JPS6059089A - Electrolytic device for generating continuously monosilane - Google Patents

Abstract

PURPOSE:To decrease bath resistance and to improve electric power efficiency by providing a salt convection port with a circular columnar anode as the center of a cylindrical cathode thereby obviating solidification owing to the biased comps. of the eutectic salt. CONSTITUTION:A graphite anode 13 is made into a circular columnar shape and a cylindrical cathode 14 is provided to face the anode as a center. The bottom end of the cathode 14 is lowered more than the bottom end of the anode 13 in order to prevent the leakage of an electric field from the side face and to prevent the leakage of the electric field from the lower part of the electrodes. A salt convection port 11 is provided to the wall of an anode chamber 16 below the eutectic salt interface 15 to accelerate the convection of the eutectic salt in the electrolytic part. The above-described purpose is then attained.

Description

[Detailed description of the invention] The present invention relates to an electrolytic device for continuous generation of monosilane.

Concerning an electrolysis device used to melt a mixed salt of potassium chloride and lithium chloride in an inert gas atmosphere in conventional electrolysis for continuous generation of monosilane, generate an electric charge, and extract chlorine gas and lithium. is a special public official in 1977
-3660 and Japanese Patent Application No. 55-72789.

A schematic diagram of the conventional electrolyzer is shown in FIG.

The electrolyzer is, for example, 100% medium, 30% thick, and 1
Four 200% carbon plate-shaped anodes 1 and nickel plate-shaped cathodes 2 face each other in a potassium chloride/lithium chloride eutectic salt 3 with an interpolar distance of 11i1U8o to 100%.

Further, in order to prevent leakage of chlorine 4 electrolytically generated from the anode 1 to other parts and to prevent recombination with lithium 12 generated at the cathode 2, a metal diaphragm 5 with an oval cross section is provided between the frames 1 and the cathode 2.
It is installed so that the distance ratio between the two poles is 2:1.

On the other hand, positive lid 1 +1'-J: It is set in the center of the anode chamber 6 of a long cylindrical shape whose lower end is always submerged in eutectic salt, and the chlorine gas 4 generated by electrolysis is sent to the tank from the upper gas output lower part of the anode chamber 6. taken outside.

The cathode 2 is, for example, +j+ 500%, 16+ 400%,
The upper part has a sharp plate shape, and above it there are several lithium 4 collection and transfer devices 8 for collecting lithium metal generated by electrolysis and separated from the cathode plate and guiding it to other parts. There is.

In addition, the lead parts of both the cathode and anode are insulated and soled with Teflon insulation parts 9 and attached to the upper reaction tank lid.
There are 91 buildings and 7.

When electrolysis is carried out using the electrolysis device of this conventional example, if the convection speed of the eutectic salt within the electrolysis device is equal to or higher than the electrolytic speed, then the eutectic salt composition There is no deviation, and normal electrolysis can continue.However, in the structure of the conventional electrolyzer, there is no convection opening 11 for eutectic salt near the anode chamber interface 10 as shown in Fig. 3, so convection is suppressed. Convection of the eutectic salt commensurate with the electrolysis rate could not be obtained. Therefore, as the electrolysis rate increases, the bath resistance increases, and in extreme cases, changes in the composition of the eutectic salt may lead to assimilation, making it impossible to continue electrolysis.

In addition, since there is no eutectic salt convection port, carbon powder disintegrated by electrolysis accumulates at the interface 10, creating a short circuit phenomenon, and as a result, for example, chlorine is generated in the metal material of the furnace wall, and the furnace wall Corrosion of metal materials and a decrease in electrolytic efficiency occurred.

Furthermore, as described above, since the plate-like facing electrode structure is used, the electric field leaks to areas other than between the opposing surfaces of the electrodes, which may lead to electrolytic corrosion of metal structural materials other than the electrodes.

The present invention provides a means to solve these problems.

The gist of the present invention is an electrolytic device for continuous generation of monosilane, which is characterized by having a cylindrical anode at the center, a cylindrical cathode facing the anode, and a eutectic salt convection port. Exists in electrolysis equipment.

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the present invention will be explained using drawings.

FIG. 3 shows an embodiment of the electrolyzer according to the present invention;
The figure is a diagram showing a BB cross section in FIG. 3.

In order to prevent leakage of the electric field to parts other than the electrodes, as shown in FIGS. 3 and 4, the present invention provides a graphite anode 13 with a cylindrical shape and a cylindrical shape that faces the anode. , a cylindrical cathode 14 was provided. That is, the cylindrical cathode surrounds the side surface of the cylindrical anode, and in order to prevent electric field leakage from the side surface and to prevent field leakage from the lower part of the electrode, the lower end of the cathode 14 is connected to the lower end of the anode 13. It has a structure that is lowered significantly and envelops the electric field.

First, since the chlorine gas 4 generated during electrolysis rises due to buoyancy, an upward force acts on the eutectic salt in the electrolysis section. As mentioned above, if the salt is shaped like a bag, the convection of the salt will be suppressed and various problems will occur.

For this reason, in the present invention, as a means to eliminate the bag state by providing an opening in the upper part, the opening is provided in the lower part of the eutectic salt interface 15, in the anode chamber 6.
A salt convection port 11 was provided in the wall of the chamber to promote convection of the eutectic salt in the electrolytic section.

As a result, in the electrolytic section, suction from below, salt convection port 1
The smooth convection of the eutectic salt flowing out of the bath is promoted, eliminating the assimilation phenomenon caused by the uneven composition of the eutectic salt that causes potassium chloride to enter a lynch state in the electric field, and at the same time reducing the bath resistance. was measured, and power efficiency was improved.

In addition, by promoting the convection of the salt, the lateral spread 9 of the chlorine gas 4 generated within the eutectic salt becomes smaller, resulting in a chlorine trapping network located between the poles within the eutectic salt. Cylindrical diaphragm 16
No more chlorine gas leaking from the to the cathode side.

This eliminated the M bond reaction between the leaked chlorine gas and the lithium generated at the cathode, making it possible to further reduce the distance between the electrodes.

Next, by providing the salt convection port 11, the convection occurs due to the collapse of the anode surface as a result of snow melting, and the anode chamber eutectic salt interface 15
By periodically pressurizing the anode chamber and releasing the graphite powder suspended in the anode chamber from the ground convection port 11, it was possible to eliminate the short-circuit phenomenon and continue a stable electrolytic reaction for a long time.

Example 1 The anode chamber 6 is made of a cylinder made of Lc-Nl with an inner diameter of 380% f1 and a thickness of 5%, and is open 400% below the eutectic salt interface 15.

Two ground convection ports 11 are opened in the anode chamber wall at 75% below the eutectic salt interface 15, and the size thereof is 60% in height and 310% in width.
A roof-like cover 17 is attached to the opening, and the salt exiting from the ground convection opening 11 is directed downward. By installing a cover, we prevent chlorine from leaking from this part to other parts due to electrolysis.

The anode 13 made of graphite is made of a solid rod of 300% f, and the Φ penetration depth is 1100% below the eutectic salt interface 15.

The surface area of the anode 13, which faces the cathode 14 and contributes to electrolysis, is about 6100 cbf. In addition, the electrolytic current during electrolysis is I'11.5000 A, and the current density is 0.8.
A/-1 pole-to-pole ship is 60X.

In order to prevent chlorine gas generated during electrolysis from leaking to other parts and to prevent recombination with lithium generated at the cathode 14,
1 () Menon metal cylindrical diaphragm 16 is 35% between anode 13 and diaphragm 16, diaphragm 16 and negative @i, 14 INj25
cents in % intervals.

The cathode 14 has an inner diameter of 420 mm, a length of f1, and a length of 742' The bottom end is anode 1 for electric field containment.
It is 100% down from the bottom of 3.

Electrolysis under the above conditions? Continuing to achieve chlorine generation efficiency of 98%14
It's 1. In addition, the eutectic salt interface 15 for preventing the short phenomenon
The operation of expelling suspended matter outside the anode room is carried out once every 24 days.
The implementation of 0 (+l1li1) carried out in the 1:sequence is as follows.

Furthermore, the anode chamber 6 is pressurized to expel the collapsed graphite powder floating at the interface 15 from the ground convection port 11 together with the replacement gas, and after repeating the process several times to return the anode chamber to a predetermined pressure, the electrolysis begins. Gradually increase the current and continue electrolysis at 5 [u+A.

As detailed above, < , lJ4 pole] 3 is cylindrical,
Since the ground convection port 11 is provided below the eutectic salt interface 15 of the anode chamber 6, the effect of increasing the generated chlorine is increased, and the composition of the salt in the electrolytic part is prevented from being biased such as potassium chloride lynch. By lowering the bath resistance of the electrolytic part and moving the eutectic salt whose temperature has increased, it has become possible to suppress the temperature rise of the eutectic salt, making it possible to maintain stable electrolysis over a long period of time. Ta.

In addition, by providing a salt port 11 under the soot interface on the side of the anode chamber, it is possible to periodically discharge graphite powder, which is a substance that causes short circuits and disintegrates due to electrolysis and floats in the anode tail, to the outside of the anode tail. As a result, it has greatly contributed to improving the efficiency of the Electric Power Agency f.

Furthermore, the lower end of the cathode 14 is 100X lower than the lower end of the anode 13.
By lowering it, the electric field was contained and the risk of electrolytic corrosion was eliminated.

[Brief explanation of drawings]

FIG. 1 shows a conventional electrolysis device, and FIG. 2 shows a cross section taken along line AA in FIG. FIG. 3 shows an embodiment of the electrolyzer according to the present invention;
The figure is a cross-sectional view taken along line BB in FIG. 3. 3... Eutectic salt, 6... Anode chamber. 9...Insulating parts, 11...Ground convection opening. 12...Lithium, 13...Cylindrical anode. 14... Cylindrical shade, 15... Eutectic salt interface. 16...-Cylindrical diaphragm, 17...Cover. Patent applicant: Director of the Agency of Industrial Science and Technology Figure 1

Claims (1)

[Scope of Claims] 1. An electrolytic device for continuous monosilane generation, characterized by having a cylindrical anode 13 at the center, a cylindrical cathode 14 facing the anode, and a salt convection opening 11. electrolysis equipment. 2. The electrolytic device according to claim 1, wherein the lower end of the cathode 14 is lower than the lower end of the anode 13 so as to transmit an electric field. 3. The electrolyzer according to claim 1, wherein the salt convection port 11 is provided in the anode chamber wall below the eutectic salt interface 15. 4. The electrolysis device according to claim 1, characterized in that a cylindrical diaphragm 16 is provided between the anode 13 and the cathode 14.