JP2014125369A - Gas generation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology by which the deformation of a separation membrane can be suppressed.SOLUTION: A gas generation apparatus includes: a first electrode; a first room forming portion that forms a first room for housing electrolyte and first electrode; a second electrode that comprises photocatalyst; a second room forming portion that forms a second room for housing electrolyte and second electrode; a separation membrane that partitions between the first room and the second room and separates hydrogen gas and oxygen gas; and a reinforcing member that includes a support portion for supporting a part of the exposed portion which is a portion exposed to the first room or the second room of the separation membrane.

Description

  The present invention relates to a gas generator that generates at least one of hydrogen gas and oxygen gas from water using a photocatalyst.

A technique for generating hydrogen gas and oxygen gas from water using a photocatalyst (for example, an oxide semiconductor such as titanium oxide (TiO ₂ ) or tungsten oxide (WO ₃ )) is known. Moreover, in order to improve the utilization efficiency of solar energy, the technique which enlarges the contact area of water and an electrode material is proposed. For example, a technique has been proposed in which a photocatalytic material made of titanium oxide or the like is formed on the surface of a conductive substrate into an island shape, a columnar shape, or a multi-hole film shape.

JP 2003-146602 A

  In order to avoid mixing of the generated oxygen gas and hydrogen gas, it is possible to use a technique of partitioning a chamber in which oxygen gas is generated and a chamber in which hydrogen gas is generated with a separation membrane. In this case, the separation membrane can be deformed due to a pressure difference between the hydrogen gas side and the oxygen gas side, swelling due to the electrolytic solution, or the like. If the separation membrane is deformed, a problem may occur. For example, the durability of the separation membrane may be reduced unevenly.

  The main advantage of the present invention is to provide a technique capable of suppressing the deformation of the separation membrane.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following application examples.

[Application Example 1]
A gas generator that generates at least one of hydrogen gas and oxygen gas from an electrolyte containing water using a photocatalyst,
A first electrode;
A first chamber forming part for forming a first chamber for accommodating the electrolytic solution and the first electrode;
A second electrode containing a photocatalyst;
A second chamber forming part for forming a second chamber for accommodating the electrolytic solution and the second electrode;
A separation membrane for partitioning the first chamber and the second chamber and separating the hydrogen gas and the oxygen gas;
A reinforcing member including a support portion for supporting a part of an exposed portion which is a portion exposed to the first chamber or the second chamber of the separation membrane;
A gas generation device comprising:

  According to this configuration, the deformation of the separation membrane can be suppressed by the reinforcing member.

[Application Example 2]
A gas generator according to Application Example 1,
The gas generating device, wherein the support portion is fixed to the separation membrane.

  According to this configuration, the deformation of the separation membrane can be suppressed as compared with the case where the support portion is separated from the separation membrane.

[Application Example 3]
A gas generator according to Application Example 2,
The said support part is a gas production | generation apparatus fixed to the said 1st chamber side of the said separation membrane.

  According to this structure, compared with the case where the support portion is fixed to the second chamber side of the separation membrane, ions generated in the second chamber can easily enter the separation membrane, so that the gas generation efficiency is reduced. The deformation of the separation membrane can be suppressed while suppressing the above.

[Application Example 4]
The gas generator according to any one of Application Examples 1 to 3,
The support portion extends from a first position on the contour indicating the end of the exposed portion along a stretching direction when the separation membrane is bent, and is a second position on the contour different from the first position. A gas generation device including a portion that supports a portion that leads to.

  According to this structure, the support part can suppress the bending of an exposed part.

[Application Example 5]
A gas generator according to any one of Application Examples 1 to 4,
The reinforcing member is further fixed to the separation membrane, and further includes a seal portion that seals between the separation membrane and at least one of the first chamber forming portion or the second chamber forming portion. .

  According to this configuration, since the seal portion is fixed to the separation membrane, it is possible to suppress the deformation of the separation membrane and to improve the reliability against the generated gas leakage as compared with the case where the seal portion is separated from the separation membrane. It can be improved.

  In addition, this invention can be implement | achieved in various aspects, for example, can be implement | achieved in aspects, such as a gas generator, a power generation system provided with a gas generator and a fuel cell.

It is the schematic of the gas production | generation system as one Example of this invention. 2 is a cross-sectional view showing a configuration of a gas generation device 800. 2 is an exploded cross-sectional view of a gas generator 800. FIG. 2 is an exploded perspective view of a gas generation device 800. FIG. 2 is a perspective view of a membrane module 600. FIG. FIG. 3 is a schematic diagram showing the flow of protons passing through a separation membrane 330.

A. Example:
A1. Outline of gas generator:
Next, embodiments of the present invention will be described based on examples. FIG. 1 is a schematic view of a gas generation system as an embodiment of the present invention. The gas generation system 900 generates hydrogen gas and oxygen gas by electrolysis of water. The gas generation system 900 includes a gas generation device 800, a direct current power source 400, and an electrolytic solution supply device 500.

  The gas generator 800 includes a member (details will be described later) forming a first chamber 210 in which hydrogen gas is generated, a first electrode 310 accommodated in the first chamber 210, and a second chamber in which oxygen gas is generated. 220 (details will be described later), a second electrode 320 accommodated in the second chamber 220, and a separation membrane 330 that partitions the first chamber 210 and the second chamber 220.

  The DC power supply 400 applies a bias voltage between the two electrodes 310 and 320. The first electrode 310 is connected to the negative electrode of the DC power source 400, and the second electrode 320 is connected to the positive electrode of the DC power source 400.

The electrolytic solution supply apparatus 500 supplies an electrolytic solution containing water to the two chambers 210 and 220. The electrolytic solution supply apparatus 500 is connected to the first chamber 210 via the first supply path 510 and is connected to the second chamber 220 via the second supply path 520. As the electrolytic solution containing water, an aqueous solution of Na ₂ SO ₄ that allows conduction of protons (H ⁺ , also called hydrogen ions) is used. However, as the electrolytic solution, another electrolytic solution that allows conduction of protons (H ⁺ ) (for example, an aqueous solution of NaHCO ₃ ) may be employed.

The separation membrane 330 that partitions between the two chambers 210 and 220 is a membrane that restricts the passage of gas. The hydrogen gas generated by the first electrode 310 moves to the second chamber 220 and the second electrode 320. This restricts the movement of the oxygen gas generated by the first chamber 210 to the first chamber 210. Thereby, the produced | generated hydrogen gas and oxygen gas are isolate | separated, and mixing of those gas is suppressed. Further, the separation membrane 330 has proton (H ⁺ ) conductivity. In this embodiment, as such a separation membrane 330, a membrane of a fluoric resin containing a sulfonic acid group (for example, Nafion (trademark of DuPont)) is used. Such a fluororesin film is also called an electrolyte film.

The first electrode 310 is configured using a conductive material (here, stainless steel). The second electrode 320 is configured using a conductive material including tungsten oxide (WO ₃ ) as a photocatalyst that promotes electrolysis of water using light. When the second electrode 320 is irradiated with light such as sunlight, oxygen (O ₂ ) and protons (H ⁺ ) are generated from water (H ₂ O) by the action of the photocatalyst, and electrons (E ⁻ ) is generated in the second electrode 320.

The oxygen gas is discharged out of the second chamber 220 through the second gas flow path 420 connected to the second chamber 220. The discharged oxygen gas is stored in an oxygen tank (not shown). However, the oxygen gas may be released to a predetermined space (for example, in the atmosphere) without storing. The electrons (e ⁻ ) generated in the second electrode 320 move to the DC power source 400, and the electrons (e ⁻ ) are supplied from the DC power source 400 to the first electrode 310. Protons (H ⁺ ) pass through the separation membrane 330 and move to the first chamber 210.

Protons (H ⁺ ) moved to the first chamber 210 are combined with electrons (e ⁻ ) at the first electrode 310 to generate hydrogen gas (H ₂ ). The generated hydrogen gas (H ₂ ) is discharged out of the first chamber 210 through the first gas flow path 410 connected to the first chamber 210. The discharged hydrogen gas (H ₂ ) is stored, for example, in a hydrogen tank (not shown). Further, hydrogen gas may be supplied to a fuel cell (not shown).

A2. Details of gas generator:
2 is a cross-sectional view showing a configuration of the gas generation device 800, FIG. 3 is an exploded cross-sectional view of the gas generation device 800, and FIG. 4 is an exploded perspective view of the gas generation device 800. In the figure, three directions Dx, Dy, and Dz orthogonal to each other are shown. 2 and 3 are cross-sectional views orthogonal to the second direction Dy, and are AA cross-sections shown in FIG. Hereinafter, the first direction Dx is also referred to as “+ Dx direction”, and the opposite direction of the first direction Dx is also referred to as “−Dx direction”. The + Dx direction side is also simply referred to as “+ Dx side”, and the −Dx direction side is also simply referred to as “−Dx side”. Similarly, the second direction Dy is also referred to as “+ Dy direction”, and the direction opposite to the second direction Dy is “−Dy direction”, the + Dy direction side is “+ Dy side”, and the −Dy direction side is “−Dy direction”. Called “side” respectively. The third direction Dz is also referred to as “+ Dz direction”, and the direction opposite to the third direction Dz is “−Dz direction”, the + Dz direction side is “+ Dz side”, and the −Dz direction side is “−Dz side”. ", Respectively.

A2-1. Room 1:
As shown in FIG. 2, the first chamber 210 is a space formed by the container 110 and the separation membrane 330. Hereinafter, the container 110 is also referred to as a “first chamber forming unit 110”. The container 110 is a bottomed container having an opening 111 facing the -Dz direction and a storage chamber 112 which is a recess communicating with the opening 111. As shown in FIG. 4, the shape of the opening 111 is approximately the same as a rectangular shape constituted by a line parallel to the first direction Dx and a line parallel to the second direction Dy. The shape of the storage chamber 112 is approximately the same as a rectangular parallelepiped having the opening 111 as one surface.

  As shown in FIGS. 2 and 3, the container 110 has a through hole 113 formed on the + Dx side of the storage chamber 112 and extending along the + Dx direction. The through hole 113 communicates the storage chamber 112 with the outside of the container 110. Hereinafter, the direction (here, the first direction Dx) in which the through hole 113 extends from the storage chamber 112 to the outside is also referred to as “insertion direction Dx”. Further, the container 110 has a recess 114 formed on the side opposite to the through hole 113 in the accommodation chamber 112 (that is, on the −Dx side). As shown in FIG. 4, the recess 114 extends from the −Dy side end of the storage chamber 112 to the + Dy side end. The container 110 is formed as a single member using an insulating material (for example, resin).

  As shown in FIGS. 3 and 4, the first electrode 310 has a mesh-shaped portion 311 (referred to as “mesh portion 311”) in which a large number of holes are formed, and an end on the −Dx side of the mesh portion 311. The first bus bar 312 is fixed, the second bus bar 313 is fixed to the end of the mesh portion 311 on the + Dx side, and the terminal 314 is fixed to the second bus bar 313 and protrudes in the + Dx direction. . As shown in FIG. 4, the mesh portion 311 is a substantially rectangular plate having a line-shaped end parallel to the first direction Dx and a line-shaped end parallel to the second direction Dy. They are arranged so as to be orthogonal to the direction Dz. When observed in the third direction Dz, the mesh portion 311 extends over substantially the entire interior of the storage chamber 112. The first bus bar 312 and the second bus bar 313 respectively extend from the −Dy side end of the mesh portion 311 to the + Dy side end. All the parts 311, 312, 313, and 314 of the first electrode 310 are formed using stainless steel. For example, welding can be used as a method of fixing the portions 311, 312, 313, and 314 to each other.

  As shown in FIG. 2, the terminal 314 of the first electrode 310 is inserted into the through hole 113 of the container 110 from the inside of the accommodation chamber 112 (that is, inside the container 110). The terminal 314 and the through hole 113 are sealed with an O-ring 315. The O-ring 315 is formed using an elastic material (for example, rubber). The through hole 113 supports the first electrode 310 by inserting the terminal 314 into the through hole 113.

  As shown in FIG. 2, the first bus bar 312 of the first electrode 310 is inserted into the recess 114 of the container 110. Accordingly, the recess 114 supports the first bus bar 312, that is, the first electrode 310.

  A length L1x illustrated in FIG. 3 indicates a length along the insertion direction Dx of the first electrode 310 in a state of being accommodated in the accommodation chamber 112. The length L1x is longer than the length L2x along the insertion direction Dx of the opening 111. As described above, the first electrode 310 is longer than the opening 111. On the other hand, the mesh portion 311 of the first electrode 310 is elastically deformable. Therefore, by bending the mesh portion 311, the terminal 314 can be inserted into the through hole 113, and the first bus bar 312 can be inserted into the recess 114.

  As shown in FIGS. 2 and 4, the membrane module 600 is disposed on the −Dz side of the container 110. FIG. 5 is a perspective view of the membrane module 600. Between FIG. 5 (A) and FIG. 5 (B), the directions to be observed are opposite to each other. The membrane module 600 includes a separation membrane 330 and a reinforcing member 390. The reinforcing member 390 includes a first seal portion 391 and a support portion 395 shown in FIG. 5 (A), and a second seal portion 392 shown in FIG. 5 (B).

  As shown in FIG. 5A, the separation membrane 330 is a flat membrane. The first seal portion 391 is a loop-shaped portion provided over the entire periphery at the edge portion of the + Dz side surface of the separation membrane 330. The support portion 395 is a lattice-like portion provided inside the first seal portion 391. As shown in FIG. 5B, the second seal portion 392 is a loop-like portion provided over the entire periphery of the edge portion of the surface of the separation membrane 330 on the −Dz side. Each of the portions 391, 392, and 395 of the reinforcing member 390 is made of resin. Details of the membrane module 600 will be described later.

  As shown in FIGS. 2 and 4, the separation membrane 330 covers the entire opening 111 of the container 110 to block the opening 111. The first seal portion 391 is in close contact with the end surface on the −Dz side of the container 110 and the separation membrane 330, and forms the container 110 (that is, the first chamber 210 that forms the first chamber 210) over the entire circumference surrounding the opening 111. Part 110) and the separation membrane 330 are sealed.

A2-2. Room 2:
As shown in FIG. 2, the second chamber 220 is a space formed by the second chamber forming part 140, the separation membrane 330, and the glass plate 324. The second chamber forming part 140 includes a first wall member 120 and a second wall member 130 disposed on the −Dz side of the first wall member 120.

  As shown in FIG. 4, the first wall member 120 is a loop-shaped member having a through hole 122 extending along the third direction Dz. As shown in FIGS. 3 and 4, the first wall member 120 includes a first portion 120a (+ Dz side portion) and a second portion 120b (−Dz side portion) having different through-holes 122 in size. Divided into two parts. The through hole 122 formed by the second portion 120b is larger than the through hole 122 formed by the first portion 120a. When observed in the third direction Dz, the inner peripheral surface of the first portion 120 a substantially overlaps the inner peripheral surface of the opening 111 of the container 110. The first wall member 120 is formed using an insulating material (for example, resin).

  As shown in FIG. 4, the second wall member 130 is a loop-shaped member having a through hole 132 extending along the third direction Dz. As shown in FIGS. 3 and 4, when observed in the third direction Dz, the shape of the through hole 132 is substantially rectangular, and the inner peripheral surface of the through hole 132 is the first wall member 120. It substantially overlaps with the inner peripheral surface of the one portion 120a. The second wall member 130 is formed using an insulating material (for example, resin).

  As shown in FIGS. 3 and 4, the second electrode 320 includes a glass plate 324, a transparent conductive layer 323 formed on the entire surface of the glass plate 324 on the + Dz side, and a + Dz side of the transparent conductive layer 323. The photocatalyst layer 322 formed in the part inside the edge on the surface, and the metal fitting 325 which contacts the edge part on the surface on the + Dz side of the transparent conductive layer 323 over the entire circumference. The metal fitting 325 is formed in a loop shape so as not to cover the photocatalyst layer 322. As shown in FIG. 2, the second electrode 320 is fitted into the second portion 120 b of the first wall member 120, and is sandwiched between the first portion 120 a of the first wall member 120 and the second wall member 130. The through hole 132 of the second wall member 130 is closed by the glass plate 324. A space on the + Dz side of the glass plate 324 of the through hole 122 of the first wall member 120 corresponds to the second chamber 220.

  As shown in FIGS. 3 and 4, a loop-shaped seal member 393 is disposed on the inner peripheral side of the metal fitting 325. The seal member 393 is sandwiched between the transparent conductive layer 323 and the first wall member 120 (more specifically, the first portion 120a), and between the second electrode 320 and the first wall member 120, The entire circumference of the through hole 122 is sealed. The seal member 393 is formed using an elastic material (for example, rubber).

  As shown in FIG. 4, when observed in the third direction Dz, the contour shapes of the transparent conductive layer 323, the glass plate 324, and the metal fitting 325 are substantially rectangular. Further, as shown in FIGS. 2 and 4, the contours of the members 323, 324, and 325 are slightly inside the inner peripheral surface of the second portion 120 b of the first wall member 120 over the entire circumference. It is located and is located outside the inner peripheral surface of the first portion 120a of the first wall member 120 over the entire circumference.

The photocatalyst layer 322 is formed by forming tungsten oxide (WO ₃ ) into a film shape. The transparent conductive layer 323 is formed by forming a film of FTO (fluorine-doped tin oxide) as a conductive material, and can transmit light used by the photocatalytic layer 322. The glass plate 324 can also transmit light used by the photocatalytic layer 322. As shown in FIG. 2, light (for example, sunlight) enters from the through hole 132 of the second wall member 130, passes through the glass plate 324 and the transparent conductive layer 323, and reaches the photocatalyst layer 322. The photocatalyst layer 322 that has received light promotes electrolysis of water. In the photocatalyst layer 322, electrons (e ⁻ ) are generated. The generated electrons (e ⁻ ) are collected in the metal fitting 325 through the transparent conductive layer 323.

The metal fitting 325 is formed using a conductive material (for example, stainless steel). Since the metal fitting 325 is in contact with the edge of the transparent conductive layer 323 over the entire circumference, electrons (e ⁻ ) can be efficiently collected from the transparent conductive layer 323. The metal fitting 325 is configured to have elasticity in order to reduce the contact resistance between the metal fitting 325 and the transparent conductive layer 323. In this embodiment, the metal fitting 325 is formed by folding a net of a conductive material. The thickness of the metal fitting 325 in the third direction Dz is set so that a sufficient contact area with the transparent conductive layer 323 can be realized in consideration of the crushing rate of the seal member 393. A terminal (not shown) is connected to the metal fitting 325 from the outside of the gas generator 800. As illustrated in FIG. 4, a notch 124 for inserting a terminal (not shown) is formed on the + Dx side of the second portion 120 b of the first wall member 120. Further, a notch 134 for inserting a terminal (not shown) is also formed on the + Dx side of the second wall member 130.

  As shown in FIGS. 2 and 4, the membrane module 600 is disposed on the + Dz side of the second chamber forming portion 140 (specifically, the first wall member 120). The separation membrane 330 covers the entire through hole 122 of the first wall member 120 to close the through hole 122. The second seal portion 392 is in close contact with the first wall member 120 and the separation membrane 330, and the first wall member 120 (that is, the second chamber forming the second chamber 220) over the entire circumference surrounding the through hole 122. The gap between the forming unit 140) and the separation membrane 330 is sealed.

A2-3. Other parts:
As shown in FIG. 4, the plurality of members of the gas generation device 800 are fixed by a plurality of bolts 380. For the plurality of bolts 380, the container 110 has a plurality of screw holes 119, the membrane module 600 has a plurality of screw holes 609, and the first wall member 120 has a plurality of screw holes 129. The second wall member 130 has a plurality of screw holes 139. A female screw is formed in the screw hole 119 of the container 110. The bolt 380 passes through the screw holes 139, 129, and 609 from the −Dz side, and is screwed into the screw hole 119 of the container 110. The plurality of screw holes 119, 129, 139, and 609 are disposed so as to surround the storage chamber 112 and the through holes 122 and 132 (that is, the first chamber 210 and the second chamber 220).

  Although not shown, the container 110 is provided with a connection port for connecting the first gas flow path 410 (FIG. 1) and a connection port for connecting the first supply path 510. Yes. Although not shown, the first wall member 120 is provided with a connection port for connecting the second gas flow path 420 and a connection port for connecting the second supply path 520. .

A3. Details of the membrane module 600:
First, the seal portions 391 and 392 will be described. As described above, the first seal portion 391 (FIG. 5A) is fixed to the edge portion of the + Dz side surface of the separation membrane 330 over the entire circumference. Specifically, the entire first seal portion 391 is integrated with the separation membrane 330 and joined to the separation membrane 330. Therefore, the airtightness of the first chamber 210 (FIG. 2) can be easily improved. Further, deformation (for example, bending and bending) of the separation membrane 330 can be suppressed. Therefore, the membrane module 600 (that is, the separation membrane 330) can be easily handled when the gas generator 800 is manufactured. Similarly, the second seal portion 392 (FIG. 5B) is fixed to the edge portion of the + Dz side surface of the separation membrane 330 over the entire circumference. Specifically, the entire second seal portion 392 is integrated with the separation membrane 330 and joined to the separation membrane 330. Therefore, the airtightness of the second chamber 220 (FIG. 2) can be easily improved, and further, the deformation of the separation membrane 330 can be suppressed. In addition, since the seal portions are fixed on both sides of the separation membrane 330, deformation of the separation membrane 330 can be appropriately suppressed.

Next, the support part 395 will be described. In FIG. 5A, the exposed portion 330e of the separation membrane 330 is indicated by a broken line. The broken line shown in the figure indicates an outline indicating the end of the exposed portion 330e when observed in a direction perpendicular to the separation membrane 330 (for example, the −Dz direction). The exposed portion 330e is a portion of the first chamber 210 and the second chamber 220 that is exposed to the chamber in which the support portion 395 is disposed. The support part 395 supports a part of the exposed part 330e by contacting a part of the exposed part 330e. The remaining portion of the exposed portion 330e is not covered with the support portion 395. Therefore, the support portion 395 can suppress deformation (for example, bending) of the separation membrane 330 without inhibiting protons (H ⁺ ) from passing through the separation membrane 330.

  In addition, the support portion 395 includes a first line portion 395a. The first line portion 395a is a portion from the first position P1 on the contour indicating the end of the exposed portion 330e to the second position P2 on the contour different from the first position P1 through the inside of the contour. I support it. Thus, since the 1st line part 395a supports the part which crosses the inner side of the outline of the exposed part 330e, the bending of the exposed part 330e can be suppressed. As shown in the figure, since the support portion 395 includes a plurality of such line portions that support different positions, the deflection of the exposed portion 330e can be appropriately suppressed.

  Further, the support portions 395 are arranged approximately evenly over the entire separation membrane 330. Therefore, the support portion 395 can suppress deformation (for example, bending) over the entire separation membrane 330.

  In the present embodiment, the support portion 395 is fixed to the separation membrane 330. Therefore, the support part 395 can suppress wrinkles from occurring in the separation membrane 330. Further, the support portion 395 can suppress the separation membrane 330 from being bent. Therefore, the membrane module 600 (that is, the separation membrane 330) can be easily handled when the gas generator 800 is manufactured.

If the separation membrane 330 is deformed (for example, bent or wrinkled), the flow of protons (H ⁺ ) can be uneven on the separation membrane 330. Therefore, the load applied to the separation membrane 330 may be uneven. When a material that conducts hydrated protons (for example, a resin containing a sulfonic acid group) is employed as the material of the separation membrane 330, the separation membrane 330 swells due to the conduction of protons. When the proton flow is uneven on the separation membrane 330, swelling also occurs unevenly. As described above, when the flow and swelling of protons occur unevenly, the degradation of the separation membrane 330 may progress unevenly. In addition, gas generation may become unstable. Further, due to the deformation of the separation membrane 330, the stress applied to the separation membrane 330 can also be uneven. As a result, the durability of the separation membrane 330 may be reduced unevenly. This embodiment can suppress such a problem.

In the present embodiment, the support portion 395 is fixed to the first chamber 210 side of the separation membrane 330. The reason for this will be described below. FIG. 6 is a schematic diagram showing the flow of protons passing through the separation membrane 330. In the drawing, a cross-sectional view of the separation membrane 330 is shown. The cross-sectional view includes a portion supported by the support portion 395. Protons (H ⁺ ) reach the surface of the separation membrane 330 on the second chamber 220 side (referred to as “upstream surface 330 u”). The protons that have reached the upstream surface 330u move inside the separation membrane 330 and reach the surface of the separation membrane 330 on the first chamber 210 side (referred to as the “downstream surface 330d”). Then, protons move from the downstream surface 330d to the first chamber 210. As shown in the drawing, a part of the downstream surface 330 d is covered with a support portion 395. Protons move from the portion not covered by the support portion 395 to the first chamber 210.

  Within the separation membrane 330, protons can easily move. Therefore, even when a part of the downstream surface 330d is covered by the support portion 395, protons that have reached the upstream surface 330u can easily move to the first chamber 210. That is, even if the support portion 395 is fixed to the downstream surface 330d, the influence of the proton flow from the second chamber 220 to the first chamber 210 is small.

  Suppose that the support portion 395 is fixed to the upstream surface 330u. In this case, the area of the upstream surface 330u through which protons from the second chamber 220 can enter decreases. As a result, the protons are suppressed from reaching the separation membrane 330, so that the proton flow from the second chamber 220 to the first chamber 210 is suppressed.

  As described above, in this embodiment, in consideration of the flow of protons from the second chamber 220 to the first chamber 210, the support portion 395 is fixed to the first chamber 210 side of the separation membrane 330.

  As described above, the support portion 395 and the seal portions 391 and 392 are formed using an ultraviolet curable resin. Specifically, first, the separation membrane 330 is prepared. Next, an uncured support portion 395 and an uncured first seal portion 391 are formed on the + Dz side surface of the separation membrane 330 by screen printing using an uncured resin material. Next, the support part 395 and the first seal part 391 are cured by irradiating with ultraviolet rays. After curing, the portion of the membrane module 600 that protrudes outside the predetermined contour is cut. Similarly, on the −Dz side of the separation membrane 330, an uncured second seal portion 392 is formed by screen printing, and the second seal portion 392 is cured by irradiating ultraviolet rays, and the protruding portion is cut. The cutting of the portion that protrudes from the outline of the membrane module 600 may be performed after the curing of both sides is completed. Further, after the resin is cured, a screw hole 609 is formed.

  In this manner, the uncured support portion 395 and the seal portions 391 and 392 using an ultraviolet curable resin are formed on the separation membrane 330, and these portions 391, 392, and 395 are cured on the separation membrane 330. Then, the adhesion between the separation membrane 330 and the cured portions 391, 392, 395 can be improved. In addition, since the resin can be fixed to the separation membrane 330 without using heat, it is possible to prevent the separation membrane 330 from being altered by heat.

  In this embodiment, the support portion 395 is continuous with the first seal portion 391. Therefore, the deformation of the support portion 395 can be appropriately suppressed as compared with the case where the support portion 395 is separated from the first seal portion 391.

  Further, as shown in FIG. 5A, a plurality of screw holes 609 through which a plurality of bolts 380 pass are provided in the edge portion of the membrane module 600. The plurality of screw holes 609 (that is, the bolts 380) are arranged so as to surround the exposed portion 330e. Each screw hole 609 passes through the first seal portion 391, the separation membrane 330, and the second seal portion 392. As shown in FIG. 4, the bolt 380 includes the first chamber forming portion 110 and the second chamber forming portion in a state where the membrane module 600 is disposed between the first chamber forming portion 110 and the second chamber forming portion 140. 140 are fixed in a direction facing each other. The first seal portion 391 and the second seal portion 392 receive a tightening force by the bolt 380 while being sandwiched between the first chamber forming portion 110 and the second chamber forming portion 140. Accordingly, displacement and deformation of the first seal portion 391 and the second seal portion 392 are suppressed by the tightening force by the bolt 380. As a result, deformation of the separation membrane 330 to which the first seal portion 391 and the second seal portion 392 are fixed is also suppressed. In addition, since deformation of the support portion 395 continuous with the first seal portion 391 is also suppressed, deformation of the separation membrane 330 is further suppressed.

  As shown in FIG. 5A, the support portion 395 includes a line portion formed along a line connecting the vicinity of the screw hole 609 and the vicinity of the other screw hole 609. For example, the first line portion 395a is formed along a line connecting the vicinity range Ca of the first screw hole 609a and the vicinity range Cb of the second screw hole 609b. The position near the screw hole is more strongly subjected to the tightening force by the bolt 380 than the position far from the screw hole. Therefore, both ends of the first line portion 395a are firmly received by the force tightened by the bolt 380. As a result, the deformation of the first line portion 395a can be suppressed as compared with the case where at least one of both ends of the first line portion 395a is separated from the vicinity of the screw hole 609. That is, the deformation of the separation membrane 330 supported by the first line portion 395a can be suppressed. The same applies to other portions (other line portions) of the support portion 395.

  In addition, the vicinity range of the screw hole 609 can be determined as follows, for example. The first screw hole 609a will be described as an example. First, a screw hole far from the first screw hole 609a is specified out of the two screw holes 609c and 609d adjacent to the first screw hole 609a. In the embodiment of FIG. 5, the first distance Ld between the first screw hole 609a and the third screw hole 609c is greater than the second distance Le between the first screw hole 609a and the fourth screw hole 609d. long. Therefore, the third screw hole 609c is specified. As the vicinity range of the first screw hole 609a, a range Ca that is ¼ or less of the distance Ld between the first screw hole 609a and the specified adjacent screw hole 609c can be employed. The vicinity range determined in this way is the half of the area between the first screw hole 609a and the adjacent third screw hole 609c, and one of the two screw holes 609a and 609c. This means that it is treated as a neighborhood.

  Further, as described above, the seal portions 391 and 392 are used for improving the airtightness in addition to suppressing the deformation of the separation membrane 330. In order to improve hermeticity, it is preferable that the seal portions 391 and 392 are soft. On the other hand, the support portion 395 is exclusively used for suppressing deformation of the separation membrane 330. Therefore, it is preferable that the support part 395 is hard. As described above, in this embodiment, the resin material is adjusted so that the hardness of the cured seal portions 391 and 392 is smaller than the hardness of the cured support portion 395. Small hardness indicates softness. As the ultraviolet curable resin, those having various hardness from a hard one to a soft one are widespread. When screen printing is performed, a material that achieves a relatively small hardness is used to form the seal portions 391 and 392, and a material that realizes a relatively large hardness is used to form the support portion 395. It is done. In addition, as hardness, the Shore hardness standardized as JISK6253 is employable.

  Further, in this embodiment, a reinforcing member 390 that is more difficult to bend than the separation membrane 330 is used to suppress the deflection of the separation membrane 330. Here, the ease of bending can be compared using the amount of bending described below. That is, a gas generating device in which the reinforcing member 390 is omitted is prepared, and the gas generating device is arranged so that the + Dz direction (FIG. 2) is directed vertically downward. Then, a weight is placed on the central portion (−Dz side) of the separation membrane 330. The difference in height between the lowermost position of the separation membrane 330 before placing the weight and the lowermost position of the separation membrane 330 after placing the weight is adopted as the amount of deflection of the separation membrane 330. The amount of bending of the reinforcing member 390 is also measured in the same manner using a gas generating device in which the separation membrane 330 is omitted and the same weight. If the amount of bending of the reinforcing member 390 is smaller than the amount of bending of the separation membrane 330, it can be said that the reinforcing member 390 is less likely to be bent than the separation membrane 330.

  When measuring the lowest position, some members (for example, the 2nd electrode 320) of gas generating device 800 may be removed beforehand. However, the measurement of the lowest position is performed in a state where the tightening force between the first chamber forming unit 110 and the second chamber forming unit 140 is maintained at the design value of the gas generating device 800 (for example, a bolt 380). Is tightened at the torque design value).

  Note that various methods can be employed as a method of forming the reinforcing member 390 that is less likely to bend than the separation membrane 330. For example, the reinforcing member 390 (particularly, the support portion 395) may be formed using a hard material. Further, the support portion 395 may be thickened.

  Moreover, as described above, the separation membrane 330 may swell by absorbing water. When the separation membrane 330 swells, it easily deforms. Similarly, since the support portion 395 is also used in the electrolytic solution, it may swell by absorbing water. When the support part 395 is easily deformed by swelling, the separation membrane 330 is also easily deformed. Therefore, in this embodiment, the water absorption rate of the support portion 395 is smaller than the water absorption rate of the separation membrane 330 in order to suppress the swelling of the support portion 395. As the ultraviolet curable resin, various resins are widely used from those having a large water absorption rate to those having a small water absorption rate. When screen printing is performed, a material that realizes a water absorption rate smaller than the water absorption rate of the separation membrane 330 is used to form the support portion 395. In addition, as a water absorption, the water absorption standardized as JIS K7209 is employable.

B. Variations:
(1) As the configuration of the support portion 395 (FIG. 5A), any configuration that supports a part of the exposed portion 330e of the separation membrane 330 can be employed. For example, a member configured in a net shape may be employed, or a plate in which a large number of through holes are formed may be employed. Further, the support portion 395 may be disposed regardless of the position of the screw hole 609 of the separation membrane 330. Here, the support portion extends from the first position on the contour indicating the end of the exposed portion 330e along the expansion / contraction direction when the separation membrane 330 is bent, and the second position on the contour different from the first position. It is preferable that the part which goes to includes a supporting part. For example, when the separation membrane 330 is bent, the vicinity of the contour line of the exposed portion 330e of the separation membrane 330 may expand and contract in a direction perpendicular to the contour line. In such a case, if a support part including a portion extending from a position on the contour line along a direction orthogonal to the contour line is employed, the bending of the separation membrane 330 can be appropriately suppressed. For example, in the embodiment shown in FIG. 5A, the contour shape of the exposed portion 330e is a substantially rectangular shape formed by two sides parallel to the first direction Dx and two sides parallel to the second direction Dy. . The first line portion 395a extends from the first position P1 along a direction (−Dx direction) orthogonal to the contour line at the first position P1, and reaches the second position P2. It is also possible to adopt a circular shape as the shape of the exposed portion. In this case, the direction orthogonal to the contour line at the first position on the contour line of the exposed portion is the direction toward the center of the circular shape. Therefore, it is preferable to employ a support portion that supports a portion from the first position on the contour line through the circular center to the second position on the opposite side. In any case, in order to suppress the bending of the separation membrane 330, the part from the first position to the second position is preferably a linear part.

  Note that the first position and the second position on the contour through which the support portion passes may be determined regardless of the direction orthogonal to the contour line. In addition, as a configuration of the support portion, various configurations including a portion from the first position on the contour of the exposed portion to the second position on the contour different from the first position through the inside of the contour can be adopted. It is. Various shapes (for example, a linear shape and a curved shape) can be adopted as the shape of the portion from the first position to the second position. In any case, it is preferable to configure the support portion 395 so as to support the entire separation membrane 330 (particularly, the exposed portion 330e) approximately equally.

  Further, the support portion 395 may be separated from the separation membrane 330 without being fixed to the separation membrane 330. Further, the support part 395 may be separated from the first seal part 391. In any case, it is preferable that the support part 395 includes a portion sandwiched between the first chamber forming part 110 and the second chamber forming part 140. For example, in the embodiment of FIGS. 2 and 5A, the end portion of the support portion 395 (the portion outside the exposed portion 330e) is sandwiched between the first chamber forming portion 110 and the second chamber forming portion 140. It is. By doing so, the deformation of the support portion 395 is suppressed, so that the deformation of the separation membrane 330 can be suppressed.

  In addition, a support part 395 may be provided on the second chamber 220 side of the separation membrane 330. When hydrogen gas and oxygen gas are generated by electrolysis of water, the amount of hydrogen gas produced (also referred to as “number of moles”) is twice the amount of oxygen gas produced. Therefore, the pressure in the first chamber 210 may be higher than the pressure in the second chamber 220. In this case, the separation membrane 330 bends toward the second chamber 220 side. Then, if the support part 395 is provided in the 2nd chamber 220 side, the bending of the separation membrane 330 can be suppressed appropriately. In this case, it is preferable to reduce the area of the portion hidden by the support portion 395 in the separation membrane 330 in consideration of the flow of protons. Further, support portions may be provided on both sides of the separation membrane 330 on the first chamber 210 side and the second chamber 220 side.

  Further, the material of the support portion is not limited to the ultraviolet curable resin, and various resins such as rubber can be employed. Moreover, not only resin but various insulating materials, such as glass, are employable. Moreover, you may employ | adopt not only an insulating material but various materials, such as a metal and carbon. Further, the water absorption rate of the support portion may be equal to or higher than the water absorption rate of the separation membrane 330. In general, various materials having good corrosion resistance (for example, acid resistance and alkali resistance) against the electrolytic solution can be adopted as the material for the support portion.

(2) The structure of the seal part (for example, the first seal part 391 (FIG. 5A) and the second seal part 392 (FIG. 5B)) is the first chamber 210 side of the separation membrane 330 and the first seal part 392. Various loop-shaped configurations that seal at least one side of the two chambers 220 can be employed. For example, a seal portion may be formed between the screw hole 609 (FIG. 5A) of the separation membrane 330 and the exposed portion 330e.

  The material of the seal portion is not limited to the ultraviolet curable resin, and various resins can be used. Moreover, not only resin but various elastic materials, such as rubber | gum, are employable. Moreover, you may form a seal | sticker part with the same material as a support part. Further, the hardness of the seal portion may be equal to or higher than the hardness of the support portion. In general, various materials having good corrosion resistance (for example, acid resistance and alkali resistance) against the electrolytic solution can be employed as the material for the seal portion.

(3) As the configuration of the reinforcing member 390 (FIGS. 5A and 5B), various configurations including a support portion that supports a part of the exposed portion 330e of the separation membrane 330 can be employed. For example, the second seal portion 392 on the second chamber 220 side may be omitted. That is, the seal portion may be formed only on the first chamber 210 side of the separation membrane 330. In this case, the separation membrane 330 and the second chamber forming portion 140 may be sealed with an O-ring (not shown) separate from the reinforcing member 390. Instead, the first seal portion 391 on the first chamber 210 side may be omitted. That is, the seal portion may be formed only on the second chamber 220 side of the separation membrane 330. In this case, what is necessary is just to seal between the separation membrane 330 and the 1st chamber formation part 110 with another O-ring (not shown) from the reinforcement member 390. Further, the respective seal portions on the first chamber 210 side and the second chamber 220 side may be omitted. Further, the reinforcing member 390 may be more flexible than the separation membrane 330.

(4) In the embodiment of FIG. 4, the number of bolts 380 is “8”, but any number N (N is an integer of 2 or more) can be adopted as the number of bolts. In addition, the fixing member that fastens and fixes the first wall member 120 and the second chamber forming portion 140 in a direction facing each other is not limited to the bolt 380, and various members can be employed. For example, rivets may be adopted. Further, the method for fixing the plurality of members of the gas generating device 800 is not limited to the method using such a fixing member, and various methods can be employed. For example, the entire gas generation device 800 may be tied with a belt.

Moreover, as a structure of a gas production | generation apparatus, the following structures are employable. That is, the gas generating device tightens the first chamber forming portion and the second chamber forming portion in a direction facing each other in a state where the separation membrane is disposed between the first chamber forming portion and the second chamber forming portion. And N fixing members (N is an integer of 2 or more). The N fixing members are arranged so as to surround the periphery of the exposed portion of the separation membrane. The separation membrane has N holes through which the fixing member passes. The support portion includes a line portion that is a portion formed along a line connecting the vicinity of the hole and the vicinity of the other hole.
According to this configuration, since the deformation of the line portion of the support portion is limited by the tightening force by the fixing member that penetrates the hole, the deformation of the separation membrane can be suppressed.

(5) The photocatalyst used for the electrode that generates oxygen is not limited to tungsten oxide (WO ₃ ), and various materials that promote electrolysis of water using light can be employed. The material of the photocatalyst is not necessarily limited to WO ₃ , but TiO ₂ (titanium dioxide), SrTiO ₃ (strontium titanate), BaTiO ₃ (barium titanate), ZrO (zinc oxide), SnO _2. Any highly functional oxide semiconductor photocatalyst such as (tin dioxide (tin)) or CdS (cadmium sulfide) can be selected.

(6) As the separation membrane 330, various membranes that restrict (preferably prevent) the passage of gas (specifically, hydrogen gas and oxygen gas) can be used. Here, in order to efficiently generate hydrogen gas, a membrane having proton (H ⁺ ) conductivity is employed. For example, a filter provided with a large number of pores that allow protons (H ⁺ ) to pass therethrough can be employed. In addition to the fluorine resin film described above, for example, a hydrocarbon resin film can be used as the proton (H ⁺ ) conductivity film.

(7) As each structure of the 1st chamber formation part 110 and the 2nd chamber formation part 140, various structures different from the structure of an Example are employable. For example, as the shape of the first chamber 210, any shape such as a columnar shape can be adopted. Further, the recess 114 may be omitted. Moreover, the 1st chamber formation part 110 may be divided | segmented into the some member. Similarly, various shapes can be adopted as the shape of the second chamber 220.

(8) As each structure of the 1st electrode 310 and the 2nd electrode 320, various structures different from the structure of an Example are employable. For example, the length L1x (FIG. 3) of the first electrode 310 may be shorter than the length L2x of the opening 111. Further, the second electrode may include a metal member and a photocatalyst fixed directly to the surface of the metal member.

  As mentioned above, although this invention was demonstrated based on the Example and the modification, Embodiment mentioned above is for making an understanding of this invention easy, and does not limit this invention. The present invention can be changed and improved without departing from the spirit and scope of the claims, and equivalents thereof are included in the present invention.

110 ... container (first chamber forming part), 111 ... opening, 112 ... receiving chamber, 113 ... through hole, 114 ... recess, 119 ... screw hole, 120 ... First wall member, 120a ... first part, 120b ... second part, 122 ... through hole, 124 ... notch, 130 ... second wall member, 132 ... through hole, 134 ... notch, 139 ... screw hole, 140 ... second chamber forming part, 210 ... first chamber, 220 ... second chamber, 310 ... first electrode, 311 ... Mesh portion, 312 ... first bus bar, 313 ... second bus bar, 314 ... terminal, 315 ... O-ring, 320 ... second electrode, 322 ... photocatalytic layer, 323. .. Transparent conductive layer, 324 ... Glass plate, 325 ... Metal fitting, 330 ... Separation membrane, 330d ... Downstream surface, 330e ... Exposed portion, 330u ... Upstream surface, 380 ... .Bolt, 390 ... reinforcing member, 391 ... first seal part, 392 ... second seal 393 ... Sealing member, 395 ... Supporting part, 395a ... First line portion, 400 ... DC power supply, 410 ... First gas flow path, 420 ... Second gas flow path , 500 ... Electrolyte supply device, 510 ... First supply path, 520 ... Second supply path, 600 ... Membrane module, 609 ... Screw hole, 609a ... First screw hole 609b ... second screw hole, 609c ... third screw hole, 609d ... fourth screw hole, 800 ... gas generating device, 900 ... gas generating system

Claims (5)

A gas generator that generates at least one of hydrogen gas and oxygen gas from an electrolyte containing water using a photocatalyst,
A first electrode;
A first chamber forming part for forming a first chamber for accommodating the electrolytic solution and the first electrode;
A second electrode containing a photocatalyst;
A second chamber forming part for forming a second chamber for accommodating the electrolytic solution and the second electrode;
A separation membrane for partitioning the first chamber and the second chamber and separating the hydrogen gas and the oxygen gas;
A reinforcing member including a support portion for supporting a part of an exposed portion which is a portion exposed to the first chamber or the second chamber of the separation membrane;
A gas generation device comprising: The gas generator according to claim 1,
The gas generating device, wherein the support portion is fixed to the separation membrane. The gas generating device according to claim 2,
The said support part is a gas production | generation apparatus fixed to the said 1st chamber side of the said separation membrane. The gas generator according to any one of claims 1 to 3,
The support portion extends from a first position on the contour indicating the end of the exposed portion along a stretching direction when the separation membrane is bent, and is a second position on the contour different from the first position. A gas generation device including a portion that supports a portion that leads to. A gas generator according to any one of claims 1 to 4,
The reinforcing member is further fixed to the separation membrane, and further includes a seal portion that seals between the separation membrane and at least one of the first chamber forming portion or the second chamber forming portion. .

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