JP2002285371A - Method for metal purification - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrolytic refining-electrolytic winning method by which a high purity metal can efficiently be produced by effectively utilizing an electrode and a electrolytic solution for electrolytic refining produced in an electrolytic refining stage. SOLUTION: This method for metal purification consists of: a stage where a coarse metallic raw material is electrolyzed by primary electrolysis to obtain a primarily electrodeposited metal; a stage where the primarily electrodeposited metal obtained by the primary electrolysis stage is subjected to electrochemical dissolution or acid dissolution with the primarily electrodeposited metal as an anode to obtain an electrolytic solution having high purity; and a stage where a high purity metal is obtained from the electrolytic solution having high purity by electrolytic winning.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a primary electrolysis that effectively utilizes an electrode and an electrolytic solution produced in an electrolysis process and, if necessary, a few electrolysis, and a method of purifying a metal by electrowinning (electrolytic refining). About how to convert. Further, the present invention relates to a high-purification method useful for high-purification of a metal in which the oxygen content caused by an organic substance is reduced. Further, the present invention provides a method for purifying Na in a metal which is highly purified in the above method,
The total content of alkali metal elements such as K is 1 ppm or less, and the total content of radioactive elements such as U and Th is 1 pp.
b or less, Fe, N
The present invention relates to a method for purifying a metal whose transition metal or heavy metal element such as i, Cr, Cu or the like is 10 ppm or less in total, and whose balance is highly pure and other inevitable impurities. The percentages, ppm and ppb used in the specification are all wt.
%, Wtppm and wtppb.

[0002]

2. Description of the Related Art Conventionally, 4N or 5N (99.9 each)
9 wt% and 99.999 wt%. ) When producing high-purity metals at the level, most are produced using electrolytic refining, but when electrolyzing the target metal,
In many cases, similar elements remain as impurities.
For example, in the case of iron which is a transition metal, many elements such as nickel and cobalt which are also transition metals are included as impurities. When purifying these 3N-level crude metals, a high-purity liquid is produced and electrolysis is performed.

In such electrolysis, in order to obtain a metal having a high purity, it is necessary to use a method of ion exchange or solvent extraction capable of producing an electrolyte solution having a small amount of impurities. As described above, in the production of the electrolytic solution, it is usual that the electrolytic solution is purified before the electrolysis, and the operation for this has a disadvantage of increasing the cost.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrolysis and electrowinning method capable of efficiently producing a high-purity metal by effectively utilizing an electrode and an electrolyte produced in an electrolysis step. It is intended. Further, the present invention can reduce the oxygen content due to organic substances, and can also contain alkali metal elements such as Na and K, U and Th.
Radioactive elements such as F
An object of the present invention is to provide a method for purifying a metal that can effectively remove transition metals or heavy metal elements such as e, Ni, Cr, and Cu.

[0005]

In order to solve the above-mentioned problems, an electrolytic solution obtained by electrolyzing a primary electrodeposited metal obtained in a primary electrolytic process as an anode is used, and the electrolytic solution is subjected to electrolytic sampling or a plurality of electrolytic processes. By further purifying and electrolytically collecting, it is possible to simplify the preparation of the electrolytic solution and obtain a metal of higher purity, and further reduce the oxygen content due to organic matter by purifying the electrolytic solution. I learned that I can do it. Based on this finding, the present invention provides: A step of obtaining a primary electrodeposited metal by electrolyzing a crude metal raw material by primary electrolytic refining, electrochemically dissolving or acid dissolving the primary electrodeposited metal obtained by the primary electrolytic step as an anode,
1. A method for purifying a metal, comprising: a step of obtaining a high-purity electrolytic solution; and a step of obtaining a high-purity metal by electrolytic sampling from the high-purity electrolytic solution. 2. A step of obtaining a primary electrodeposited metal by electrolyzing a crude metal material by primary electrolytic refining, and obtaining a highly pure secondary electrolytic solution by electrochemically dissolving or dissolving an acid using the primary electrodeposited metal obtained by the primary electrolytic step as an anode. A step of using a highly pure electrolytic solution for secondary electrolysis and a step of secondary electrorefining using the primary electrodeposited metal as an anode, and electrochemically dissolving or acid dissolving the electrodeposited metal obtained in the electrolytic step as an anode. A method for obtaining a high-purity metal by subjecting the high-purity electrolytic solution to primary or several-order electrowinning from the high-purity electrolytic solution. 3. A step of electrochemically dissolving or dissolving the acid by using the pre-deposited metal obtained in the pre-electrolysis step as an anode to obtain a highly pure secondary electrolyte, using the highly pure electrolytic solution for the secondary electrolysis, and converting the pre-deposited metal to an anode; 3. The method for purifying a metal according to the above item 2, wherein a plurality of order electrolysis steps are performed. 4. 4. The method for purifying a metal according to any one of the above 1 to 3, wherein the metal is subjected to electrolytic refining after electrowinning. 5. 5. The method for purifying a metal according to the above 3 or 4, wherein the electrolytic refining and the electrowinning are repeated alternately or intermittently. 6. The electrolytic solution is circulated through an activated carbon tank to remove organic substances in the high-purity metal aqueous solution, and the oxygen content due to the organic substances and 30 ppm or less of the metal according to any of the above 1 to 5, High purification method. 7. The crude metal has a purity of 3N or less, the primary electrodeposited metal has a purity of 3N to 4N excluding gas components such as oxygen, and the high purity metal obtained by electrolytic refining and electrowinning has a purity of 4N to 5N or more. 7. The method for purifying a metal according to any one of the above items 1 to 6. 8. The crude metal has a purity of 4N or less, the primary electrodeposited metal has a purity of 4N to 5N excluding gas components such as oxygen, and the high-purity metal obtained by electrolytic refining and electrowinning has a purity of 5N to 6N or more. 7. The method for purifying a metal according to any one of the above items 1 to 6. 9. The content of alkali metal elements such as Na and K in the high-purity metal is 1 ppm or less in total, and the content of radioactive elements such as U and Th is 1 ppb or less in total, Fe, Ni, C
Transition metals or heavy metal elements such as r and Cu are 10p in total
pm or less, the balance being a metal to be purified and other unavoidable impurities, the method for purifying a metal according to any one of the above items 1 to 8, 10. C content is 30ppm or less and S content is 1p
pm or less, wherein the metal is highly purified. 11. The high-purity metal obtained by electrolytic sampling or electrolytic refining is further melted in a vacuum or Ar atmosphere or Ar-H
11. The method for purifying a metal according to any one of the above items 1 to 10, wherein the metal is dissolved in _two atmospheres. Is provided.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to FIG. FIG. 1 shows an outline of the primary electrolysis step, the electrolytic solution production step for electrolysis, and the electrowinning step. As shown in FIG. 1, in a primary electrolytic cell 1, a raw material (3N or less or 4N or less) metal 3 such as metal scrap is put in an anode basket 2 and the crude metal material is electrolyzed to deposit a primary electrodeposited metal on a cathode 4. Precipitate. Reference numeral 5 denotes an anode for primary electrolysis. in this case,
The first electrolyte is prepared beforehand. The purity of the primary electrodeposited metal obtained by the primary electrolytic refining is 3N to 4N or 4N to 5N.

Next, as the electrodeposited metal anode, an electrolytic solution 8 for electrowinning is obtained by electrochemical dissolution or acid dissolution, and in FIG. Is shown. The cathode 11 in the electrolytic solution production tank 9 is shut off using an anion exchange membrane so that the metal from the anode 10 does not precipitate. When dissolving in acid, the primary electrodeposited metal is dissolved in acid and the pH is adjusted to obtain a highly pure electrolytic solution. The electrolytic solution 8 thus produced is supplied to the cathode box 1 of the electrolytic refining tank 12 shown in FIG.
3 to obtain a highly pure electrodeposited metal by electrowinning.
An insoluble anode is used as the anode 14. The cathode box 13 is partitioned by the anion exchange membrane 7. By this electrowinning, a product having a purity of 5N level or 6N level can be obtained relatively easily. Reference numeral 16 denotes a cathode in the cathode box 13.

[0008] If the desired purity cannot be obtained by further increasing the purity or by the above-mentioned primary electrolytic refining and electrowinning, secondary or higher electrolysis can be performed. For example, a tertiary electrolytic solution obtained by using a secondary electrodeposited metal deposited on a cathode by secondary electrolysis as an anode of a tertiary electrolytic cell (not shown) and using the secondary electrodeposited metal as an anode is produced. Is used as an electrolytic solution in the tertiary electrolytic cell to deposit a tertiary electrodeposited metal on the cathode of the tertiary electrolytic cell. In this way, the purity of the deposited metal is successively improved. In the above description, the final step is electrolytic refining. However, electrolytic refining can be performed after electrolytic retrieving, or electrolytic refining and electrolytic retrieving can be repeated alternately or intermittently. Electrolytic refining and electrowinning are similar to those described in the above steps.

[0009] The electrolytic solution used in each electrolysis step is circulated through an activated carbon tank to remove organic substances in the high-purity metal aqueous solution, so that the oxygen content due to the organic substances can be reduced to 30 ppm or less. Furthermore, high-purity metal obtained by electrolytic extraction or electrolyte further dissolved in a vacuum melting or Ar atmosphere or Ar-H ₂ atmosphere, it is possible to increase the purity. As a result, the total content of alkali metal elements such as Na and K in the high-purity metal is 1 ppm or less in total, U, Th
The total content of radioactive elements such as 1 ppb or less, F
Transition metals or heavy metal elements such as e, Ni, Cr, and Cu can be 10 ppm or less in total, and the remainder can be highly purified metals and other unavoidable impurities. Furthermore, C content is 30 ppm or less and S content is 1 ppm.
It can be: Electrolysis and electrowinning of the present invention, iron, cadmium, zinc, copper, manganese, cobalt,
The present invention is applicable to electrowinning of metal elements such as nickel, chromium, silver, gold, lead, tin, indium, bismuth, and gallium.

[0010]

Examples and Comparative Examples Next, examples of the present invention will be described. This embodiment is merely an example, and the present invention is not limited to this example. That is, all aspects or modifications other than the examples are included within the scope of the technical idea of the present invention.

Example 1 Using an electrolytic cell as shown in FIG. 1, electrolytic refining was performed using 3N-level massive iron as an anode and 4N-level iron as a cathode. Bath temperature is 5
Electrolysis was performed at 0 ° C., a hydrochloric acid-based electrolyte at pH 2, an iron concentration of 50 g / L, and a current density of 1 A / dm ² . Thus, electrolytic iron (precipitated on the cathode) having a current efficiency of 90% and a purity of 4N was obtained. Next, this electrolytic iron was dissolved in a mixed solution of hydrochloric acid and hydrogen peroxide solution, and the pH was adjusted with ammonia to obtain an electrolytic solution for electrolytic collection, and electrolytic collection was performed. The electrolysis conditions are
A bath temperature of 50 ° which is the same as the electrolysis condition of the primary electrolysis.
C, electrolysis was performed with a hydrochloric acid-based electrolyte at a pH of 2 and an iron concentration of 50 g / L. As a result, electrolytic iron having a current efficiency of 92% and a purity of 5N was obtained. Table 1 shows the results of analysis of primary electrolytic iron and electrolytic iron obtained by electrolytic sampling. In the primary electrolytic iron, Al:
3 ppm, As: 5 ppm, Co: 5 ppm, Ni: 6
ppm, Cu: 1 ppm and S: 2 ppm are present as impurities.
Except for the presence of ppm, all others were below 1 ppm. Also, the used electrolytic solution could be returned to the primary electrolytic solution and used. As described above, excellent results were obtained in that high-purity (5N) iron could be produced by one electrolytic refining and subsequent electrolytic extraction, and that the production of the electrolytic solution was easy.

[0012]

[Table 1]

Example 2 In the same manner as in Example 1 described above, electrolysis was carried out using an electrolytic cell as shown in FIG. 1 and using cadmium in the form of 3N-level massive cadmium as an anode and titanium as a cathode. Electrolysis was performed at a bath temperature of 30 ° C., sulfuric acid of 80 g / L, cadmium concentration of 70 g / L, and current density of 1 A / dm ² . As a result, electrolytic cadmium (deposited on the cathode) having a current efficiency of 85% and a purity of 4N was obtained. Next, this electrolytic cadmium was electrolyzed in a sulfuric acid bath to obtain an electrolytic solution for electrolytic collection. Electrolytic sampling was performed using this electrolytic solution. The electrolysis conditions are the same as the electrolysis conditions of the primary electrolysis.
The electrolysis was carried out at 80 ° C., sulfuric acid 80 g / L, cadmium concentration 70 g / L, and current density 1 A / dm ² . As a result, electrolytic cadmium having a current efficiency of 92% and a purity of 5N was obtained.
Table 2 shows the analysis results of the primary electrolytic cadmium and the cadmium after the electrolytic collection. In the primary electrolytic cadmium, Ag: 1
ppm, Pb: 7 ppm, Cu: 1 ppm, Fe: 30
ppm is present as an impurity, but after electrowinning, P
Except for b: 1 ppm and Fe: 4 ppm, impurities were all less than 1 ppm. Example 1
Similarly to the above, the used electrolytic solution could be returned to the primary electrolytic solution and used. As described above, high purity (5
The excellent result that the cadmium of N) can be produced by one electrolytic refining and subsequent electrolytic extraction, and that the production of the electrolytic solution is easy was obtained.

[0014]

[Table 2]

Example 3 In the same manner as in Example 1 described above, electrolysis was carried out using an electrolytic cell as shown in FIG. 1 using a 3N level bulk cobalt as an anode and a 4N level cobalt as a cathode. . Bath temperature is 40 ° C, pH is 2 with hydrochloric acid electrolyte, cobalt concentration is 100g / L, current density is 1A / d
m ² , electrolysis time was 40 hours. As a result, about 1 kg of electrolytic cobalt (deposited on the cathode) was obtained with a current efficiency of 90%. Purity achieved 4N. Next, this electrolytic cobalt was dissolved with hydrochloric acid and adjusted to pH 2 with ammonia to obtain an electrolytic solution for electrolytic collection. Electrolytic sampling was performed using this electrolytic solution. The electrolysis conditions were the same as the electrolysis conditions for the primary electrolysis, that is, electrolysis was performed at a bath temperature of 40 ° C., a hydrochloric acid-based electrolyte at pH 2, and a cobalt concentration of 100 g / L. As a result, electrolytic cobalt having a current efficiency of 92% and a purity of 5N was obtained. Table 3 shows the results of the analysis of the primary electrolytic cobalt and the cobalt after the electrolytic extraction. In the raw material cobalt, Na: 15 ppm, K:
2 ppm, Fe: 8 ppm, Ni: 460 ppm, C
u: 1.5 ppm, Al: 2.5 ppm, Cr: 0.5
ppm, S: 1 ppm, U: 0.3 ppb, Th: 0.
2ppb exists as an impurity, but in the primary electrolysis, F
e: Except that 4 ppm and Ni: 35 ppm remained, the others were 0.1 ppm or less. In the electrowinning, only 1.5 ppm of Fe and 4 ppm of Ni remained, and the others were less than 0.1 ppm, and the impurities were greatly reduced. The used electrolyte could be returned to the primary electrolyte and used. As described above, high purity (5N) cobalt could be produced by one electrolytic refining and subsequent electrolytic extraction.

[0016]

[Table 3]

(Example 4) In the same manner as in Example 1 described above, electrolysis was performed using an electrolytic cell as shown in FIG. 1 and using 4N level nickel as a cathode and 4N level nickel as a cathode. . Bath temperature is 40 ° C, pH is 2 with sulfuric acid electrolyte, nickel concentration is 50g / L, current density is 1A / dm
^{2. The} electrolysis time was 40 hours. As a result, about 1 kg of electrolytic nickel (deposited on the cathode) was obtained with a current efficiency of 90%. Purity achieved 5N. Next, this electrolytic nickel was dissolved with sulfuric acid and adjusted to pH 2 with ammonia to obtain an electrolytic solution for electrolytic collection. Electrolytic sampling was performed using this electrolytic solution. The electrolysis conditions were the same as the electrolysis conditions of the primary electrolysis, that is, electrolysis was performed at a bath temperature of 40 ° C., a sulfuric acid-based electrolyte at pH 2, and a nickel concentration of 50 g / L. As a result, the current efficiency 92
% Of electrolytic nickel having a purity of 6N was obtained. Table 4 shows the results of the analysis of the primary electrolytic nickel and the nickel after electrowinning. In the raw material nickel, Na: 25 ppm, K: 1.2
ppm, Fe: 10 ppm, Co: 1.0 ppm, C
u: 1.5 ppm, Al: 0.5 ppm, Cr 0.2 p
pm, S: 2 ppm, U: 0.3 ppb, Th: 0.2
ppb exists as an impurity, but in the primary electrolysis, Fe:
4 ppm, except that Co: 0.2 ppm remains
All others were 0.1 ppm or less. Then, only 0.5 ppm of Fe remained by electrowinning, and all the others were less than 0.1 ppm, and the impurities were greatly reduced.
The used electrolyte could be returned to the primary electrolyte and used. As described above, high-purity (6N) nickel can be produced by one electrolytic refining and subsequent electrolytic extraction, and an excellent result that the production of the electrolytic solution is easy was obtained.

[0018]

[Table 4]

Example 5 Primary electrolytic refining and electrowinning were separately performed using a 4N-level raw material cobalt different from that used in Example 3, and at this time, the electrolytic solution was circulated through an activated carbon tank to increase Organic substances in the pure metal aqueous solution were removed.
Table 5 shows the analysis results of the impurity elements obtained by the purification in this case. As a result of the primary electrolysis and the electrowinning, the impurities contained in the electrolytic cobalt exceeded 0.6 ppm, Ti: 0.6 ppm, Fe: 1.6 ppm, Ni:
Only 3.8 ppm remained, except for gas components such as oxygen. In addition, although oxygen is not shown in the table, it was significantly removed by activated carbon, and it became 30 ppm or less. As shown above, high purity (5N) cobalt could be produced by one electrolytic refining followed by electrolytic harvesting.

[0020]

[Table 5]

Example 6 Electrorefining was performed using a 3N-level massive iron different from Example 1 as an anode and 4N-level iron as a cathode. The electrolysis conditions were as in Example 1.
Is the same as Thereby, 4N level electrolytic iron (precipitated on the cathode) was obtained. Next, electrolytic refining was performed using this electrolytic iron as an anode to obtain 5N-level electrolytic iron. And
The 5N-level electrolytic iron was dissolved with an acid, and the pH was adjusted to obtain an electrolytic solution, and electrowinning was performed. As a result, the purity is 5-6N.
Level of electrolytic iron was obtained. Table 6 shows the analysis results of the primary electrolytic iron, the secondary electrolytic iron, and the electrolytic iron obtained by electrolytic sampling. In the primary electrolytic iron, Al: 4.5 ppm, As: 6 ppm, C
o: 9 ppm, Ni: 10 ppm, Zn: 3 ppm, C
u: 2 ppm, S: 3 ppm exist as impurities, and in the secondary electrolytic iron, Al: 1 ppm, As: 1.2 ppm,
Co: 3.5 ppm, Ni: 2.5 ppm, Cu: 0.
5 ppm, S: reduced to 1 ppm, and after electrowinning,
All were less than 1 ppm. As described above, the result was that high-purity (5 to 6N) iron could be produced by two electrolytic purifications and subsequent electrolytic extraction.

[0022]

[Table 6]

[0023]

As described above, the electrolytic solution is produced by electrolyzing the primary electrodeposited metal as an anode, and the electrolytic solution is used for electrowinning to obtain 5N to 6N.
It has an excellent feature that it is possible to obtain a metal having a high purity at a level, and it is possible to reduce the manufacturing cost of an electrolytic solution having a level of 4N to 5N. In addition, there is a remarkable effect that the purity can be further improved by repeating electrorefining and electrowinning as needed.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a primary electrolysis process, an electrowinning process, and a manufacturing process of an electrolysis electrolysis solution.

[Description of Signs] 1 Primary electrolysis tank 2 Anode basket 3 Raw material metal 4, 11, 16 Cathode 5 Anode for primary electrolysis 7 Anion exchange membrane 8 Electrolyte for electrowinning 9 Electrolyte production tank 10 Anode 12 Electrolysis purification tank 13 Cathode box 14 Insoluble anode

[Procedure amendment]

[Submission date] April 11, 2001 (2001.4.1
1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

Next, as the electrodeposited metal anode, an electrolytic solution 8 for electrowinning is obtained by electrochemical dissolution or acid dissolution, and in FIG. Is shown. The cathode 11 in the electrolytic solution production tank 9 is shut off using an anion exchange membrane so that the metal from the anode 10 does not precipitate. When dissolving in acid, the primary electrodeposited metal is dissolved in acid and the pH is adjusted to obtain a highly pure electrolytic solution. The electrolytic solution 8 thus produced is put into the cathode box 13 of the electrolytic cell 12 in FIG. 1, and a high purity electrodeposited metal is obtained by electrolytic sampling. An insoluble anode is used as the anode 14. The cathode box 13 is partitioned by the anion exchange membrane 7. By this electrowinning, a product having a purity of 5N level or 6N level can be obtained relatively easily. Reference numeral 16 denotes a cathode in the cathode box 13.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

Example 6 Electrorefining was performed using a 3N-level massive iron different from Example 1 as an anode and 4N-level iron as a cathode. The electrolysis conditions were as in Example 1.
Is the same as Thereby, 4N level electrolytic iron (precipitated on the cathode) was obtained. Next, electrolytic refining was performed using this electrolytic iron as an anode to obtain 5N-level electrolytic iron. And
The 5N-level electrolytic iron was dissolved with an acid, and the pH was adjusted to obtain an electrolytic solution, and electrowinning was performed. As a result, the purity is 5-6N.
Level of electrolytic iron was obtained. Table 6 shows the analysis results of the primary electrolytic iron, the secondary electrolytic iron, and the electrolytic iron obtained by electrolytic sampling. In the primary electrolytic iron, Al: 4.5 ppm, As: 6 ppm, C
o: 9 ppm, Ni: 10 ppm, Zn: 3 ppm, C
u: 2 ppm, S: 3 ppm exist as impurities, and in the secondary electrolytic iron, Al: 1 ppm, As: 1.2 ppm,
Co: 3.5 ppm, Ni: 2.5 ppm, Cu: 0.
5 ppm, S: reduced to 1 ppm, and after electrowinning,
All were less than 1 ppm. As described above, the result was that high-purity (5 to 6N) iron could be produced by two electrolytic purifications and subsequent electrolytic extraction.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a primary electrolysis process, an electrowinning process, and a manufacturing process of an electrolysis electrolysis solution.

[Description of Signs] 1 Primary electrolysis tank 2 Anode basket 3 Raw material metal 4, 11, 16 Cathode 5 Anode for primary electrolysis 7 Anion exchange membrane 8 Electrolyte for electrowinning 9 Electrolyte production tank 10 Anode 12 Electrolysis tank 13 Cathode box 14 Insoluble anode

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4K001 AA01 AA04 AA05 AA06 AA07 AA08 AA09 AA10 AA11 AA15 AA16 AA19 AA20 AA21 AA30 BA23 EA02 EA03 4K058 AA12 BA17 BA18 BA25 BB03 BB04 DD22 EC07

Claims (11)

[Claims] 1. A step of obtaining a primary electrodeposited metal by electrolyzing a crude metal raw material by primary electrolytic refining, and electrochemically dissolving or acid dissolving the primary electrodeposited metal obtained in the primary electrolysis step as an anode to obtain high purity. A method for purifying a metal, comprising a step of obtaining an electrolytic solution and a step of obtaining a high-purity metal by electrolytic sampling from the high-purity electrolytic solution. 2. A step of obtaining a primary electrodeposited metal by electrolyzing a crude metal raw material by primary electrolytic refining, and electrochemically dissolving or acid dissolving the primary electrodeposited metal obtained by the primary electrodeposition step as an anode. A step of obtaining a secondary electrolytic solution, a step of using the high-purity electrolytic solution for the secondary electrolysis, and a step of performing secondary electrolytic purification using the primary electrodeposited metal as an anode, and using the electrodeposited metal obtained in the electrolytic step as an anode to perform electrochemical purification. 1. A method for purifying a metal, comprising: a step of obtaining an electrolytic solution by subjecting the solution to acid or acid dissolution; and a step of obtaining a high-purity metal by primary or several times of electrowinning from the high-purity electrolytic solution. 3. A step of electrochemically dissolving or dissolving an acid using the pre-deposited metal obtained in the pre-electrolysis step as an anode to obtain a high purity secondary electrolyte, using a high purity electrolytic solution for the next electrolysis, and 3. The method for purifying a metal according to claim 2, wherein a number-order electrolysis is carried out, comprising a step of electrolyzing the electrodeposited metal as an anode. 4. The method for purifying a metal according to claim 1, wherein electrolytic refining is performed after the electrowinning. 5. The method for purifying a metal according to claim 3, wherein the electrorefining and the electrowinning are repeated alternately or intermittently. 6. The method according to claim 1, wherein the electrolyte is circulated through an activated carbon tank to remove organic substances in the high-purity metal aqueous solution, and to reduce the oxygen content due to the organic substances to 30 ppm or less. A method for purifying the metal described in each of them. 7. The crude metal has a purity of 3N or less, the primary electrodeposited metal has a purity of 3N to 4N excluding gas components such as oxygen, and the high purity metal obtained by electrolytic refining and electrolytic sampling is 4N.
7. The composition according to claim 1, which has a purity of at least 5 N.
The method for purifying a metal according to any one of the above. 8. The crude metal has a purity of 4N or less, the primary electrodeposited metal has a purity of 4N to 5N excluding gas components such as oxygen, and the high-purity metal obtained by electrolytic refining and electrowinning has a purity of 5N.
7. The composition according to claim 1, which has a purity of at least 6 N.
The method for purifying a metal according to any one of the above. 9. The total content of alkali metal elements such as Na and K in a high purity metal is 1 ppm or less, the content of radioactive elements such as U and Th is 1 ppb or less in total, Fe, N
The transition metal or heavy metal element such as i, Cr, or Cu in total is 10 ppm or less, and the balance is a metal to be highly purified and other unavoidable impurities. High purification method. 10. The method according to claim 1, wherein the C content is 30 ppm or less and the S content is 1 ppm or less.
The method for purifying a metal according to any one of the above. 11. The high-purity metal obtained by electrowinning or electrorefining is further melted in a vacuum or in an Ar atmosphere or an Ar—H ₂ atmosphere.
10. The method for purifying a metal according to any one of items 10 to 10.