CN112534086A

CN112534086A - Conductive elastomer for electrolytic cell and electrolytic cell

Info

Publication number: CN112534086A
Application number: CN201980049638.5A
Authority: CN
Inventors: 浅海清人; 长濑学; 羽多野聪; 角井谕
Original assignee: Osaka Soda Co Ltd
Current assignee: Osaka Soda Co Ltd
Priority date: 2018-07-27
Filing date: 2019-07-25
Publication date: 2021-03-19
Also published as: WO2020022440A1; JP7473039B2; JP2023053356A; JPWO2020022440A1; JP7298616B2

Abstract

The invention provides a conductive elastomer for an electrolytic cell, which comprises a fixed part and a plurality of elastic parts extending from the fixed part. In the conductive elastic body, each of the plurality of elastic portions is curved in a wavy manner, and the plurality of elastic portions are alternately arranged in a staggered manner.

Description

Conductive elastomer for electrolytic cell and electrolytic cell

Technical Field

The present invention relates to a conductive elastomer for an electrolytic cell and an electrolytic cell.

Background

The electrolytic cell is a cell for performing electrolysis, and includes at least an anode and a cathode. For example, a cell in which an aqueous sodium chloride solution is electrolyzed is used for producing chemical raw materials because chlorine, hydrogen, and sodium hydroxide (so-called caustic soda) can be produced. In such an electrolytic cell, a diaphragm such as an ion exchange membrane is usually provided to avoid mixing of the substance produced at the anode and the substance produced at the cathode. The process of electrolyzing an aqueous sodium chloride solution using an ion exchange membrane is also referred to as "ion exchange membrane method salt electrolysis" or the like.

In the field of salt electrolysis by an ion exchange membrane method, there are various types of electrolytic cells, and the zero-pole pitch type is becoming the mainstream. In the zero-pole-pitch type electrolytic cell, the anode, the diaphragm and the cathode are closely attached to each other, so that the distance between the electrodes is shortened, and the resistance of the electrolyte is reduced. Therefore, the use of such an electrolytic cell reduces power consumption.

Documents of the prior art

Patent document

Patent document 1: international publication (WO) No. 2012/091051

Patent document 2: japanese patent No. 5108043

Patent document 3: japanese patent No. 5970250

Disclosure of Invention

Technical problem to be solved

The inventor of the present invention has noticed that the existing electrolytic cell still has the technical problems to be solved, and has found necessary to take measures for this purpose. Specifically, the following technical problems are found.

In the "zero-pitch" electrolytic cell, it is considered that one of the anode and the cathode has higher rigidity than the other, and the other is relatively soft and has higher flexibility. More specifically, one electrode is made to have a rigid structure in which the rigidity is high and the deformation is small even if the electrode is pressed against the separator, and the other electrode is made to have a soft flexible structure capable of absorbing the tolerance of the electrode holder or the like and the unevenness due to the deformation. In this case, by adopting a design in which a conductive elastic body is provided on the back side of the flexible electrode, it is possible to provide a pressure necessary for bringing the cathode, the separator, and the anode into close contact with each other by utilizing the elastic force (i.e., the reaction force) of the conductive elastic body.

The inventors have found that a desired electrolytic cell may not be obtained due to the conductive elastomer. Specifically, a coil type spring body (see, for example, patent documents 1 to 3) may be used as the conductive elastic body for a required elastic force, but in this case, the diaphragm may be damaged. This is because the wire of the coil or the like is easily broken due to its small diameter, and when the breakage occurs, a relatively sharply protruding form is easily generated. Further, the form of the conductive elastomer itself also affects the operation of the electrolytic cell, and there is room for improvement particularly in terms of energization during operation.

The present invention has been made in view of the above problems. That is, a main object of the present invention is to provide an electrolytic cell technology capable of reducing the possibility of damaging a separator with respect to a conductive elastomer and contributing to more desirable energization at the time of electrolytic operation.

(II) technical scheme

The inventor does not follow the prior art, but solves the technical problems through a brand new thought. As a result, the conductive elastomer which achieves the above-described main object has been invented.

The present invention provides a conductive elastomer for an electrolytic cell, which comprises:

a fixed portion and a plurality of elastic portions extending from the fixed portion,

the plurality of elastic parts are respectively bent in a wave shape,

in the plurality of elastic portions, the wavy bends are alternately arranged in a staggered manner.

(III) advantageous effects

The conductive elastomer of the present invention can provide an electrolytic cell which reduces the possibility of damage to the separator and contributes to more desirable energization in electrolytic operation.

Specifically, the conductive elastic body of the present invention is a plate spring type having a skeleton structure of the fixed portion and the plurality of elastic portions, and therefore, is less likely to be broken when the electrolytic cell is used. In the conductive elastic body of the present invention, each of the plurality of elastic portions is curved in a wave-like manner, and the wave-like shape is not arranged in alignment along the longitudinal direction of the fixed portion. Therefore, the contact between the conductive elastomer and the electrode is more suitable for the current distribution during electrolytic operation. In particular, the contact between the conductive elastomer and the electrode is likely to be a so-called "staggered grid" contact. This makes it less likely to cause a deviation in the flow of current, and enables a more uniform current distribution as a whole to be obtained. Therefore, the electrolysis voltage during the electrolysis operation is reduced as a whole, and the operation of the electrolytic cell is more efficient. In addition, voltage drop due to structural resistance of the cathode can be reduced.

Drawings

Fig. 1 is a schematic diagram for explaining an exemplary embodiment in the case of using a conductive elastic body.

Fig. 2 is a schematic perspective view of a conductive elastic body provided as an embodiment of the present invention.

Fig. 3 is a schematic plan view of a conductive elastomer provided as an embodiment of the present invention.

Fig. 4 is a schematic plan view showing a contact between the conductive elastomer and the electrode in the electrolytic cell (a "contact in a staggered lattice pattern").

Fig. 5 is a schematic perspective view of a conductive elastomer provided as another embodiment of the present invention.

Fig. 6 is a schematic plan view of the conductive elastomer of fig. 5.

Fig. 7 is a schematic view for explaining an extension angle.

Fig. 8 is a schematic perspective view illustrating an electrolytic cell unit on the anode side.

Fig. 9 is a schematic perspective view of the electrolytic cell unit illustrating the cathode side.

FIG. 10 is a schematic perspective view for explaining the combination of the electrolytic cell units with the ion exchange membrane interposed therebetween.

Fig. 11 is a partially enlarged schematic view of an expansion alloy for explaining the width dimension (W) of the strands.

Fig. 12 is a schematic cross-sectional view in the horizontal direction of an electrolytic cell provided with a conductive elastomer.

Fig. 13 is a schematic perspective view of a conductive elastomer provided as another embodiment of the present invention.

Fig. 14 is a schematic plan view of the conductive elastomer of fig. 13.

Fig. 15 is a schematic perspective view of a conductive elastomer provided as another embodiment of the present invention.

Fig. 16 is a schematic plan view of the conductive elastomer of fig. 15.

Fig. 17A is a schematic perspective view of a conductive elastomer provided as another embodiment of the present invention.

Fig. 17B is a schematic plan view of the conductive elastomer of fig. 17A.

Fig. 18A is a schematic perspective view of a conductive elastomer provided as another embodiment of the present invention.

Fig. 18B is a schematic plan view of the conductive elastomer of fig. 18A.

Fig. 19 is a schematic perspective view of a comparative example (comparative example in the proof test) exemplified for comparison with the present invention.

Fig. 20 is a graph showing the results of an experimental test carried out for the present invention.

Detailed Description

The "conductive elastomer for electrolytic cell" and the "electrolytic cell" according to one embodiment of the present invention will be described in more detail below with reference to the drawings. The various elements in the drawings are shown schematically and illustratively for the understanding of the present invention, and may differ from actual ones in appearance, size ratio, etc.

In the present specification, the term "electrolytic cell" refers to a cell for carrying out electrolysis, and in a narrow sense refers to a cell including at least an anode, a cathode, and a separator provided between these electrodes, as represented by an electrolytic cell or the like.

In the present specification, the "vertical" direction, which is directly or indirectly described, is mainly based on the direction of the acting elastic force in the description of the conductive elastic electrolytic cell. More specifically, when the conductive elastic body is placed on a plane, that is, when the fixing portion (a portion which becomes a shaft or a main frame described later) is placed in contact with the plane, a direction away from the plane corresponds to an "upper direction", and a reverse direction corresponds to a "lower direction". In short, based on the directions in the form shown in fig. 2 and the like, "upper direction" and "lower direction" in the drawings correspond to the upper direction and the lower direction of the conductive elastic body, respectively, and the same applies to the left and right directions. In addition, in the electrolytic cell, the conductive elastic body may be provided in such a manner that the axis thereof is vertical, and therefore, in the explanation about the electrolytic cell, the direction based on such a usage manner is followed. That is, in the explanation of the electrolytic cell, the direction in the vertical upward direction corresponds to the "upward direction" and the reverse direction corresponds to the "downward direction".

The various numerical ranges mentioned in this specification also include the lower and upper numerical values themselves. That is, for example, if a numerical range of 1 to 10 is taken as an example, the explanation is that "1" including the lower limit value and "10" including the upper limit value are included.

[ conductive elastomer of the present invention ]

The conductive elastomer of the present invention is used for an electrolytic cell. That is, an elastomer for use in an electrolytic cell. In particular, a conductive elastomer is used in an electrolytic cell including an anode, a cathode, and an ion exchange membrane disposed between these electrodes. The conductive elastomer of the present invention contributes to the electrical conduction between electrodes in an electrolytic cell due to its "conductivity", and can exert a pressing force on the electrodes due to its "elasticity".

Fig. 1 schematically shows an exemplary embodiment of the use of the conductive elastomer. As shown in the drawing, the conductive elastomer of the present invention is used for an electrode assembly composed of at least an anode, a cathode, and an ion exchange membrane between these electrodes. Specifically, the electrolytic cell is used in a state where the conductive elastic body is elastically deformed on the back surface side of the electrode assembly, and the pressing force is applied to the electrode assembly by the elastic force (i.e., the reaction force) provided by the conductive elastic body. In particular, the conductive elastic body that is elastically deformed acts so as to apply a pressing force from one electrode to the other electrode, thereby promoting adhesion of the electrode assembly. That is, the presence of the conductive elastomer brings the anode, the ion exchange membrane, and the cathode into close contact with each other, and the electrolytic cell can function appropriately as a so-called "zero pole pitch" type.

From the above description, it can be seen that: the conductive elastomer of the present invention corresponds to a conductive member capable of exhibiting a reaction force in an electrolytic cell, and has at least a structure capable of elastic deformation in order to provide the reaction force. In a preferred embodiment, the conductive elastomer of the present invention is made of metal from the viewpoint of both "elastically deformable structure" and "conductivity". For example, the conductive elastomer may be formed using a base material composed of at least one selected from the group consisting of titanium, nickel, stainless steel, iron, copper, and alloys thereof. Further, the conductive elastomer is not limited to metal and may be carbon, and therefore, the conductive elastomer may be configured by using carbon in addition to or instead of metal. In addition, an electrolysis reaction catalyst may be added to such a base material (for example, in the case where the electrolytic cell is an electrolytic cell for salt electrolysis, the base material may be coated with a platinum group metal or the like, or the conductive elastomer may be provided with a function of a hydrogen generation catalyst or the like).

Fig. 2 and 3 show an exemplary embodiment of the conductive elastomer of the present invention. The conductive elastomer 100 of the present invention includes: a fixed portion 10 and a plurality of elastic portions 20 extending from the fixed portion. As shown in the drawing, in the conductive elastic body 100, the fixed portion 10 constitutes a core or a shaft of a member, and the elastic portion 20 is branched from the fixed portion 10 to constitute an integral skeleton.

The fixing portion 10 is preferably an elongated member. That is, the fixing portion 10 has a form extending long in a certain direction. In addition, the fixing portion 10 preferably extends in a plane, and particularly does not have a curved form. That is, the fixing portion 10 has a flat shape.

On the other hand, the elastic portion 20 extends non-planarly, and thus has a curved form. The plurality of elastic portions 20 are provided to extend from a plurality of positions along the longitudinal direction of the fixing portion 10 (particularly, from the side portions of the fixing portion 10). As shown in the drawing, each of the plurality of elastic portions 20 is provided to extend laterally from the fixing portion 10 having a planar form, but the extension is accompanied by bending. The plurality of elastic portions may extend from only one side portion (one side) of the fixing portion, or may extend from both side portions (both sides) of the fixing portion, respectively, as illustrated.

In the conductive elastic body 100, the fixed portion 10 and the elastic portion 20 are preferably integrated with each other. In this integrated product, the fixed portion 10 has a non-bent form, and the elastic portion 20 has a bent form. In a preferred embodiment, as shown in fig. 2 and 3, the elastic portion 20 in the bent form extends in a direction orthogonal to the longitudinal direction of the fixed portion 10 in the non-bent form in a plan view.

From the above description, it can be seen that: the "fixed portion" in the present specification means a main frame portion of a shaft or a base which becomes a component. On the other hand, the "elastic portion" refers to a sub-skeleton portion provided so as to extend or branch from the portion serving as the shaft or the base. Therefore, the width dimension of the fixing portion (fixing portion) is preferably larger than the width dimension of the elastic portion (elastic portion) in comparison with the width dimension of the fixing portion (short side dimension of the conductive elastic body in a plan view). As can be seen from fig. 3 and the like, the fixing portion 10 and the elastic portion 20 in the present invention may be referred to as "trunk members" and "branch members" respectively, in terms of the overall shape of the conductive elastic body 100.

The conductive elastic body 100 of the present invention is characterized by the bending form of the elastic portion 20, and particularly, by the bending form of the entire plurality of elastic portions. Specifically, in the conductive elastic body 100 of the present invention, each of the plurality of elastic portions is curved in a wavy manner, and the curved portions of the plurality of elastic portions are alternately arranged in a staggered manner. In particular, when a plurality of elastic portions 20 are provided along the longitudinal direction of the fixed portion 10, the same wavy bends are alternately arranged in a staggered manner.

The wavy curve of each elastic portion contributes to the manifestation of the spring characteristics of the conductive elastic body 100. That is, when an external force acts on the elastic portion, the elastic portion can be elastically deformed by changing the way of the wavy curve, and the spring characteristic of the conductive elastic body 100 can be exhibited. More specifically, when the elastic portion is deformed so as to reduce the wavy curve (or so as to flatten) by an external force, stress for restoring the original shape acts on the conductive elastic body, and spring characteristics are exhibited. For example, when the ridges and/or valleys are provided in the respective elastic portions by the wavy bend, and such ridges and/or valleys are deformed so that the height or depth thereof is reduced and the deformation is maintained, stress that restores the original shape of the ridges and/or valleys acts, and thus a reaction force can be developed.

As shown in the drawing, when viewed along the longitudinal direction of the fixed portion, the plurality of elastic portions are not all aligned in a wavy curve. In fig. 19, the plurality of elastic portions are all aligned in the form of a wavy bend along the longitudinal direction of the fixed portion, but this "all aligned" is not the case in the present invention. As can be seen from the embodiment shown in fig. 2, in the elastic portion 20 of the conductive elastic body 100 according to the present invention, the peaks and/or valleys caused by the wavy meandering are not aligned completely (in particular, the conductive elastic body is in a state in which the peaks or valleys of all the plurality of elastic portions 20 are aligned along a straight line in the longitudinal direction of the fixing portion when viewed in a plan view).

In the conductive elastic body of the present invention, the elastic portions adjacent to each other may have different arrangement states of the crest portions caused by the wavy curve. In particular, for the elastic portions adjacent to each other, the peak portions (particularly, peak points thereof) caused by the wavy flexure may be arranged so that the separation distances from the fixing portion are different from each other. Also, for the elastic portions adjacent to each other, the valleys caused by the wavy bend may be arranged states different from each other. In particular, in the case of the elastic portions adjacent to each other, the valleys caused by the wavy bend (particularly, the valley bottom points thereof) may be arranged so that the separation distances from the fixing portion are different from each other.

Such "arrangement of the alternately staggered wavy beads" of the plurality of elastic portions is desirable for energization when a conductive elastic body is used. Specifically, the contact between the conductive elastomer and the electrode is more suitable for the current distribution during electrolytic operation. As shown in fig. 1, the elastically deformed conductive elastic body acts to press the electrodes from one electrode to the other electrode, and the elastic body itself has conductivity, and therefore, is advantageous for a current path during electrolysis. In an electrolytic cell using a conductive elastomer, an electric current flows through a contact between the conductive elastomer and an electrode, and the electrode is caused to react by applying such an electric current, thereby obtaining a desired electrolytic product. For example, in an electrolytic cell for salt electrolysis, chlorine gas, hydrogen gas, and caustic soda are obtained by an electrode reaction that occurs with energization.

The "alternately staggered wavy meandering arrangement" of the present invention contributes to, in particular, the uniformity of the energization and the reduction of the voltage drop due to the structural resistance of the cathode. This is because, as shown in fig. 4, the contact (indicated by an "x" in the figure) between the conductive elastic body and the electrode is likely to be a so-called "staggered lattice-like" contact. Since the conductive elastomer is formed in a "staggered lattice shape", the contact between the conductive elastomer and the electrode can be a more regular and/or dense contact. In other words, in the conductive elastic body 100 of the present invention, variations in the flow of current are less likely to occur, a more uniform current distribution is likely to be formed as a whole, and a voltage drop due to the structural resistance of the cathode can be reduced. Therefore, in the electrolytic cell using the conductive elastomer of the present invention, the electrolytic voltage at the time of electrolytic operation is reduced as a whole, and the operation of the electrolytic cell is more efficient. In addition, in each elastic portion, at least two peaks caused by wavy bends may be provided. Likewise, in each elastic portion, at least two valley portions caused by wavy bends may be provided. The crest and trough of each elastic portion may share a part of them. In addition, at least two peaks may be the same shape as each other, and likewise, at least two valleys may be the same shape as each other. In addition, in each elastic portion, the peak levels of the plurality of peaks may be substantially all the same, and/or the valley levels of the plurality of valleys may be substantially all the same (the peak level/valley level may be the same between the plurality of elastic portions). Due to the characteristics of the elastic portions, the contacts between the conductive elastic body and the electrodes are arranged in a staggered manner, and a more regular contact or a denser contact is easily adopted.

In a preferred embodiment of the conductive elastic body, the crest portions caused by the wavy bend are aligned in every other elastic portion along the longitudinal direction of the fixing portion. That is, when the plurality of elastic portions are viewed in one straight line direction along the longitudinal direction of the fixing portion, the crest portions caused by the wavy curve appear every other. Thus, the contact between the conductive elastomer and the electrode easily forms a "cross-grid" contact, and a more uniform current distribution can be formed during operation of the electrolytic cell, thereby reducing a voltage drop due to the structural resistance of the cathode.

Similarly, in a preferred embodiment of the conductive elastic body, the trough portions caused by the wavy bend are aligned every other elastic portion so as to extend along the longitudinal direction of the fixed portion. That is, when the plurality of elastic portions are viewed in one straight line direction along the longitudinal direction of the fixed portion, the valley portions caused by the wavy curve appear every other. Thus, the contact between the conductive elastomer and the electrode easily forms a "cross-grid" contact, and a more uniform current distribution can be formed during operation of the electrolytic cell, thereby reducing a voltage drop due to the structural resistance of the cathode.

In addition, if viewed from another angle, among the elastic portions adjacent to each other, "peaks of one elastic portion caused by undulation" and "valleys of another elastic portion caused by undulation" may be adjacent to each other along the long-side direction of the fixing portion. In the case where a plurality of elastic portions are viewed in one straight line direction along the longitudinal direction of the fixing portion, "crests" and "troughs" caused by the wavy curve may alternately appear. That is, in the conductive elastic body, in a plan view, the "peaks" caused by the wavy meandering may be arranged in a staggered lattice, and the "valleys" caused by the wavy meandering may be similarly arranged in a staggered lattice. In the case where the conductive elastomer is used in an electrolytic cell, the "crest portion" (particularly, the crest point thereof) of the wavy curve or the "trough portion" (particularly, the trough bottom point thereof) of the wavy curve can be a contact with the electrode, and therefore, the "staggered grid-like" contact is easily formed, a more uniform current distribution is easily obtained at the time of operation of the electrolytic cell, and a voltage drop due to the structural resistance of the cathode is reduced.

In the conductive elastic body of the present invention, preferably, the foremost end (the foremost end side or the distal end side in the extending direction) of each elastic portion and the electrode do not form a contact. This means that: the foremost end of each elastic portion (the portion closest to the peripheral edge, which is the outermost conductive elastic body) is not located at the uppermost horizontal position. Further, the foremost ends of the elastic portions may be aligned in the plurality of elastic portions (that is, as shown in fig. 3, the foremost end points of the plurality of elastic portions may be aligned in the longitudinal direction of the fixing portion in a plan view).

In one aspect, the separation distance between the plurality of elastic portions is appropriately adjusted. In particular, as is apparent from the plan view shown in fig. 3, for example, the gap dimension between the adjacent elastic portions (i.e., the gap dimension along the longitudinal direction of the fixed portion) is smaller than the width dimension of the elastic portion (i.e., the short side dimension of the elastic portion along the longitudinal direction of the fixed portion). Therefore, the "staggered grid" contact points can be made denser, and thus a more appropriate current distribution can be easily obtained during operation of the electrolytic cell.

The conductive elastomer of the present invention can also adopt a form characterized particularly in terms of "elastic properties". This will be described in detail below with reference to fig. 5 to 7.

< conductive elastomer characterized by elastic Properties >

The conductive elastic body 100 has the embodiments shown in fig. 5 to 7 as representative figures, and is characterized by its elastic characteristics. Is characterized in particular by the elastic properties of the elastic portion 20 extending from the fixed portion 10. Specifically, at least one of the plurality of elastic portions is a double elastic portion exhibiting both a first elasticity provided as a local elastic characteristic and a second elasticity provided as a wide-range elastic characteristic.

That is, the conductive elastic body 100 of the present invention can provide an elastic body in which one elastic portion 20 (i.e., a double elastic portion) exhibits two different elastic characteristics. The elasticity is a property of restoring its original shape when an external force is removed when it is deformed by the external force, and thus means that the double elastic portion 20 exhibits two different spring characteristics. Therefore, in the present invention, the "double elastic portion" may be referred to as a "double elastic portion", or the like.

Here, the term "local elastic properties" as used herein does not mean elastic properties exhibited by the whole of the double elastic portion of the electrically elastic body, but means elastic properties exhibited by a certain portion of the double elastic portion. On the other hand, the "wide range of elastic properties" referred to in the present specification means not the elastic properties exhibited by a certain portion of the double elastic portion of the conductive elastic body but the elastic properties exhibited by the whole of the double elastic portion.

Without being limited to a particular theory, the "wide range elastic characteristic" is an elastic characteristic exhibited by the entire bielastic part, and therefore plastic deformation is particularly unlikely to occur, and a spring force that is unlikely to soften over time can be exhibited in cooperation with the "local elastic characteristic". That is, in the conductive elastic body, even if the deformed state of the conductive elastic body is maintained for a long time in order to develop the reaction force, "fatigue" is not likely to occur, and a desired elastic force can be maintained for a longer time. Therefore, in the electrolytic cell using such a conductive elastic body, a problem such as an increase in power consumption due to a decrease in elastic force is less likely to occur, and a desired electrolytic operation can be maintained for a longer period of time.

In a preferred embodiment, the first elasticity is based on a partial shape of the bielastic part, and the second elasticity is based on an overall extension of the bielastic part. Specifically, the first elasticity is based on the respective shapes of the dual elastic portions (particularly, the shapes that constitute the outlines of the elastic portions), while the second elasticity is based on the respective extension forms of the dual elastic portions (particularly, the relative extension forms with respect to the fixed portion). This means that: the extension of each of the bielastic elements, which is mainly associated with the "wide range of elastic properties", and the contour of each of the bielastic elements, which is mainly associated with the "local elastic properties", cooperate with each other to exhibit a reaction force that is less prone to fatigue over time.

The conductive elastomer characterized particularly in elastic properties is completed in view of the reduction of elastic force. Specifically, when the electrolytic cell is used, the conductive elastic body is constantly kept pressed from the surroundings to exhibit the elastic force, and therefore the elastic force is reduced with time, and there is a possibility that the normal operation of the electrolytic cell is affected. In contrast, the "conductive elastomer characterized by elastic properties" of the present invention has a low possibility of damaging the separator, and therefore, an electrolytic cell in which the elastic force is maintained in an appropriate state over time can be realized.

Specifically, the "conductive elastic body characterized by elastic properties" is a plate spring type in which the fixed portion and the plurality of elastic portions have a skeleton structure, and therefore, is less likely to break when the electrolytic cell is used. Further, the conductive elastic body of the present invention exhibits both the first elasticity provided as the local elastic characteristic and the second elasticity provided as the wide-range elastic characteristic, and therefore can exhibit a preferable elastic force over time. In particular, even if the conductive elastic body is constantly kept pressed from the surroundings in order to develop the elastic force when the electrolytic cell is used, "fatigue" is less likely to occur, and a desired elastic force can be maintained for a long time. That is, in the electrolytic cell including the conductive elastomer of the present invention, a problem such as an increase in power consumption due to a decrease in elastic force is less likely to occur, and a desired electrolytic operation can be maintained for a longer period of time.

The "conductive elastomer having characteristics particularly in terms of elastic properties" will be described more specifically by taking the mode shown in fig. 5 and 6 as an example. In the illustrated conductive elastic body 100, the double elastic portion 20 is formed to have a wavy curve, and is provided to have an extending angle with respect to the main surface of the fixing portion 10 as a whole. That is, in each of the bielastic parts 20, a crest and/or a trough is provided in each elastic part due to the wavy bend, and the bielastic part 20 as a whole extends obliquely (in particular, extends obliquely with respect to the plane constituted by the principal surface of the fixed part).

In such a conductive elastic body 100, the first elasticity is elasticity caused by wavy bending. That is, the first elasticity, which is a local elastic characteristic, is caused by the wavy curve of each of the bielastic parts 20, that is, by local peaks and/or valleys of each of the bielastic parts 20. When the peaks and/or valleys of each elastic portion are deformed so that the height or depth thereof is reduced and the deformed state is maintained, stress that restores the original shape of the peaks and/or valleys acts, and thus a reaction force (i.e., first elasticity) can be exhibited.

On the other hand, the second elasticity is elasticity due to the extension angle of the bielastic part 20 with respect to the main surface of the fixed part 10. That is, the second elasticity, which is the elastic characteristic in a wide range, is caused by the angle α (0 ° < α < 90 °) of each of the bielastic parts 20 with respect to the plane formed by the principal surfaces of the fixed part 10. When the elastic portions are deformed so that the elongation angle of each elastic portion is reduced and the deformation is maintained, a stress for restoring the original elongation angle α is applied, and thus a reaction force (i.e., second elasticity) can be exhibited.

The extension angle may be such that the bielastic part is bent so as to form an extension angle with a boundary between the bielastic part and the fixed part as a starting point. That is, the bielastic part 20 can be said to be bent so as to form an extending angle from the root portion at which it extends. As a result, the second elasticity is exhibited substantially as a whole in the elastic portion 20, and a conductive elastic body less likely to cause "fatigue" can be obtained. For comparison, fig. 19 shows a mode in which the angle is not extended. That is, the embodiment shown in fig. 19 corresponds to an arrangement in which the elastic portion as a whole does not form an extension angle with respect to the main surface of the fixed portion (the angle α described above corresponds to α being 0 °). In the embodiment shown in fig. 19, since the "extension angle" is not formed with respect to the main surface of the fixing portion, when the conductive elastic body is deformed (particularly, when the conductive elastic body is deformed by an external force acting in the vertical direction in the illustrated embodiment), the elastic portions are deformed so that the crests and/or troughs of the elastic portions are reduced, but are not deformed so that the extension angle is reduced. In contrast, in the conductive elastic body of the present invention shown in fig. 5, when deformed similarly, the elastic portions are deformed so that not only the ridges and/or valleys of the elastic portions are reduced, but also the extension angle is reduced. Therefore, in the conductive elastic body of the present invention, not only the first elasticity based on the local shape of the elastic portion but also the second elasticity based on the overall extension form of the elastic portion is exhibited.

The "extending angle" referred to in the present specification means an angle formed by the extending direction of the entire bielastic part and the "plane formed by the fixed part". In short, the angle α shown in fig. 7. That is, an angle formed by a straight line connecting the starting point of the elastic portion and the lowest point of the wavy curve of the elastic portion (particularly, the lowest point closest to the trough portion of the fixed portion) with respect to the "plane constituted by the fixed portion" corresponds to the extension angle α. Although not particularly limited, the extension angle of the bielastic portion is preferably in the range of 1 ° to 45 °, and may be, for example, about 5 ° to 30 ° or about 10 ° to 30 °. If the extension angle is smaller than 1 °, the second elasticity of the extension form based on the integrity of the elastic portion is not substantially exhibited, and if the extension angle is too large, the dimension becomes too large, and it becomes difficult to deform in a manner of reducing the extension angle in use. Therefore, in order to ensure both the second characteristic and the smooth deformation during use, the extension angle of the bielastic part is preferably in the range of 1 ° to 45 °.

As can be seen from the embodiment shown in fig. 5, at least two peaks caused by the wavy bend may be provided in the bielastic portion. The ridges correspond to the local shape of the elastic portion, and by providing at least two ridges in relation to the development of the first elasticity, the pressure required to bring the anode, the separator, and the cathode into close contact with each other can be more easily provided by the spring force of the conductive elastic body. In addition, in the double elastic portion, at least two valleys caused by the wavy bend may be provided. The valley portions also correspond to the local shape of the elastic portion, and in connection with the development of the first elasticity, by providing at least two valley portions, the pressure required to bring the anode, the separator, and the cathode into close contact with each other can be easily provided by the reaction force of the conductive elastic body. In addition, providing at least two crests and/or troughs caused by the wavy bend increases the extension length of the elastic portion, and as the extension length increases, the elastic portion as a whole is less likely to be plastically deformed. Thus, the provision of at least two peaks and/or valleys also makes it easier to develop the second elasticity as a large range of elastic properties. In a preferred manner, in the bielastic part, due to the "extension angle" it is: the peak top levels of the plurality of crests gradually increase toward the outside, and/or the valley bottom levels of the plurality of valleys (i.e., the "lowest point of the valley" described above) gradually increase toward the outside. In addition, the crest and the trough of each elastic portion may share a part of them. In addition, at least two of the crests may have the same shape as each other, and similarly, at least two of the troughs may have the same shape as each other. This is because the contact between the conductive elastic body and the electrode is easily arranged in a staggered manner to be a more regular contact or a denser contact.

The conductive elastic body of the present invention can be realized in various forms, regardless of whether it is an elastic body characterized particularly in terms of elastic properties as described above. This will be explained below.

(elastic parts of paired type)

The conductive elastic body of the present invention may be provided as a pair of elastic portions extending from the fixed portion. For example, as shown in fig. 2, 3, 5, and 6, the plurality of elastic portions 20 may be paired so as to extend from a plurality of positions of the fixed portion 10 in the longitudinal direction in the opposite direction to each other. In this "paired" manner, the conductive elastomer can provide a reaction force over a wider range. That is, the conductive elastic body using the mode of the elastic portion pair can function to press from one electrode to the other electrode in the electrolytic cell to bring the electrode assembly into close contact with each other, and in this case, the pressing force can act in a wider range of the electrodes. This feature is particularly suitable when the electrolytic cell is large and the size of the main surface of the electrode to be pressed is large to realize a zero pole pitch.

In the mode in which the elastic portions are paired, the elastic portions are preferably arranged to have a wavy curve which is symmetrical as a whole. For example, the conductive elastic body may have a configuration in which the crest portions or the trough portions caused by the wavy bend are arranged symmetrically about the fixed portion as the axial center in a plan view. As can be seen from the illustration, for example, the crest (particularly, the crest point) or the trough (particularly, the trough point) caused by the wavy curve may be arranged so as to be line-symmetrical about the fixed portion. This allows the reaction force to be exhibited in a wider range, and the conductive elastic body and the plurality of contacts of the electrode are symmetrical, so that a more uniform current distribution is easily formed when the electrolytic cell is operated. That is, contacts such as "staggered grid" contacts are formed in regular alignment during the operation of the electrolytic cell, and contribute to the reduction of the electrolytic voltage.

(mounting part of conductive elastomer)

The conductive elastomer of the present invention is used in an electrolytic cell, and therefore preferably has a structure suitable for installation in a cell. A method of attaching with a wire or a screw may be used, a method of attaching by welding may be used, and a fixture may be used to improve the workability. For example, as shown in fig. 2, 3, 5, and 6, the fixing portion 10 may be provided with a mounting opening 40. That is, the mounting opening 40 may be provided in a portion that can be the axial center of the conductive elastic body, such as the elongated fixing portion 10. If such an opening is provided, the conductive elastic body 100 can be appropriately attached to the electrolytic cell by an appropriate fixing member 50 through the opening (see fig. 9).

As shown in fig. 2, 3, 5, and 6, the conductive elastic body 100 is not limited to a single mounting opening 40, and may include a plurality of mounting openings. All or as many openings as possible of the plurality of mounting openings may be used when mounting to the electrolysis cell. This enables the conductive elastomer to be more firmly attached. Or only the opening more effective for mounting is selected, so that the conductive elastomer can be mounted more efficiently. That is, since there are a plurality of mounting openings 40, the degree of freedom of mounting to the electrolytic cell is improved. In the conductive elastic body of the present invention, the plurality of mounting openings 40 may be aligned along the longitudinal direction of the fixing portion 10 as shown in the drawing.

(zero polar distance type salt electrolysis cell conductive elastomer)

The conductive elastomer of the present invention is particularly useful for a salt electrolyzer. That is, as a cell utilizing electrolysis, there are various cells for performing melt electrolysis, electrolytic refining, plating, and the like, in addition to an electrolytic cell for producing an electrolytic solution of a desired gas or the like. In these various electrolytic cells, the conductive elastomer of the present invention can also be used as a member for a salt electrolytic cell. More specifically, the resin composition can be used as a conductive elastomer for salt electrolysis by an ion exchange membrane method. In particular, the industrial common salt electrolytic cell may be a large-sized cell, and the present invention may be a conductive elastomer used in such a large-sized cell. In this case, although only an example, the elastic portions of the conductive elastic body are preferably in the above-described "paired form". This is because each single member can provide a pressing force in a wider range. The number of elastic portions provided in a single conductive elastic body is preferably large, and may be, for example, several tens or more, more specifically, about 50 to 1000 (about 25 to 500 pairs if the conductive elastic body is of a "paired type").

The conductive elastomer of the present invention is preferably used in a common salt electrolysis bath, particularly in a zero-pole-pitch common salt electrolysis bath. In this regard, the conductive elastic body provided in the electrolytic cell is pressed from one electrode to the other electrode, and the electrode assembly can be made to closely adhere to each other, which is particularly advantageous for zero pole pitch.

(all-elastic part)

This is a specific implementation only for conductive elastomers characterized in particular by elastic properties, all the elastic portions 20 of which may be double elastic portions. That is, all of the plurality of elastic parts 20 extending from the fixing part 10 may be double elastic parts. As a result, the stress generated when the conductive elastic body is deformed to develop the reaction force can be borne by the plurality of elastic portions, and thus a conductive elastic body that is less likely to cause "fatigue" can be obtained. That is, in the electrolytic cell using such a conductive elastic body, a problem such as an increase in power consumption due to a decrease in elastic force is less likely to occur, and a desired electrolytic operation can be easily maintained over time for a long period of time.

Since all of the elastic portions are double elastic portions, it is preferable that all of the plurality of elastic portions extending from the elastic portion are undulated. Similarly, since all of the elastic portions are double elastic portions, it is preferable that all of the elastic portions extend at an angle (i.e., "extension angle") with respect to the main surface of the fixed portion.

[ electrolytic cell of the present invention ]

Next, the electrolytic cell of the present invention will be described. The electrolytic cell of the present invention has an anode, a cathode, and an ion exchange membrane disposed between these electrodes. The electrolytic cell is provided with the above-described conductive elastic body (particularly, in a large electrolytic cell, a plurality of conductive elastic bodies are provided). Specifically, in the electrolytic cell of the present invention, the conductive elastic body is provided on the back surface side of one of the anode and the cathode so that the one is pressed toward the other.

The electrolytic cell of the present invention is characterized by comprising the conductive elastic body in the "alternately staggered wavy meandering arrangement". That is, the electrolytic cell is provided with the conductive elastic body 100 (see fig. 2 and 3), and in the conductive elastic body 100, the plurality of elastic parts 20 extending from the fixed part 10 in a wavy curve are alternately arranged in a staggered manner.

The conductive elastic body is provided in such a manner as to exhibit spring characteristics. That is, the conductive elastic body is provided in the electrolytic cell in a state of being elastically deformed. More specifically, the conductive elastic body is provided in the electrolytic cell while maintaining a state in which the conductive elastic body is deformed so as to reduce the wavy curve of the elastic portion. The conductive elastic body thus deformed exhibits spring characteristics because a stress for restoring its original shape acts thereon. For example, since the crest and/or the trough are provided in each elastic portion by the wavy bend and the conductive elastic body is provided in a state of being displaced so as to reduce the crest and/or the trough (in particular, displaced so as to reduce the crest height and the trough depth), a reaction force is developed by applying a stress to recover the crest and/or the trough before the displacement.

In the electrolytic cell of the present invention, the reaction force of the conductive elastic body is utilized for pressing the electrode assembly composed of at least the anode, the cathode, and the ion exchange membrane between these electrodes. In particular, the reaction force is used for pressing the electrodes, thereby realizing a so-called "zero pole pitch" of the electrolytic cell. That is, a force pressing from one electrode toward the other electrode by the reaction force of the conductive elastomer acts, so that close contact, i.e., better adhesion between the anode, the ion exchange membrane, and the cathode, is achieved in the electrode assembly, and a desired "zero pole pitch" is achieved.

In the electrolytic cell of the present invention, the electrode is preferably composed of a conductive base material having liquid permeability. In this regard, at least one of the anode and the cathode preferably has a conductive porous substrate. In other words, at least one of the anode and the cathode is preferably an electrode having mesh openings. Although only an example, at least one of the anode and the cathode is made of, for example, an expanded alloy, a metal mesh (plain mesh, twill mesh), or a punched metal.

In a preferred embodiment, both the anode and the cathode have a conductive porous substrate, for example, both electrodes are made of an expanded alloy or a plain weave mesh, or one electrode is made of an expanded alloy and the other electrode is made of a plain weave mesh. That is, it is preferable that both the anode and the cathode have an expanded mesh or a plain mesh, or that one of the anode and the cathode has an expanded mesh and the other has a plain mesh. As an example, the base materials of the anode and the cathode may be expanded alloys each composed of at least one selected from the group consisting of titanium, nickel, stainless steel, tantalum, zirconium, niobium, and the like, from the viewpoint of corrosion resistance and the like. Similarly, the aperture ratio of the conductive porous substrate is not particularly limited, and may be about 20% to 90%, for example, about 30% to 80%, about 40% to 75%, or about 50% to 75%.

The cell of the invention is preferably of the zero-pitch type, for which the characteristics are better. As one of such characteristics, the anode and the cathode are characterized by so-called "hardness" and "softness" such as rigidity and flexibility of the electrode material. Specifically, one of the anode and the cathode is preferably relatively flexible with respect to the other, that is, conversely, the other is relatively rigid with respect to the one. Thus, the electrode having flexibility can be deflected while receiving the reaction force of the conductive elastic body, and the electrode having rigidity can block the deflection via the ion exchange membrane. As a result, the anode, the ion exchange membrane, and the cathode can be brought into close contact with each other more effectively, and the electrolytic cell can function more effectively as a "zero pole pitch type". This structure is particularly suitable when the electrolytic cell is large (that is, particularly when the main surface of the electrode which needs to be pressed to realize zero-pitch electrolysis, such as the case of zero-pitch salt electrolysis, is large). This will be explained in detail.

In order to obtain a larger amount of desired electrolytic product, a larger electrolytic cell is used, but the main surface of the electrode (particularly, the main surface where the anode and the cathode face each other) becomes larger. The large zero-pole-pitch-type salt electrolyzer is preferably composed of a plurality of electrolyzer units each having a large main electrode surface on each of the opposite side surfaces. For example, in a so-called "multi-pole" salt electrolyzer, an anode (for example, an anode surface 230 made of an expanded alloy, see fig. 8) is provided on one 200A of two opposite side surfaces of the electrolyzer unit 200, and a cathode (for example, a cathode surface 260 made of an expanded alloy, see fig. 9) is provided on the other 200B of the two side surfaces. In the common salt electrolyzer, a plurality of such electrolyzer units are connected to each other so as to overlap each other via an ion exchange membrane 300 (particularly, a cation exchange membrane), and in the adjacent electrolyzer units, the anode surface 230 'of one electrolyzer unit 200' and the cathode surface 260 "of the other electrolyzer unit 200" are overlapped so as to face each other (see fig. 10).

In the electrolytic cell comprising such an electrolytic cell unit, it is preferable that the size of the principal surface of the electrode is large, and the desired electrolytic reaction is carried out by the large electrode surface, but it is difficult to ensure the flatness of the electrode surface. Specifically, the larger the size of the electrode main surface is, the more the influence of the deflection or the like due to its own weight is not negligible, and the influence of the mounting (for example, local welding for mounting) or the like on the electrode support is also affected, and the electrode main surface is difficult to be a completely flat surface. For example, in the electrolytic cell unit 200 (200', 200 ") illustrated in fig. 8 to 10, the size of the main surface of the anode surface and the cathode surface is not in the order of several cm but in the order of m. Even when the electrode is made rigid in order to obtain a preferable flat surface, flatness of the major surface of the electrode is as large as ± 0.5mm to 1.0mm, for example, and it is difficult to obtain a completely flat surface (that is, flatness of 0mm) for the above reasons. In other words, in a large-sized electrolytic cell, the rigid main surface of the electrode tends to be flat in a macroscopic view, but to be a surface having local irregularities in a microscopic view.

If such electrodes having not completely flat surfaces are brought into close contact with each other via the ion exchange membrane, the ion exchange membrane may be damaged by the irregularities, or the uniformity of the current distribution may be impaired. Thus, in a preferred cell of the invention, the electrode paired with the rigid electrode is a softer, flexible electrode relative to the rigid electrode. As a result, even if the electrodes are strongly adhered to each other via the ion exchange membrane, the flexible electrode is bent so as to follow the irregularities of the rigid electrode surface, and damage to the ion exchange membrane, non-uniformity in current distribution, and the like can be prevented well. Although this is merely an example, the anode may be made of a relatively hard rigid expanded alloy, while the cathode may be made of a relatively soft flexible expanded alloy, and the conductive elastic body may be provided on the back side of the flexible expanded alloy of the cathode combined with the rigid expanded alloy of the anode via the ion exchange membrane. In this case, the flexible expansion alloy of the cathode is pressed against the rigid expansion alloy of the anode by the reaction force of the conductive elastomer, but the flexible expansion alloy of the cathode can be locally displaced in accordance with the flatness of the main surface of the rigid expansion alloy of the anode. Therefore, even under the condition that the electrolytic cell units are strongly fastened to each other and the reaction force of the conductive elastic body acts to a large extent, the defects such as damage of the ion exchange membrane and non-uniformity of the current distribution are not likely to occur, and the anode, the ion exchange membrane, and the cathode can be brought into better close contact with each other.

Although not particularly limited, the thickness of the relatively hard and rigid expansion alloy may be preferably in the range of 0.2 to 2.0mm due to "relative rigidity", and the width (step size) (portion indicated by "W" in fig. 11) of the strands constituting the multiple holes, i.e., the openings may be preferably in the range of 0.2 to 2.0 mm. Similarly, although not particularly limited, the flexible expansive alloy may have a thickness of, for example, preferably about 0.1 to 1.0mm, more preferably about 0.1 to 0.5mm, and a width (step size) (portion indicated by "W" in fig. 11) of strands constituting the multiple holes or openings may be preferably about 0.1 to 2.0mm, more preferably about 0.1 to 1.5mm, because of "flexibility in relative terms".

To further understand the invention, FIG. 12 is shown showing a more specific embodiment of the cell. FIG. 12 corresponds to a cross-sectional view of the electrolytic cell of the present invention as viewed from the vertical direction. That is, in the case of the cell of the embodiment shown in fig. 10, this corresponds to a cross-sectional view in the case of cutting the cell (particularly, a combination of the electrolytic cell units) in a lateral direction corresponding to the horizontal direction. In the embodiment shown in fig. 12, the flexible cathode 265 of the expanded alloy, the ion exchange membrane 300, and the rigid anode 235 of the expanded alloy are arranged in this order in an overlapping manner, whereas the conductive elastic body 100 is provided on the back side of the cathode 265 (i.e., on the side opposite to the side where the ion exchange membrane 300 is provided). Since the conductive elastic body 100 is provided so as to be deformed to narrow between the cathode 265 and the cathode base 268 of the expanded alloy (more specifically, a plurality of electrolytic cell units connected to each other are fastened to each other to form such a narrow width and cause deformation of the conductive elastic body), the elastic force of the conductive elastic body 100 directly acts on the flexible cathode 265 of the expanded alloy which is in direct contact with the elastic portion 20 of the conductive elastic body 100. As a result, the flexible cathode 265 of the expanded alloy is urged so as to press the rigid anode 235 of the expanded alloy, and the flexible cathode 265, the ion exchange membrane 300, and the rigid anode 235 are brought into close contact with each other. Further, since the rigid anode itself, which is an electrode not in direct contact with the conductive elastomer, is fixed to an electrode support or the like of the electrolytic cell unit so as not to move, it acts so as to resist the elastic force of the conductive elastomer, and contributes to the realization of close contact. In the electrolytic cell of the present invention, since the plurality of contacts between the elastic portion 20 of the conductive elastomer 100 (particularly, the peak points thereof) and the flexible cathode 265 can be so-called "staggered contacts", a more uniform current distribution can be formed as a whole during operation of the electrolytic cell. That is, the electrolytic cell of the present invention is an excellent zero-pole type electrolytic cell in which the electrolytic voltage is further reduced.

Further details of the electrolytic cell of the present invention (particularly, the conductive elastomer used in the cell), more specific aspects, or other aspects such as an aspect in use are described in the above-mentioned "conductive elastomer of the present invention", and therefore, the description thereof is omitted here to avoid redundancy.

The embodiments of the present invention have been described above, but only typical examples of the range of application of the present invention are shown. Therefore, the present invention is not limited to the above-described embodiments, and those skilled in the art can easily understand that various modifications can be made without departing from the scope of the present invention.

For example, in the above description, the salt electrolyzer is referred to as a "multi-pole type" as a plurality of electrolyzer units, but the present invention is not limited thereto. That is, the electrode layer unit of the common salt electrolyzer is not limited to the multi-pole type electrolyzer unit having the anode section and the cathode section on the opposite both side surfaces, but may be a "single-pole type" electrolyzer unit having only the anode section and only the cathode section on the opposite both side surfaces. In this case, the electrolytic cell is configured by combining the electrolytic cell unit provided with only the anode section and the electrolytic cell unit provided with only the cathode section so as to be alternately arranged via the ion exchange membrane.

In the above description, the anode and/or the cathode have been described as having a conductive porous substrate, but a catalyst layer may be provided on the surface of such a substrate. The material constituting the catalyst layer is not particularly limited as long as it is a material that activates a desired electrolytic reaction. Although only an example, in the case of salt electrolysis, a catalyst layer containing a mixed oxide of a platinum group metal such as iridium, ruthenium, and/or platinum and a valve metal (more specifically, an iridium-tantalum mixed oxide, an iridium-ruthenium-titanium mixed oxide, an iridium-ruthenium-platinum mixed oxide, or the like) or the like may be provided on the conductive porous substrate (for example, an expanded alloy).

In addition, in the above description, the drawings in which the plurality of elastic parts 20 extend from both sides of the fixing part 10 in a pair manner are mainly used, but the present invention is not limited thereto. As shown in fig. 13 and 14, the conductive elastic body 100 of the present invention may have a mode in which a plurality of elastic portions 20 extend only from one side of the fixed portion 10. That is, as shown in fig. 13 and 14, the plurality of elastic portions 20 extending from the plurality of positions of the fixed portion 10 along the longitudinal direction may have the same extending direction (in short, the plurality of elastic portions may extend from the fixed portion in only one direction).

In the above description, the drawings in which the elastic portion 20 extends from the fixed portion 10 are mainly used, but the present invention is not limited thereto. One or more members extending from the fixing portion 10 may be considered as a conductive elastic body having a form in which the elastic portion 20 is not provided.

In the above description, the conductive members provided in the electrolytic cell of the present invention are characterized by the "alternately staggered wavy meandering arrangement", but the present invention is not limited thereto. The conductive elastic body provided in the electrolytic cell can exhibit the above-described "two-type spring characteristics" regardless of whether or not the conductive elastic body has the "configuration of alternately staggered undulations". That is, the electrolytic cell may be provided with a conductive elastic body 100 (see fig. 5 and 6), and at least one of the plurality of elastic portions 20 extending from the fixed portion 10 of the conductive elastic body 100 may be a double elastic portion exhibiting both a first elasticity provided as a local elastic characteristic and a second elasticity provided as a wide-range elastic characteristic.

The conductive member exhibiting the "two-spring characteristic" described above is not limited to the embodiment shown in fig. 5 and 6, and may be the embodiment shown in fig. 15 and 16. That is, the conductive elastic bodies may be arranged in a full alignment manner or not in the wavy curve of the plurality of double elastic portions. More specifically, as shown in fig. 5 and 6, the configuration of the wavy bends of the plurality of double elastic portions may not be all aligned along the longitudinal direction of the fixed portion, or as shown in fig. 15 and 16, the configuration of the wavy bends of the plurality of double elastic portions may be all aligned along the longitudinal direction of the fixed portion. In the embodiment of fig. 15 and 16, the crest portions and the trough portions caused by the wavy meandering of the bielastic portion 20 are aligned (preferably completely aligned) along the longitudinal direction of the fixing portion 10.

In addition, even in the case of a conductive body exhibiting "two-spring characteristics", a plurality of elastic portions 20 may be extended from only one side of the fixed portion 10. That is, even in the case of a conductive body exhibiting "two-type spring characteristics", as shown in fig. 17A, 17B, 18A, and 18B, the plurality of elastic portions 20 extending from the plurality of positions of the fixed portion 10 in the longitudinal direction may have the same extending direction (in short, the plurality of elastic portions may extend from the fixed portion in only one direction).

It should be confirmed that the present invention described above includes the following modes.

First mode: an electrically conductive elastomer for electrolytic cells, comprising:

the plurality of elastic parts are respectively bent in a wave shape,

Second mode: according to the conductive elastic body for an electrolytic cell of the first aspect, the elastic portions adjacent to each other are arranged such that the crest portions caused by the wavy curve are different from each other in separation distance from the fixing portion.

Third mode: according to the conductive elastic body for an electrolytic cell of the first or second aspect, the crest portions caused by the wavy bend are aligned every other elastic portion so as to extend along the longitudinal direction of the fixing portion.

Fourth mode: the conductive elastic body for an electrolytic cell according to any one of the first to third aspects, wherein the valley portions caused by the wavy bend are disposed at different distances from the fixing portion with respect to the elastic portions adjacent to each other.

Fifth mode: the conductive elastic body for an electrolytic cell according to any one of the first to fourth aspects, wherein trough portions caused by the wavy bend are aligned in every other elastic portion so as to extend along a longitudinal direction of the fixed portion.

Sixth mode: the conductive elastic body for an electrolytic cell according to any one of the first to fifth aspects, wherein in the elastic portions adjacent to each other, a peak portion of one of the elastic portions caused by the wavy bend and a valley portion of the other elastic portion caused by the wavy bend are located along the elastic portionThe long side directions of the fixing parts are adjacent to each other.

Seventh mode: the conductive elastic body for an electrolytic cell according to any one of the first to sixth aspects, wherein the plurality of elastic portions are paired so as to extend from a plurality of positions of the fixing portion in the longitudinal direction in opposite directions to each other.

Eighth mode: the conductive elastic body for an electrolytic cell according to the seventh aspect, wherein the conductive elastic body has a configuration in which the crest portions or the trough portions caused by the wavy meandering are arranged symmetrically about the fixing portion as an axial center in a plan view.

Ninth mode: the conductive elastic body for an electrolytic cell according to any one of the first to eighth aspects, wherein the fixing portion is provided with a mounting opening.

Tenth mode: the conductive elastomer for electrolytic cells according to any one of the first to ninth aspects, wherein the electrolytic cell is a zero-pole-pitch common salt electrolytic cell.

Eleventh mode for carrying out the invention: an electrolytic cell having an anode, a cathode, and an ion exchange membrane disposed between the anode and the cathode,

the conductive elastomer according to any one of the first to tenth aspects is provided on a back surface side of one of the anode and the cathode so that the one of the anode and the cathode is pressed toward the other of the anode and the cathode.

Twelfth mode: the electrolytic cell according to the eleventh aspect, wherein at least one of the anode and the cathode has a conductive porous base material.

Thirteenth mode for carrying out the invention: in the electrolytic cell according to the eleventh or twelfth aspect, one of the anode and the cathode is flexible relative to the other, and the other is rigid relative to the one.

Fourteenth mode for carrying out the invention: the electrolytic cell according to the twelfth or thirteenth aspect depending on the tenth aspect, wherein the electrolysis is performedThe tank is a zero-polar distance type salt electrolytic tank.

Fifteenth mode: an electrically conductive elastomer for electrolytic cells, comprising:

at least one of the plurality of elastic portions is a double elastic portion exhibiting both a first elasticity provided as a local elastic characteristic and a second elasticity provided as a wide-range elastic characteristic.

Sixteenth mode for carrying out the invention: the conductive elastic body for an electrolytic cell according to the fifteenth aspect of the present invention is characterized in that the first elasticity is based on a local shape of the double elastic portion, and the second elasticity is based on an overall extension form of the double elastic portion.

Seventeenth mode: the conductive elastic body for an electrolytic cell according to the fifteenth aspect or the sixteenth aspect, wherein the double elastic portion is bent in a wave-like manner and is provided so as to form an extending angle with respect to the main surface of the fixing portion as a whole.

Eighteenth mode: the conductive elastic body for an electrolytic cell according to the seventeenth aspect, wherein the first elasticity is elasticity caused by the undulation.

Nineteenth mode: the conductive elastic body for an electrolytic cell according to the seventeenth aspect or the eighteenth aspect, wherein the second elasticity is elasticity due to the extension angle.

Twentieth mode: the conductive elastic body for an electrolytic cell according to any one of the seventeenth aspect to the nineteenth aspect, wherein the bielastic portion is curved so as to form the extension angle with a boundary between the bielastic portion and the fixed portion as a starting point.

Twenty-first mode: the conductive elastomer for an electrolytic cell according to any one of the seventeenth to twentieth aspects, wherein the extension angle of the bielastic part is in a range of 1 ° to 45 °.

Twenty-second mode: the conductive elastomer for electrolytic cells according to any one of the seventeenth to twenty-first aspects, wherein at least two crest portions caused by the wavy bend are provided in the bielastic portion.

Twentieth mode: the conductive elastomer for electrolytic cells according to any one of the seventeenth to twenty-second aspects, wherein at least two valley portions caused by the wavy bend are provided in the double elastic portion.

Twenty fourth mode: the conductive elastic body for an electrolytic cell according to any one of the fifteenth aspect to the twenty-third aspect, wherein all of the plurality of elastic portions are curved in a wave-like manner.

Twenty-fifth mode: the conductive elastomer for electrolytic cells according to any one of the fifteenth to twenty-fourth aspects, wherein all of the extensions of the plurality of elastic sections form an extension angle with respect to the main surface of the fixed section.

Twenty-sixth mode: the conductive elastic body for an electrolytic cell according to any one of the fifteenth to twenty-fifth aspects, wherein the plurality of elastic sections are paired so as to extend from a plurality of positions of the fixing section in the longitudinal direction in opposite directions to each other.

Twenty-seventh mode: the conductive elastic body for an electrolytic cell according to a twenty-sixth aspect dependent on the twenty-fourteenth aspect, wherein the conductive elastic body has a configuration in which the crest portions or the trough portions caused by the wavy meandering are arranged symmetrically about the fixing portion as an axial center in a plan view.

Twenty eighth mode: the conductive elastic body for an electrolytic cell according to any one of the fifteenth to twenty-seventh aspects, wherein a mounting opening is provided in the fixing portion.

Twenty-ninth mode: the conductive elastomer for electrolytic cells according to any one of the fifteenth to twenty-eighth aspects, wherein the electrolytic cell is a zero-pole-pitch common salt electrolytic cell.

Thirtieth mode: an electrolytic cell having: an anode, a cathode, and an ion exchange membrane disposed between the anode and the cathode,

the conductive elastomer according to any one of the fifteenth to twenty-ninth aspects is provided on a back surface side of one of the anode and the cathode so that the one of the anode and the cathode is pressed toward the other of the anode and the cathode.

Thirty-first mode: the electrolytic cell according to the thirtieth aspect of the invention, wherein at least one of the anode and the cathode has a conductive porous base material.

Thirty-second mode: the electrolytic cell according to the thirty-first or thirty-first aspect, wherein the one of the anode and the cathode is flexible relative to the other, and the other is rigid relative to the one.

Thirty-third mode: the electrolytic cell according to any one of the thirtieth to thirty-second modes depending on the twenty-ninth mode, wherein the electrolytic cell is a zero-pole-pitch common salt electrolytic cell.

Examples

The invention was tested. Specifically, an experimental test was performed to confirm the difference between the electrolytic voltage (cell voltage corresponding to the voltage between electrodes) of the conductive elastomer of the "alternately staggered wavy meandering arrangement" and the electrolytic voltage (cell voltage corresponding to the voltage between electrodes) of the conductive elastomer other than this.

As example 1, salt electrolysis by an ion exchange membrane method of the zero-pole pitch method was performed under the following test conditions using the conductive elastomer of the present invention. That is, salt electrolysis was performed using a conductive elastomer having a "wavy curve arrangement with alternate shifts".

Example 1

Conductive elastomer: conductive elastic body of "alternately staggered wavy meandering arrangement" shown in fig. 2

Anode: rigid anode of expansion alloy (model MD-50NS)

Cathode: flexible cathode of plain weave grid (model MDC-60, 30 mesh, aperture ratio 67.7%)

Cell voltage: for comparison of the electrode voltages, 4kA/m was used²Voltage converted by 32% NaOH at 90 deg.C

Ion exchange membranes: cation exchange membrane (model F8080A)

Comparative example 1

Salt electrolysis by an ion exchange membrane method of the zero-pole pitch method was performed in the same manner as in example 1, except that the conductive elastomer shown in fig. 19 was used as the conductive elastomer. That is, as comparative example 1, salt electrolysis was performed using a conductive elastomer having no "alternately staggered wavy meandering arrangement".

The results are shown in fig. 20. As is clear from the graph of fig. 20, the electrolytic voltage can be reduced by using the conductive elastic body of the "alternately staggered wavy meandering arrangement". That is, it is found that if the conductive elastomer of the present invention is used, more efficient electrolysis operation can be performed (although the result shown in fig. 20 is a voltage drop of a few points or less, the scale of salt electrolysis by the zero-pole-pitch ion exchange membrane method is particularly large, and even such a voltage drop is significant for the reduction of power consumption associated with the voltage drop of the entire electrolytic cell).

Industrial applicability

The conductive elastomer of the present invention can be used in various electrolytic cells. In particular, the reaction force provided by the conductive elastomer contributes to the close contact of the anode, the separator, and the cathode with each other, and therefore the conductive elastomer of the present invention can be more suitably used for a zero-pole-pitch type electrolytic cell.

Cross reference to related applications

The present application claims Paris convention priority based on Japanese patent application No. 2018 & 141710 (application No. 2018 & 7/27 & 2018, title of the invention: "conductive elastomer for electrolytic cell and electrolytic cell") and Japanese patent application No. 2018 & 141715 (application No. 2018 & 7/27 & 2018, title of the invention: "conductive elastomer for electrolytic cell and electrolytic cell"). The disclosure of the above application is incorporated herein by reference in its entirety.

Description of the reference numerals

10-a fixed part; 20-elastic/bielastic; 40-mounting openings; 50-a fixing member; 100-conductive elastomer; 200-an electrolyzer unit; 200' -an electrolyzer unit; 200' -cell unit; 230-the anode face of the cell unit; 235-a rigid anode; 200A-one of the opposing side faces of the cell unit; 200B-the other of the two opposing sides of the cell unit; 230' -the anode face of the cell unit; 260-cathode side of cell unit; 260 "-cathode side of cell unit; 265-flexible cathode; 268-a cathode base; 300-ion exchange membrane.

Claims

1. An electrically conductive elastomer for electrolytic cells, comprising:

the plurality of elastic parts are respectively bent in a wave shape,

2. The conductive elastomer for electrolytic cell according to claim 1,

with respect to the elastic portions adjacent to each other, the crest portions caused by the wavy bend are arranged so that the separation distances from the fixing portions are different from each other.

3. The conductive elastomer for electrolytic cell according to claim 1 or 2,

the crest portions caused by the wavy curve are aligned in every other elastic portion along the longitudinal direction of the fixing portion.

4. The conductive elastomer for electrolytic cell according to any one of claims 1 to 3,

with respect to the elastic portions adjacent to each other, valley portions caused by the wavy bend are arranged so as to be different from each other in separation distance from the fixing portion.

5. The conductive elastomer for electrolytic cell according to any one of claims 1 to 4,

valley portions caused by the wavy bend are aligned every other one of the elastic portions so as to be along the longitudinal direction of the fixing portion.

6. The conductive elastomer for electrolytic cell according to any one of claims 1 to 5,

in the elastic portions adjacent to each other, a crest portion of one of the elastic portions caused by the undulation and a trough portion of the other elastic portion caused by the undulation are adjacent to each other in the longitudinal direction of the fixing portion.

7. The conductive elastomer for electrolytic cell according to claim 1,

8. The conductive elastomer for electrolytic cell according to claim 7,

the first elasticity is based on a local shape of the dual-elastic portion, and the second elasticity is based on an overall extension of the dual-elastic portion.

9. The conductive elastomer for electrolytic cell according to claim 7 or 8,

the double elastic portion is provided so as to form an extension angle with respect to a main surface of the fixing portion as a whole.

10. The conductive elastomer for electrolytic cell according to claim 9,

the double elastic portion is bent such that the extension angle is formed with a boundary between the double elastic portion and the fixing portion as a starting point.

11. The conductive elastomer for electrolytic cell according to claim 9 or 10,

the extension angle of the double elastic part is in the range of 1-45 degrees.

12. The conductive elastomer for electrolytic cell according to any one of claims 9 to 11,

the second elasticity is elasticity caused by the extension angle.

13. The conductive elastomer for electrolytic cell according to any one of claims 7 to 12,

the first elasticity is elasticity caused by the wavy bend.

14. The conductive elastomer for electrolytic cell according to any one of claims 7 to 13,

in the double elastic portion, at least two peaks caused by the wavy bend are provided.

15. The conductive elastomer for electrolytic cell according to any one of claims 7 to 14,

in the double spring portion, at least two valleys caused by the wavy bend are provided.

16. The conductive elastomer for electrolytic cell according to any one of claims 7 to 15,

all of the extensions of the plurality of elastic portions form an extension angle with respect to a main surface of the fixed portion.

17. The conductive elastomer for electrolytic cell according to any one of claims 1 to 16,

the plurality of elastic portions are paired so as to extend from a plurality of positions of the fixing portion in the longitudinal direction in opposite directions to each other.

18. The conductive elastomer for electrolytic cell as claimed in claim 17,

in the conductive elastic body, the arrangement of the crest portions or the trough portions caused by the wavy meandering is symmetrical with the fixing portion as an axial center in a plan view.

19. The conductive elastomer for electrolytic cell according to any one of claims 1 to 18,

the fixing part is provided with an installation opening.

20. The conductive elastomer for electrolytic cell according to any one of claims 1 to 19,

the electrolytic bath is a zero-polar distance type salt electrolytic bath.

21. An electrolytic cell, characterized in that,

comprises an anode, a cathode, and an ion exchange membrane disposed between the anode and the cathode,

the conductive elastomer according to any one of claims 1 to 20 is provided on the back surface side of one of the anode and the cathode so that the one of the anode and the cathode is pressed toward the other of the anode and the cathode.

22. The electrolytic cell of claim 21,

at least one of the anode and the cathode has a conductive porous substrate.

23. The electrolytic cell of claim 21 or 22,

one of the anode and the cathode is flexible relative to the other, and the other is rigid relative to the one.

24. The electrolytic cell according to any one of claims 21 to 23 depending on claim 20,

is a zero polar distance type salt electrolytic bath.