JPH0457Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an electrolytic cell using an ion exchange membrane, particularly an electrolytic cell having a structure in which an elastic packing is provided on both sides or one side of the membrane to tighten the electrolytic cell chamber frame. The purpose is to achieve a complete seal by fixing and to prevent damage to the membrane due to tightening.

For example, an electrolytic cell for alkaline chloride aqueous electrolysis using an ion exchange membrane is divided by a membrane into an anode chamber and a cathode chamber (two-chamber electrolytic cell), or an anode chamber, an intermediate chamber, and a cathode chamber (three-chamber electrolytic cell). is forming. The membrane partitions between these chambers are usually constructed by arranging an ion exchange membrane between adjacent chamber frames and tightening the membrane with elastic packing mainly made of rubber.

However, when an elastic packing is used, the packing stretches together with the membrane during tightening, which sometimes causes membrane damage. In order to avoid this, it is necessary to make the manufacturing precision of the electrolytic cell and the thickness precision and physical properties of the elastic packing used uniform, but when actually manufacturing something on an industrial scale, certain Only precision products can be manufactured.
If the membrane is tightened using an elastic packing under such conditions, the membrane and the packing will both stretch during tightening, making it impossible to eliminate the occurrence of damage.

The inventors of the present invention conducted various tests to solve this problem, and found that a rubber material with coagulability that acts as a lubricant when attached to the battery case and solidifies afterwards was used between the ion exchange membrane and the elastic packing. By interposing a curable adhesive that exhibits lubricity in an organic solvent solution or in an uncured state, even if the elastic packing stretches during tightening, the membrane exhibits lubricity in an organic solvent solution of this rubber or in an uncured state. The curing adhesive provides slippage and does not stretch together, which prevents damage.Furthermore, when the battery case is used, the curing adhesive exhibits lubricity when used in an organic solvent solution of rubber or in an uncured state. It has been found that the mold adhesive can be prevented from leaking into the electrolyte and contaminating it.

Various types of rubber solutions in organic solvents or hardening adhesives that exhibit lubricity in the uncured state can be used, but it is preferable to use adhesives that are corrosion resistant to the solutions and products used. and does not elute harmful substances during electrolysis.
At least when the film is attached to the battery case, it acts as a lubricant, and then solidifies. Examples of curable adhesives that exhibit lubricity in an uncured state include thermosetting adhesives such as epoxy adhesives and polyurethane adhesives. The amount of the organic solvent solution of these rubbers or the curable adhesive that exhibits lubricity in an uncured state is sufficient to the extent that the lubrication effect is not impaired.

This will be explained below with reference to the drawings.

Fig. 1 shows the case where the electrolytic cell chamber frame and the exchange membrane are tightened using elastic packings on both sides of the membrane.There are elastic packings 3 on both sides of the membrane 1, and the electrolytic cell chamber frame It is tightened by.

Tightening can be done using hydraulic or pneumatic pressure, using bolts all the way through, or tightening each part individually using bolts. Between the elastic packing 3 and the membrane 1, a solution of rubber in an organic solvent or a curable adhesive exhibiting lubricating properties in an uncured state is applied. When the electrolyzer chamber frame 2 is tightened, the elastic packing 3 stretches inward and outward from a certain point, but the membrane sandwiched between the elastic packings does not stretch at all, only the elastic packing changes; The membrane will not be damaged.

Figure 2 shows the case where the elastic packing is on one side.
An organic solvent solution of rubber or a curable adhesive that exhibits lubricity in an uncured state is applied between the elastic packing and the membrane. One side of the membrane is coated with a suitable sealant. Even in this case, since only the elastic packing stretches during tightening, the membrane will not be damaged.

The membrane used here can be one with woven reinforcement or one in which fluorine-containing short fibers are uniformly inserted.

This will be explained below in Examples.

Example 1 Natural rubber gasket (thickness 6mm x length 40mm x width 40mm)
A Naphyllon membrane N-315 (manufactured by Dupont) was sandwiched between two sheets (mm) and pressed with a press at a surface pressure of 80 kg/cm ² to examine the state of damage to the membrane.

Tests in which butyl rubber dissolved in methyl ethyl ketone was inserted between the packing and the membrane showed no abnormalities, while those in which it was not inserted showed expansion of the mesh (reinforcing fiber weave) and damage to the membrane.

[Brief explanation of the drawing]

Each of the drawings is a partial longitudinal cross-sectional view showing the state in which the ion exchange membrane is arranged and tightened on the chamber frame of the electrolytic cell according to the present invention. The figure shows the case where an elastic packing is present on one side of the membrane. 1... Ion exchange membrane, 2... Electrolyzer chamber frame, 3...
...Elastic packing, 4... Curing adhesive that exhibits lubricity in an organic solvent solution of rubber or in an uncured state.

Claims (1)

[Scope of utility model registration request] In an electrolytic cell in which an ion exchange membrane is tightened and fixed within the electrolytic cell chamber frame with elastic packing on both or one side, an organic solvent solution of rubber or an uncured rubber is applied between the ion exchange membrane and the elastic packing. An ion exchange membrane electrolytic cell that is tightened with a hardening adhesive that exhibits lubricity.