JP3110720B2 - Gas-liquid separation method in an ion exchange membrane electrolytic cell - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-liquid separation method in an electrolytic cell, and more particularly to a method for performing gas-liquid separation at an upper portion of an electrode chamber of an electrolytic solution containing bubbles generated by an electrolytic reaction as in an ion-exchange membrane alkali chloride electrolytic cell. The present invention relates to a gas-liquid separation method.

[0002]

2. Description of the Related Art An ion exchange membrane filter press type electrolytic cell is widely used for the production of chlorine and caustic soda by electrolysis of saline solution, organic electrolysis, seawater electrolysis and the like. The filter press type electrolytic cell sandwiches a cation exchange membrane with a bipolar electrolytic cell unit in which the partition walls of the anode chamber and the cathode chamber are electrically and mechanically connected via a conductive member or by means such as pressure welding. There is a multi-pole filter press type electrolytic cell in which a large number of layers are laminated, and an end electrolytic cell unit having either an anode or a cathode on one side is fixed and fixed with a hydraulic press or the like. A monopolar type in which a large number of anode chamber units and cathode chamber units having an anode or a cathode on both sides of a frame are laminated via a cation exchange membrane, and an end pole chamber unit having an anode or a cathode on only one side is laminated on both ends. There is a filter press type electrolytic cell.

[0003] In an ion exchange membrane method salt electrolyzer, chlorine gas is generated at the anode, and high concentration sodium hydroxide and hydrogen are generated at the cathode, so that a stable passivation film is formed on the surface of the anode chamber in corrosion resistance. In the cathode chamber, an alkali-resistant iron-based metal such as nickel or stainless steel or an alloy thereof is used in place of titanium which absorbs hydrogen and becomes brittle. In each electrode chamber, an anode and a cathode are attached to a conductive rib connected to a partition, and an electrolyte supply nozzle and an electrolyte with a reduced or increased concentration, a gas as a product of an electrolytic reaction, and air bubbles are provided on a side wall. Is provided with a discharge nozzle for the electrolytic solution mixed with.

[0004] As the anode, a perforated plate such as titanium, an expanded metal or the like as a base material, the surface of which is coated with an oxide of a platinum group metal such as ruthenium, iridium or palladium is used. As the cathode, there is used a cathode whose base material is a porous plate of iron, stainless steel, nickel or the like, expanded metal, or the like, and whose surface is coated with a cathode catalyst material such as a nickel-based or platinum group metal-based. As the ion exchange membrane, a fluorinated resin-based cation exchange membrane having a sulfonic acid group, a carboxylic acid group and the like is used.

[0005]

In an electrolytic cell of a filter press type ion-exchange membrane method, when an electrolysis reaction such as electrolysis of salt is performed to generate a gas, an anolyte or a catholyte containing bubbles is converted into an electrode chamber. When the air is extracted from the electrode, the pressure in the electrode chamber fluctuates due to the bubbles.

[0006] The anolyte or catholyte in the electrode chamber of a generally used vertical alkaline chloride electrolyzer has a higher bubble ratio, which is the proportion of bubbles, toward the upper part due to bubbles generated at the electrode. As the air bubbles get closer, the air bubbles gather to form a foam layer, and a gas phase formed of gas separated from the foam is formed at the top. As a result, when trying to discharge the electrolyte and generated gas from the upper part of the electrode chamber, the outflow state is a gas-liquid mixed phase,
A complicated flow that fluctuates the pressure in the electrode chamber is generated by a bubble flow in which a liquid phase and a gas phase are mixed, a plug flow that blocks a pipe, and a wavy flow. In particular, chlorine bubbles formed on the anode chamber side are less likely to disappear than hydrogen bubbles formed from caustic soda and hydrogen on the cathode chamber side due to salt water viscosity, surface tension, etc. cause. Therefore, pressure fluctuation in the anode chamber, is different 50~200mmH ₂ O, optionally by electrolysis conditions 300mmH
Over ₂ O, the ion exchange membrane constantly vibrates and repeatedly comes into contact with and separates from the electrode surface, causing frictional damage on the surface of the cation exchange membrane, and cracking of the cation exchange membrane due to fatigue due to vibration. Occurs. as a result,
The characteristics of the cation exchange membrane are degraded, and the electrode is generally damaged by alkali flowing into the anode chamber from the cathode chamber where the pressure in the electrode chamber is high, which adversely affects the life of the electrode.

Therefore, in a saline ion-exchange membrane electrolytic cell, a method of keeping the pressure of the cathode chamber larger than the maximum fluctuation value of the anode chamber pressure and constantly pressing the membrane against the anode surface to prevent vibration is provided. A method in which a chamber higher than the level of the electrolyte is provided at the upper part, a gas-liquid separation zone is formed in the chamber, and the bubbles are spontaneously defoamed in the chamber and taken out as a wavy flow or a stratified flow from the discharge nozzle on the side wall. In the upper wall of the electrode chamber as shown in the publication,
There has been proposed a method of providing a nozzle which is opened to the inside by not less than mm and has a liquid flow rate in the nozzle of 0.5 to 20 m / sec.

However, in the method of applying a pressure larger than the maximum value of the pressure fluctuation of the anode chamber to the cathode chamber, the membrane always excessively presses the anode surface made of expanded metal or perforated plate, and cuts into the opening of the anode. Therefore, not only the anode overvoltage of chlorine generation is increased and the electrolytic cell voltage is increased by several to several tens of mV to cause power loss, but also in the long term, the erosion of the catalytically active coating of the anode due to alkali reversely migrating from the cathode side. However, there is a disadvantage that the life of the electrode is shortened largely as compared with the case where the pressure of the cathode pressurization is small.

Although a method of providing a gas-liquid separation zone by raising the upper part of the electrode chamber is effective for preventing pressure fluctuation, the material cost and the processing cost for the increase in the capacity of the electrode chamber are likely to be high. Furthermore, the method of inserting the discharge nozzle from the upper wall surface of the electrode chamber requires the operation of the electrolytic cell because it is necessary to determine the size of the discharge nozzle according to the ratio of the amount of generated gas and the circulation amount of the electrolyte in the electrode chamber. In the case of a bipolar electrolytic cell, it is necessary to take measures to prevent corrosion due to leak current flowing through the discharge nozzle.

Further, in the method using a discharge nozzle, the surface of the ion exchange membrane at the upper part of the electrode chamber is in a dry state, and the gaseous chlorine permeating the cation exchange membrane adversely affects the cation exchange membrane. It has been clarified that it is necessary to provide, by welding or the like, a weir for overflowing the electrolyte in order to keep the surface of the cation exchange membrane in a wet state on the upper partition wall surface (see "Soda and Chlorine" Vol. 41). No. 4, page 18 (April 1990)).

On the other hand, a method of manufacturing a pot-like electrode chamber of a bipolar electrolytic cell using a thin plate made of titanium, nickel, stainless steel or the like by a die press is easy to manufacture and has high mass productivity. This is a preferable manufacturing method because it is extremely effective in reducing the cost of the electrolytic cell. However, adding a gas-liquid separation chamber or attaching a weir or the like by welding loses the characteristics of press molding.

[0012]

According to the present invention, there is provided a gas-liquid separation method for an ion-exchange membrane electrolytic cell, wherein a gas-liquid mixture generated in an electrode chamber is parallel to an electrode surface formed on the upper part of the electrolytic cell and has a cross-sectional area. This is a gas-liquid separation method in an ion-exchange membrane electrolytic cell in which a small passage is discharged from a gap and then discharged from a gap, thereby performing gas-liquid separation by compression due to inflow into the passage having a small cross-sectional area and decompression due to discharge from the gap. .
In addition, one surface of the passage formed in the upper part of the electrolytic cell is formed by the side wall of the U-shaped pipe whose upper part is open, and the gap is formed by the side wall of the U-shaped pipe and the wall provided on the upper part of the U-shaped pipe. And a gas-liquid separation method in an ion-exchange membrane electrolytic cell that performs gas-liquid separation when discharged into a U-shaped conduit.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The gas-liquid separation method according to the present invention is characterized in that a gas-liquid mixture generated in an electrode chamber is raised in a passage having a small cross-sectional area parallel to an electrode surface formed on the upper part of an electrolytic cell. Is a gas-liquid separation method in an ion-exchange membrane electrolytic cell in which gas-liquid separation is performed by compression due to inflow into a passage having a small cross-sectional area and pressure reduction due to discharge from a gap. Then, the upper space of the electrode chamber is narrowed by the conduit having a U-shaped cross section provided at the upper part of the electrode chamber, and as a result, the flow path of the electrolytic solution containing air bubbles is narrowed, and the air bubbles are brought into contact with each other. It expands and is compressed from a narrow gap formed between the upper wall surface of the electrode chamber and the side wall of the conduit and flows into the conduit. Many of the bubbles expanded during the inflow burst due to the change in compression and pressure, and the electrolyte and gas containing bubbles remaining in the pipe flow toward the discharge nozzle. Further, when air bubbles are clogged with foam in the pipeline, the gas flows into the space formed between the U-shaped pipeline and the partition wall by the communication passage provided on the side wall of the pipeline and is bypassed to the discharge nozzle. be able to.

Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a diagram showing one embodiment of an electrolytic cell used for a gas-liquid separation method in an ion exchange membrane electrolytic cell of the present invention, and shows a plan view in which a part of a bipolar electrolytic cell unit is cut away. FIG. 2 is a cross-sectional view of FIG. 1 taken along line AA. The bipolar cell unit 1 has an anode chamber 3 and a cathode chamber 4 formed on the left and right with a frame frame 2 formed of a rigid body such as carbon steel as a skeleton. The partition wall 5 on the side of the anode chamber and iron,
A partition 6 on the cathode chamber side, which is also made of a thin plate made of stainless steel, nickel or the like and processed into a pot shape, is electrically and mechanically connected by a connecting portion 7. In the anode chamber and the cathode chamber, an anode 10 having a coating containing a platinum group metal or oxide formed on conductive ribs 8 and 9 bonded to a partition wall respectively, and a cathode having a nickel or platinum group cathode active material coated thereon 11 is attached, and U-shaped conduits 12 and 13 are provided in the upper part of the electrode chamber. The U-shaped conduit is attached with an interval between the electrode and the partition wall, and between the side wall 14 on the electrode surface side of the U-shaped conduit and the upper wall 15 of the electrode chamber, the raised electrolytic solution and bubbles flow. A narrow gap 16 is formed, and a communication path 17 is provided on a wall surface on the partition wall side of the U-shaped pipe.

One end of the U-shaped conduit is connected to a discharge nozzle 19 attached to the side wall 18 of the electrolytic cell unit for taking out the electrolytic solution and gas to the outside. The nozzle 20 is attached, and a mounting arm for attaching the electrolytic cell unit to the gantry is provided on a side wall of the electrolytic cell unit.

FIG. 3 shows a view in which a U-shaped pipe is attached from the electrolyte discharge nozzle to the inside of the electrolytic cell. The U-shaped pipe 1 is connected to the discharge nozzle 19 provided on the side wall 18 of the electrolytic cell unit.
2, 13 are attached. For the U-shaped conduit, it is preferable to use a synthetic resin such as a fluororesin or polypropylene in order to prevent electrolytic corrosion in the electrolytic cell. The U-shaped pipe is attached to the discharge nozzle 19 via a gasket 21,
A cut-out portion 22 serving as a guide for a U-shaped conduit is formed in the conductive rib 8 for attaching an electrode. A communication passage 17 is provided on a side wall of the U-shaped pipe.

FIG. 4 is a diagram showing a bipolar electrolytic cell.
Five bipolar electrode unit 1 and end anode unit 2
3 and an end cathode unit 24. A cation exchange membrane 25 is attached between the electrolytic cell units, placed on a gantry 26, and fixed by a hydraulic press, a tie rod, or the like. Discharge nozzle 1 on unit side wall
9. A pipeline is connected to the supply nozzle 20 to supply an electrolytic current to the electrolytic cell units at both ends.

FIG. 5 is a view for explaining the flow of the electrolytic solution to the U-shaped pipe provided in the electrolytic cell. The U-shaped conduit equalizes the upward flow of the electrolyte in a gas-liquid mixed phase over the entire electrode chamber, holds the liquid surface 28 in the partition-side space 27 of the electrode chamber, and forms a gas bypass flow path. For this purpose, a height corresponding to the length between both side walls of the electrode chamber is required. Also, U
The height of the side wall of the mold pipe must be a distance which promotes coalescence of bubbles in the rising path of the electrolyte on the electrode side, that is, the height, the current density is 3 kA / m ² , the temperature is 85 ° C., and the salt water concentration is 20.
According to the results obtained by experiments under standard electrolysis conditions of 0 g / l, it was found that 4% or more, and preferably 5% or more, of the liquid surface depth of the electrolytic cell was required.

The electrolytic space 29 of the anode chamber is a region in which chlorine bubbles are freely rising in the salt solution of the electrolyte while receiving complicated fluid resistance, but the rising flow is separated by a U-shaped conduit. When reaching the portion, most of the bubbles enter the flow path of the electrode-side space 30 and rise together with the liquid, whereas the partition-side space 27
The liquid surface 28 is formed without any rise in gas-liquid. In order to form the liquid surface 28 in the partition-side space and to form an upward flow in the electrode-side space, it is necessary that the space on the electrode side be at least twice as large as the space on the partition-side. Is preferably as small as possible without causing capillary action, and more preferably 2 to 4 mm. Also, as shown in FIG. 5, a difference is formed between the liquid levels on both sides of the U-shaped conduit. This is because the generated gas bubbles rise mainly on the electrode side in the electrode chamber, so that a difference occurs between the density of the electrolyte in the region on the partition side and the density on the electrode side, and as a result, the U-shaped conduit and the partition This is because the liquid level of the space formed between them is formed on the electrode side of the U-shaped conduit.

[0020] The width of the U-shaped conduit is such that the gas-liquid appropriate for the supply amount of the electrolyte and the amount of generated gas flows into the conduit and forms the cross-sectional area of the passage necessary for moving the discharge nozzle without confusion. It is necessary, and it is preferable that it is 10 mm or more. Also U
The larger the height of the U-shaped conduit is, the larger the flow area of the electrolyte flows as the height increases, but the current distribution to the upper end of the electrode through the conductive rib may be insufficient. The height is preferably set to 60 to 100 mm. In particular,
In the electrolytic cell shown in the embodiment, since the gas-phase space is provided between the U-shaped pipe and the partition wall to form a bypass for generated gas, the width of the U-shaped pipe can be reduced.

Further, the gas-liquid multiphase flow that has risen in the electrode side space reaches the upper wall surface of the electrode chamber, and the gas flows from the gap formed by the upper wall surface of the electrode chamber and the upper side wall of the U-shaped conduit on the electrode side. While flowing into the type pipe and passing through the gap, many bubbles burst, and the electrolyte containing the foam is taken out into the U-type pipe and from the U-type pipe to the outside through the discharge nozzle. The gap formed between the side wall of the U-shaped conduit and the upper wall of the electrode chamber is 3
If the gap is large, it is not preferable because the flow path resistance increases, and conversely, the pressure fluctuation increases. The fluctuation is undesirably large.

According to the electrolysis method of the present invention, the gas-liquid mixture having a small cross-sectional area is provided at the upper part of the electrode chamber, and the gas-liquid mixture is discharged from the gap at the upper part of the flow path. The bubble inside is compressed while rising in the narrowed flow path, unites with the nearby bubble and expands, then flows into the pipeline from the narrow gap, and the pressure change of compression and expansion during inflow is Many of them rupture and undergo gas-liquid separation.

[0023]

【Example】

Example 1 A titanium plate having a thickness of 1 mm and a stainless steel plate were formed into a 140 mm long × 93.5 cm wide × 3 cm deep anode chamber and a cathode chamber by a press die, and a notch for fixing a U-shaped conduit thereto. 4 mm thick, 3 cm wide, 13 long with
Five conductive ribs of 0 cm titanium and stainless steel were attached by welding at an interval of 18 cm from the center of the width of the electrode chamber, and an electrolyte supply nozzle was formed below the side walls of both electrode chambers as an electrolyte solution supply nozzle using the same material as the electrode chamber with an inner diameter of 13 mm and an outer diameter of 17. 3mm, length 100mm
A short pipe with a flange is attached, and a flanged square pipe of the same material as the electrode chamber and having a thickness of 1.5 mm, 6.5 cm x 3 cm x 10 cm, is attached as a discharge nozzle for the electrolytic solution and the gas produced by the electrolysis. Was. Next, a frame-like frame, an anode chamber and a cathode chamber were mounted on a cladding body of titanium and copper attached to the anode chamber side and a partition on the cathode chamber side as disclosed in JP-A-3-24.
As described in JP-A-0984, brazing was performed in an electric furnace using solder to join the partition walls of both electrode chambers and to integrate the frame-shaped frame.

Thereafter, an expanded metal having an aperture ratio of 35% obtained from a titanium plate having a thickness of 1 mm and having an anode active coating containing a noble metal oxide, having a length of 1.399 m, was obtained.
× 0.933 m width Electrode effective area 1.3 m ² anode (manufactured by Permelec Electrode Co., Ltd.) and expanded metal with a 37% aperture ratio obtained from a 1.5 mm thick stainless steel plate coated with a nickel-based active cathode And a cathode having the same dimensions as the anode was spot-welded to the conductive rib to produce a bipolar electrolytic cell unit.

The anode chamber and the cathode chamber each form a single end anode unit and a single end cathode unit. Three double-electrode type electrolytic cell units are provided with corrosion-resistant gaskets on the flange surface. An anode unit and an end cathode unit were provided, and an ion exchange membrane was sandwiched and laminated. The distance between the electrodes was 2 mm, and Nafion N9 was used as a cation exchange membrane.
A bipolar electrolytic cell having four 54 (trade name of DuPont) was assembled. Next, a fluororesin thickness 1.5 mm,
A U-shaped conduit having a height of 57 mm, a width of 18 mm, a total length of 1025 mm, an upper opening length of 93 mm, and having three 5 mm holes on the side wall of the partition wall, the upper wall surface of the electrode chamber and the side wall of the U-shaped conduit Is 5 mm, and the distance from the electrode surface is 8 m.
m, and the distance between the partition and the partition was 4 mm, and was connected to the discharge nozzle.

Each nozzle has a main pipe for supplying electrolyte and an electrolyte.
And a flexible pipe made of fluororesin
Connected via a DC power supply and the anode terminal of the electrolytic cell,
The electrolytic cell was completed by connecting to a cathode terminal. In the cathode compartment
Supply pure water and supply 300g / l saline to anode chamber
And 32% caustic soda from the cathode compartment and from the anode compartment
Return the saline solution concentration to 200 g / l, take out the saline solution,
Dismantling temperature 85 ° C, electrolysis current 5.2kA, current density 3kA
/ M ^TwoFor 30 days. Caustic soda during this time
Current efficiency of 96.2% of 4 pairs of electrolyzer units
The average cell voltage was 3.05 V and the pressure fluctuation in the anode chamber was 15
mmH_TwoThe state was extremely stable within O 2. Then
To confirm pressure fluctuation under high load electrolysis conditions
Current density 4 kA / m^TwoReturn the brine supply and circulate the brine
To increase the anode to 2-4 times the standard supply
The indoor pressure fluctuation was measured, and the results are shown in Table 1. Also, electrolysis
The tank operation was stopped, and the cation exchange membrane was inspected.
No abnormalities such as color and deterioration were observed.

Example 2 The same procedure as in Example 1 was carried out except that a U-shaped pipe having a distance of 10 mm between the electrode side wall of the U-shaped pipe of Example 1 and the upper wall of the anode chamber was attached. After operating for 15 days under the conditions, the current efficiency was 95.6%, the average cell voltage was 3.06 V,
The initial electrolysis performance was almost the same as in Example 1. The fluctuation of the anode chamber pressure was measured in the same manner as in Example 1, and the results are shown in Table 1. After the operation was stopped, discoloration with a width of about 5 mm was observed on the upper portion of the cation exchange membrane. Example 3 The same conditions as in Example 1 were adopted, except that a U-shaped conduit having a distance of 15 mm between the electrode side wall of the U-shaped conduit of Example 1 and the upper wall surface of the anode chamber was attached. As a result of operating for a day, the current efficiency was 95.2%, the average cell voltage was 3.09 V,
The initial electrolysis performance was almost the same as in Example 1. The fluctuation of the anode chamber pressure was measured in the same manner as in Example 1, and the results are shown in Table 1. Further, after the operation was stopped, the discoloration of the upper part of the cation exchange membrane which was considered to be caused by chlorine having a width of about 10 mm was observed.

[0028]

[Table 1] Pressure fluctuation (mmH ₂ O) Salt water flow rate Distance between U-shaped pipe side wall and upper wall (liter / min) 5 mm 10 mm 15 mm ────────────────── ─────────── 2 (1.5) 10 60 80 3 (2.3) 20 140 160 4 (3.1) 20 150 180 5 (3.8) 30 180 190

Comparative Example 1 The U-shaped conduit was removed from the electrolytic cell of Example 2, and the electrolytic cell was reassembled using the cation exchange membrane used in Example 2 under the same conditions as in Example 2. I drove for 15 days. The current efficiency was 94.8%, the average cell voltage was 3.11 V, and a decrease in electrolytic performance was observed. The pressure in the anode chamber is -10 to 12
The value constantly fluctuated in the range of 0 mmH ₂ O and was larger than that in Example 2. A plug flow occurred in the discharge nozzle, and an intermittent outflow phenomenon was observed. After the operation was stopped, the cation exchange membrane was inspected. As a result, a brown discoloration of about 100 mm in width was seen at the top of the cation exchange membrane, and discoloration and small blisters of about 2 mm in diameter were scattered to 35 mm below the lower side of the discharge nozzle. In addition, black-brown discoloration and abrasions which appeared to have touched the file-like active cathode surface were partially observed.

COMPARATIVE EXAMPLE 2 Instead of a U-shaped conduit, the distance between the upper end of an L-shaped member having a height of 57 mm and a width of 18 mm and the upper wall of the electrode chamber was 5 mm, and the distance between the electrodes was 8 mm. After welding and mounting, the discharge nozzle on the side wall of the electrode chamber was modified, and a discharge nozzle with an inner diameter of 25 mm x an outer diameter of 27.2 mm was provided at the bottom of the cabinet to repair the electrode and incorporated into the electrolytic cell. It was operated for 15 days under the same standard electrolysis conditions. Current efficiency is 9
5.8% and the cell voltage was 3.08V. The electrode chamber pressure greatly fluctuated in the range of −20 to 180 mmH ₂ O, and the outflow state of gas and liquid from the discharge nozzle was a typical intermittent plug flow. The current density and the circulation magnification were 4 KA / m ² , respectively.
Pressure fluctuation under the condition changed to 3 times is -40 to 200 mmH
It was increased to ₂ O. At the top of the opened membrane, a black-brown change was seen, which appeared to have touched the active cathode.

[0031]

As described above, in the electrolysis method of the present invention, the mixed fluid of the electrolytic solution and the generated gas generated in the electrode chamber is raised through the small flow path and then discharged from the gap. By discharging the liquid from the discharge nozzle after liquid separation, fluctuation of the pressure in the electrode chamber and vibration of the ion exchange membrane due to the fluctuation can be prevented, and the life of the ion exchange membrane and the electrode can be extended.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of an electrolytic cell used for a gas-liquid separation method in an ion exchange electrolytic cell of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a diagram illustrating attachment of a U-shaped pipe from the side wall of the electrolytic cell unit to the inside of the electrolytic cell.

FIG. 4 is a view showing a bipolar electrolytic cell.

FIG. 5 is a diagram illustrating a flow of an electrolytic solution to a U-shaped pipe provided in an electrolytic cell.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electrolyzer unit, 2 ... Frame-shaped frame, 3 ... Anode room, 4 ... Cathode room, 5 ... Anode room side partition, 6 ... Cathode room side partition, 7 ... Connection part, 8, 9 ... Conductive rib, 10 ... Anode, 1
DESCRIPTION OF SYMBOLS 1 ... Cathode, 12, 13 ... U-shaped conduit, 14 ... Side wall on the electrode surface side of U-shaped conduit, 15 ... Upper wall of electrode chamber, 16 ... Gap, 1
7 ... communication passage, 18 ... side wall, 19 ... discharge nozzle, 20 ...
Supply nozzle, 21 gasket, 22 notch, 2
3 ... End anode unit, 24 ... End cathode unit, 25
... Cation exchange membrane, 26 ... Stand, 27 ... Partition side space, 2
8: liquid level, 29: electrolytic space part, 30: electrode side space

Claims (2)

(57) [Claims] In a gas-liquid separation method in an ion-exchange membrane electrolytic cell, a gas-liquid mixture generated in an electrode chamber is raised in a passage parallel to an electrode surface formed in an upper part of the electrolytic cell and having a small cross-sectional area. A gas-liquid separation method in an ion exchange membrane electrolytic cell, characterized in that gas-liquid separation is performed by compression by flowing into a passage having a small cross-sectional area by discharging from a gap and decompression by discharging from the gap. 2. One side of a passage formed in an upper part of an electrolytic cell is formed by a side wall of a U-shaped conduit whose upper part is open, and a gap is provided on a side wall of the U-shaped conduit and an upper part of the U-shaped conduit. The gas-liquid separation method for an ion-exchange membrane electrolytic cell according to claim 1, wherein the gas-liquid separation is formed between the wall and the wall, and the gas-liquid separation is performed when the gas is discharged to a U-shaped conduit.