JPS6241973Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a vertical aqueous electrolytic cell equipped with an ion exchange membrane.

Conventional methods for electrolyzing aqueous solutions of alkali metal chlorides (eg, common salt) include a mercury method, a diaphragm method, and an ion exchange membrane method. The mercury method produces a product with a high concentration of caustic alkali and high purity, but in recent years it has been replaced by the diaphragm method because of the possibility of mercury leaking and causing environmental pollution problems. However, in the diaphragm method, the concentration of the caustic alkali produced is as low as about 9 to 12%, and it also contains a considerable amount of alkali metal chloride as an impurity. Therefore, depending on the intended use of the product, further purification or concentration may be required. In consideration of the drawbacks of these diaphragm methods, methods using cation exchange membranes are being developed, and as the electrolytic cell for this purpose, for example, a filter press type is generally employed.

However, when adopting the ion exchange membrane method instead of the conventionally used diaphragm method, it is uneconomical to manufacture a new electrolytic cell, and there has been a strong demand for repurposing the electrolytic cell for the diaphragm method.

There are vertical and horizontal types of electrolytic cells for the diaphragm method, and the present invention relates to improvements to vertical electrolytic cells. The asbestos diaphragm of an electrolytic cell for the diaphragm method is made by depositing asbestos from an asbestos slurry onto a cathode wire mesh, but it is impossible to immediately install a cation exchange membrane in place of this asbestos diaphragm, and a cation exchange membrane installation device is required. becomes a problem.

Therefore, the present invention aims to convert the conventional vertical aqueous electrolyzer for the diaphragm method to the ion exchange membrane method, and was completed as a result of intensive research.

That is, the present invention provides a cathode with a side plate that maintains a space above the cathode wire mesh and surrounds the upper part of the cathode wire mesh in a vertical aqueous electrolytic cell in which an anode plate and a box-shaped cathode wire mesh surrounding the anode plate are arranged. It has a cover and a hole at the bottom through which the anode rod passes, and a vertical side plate surrounding the lower part of the anode plate, and is watertightly clamped and fixed by a flange provided on the anode rod and an anode mounting plate surface. The mounting member is provided parallel to each vertical plane of the anode and covers the anode, and the surface facing the anode is perforated, the upper side is airtightly attached to the side plate of the cathode cover, and the lower side is attached to the vertical side plate of the mounting member This invention relates to a vertical aqueous electrolytic cell that is provided with a tubular frame that is watertightly attached and a cation exchange membrane that is fixed to the anode side of the frame in an airtight and watertight manner so as to completely cover the perforated part of the frame.

In this specification, airtightness and watertightness refer to a state in which the flow of gas and liquid between the cathode area (cathode chamber) and the anode area (anode chamber) is virtually blocked.

Next, Figure 1A shows a typical example of the present invention.
B. The present invention will be explained based on FIGS. 2 and 3.

Figures 1A and 1B show the configuration of the electrolytic cell of the present invention. 'longitudinal section). In the figure, 1 is a box-shaped cathode wire mesh, 2 is an anode plate, and 3 is a cathode cover. The cathode cover 3 is provided with a space 4 held above the box-shaped cathode wire mesh 1. It has a large volume for collecting generated hydrogen gas. The box-shaped cathode wire mesh is shown in Figure 1a,
As shown in b, it is box-shaped and surrounds the anode plate. 5 is an anode mounting plate, 6 is a sheet packing provided thereon, and an anode rod 7 penetrates and is embedded in the anode plate 2 and is attached thereto. Reference numeral 8 denotes a mounting member having a hole provided on the center line of the bottom, and is fixed via a packing 6 between a collar 16 provided on the anode rod 7 and the anode mounting plate 5. Further, 9 is a side plate of the cathode cover 3;
and a vertical side plate 9' around the mounting member 8.
A tubular frame A is provided between the side plate 9 and the side plate 9 so as to be parallel to the vertical plane of the anode and cover the anode, and only the portion facing the anode has a perforated structure such as a grid. and is attached airtightly and watertightly to the vertical side plate 9'. Reference numeral 10 denotes a tubular cation exchange membrane, which completely covers the frame A from the anode side and is fixed airtightly and watertightly at the upper and lower portions of the tubular frame A. In this case, it is convenient for the ion exchange membrane to use a tubular body with a size that can surround the cathode, since there are no membrane joints. Furthermore, since the ion exchange membrane covers the anode side of the perforated portion of the tubular frame, it has the effect of being pushed by water pressure from the anode side where the water level is higher and being fixed to the surface of the tubular frame A.

With this structure, the anode chamber and the cathode chamber are completely watertightly and airtightly separated by the ion exchange membrane. The structure of the cation exchange membrane 10 and the tubular frame A is not limited as long as they are in close contact to fix the cation exchange membrane 10.
The details of a typical example are shown in FIG. In FIG. 2, a frame A is provided at the edge of the side plate 9 and the vertical side plate 9', and a cation exchange membrane 10 is arranged on the anode side of the frame A, and a holding plate 12, 12', 13, 13', bolts 14, 14', and nuts 15, 15' are tightened and fixed airtightly and watertightly. Also second
In the figure, a collar 16 is provided on the anode rod 7, and a mounting member 8 is fixed between the collar 16 and the anode mounting plate 5 via packings 6 and 17.

FIG. 3 is a perspective view showing the assembly structure of the anode plate 2, anode rod 7, and mounting member 8.

In the electrolytic cell of the present invention, the anode chamber and the cathode chamber are completely separated by a cation exchange membrane, similar to the conventional electrolytic cell for ion exchange membrane method, and the amount of alkali metal chloride in the produced caustic alkaline solution is Very few. In addition, in the cathode chamber, there is a large space for hydrogen collection between the box-shaped cathode wire mesh and the cathode cover.
Since the anode plate 2 is completely immersed in the electrolyte, the entire electrolytic surface of the anode plate 2 can be effectively utilized.
In addition, the ion exchange membrane has good fixation and electrolysis can be carried out stably. Note that chlorine is generated from the anode chamber, so
It is necessary to use a corrosion-resistant material such as titanium, titanium alloy, or fluororesin for the exposed parts such as the presser plate.

Assembly of this device is easy. An example is shown below.

First, a box-shaped cathode wire mesh is attached to the electrolytic cell body.

Next, as shown in FIG. 2, a presser plate 13 and a nut 15 are fixed to the lower end of the side plate 9 of the cathode cover 3 by, for example, welding. A common through hole is provided in the side plate 9 and the holding plate 13 to match the hole in the nut 15.

Separately, as shown in FIG. 2, attach the lower end of the tubular frame A and the lower end of the cation exchange membrane to the vertical side plate 9' of the mounting member 8 with holding plates 12', 13', nuts 15',
It is fixed with bolts 14'. As a result, the tubular frame A and the cation exchange membrane 1 are attached to the mounting member 8.
0 is attached to obtain an integrated structure.
The mounting member 8 of this integrated structure is placed on the mounting plate 5 via sheet packing so that its perforation matches the hole in the anode mounting plate 5.

Next, after inserting the anode rod 7 of the anode plate 2 into the mounting member 8 and the hole in the anode mounting plate 5, the flange 16 of the rod is inserted into the packing 17 as shown in FIG.
It is fixed to the anode mounting plate 5 via known means.

Finally, a second
As shown in the figure, a cathode cover 9 has a holding plate 12 fixed to the ion exchange membrane 10 side through packing, and a holding plate 13 and a nut 15 fixed to the annular frame A side.
is held so that all the holes communicate with each other, and then the bolt 14 is inserted into the communication hole from the holding plate 12 side, that is, from the anode chamber side, and screwed into the nut 15. Thereby, the cathode cover 3 is fixed to the tubular frame A and the ion exchange membrane at the side plate 9 in a watertight and airtight manner.

Note that in the present invention, the anode plate is fixed to the mounting member and the anode mounting plate before the cathode cover and the integrated structure are fixed, but it is fixed after the cover and the integrated structure are fixed. You can.

The other end of the anode cover is sandwiched between the side wall of the electrolytic cell and the electrolytic cell lid, as shown in FIG. 1B, and fixed airtightly and watertightly.

[Brief explanation of the drawing]

Figure 1A is a partial plan view showing the structure of the electrolytic cell of the present invention, Figure 1B is a partial vertical cross-sectional perspective view, and Figure 2 is the connection of the cathode cover, mounting members, frame, and cation exchange membrane. FIG. 3 is a perspective view showing an assembly structure of an anode plate, an anode rod, and a mounting member. Explain the main symbols. 1...Box-shaped cathode wire mesh,
2...Anode plate, 3...Cathode cover, 4...Space between the cathode and cathode cover, 8...Mounting member, 9...
...Side plate of cathode cover, 9'...Vertical side plate of mounting member 8, 10...Cation exchange membrane, A...Tubular frame.

Claims (1)

[Scope of Claim for Utility Model Registration] (a) In a vertical aqueous electrolytic cell in which an anode plate and a box-shaped cathode wire mesh surrounding the anode plate are arranged, (b) a space above the cathode wire mesh is maintained so that the cathode (c) a cathode cover with a side plate that surrounds the upper part of the wire mesh, and (c) a vertical side plate that has a hole through which the anode rod passes and surrounds the lower part of the anode plate, and a collar provided on the anode rod and the anode. (d) a mounting member that is watertightly clamped and fixed by the mounting plate surface; (e) A tubular frame whose lower side is airtightly and watertightly attached to the vertical side plate of the mounting member; A vertical aqueous electrolytic cell characterized by being provided with a cation exchange membrane.