WO2003097903A1

WO2003097903A1 - Method and device for producing high-purity metal

Info

Publication number: WO2003097903A1
Application number: PCT/JP2003/001113
Authority: WO
Inventors: Yuichiro Shindo; Kouichi Takemoto
Original assignee: Nikko Materials Company, Limited
Priority date: 2002-05-21
Filing date: 2003-02-04
Publication date: 2003-11-27
Also published as: TW200307060A; TWI252875B; JP2004043946A

Abstract

A method of producing a high-purity metal characterized by comprising the step of, when metal-containing solution is used as an electrolyte in electrolyzing, partitioning an anode from a cathode by an negative ion exchange membrane, intermittently or continuously extracting an anolyte for introduction into a solvent extraction tank, and intermittently or continuously introducing toward the cathode a high-purity metal electrolyte having impurities such as iron removed in the solvent extraction tank. A simple method of effecting electrolysis from a metal material containing large amounts of iron, carbon and oxygen by using a metal-containing solution, the method capable of efficiently producing a high-purity metal having a purity of at least 4N (99.99 wt.%) or at least 5N (99.999 wt.%).

Description

Description Manufacturing method and equipment for high-purity metal

The present invention relates to a method and an apparatus for producing a high-purity metal by electrolytic extraction, which can dissolve and extract a raw material metal using a single electrolytic cell. Background art

Generally, high-purity metals such as nickel, cobalt, iron, indium, and copper are required to reduce alkali metals, radioactive elements, transition metal elements, and gas components as much as possible. It is widely used, especially as a sputtering target material, for forming compound semiconductors or magnetic thin films.

Alkali metals such as Na and K easily move in the gate insulating film and cause deterioration of the MOS-LSI interface characteristics. Radioactive elements such as U and Th cause the soft error of the device due to the emitted α-rays.

On the other hand, when materials such as nickel, cobalt, and copper are used as wiring materials for semiconductors, etc., that is, depending on the place where they are used, transition metal elements such as Fe may cause troubles at interface junctions. .

Further, it is said that gas components such as carbon and oxygen are also undesirable because they cause particles to be generated during sputtering.

Generally, when producing high-purity metals such as nickel, cobalt, iron, indium, and copper at the 5N level, the solution is purified by ion exchange or solvent extraction, and then purified by electrowinning or electrolytic refining. However, such a method of preceding the solvent extraction step has a problem that the step is complicated and requires a special solvent, so that it is not efficient. Also, when producing high-purity metals such as nickel, cobalt, iron, indium, and copper at the 5N level, it is considered to be a relatively simple method to produce them by electrolysis using these metal-containing solutions. However, for example, when attempting to produce high-purity nigels by electrolysis, separation was difficult due to the large amount of other metal elements (mainly iron) contained in the electrolyte, which was not always efficient. Disclosure of the invention

The present invention provides a simple method of electrolyzing a metal raw material such as nickel, cobalt, iron, indium, and copper containing a large amount of other metal elements, carbon, oxygen, and the like, using the metal-containing solution. The purpose of the present invention is to provide a technology for efficiently producing a high-purity metal having a purity of 5 N (99.99.99 wt%) or more from the same raw material.

In order to solve the above-mentioned problems, other metal elements and other impurities are removed from the anolyte of the metal-containing solution by solvent extraction, and the liquid after the removal is used as catholyte to efficiently and highly purify the metal. The knowledge that can be manufactured.

Based on this finding, the present invention

1. When performing electrolysis using a solution containing a metal for purification as an electrolyte, the anode and cathode are separated by an anion exchange membrane, and anolyte is extracted intermittently or continuously and introduced into a solvent extraction tank. A method for producing a high-purity metal, characterized in that impurities are removed in the solvent extraction tank, and the high-purity metal electrolyte solution after the removal of the impurities is intermittently or continuously introduced into a power source side.

2. The method for producing a high-purity metal as described in 1 above, wherein the melting of the metal raw material and the collection of the metal are simultaneously performed in a single electrolytic cell, and the metal is separated by an ion exchange membrane. 3. The high-purity metal electrolyte from which impurities have been removed in a solvent extraction tank is temporarily stored, and the high-purity metal electrolyte is intermittently or continuously introduced into the cathode side. Of high purity metal

4. The method for producing a high-purity metal according to any one of the above items 1 to 3, wherein the anolyte and the catholyte are circulated.

Is provided.

The present invention also provides

5. High-purity metal production equipment by electrolysis, including an anode basket containing metal raw materials, an anion-exchange membrane separating the anode and the power source, a cathode for depositing high-purity metal, and impurities from the metal solution (anolyte). A solvent extraction tank, a device that intermittently or continuously withdraws anolyte and introduces it into the solvent extraction tank, and intermittently or continuously introduces the high-purity metal electrolyte obtained by solvent extraction to the cathode side High-purity metal characterized by comprising a device

6. The apparatus for producing a high-purity metal as described in 5 above, wherein the dissolution of the metal raw material and the collection of the metal are performed in a single electrolytic cell and separated by an ion exchange membrane.

7. The high-purity gold according to the above item 5 or 6, further comprising an electrolyte storage tank for temporarily storing the high-purity metal electrolyte from which impurities have been removed in the solvent extraction tank.

8. The apparatus for producing a high-purity metal according to any one of the above items 5 to 7, further comprising an apparatus for circulating a liquid of ananolite and a catholyte.

Is provided. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram showing an outline of the electrolysis process. Embodiment of the Invention

Using an electrolytic cell 1 shown in Fig. 1, a bulk metal material 2 of 4 N level is put into an anode basket 3 to form an anode 5, and a metal similar to the highly purified metal or another metal material is used for a force sword 4. Perform electrolysis. Metal raw materials contain many impurities such as metal elements, carbon, oxygen, etc., other than those of high purity. In electrolysis varies depending metal electrolyte, generally the bath temperature 1 0 to 7 0 C, the metal concentration 2 0~: L 2 0 gZL, carried out at a current density 0. 1~ 1 0 AZdm ^2. If the current density is low, for example, less than 0.1 A / dm ² , the productivity will be poor, and if it is too high, for example, if it exceeds 10 AZdm ² , nodules will tend to occur. Therefore, it is usually desirable that the current density be in the range of 0.1 to 10 A / dm ² .

However, since the conditions can be changed depending on the metal to be electrolyzed as described above, it is not always necessary to limit to the above range.

The anode 5 and the force sword 4 are separated by an anion exchange membrane 6, and intermittently or continuously extracted while circulating an anolyte 7. Catholyte is separated from the outer liquid (anolyte) via the anion exchange membrane 6. The extracted anolyte 7 is introduced into a solvent extraction tank 8.

In the solvent extraction tank 8, other metal elements and other impurities in the electrolytic solution are removed. As a result, the concentration of other metal elements in the electrolyte can be reduced to approximately 1 mg / L or less.

After the solvent extraction, the highly purified metal electrolyte is introduced intermittently or continuously into the power source side, and used as catholyte 9 for electrolytic sampling.

After the solvent extraction, the highly purified metal electrolyte may be applied to a filter (not shown) such as activated carbon, if necessary. The activated carbon filter has an effect of removing impurities from an organic solvent or an organic substance derived from an ion exchange membrane.

An electrolyte storage tank 9 for temporarily storing a high-purity metal electrolyte from which impurities such as other metal elements have been removed in a solvent extraction tank is provided and circulated. In this case, the highly purified metal electrolyte after the solvent extraction is once stored in the electrolyte storage tank 9, and then intermittently or continuously introduced into the power source from there, and used as the catholyte 9. Collect.

The current efficiency is 80 to 100%. As a result, an electrodeposited metal having a purity of 5 N or more (precipitated on a power source) can be obtained. That is, excluding gas components, it is 4 N (99.99 wt%) or more, depending on the material, it is 5 N (99.999 wt%) or more, and O: 100 wt ppm or less as an impurity (depending on the material). Is 0: 3 O wtppm or less), and each of C, N, S, and H can be set to 10 wtppm or less.

Further, the electrodeposited metal obtained by electrolysis can be subjected to vacuum melting such as electron beam melting. By this vacuum melting, alkali metals such as Na and K and other volatile impurities and gas components can be effectively removed. 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, within the scope of the technical idea of the present invention, all aspects or modifications other than the examples are included ₍ (Example 1)

Using an electrolytic cell as shown in Fig. 1, electrolysis was performed using 1 kg of 3N-level massive nickel raw material as an anode and a 2N-level nickel plate as a power source. Table 1 shows the content of impurities in the raw materials. Nickel raw materials mainly contain large amounts of iron, carbon, oxygen, and the like. Bath temperature 50 ° (:.., Using a sulfuric acid-based electrolyte, pH 2, was carried out at a current density of 2A / dm ² electrolysis Initially, N i concentration in the anode side is 20 GZL After the electrolysis, N i concentration 100 GZL Extract as

The extracted anolyte was introduced into a solvent extraction tank. Further, impurities such as this precipitate were removed using an activated carbon filter. Thus, the concentration of iron in the electrolyte could be reduced to 1 mg / L or less.

After removing the impurities, this solution was intermittently introduced into the power source side, and used as catholyte for electrowinning. The Ni concentration on the force side is 100 gZL, but the Ni concentration after electrolysis is 20 gZL.

Electrodeposited nickel (deposited on a force sword) About lkg was obtained. Purity achieved 5N. That is, it was 5N (99.999 wt%) or more, excluding gas components, O: 30 wt ppm or less as impurities, and C, N, S, respectively, could be 10 wt ppm or less. The above results are compared with the raw materials, and w t p p m

(Comparative Example 1)

An electrolytic cell as shown in Fig. 1 was used. However, no anion exchange membrane was used and no solvent extraction was performed.

Then, electrolysis was performed using 1 kg of a 3N-level massive nickel raw material as an anode and a 2N-level nickel plate as a power source. Table 1 shows the content of impurities in the raw materials. The bath temperature was 50 ° (: using a sulfuric acid-based electrolyte, the nickel concentration was 60 g / L, and the current density was 2 AZ dm ² .

The pH of the solution was adjusted for 2. At this time, electrolysis was continued without extracting anolyte. Then, about 1 kg of electrodeposited nickel (deposited on a force sword) was obtained: The above results are also shown in Table 1.

As shown in Table 1, in Example 1, the raw material iron was 50 wtp pm to 2 wtp pm, oxygen was 200 wtp pm to less than 10 wtp pm, carbon was 50 wt ppm to less than 10 wt ppm, and N 10 wtppm or less, Slw tp pm or less, Na and K could each be less than 0.1 wtppm _c In contrast, in Comparative Example 1, C and N were each less than 10 wtp pm , S lw tp pm, and Na and K were each less than 0.1 lw tp pm, but iron 50 w tp pm, cobalt 20 w tp pm, oxygen 60 wt pm, and oxygen The purification effect was inferior to that of, and it was particularly difficult to remove iron and cobalt.

(Example 2)

As in Example 1, electrolysis was performed using an electrolytic cell as shown in Fig. 1, using 1 kg of 90 wt% pure cobalt scrap raw material as the anode, and using a 2N level cobalt plate as the power source. went. Table 2 shows the impurity contents of the raw materials. The cobalt raw material mainly contained a large amount of tungsten, titanium, iron, carbon, oxygen and the like.

Bath temperature 50 ° (: Using a sulfuric acid-based electrolyte, pH 2 and current density 2 A / dm ^2. At the beginning of electrolysis, the C 0 concentration on the anode side was 20 g / L. After electrolysis , With a CO concentration of 100 g / L.

The extracted anolyte was introduced into a solvent extraction tank. Further, impurities such as this precipitate were removed using an activated carbon filter. As described above, the concentration of metal element impurities such as iron and tungsten in the electrolyte could be reduced to 1 mgZL or less. After removal of the impurities, this solution was intermittently introduced to the power source side, and used as a catholyte for electrowinning. The Co concentration on the cathod side was 100 gZL, but the Co concentration after electrolysis was less than 20 g / L.

About lkg of deposited cobalt (precipitated on a force sword) was obtained. Purity achieved 5 N. That is, excluding gas components, it was 5 N (9.99.99 wt%) or more, and as impurities, 〇: l Ow tp pm or less, and C, N, and S could each be l Ow tp pm or less. . Table 2 shows the results compared with the raw materials.

w t p p m (other than% display) 2/1

wtppm (other than% display) 2/2

(Example 3)

As in Example 1, electrolysis was performed using an electrolytic cell as shown in FIG. 1, using 1 kg of a 2N-level massive iron raw material as an anode, and using a 2N-level iron plate as a power source. Table 3 shows the content of impurities in the raw materials. Iron raw materials mainly contained large amounts of aluminum, arsenic, boron, cobalt, chromium, nickel, zinc, copper, carbon, oxygen, and the like.

The test was performed at a bath temperature of 50 ° C., a sulfuric acid-based electrolyte, and at a pH of 2 and a current density of 2 A / dm ² . At the beginning of the electrolysis, the iron concentration on the anode side is 20 gZL. After electrolysis, extract with an iron concentration of 100 g / L. The extracted anolyte was introduced into a solvent extraction tank. Further, impurities such as this precipitate were removed using an activated carbon filter. As described above, the concentration of metal element impurities such as nickel and cobalt in the electrolyte could be reduced to 1 mg / L or less.

After removing the impurities, this solution was intermittently introduced into the power source side, and used as catholyte for electrowinning. The iron concentration on the force sword side was 100 g / L, but the iron concentration after electrolysis was less than 20 gZL each.

Electrodeposited iron (precipitated on a force sword) About lkg was obtained. Purity achieved 5 N. That is, except for gas components, the content is 5 N (99.99 wt%) or more, and as impurities, O: 20 w tp pm and C, N, and S can be each set to 10 wt pm or less. Was. Table 3 compares the above results with the raw materials.

Table 3

w t p p m

(Example 4)

As in Example 1, electrolysis was performed using an electrolytic cell as shown in FIG. 1, using 1 kg of indium scrap raw material having a purity of 90 wt% level as an anode, and using a 2 N level indium plate as a power source. went. Table 4 shows the content of impurities in the raw materials. The indium raw material mainly contained a large amount of bismuth, antimony, lead-iron, zinc, silver, copper, aluminum, carbon, oxygen, and the like. Bath temperature 5 0 ° C, using hydrochloric acid electrolytic solution, pH 2, was carried out at a current density 2AZdm ^2. At the beginning of electrolysis, the indium concentration on the anode side is 20 gZL ₍ after electrolysis, the indium concentration is extracted as 100 g / L. 0 The extracted anolyte was introduced into the solvent extraction tank. Further, impurities such as this precipitate were removed using an activated carbon filter. From the above, the concentration of metal element impurities in the electrolyte could be reduced to 1 mg / L or less.

After removal of the impurities, this solution was intermittently introduced to the power source side, and used as a catholyte for electrowinning. Although the indium concentration on the kaleid side was 100 gZL, the indium concentration after electrolysis was less than 20 gZL each. Electrodeposited indium (deposited on a force sword) was obtained in an amount of about lkg. Purity achieved 4 N. That is, excluding gas components, it was 4 N (9.99.9 wt%) or more, and 0: 20 wt p pm and C, N, and S, respectively, as impurities could be reduced to 10 wt p pm or less. Table 4 compares the above results with the raw materials.

Table 4

w t p p m (other than% display) 4/1

Bi Sb Pb Fe Cu Zn Mn Ag Al

In raw material 500 600 80 5¾ 1% 40 8 5 2%

Example 4 5 2 3 <1 2 1 <1 <1 <1 w t p pm (other than% display) 4Z2

0 C N s H

In raw material 1% 0.1% 100 0.1%

Example 4 20 10 10 10 10 (Example 5)

As in Example 1, electrolysis was performed using an electrolytic cell as shown in FIG. 1, using 1 kg of a 4 N-level pure copper raw material as an anode, and using a 2N-level copper plate as a power source. Table 5 shows the content of impurities in the raw materials. Copper raw materials mainly contained large amounts of iron, chromium, nickel, silver, aluminum, antimony, selenium, silicon, sulfur, oxygen, and the like.

The test was performed at a bath temperature of 50 ° C and a nitric acid-based electrolyte at a pH of 2 and a current density of 2 A / dm ² . At the beginning of electrolysis, the copper concentration on the anode side is 20 gZL. After electrolysis, extract with a copper concentration of 100 g / L.

The extracted anolyte was introduced into a solvent extraction tank. Further, impurities such as the precipitate were removed using an activated carbon filter. From the above, the concentration of metal element impurities in the electrolyte could be reduced to 1 mgZL or less.

After removal of the impurities, this solution was intermittently introduced to the power source side, and used as a catholyte for electrowinning. The copper concentration on the force sword side was 100 g / L, but the copper concentration after electrolysis was less than 20 gZL each.

Electrodeposited copper (deposited on force sword) Approximately lkg was obtained. Purity achieved 6N. That is, the content was 6 N (99.9999 wt%) or more, excluding gas components, and as impurities, 〇, S: lw tp pm or less, and C, N, S could each be 10 wt ppm or less. Table 5 compares the above results with the raw materials.

Table 5

w t p p m 5

Fe Cr Ni Ag Al Sb As Se Si

Cu raw material 20 1 2 4 5 7 4 8 2 Example 4 0.1 <0.1 <0.1 0.1 0.1 0.1 0.1 0.1 0.4 0.1 w t p p m 5 / '2

0 C N S H

Cu raw material 20 10 10 5 ku 10

Example 4 From the above, the anode and the force sword of the present invention were separated by an anion exchange membrane, and the anolyte was extracted intermittently or continuously. Removal of impurities such as elements, and further removal of impurities using a filter, and intermittently or continuously placing the removed liquid on the power source side for electrolytic sampling, remove impurities such as metal elements. It can be seen that this is a simple and very effective method for effectively removing and obtaining high-purity metals. The invention's effect

As shown above, a high-purity metal-containing solution is used as the electrolytic solution, and a metal raw material containing a large amount of other metal elements, non-metals, carbon, oxygen, etc., is used for electrowinning using the metal-containing solution for electrolysis. Purity 4 N (99.99 wt%) or 5 N (99.99 wt%) from the same raw material by improving the simple manufacturing process It has a remarkable effect that the above high-purity metals can be produced efficiently.

Claims

The scope of the claims

1. When performing electrolysis using a solution containing a metal for purification as an electrolytic solution, the anode and force sword are separated by an anion exchange membrane, and anolyte is extracted intermittently or continuously and introduced into a solvent extraction tank. And removing the impurities in the solvent extraction tank, and intermittently or continuously introducing the high-purity metal electrolyte from which the impurities have been removed to the power source side.

2. In a single electrolytic cell, the dissolution of the metal raw material and the collection of the metal are simultaneously performed, and the metal is separated by an ion-exchange membrane. Production method.

3. The high-purity metal electrolyte from which impurities have been removed in the solvent extraction tank is temporarily stored, and the high-purity metal electrolyte is intermittently or continuously introduced into the power source side. 3. The method for producing a high-purity metal according to item 1 or 2.

4. The method for producing a high-purity metal according to any one of claims 1 to 3, wherein the solution of anolyte and catholyte is circulated.

5. High-purity metal production equipment by electrolysis, including an anode basket containing metal raw materials, an anion exchange membrane separating the anode and the power sword, a power sword for precipitating high-purity metal, and a metal solution (anolite) Solvent extraction tank, equipment for extracting anolyte intermittently or continuously and introducing it into the solvent extraction tank, and intermittently or continuously the high-purity metal electrolyte obtained by solvent extraction toward the cathode side High-purity metal production equipment, characterized by the equipment to be introduced.

6. The apparatus for producing a high-purity metal according to claim 5, wherein the dissolution of the metal raw material and the collection of the metal are performed in a single electrolytic cell and are separated by an ion exchange membrane. .

7. The high-purity metal according to claim 5 or 6, further comprising an electrolyte storage tank for temporarily storing the high-purity metal electrolyte from which impurities have been removed in the solvent extraction tank. Manufacturing equipment.

8. The apparatus for producing a high-purity metal according to any one of claims 5 to 7, further comprising a device for circulating a liquid of the anolyte and the power solite.