JPS6341990B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing hydrogen, and more specifically, to a novel method for efficiently producing hydrogen at low voltage, which involves performing water electrolysis in an electrolytic cell with a specific electrode arrangement using a cation exchange membrane. . Reflecting the recent energy situation, hydrogen is attracting attention from many quarters as a new energy source to replace oil. Industrial hydrogen production methods can be roughly divided into water electrolysis methods and coke or petroleum gasification methods. Although the former method uses water, which is easily available as a raw material, it requires a large number of electrolysis equipment, is insufficiently adaptable to excess or insufficient current, and deterioration due to carbonation of the electrolyte takes up a lot of floor space.
Many issues remain, including equipment costs. On the other hand,
The latter method is generally complicated to operate, requires fairly large equipment, and has problems such as considerable equipment costs. Furthermore, recently, as an improvement to the water electrolysis method, a fluorine-containing cation exchange membrane having a sulfonic acid group as a cation exchange group has been used, and one side of the ion exchange membrane has a cathode using platinum black as a catalyst, and the other side has a cathode using platinum black as a catalyst. A method has been proposed in which an anode using an alloy of reduced oxides of platinum and ruthenium as a catalyst is closely attached to each surface, and water is electrolyzed to efficiently obtain hydrogen (Japanese Unexamined Patent Application Publication No. 1983-1983).
(See Publication No. 78788, etc.) This method uses porous anodes and cathodes that are permeable to gases and liquids, and is susceptible to electrical resistance caused by the electrolyte and generated hydrogen and oxygen gas, which were previously thought to be unavoidable in this type of technology. Because the electrical resistance due to the underlying bubbles is reduced, it is considered a method that can perform electrolysis at a lower voltage than conventional methods. In this method, the anode and cathode are closely bonded to and embedded in the surface of the ion exchange membrane, and the gas generated by electrolysis at the contact interface between the membrane and the electrode easily leaves the electrode. It is made gas and liquid permeable so that the electrolyte can penetrate. However, when the electrode and ion exchange membrane are directly connected, gas is generated due to the electrode reaction, which causes phenomena such as swelling in the cation exchange membrane and deteriorates the membrane performance, resulting in long-term It was found that this method could not be implemented stably over a period of time. As a result of continued research into electrolysis methods that do not have these disadvantages and have the lowest cell voltage possible, a porous layer that is permeable to gas and liquid and has no electrolytic activity has been developed on the surface of the cation exchange membrane. When water is electrolyzed in an electrolytic cell in which an anode or a cathode is formed, hydrogen and oxygen can be obtained at an unexpectedly low voltage, and the above purpose can be substantially solved. As a result of further study on how to arrange the electrodes, the manufacturing method of the present invention was finally discovered. Thus, the present invention provides a cation exchange membrane having a gas- and liquid-permeable porous layer having no electrode activity on at least one surface, disposed between an anode and a cathode; at least one of the cathodes is a flexible porous electrode having greater rigidity than the cation exchange membrane;
By deforming the flexible electrode, the flexible electrode supplies caustic alkali to the anode side of the water electrolyzer, which is in close contact with the opposing electrode surface via the cation exchange membrane, and water to the cathode side. The gist is a method for producing hydrogen, which is characterized by supplying hydrogen and electrolyzing it. According to the present invention, the electrode is disposed through the gas- and liquid-permeable porous layer, so that it does not come into direct contact with the membrane. Therefore, the electrode is
Since it does not need to be bonded to the membrane or porous layer, it will not be disposed of along with the membrane at the end of its life. In addition, the anode and cathode are provided with a porous layer and placed at a nearly uniform distance between the poles with a cation exchange membrane in between, so there is no localized current flow, and the current density remains constant even locally. . Since the distance between the electrodes is very small, approximately the thickness of the cation exchange membrane, it is naturally expected that the electrolysis voltage will be reduced. Furthermore, the cell voltage according to the present invention is unexpectedly low compared to, for example, a method of electrolyzing water in an electrolytic cell in which the anode or cathode is brought into direct contact with the cation exchange membrane without passing through the porous layer. The voltage drops dramatically. This is because the porous layer is
Unlike the method described in Japanese Patent No. 52-78788, this can be said to be an unexpected effect since it can also be obtained when the layer is formed from a substantially non-conductive particle layer having no electrode activity. The electrode used in the present invention is a porous metal such as a wire mesh or an expanded metal, or a porous metal coated with an electrode active component, and is generally quite thin, with a thickness of about 0.1 to 3 mm. On the other hand, its size is approximately equivalent to the size of the electrode chamber, and if it is large, for example, 1 m
In some cases, it can reach 2 m. Even if the area is smaller than this, thin electrodes as described above can be placed facing each other and close to each other via a cation exchange membrane provided with a porous layer, and the distance between the electrodes can be kept almost constant regardless of the location. It is quite difficult to do. This is because these electrodes have a small thickness relative to their area and are therefore flexible, so they may bend due to pressure fluctuations in the electrolyte, or they may bend during the manufacturing process. . The present inventors solved these problems by making at least one of the electrodes more rigid and flexible than a cation exchange membrane provided with a porous layer,
It has been discovered that the purpose can be fully achieved by deforming the flexible electrode toward the cation exchange membrane. The explanation will be given below based on the drawings. FIG. 1 is a partial cross-sectional explanatory diagram showing an example of the arrangement relationship between a cation exchange membrane provided with a porous layer and an anode and a cathode when carrying out the method of the present invention. (This shows the case where porous layers are provided on both sides of the cation exchange membrane.) 1 is a porous layer attached cation exchange membrane; 11
is a cation exchange membrane, and 12 and 13 are porous layers on the anode side and the cathode side. Reference numeral 2 denotes an anode in which an anode active component is supported on expanded metal, for example, and since it is normally not completely flat, that part is slightly exaggerated and drawn in a curved shape. 3 is a flexible cathode. The arrows shown in FIG. 1 indicate the direction of force applied to the flexible cathode. FIG. 2 is a partial cross-sectional explanatory diagram showing the result of applying force to the flexible cathode in FIG. 1. The porous layer-attached cation exchange membrane is pushed by the flexible cathode, which is deformed by force, and is deformed into the shape of the anode. In this case, since the rigidity of the flexible cathode is greater than the rigidity of the cation exchange membrane attached to the porous layer, both eventually deform to match the shape of the anode, as shown in the figure. If the rigidity is reversed, a gap may be formed between the anode and the cation exchange membrane attached to the porous layer, which is not preferable. Although Figures 1 and 2 show examples in which the porous layer is provided on both sides of the cation exchange membrane, it is not necessarily necessary to provide it on both sides, and depending on the purpose of providing the porous layer described above, It can also be provided on either side. Further, although FIGS. 1 and 2 show the case where the cathode is flexible, it is of course possible that the anode is also flexible. Although it is possible to make both the anode and cathode flexible, it is usually better to make only one of them flexible. According to the experience of the present inventors, when a porous layer is provided on only one side, it seems to be better to provide it on the anode side of the cation exchange membrane. Hereinafter, the present invention will be explained in more detail with respect to a case where porous layers are provided on both sides of a cation exchange membrane and only the cathode is flexible, but it is understood that the present invention does not include only such a case. This is clear from the above explanation. Now, various methods can be considered as means for pressing the flexible cathode in the direction of the porous layer-attached cation exchange membrane. It is a method in which a flexible cathode is pressed against a conductive support. This conductive support is also connected to a negative power source by other conductive means. Preferred examples of the conductive support include rod-shaped or plate-shaped conductive ribs, conductive wavy bodies, conductive net-like bodies, or conductive members having cushioning properties. 3 and 4 show the case where conductive ribs are used, and FIG. 3 is a partial cross-sectional explanatory diagram showing the arrangement relationship of the porous layer-attached cation exchange membrane, anode and cathode, and the conductive rib, FIG. 4 is a partial cross-sectional explanatory view showing a state in which the cathode is pressed in the direction of the porous layer-adhered cation exchange membrane by the conductive ribs. 4
is a conductive rib, which in this case is a plate-shaped body perpendicular to the plane of the paper. This conductive rib 4 is configured to maintain electrical contact with the cathode 3. FIG. 5 shows a case where a conductive corrugated body is used as the conductive support. The conductive corrugated body 5 is placed in electrical contact with the cathode and forces it towards the porous layer attached cation exchange membrane. FIG. 6 shows a case where a conductive network is used as the conductive support. The conductive network 6 is placed in electrical contact with the cathode and forces the cathode towards the porous layer attached cation exchange membrane. FIG. 7 shows a case in which the conductive support is composed of a composite of a conductive network and a conductive wavy body. The conductive multilayer structure 7 is constructed by laminating a conductive network body 71 and conductive wavy bodies 72 and 73.
1, 72, and 73 are maintained in sufficient electrical contact, and this conductive multilayer structure 7 maintains electrical contact with the cathode and extends toward the porous layer-attached cation exchange membrane. Press the cathode. The conductive multilayer structure 7 does not necessarily need to be composed of one conductive net-like body and two conductive wavy bodies, and may be formed by laminating an appropriate number of these bodies. FIGS. 8 and 9 show an example in which the conductive support is a conductive member having cushioning properties. FIG. 8 shows a case where the conductive member having cushioning properties is a spring, and 9 is the spring. FIG. 9 shows a case where the conductive member having cushioning properties is a plate spring, where 9 is a plate spring and 10 is, for example, a flat conductive member. FIGS. 10 and 11 show the case where both the anode and cathode are flexible. FIG. 10 is a partial cross-sectional explanatory diagram showing the arrangement of the porous layer-adhered cation exchange membrane, the flexible anode and cathode, and the conductive support. Since the anodes 2 and 3 placed across the porous layer-attached cation exchange membrane 1 are both flexible, the anode-side conductive support 41 and the cathode-side conductive support 42 do not face each other. It is preferable that they be arranged alternately. FIG. 11 is an explanatory partial cross-sectional view showing a state in which the conductive supports 41 and 42 are deformed by applying force to the conductive supports 41 and 42 in the arrangement shown in FIG. 10, thereby deforming the flexible electrodes and bringing them into close contact with each other. FIG. 12 shows a case where the conductive support is a conductive rod, and both the anode and cathode are flexible. The conductive rods 11 placed in electrical contact with the anode and cathode are preferably placed at staggered positions and not facing each other. In the electrode used in the present invention, platinum group metals, conductive oxides thereof, or conductive reduced oxides thereof, iron group metals, etc. are usually used as anodes, while platinum group metals, conductive oxides thereof are used as cathodes. Or iron group metals etc. are used. In addition, platinum group metals include platinum,
Rhodium, ruthenium, palladium, and iridium are exemplified, and examples of iron group metals include iron, cobalt, nickel, Raney nickel, stabilized Raney nickel, stainless steel, alkali-etched stainless steel (Japanese Patent Publication No. 19229/1983), and Raney nickel cathode (Special Publication No. 19229). (Japanese Patent Application Laid-Open No. 53-115676), Rodan-Nitzkelmecki cathode
etc. are exemplified. If a porous electrode is used, it can be formed from the material itself forming the anode or cathode. However, when platinum group metals or conductive oxides thereof are used, it is preferable to coat the surface of an expanded valve metal such as titanium or tantalum with these substances. On the other hand, the gas- and liquid-permeable, corrosion-resistant porous layer used in the present invention has phosphonic acid groups, sulfonic acid groups, and carboxyl groups, although this varies depending on the type of ion exchange membrane and the type of electrolyte used. When using a fluorine-containing cation exchange membrane containing cation exchange groups and performing electrolysis using an alkaline electrolyte, the periodic table - Group A,
-B group, -B group, iron group metals, chromium, manganese, etc. alone or alloys, oxides, hydroxides, nitrides, or carbides. In addition, when using a fluorine-containing cation exchange membrane containing sulfonic acid groups or phosphonic acid groups as cation exchange groups and performing electrolysis using a neutral or acidic electrolyte, the periodic table -A group, -B
The metal is selected from simple substances or alloys, oxides, nitrides, carbides, etc. of group metals such as group metals, group B, and iron group metals. When forming the porous layer of the present invention from these materials, the above-mentioned materials are used in powder or particulate form, preferably combined with a suspension of a fluorine-containing polymer such as polytetrafluoroethylene. Ru. At this time, if necessary, a porous layer is formed in which a surfactant is used to uniformly mix the two. These mixtures are suitably formed into a layer, and then bonded and preferably embedded by applying pressure and heat to the surface of the ion exchange membrane. In addition, the physical properties of these porous layers are almost the same on both the cathode and anode sides, with an average pore diameter of 0.01~
2000μ, porosity 10-99%, air permeability coefficient 1×10 ^-5
~10 mol/cm ² ·min·cmHg is suitable. If any of these physical properties deviate from the above range, the desired low electrolytic voltage cannot be expected, or
Both are unfavorable because there is a risk that the electrolytic voltage drop phenomenon may become unstable. Among the above physical properties, the average pore diameter is 0.1 to 1000μ, the porosity is 20 to 98%, and the air permeability coefficient is 1×10 ^-4 to 1 mol/cm ²・min・cmHg.
It is preferable to employ this method because stable electrolytic operation can be expected especially at low voltage. In addition, the thickness of such a porous layer is strictly determined by the material used and its physical properties, but generally
It is appropriate to use 0.1 to 500μ, preferably 1 to 300μ. If the thickness deviates from the above range, the electrical resistance may increase, gas may be difficult to escape, or
It is undesirable that the movement of the electrolyte becomes difficult. In the present invention, the anode placed through the porous layer is provided in contact with the surface of the porous layer. In this way, it is provided through a porous layer, and the electrode may be either the anode or the cathode, but
When provided on both the anode side and the cathode side of the ion exchange membrane, it is particularly preferable for lowering the electrolytic cell voltage. In addition, when either the anode or the cathode is provided on the ion exchange membrane via the porous layer of the present invention, the counter electrode has the same composition and shape as in the case of ordinary water electrolysis. Ru. In fact, as a means of providing an electrode through the porous layer, for example, the powder forming the porous layer is applied to the ion exchange membrane by screen printing or the like, and then the ion exchange membrane is bonded with heat and pressure. A method of forming a porous layer on the surface of the porous layer and pressing an electrode against the surface of the porous layer is used. The ion exchange membrane used in the present invention is made of a polymer containing a cation exchange group such as a carboxyl group, a sulfonic acid group, a phosphoric acid group, or a phenolic hydroxyl group, and such a polymer includes a fluorine-containing polymer. It is particularly preferable to adopt Examples of fluorine-containing polymers containing ion exchange groups include vinyl monomers such as tetrafluoroethylene and chlorotrifluoroethylene, and perfluorinated polymers having reactive groups that can be converted into ion exchange groups such as sulfonic acid, carboxylic acid, and phosphoric acid groups. A copolymer of a vinyl monomer with a perfluorinated vinyl monomer having an ion exchange group such as a sulfonic acid, carboxylic acid, or phosphoric acid group is preferably used. Also usable are membrane polymers of trifluorostyrene into which ion exchange groups such as sulfonic acid groups have been introduced, and styrene dibylbenzene into which sulfonic acid groups have been introduced. Among these monomers, it is particularly preferable to use monomers that can form the following polymerized units (a) and (b), since electrolysis can be performed with relatively high current efficiency. (B) (-CF ₂ -CXX′)-, (B)

[Formula] Here, X is fluorine, chlorine, hydrogen or -CF ₃ , X' is X or CF ₃ (CF ₂ ) _n , and m is 1 to 5
, and Y is selected from the following: -PA, -O-(CF ₂ ) _n (P, Q, R) -A where P is (-CF ₂ ) _a (CXX') _b (CF ₂ ) - _c ,
Q is (-CF ₂ -O-CXX')- _d and R is (-
CXX′-O-CF ₂ )-) _e , and (P, Q, R) represents arranging at least one of P, Q, and R in any order. X, X' are the same as above, n=0~1, a,
b, c, d, e are 0-6. A is - COOH,
or -CN, -COF, -COOR, -COOM, -
By hydrolysis or neutralization of CONR ₂ R ₃ , etc., -
Represents a functional group that can be converted to COOH. R ₁ is an alkyl group having 1 to 10 carbon atoms, M is an alkali metal or a quaternary ammonium group, and R ₂ and R ₃ are hydrogen or an alkyl group having 1 to 10 carbon atoms. Preferred representative examples of the above Y have a structure in which A is bonded to carbon containing fluorine, for example,
The following are mentioned. (-CF ₂ )- _x A, -O(-CF ₂ )- _x A,

【formula】

x, y, z are all 1 to 10, and Z, R _f are -
It is a group selected from F or a perfluoroalkyl group having 1 to 10 carbon atoms, and A is the same as above. 1 g of dry resin composed of these copolymers
When using a fluorine-containing cation exchange membrane with a carboxylic acid group concentration in the membrane of 0.5 to 2.5 milliequivalents,
Its current efficiency reaches over 90%. Then, the concentration of carboxylic acid groups in the film per gram of dry resin is
In the case of 1.12 to 2 milliequivalents, electrolysis can be stably continued over a long period of time with high current efficiency, which is particularly preferable. In order to achieve such an ion exchange capacity, in the case of a copolymer consisting of the polymerized units of (a) and (b) above, preferably the polymerized unit of (b) is 1.
~40 mol %, especially 3 to 25 mol % is suitable. Preferred ion exchange membranes used in the present invention are:
From a non-crosslinkable copolymer obtained by copolymerizing the above-mentioned fluorinated olefin monomer with a polymerizable monomer having a carboxylic acid group or a functional group convertible to a carboxylic acid group. The molecular weight thereof is preferably about 100,000 to 2,000,000, particularly 150,000 to 1,000,000. Further, in order to produce such a copolymer, one or more of the above-mentioned monomers may be used, and the resulting film may be modified by further copolymerizing a third monomer. For example, CF ₂ =
By using CFOR _f (R _f is a perfluoroalkyl group having 1 to 10 carbon atoms) in combination, flexibility can be imparted to the obtained film, or CF ₂ =CF−CF=CF ₂ , CF ₂
By using a divinyl monomer such as =CFO(CF ₂ ) _1-3 CF=CF ₂ in combination, the resulting copolymer can be crosslinked and mechanical strength can be imparted to the membrane. Copolymerization of a fluorinated olefin monomer with a polymerizable monomer having a carboxylic acid group or a functional group convertible to the carboxylic acid group, and further with a third monomer,
This can be done by any known means. That is, catalytic polymerization, thermal polymerization, or radiation polymerization can be carried out using a solvent such as a halogenated hydrocarbon, if necessary. Furthermore, there is no particular restriction on the method for forming an ion exchange membrane from the obtained copolymer, such as press molding, roll molding,
Any known means such as extrusion molding, solution casting, dispersion molding, powder molding, etc. may be employed as appropriate. The film thus obtained has a thickness of 20 to 500μ,
Preferably, it is appropriate to make it 50 to 400μ. In addition, if the copolymer is not a carboxylic acid group itself but a functional group that can be converted into a carboxylic acid group before or after the copolymer film formation process, preferably after film formation, by appropriate treatment accordingly. , these functional groups are converted to carboxylic acid groups. For example, --CN, --
COF, ―COOR ₁ , ―COOM, ―CONR ₂ R ₃ (M,
R ₁ to _{R 3} are the same as above), it is converted into a carboxylic acid group by hydrolysis or neutralization with an acid or alkali alcohol solution, and when the functional group is a double bond, -COF It is converted into a carboxylic acid group by reacting with ₂ . Furthermore, the cation exchange membrane used in the present invention may optionally contain an olefin polymer such as polyethylene or polypropylene, preferably polytetrafluoroethylene, or a copolymer of ethylene and tetrafluoroethylene during membrane formation. It can also be molded by mixing fluoropolymer.
Alternatively, it is also possible to reinforce the membrane by using fabrics such as cloth, net, nonwoven fabric, or porous film made of these polymers as a support, or by using metal wires, nets, or porous materials as a support. be. Next, the present invention will be explained by examples. Example 1 Modified polytetrafluoroethylene with a particle size of 1 μm or less (the polytetrafluoroethylene surface was mixed with tetrafluoroethylene and CF ₂ =
Aqueous dispersion containing 7.0% by weight of particles coated with a copolymer of CFOCF ₂ COOCH ₃ (hereinafter referred to as modified PTFE)
2.5 parts and 5 parts of silicon nitride powder having a particle size of 25 μm or less were mixed together and thoroughly mixed in advance, and then 2 parts of isopropyl alcohol and 1 part of cyclohexanol were added and kneaded again to obtain a paste. The paste was applied to a printing substrate with an ion exchange capacity of 1.70meq using a printing plate with a mesh count of 200, a 60μ thick stainless steel screen with an 8μ thick screen mask underneath, and a polyurethane squeegee. /g dry resin, polytetrafluoroethylene with thickness 210μ and CF ₂ =CFO
Screen printing was performed on one side of an ion exchange membrane made of a copolymer of (CF ₂ ) ₃ COOCH ₃ to a size of 20 cm x 25 cm. The printed layer obtained on one side of the ion exchange membrane was dried in air to solidify the paste. On the other hand, silicon nitride having a particle size of 25 μm or less was screen printed on the other side of the ion exchange membrane in exactly the same manner.
Thereafter, the printed layer was pressed onto the ion membrane at a temperature of 140°C and a molding pressure of 30 kg/cm ² , and then immersed in a 25% by weight aqueous potassium hydroxide solution at 90°C to hydrolyze the ion membrane and elute methylcellulose. The silicon nitride layer obtained on the ion exchange membrane has a thickness of 20μ, a porosity of 70%, and a content of titanium oxide of 1.5mg/
^cm2 included. Next, we fabricated a nickel expanded metal anode with an opening size of 6 mm x 13 mm and a plate thickness of 1.5 mm.
A nickel expanded metal with an opening size of 3 mm x 6 mm and a plate thickness of 0.5 mm was used as a cathode, and was arranged as follows as shown in FIGS. 3 and 4. Nickel plates with a thickness of 4 mm were arranged at 10.3 mm intervals as conductive supports, and the tips of the nickel plates were welded to the expanded nickel metal, so that the intervals between the conductive supports were slightly narrowed to 10 mm intervals. The nickel wire mesh cathode was slightly bent and placed as shown in Figure 2. Next, the conductive support was pressed against the anode side as shown in FIG. 3, and then the electrolytic cell was assembled using a known chamber frame using a hollow pipe or the like. Then, by supplying a 30% caustic potassium aqueous solution to the anode chamber of the electrolytic cell and water to the cathode chamber, electrolysis was carried out at 90°C while maintaining the caustic potassium concentration in the anode and catholyte at 20%, and the following results were obtained. I got it. Current density (A/dm ² ) Cell voltage (V) 20 1.70 40 1.90 60 2.11 Example 2 A nickel plate with a thickness of 0.5 mm was used as a conductive support and a corrugated plate with a width of 15 mm and a pitch of 70 mm was used. An electrolytic cell was assembled in the same manner as in Example 1, except that the mountain portion was welded to a nickel expanded metal cathode, and electrolysis was carried out in the same manner as in Example 1. The results were as follows. Current density (A/dm ² ) Cell voltage (V) 20 1.73 40 1.94 60 2.15 Example 3 The following steps were carried out except that a nickel expanded metal cathode was welded at one location per 2 cm ² of 20 mesh nickel wire mesh as a conductive support. Electrolysis was carried out in the same manner as in Example 1. The results were as follows. Current density (A/dm ² ) Cell voltage (V) 20 1.68 40 1.89 60 2.09 Example 4 The same nickel corrugated plate and nickel wire mesh used in Examples 2 and 3 were used as nickel corrugated plate/nickel corrugated plate/ It was laminated with nickel wire mesh and welded to obtain a conductive multilayer structure. Next, the surface of this conductive multilayer structure on the nickel wire mesh side was welded to a nickel expanded metal cathode at one location per 2 cm ² , and an electrolytic cell was assembled in the same manner as in Example 1. 1
Electrolysis was carried out in the same manner. The results were as follows. Current density (A/dm ² ) Cell voltage (V) 20 1.69 40 1.90 60 2.12 Example 5 The anode was made of nickel expanded metal with openings of 3mm x 6mm, and the cathode was made of nickel expanded metal with openings of 3mm x 6mm. A nickel plate with a thickness of 4 mm was welded to this as a conductive support on the anode side, and a nickel plate with a thickness of 4 mm as a conductive support on the cathode side were welded at intervals of 10 cm. Then, these anodes and cathodes were placed between the porous layer-adhered cation exchange membranes produced in the same manner as in Example 1, so that their respective conductive supports were alternately arranged, and the porous layer-adhered cations were I pushed it towards the exchange membrane. Otherwise, assemble the electrolytic cell in the same manner as in Example 1, and
Electrolysis was carried out in the same manner. The results are as follows. Current density (A/dm ² ) Cell voltage (V) 20 1.68 40 1.88 60 2.08

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional explanatory diagram showing the arrangement relationship between a porous layer-adhered cation exchange membrane and an anode and cathode for carrying out the present invention. FIG. 2 is a partial cross-sectional explanatory view showing the result of applying force to the flexible cathode in FIG. 1. FIG. 3 is a partial cross-sectional explanatory diagram showing the arrangement of a porous layer-attached cation exchange membrane and an anode and cathode for carrying out the method of the present invention using conductive ribs as a conductive support. FIG. 4 is a partial cross-sectional explanatory view showing a state in which the cathode is pressed toward the porous layer-attached cation exchange membrane in FIG. 3 by the conductive ribs. FIG. 5 is a partial cross-sectional view showing the arrangement of a porous layer-attached cation exchange membrane and an anode and cathode for carrying out the method of the present invention using a conductive corrugated body as a conductive support. FIG. 6 is a partial cross-sectional explanatory diagram showing the arrangement of a porous layer-attached cation exchange membrane and an anode and cathode for carrying out the method of the present invention using a conductive network as a conductive support. Figure 7 shows the arrangement of the porous layer-adhered cation exchange membrane and anode and cathode for carrying out the method of the present invention, in which the conductive support is a multilayer structure in which a conductive network body and a conductive wavy body are laminated. It is a partial cross-sectional explanatory view showing. FIG. 8 is a partial cross-sectional explanatory diagram showing the arrangement relationship of the anode and cathode of the electrolytic cell for carrying out the present invention, the porous layer-attached cation exchange membrane, and the conductive support having cushioning properties. A case is shown in which a leaf spring is used as a support. FIG. 9 is a partial cross-sectional explanatory diagram showing the arrangement relationship of the anode and cathode of the electrolytic cell for carrying out the present invention, the porous layer-attached cation exchange membrane, and the conductive support having cushioning properties. A case is shown in which a leaf spring is used as a support. Figures 1-9 show the case where only the cathode is flexible. FIG. 10 is a partial cross-sectional explanatory view showing the arrangement of the porous layer-attached ion exchange membrane and the anode and cathode for carrying out the method of the present invention when both the anode and cathode are flexible. FIG. 11 is a partial cross-sectional explanatory view showing a state after deforming the flexible cathode by applying force to the conductive support in FIG. 10. FIG. 12 is a partial cross-sectional explanatory diagram showing the arrangement relationship between the porous layer-attached cation exchange membrane and the anode and cathode for carrying out the method of the present invention when both the anode and cathode are flexible. The case of a conductive rod is shown.

Claims (1)

[Claims] 1. A cation exchange membrane having a gas- and liquid-permeable porous layer with no electrode activity provided on at least one surface is disposed between the anode and the cathode, and at least one of the anode or the cathode is a flexible porous electrode having greater rigidity than the cation exchange membrane;
By deforming the flexible electrode, the flexible electrode supplies caustic alkali to the anode side of the water electrolyzer that is in close contact between the opposing electrodes via the cation exchange membrane, and supplies water to the cathode side. A hydrogen production method characterized by electrolysis without supply. 2. The method for producing hydrogen according to claim 1, wherein the flexible porous electrode is maintained in electrical contact with the conductive support. 3. The method for producing hydrogen according to claim 2, wherein the conductive support is a conductive rib. 4. The method for producing hydrogen according to claim 2, wherein the conductive support is a conductive wavy body. 5. The method for producing hydrogen according to claim 2, wherein the conductive support is a conductive network. 6. The method for producing hydrogen according to claim 2, wherein the conductive support is a conductive multilayer structure formed by laminating a conductive wavy body and a conductive network body. 7. The method for producing hydrogen according to claim 2, wherein the conductive support is a conductive member having cushioning properties. 8. The method for producing hydrogen according to claim 1, wherein both the anode and the cathode are flexible, and the conductive supports supporting the anode and the cathode are arranged alternately so that they do not face each other.