JPH059774A - Electrolytic cell - Google Patents

Abstract

PURPOSE:To form a passage to uniformize the concn. of an electrolyte in the partition of the electrolytic cell formed with a thin sheet. CONSTITUTION:Ruggednesses are formed on the partition 2 on the anode side of a vertical electrolytic cell unit and on the protrusion 3 on the cathode side and engaged with one another to integrate both partitions, and an electrode plate is joined to the protrusion of the partition to constitute an electrolytic cell. The recessed lines 14 are not formed on a straight line in the vertical direction of the cell but formed on plural split regions. The recessed lines of each region having adjacent passages are joined to one another and further joined to the recessed line of another region at a liq. junction 16. Consequently, the ascending electrolytes are mixed at the junction, and the concn. is uniformly distributed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter press type electrolytic cell, and more particularly to an electrolytic cell having a partition wall for separating an electrolytic solution between adjacent electrode chambers.

[0002]

2. Description of the Related Art A filter press type electrolytic cell is widely used for production of chlorine and caustic soda by electrolysis of salt, electrolysis production of organic substances, electrolysis of seawater and the like.

[0003] A typical salt electrolysis method using a filter press type electrolytic cell is a salt filter press type electrolytic cell in which a plurality of adjacent anode and cathode chambers are electrically and mechanically connected through a partition wall. A multi-pole type in which a large number of polar electrolytic cell units are laminated with a cation exchange membrane, and end electrode chamber units having either an anode or a cathode on one side are laminated at both ends and fixed with a hydraulic press or the like. A filter press type electrolytic cell and a large number of anode chamber units and cathode chamber units having the same electrodes on both sides of a frame-shaped electrode chamber frame are laminated with a cation exchange membrane, and both ends have an anode or cathode on one side. There is a single-pole type filter press type electrolytic cell in which the electrode chamber units are stacked. The electrode chamber unit of a monopolar electrolytic cell is equipped with downcomers and ribs that reinforce the frame-shaped electrode chamber frame and promote the circulation of the electrolytic solution, and electrodes are attached to these ribs, etc. Has no partition for separating the electrolyte.

On the other hand, the unit of the bipolar electrode type electrolytic cell is provided with a partition for separating the anode chamber and the cathode chamber and for transmitting the electrolytic current. An anode and a cathode are attached to the partition walls that separate the anode chamber and the cathode chamber, respectively. One of the anode chamber and the cathode chamber is in an oxidizing environment and the other is in a reducing environment depending on the target electrolytic reaction. Particularly, in salt electrolysis, which is an electrolysis method using a typical ion-exchange membrane, chlorine is generated at the anode and high-concentration sodium hydroxide and hydrogen are generated at the cathode, so that the anode chamber has a high corrosion resistance to chlorine and the like. Titanium, tantalum,
A thin film forming metal such as zirconium or its alloy is used. Further, in the atmosphere of the cathode chamber, titanium absorbs hydrogen and becomes brittle, so that titanium having a large corrosion resistance cannot be used in the cathode chamber. For this reason, iron-based metals such as iron, nickel and stainless steel or alloys thereof are used in the cathode chamber. It is possible to form an electrical connection by forming each electrode chamber with a partition wall made of a metal material and joining them together, but by directly welding titanium on the anode chamber side and iron, nickel, stainless steel, etc. on the cathode chamber side. When joining was attempted, it was not possible to obtain a joined body having practical strength because titanium and the iron-based metal on the cathode chamber side formed an intermetallic compound.

For this reason, many proposals have been made for the bipolar electrolytic cell. For example, Japanese Examined Patent Publication No. 53-5880 discloses that a member on the anode chamber side and a member on the cathode chamber side are connected by a bolt penetrating a partition wall of a synthetic resin material.

Further, in Japanese Patent Publication No. 52-32866, a plate-shaped body in which an iron-based metal and titanium are joined by explosive welding is used as a partition wall, ribs are welded to each surface, and an anode and a cathode are welded to the rib. ing. In Japanese Examined Patent Publication No. 56-36231, a composite material is used in which titanium and iron are sandwiched between copper and three members are joined, and titanium of the composite material and titanium of the partition wall on the anode side of the bipolar electrode unit are welded, Similarly, iron of the composite material and the iron-based metal partition wall on the cathode side are joined by welding.

[0007]

There are various types of partition walls of a bipolar electrode electrolytic cell. In any electrolytic cell, ribs may be joined to the partition walls and electrodes may be attached to the ribs by welding or the like. However, the voltage drop due to the rib is inevitable. Further, it is necessary to use a special method for joining the metal on the cathode side and the metal on the anode side.

In order to solve such a problem, a partition plate having concavo-convex parts to be fitted with each other is manufactured by press working, and a structure having an electrolytic cell unit in which an electrode is bonded to a convex part and a manufacturing method are simple. Japanese Patent Application No. 2-4
Proposed as No. 5855. In an electrolytic cell with a large electrode area, such as electrolysis of salt by the ion-exchange membrane method, if the current distribution in the electrode chamber becomes non-uniform, partial wear of the electrode will proceed or the ion-exchange membrane will partially As unfavorable phenomena occur in the performance of the electrolytic cell, such as deterioration due to
It has been attempted to make the current distribution in the electrode chamber uniform by devising the mounting position of the electrode and the current collecting member so that the current passages of the anode-partition wall-cathode-anode are almost equal.

Further, it has been attempted to make the current distribution uniform in the structure of the electrolytic cell and reduce the distribution of the concentration and temperature of the electrolytic solution in the electrode chamber. In order to reduce the concentration and temperature distribution of the electrolytic solution, it has been attempted to increase the circulation speed or circulation amount of the electrolytic solution that is externally supplied and discharged into the electrode chamber, but increase the circulation amount. Therefore, a large circulation device is required, and sufficient effect cannot be obtained in terms of uniformizing the concentration or temperature of the electrolytic solution.

[0010]

DISCLOSURE OF THE INVENTION According to the present invention, a partition plate in which a partition wall on the anode side and a partition wall on the cathode side of a vertical electrolytic cell unit are formed with concavities and convexities, and both partition walls are superposed and integrated with each other. In the electrolytic cell in which the electrode plate is connected to the convex part of, the concave and convex lines are formed in the vertical direction of the electrolytic cell unit, and the uneven surface is formed by dividing it into a plurality of areas in the height direction. The ridge portion is on the same straight line as the ridge portion of the other region, and the passage of the ridge forms a liquid junction that connects adjacent ridges of the same region and mutually connects ridges of different regions. I contacted you at.

[0011]

Operation: Electrolysis in which an electrode plate is joined to the protrusions of a partition plate in which the partition walls on the anode side and the partition wall on the cathode side of a vertical electrolytic cell unit are formed to fit with each other, and both partition walls are superposed and integrated. In the tank, the groove portion formed by the concave portion of the partition wall surface is not formed on the straight line in the vertical direction of the electrolytic cell, but is formed for each of the regions divided into a plurality of parts, and the groove of each region is formed. Since the adjacent ridges of the passage are connected to each other and the ridges of the other region are connected to each other at the liquid junction, the electrolyte that rises in the electrode chamber due to the action of bubbles generated by electrolysis is The concentration distribution is made uniform by ascending in the electrode chamber while mixing at the junction.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1A is a plan view showing an embodiment of the electrolytic cell of the present invention as seen from the partially cut-away anode side,
FIG. 1B shows a cross-sectional view taken along the line AA of FIG.
FIG. 2 shows a perspective view of a part of the partition plate.

The partition wall 2 on the anode side of the electrolytic cell unit 1 is formed by laminating a thin plate selected from thin film-forming metals such as titanium, zirconium and tantalum and alloys thereof into a pot shape.
The partition wall 3 on the cathode side is a thin plate of iron, nickel, stainless steel or the like processed in the same manner. Each partition wall is attached to the electrolytic cell frame body 4. Both the partition walls are formed with concave and convex portions that fit with each other, and the concave wall 5 and the convex portion 6 are provided on the partition wall on the anode side, and the partition walls on the cathode side are also fitted to the concave and convex parts on the anode side. Similarly, groove-shaped concave portions 7 and convex portions 8 are provided.

On the convex portion of the partition wall on the anode side, an anode 9 in which an anode active coating made of an oxide of a platinum group metal is formed on an expanded metal, a porous plate or the like is provided by welding or the like. A cathode 10 in which a cathode active coating made of a nickel-based or platinum-based metal-based material is formed on an expanded metal, a porous plate or the like is bonded to the convex portion of the partition wall on the cathode side by welding or the like.

The unevenness divides the partition wall into three regions of an upper part 11, a central part 12 and a lower part 13, and the concave and convex parts of the respective regions are concave and convex lines 14 and 15 extending in the vertical direction of the electrolytic cell unit. The liquid junction portion 16 is formed between each region so as to connect the adjacent recessed lines and connect the recessed lines between the upper and lower regions. The electrolytic solution is introduced from the lower part of the electrode chamber and rises along with the gas generated in the electrolytic cell in the recessed portion of the electrode chamber as shown by an arrow in FIG. 1 (A).
It rises while changing the flow path from the liquid junction to the right and left concave portions, and in the process of rising, the mixing of the electrolytic solution progresses and the concentration of the electrolytic solution is made uniform.

It is preferable that the uneven portion formed on the partition plate is formed on the entire surface of the partition plate. In order to provide a large number of flow paths for the electrolytic solution, an electrode is welded to the bottom surface of the recessed portion or the top surface of the protruding portion. It is preferable to have a small area required for mounting.

Further, in the electrolytic cell of the present invention, as shown in a sectional view of the upper part of the electrolytic cell in FIG. 3 and a perspective view of the upper part in FIG. 4, gas and liquid are generated from the gas-liquid mixture generated in the electrode chamber. It is also possible to provide a gas-liquid separation chamber 17 for separating the gas.

In the gas-liquid separation chamber, a partition wall extending vertically so as to enclose the frame body 4 of the electrolytic cell is bent at a right angle to the electrode mounting surface side along a horizontal straight line, and the outer surface of the gas-liquid separation chamber is electrolyzed. It is bent at a right angle with a length corresponding to the thickness of the electrode chamber so as to form the flange 18 of the tank. And the tip 1 of the partition wall
9 is partially bonded to the electrode to fix the electrode.

A communication passage 20 is provided between the gas-liquid separation chamber and the electrode chamber in order to enhance the efficiency of gas-liquid separation.

Further, a partition wall is formed to provide a communication passage 20, and a joining surface 21 for joining to the back side of the flange 18 of the electrolytic cell unit to maintain the mechanical strength of the electrolytic cell unit. Further, the partition wall is formed with a recess 22 for mounting the frame body of the electrolytic cell.

In the passage between the electrode chamber and the gas-liquid separation chamber,
A member formed by processing a thin metal plate in the passage formed between the partition wall and the back side of the flange surface without forming a joint surface with the back surface side of the flange, and only providing the recess 22 for mounting the electrolytic cell frame body. It is also possible to form the communication passage and maintain the strength by attaching the.

Further, FIG. 5 is a sectional view of the lower portion of the electrolytic cell unit, and FIG. 6 is a perspective view of the lower portion of the electrolytic cell unit.
An electrolytic solution dispersion supply chamber 31 that uniformly supplies the electrolytic solution into the electrode chamber may be formed below the electrolytic cell unit. In the electrolyte dispersion supply chamber, a partition wall extending vertically downwardly so as to enclose the frame body 4 of the electrolytic cell is bent at a right angle to the electrode mounting surface side along a horizontal straight line, and the outer surface of the electrolyte dispersion supply chamber is It is bent at a right angle with a length corresponding to the thickness of the electrode chamber so as to form the flange 32 of the electrolytic cell. And the tip 3 of the partition wall
3 is partially bonded to the electrode to fix the electrode.

Between the electrolytic solution dispersion supply chamber and the electrode chamber, a passage 34 having a small cross-sectional area is provided between the electrolytic solution dispersion supply chamber and the electrode chamber so that the electrolytic solution can be rapidly supplied into the electrode chamber. A joining surface 35 is provided which is joined to the back side of the flange 32 of the bath unit and which holds the mechanical strength of the electrolytic bath unit. Further, the partition wall is provided with a recess 36 for mounting the frame body of the electrolytic cell.

The uneven portions provided on the partition walls on the anode side and the cathode side are formed one by one by an ordinary press machine. However, since the partition walls on the anode side and the cathode side can have the same shape, they are formed on the anode side and the cathode side. It is only necessary to prepare the same press mold. Also, by pressing the materials for the partition walls on the anode side and the partition walls on the cathode side one by one, it is possible to form concavities and convexities on both partition walls and at the same time to integrate both partition walls, which simplifies the manufacturing process. Is possible.

The partition wall on the anode side and the partition wall on the cathode side may be directly joined by spot welding, or between the partition wall on the cathode side and the partition wall on the anode side without using permanent connection means such as welding. It is also possible to form an electrical and mechanical connection by fitting the concave and convex portions with a conductive grease interposed.

Further, the electrolytic cell units are stacked to assemble the electrolytic cell to pressurize the inside of the electrode chamber to form a pressure difference between both partition walls and the outside to enhance the contact between the partition walls on the anode side and the partition walls on the cathode side. Alternatively, the space formed by both partition walls and the electrode chamber frame may be made airtight, and this space may be decompressed to form a pressure difference between the space inside the electrode chamber and the contact property between both partition walls.

FIG. 7 shows a cross-sectional view of adjacent electrolytic cell units when the electrolytic cell units are stacked to assemble the electrolytic cell. In the horizontal plane, the convex portions of one polarity are arranged on the same straight line. It is preferable to arrange the adjacent electrolytic cell units so that the convex portions and the concave portions face each other through the ion exchange membrane 23 to make the current distribution uniform.

[0029]

As a result of the present invention, an anode-side partition wall and a cathode-side partition wall of a vertical electrolytic cell unit are formed with recesses and projections which are fitted to each other, and the electrode plates are connected to the projections of the partition wall plate which is integrated by superposing both partition walls. In the electrolytic cell, the groove portion formed by the concave portion of the partition wall surface is not formed on the straight line in the vertical direction of the electrolytic cell,
Since it is formed for each of the regions divided into a plurality of parts, the adjacent ridges of the passages of the ridges of each region are connected to each other and the ridges of the other region are connected to each other at the liquid junction, The electrolytic solution rising in the electrode chamber due to the action of bubbles generated by electrolysis rises in the electrode chamber while being mixed in the liquid junction, and the concentration distribution is made uniform. Further, if a gas-liquid separation chamber and an electrolyte dispersion supply chamber, which are formed by molding a member integrated with the partition plate, are provided, an electrolytic cell having further excellent electrolytic performance can be obtained.

[Brief description of drawings]

FIG. 1 is a plan view showing a first embodiment of the present invention and a sectional view taken along line AA.

FIG. 2 is a plan view of a partition plate with electrodes removed.

FIG. 3 is a cross-sectional view of the upper part of the electrolytic cell.

FIG. 4 is a partially cutaway perspective view showing an embodiment of a gas-liquid separation chamber.

FIG. 5 is a sectional view of a lower portion of the electrolytic cell unit.

FIG. 6 is a partially cutaway perspective view showing an embodiment of an electrolytic solution dispersion supply chamber.

FIG. 7 shows a cross-sectional view in which the electrolytic cell units of the present invention are laminated.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electrolytic cell unit, 2 ... Anode side partition, 3 ... Cathode side partition, 4 ... Electrolyte cell frame, 5 ... Recessed part (anode side), 6 ... Convex part (anode side), 7 ... Recessed part (cathode side) ), 8 ... Convex part (cathode side), 9 ... Anode, 10 ... Cathode, 11 ... Upper part, 12 ... Central part, 13 ... Lower part, 14 ... Recessed line, 15 ... Convex line, 16 ... Liquid junction part, 17 ... Gas-liquid separation chamber, 18 ... Flange, 19 ... Tip part, 20 ... Communication passage, 21 ... Joining surface, 22 ... Recess, 23 ...
Ion exchange membrane, 31 ... Electrolyte dispersion supply chamber, 32 ... Flange, 33 ... Tip, 34 ... Passage, 35 ... Joining surface, 36 ...
Recess

Claims (3)

[Claims] 1. An electrode plate is bonded to a convex portion of a partition plate in which the partition wall on the anode side and the partition wall on the cathode side of a vertical type electrolytic cell unit are formed so as to fit with each other, and both partition walls are superposed and integrated. In the electrolytic cell, the unevenness is formed as a concave line or a convex line extending in the vertical direction of the electrolytic cell unit, and the unevenness is formed by dividing the height direction into a plurality of regions, and the concave line portion of each region is formed. Has a liquid junction part that is on the same straight line as the ridge portion of the other area and that joins the adjacent ridges of the same area and joins the ridges of the adjacent area in the joining portion of the adjacent areas. Electrolyzer characterized by 2. A gas-liquid separation chamber, which is formed of a member integrated with a partition plate, is provided at the upper part of the electrolytic cell unit, and a passage is provided between the electrode chamber and the electrode chamber for partitioning the two chambers. The electrolytic cell according to claim 1, wherein: 3. An electrolytic solution dispersion supply chamber, which is formed of a member integrated with a partition plate, is provided in the lower portion of the electrolytic cell unit, and a passage is defined between the electrode chamber and the electrolytic solution dispersion supply chamber. The electrolytic cell according to any one of claims 1 and 2, wherein: