JPH0413432B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention is applicable to various applications such as recovery and purification of various metals, electroplating of particles, and decomposition of organic compounds and/or cyanide compounds. This invention relates to an electrolytic method using a fluidized bed and an electrolytic cell used in electrochemical reactions.

(Prior art) Using electrode particles made of fluidized metal particles, etc.
Fluidized bed electrolysis for recovering metals from solutions and plating particles is well known (Japanese Patent Laid-Open No. 53-92302).
(U.S. Pat. No. 3,457,152, U.S. Pat. No. 4,212,722). Before this fluidized bed electrolysis method was developed, the following methods had been tried to recover metals from solutions.

(a) Add a reducing agent to the solution and deposit the metal directly in the solution.

(b) A solution containing metal ions and metal cyanide complex ions is introduced into an ion exchange resin tower to fix the metal ions and metal cyanide complex ions to the ion exchange resin.

(c) The solution is electrolyzed in a low current density electrolytic cell to deposit the metal on the cathode.

Although metals can be recovered from solutions using these methods, each method has the following drawbacks. In other words, method (a) has the disadvantages of increased processing liquid volume, long reaction time, and high operating costs, while method (b) is easy to operate, but requires equipment construction costs, regenerating chemicals, etc. However, although method (c) is suitable for waste liquids containing high concentrations of metals, it is not economical unless the current density is further reduced in the case of waste liquids with low concentrations. It is not possible to obtain a high current efficiency, the electrolytic cell becomes large and the construction cost increases, and because the electrolytic cell is operated at a low current density, the deposited state becomes extremely plated, making it difficult to remove it from the cathode. In practice, the drawback was that it was necessary to redissolve the metal using a metal stripping agent.

In addition to recovering metals from solutions, similar methods can also be used when refining metals containing small amounts of impurities into high-purity metals, or when electroplating desired metals onto powder or granules. was adopted, and similar shortcomings were pointed out.

Fluidized bed electrolysis technology was developed to overcome these shortcomings. Fine particles are housed in an electrode chamber on the side of the electrolyte to be treated, and these particles are electrolyzed using the electrolyte alone or with the electrolyte and a supply gas. By causing the electrode to flow, the surface area of the electrode can be dramatically increased, making it possible to deposit metal on the electrode particles with high current efficiency and low electrolytic voltage.

However, because conventional fluidized bed electrolysis uses a plate-shaped electrode as the counter electrode, particles in the fluidized state and particles generated on the counter electrode chamber side between the counter electrode and the diaphragm that partitions the two electrode chambers. If gas enters, the electrolytic voltage increases and the electrolytic conditions become unstable, and the diaphragm becomes wavy and damaged. Furthermore, if the degree of curvature is large, the fluidization of electrode particles is inhibited, making the electrolysis even more difficult. It has the disadvantage of making conditions unstable.

(Problems to be Solved by the Invention) The present invention prevents the main electrode particles that rise in the main electrode chamber with the upward flow of the electrolyte from flowing out of the main electrode chamber together with the electrolyte, and In other words, the auxiliary electrode is made porous, and the gas generated on the auxiliary electrode surface is discharged to the back side of the electrode, thereby reducing the uneven current distribution caused by the presence of gas between the electrode and the diaphragm, and the resulting diaphragm. The purpose is to prevent the negative effects of

[Structure of the invention]

The present invention first stores main electrode particles in the main electrode chamber of an electrolytic cell divided into a main electrode chamber and an auxiliary electrode chamber by a diaphragm, and supplies an electrolytic solution to the main electrode chamber to bring the main electrode particles into a fluid state. In an electrolysis method using a fluidized bed that performs electrolysis while maintaining the electrolyte, the flow rate of the upward flow of electrolyte solution is reduced in the upper part of the main electrode chamber, and the main electrode particles accompanying the upward flow are separated from the upward flow. This is an electrolysis method that uses a fluidized bed to prevent leakage to the outside, and to conduct electrolysis while a porous auxiliary electrode is closely attached to the diaphragm and gas generated on the surface of the auxiliary electrode is discharged to the back of the auxiliary electrode. In an electrolytic cell in which main electrode particles are stored in the main electrode chamber of a cylindrical electrolytic cell divided into a main electrode chamber and an auxiliary electrode chamber by a diaphragm, an electrolyte supply port is provided at the bottom of the main electrode chamber, and the main electrode chamber A fluidized particle dispersion prevention tower whose cross-sectional area gradually increases toward the top is installed at the top of the tower, an electrolyte outlet is provided on the wall of the fluidized particle dispersion prevention tower, and a porous auxiliary electrode is installed in the diaphragm. This is an electrolytic cell that uses a close fluidized bed.

The method and electrolytic cell of the present invention are mainly used for recovering and refining metals, plating powder and granules, and decomposing organic compounds and/or cyanide compounds.

When collecting and refining metals and plating powder or granules, electrolysis is performed using the main electrode chamber as a cathode chamber and the auxiliary electrode chamber as an anode chamber. Further, when decomposing an organic compound and/or a cyanide compound, the decomposition reaction is carried out using the main electrode chamber as an anode chamber and the auxiliary electrode chamber as a cathode chamber. Therefore, in the case of metal recovery, etc., the main electrode particles, the auxiliary electrode, and the main electrode of the main electrode chamber become the cathode particles, anode, and cathode, respectively, and in the case of decomposition of organic compounds and/or cyanide compounds, They become an anode particle, a cathode, and an anode, respectively.

When using cathode particles, the material is as follows:
Metals such as gold, silver, copper, nickel, and lead, their oxides, sulfides, or alloys thereof, and conductive nonmetals such as graphite and activated carbon can be used, as well as graphite, glass, and ceramics. Particles coated with metals such as gold, silver, copper, nickel, and lead can also be used.
When using anode particles, noble metals, particles of graphite, glass, ceramic, etc. or titanium are used.
It is possible to use materials that are coated with noble metal oxides, lead, etc., and which are not dissolved in solution even when electrolyzed. The particle size of this cathode or anode particle is 0.05
~3.0mm, preferably 0.1~0.5mm. or,
As the material for the cathode and anode, commonly used materials such as graphite, stainless steel, platinum, titanium coated with a noble metal oxide, and ferrite can be used.

The diaphragm that separates the main electrode chamber and the auxiliary electrode chamber may be non-porous or porous as long as it allows electrical ions to pass through, but if a porous diaphragm is used, the pore diameter is It is smaller than the particle size of the particles, preferably 10 to 100μ. The material of the diaphragm is preferably a non-conductive organic compound or a non-conductive inorganic compound such as nylon, polyethylene, polypropylene, polytetrafluoroethylene. Also,
This diaphragm may have an ion exchange group.

The auxiliary electrode has a perforated shape and is brought into close contact with the diaphragm in order to discharge gas generated between the electrode and the diaphragm to the back side of the electrode. The perforated auxiliary electrode may be made of expanded metal, a plate with perforations, a porous material, or a sintered material.

Electrolysis is performed by supplying an electrolytic solution to the main electrode chamber of the electrolytic cell made up of these various elements. An appropriate electrolyte may be selected depending on the purpose of electrolysis, and when recovering metals, for example, precious metals such as gold, platinum, and silver, polluting metals such as cadmium and chromium, and zinc, gallium, A solution containing at least a portion of various metals such as bismuth, other metals such as aluminum,
In particular, use plating waste liquid or etching liquid.

In addition, when refining metals, a solution containing the metal to be purified with relatively high purity and a small amount of impurities is used, and when plating powder fluid, a solution of the metal to be plated is used. .

The main electrode particles are brought into a fluid state by the rising force of the electrolytic solution supplied into the electrolytic cell. This upward force is weakened by enlarging the passage area and the fluid state is maintained. Here, "fluid state" means
This refers to the state in which the solution passes through while the main electrode particles touch each other in the solution and separate from each other.

When electrolysis is performed in this state, the main electrode particles in a fluidized state are used, so the surface area of the main electrode becomes extremely large, lowering the current density, and the main electrode particles collide with each other, forming an electric double layer. Since it is unstable, electrolysis can be performed with low electrolysis voltage and high current efficiency. Further, by utilizing the deposition potential difference between different metals, only a specific metal can be selectively deposited, which is convenient for metal purification.

Furthermore, since the auxiliary electrode is brought into close contact with the diaphragm and the electrode is porous, generated gas may enter between the auxiliary electrode and the diaphragm, increasing the electrolytic voltage.
The diaphragm will not wave or be damaged.

In the case of recovering or refining metals or plating powder or granules, cathode particles whose surfaces are coated with metal are produced by the electrolytic operation, and these are taken out of the electrolytic cell. In the case of powder plating, the desired granules are taken out, so they can be used as they are for various purposes.In the case of metal recovery and refining, unless the precipitated metal and the cathode particles have the same components, It is necessary to separate the deposited metal and the cathode particles. For separation, conventional separation means such as dry separation method or wet separation method may be used as is. In order to separate metal from cathode particles by a dry separation method, for example, in the case of gold or platinum, the following procedure may be performed.
When cathode particles coated with gold are melted and oxygen gas, chlorine gas, etc. Glass, etc., becomes slag, floats on the molten metal, and is separated. Thereafter, by cooling and solidifying, gold or platinum containing almost no impurities other than platinum and gold can be obtained. In addition, when an alloy is precipitated from a dilute solution containing a noble metal and a base metal, it can be redissolved and separated using a normal wet separation method.
This redissolved liquid does not contain organic substances other than metal elements, and can be economically recovered because a small amount of highly concentrated liquid can be obtained.

Further, in the case of decomposing organic compounds and/or cyanide compounds, no separation operation is necessary because nothing is deposited on the anode particles.

The current efficiency for metal recovery by the method of the present invention is
The recovery rate of metal from the solution is 10% or more, which varies depending on the metal content and electrolysis time, but in one operation,
When the content is low, it is almost 100% at low power, and when the content is relatively high, it is more than 90%. In the latter case as well, the metal can be recovered almost quantitatively by circulating the solution.

Hereinafter, the present invention will be explained in more detail based on a first embodiment and a second embodiment shown in the accompanying drawings. In both examples, the present invention will be described as an electrolytic cell for metal recovery, purification, and plating of powder and granular materials, with the main electrode as the cathode and the auxiliary electrode as the anode, but the present invention is not limited to these. do not have.

FIG. 1 is a partially cutaway front view showing a first embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line -- in FIG.

The electrolytic cell body 1 consists of a dish-shaped lower frame 3 in which a solution supply port 2 is connected downward, and a cylindrical cathode 4. Both upper and lower ends of the cathode 4 are bent outward. has been done. A perforated lower diaphragm 7 whose periphery is sandwiched by a pair of gaskets 6 is placed on the flange portion 5 at the periphery of the lower frame 3, and a recessed portion is provided on the upper center surface of the lower diaphragm 7. 8, and a solution dispersion plate 10 having a large number of vertically perforated holes 9 is placed in a portion other than the recess 8 and the peripheral edge. Outward bent portion 11 at the bottom of the cathode 4
is placed on the solution distribution plate 10 via a gasket 12, and is integrated with the lower frame 3 by bolts 13.

On the outward bent part 14 of the upper part of the cathode 4, the outward flange 17 of the lower end of the fluidized particle diffusion prevention tower 16 is mounted via the gasket 15, and the bolt 1
8. Fluidized particle diffusion prevention tower 1
6, in order from the bottom, the lower end outward flange 17;
It is composed of a small diameter part 19, a tapered part 20, a large diameter part 21, and an upper end outward flange 22. A disk-shaped cover body 23 is mounted on the outward flange 22.
It is tightened by 4. A cylindrical anode 26 whose lower end reaches the vicinity of the recess 8 is vertically disposed at the center of the lower surface of the lid body 23 via a rod-shaped body 25.
6 has a large number of holes 27 for venting gas. A cylindrical diaphragm 28 made of a material substantially impermeable to the electrode liquid, such as polytetrafluoroethylene, and having an open top surface is attached to the lower and side surfaces of the anode 26 in close contact with the upper end of the diaphragm 28. It is fixed to the anode 26 with a ring 29.
Cathode particles 30 are accommodated in a fluid state in the electrolytic cell body 1 outside the diaphragm 28 . Reference numeral 31 indicates an electrolytic solution outlet connected to the side surface of the large diameter portion 21 of the fluidized particle diffusion prevention tower 16, 32 indicates a generated gas outlet connected to the upper surface of the lid body 23, and 33 indicates a lower side surface of the cathode. This is the cathode particle outlet provided in the

Next, the procedure for electrolyzing a liquid to be electrolyzed using the electrolytic cell having the above-mentioned structure will be explained by taking metal recovery as an example.

A metal-containing solution such as metal-containing waste liquid is supplied to the electrolytic cell body 1 from a solution supply port 2. This solution is
Generally, an aqueous solution is used, but an organic solution such as alcohol used in solvent extraction may also be used. The supplied solution is distributed between the pores of the lower diaphragm 7 and the solution distribution plate 1.
0 into the cathode chamber under pressure. In this case, the solution serves to maintain the cathode particles 30 in a fluid state. The cross-sectional area of the solution that has passed between the cathode particles 30 increases at the tapered portion 20, and the flow rate of the solution is reduced, so that the cathode particles 30 and the solution are separated, and a uniform laminar flow is obtained in the cathode particles. The metal ions in the solution are electrolytically reduced on the cathode particles 30, become metal atoms and precipitate on the cathode particles 30, and water is decomposed as a side reaction to generate hydrogen. 32
taken from. Furthermore, oxygen is generated on the surface of the anode 26 due to a normal water electrolysis reaction. This oxygen is generated from the entire surface of the anode 26, but the diaphragm 28
The oxygen generated between the anode 26 and the anode 26 is extracted from the hole 27 of the anode 26 to the back side of the anode 26, and is taken out from the generated gas outlet 32 through the hole on the upper surface of the anode 26. The generated gas does not exist between the diaphragm and the anode to increase the electrolytic voltage, cause the diaphragm to wave, destabilize the electrolytic conditions, or damage the diaphragm. The electrolyzed solution whose metal ion concentration has been reduced overflows from the electrolytic solution outlet 31 and is taken out of the electrolytic cell.

As the electrolysis progresses, metal is deposited on the cathode particles 30. As the amount of precipitation increases, the cathode particles 3
The particles 30 become heavier and gather in the lower part of the cathode chamber, and the cathode particles 30, which are precipitated in a relatively small amount, are present in the upper part of the cathode chamber. The cathode particles 30 where the metal has sufficiently precipitated and gathered in the lower part of the cathode chamber are taken out of the electrolytic cell from the cathode particle outlet 33, and cathode particles corresponding to the amount taken out are supplied from above to the cathode chamber. This results in
The cathode particles can be supplied and taken out without stopping the operation, and continuous operation over a long period of time is possible.

In this electrolytic operation, in order to efficiently impart a cathode potential to the fine particles in the fluidized bed and deposit the metal on the cathode with high current efficiency and low electrolytic voltage, it is desirable to perform electrolysis under the following electrolytic conditions. .

Cathode current density: 30A/ ^dm2 or less (preferably
10A/dm ² or less) Anode current density: 20A/dm ² or less (preferably
5A/dm ² or less) Current concentration in fluidized bed: 30A/- fluidized bed or less (preferably 10A/- fluidized bed or less) Fluidized bed void ratio: 40 to 90% (preferably 60 to 75%) Here, cathode current If the density and the anode current density exceed 30 A/dm ² and 20 A/dm ² , respectively, the voltage will become unnecessarily high, which is not preferable. Furthermore, when the current concentration in the fluidized bed exceeds 30A/- fluidized bed, not only does the voltage increase, but plugging occurs, and when the fluidized bed void ratio exceeds 90%, the voltage increases, and when it falls below 40%, the solution supply Since plugging occurs near the mouth, it is best to keep it within the above range.

Furthermore, if this electrolytic operation is continued, the diameter of the cathode particles will increase as the metal is deposited, and the fluidization conditions (fluidized bed height, fluidized bed void ratio, fluidized bed pressure loss) will change, so this The fluidized bed section of the tank is preferably designed as follows. That is, the height of the fluidized bed is at least 1.2 times, preferably at least 1.4 times, the height of the initial fluidized bed, and the cross-sectional area of the fluidized particle scattering prevention tower is at least 1.5 times, preferably at least twice, the cross-sectional area of the electrolytic cell body. As a result, the cathode particles can be maintained in a fluid state and the particles can be prevented from escaping. In this way, up to twice the original diameter of the cathode particles,
Metals can be deposited.

FIG. 3 is a longitudinal sectional view showing a second embodiment of the invention. This electrolytic cell is an improvement of the electrolytic cell of the first embodiment, and the same members as those of the first embodiment are given the same reference numerals and explanations thereof will be omitted.

The electrolytic cell main body 1' consists of a cylindrical body with an open upper surface and an outward flange 41 connected to the upper end.A cathode supporting cylinder 42 is provided near the lower end of the inner wall of the main body 1'.
is installed inside the cylinder 42, and a porous diaphragm 43 is provided on the cylinder 42.
A donut-shaped cathode lower frame 45 having a lattice-shaped support piece 44 installed therein is placed therebetween. A porous cylindrical cathode 4' is erected on the upper edge of the lower cathode frame 45 by welding or the like, and a solution dispersion plate 10' is placed on the inner edge of the lower cathode frame 45.

The upper end of the cathode 4' has an outwardly bent portion 46 at the upper end.
A short cylindrical cathode upper frame 47 in which
The lower ends of the two are connected by welding or the like, and the outer end of the outward bent portion 46 is aligned with the outer end of the outward flange 41.

A perforated diaphragm 28' made of nylon or the like is tightly attached to the bottom and side surfaces of the anode 26, and does not allow the cathode particles to pass through, but allows the electrolyte to pass through relatively freely. A large number of particles 48 made of beads and the like are accommodated.

When a metal-containing solution is supplied to this electrolytic cell from the solution supply port 2, metals are recovered in the same manner as in the first embodiment. In addition, in this electrolytic cell, the solution is supplied under pressure to the cathode chamber, and the diaphragm separating the anode chamber and the cathode chamber is porous, so if particles are not present in the anode chamber, the electrolyte The metal moves from the cathode chamber to the anode chamber, passes through the anode chamber with low resistance, and is taken out of the electrolytic cell without coming into contact with the cathode particles. Although the metal is not recovered, the large number of particles present in the anode chamber As a result, the resistance increases and the flow of the electrolyte in the anode chamber is inhibited, so that the electrolyte comes into sufficient contact with the cathode particles and the metal is recovered at a high yield.

Example 1 Gold was recovered from gold plating waste liquid using the fluidized bed electrolytic cell shown in FIG. The dimensions of each part of the electrolytic cell are: height of the electrolytic cell body: 113.5cm, inner diameter: 14.0cm,
The height of the porous anode was 105 cm and the diameter was 4.9 cm, the height of the fluidized particle diffusion prevention tower was 35 cm, and the outer diameter of the large diameter part was 21 cm.

The materials of each part are acrylic resin for the electrolytic cell body and fluidized particle diffusion prevention tower, platinum-coated titanium for the anode, gold-plated graphite particles with a particle size of 0.1 to 0.15 mm for the cathode, and polytetrafluoroethylene for the diaphragm. A non-porous membrane and a solution dispersion plate made of vinyl chloride resin were used.

The test solution had a pH value of 4.1, a total organic carbon content (TOC) of 15.0 g/, a silicon dioxide content of 56 mg/,
The total phosphorus amount was 1.6 mg/, and the following ion concentrations were used, and the total concentration was adjusted to 1650 ppm by diluting with water before supplying to the electrolytic cell.

Au 2580ppm Ni 25ppm Na 51ppm K 13300ppm CN ^- 1000ppm SO ₄ ^3- 43000ppm Cl ^- 530ppm This adjusted gold waste solution was supplied to the electrolytic cell at a flow rate of about 2.8/mm, and the anode current density was 2.60A/dm ² and the cathode current density was 1.0A/dm ² , current concentration in the fluidized bed 10.7A/
-When electrolysis was carried out under the conditions of fluidized bed and fluidized bed void ratio of cathode particles of 70%, the electrolysis voltage was 2.1 to 2.5V,
The average current efficiency was 38%, and the gold concentration at the electrolyte exit was 3 ppm. Note that the nickel concentration did not decrease.

Example 2 The same electrolytic cell as in Example 1 was used, except that a nylon net with a pore size of about 50 μm was used as the diaphragm, and a large number of glass beads with a particle size of about 0.3 to 0.6 mm were housed in the anode chamber. Gold plating was applied to copper particles (spherical particles with an average particle size of 100 μm) by the following method.

First, 5 kg of copper particles were degreased, then washed with water, pickled, and washed with water to remove dirt and oxides from the surface of the copper particles, and then electroplated with gold under the following conditions.

Gold plating conditions Plating liquid: Auclonex C (cyan plating liquid made by Japan Electroplating Engineers Co., Ltd.) containing 3 g of gold Impurities: 40 ppm copper Plating liquid amount: 50 Current: 45 A Voltage: 4 V Plating temperature: 50℃ Plating time: 60 minutes Flow rate: 0.3cm/sec The entire copper particle turned golden in about 10 minutes.

After gold plating, the plating solution was removed, thoroughly washed with water, filtered, and dried to obtain particles (Au/Cu particles) in which the copper particles were coated with a gold plating film of 0.1μ.

Regarding the Au/Cu particles obtained by the method described above,
As a result of examining the gold distribution image using SEM photographs and an X-ray microanalyzer, it was found that gold was uniformly electrodeposited on the copper particles. In addition, copper as an impurity remained at 40 ppm even after plating.

The Au/Cu particles obtained in this way could be used as a material for electrical contacts.

Example 3 Using Al ₂ O ₃ particles 2 with an average particle diameter of 1 mm, plating was performed by the following method.

First, the Al ₂ O ₃ particles were degreased, then washed with water, pickled, and washed with water, and then chemically plated with nickel according to the following steps.

Sensitizing: Stannous chloride solution 2 ↓ Water washing ↓ Actipation: Palladium chloride solution 2 ↓ Water washing ↓ Chemical nickel plating: Uemura Kogyo Co., Ltd. BEL Nickel 5 (reducing agent dimethyl porazan) ↓ Water washing Next, the Al ₂ O ₃ particles were subjected to electroplating using an apparatus as shown in FIG. 3 under the following conditions according to Example 2.

Platinum plating conditions Plating liquid: 10g of chloroplatinic acid/Hydrochloric acid 0.3N Plating liquid volume: 50 Current: 200A Voltage: 20V Plating temperature: 20℃ Plating time: 60 minutes Flow rate: 0.2cm/sec As mentioned above All of the Pt/Ni/Al ₂ O ₃ particles obtained by this method have a uniform electroplated film, and the particles reliably contact the plating solution, which is the cathode, to form a uniform layer. The inventors have discovered that it is possible to obtain electrodeposited materials.

In addition, if the particles are non-conductive, it is necessary to apply chemical plating before electroplating, but in the present invention, when chemical plating is applied to particles, the film thickness is such that electroplating is possible. Compared to the case where highly conductive particles are obtained only by chemical plating, the film thickness can be made thinner, and the cost can be significantly reduced.

Example 4 In the electrolytic cell of Example 1, the anode, the cathode, and the cathode particles were respectively used as the cathode, the anode, and the anode particles, the anode particles were graphite particles with a particle size of 0.4 to 0.8 mm, and the cathode was made of gold coated titanium. Cyanide ions in waste liquid were decomposed.

The same waste liquid as in Example 1 was used as the test waste liquid, and the free cyanide ion concentration was adjusted to 640 ppm by diluting the water before supplying it to the electrolytic cell.

This adjusted waste liquid was supplied to the electrolytic cell at a flow rate of approximately 2.8/mm, and the anode current density was 2.60A/dm ² , the cathode current density was 1.0A/dm ² , and the current density in the fluidized bed was 10.7A/dm 2 .
-Fluidized bed, fluidized bed void ratio of graphite particles 70%
When electrolyzed under the following conditions, the electrolytic voltage was 2.1~
The voltage was 2.5V, the average current efficiency was 85%, and the free cyanide ion concentration at the electrolyzer outlet was 80ppm.

〔Effect of the invention〕

The present invention uses a fluidized bed electrolytic cell to greatly increase the surface area of the main electrode when recovering metals from solutions, refining metals, plating particles, or decomposing organic compounds in solutions. Because it is large, it allows efficient electrolysis at low current density, and
Since the cross-sectional area of the upper part of the main electrode chamber is gradually increased, the flow velocity of the electrolyte decreases in the upper part of the electrode chamber, and the main electrode particles that rise with the electrolyte are electrolyzed from the electrolyte outlet at the upper part of the main electrode chamber. Since the auxiliary electrode is porous and tightly attached to the diaphragm, the gas generated by the auxiliary electrode is discharged to the back of the auxiliary electrode, so there is no space between the auxiliary electrode and the diaphragm. There is no gas ingress, no increase in electrolytic voltage, no uneven current distribution, and no damage to the diaphragm.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway front view showing a first embodiment of the present invention, Fig. 2 is a cross-sectional view taken along the - line in Fig. 1, and Fig. 3 is a longitudinal cross-section showing a second embodiment of the invention. It is a diagram. 1, 1... Electrolytic cell body, 4, 4'... Cathode, 1
6... Fluidized particle diffusion prevention tower, 26... Anode, 27
...pore, 28,28'...diaphragm, 30...cathode particle.

Claims (1)

[Claims] 1. Main electrode particles are accommodated in the main electrode chamber of the electrolytic cell body, which is divided into a main electrode chamber and an auxiliary electrode chamber by a diaphragm, and an electrolytic solution is supplied to the main electrode chamber to flow the main electrode particles. In this method, the flow velocity of the upward flow of electrolyte solution is reduced in the upper part of the main electrode chamber, the main electrode particles accompanying the upward flow are separated from the upward flow, and the main electrode particles flow out to the outside. An electrolysis method using a fluidized bed, which is characterized in that a porous auxiliary electrode is brought into close contact with a diaphragm, and gas generated on the surface of the auxiliary electrode is discharged to the back of the auxiliary electrode while electrolysis is carried out. 2. The electrolysis method using a fluidized bed according to claim 1, wherein the main electrode chamber is either a cathode chamber or an anode chamber, and the auxiliary electrode chamber is a counter electrode chamber to the main electrode chamber. 3. In an electrolytic cell containing main electrode particles in the main electrode chamber of a cylindrical electrolytic cell divided into a main electrode chamber and an auxiliary electrode chamber by a diaphragm, an electrolyte supply port is provided at the bottom of the main electrode chamber, and the main electrode chamber A fluidized particle dispersion prevention tower whose cross-sectional area gradually increases toward the top is installed at the top of the tower, an electrolyte outlet is provided on the wall of the fluidized particle dispersion prevention tower, and a porous auxiliary electrode is installed in the diaphragm. An electrolytic cell using a fluidized bed characterized by close contact.