JPH034626B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to mobile metal electrodes. In particular, it is an electrode in which the shape of the conductive member of the electrode is specified.

In order to reduce the electrode gap as much as possible, a movable electric member is used to connect the electrode surface and the current collector rod.
Electrodes in which the distance between a current collector rod and an electrode surface can be changed, so-called expandable electrodes, are well known, and these electrodes are often used as anodes, particularly in diaphragm electrolysis of alkali metal chlorides.

In such electrodes, the conductive member has a spring function that makes the electrode surface flexible, and at the same time
It performs a conductive function to allow electricity to flow from the current collector rod to the electrode surface. In the structure of conventional conductive members, the thickness of the member must be made thin in order to provide a spring function, but this increases the conductor resistance, and it is also necessary to increase the thickness of the member to reduce the conductor resistance. However, it required a great deal of force to close the electrode, making it difficult to satisfy both functions at the same time.

In view of the above problems, the inventors have determined that conductor resistance and
As a result of studying an electrode structure that has a small 1R loss and is movable, the inventors found that the above problem can be solved by forming the conductive member into a specific shape, and have completed the present invention.

That is, the present invention provides an electrode in which an electrode surface and a current collector rod are connected using a movable conductive member, and the distance between the current collector rod and the electrode surface can be changed. This is a movable metal electrode characterized by the presence of a thin portion.

Hereinafter, the present invention will be explained in detail based on the drawings.

1 and 2 are top views showing a conventional movable metal electrode, with FIG. 1 showing a contracted state and FIG. 2 showing an expanded state, respectively. Moreover, FIG. 3 (contracted aspect) and FIG. 4 (expanded aspect) are top views showing a typical example of the present invention.

In the figure, reference numeral 1 denotes an electrode surface, and any known material can be used without particular limitation as long as it is conductive and has corrosion resistance to the electrolyte. For example, in the case of the anode surface,
A metal such as titanium or a titanium surface coated with a noble metal such as platinum or palladium is used. Further, the shape of the electrode surface is not particularly limited, and for example, a porous material such as a mesh shape or an expanded shape may be used.

2 is a current collector rod, which has the function of conducting electrolytic current from the power source to the electrode surface 1, and is not particularly limited in material, shape, etc., as long as it has corrosion resistance to the electrolytic solution. In general, it is preferable to use a hollow bar whose inside is made of a conductive material such as copper or aluminum, and whose outer surface is coated with a material that is resistant to corrosion by the electrolytic solution, such as titanium.

3 is a conductive member, and the feature of the present invention is that the shape of the member 3 is specified. That is, the shape of the conventional conductive member 3 is as shown in FIGS. 1 and 2.
The thickness of the member 3 is uniform over the entire surface, and
In order to have a spring function as a whole, it was necessary to reduce the thickness (generally around 1.0 to 3.0 mm). Therefore, it was inevitable that the conductor resistance and 1R loss would increase.

In contrast, in the present invention, as shown in FIGS. 3 and 4, the conductive member 3 has a structure in which a portion 4 with a thinner thickness exists, so that the movability (spring) function is The conductive function can be provided mainly in the conductive part 5, and since the area of the conductive part 5 is larger than that of the thin part 4, it is possible to reduce the conductor resistance. Ta.

The material and shape of the electrically conductive member 3 are not particularly limited as long as they satisfy the above requirements, and the material is electrically conductive and corrosion resistant to the electrolyte, such as titanium, etc. Regarding the shape, if the area of the thin part 4 is too small, the mechanical strength will be reduced and it will not have the function of a spring, and the same drawbacks as the conventional one that is too large will occur, so the total area of the conductive member 3 is 5 to 30% is suitable. Further, it is preferable that the conductive member 3 having a thin portion 4 exists over the entire length of the electrode in the vertical direction as shown in FIG. Less than 1/3 of the thickness, generally
0.2 to 0.5 mm is suitable. The thickness of the conductive portion 5 at this time may be appropriately selected depending on the material, shape, etc.
Alternatively, the embodiment shown in FIGS. 3 and 4 is a shape in which an arc-shaped thin wall portion 4 is attached to a part of the conductive member 3 so as to be symmetrical left and right, and up and down, with the current collector rod 2 in between. Mobility of electrodes such as contraction and expansion (spring)
However, the shape of the conductive member 3 of the present invention is not limited to the above-mentioned shape, and may be any shape as long as it has an upper machine function. For example, as shown in FIG. 6, a plurality of thin portions 4 may be provided, and in this case, the moving distance can be reduced.

Regarding the manufacturing method of the conductive member 3 , the electric part 5
and a method of joining the thin wall portion 4 by means such as welding,
Alternatively, both may be integrally molded, and the position and structure of the member 3 may be determined by joining the current collector rod 2 and a part of the electrode surface 1 by means such as welding, and the joining position is as follows. This is determined by the shape of the electrode, etc.

In addition, there are no particular restrictions on the structure of the electrode of the present invention and the method of assembling it in an electrolytic cell. For example, when it is assembled into an electrolytic cell, the electrode is placed in a contracted state (Fig. 3) using the electrode holder 6. After installing the counter electrode between the electrodes, the electrode holder 6 is released and expanded (fourth
In addition, the present invention can be used not only as an anode but also as a cathode especially in diaphragm electrolysis.

The following examples of the present invention will be shown, but the present invention is not particularly limited to the following examples.

Example 1 An anode mesh made of titanium expanded metal coated with ruthenium oxide and a titanium-lined copper power supply rod were connected to the structure shown in FIG. 4 using a titanium conductive member.

The conductive part of the conductive member has a thickness of 3 m/m and a length of 95
m/m, and the movable part (thin wall part) has a thickness of 0.3 m/m.
They were made of titanium plates with a circumference of 10 m/m and a height of 760 m/m. Anode mesh is 400m/m x 760m/
It was set as m.

The three anodes and the bag-shaped cation exchange membrane were attached to a test electrolytic cell shown in FIG. 7, which consisted of a titanium manifold and an iron cathode mesh. The cation exchange membrane used was Neocepta C-3000 (manufactured by Tokuyama Soda Co., Ltd.).

After attaching the ion exchange membrane to the electrolytic cell, a Teflon spacer with a diameter of 3 m/m was inserted between the ion exchange membrane and the anode mesh to expand the anode and bring the cathode, spacer, exchange membrane, and anode into close contact.

A saline solution having a salt concentration of 310 g/h and a temperature of 75° C. was supplied to the electrolytic cell for 55/h, and the electrolytic cell was operated at a current load of 3.8 KA.

The electrolyzer operating temperature was 90°C, the caustic soda concentration after the cathode was 32%, and the cell voltage was 3.25V.

Comparative Example 1 In the anode structure shown in Figure 2, the conductive member is made of titanium and has a thickness of 0.5 m/m, a length of 100 m/m, and a height of
760 m/m, and the spring thickness was made uniform.

The electrolytic cell was operated using the above anode and under the same conditions as in the example.

The battery voltage was 3.30V.

[Brief explanation of the drawing]

1 and 2 are top views showing a conventional movable metal electrode, FIGS. 3, 4, and 6 are top views showing a movable electrode of the present invention, and FIG. 5 is a top view showing a movable metal electrode of the present invention. FIG. 3 is a perspective view showing a sex electrode. Moreover, FIG. 7 is a schematic diagram of an electrolytic cell used in an example of the present invention. In the figure, 1 is an electrode surface, 2 is a current collector rod, 3 is a conductive member, 4 is a thin part, 5 is a conductive part, and 6
is an electrode holder.

Claims (1)

[Scope of Claims] 1. An electrode in which a movable conductive member is used to connect an electrode surface and a current collector rod, and the distance between the current collector rod and the electrode surface can be changed. A movable metal electrode characterized by the presence of some thin parts. 2. The movable metal electrode according to claim 1, wherein 5 to 30% of the total area of the conductive member is partially thin. 3. The movable metal electrode according to claim 1, wherein the movable metal electrode is present over the entire length in the longitudinal direction of the partially thin portion. 4. The movable metal electrode according to claim 1, wherein the thickness of the thin portion is 1/3 or less of the thickness of the other portion.