JPS6157396B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to improvements in electrolyzers.

[Conventional technology]

As shown in FIG. 1, the conventional electrolytic apparatus connects an anode lead wire 6 from a DC power source 5 to an electrolytic cell 4 in which an anode 1 and a cathode 2 having a certain effective area are immersed in an electrolytic solution 3 to be treated. When electricity is supplied through the cathode lead wire 7, the anode 1 and the cathode 2 in the electrolyte 3 to be treated are
Electrolysis occurs in the effective area of , and the target reaction component contained in the electrolyte 3 to be treated is treated by oxidation or reduction electrode reaction.

2 to 5 show the basic configuration of a conventional electrolytic device based on the principle shown in FIG. and 3b are electrolyzed between an anode 1a or 1b having a certain effective area and a cathode 2a or 2b.

4 is a cross-sheet type electrolyzer in which an anode 1c and a cathode 2c are separated by an insulating cloth 8, and the electrolyte 3c to be treated flows as indicated by the arrow in the figure. Note that, normally, the flow also flows from a part of the mesh that flows parallel to the cross-sheet electrode.

Furthermore, the one in Figure 5 is intended to significantly increase the electrode surface area, and the main anode 1d
The dispersion type electrode group 9 is composed of bipolar fine particles between the main cathode 2d and the electrolyte solution 3d. There is significant turbulence in the flow of the treated electrolyte 3d. This electrode reaction is explained by the dispersion electrode group 9
Each particle is polarized with positive and negative polarity.

Note that in the conventional electrolyzer described above, the anode 1
The polarity of cathode 2 can be reversed, and the polarity of anode 1 can be reversed.
In some cases, a diaphragm is provided between the cathode 2 and the cathode 2, and the electrode shapes are various based on the principle shown in FIG.

[Problem that the invention seeks to solve]

However, the conventional electrolytic apparatus has the following essential drawbacks even when a single electrolytic cell or a plurality of electrolytic cells are connected separately outside the system.

That is, even if the concentration of the target reaction component in the electrolytic solution 3 to be treated changes as the electrolysis time changes, electrolysis is carried out with the electrolytic conditions being the same at the initial stage of setting, so the concentration of the target reaction component at the end of the treatment decreases. When this happens, performance deteriorates significantly due to causes such as generation of loss current or insufficient applied current density to suppress side reactions. Theoretically, when the concentration of the target reaction component decreases, the limiting current density becomes smaller, so the electrolysis time required to treat the concentration of the symmetric reaction component in the electrolytic solution 3 to a certain value becomes significantly longer, and the loss current increases. . Therefore, the application of electrolytic methods using conventional electrolyzers has been limited compared to other physical processing methods.

As a result of intensive research aimed at improving these drawbacks, the present invention has discovered an electrolytic device that can perform treatment with higher performance. In addition, the present invention is characterized in that the effective area of the electrodes facing each other is changed along the flow of the electrolyte to be treated in an electrolytic apparatus for performing electrolytic treatment.

[Means for solving problems]

That is, the electrolytic device of the present invention has (1) a plurality of electrodes each having a different effective electrode area assembled in a single tank.

(2) In all electrolyzer systems, the electrolyte to be treated 3
This allows processing to be performed by changing the current density according to changes in the concentration of target reaction components.

(3) The convection time of the electrolyte to be treated varies depending on the electrode configuration.

(4) It is also equipped with a means that allows the flow direction of the electrolyte to be treated to flow from high current density to low current density, or vice versa, from low current density to high current density, depending on the content of the electrode reaction.

It is.

[Effect]

According to the present invention, the effective area of the electrode is increased and the volume of each electrolytic chamber is also increased. Therefore, as the target reaction component in the electrolyte to be treated decreases, the electrode area becomes larger, i.e., the current density becomes smaller. Moreover, it is processed with a long residence time. As a result, the yield and electrode efficiency at the final stage of treatment are improved.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

Example 1 An electrolysis device according to Example 1 will be described with reference to FIGS. 6, 7, 13, and 14. however,
Fig. 6 is a perspective view of the electrolyzer, Fig. 7 is a cross-sectional view taken along the line A-A in Fig. 6, Fig. 13 is a partially enlarged sectional view of Fig. 6, and Fig. 14 is a cross-sectional view of Fig. 6. FIG.

4a in the figure is a cylindrical tank. This tank 4a
An inlet water pipe 10a for the electrolyte to be treated is provided at the center of the upper and lower sides. A large number of communication holes 10' are provided in the side wall of this water pipe 10a.
At the top of the tank 4a, an upper lid 11a is provided, which includes a flow opening 12a through which the electrolyte to be treated flows, a gas vent 15a, and an anode current-carrying end 16a made of Ti material. This upper lid 11a closes the opening of the tank 4a. A saucer 13a having a collecting pipe 14a for receiving and discharging the electrolyte to be treated is provided around the upper lid 11a. A cathode current-carrying end 17a connected to a cathode of a partition wall described later is provided at the center of the periphery of the tank 4a.

Inside the tank 4a, there is a header 18 made of Ti material that concentrically surrounds the water pipe 10a and partitions the tank 4a.
a is stored. An anode 1a is arranged in a ring shape on the outer peripheral surface of the header 18a.
Further, a cathode 2a is arranged in a ring shape on the inner peripheral surface of the tank 4a facing the anode 1a.
A flow opening 1 is provided at the bottom of the header 18a.
2a is provided. The anode 1a and the cathode 2a
A plurality of cylindrical bipolar electrodes 19a are provided between them. These bipolar electrodes 19a include a frame 191 having a flow opening 12a, and a frame ₁₉₁ having a flow opening 12a.
₁ and a gas- and liquid-impermeable bipolar electrode working part ₁₉₂ provided at the center of the electrode. Here, the header 18a and the bipolar electrode 19a...
has the function of a fulcrum of the electrode and a compartment. Drain pipes 20a are provided at the bottoms of the compartments formed by the bipolar electrodes 19a, etc., respectively. Note that 22 in the figure indicates a portion between the electrodes.

In an apparatus having such a structure, a flow of the electrolyte to be treated is supplied from the water pipe 10a according to the processing purpose, meandering up and down inside the tank 4a partitioned by the header 18a and the bipolar electrode 19a, and the flow of the electrolyte in the tank 4a is There are two methods: one is to take it out from the opening 12a, and the other is to let it flow and take it out from the water pipe 10a. At this time, when the electrolyte to be treated flows from the upper part of the water pipe 10a, the lower side of the water pipe 10a is blocked, and conversely, when the electrolyte to be treated flows from the lower part, the upper side of the water pipe 10 is blocked. 13th
The figure shows one example, in which the electrolyte to be treated flows from the lower part of the water pipe 10a. Moreover, the current flow can be selectively used in two ways depending on the capacity, in which the current density increases in accordance with the flow direction of the electrolyte to be treated. However, if the above-described flow and energization are reversed to the explanation in FIG. 6, the water pipe 10a in FIG.
Alternatively, it may be operated by a valve in the subsequent flow line of the collecting pipe 14a. Furthermore, it goes without saying that the energization method is also a combination of electrodes that is opposite to that described in FIG.

That is, the electrolyzer according to the first embodiment mainly includes a cylindrical tank 4a, an inlet water pipe 10a provided along the axial direction in the center of the tank 4a and having a large number of flow holes 10', and the tank 4a. A top lid 11a provided on the upper part of the tank 4a and equipped with an anode current-carrying end 16a, a header 18a housed in the tank 4a and concentrically surrounding the water pipe 10a to partition the tank 4a, and an outer peripheral surface of the header 18a. an anode 1a arranged in a ring shape, a cathode 2a arranged in a ring shape on the inner peripheral surface of the tank 4a facing the anode 1a, and a bipolar structure arranged in the center between the anode 1a and the cathode 2a. It has a structure composed of a plurality of cylindrical bipolar electrodes 19a serving as an electrode action part ₁₉₂ .

Example 2 FIG. 8, FIG. 9, and FIG. 10 each show an electrolysis device according to Example 2. That is, FIG. 8 is a perspective view of a box-shaped electrolytic device that is the same as the electrolytic device shown in FIG. 6 described above. FIG. 9 is a cross-sectional view taken along line BB in FIG. 8. FIG. 10 is a longitudinal sectional view taken along line CC in FIG. 9. In addition, 4 in Figures 8 to 10
b, 10b to 20b are Fig. 6, Fig. 7, Fig. 13
They correspond to 4a and 10a to 20a in the figure and FIG. 14, respectively.

Embodiment 3 FIG. 11 is a longitudinal cross-sectional view of the main parts of an electrolysis device according to Embodiment 3 of the present invention, and shows an example in which the electrode portion is different from FIGS. 10 and 14. That is, a header 18c made of Ti material and having a flow opening 12c at the bottom and an anode 1c that also functions as a current-carrying end.
are connected by a connecting terminal 21c, and in the next electrode, a cathode 2c and an anode 1c are connected by a connecting terminal 21c, and the following electrodes are similar in that they are different from each other, and the other configurations are as shown in FIGS. This is the same electrolysis device as explained in the figure. In addition, in FIG. 11, 1c, 2c, 12c to 14c, 17c to 20
c are respectively 1b, 2b, 12b ~ in FIG.
14b, 17b to 20b.

The electrolytic devices according to Examples 1 to 3 described above have the following functions and effects. That is, in the electrolytic apparatus of the present invention, the electrolytic solution to be treated enters from the header 18a (or 18b, 18c) in the center of the electrolytic apparatus, passes through each electrolytic chamber in series, flows outward, and flows into the collecting pipe 14a ( or 14b, 14c)
When the current is passed in the same direction as the electrolyte to be treated, the effective area of the electrode increases at each stage and the volume of each electrolytic chamber increases, so the target reaction component in the electrolyte to be treated increases. As the current density decreases, the electrode area is correspondingly increased, ie, the current density is reduced and the convection time is increased. As a result, the yield and current efficiency at the final stage of treatment are improved.

In addition, in the flow of the electrolyte to be treated, depending on the water quality of the electrolyte to be treated, only energization may be performed, or the outermost cathode 2a (or 2b, 2c) may be replaced with the anode 1a (or 1b, 1c), or the outermost cathode 2a (or 2b, 2c) may be replaced with the anode 1a (or 1b, 1c). It is also possible to use the inner anode as the cathode and flow it outward. In that case, it will theoretically have the same effect as above, or it will correspond to the outermost current density and the cleaning of the electrolyte to be treated. It is effective in that it can be selected arbitrarily.

In addition, the electrolyte to be treated is passed through the collecting pipe, passes through each electrolytic chamber, and flows to the lower water passage pipe of the header in the center of the electrolyzer, and the current is passed in the opposite direction to the flow of the electrolyte to be treated, that is, from the anode current-carrying end. By flowing, the target reaction component in the electrolyte to be treated is reduced by electrode reaction, and when producing the desired product, it prevents loss reactions that tend to occur as the concentration of the product increases. This can be significantly suppressed by increasing the current density, so the target reaction component in the electrolyte to be treated decreases and the product increases, i.e. the header 18 at the center where the effective area of the electrode is smallest.
High yield and current efficiency can be obtained by supplying current from a (or 18b, 18c).

As described above, in the flow of the electrolyte to be treated, the key point of the electrolytic device of the present invention is that it is based on the principle of changing the current density according to the target reaction component, and the energization method can be arbitrarily selected as long as it follows this principle. I can do it.

Next, using the electrolysis device of the present invention, Ti was used as an electrode material.
Using a plated with Pt, the product concentration and COD concentration were measured by the current density and current concentration as shown in the table below. The result is the 12th
As shown in the figure.

Table Current Density (A/dm ² ) 8←→48 Current Density (A/) 3 to 18 As is clear from Figure 12, (1) When producing a target substance as a product at a high concentration by electrolytic oxidation, the present invention The electrolyzer was superior to conventional electrolyzers, and a significant improvement in performance was observed.

(2) Regarding the treatment of COD in wastewater, the device of the present invention was shown to have significantly higher performance than the conventional device.

〔Effect of the invention〕

As detailed above, the present invention provides a high-performance electrolyzer that is extremely useful in the fields of seawater and salt water electrolysis, soda electrolysis, wastewater treatment, and other fields of electrolytic separation, generation, and electrolytic synthesis. Can be provided.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the principle of a conventional electrolytic device, FIGS. 2 to 5 are basic configuration diagrams of a conventional electrolytic device, FIG. 6 is a perspective view of an electrolytic device according to Embodiment 1 of the present invention, and FIG. Figure 7 is a cross-sectional view taken along line A-A in Figure 6;
FIG. 8 is a perspective view of an electrolysis device according to Example 2 of the present invention, FIG. 9 is a cross-sectional view taken along line B-B in FIG. 8,
FIG. 10 is a vertical cross-sectional view taken along the line C-C in FIG. 9, FIG. 11 is a vertical cross-sectional view of the main parts of the electrolyzer according to Example 3 of the present invention, and FIG. 12 is a cross-sectional view of the current concentration, COD concentration, and A curve diagram showing the relationship with product concentration, FIG. 13 is a partial enlarged sectional view of FIG. 6, and FIG. 14 is a partial longitudinal sectional view of FIG. 6. 1, 1a, 1b, 1c... Anode, 2, 2a, 2
b, 2c... cathode, 3, 3a, 3b, 3c... electrolyte to be treated, 4a... tank, 10a, 10b... inlet water pipe, 10'... distribution hole, 11a, 11b...
...Top lid, 12a, 12b, 12c...Flow opening, 13a, 13b, 13c...Saucer, 14a,
14b, 14c...collecting pipe, 15a, 15b...
Gas venting, 16a, 16b...Anode current carrying end, 17
a, 17b, 17c... cathode current-carrying end, 18a, 1
8b, 18c...header, 19a, 19b, 1
9c...bipolar electrode, 19 ₁ ...frame, ₁₉₂ ...bipolar electrode action section, 20a, 20b, 20c...drain pipe, 21c...connecting terminal.

Claims (1)

[Claims] 1. A cylindrical tank, an upper lid that closes the opening of the tank, a water pipe having a large number of flow holes provided along the axial direction in the center of the tank, and the water pipe housed in the tank. a header that concentrically surrounds and partitions the inside of the tank; an anode arranged in a ring shape on the outer peripheral surface of the header; and a cathode arranged in a ring shape on the inner peripheral surface of the tank facing the anode. , a cylindrical bipolar electrode disposed between the anode and the cathode, the center portion of which is impermeable to gas and liquid and serving as a bipolar electrode working part; Flow openings are provided alternately, and the electrolyte to be treated is supplied from the water pipe, electrolyzed while meandering up and down, and taken out from the flow opening provided in the tank, or vice versa. An electrolysis device characterized in that it is taken out from a water pipe.