JPH0971891A - Method for electrorefining metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformize the amt. of a metal deposited on a cathode face and to improve the type of packing by shifting the center position of a cathode in each electrolytic cell from the center position of the opposed anode toward a positive common conductive part on the electrical contact side of the anode. SOLUTION: The principal part of an electrolytic cell 1 is formed with a square electrolytic cell main body 10, a strip common conductive part 11 provided on the upper faces of both side walls and an insulating coating film 12 laminated on the conductive part 11 and provided with plural almost U-shaped notches 2. One sides of the anodes 3 are restrained on one common conductive part 11 on one side through the notches 2, the other sides of the cathode 4 are restrained on the insulating coating film 12 on the other side, the one sides of the cathodes 4 are restrained on a common conductor 2 through the notches 2, and the other sides are restrained on the insulating coating film 12. At this time, the center position of the cathode in the cell 1 is shifted from the center position of the anode 3 by 5-10mm toward the common conductive part on the electrical contact side of the anode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for electrolytically refining metals such as copper, and more particularly, to an improvement in a method for electrolytically refining metals which can make the amount of metal deposited on a cathode surface uniform and improve its packing. is there.

[0002]

2. Description of the Related Art Metal electrolytic refining of copper or the like is performed by, for example, as shown in FIG. 3, a thin copper plate (cathode body) a1 called a seed plate and a pair of conductive slings obtained by cutting the thin copper plate into strips. A plurality of cathodes a composed of a member a2 and a conductive rod member a3 made of a metal rod or the like and called a cross beam,
It is performed using a plurality of anodes b manufactured by casting blister copper. Then, a large number of electrolytic cells c in which a plurality of the cathodes a and the anodes b opposed to the cathodes a are alternately inserted at narrow intervals of about 30 mm are used.
It is general that these cathodes a and anodes b are connected in parallel in the electrolytic bath c, and serially connected between the electrolytic baths c. This is due to problems with rectifier capacity and equipment.

More specifically, as shown in FIG. 3, in the electrolytic cell c, the cathode a and the anode b are suspended by suspending them on the upper surfaces of both side walls of the electrolytic cell c with their upper ends on both sides as fulcrums. One side wall upper surface has a positive contact, the other side wall upper surface has a negative contact, and a position facing each contact is an insulator. That is, as shown in FIG.
As shown in FIGS. 4 (A) and 4 (B), a common conductive portion d made of a strip-shaped metal plate and the like, and an insulating property provided with a substantially U-shaped cutout portion e1 laminated on the common conductive portion d. A coating e is provided, and the upper end on one side of each anode b is locked onto the common conductive portion d provided on the upper surface of one side wall through the cutout portion e1 of the insulating coating e, and the other upper end. Are locked and arranged on the insulating coating e provided on the upper surface of the other side wall. Also, for each cathode a, one end of the rod-shaped member a3 is locked onto the common conductive portion d provided on the upper surface of the other side wall through the cutout portion e1 of the insulating coating e, and the rod-shaped member
Insulating film e provided on the upper surface of one side wall of the other end of a3
It is arranged to be locked on the top. Then, as shown in FIGS. 4 (A) and 5, each cathode a of the electrolytic cell c is connected to the anode b of another adjacent electrolytic cell c via the common conductive part d, and the electrolytic cell c is also similarly connected. Each anode b is connected to a cathode a of another adjacent electrolytic cell c via a common conductive portion d. In FIG. 5, the region shown by the broken line is the electrolytic cell c, and the solid line schematically shows the wiring state between the power source f and the cathode a and the anode b in each electrolytic cell c.

[0004]

By the way, when the above-mentioned connection method is adopted for the cathode and the anode, the current density distribution per unit area in the cathode becomes non-uniform, and the obtained electric metal such as copper is obtained. In some cases, only one end of the plate grew and became thick, and the other end became thin and thin.

When such electric metal plates are stacked, not only the packing shape is not rectangular but the appearance is deteriorated, but also the unbalanced packing shape is liable to collapse and has a problem in transportation. Was.

Therefore, conventionally, a method has been adopted in which the electric metal plates are inverted one by one so that the thickened ends do not pile up on one side, and are stacked so that the packing shape is close to a rectangle. However, this method has another problem that it requires complicated equipment and it takes too much time for packing.

The present invention has been made by paying attention to such a problem, and a problem thereof is a metal electrolytic refining method capable of making the amount of metal deposited on the cathode surface uniform and improving the packing appearance. To provide.

[0008]

The inventors of the present invention have made extensive studies as to the cause of non-uniformity of the current density distribution in the cathode when the above-mentioned connection method is adopted for the cathode and the anode. The present invention has been completed by finding out that the material is used for the cathode and the anode.

That is, the seed plate used for the cathode is manufactured by processing a metal plate having a purity of about 99.99% obtained by electrolytic refining or the like. Therefore, its specific resistance is low. On the other hand, the metal used as the anode is, for example, about 99.2% crude copper in electrolytic refining of copper, and its specific resistance is higher than that of the cathode.

When the electric resistances of the cathode and the anode are different from each other as described above, it is natural that the lower the resistance, the easier the current flows. For this reason, when the above-mentioned connection method is used for connecting the cathode and the anode, between the cathode and the anode in the electrolytic cell, the cathode close to the contact point for connecting the anode and the cathode of the adjacent electrolytic cell is connected. The current is likely to be concentrated in the portion, the current density in this portion increases, and the current density distribution becomes non-uniform. The present invention has been completed based on such technical findings.

That is, in the invention according to claim 1, a plurality of electrolytic cells each having a common conductive portion are arranged adjacent to each other on the upper surfaces of both side walls, and a cathode and an anode opposed thereto are provided in each electrolytic cell. A plurality of them are alternately arranged by locking both upper ends thereof to the upper surface of the side wall, and one of the common conductive portions is positively connected to each anode, while the other common conductive portion is negatively connected to each cathode, In addition, each cathode of the electrolytic cell is connected to the anode of another adjacent electrolytic cell through the common conductive portion, and each anode of the electrolytic cell is connected to the cathode of another adjacent electrolytic cell through the common conductive portion. Assuming a metal electrorefining method in which electric current is supplied to the anode and cathode in each electrolytic cell to perform electrolytic refining of metal, the anode in which the center position of the cathode in each electrolytic cell opposes It is characterized in that the offset arrangement in the positive common conductive side is the anode of the electrical contact side with respect to the center position.

When the center position of the cathode in the electrolytic cell is displaced from the center position of the opposing anode to the positive common conductive portion side, which is the electric contact side of the anode, the current concentration due to the above-mentioned wiring system is concentrated. Since the area of the cathode that receives the current in the region is widened, the current density distribution per unit area in the cathode can be made uniform. As a result, the amount of metal deposited on the cathode surface becomes uniform and the film thickness becomes substantially uniform, so that the packing appearance when these electric metal plates are stacked can be improved.

Regarding how much the cathode is displaced to the positive common conductive part side which is the electric contact side of the anode, the material, structure, size and shape of the anode and the cathode to be applied, and the electrolytic solution to be applied Although it cannot be uniformly determined depending on the composition, the voltage applied between the anode and the cathode, and the like, it is about 5 mm to 10 mm in the case of the materials and scales disclosed in the following embodiments of the invention. The invention according to claim 2 relates to the invention in which the shift amount of the cathode is specified.

That is, the invention according to claim 2 is premised on the metal electrolytic refining method according to the invention according to claim 1, in which the central position of the cathode is from the central position of the anode to the electric contact side of the anode, and the positive common conductivity. It is characterized in that they are arranged so as to be displaced from each other by 5 mm to 10 mm.

Further, the method of displacing the center position of the cathode from the center position of the anode to the positive common conductive part side which is the electric contact side of the anode is arbitrary, and the method of displacing the whole cathode as it is to the positive common conductive part side is as follows. It is illustrated. When the cathode is composed of the conductive rod-shaped member described in the prior art, a plate-shaped cathode main body, and a pair of conductive hanging members that connect the cathode main body to the rod-shaped member, It is possible to make the current density distribution in the cathode uniform without shifting the position of (1) to the positive common conductive portion side. That is, the mounting position of the conductive handle member that connects the conductive rod-shaped member and the cathode body, which is the seed plate, is set so as to be shifted to the side opposite to the positive common conductive portion side, which is the electrical contact side of the anode. This makes it possible to make the current density distribution in the cathode uniform. Instead of the usual method in which a hanging member having the same width is provided so as to be equidistant from both ends of the seed plate, the mounting position of the hanging member is the positive common conductive portion side which is the electric contact side of the anode. This is because it can be improved so that the current flows evenly on the cathode surface by shifting the setting to the opposite side. Further, by setting the area and / or thickness of the hanging member located on the side opposite to the positive common conductive portion side, which is the electric contact side of the anode, larger than that of the other hanging member, the electric contact of the anode is formed. A sufficient current can be made to flow to the cathode portion on the side opposite to the side.
The inventions according to claims 3 and 4 are made for such technical reasons.

That is, in the invention according to claim 3, a plurality of electrolytic cells each having a common conductive portion are arranged adjacent to each other on the upper surfaces of both side walls, and a cathode and an anode opposed thereto are provided in each electrolytic cell. A plurality of them are alternately arranged by locking both upper ends thereof to the upper surface of the side wall, and one of the common conductive portions is positively connected to each anode, while the other common conductive portion is negatively connected to each cathode, In addition, each cathode of the electrolytic cell is connected to the anode of another adjacent electrolytic cell through the common conductive portion, and each anode of the electrolytic cell is connected to the cathode of another adjacent electrolytic cell through the common conductive portion. Assuming a metal electrolytic refining method in which electric current is supplied to the anode and cathode in each electrolytic cell to perform electrolytic refining of metal, the cathode in each electrolytic cell has both ends locked to the upper surface of the side wall. A conductive rod-shaped member, a plate-shaped cathode body, and a pair of conductive hanger members for connecting the cathode body to the rod-shaped member, and the mounting position of the hanger member to the cathode body, The invention is characterized in that the anode is set to be shifted to the side opposite to the positive common conductive portion side which is the electric contact side of the anode, and the invention according to claim 4 is an electrolytic cell having a common conductive portion on the upper surfaces of both side walls, respectively. Are arranged adjacent to each other, and a plurality of cathodes and anodes opposed to the cathodes are alternately arranged in the respective electrolytic cells with the upper ends of both sides being locked to the upper surface of the side wall, respectively. One is connected to each anode as positive and the other common conductive part is connected to each cathode as negative, and each cathode of the electrolytic cell is connected to the anode of another adjacent electrolytic cell through the common conductive part. Metal electrorefining in which each anode of the electrolysis cell is connected to the cathode of another adjacent electrolysis cell through the common conductive part and electric current is supplied to the anode and cathode in each electrolysis cell to perform electrorefining of metal. Based on the method, the cathode in each electrolytic cell is provided with a conductive rod-shaped member whose both ends are locked to the upper surface of the side wall, a plate-shaped cathode main body, and a pair of the cathode main body connected to the rod-shaped member. The area and / or the thickness of the suspender member which is composed of the conductive suspender member and is located on the side opposite to the positive common conductive portion side which is the electric contact side of the anode is larger than that of the other suspender member. The feature is that it is set large.

The metal material to which these technical means are applied is arbitrary, and metal refining of copper, nickel, cobalt or the like is exemplified. The invention according to claim 5 relates to the invention in which the invention according to claims 1 to 4 is applied to a copper metal electrolytic refining method.

That is, the invention according to claim 5 is premised on the electrolytic metal refining method according to any one of claims 1 to 4, and is applied to electrolytic refining of copper. is there.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

First, the electrolytic cell 1 applied in the practice of the invention is the same as the electrolytic cell conventionally used as shown in FIG. That is, the electrolytic cell 1 is a rectangular electrolytic cell body 10, strip-shaped common conductive portions 11 and 11 provided on the upper surfaces of both side walls, and stacked on the common conductive portions 11 and 11 and having a substantially U-shape. The insulating coatings 12, 12 having a plurality of cutouts 2 form a main part thereof.

1050 m in width obtained by casting blister copper
m, length 1030mm, thickness 38mm and its weight is 360
Twenty-six (26) kg of purified anodes 3 were placed in the electrolytic cell 1 so that the distance between each anode was 105 mm. Also,
As shown in FIG. 2, a seed plate (cathode body) 41 having a width of 1070 mm, a length of 1050 mm, and a thickness of 0.7 mm, and a pair of hanging members 42 made of ribbons obtained by cutting the same seed plate into strips. The cathode 4 is constituted by the cross beam 43 passed through the hanging member 42, and 27 cathodes 4 are placed in the electrolytic cell so that the anode is arranged between the cathode and the cathode. . Incidentally, the mounting portions of the pair of hanging members 42, 42 are set so as to be equidistant from both ends of the seed plate (cathode body) 41 as shown in FIG.

Further, with respect to the 27 cathodes 4, a part thereof is located 5 mm, 10 mm, 15 m from the center position of the anode 3 where the center position of the seed plate (cathode body) 41 is opposed
The seed plate (cathode body) 41 is moved so as to be displaced by m toward the electric contact side of the anode 3 (opposite to the electric contact side of the cathode 4) (moved in the direction indicated by the arrow in FIG. 1).
The hanging position of was changed to the position shown by the broken line.

The electrolytic solution has a liquid temperature of 60 ° C. and Cu of 4
5 g / l, sulfuric acid has a composition of 190 g / l, and 80 g / Cu-t of glue (the amount added per ton of electrolytic copper) and 60 g / Cu-t of thiourea are added as additives. Then, the average current density is set to 300 A / m ² and 2
Energized for 00 hours.

After energizing for 200 hours, the generated electrolytic copper was pulled up, washed, and the central portion of the cathode was cut in the lateral direction, and the thickness of the cut portion divided into two equal parts was measured with a micrometer from the end to 5 mm. Measured at intervals. In this example, the anode contact is on the north side and the cathode contact is on the south side.

As a result of measuring the variation in the thickness of the cross section, it was confirmed that the electrodeposited thickness changed within 60 mm to 80 mm from both ends in each case. 14mm ~ 15mm in this case in any case
In contrast, the thickness of the electrolytic copper obtained by setting the cathode in the normal position is about 1 mm thicker at the north end, but about 5 mm thinner at the south end, and 6 mm thick at the north and south ends. Was there. Then, when 18 sheets of electrolytic copper obtained by setting the cathode in a normal position were stacked in the same direction, the deviation in thickness was about 100 mm and the packing appearance was extremely poor.

On the other hand, the cathode 4 is 5 mm to 15 m northward.
When the distance is shifted by m, the north end becomes thinner as the amount of shift is increased, and when the distance is shifted by 5 mm, it is 14 m.
The thickness is about m, and it is 11m when displaced by 10mm.
When the thickness is about 15 m, or when it is displaced by 15 mm, it is 9.
The thickness was about 5 mm. However, the thickness at the southern end was almost 14.5 mm. Therefore, even if 18 electrolytic coppers obtained under these conditions were stacked in the same direction, the deviation in thickness was about 20 mm, and there was no problem at all.

[0027]

According to the metal electrorefining method of the present invention, the current density distribution per unit area in the cathode can be made uniform, so that the amount of metal deposited on the cathode surface can be made uniform. Therefore, the film thickness can be controlled substantially evenly.

Therefore, the rectangular shape of the packing obtained by stacking a plurality of the obtained electric metal plates is improved, and the bias of the current to the cathode end portion is reduced, so that the short circuit during energization can be reduced. It has the effect that can be done.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of an electrolytic cell according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view of a cathode according to an embodiment of the present invention.

FIG. 3 is a schematic perspective view of an electrolytic cell according to a conventional example.

FIG. 4 (A) is a plan view of an electrolytic cell, and FIG. 4 (B) is a sectional view taken along the line BB of FIG. 4 (A).

FIG. 5 is an explanatory view schematically showing a wiring state between a power source and a cathode and an anode in each electrolytic cell.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrolyte tank 2 Notch part 3 Anode 4 Cathode 10 Electrolyzer body 11 Common conductive part 12 Insulating film

Claims (5)

[Claims] 1. A plurality of electrolyzers each having a common conductive part are arranged adjacent to each other on the upper surfaces of both side walls, and a cathode and an anode opposed to the electrolyzer are disposed in the respective electrolyzers on both sides of the upper end on the upper surface of the side wall. A plurality of them are locked and arranged alternately, and one of the common conductive portions is positively connected to each anode, while the other common conductive portion is negatively connected to each cathode, and each cathode of the electrolytic cell is connected to each cathode. The anode of another electrolytic cell is connected to the anode of another adjacent electrolytic cell through the common conductive portion, and each anode of the electrolytic cell is connected to the cathode of another adjacent electrolytic cell through the common conductive portion. In a metal electrolytic refining method in which electric current is supplied to the cathode to perform electrolytic refining of metal, the center position of the cathode in each electrolytic cell is electrically connected to the center position of the opposing anode. A metal electrolytic refining method, wherein the metal electrolytic refining method is arranged so as to be shifted to the positive common conductive portion side which is the point side. 2. The center position of the cathode is 5 from the center position of the anode to the positive common conductive portion side which is the electric contact side of the anode.
2. The metal electrolytic refining method according to claim 1, wherein the metal electrolytic refining is performed with a shift of 10 mm to 10 mm. 3. A plurality of electrolyzers each having a common conductive part are arranged adjacent to each other on the upper surfaces of both side walls, and a cathode and an anode opposed to the electrolyzer are disposed in the respective electrolyzers on both sides of the upper end on the upper surface of the side wall. A plurality of them are locked and arranged alternately, and one of the common conductive portions is positively connected to each anode, while the other common conductive portion is negatively connected to each cathode, and each cathode of the electrolytic cell is connected to each cathode. The anode of another electrolytic cell is connected to the anode of another adjacent electrolytic cell through the common conductive portion, and each anode of the electrolytic cell is connected to the cathode of another adjacent electrolytic cell through the common conductive portion. In a metal electrolytic refining method of supplying an electric current to a cathode to perform electrolytic refining of a metal, a cathode in each electrolytic cell is provided with a conductive rod-shaped member whose both end sides are locked to the upper surface of the side wall and a plate-shaped cathode. A cathode main body and a pair of conductive hanging members for connecting the cathode main body to the rod-shaped member, and the mounting position of the hanging hand member with respect to the cathode main body is a positive common that is on the electric contact side of the anode. A metal electrolytic refining method, wherein the metal electrolytic refining method is set so as to be shifted to the side opposite to the conductive portion side. 4. A plurality of electrolytic cells each having a common conductive portion are arranged adjacent to each other on the upper surfaces of both side walls, and a cathode and an anode opposed to the electrolytic cell are arranged in each electrolytic cell on both sides of the upper end on the upper surface of the side wall. A plurality of them are locked and arranged alternately, and one of the common conductive portions is positively connected to each anode, while the other common conductive portion is negatively connected to each cathode, and each cathode of the electrolytic cell is connected to each cathode. The anode of another electrolytic cell is connected to the anode of another adjacent electrolytic cell through the common conductive portion, and each anode of the electrolytic cell is connected to the cathode of another adjacent electrolytic cell through the common conductive portion. In a metal electrolytic refining method of supplying an electric current to a cathode to perform electrolytic refining of a metal, a cathode in each electrolytic cell is provided with a conductive rod-shaped member whose both end sides are locked to the upper surface of the side wall and a plate-shaped cathode. And a pair of conductive sling members for connecting the cathode body to the rod-shaped member, and the sling is located on the side opposite to the positive common conductive portion side which is the electric contact side of the anode. A metal electrolytic refining method characterized in that the area and / or the thickness of the member is set larger than that of the other lifting member. 5. The electrolytic metal refining method according to claim 1, which is applied to electrolytic refining of copper.