen separator of each of the above embodiments (for example, a porous support), a raw material gas such as city gas is reformed (for example, steam reforming), and a hydrogen-rich reformed gas rich in hydrogen and A reforming catalyst (such as Ni) may be added.

1, 91, 101, 131, 161, 171, 201 ... Hydrogen separator 9, 103, 133, 173 ... Porous support 11, 105, 135, 175 ... Porous layer 13, 109, 139, 179 ... First Porous layer 15, 111, 141, 181 ... 2nd porous layer 19, 93, 117, 143, 183 ... Hydrogen separation metal layer (hydrogen permeable membrane)
DESCRIPTION OF SYMBOLS 20 ... Porous body 21 ... Hydrogen separator 73 ... Temporary baking porous support body 75 ... Ceramic temporary baking body 77 ... Unbaked 1st porous layer 113, 149 ... Pd metal layer 115, 195 ... Pd plating metal layer 121, 145, 185 ... Ceramic sintered body 155 ... Ag plating metal layer 163, 189 ... PdAg alloy layer 203 ... Ag metal layer

Claims (6)

In the method for producing a hydrogen separator, which produces a hydrogen separator having a hydrogen separation metal layer that allows only hydrogen to permeate inside the porous body,
A paste material is prepared by mixing Pd, which is a hydrogen separation metal, or a metal powder mainly composed of Pd and a metal that is alloyed with Pd to improve hydrogen permeability and ceramic powder. Process,
A second step of forming a surface forming layer on the support molded body by covering the surface of the porous support molded body before sintering using the paste-like material produced in the first step; ,
A third step of producing the porous body having the hydrogen separation metal layer therein by co-firing and sintering the support molded body and the surface forming layer formed in the second step;
A process for producing a hydrogen separator, comprising:   2. The hydrogen separator according to claim 1, wherein the metal constituting the hydrogen separation metal layer is supplied by electrolytic plating to the hydrogen separation metal layer of the porous body produced in the third step. Manufacturing method.   By supplying the alloy metal that improves the hydrogen permeability by alloying with the Pd by separating the hydrogen separation metal layer by the electrolytic plating, and heating at a predetermined alloying temperature, the Pd and the alloy metal The method for producing a hydrogen separator according to claim 2, wherein the alloy is alloyed. In the electrolytic plating,
An electrolyte is supplied to one side of the hydrogen separation metal layer, and electrons are supplied to the hydrogen separation metal of the hydrogen separation metal layer from the side where the electrolyte is supplied via the electrolyte. 4. The hydrogen separator according to claim 2, wherein a plating film is formed on the plating solution supply side of the hydrogen separation metal layer by supplying a plating solution to the other side of the separation metal layer. 5. Production method. In the method for producing a hydrogen separator, which produces a hydrogen separator having a hydrogen separation metal layer that allows only hydrogen to permeate inside the porous body,
A first step of preparing a paste-like material by mixing a metal powder mainly composed of a metal that is alloyed with hydrogen separation metal Pd to improve hydrogen permeability, and a ceramic powder;
A second step of forming a surface forming layer on the support molded body by covering the surface of the porous support molded body before sintering using the paste-like material produced in the first step; ,
A third step of producing the porous body having an alloy metal layer therein by co-firing and sintering the support molded body and the surface forming layer formed in the second step;
A fourth step of supplying the Pd by electrolytic plating to the porous alloy metal layer produced by the third step;
The alloying metal layer supplied with Pd in the fourth step is heated at a predetermined alloying temperature to alloy the Pd and the alloying metal to form a hydrogen separation metal layer. Process,
A process for producing a hydrogen separator, comprising: In the electrolytic plating,
An electrolyte is supplied to one side of the alloy metal layer, and electrons are supplied to the alloy metal of the alloy metal layer from the side where the electrolyte is supplied via the electrolyte. 6. The method for producing a hydrogen separator according to claim 5, wherein a plating film is formed on the plating solution supply side of the metal layer for alloy by supplying a plating solution to the other side of the metal layer for metal. .