WO2012091055A1

WO2012091055A1 - Ion-exchange membrane method electrolytic cell

Info

Publication number: WO2012091055A1
Application number: PCT/JP2011/080305
Authority: WO
Inventors: 健二坂本; 幹治吉光; 岡本　光正
Original assignee: 東ソー株式会社; クロリンエンジニアズ株式会社
Priority date: 2010-12-28
Filing date: 2011-12-27
Publication date: 2012-07-05
Also published as: JP5653209B2; JP2012140652A

Abstract

An ion-exchange membrane method electrolytic cell in which an electrode support member therefor is: configured from a corrosion-resistant frame (A) having at least a section thereof covered by an elastic mat, and a corrosion-resistant frame (B) having no section thereof covered by the elastic mat; and supported and housed between a flexible electrode and a current collector. Preferably, the flexible electrode and the electrode support member are fixed to the current collector by a pin that passes through the flexible negative electrode but does not pass through the space having the elastic mat of the electrode support member. This ion-exchange membrane method electrolytic cell can be produced easily, and can be operated stably over the long term without the ion-exchange membrane being damaged.

Description

Ion exchange membrane electrolytic cell

The present invention relates to an ion exchange membrane method electrolytic cell used in the electrolytic industry represented by chloralkali electrolysis.

The ion exchange membrane electrolytic cell of the present invention is a zero-gap electrolytic cell developed for the purpose of reducing the required energy with the distance between the anode and the cathode shortened as much as possible. It has the feature that electrolytic operation can be performed stably for a long time without damaging the membrane.

The ion exchange membrane electrolysis industry represented by chloralkali electrolysis plays an important role as a material industry, but the ion exchange membrane electrolysis cell consumes a large amount of electric energy. For this reason, energy saving in the ion exchange membrane electrolytic industry is regarded as a universal issue, and various research and development are being carried out continuously.

Electroelectric energy consumed during electrolysis is proportional to the electrolysis voltage, so reducing electrolysis voltage directly leads to energy savings. For the purpose of reducing the electrolysis voltage, research and development of a so-called zero gap electrolyzer in which the distance between the anode and the cathode is made as short as possible has been performed. The zero-gap electrolytic cell has a structure in which an ion exchange membrane is sandwiched between an anode and a cathode, and can reduce the electrical resistance of the electrolytic solution as much as possible, greatly contributing to energy saving of chloralkali electrolysis.

FIG. 1 shows an example of a cross-sectional structure of a zero gap electrolytic cell. The zero gap electrolytic cell has a structure in which the anode chamber (1) and the cathode chamber (2) are partitioned by the ion exchange membrane (3), and the ion exchange membrane (3) is sandwiched between the anode (4) and the cathode (5). Have. In the zero gap electrolytic cell, the ion exchange membrane (3) is made of a thin resin film of 1 mm or less, and the ion exchange membrane (3) is damaged when the anode (4) and / or the cathode (5) is excessively pressed. The technique of pressing the anode (4) and / or the cathode (5) uniformly against the ion exchange membrane with an appropriate pressure is important.

For this reason, “a relatively rigid mesh screen used as one electrode provided on the surface of the ion exchange membrane, and flexibility used as the other electrode provided on the other surface of the ion exchange membrane. Alternatively, an ion exchange membrane electrolytic cell composed of a thin flexible screen and an elastic mat (elastic compressible mat) provided on the outer surface of the thin screen has been proposed (for example, see Patent Document 1). ). This proposed ion exchange membrane method electrolytic cell has a structure in which a flexible electrode is pressed against the ion exchange membrane by the elastic repulsive force of the elastic mat, and the ion exchange membrane is sandwiched between the other rigid electrode. It is a zero gap electrolytic cell having.

In the zero gap electrolytic cell described in Patent Document 1, for example, the electrode support member (6) installed on the back surface of the flexible cathode (5) in FIG. 1 is made of an elastic mat, and the elastic repulsive force of the elastic mat is used. The flexible cathode (5) has a structure that is pressed against the ion exchange membrane (3) toward the rigid anode (4). A current collector (7) is installed outside the electrode support member (6).

In the zero gap electrolytic cell described in Patent Document 1, it is possible to uniformly press the anode (4) and / or the cathode (5) against the ion exchange membrane (3) with an appropriate pressure. Even an industrial-size zero-gap electrolytic cell having

Thereafter, the performance of the zero gap electrolytic cell was widely improved, and “a flexible or thin electrode having a thickness of 0.3 mm or less and the area of one hole being 0.05 to 1.0 mm. ² and a zero-gap electrolytic cell using a porous body having an aperture ratio of 20% or more and an elastic mat made of an assembly of wires having a diameter of 0.1 to 1 mm is proposed (for example, , See Patent Document 2).

In addition, a “zero gap electrolyzer using an elastic cushion material formed by winding a metal coil body around a corrosion resistant frame as an electrode support member” has been proposed (for example, see Patent Document 3). This proposed zero gap electrolytic cell has a structure in which an elastic mat composed of a metal coil body is fixed in a space formed by a corrosion-resistant frame, and the elastic mat is easy to handle and can be reused. It has the feature of being. The electrode support member described in Patent Document 3 is illustrated in FIGS. 9 and 10 (showing a cross section a in FIG. 9).

Furthermore, “zero gap electrolysis in which the flexible electrode and the elastic mat are fixed with pins that penetrate the flexible electrode and the elastic mat and engage with the holes of the porous collector plate installed on the back surface of the elastic mat. A “tank” has been proposed (see, for example, Patent Document 4). For example, as shown in FIG. 2 and FIG. 3 showing a cross section at b, the fixing means described in Patent Document 4 includes a fixing pin (8) made of a flexible cathode (5) and a metal. The flexible mat (5) and the metal coil body (10) are fixed to the current collector plate (7) through the elastic mat made of the coil body (10) and engaged with the holes of the current collector plate (7). Configured to be.

In this structure, during the manufacturing process, when the pin (8) is engaged with the hole of the current collector plate (7), the pin (8) is connected to the current collector plate (10) while compressing the metallic coil body (10). 7) It is necessary to push in toward the side. When excessive force is applied to the pin (8), the pin (8) is deformed, or the flexible cathode (5) made of a thin porous body of 0.3 mm or less is excessively deformed or damaged. was there.

Also, when assembling a zero gap electrolytic cell, the flexible cathode (5) contacts the ion exchange membrane (3) and is pushed to the anode (4) side. At this time, since the anode (4) is rigid, the ion exchange membrane (3) does not move, the distance between the flexible cathode (5) and the current collector (7) is reduced, and the metal coil body (10) is compressed. As a result, the flexible cathode (5) is brought into close contact with the ion exchange membrane (3) by the elastic repulsion of the metal coil body (10), so that the distance between the anode (4) and the flexible cathode (5) is possible. Become shorter.

In the zero gap electrolytic cell described in Patent Document 4, a recess is formed in the flexible cathode (5) in contact with the pin (8) as shown in FIG. In such a configuration, when the flexible cathode (5) pushed by the ion exchange membrane (3) during the assembly of the electrolytic cell moves toward the current collector (7), the flexibility near the pin (8). The cathode (5) does not move. Therefore, as shown in FIG. 4, the flexible cathode (5) in the vicinity of the pin is deformed, and the deformed portion (11) of the flexible cathode (5) projects locally to the ion exchange membrane (3) side. Inconvenience occurred.

As a result, the cathode deformation part (11) in the vicinity of the pin (8) rubs against the ion exchange membrane (3) during operation, and the ion exchange membrane is easily damaged. As described above, there is a problem that the ion exchange membrane is easily damaged during the assembly and operation of the electrolytic cell.

Japanese Patent Publication No. 63-53272 JP 59-173281 A Japanese Patent No. 3860132 JP 2000-178781 A

As described above, the zero gap electrolytic cell of the prior art is difficult to fix the elastic mat and the flexible cathode at the time of assembly, and the ion exchange membrane is easily damaged during the assembly of the electrolytic cell and during operation. have.

An object of the present invention is to provide a zero-gap electrolytic cell that is easy to manufacture and does not have a deformed cathode part that causes damage to the ion exchange membrane.

The present invention is an ion exchange membrane electrolytic cell having a configuration in which an electrode support member is sandwiched and accommodated between a flexible electrode and a current collector plate, and at least a part of the electrode support member is elastic. There is provided an ion exchange membrane method electrolytic cell comprising a corrosion resistant frame (A) covered with a mat and a corrosion resistant frame (B) not covered with an elastic mat at all.

In the ion exchange membrane electrolytic cell provided by the present invention, the work of fixing the elastic mat and the flexible cathode, which has been difficult in the conventional zero gap electrolytic cell, is extremely simple. In addition, since there is no deformation of the cathode that causes damage to the ion exchange membrane, there is a special effect that enables stable operation over a long period of time. Moreover, electrode replacement when electrode performance deteriorates can be performed very easily.

It is sectional drawing which showed the zero gap electrolytic cell. It is the top view which showed the conventional cathode attachment state. It is an expanded sectional view of the b section of FIG. It is an expanded sectional view of the b section of Drawing 2 at the time of electrolytic cell use. It is the top view which showed an example of the electrode support member used for the electrolytic cell of this invention. FIG. 6 is a sectional view taken along line aa in FIG. 5.

It is the top view which showed an example of the cathode attachment state in the electrolytic cell of this invention. It is an expanded sectional view of the b section of FIG. It is the top view which showed the conventional elastic member. FIG. 10 is a sectional view taken along line aa in FIG. 9. It is an expanded sectional view of the b section of Drawing 7 at the time of electrolytic cell use.

It is the top view which showed another example of the electrode supporting member used for the electrolytic cell of this invention. It is the figure which showed an example of the pin used for the electrolytic cell of this invention. It is sectional drawing which showed another example of the pin used for the electrolytic cell of this invention. It is the figure which showed another example of the pin used for the electrolytic cell of this invention. It is a figure which shows the relative positional relationship of the hole of a current collecting plate, and the front-end | tip part of a pin. It is a figure which shows the relative positional relationship of the hole of a current collecting plate, and the front-end | tip part of a pin.

DESCRIPTION OF SYMBOLS 1 Anode chamber 2 Cathode chamber 3 Ion exchange membrane 4 Rigid anode or anode 5 Flexible cathode or cathode 6 Electrode support member 7 Current collecting plate 8 Pin 9 Corrosion resistant frame (A)
DESCRIPTION OF SYMBOLS 10 Metal coil body 11 Cathode deformation part 12 Frame connection material 13 Corrosion resistance frame (B)
14 Pin head 15 Pin tip 16 Pin rod 17 Pin head cut 18 Current collector hole

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.
In the following description, the rigid anode (4) and the flexible cathode (5) will be described. However, embodiments in which the polarities of the electrodes are reversed, that is, the rigid cathode (4) and the flexible anode (5) are used. The aspect used as the scope of the present invention is also within the scope of the present invention, and in the claims, both aspects are expressed as flexible electrodes.

Moreover, although the case where it uses for salt electrolysis as an application example of the ion exchange membrane method electrolytic cell of this invention is demonstrated, it can utilize suitably also for potassium chloride aqueous solution electrolysis, alkaline water electrolysis, etc. other than salt electrolysis.

The ion exchange membrane electrolytic cell of the present invention is a so-called zero gap electrolytic cell in which the distance between the anode and the cathode is made as short as possible, and its cross-sectional structure is shown in FIG. The anode chamber (1) and the cathode chamber (2) are partitioned by an ion exchange membrane (3), and the electrode support member (6) is sandwiched between the flexible cathode (5) and the current collector plate (7). Are housed in different forms.

The rigid anode (4) is not particularly limited, and a conventionally known one may be used in a timely manner. For example, a chlorine generating electrode in which an expanded metal made of titanium carries a chlorine generating electrode catalyst such as iridium oxide and / or ruthenium oxide is widely known.

The ion exchange membrane (3) is not particularly limited, and a conventionally known one may be used in a timely manner. For example, an ion exchange membrane made of a fluororesin film having a cation exchange group such as a sulfonic acid group or a carboxylic acid group is widely known.

The flexible cathode (5) may be soft. As the flexible cathode (5) for salt electrolysis, a hydrogen generating electrode that generates hydrogen during electrolysis and an oxygen gas diffusion electrode that reduces oxygen gas are widely known, and any of them is preferably used. In particular, a hydrogen generating cathode that generates hydrogen during electrolysis is preferable.
As the hydrogen generating cathode, a so-called active cathode in which a hydrogen generating electrode catalyst is supported on a nickel base is usually applied. Currently, various active cathodes have been developed and put to practical use, and any of these active cathodes can be used in the present invention.

There is no particular limitation on the nickel base used for the active cathode, but a porous plate such as nickel expanded metal is common. The thickness of the nickel substrate is preferably 1 mm or less, more preferably 0.3 mm or less. If the nickel base is too thick, the flexibility is insufficient, a uniform zero gap cannot be secured, and the energy saving effect of the present invention may not be obtained. In some cases, the ion exchange membrane is excessively pressed and damaged. Arise. On the contrary, the lower limit of the thickness of the nickel base material is not particularly limited as long as the nickel base material can be handled, but is usually 0.01 mm or more.

The hydrogen generation catalyst supported on the nickel base of the active cathode is not particularly limited, but a noble metal catalyst such as platinum, a platinum alloy, or ruthenium oxide is preferable. By using a noble metal catalyst, the hydrogen overvoltage can be kept low over a long period of time with a small amount of catalyst, so that the stable operation period of the electrolytic cell can be further extended.

As the current collector plate (7), a conductive metal plate having excellent corrosion resistance is used. For example, a nickel or stainless steel plate is preferably used. In addition, a metal plate with excellent conductivity, such as copper, having a surface coated with nickel and having improved corrosion resistance is also preferably used.

The thickness of the current collector plate (7) is not particularly limited, but is preferably 1 to 3 mm. If it is less than 1 mm, the rigidity is insufficient and the effects of the present invention may not be obtained. On the other hand, if it is too thick, the material cost is deteriorated.

In FIG. 3 showing the conventional cathode mounting state, the current collector plate (7) has a hole that engages with the pin (8). A hole may be provided only at a position where the pin (8) is installed, or the current collector plate (7) may be a perforated plate, and the pin (8) may be engaged with a part of the holes. The pin (8) extends from the flexible cathode (5) through the electrode support member (6) (consisting of the metal coil body (10) and the corrosion-resistant frame (9) A) and the current collector plate (7). The flexible cathode (5) and the electrode support member (6) are fixed to the current collector plate (7) by pins (8). Usually, the current collector plate (7) is composed of a perforated plate and engages with the pin (8), and the ion exchange membrane (3) and the flexible cathode (5) and the back surface of the current collector plate (7). Ensure that the electrolyte and gas can flow smoothly between the parts.

In the ion exchange membrane electrolytic cell of the present invention, an electrode support member (6) is installed between the flexible cathode (5) and the current collector plate (7). The electrode support member (6) has at least a part of its surface covered with an elastic mat.

The form of the electrode support member (6) used in the present invention is exemplified in FIG. 5 and FIG. 6 showing a cross-sectional view taken along the line aa in FIG. A metal coil body (10) is preferably wound around a part of the corrosion resistant frame (A) (9) to form an elastic mat. At least a part of the surface of the electrode support member (6) is covered with an elastic mat.

The electrode support member (6) attached to the ion exchange membrane electrolytic cell of the present invention illustrated in FIG. 5 is composed of four corrosion resistant frames (A) (9) and four surrounding the corrosion resistant frame (A). It consists of a corrosion-resistant frame (B) (13) and two frame connecting members (12) that connect the corrosion-resistant frame (A) and the corrosion-resistant frame (B). The outer periphery of the electrode support member (6) is composed of a corrosion-resistant frame (B) (13), and the two corrosion-resistant frames (B) (13) in the lateral direction are bridged by two frame connecting materials (12). The frame connecting portions (12) are bridged by two or more corrosion resistant frames (A) (9). At least a part of the surface of the frame connecting portion (12) and the surface of the corrosion-resistant frame (A) (9) is covered with an elastic mat, preferably made of a metal coil body (10).

The corrosion resistant frame (A) (9) is made of a material that is corrosion resistant to the electrolyte, and is usually made of nickel or stainless steel round bars or square bars. For example, it is manufactured by combining nickel round bars having a diameter of 1 to 3 mm. Moreover, the thing which coat | covered the surface of the metal excellent in electroconductivity, such as copper, with nickel, and improved corrosion resistance is used suitably.

The metal coil body (10) is a metal having a coil shape, and for example, a spiral metal coil body (10) obtained by rolling a metal wire is applied. As the wire to be used, a material having high corrosion resistance such as nickel or stainless steel is preferably used, and a metal wire excellent in conductivity such as copper having a surface coated with nickel is preferably used. A spiral metal coil body (10) obtained by rolling a copper wire may be coated with nickel to improve corrosion resistance.

The coil winding diameter (apparent diameter of the coil) of the metal coil body (10) is not particularly limited, but is usually 3 to 10 mm. If the coil winding diameter is smaller than 3 mm, the compressible thickness of the elastic mat is insufficient, and the effects of the present invention may not be exhibited. On the other hand, if it is larger than 10 mm, the handleability may be deteriorated, and the elastic repulsion may be insufficient due to plastic deformation during compression.

The coil thickness of the metal coil body (10) is not particularly limited, but is usually 0.005 to 1 mm, preferably 0.01 to 0.1 mm. If the coil is thicker than 1 mm, the elastic repulsion force during compression becomes abnormally strong, and the effects of the present invention may not be obtained. Conversely, if it is thinner than 0.005 mm, the coil may be damaged during handling.

The metal coil body (10) is wound around the corrosion resistant frame (A) (9) to form an elastic mat. As shown in FIG. 5 and FIG. 6 showing the aa cross section thereof, an elastic mat is formed by winding the metal coil body (10) around a corrosion-resistant frame (A) (9) combined in a rectangular shape. Can do. As another aspect, the metal coil body (10) may be wound around the corrosion-resistant frame (A) in which only two are arranged in parallel. When the metal coil body (10) is wound around the corrosion resistant frame (A) (9), taking FIG. 5 as an example, the four of the four frames constituting the rectangular corrosion resistant frame (A) (9) The at least one metal coil body (10) may be wound so as to obtain a substantially uniform density between the two facing each other.

The amount of the metal coil body (10) wound around the corrosion-resistant frame (A) (9) is appropriately adjusted so that the elastic repulsion force of the elastic mat becomes a desired value. The amount of winding differs depending on the winding diameter, thickness and material of the coil. In general, the elastic repulsion force may be 10 to 150 g per square centimeter when the elastic mat is compressed to 60 to 80% of the thickness at the time of non-compression.

The above is one of the preferred embodiments of the configuration of the space portion having the elastic mat of the electrode support member (6) of the present invention. Next, the example of preferable embodiment of the structure of the space part which does not have an elastic mat of the electrode support member (6) of this invention is demonstrated.

As shown in FIG. 5, the corrosion-resistant frame (A) (9) around which the metal coil body (10) is wound is connected to the corrosion-resistant frame (B) (13) via the frame connecting material (12). Has been. FIG. 5 shows an example in which the corrosion-resistant frame (B) (13) surrounds the entire periphery of the rectangular corrosion-resistant frame (A) (9), but the corrosion-resistant frame (B) (13) is the corrosion-resistant frame (A) ( Even if it encloses a part of 9), the effects of the present invention can be obtained.

The requirements as the constituent material of the corrosion resistant frame (B) (13) and the frame connecting material (12) are the same as those of the corrosion resistant frame (A) (9). That is, the corrosion-resistant frame (B) (13) and the frame connecting material (12) are made of a material that is corrosion-resistant to the electrolytic solution, and are usually manufactured with nickel or stainless steel round bars or square bars. For example, a nickel round bar having a diameter of 1 to 3 mm can be preferably applied, and a metal with excellent conductivity, such as copper, coated with nickel is preferably used.

The corrosion-resistant frame (A) (9), the corrosion-resistant frame (B) (13), and the frame connecting material (12) do not have to be made of the same material, but usually they are round bars and square bars made of the same material. Consists of.
The method for connecting the frame connecting material (12) to the corrosion resistant frame (A) (9) and / or the corrosion resistant frame (B) (13) is not particularly limited, and may be connected by welding or screwing.

The elastic mat does not exist in at least a part of the space formed by the corrosion resistant frame (A) (9) and the corrosion resistant frame (B) (13), and a space without the elastic mat is formed. Therefore, the electrode support member (6) shown in FIG. 5 is one of the preferred embodiments of the present invention having both a space having an elastic mat and a space not having an elastic mat.

Another preferred embodiment of the electrode support member (6) of the present invention is illustrated in FIG.
In the embodiment shown in FIG. 12, a metal coil body (10) is wound around each of two corrosion-resistant frames (A) and (9), and these are connected to each other by a frame connecting material (12). (A) Corrosion-resistant frames (B) and (13) surrounding (9) are connected to the corrosion-resistant frames (A) and (9) by a frame connecting agent (12). The metal coil body (10) is not wound around the corrosion resistant frame (B) (13).

As described above, a plurality of corrosion-resistant frames (A) and (9) are connected by the connecting member (12), and the corrosion-resistant frames (B) and (13) are connected to a part of the periphery by the connecting member (12). It is possible to constitute the electrode support member (6) having both the space having the elastic mat of the present invention and the space not having the elastic mat.

In the ion exchange membrane electrolytic cell of the present invention, the electrode support member (6) is sandwiched between the flexible cathode (5) and the current collector plate (7). There is no particular limitation on the mode in which the electrode support member (6) is sandwiched between the flexible cathode (5) and the current collector plate (7). However, if the position of the flexible cathode (5) or the electrode support member (6) is shifted during the assembly of the electrolytic cell or during the operation of the electrolytic cell, the ion exchange membrane (3) may be damaged or the voltage may be increased. In some cases, the flexible cathode (5) and the electrode support member (6) are preferably fixed to the ion exchange membrane electrolytic cell.

Next, a preferred embodiment for fixing the flexible cathode (5) and the electrode support member (6) in the ion exchange membrane electrolytic cell of the present invention to the ion exchange membrane electrolytic cell will be described.
In the ion exchange membrane method electrolytic cell of the present invention, the current collector plate (7) is fixed to the electrolytic cell by welding or the like. The flexible cathode (5) and the electrode support member (6) are fixed to the current collector plate (7) by fixing the flexible cathode (5) and the electrode support member (6) to the ion exchange membrane method electrolytic cell. Fix it. For example, the flexible cathode (5) and the electrode support member (6) are connected to the current collector plate by a pin (8) passing through the flexible cathode (5), the electrode support member (6) and the current collector plate (7). It is fixed to (7). The pin (8) is configured so as to penetrate the flexible cathode (5) but not penetrate the space having the elastic mat of the electrode support member (6).

FIG. 7 and FIG. 8 showing a cross section of FIG. 7 show a flexible cathode (5), an electrode support member (6) [corrosion resistant frame (A) (9), corrosion resistant frame (B) (13) and metal. A preferred embodiment of fixing a coil body (10)] to a current collector plate (7) is illustrated. The pin (8) is only the space portion without the elastic mat of the electrode support member (6), and penetrates the flexible cathode (5), the electrode support member (6), and the current collector plate (7). The flexible cathode (5) and the electrode support member (6) are fixed to the current collector plate (7).

For example, as shown in FIG. 7, the space portion having no elastic mat between the corrosion-resistant frame (B) (13) and the connecting member (12), and the corrosion-resistant frame (B) (13) and the corrosion resistance. A pin (8) passes through a space portion that does not have an elastic mat between the frames (A) and (9), and an electrode support member (6) and a flexible cathode (5) serve as a current collector plate (7). It is fixed to.

Any pin may be used as long as it has corrosion resistance and can be fixed through the flexible cathode (5), the electrode support member (6), and the current collector plate (7). The material is preferably a corrosion-resistant material such as nickel, stainless steel or fluororesin. However, it is more preferable to use a fluororesin pin (8) because the possibility of damaging the flexible cathode (5) and the ion exchange membrane (3) is low.

FIG. 13 shows an example of a suitable pin (8) used in the present invention. The pin (8) has a shape in which a head (14) made of a circular or polygonal thin plate and a tip (15) are connected by a rod-like member (16). The tip portion (15) has a shape that engages with the hole (18) of the current collector plate (7). The tip portion (15) is inserted from the flexible cathode (5) side, and the flexible cathode (5) ), The electrode support member (6), and the current collector plate (7) are passed through to fix the flexible cathode (5) and the electrode support member (6) to the current collector plate (7).

In the present invention, the “shape that engages with the hole” refers to a shape that can be inserted into the hole and that cannot be pulled out naturally after insertion, but can be pulled out artificially. FIG. 14 shows a cross-sectional view of the pin (8) of FIG. The tip (15) of the pin has a notch (17), and the notch (17) is open in the natural state, and the size of the pin tip (15) is the size of the current collector (not shown) (7). Although slightly larger than the inner diameter of the hole, the inner diameter of the hole of the current collector plate (not shown) (7) becomes smaller when the notch (17) is reduced. Accordingly, the slit (17) can be easily inserted into the concavity when inserted into the hole, but the slit (17) returns to its original state after insertion and does not come out of the hole naturally. However, when a large force is applied by human power or the like, the cut (17) is narrowed and can be pulled out from the hole.

FIG. 15 illustrates another preferred pin (8) configuration, and the pin tip (15) has a prismatic shape. On the other hand, the current collector plate (7) is composed of, for example, a perforated plate having a large number of rhombus-shaped holes typified by expanded metal. By positioning the tip (15) of the pin (8) and the hole (18) of the current collector plate (7) in the relative relationship shown in FIG. 16, the tip (15) can be easily inserted into the hole (18). Or it can be extracted. On the other hand, after the tip (15) of the pin (8) is inserted into the hole (18) of the current collector (7), the pin (8) is rotated by about 90 ° and positioned in the relative relationship shown in FIG. ) Does not fall out of the current collector plate (7).

Although one example of the preferred embodiment of the tip (15) of the pin (8) that engages with the hole (18) of the current collector plate (7) has been described above, the tip ( 15) can be inserted into the hole (18) of the current collector plate (7) and does not fall off naturally after insertion, but can be pulled out artificially, the effect of the present invention. It goes without saying that is obtained.

The electrode support member (6) used in the present invention has a novel shape having both a space having an elastic mat and a space portion not having an elastic mat, and has an elastic mat of the electrode support member (6). By fixing at least a part of the empty space to the current collector (7), the electrode support member (6) can be fixed to the ion exchange membrane electrolytic cell. For example, the flexible cathode (5) and the electrode support member (6) are connected to the current collector plate by a pin (8) passing through the flexible cathode (5), the electrode support member (6) and the current collector plate (7). It is fixed to (7). Thus, it is possible to form a structure in which the pin (8) penetrates the flexible cathode (5) but does not penetrate the space portion having the elastic mat of the electrode support member (6).

In this case, as shown in the cross-sectional structures in FIGS. 8 and 11, the repulsive force received by the pin (8) is insignificant in any of the mounting operation of the pin (8), the electrolytic cell assembly operation, and the electrolysis. The pin (8) is deformed during the operation of engaging the pin (8) with the hole of the current collector plate (7), or the flexible cathode (5) is excessively deformed or damaged. There is nothing.

In addition, when the electrolytic cell is assembled, the flexible cathode (5) is pushed by the ion exchange membrane (3) and moves toward the current collector plate (7). At this time, the flexible cathode (5) of the elastic mat portion is used. ) And the flexible cathode (5) around the pin (8) have the same moving distance, and the cathode deformed portion (11) as shown in FIG. 4 does not occur. Therefore, the ion exchange membrane is not damaged when the electrolytic cell is assembled or during operation.
It goes without saying that an oxygen gas diffusion electrode can be used as the cathode instead of the hydrogen generating cathode.

The conventional electrode support member (6) illustrated in FIGS. 9 and 10 does not have the “corrosion resistant frame (B) not covered with an elastic mat” as used in the present invention. Therefore, when the pin (8) is attached at a position where the flexible cathode (5) penetrates but the space portion having the elastic mat of the electrode support member does not penetrate, the flexible cathode (7) is attached to the current collector plate (7). 5) can be fixed, but the electrode support member (6) cannot be fixed, and the effect of the present invention cannot be obtained. In order to attach the electrode support member (6) without the corrosion-resistant frame (B) which is not covered with the elastic mat at all, it is essential to penetrate the elastic mat with the pin (8). As described above, the ion exchange membrane is easily damaged during the assembly of the electrolytic cell and during the electrolysis operation.

The ion exchange membrane method salt electrolytic cell of the present invention overcomes the problems of the conventional zero gap electrolytic cell and exhibits the energy saving performance possessed by the zero gap electrolytic cell. That is, the energy required for electrolysis in the electrolytic industry can be kept low, and stable operation can be performed for a long time.

Taking advantage of the above features, the ion exchange membrane electrolytic cell of the present invention is advantageously employed in the electrolytic industry represented by chloralkali electrolysis such as salt electrolysis. It can also be applied to aqueous potassium chloride electrolysis and alkaline water electrolysis.

Claims

An ion exchange membrane electrolytic cell having a configuration in which an electrode support member is sandwiched and accommodated between a flexible electrode and a current collector plate, and the electrode support member is at least partially covered with an elastic mat. An ion-exchange membrane electrolytic cell characterized in that it is composed of a corrosion-resistant frame (A) and a corrosion-resistant frame (B) not covered with an elastic mat at all.
The flexible electrode and the electrode support member are fixed to the current collector plate with a pin, and the pin has a structure in which the flexible cathode penetrates but the space portion having the elastic mat of the electrode support member does not penetrate. The ion exchange membrane method electrolytic cell according to claim 1.
The ion exchange membrane method electrolytic cell according to claim 1 or 2, wherein the elastic mat comprises a metal coil body.
Holes are provided in the flexible electrode and the current collector plate, and the flexible electrode and the electrode support member are formed on the current collector plate by a pin that passes through the hole and the space that does not have the elastic mat of the electrode support member. The ion exchange membrane method electrolytic cell according to any one of claims 1 to 3, wherein the electrolytic cell is fixed.
The ion exchange membrane method electrolytic cell according to any one of claims 1 to 4, wherein the flexible electrode is a hydrogen generating cathode.