JPH06136586A - Cathode plate for electrolysis - Google Patents

Abstract

PURPOSE:To produce the cathode having good quality by forming the cathode plate for electrolysis of a hanger bar and metallic plate which are the same in rolling direction and a hanger. CONSTITUTION:This cathode plate for electrolysis is formed of the hanger bar 1 and the metallic plate (stainless steel plate) 2 and the hanger. The longitudinal direction of the hanger bar 1 and the rolling direction of the metallic plate 2 are, thereupon, set the same. As a result, the variations in the thicknesses of a master mold and within the plates are decreased, by which the good plate is molded in a molding stage.

Description

Detailed Description of the Invention

[0001]

[Industrial field] Cathode plates for electrolysis, such as stainless steel, titanium, and copper, used for producing a seed plate used as a cathode for electrolytic refining and electrowinning of copper, nickel, etc., or a seed plate The present invention relates to an electrolysis cathode plate for directly electrodepositing a high-purity metal by omitting steps.

[0002]

2. Description of the Related Art Conventionally, a cathode plate for electrolysis used for electrolytic refining of metal has been used by appropriately cutting rolled stainless steel plate, titanium plate, copper plate or the like and hanging it on a hanger bar. At this time, the planarity and verticality of the electrolysis cathode plate become a problem, but the acceptance standard of the electrolysis cathode plate is, for example, a stainless steel plate having a flatness conforming to the JIS standard (cold rolled stainless steel plate, JIS G4305). It is judged whether or not there is. That is, the flatness when the stainless steel plate is laid on a surface plate is specified to be 3 mm or less, and a stainless steel plate conforming to this specification is used.

However, in actuality, when a stainless steel plate or the like conforming to such regulations is hung on a hanger bar for use, the plate strain when hung down is lower than the flatness when laid on a surface plate. , Shows a tendency to increase. For this reason, short circuits frequently occur in the electrolysis process, which causes a decrease in current efficiency. In addition, since a variation in the thickness of one seed plate occurs, a seed plate with large strain can be formed in the seed plate molding process by rolls or presses. There is a problem that it leads to deterioration of the quality of the cathode.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide an electrolysis mother plate having good flatness and verticality.

[0005]

The cathode plate for electrolysis of the present invention is characterized in that it comprises a hanger bar, a metal plate whose rolling direction is the same as the longitudinal direction of the hanger bar, and a hanging hand. .

[0006]

The applicant has investigated the characteristics of the stainless steel plate, titanium plate, and copper plate used as the base plate for the production of the electrolysis seed plate, and as a result, found that the flatness of the base plate varies due to various causes. found. That is, since the radius in the roll direction varies depending on the position when the plate is cut out from the rolling coil (outer circumference, inner circumference), the flatness of the plate is likely to vary. Further, the flatness of the plate is likely to vary depending on the manufacturing lot. Further, it is conceivable that various strains may occur in the process of converting the stainless steel plate into the mother plate, which causes variations in flatness of the plate. That is, as shown in FIG. 2, the stainless steel mother plate has a structure in which a stainless steel steel plate 2 is welded with a copper sling and is joined to the hanger bar 1 with bolts and nuts 4, and then the hanger bar and sling are welded. However, the occurrence of distortion in the manufacturing process is as described below. Arrival of stainless steel plates → Process of cutting to a certain size (cutting distortion occurs) →
Welding two copper slings to a stainless steel plate (welding distortion occurs) → Assembling the hanger bar and sling with bolts (assembly error occurs) → Welding hanger bar and sling (welding distortion) Occurrence).

Among the variations in flatness caused by various strains as described above, pay attention to the strain (also called curl) generated when a stainless steel plate is rolled and then wound into a coil, and reduce this effect. The present invention has been made in consideration of the above.

That is, when the longitudinal direction of the hanger bar 1 and the roll direction of the stainless steel plate are at right angles, FIG.
In contrast to the above-mentioned strains, which appear remarkably as shown in (b) and (b), when the longitudinal direction of the hanger bar 1 and the roll direction of the stainless steel plate are made to be the same as in the electrolytic cathode plate of the present invention, FIG.
As described in (a) and (b), the above strain is considerably suppressed.

The effect of suppressing strain according to the present invention is shown in FIG. FIG. 4 shows that the plate strain in the bb 'section of the stainless steel plate is measured by a laser strain measuring device (a structure in which laser light is irradiated from the side to measure the distance between each point of the plate and the center line). 4 (a) is a plate distortion when the stainless steel plate is simply suspended without being attached to the hanger bar, and FIG. 4 (b) is a plate when the stainless steel plate is attached to the hanger bar. It is in a distorted state.

In the case of a mother plate assembled so that the longitudinal direction of the hanger bar and the roll direction of the plate made of stainless steel or the like are suspended at right angles, the lower part of the mother plate may be displaced from the center of the hanger bar by about 20 mm. Therefore, in the case of normal copper electrolysis, the distance between the surface of the anode and the surface of the stainless steel base plate is about 30 mm, which causes a short circuit or the like, and is therefore not preferable as the base plate.

Further, the plate strain when the stainless steel plate or the like is simply hung is 3 mm or more, and the mother is assembled so that the longitudinal direction of the hanger bar and the roll direction of the plate such as stainless steel are hung in the same direction. Even in the case of a plate, the maximum strain of the mother plate becomes 8 mm or more, and the distance between the anode and the stainless steel mother plate varies, so that the variation in the thickness of one seed plate becomes large, which is not desirable as a mother plate. .

In the case of a mother plate assembled such that the suspended plate strain of a stainless steel plate or the like is less than 3 mm and the longitudinal direction of the hanger bar and the roll direction of the plate such as stainless steel are suspended in the same direction, stainless steel is used. Since the plate strain of the steel plate is corrected by the hanger bar, the maximum strain of the mother plate becomes less than 7 mm, and it is possible to manufacture a good seed plate with less variation in the thickness of one seed plate. Therefore, according to the method of the present invention, it is possible to assemble a mother board having good flatness and verticality.

[0013]

[Examples] The following electrolytic conditions were tested, and the results obtained are shown in Table 1. Electrolysis conditions Electrolyte copper 46 g / l Free sulfuric acid 190 g / l glue 80 g / ton (per amount of electrodeposited copper) Thiourea 60 g / ton (per amount of electrodeposited copper) Hydrochloric acid 30 mg / l Anode cast copper anode Anode size 1040 mm × 1026 × 36mm Number of anodes 26 sheets Anode stainless steel 316L / Cold rolled plate Nippon Stainless Steel Co., Ltd. Anode size 1070mm × 1050mm × 3mm Number of anodes 25 sheets Distance between electrodes 105mm (distance between anode centers) Current density 220A / m ² Liquid temperature 60 ° C Electrolysis time 22 hours Battery case size 3000mm × 1250mm × 1360mm

Anode 1 life (energization 18 times) was carried out under the above-mentioned conditions, and several plate thicknesses were measured at 100 points on a seed plate having a unit weight of 6.5 kg (the measurement points were cut with a shear, Digital micrometer, manufactured by Mittyo,
The minimum unit is 1 μm). Here, the seed plate was formed by a roll method, and the state of the seed plate after forming, that is, the degree of strain of the seed plate was visually observed. Further, the plate strain of the stainless steel plate and the plate strain of the mother plate were measured by the above-mentioned method. Regarding the mother plate, the center of the hanger bar was used as a reference line, and the difference between the maximum value and the minimum value was defined as the mother plate maximum strain in Table 1. Indicated.

[0015]

[Table 1]

In Table 1, the mother board assembling method A is a method of assembling so that the longitudinal direction of the hanger bar and the roll direction of the stainless steel plate are the same, and B is the method of assembling the hanger bar and the roll of the stainless steel plate. This is a method of assembling so that the directions are at right angles.

[0017]

As described above, according to the present invention,
A mother board with good verticality and flatness can be assembled. Further, by using the mother plate of the present invention, variations in the thickness of the seed plate and the thickness of the inside of the plate are reduced, so that a good seed plate can be formed in the forming step. Furthermore, by using a seed plate having good verticality and flatness, it is possible to produce a cathode of good quality.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, in which (a) is a front view and (b) is a side view.

FIG. 2 is a diagram showing an assembly structure of an electrolysis mother plate.

FIG. 3 is a view showing a comparative example, (a) is a front view,
(B) shows a side view.

FIG. 4 is a diagram in which the plate strain in the bb ′ cross section of the electrolysis mother plate (FIG. 2) is measured, and FIG. 4 (a) is a diagram when it is simply hung before being assembled to the mother plate. , (B) are diagrams when assembled on a mother board.

[Explanation of symbols]

 1 Hanger bar 2 Stainless steel plate 3 Ear plate 4 Bolts and nuts 5 Edge material

Claims (1)

[Claims] 1. A cathode plate for electrolysis, comprising a hanger bar, a metal plate whose rolling direction is the same as the longitudinal direction of the hanger bar, and a hanging hand.