JP6958235B2 - How to separate copper from nickel and cobalt - Google Patents

Description

The present invention relates to a method for separating copper, nickel and cobalt from an alloy containing copper, nickel and cobalt.

Vehicles such as electric vehicles and hybrid vehicles and electronic devices such as mobile phones, smartphones, and personal computers are equipped with lithium-ion batteries (hereinafter, also referred to as "LIB"), which are characterized by being lightweight and having high output. ..

The LIB is a negative electrode material in which a negative electrode active material such as graphite is fixed to the surface of a metal outer can such as aluminum or iron or a plastic outer can such as vinyl chloride using a copper foil as a negative electrode current collector. A positive electrode material in which a positive electrode active material such as lithium nickelate or lithium cobaltate is fixed to a positive electrode current collector made of aluminum foil is charged together with a separator made of a porous resin film of polypropylene or the like, and lithium hexafluoride phosphate is charged. It has a structure in which an organic solvent containing an electrolyte such as (LiPF _{6) is impregnated as an electrolytic solution.}

If the LIB is incorporated into a vehicle or electronic device as described above and used, it will eventually become unusable due to deterioration of the automobile or electronic device or the life of the LIB, resulting in a waste lithium ion battery (waste LIB). .. In addition, waste LIB may be generated as a defective product in the manufacturing process from the beginning.

These waste LIBs contain valuable components such as nickel, cobalt and copper, and it is desired to recover and reuse the valuable components in order to effectively utilize the resources.

Generally, when trying to efficiently recover valuable components from equipment, members and materials made of metal, they are put into a furnace, etc., all melted at high temperature, and separated into valuable metal and slag for disposal. It is considered that the dry process using the pyrometallurgical technique is quick.

For example, Patent Document 1 discloses a method of recovering a valuable metal by using a dry treatment. By applying the method of Patent Document 1 to waste LIB, a copper alloy containing nickel and cobalt can be obtained.

Although this dry treatment has a problem that it requires energy for heating to a high temperature, it has an advantage that various impurities can be treated in a simple process and separated at once. In addition, since the obtained slag has relatively stable chemical properties, there is no concern about causing environmental problems, and there is an advantage that it is easy to dispose of.

However, when the waste LIB is treated by the dry treatment, there is a problem that a part of valuable components, particularly most of cobalt, is distributed to the slag, resulting in a loss of cobalt recovery.

Further, the metal obtained by the dry treatment is an alloy in which valuable components coexist, and in order to reuse it, it is necessary to separate each component from this alloy and purify it to remove impurities.

As a method of element separation generally used in the dry method, there is a method of separating copper and lead or lead and zinc by slowly cooling from a high-temperature molten state. However, when copper and nickel are the main components as in waste LIB, copper and nickel have the property of uniformly melting over the entire composition range, so even if they are slowly cooled, copper and nickel are only mixed and solidified in layers. It cannot be separated.

Further, there is a purification method in which nickel is disproportionated using carbon monoxide (CO) gas to volatilize and separate it from copper or cobalt, but it is difficult to ensure safety because highly toxic CO gas is used.

Further, as a method for separating copper and nickel, which has been industrially performed, there is a method for coarsely separating a mixed mat (sulfide). In this method, a mat containing copper and nickel is produced in the smelting process, and the mat is slowly cooled in the same manner as described above to separate the sulfide containing a large amount of copper and the sulfide containing a large amount of nickel. Is. However, even with this method, the separation of copper and nickel is limited to a crude separation level, so there is a problem that a separate step such as electrolytic refining is required to obtain high-purity nickel or copper.

As another method, a method of utilizing the vapor pressure difference via chloride has been considered, but since it is a process of handling a large amount of toxic chlorine, it is an industrially suitable method for equipment corrosion countermeasures and safety measures. There was a problem that it was hard to say.

The same applies to the separation of copper and cobalt and the separation of cobalt and nickel.

As described above, the separation and purification of each element by the dry method as compared with the wet method has a drawback that the separation level remains at the crude separation level or the cost is high.

On the other hand, wet treatment using hydrometallurgy methods such as acid, neutralization, and solvent extraction consumes less energy, separates mixed valuable components individually, and directly recovers them with high-purity quality. There is a merit that it can be done.

However, when the waste LIB is treated by a wet treatment, the hexafluorophosphate anion contained in the waste LIB is a difficult-to-treat product that cannot be completely decomposed even with high-temperature and high-concentration sulfuric acid. Yes, the valuable components will be mixed in the leached acid solution. Furthermore, since this hexafluorophosphate anion is a water-soluble carbonic acid ester, it is difficult to recover phosphorus and fluorine from the aqueous solution after recovering valuable resources, and they are released to public sea areas by wastewater treatment. There is a problem that it becomes difficult to suppress.

In addition, it is not easy to obtain a solution capable of efficiently leaching valuable components from waste LIB and using it for purification with only an acid. The waste LIB itself is difficult to leached and the leaching rate of valuable components is insufficient, or if it is forcibly leached by using an acid with strong oxidizing power, not only the valuable components but also the components such as aluminum, iron and manganese that are not subject to recovery Is leached out in large quantities, and there is a problem that the amount of neutralizing agent added to treat these and the amount of wastewater to be handled increase.

Furthermore, when the pH of the liquid is adjusted to pass through separation means such as solvent extraction and ion exchange from the acidic leachate, or when impurities are neutralized and fixed to the starch, the amount of neutralized starch generated also increases. Therefore, there are many problems in terms of securing a processing place and ensuring stability.

Further, electric charges may remain in the waste LIB, and if it is treated as it is, it may cause heat generation or explosion, and it is necessary to take time-consuming measures such as immersing it in salt water and discharging it.

It is not always an advantageous method to treat the waste LIB using only the wet treatment as described above.

Therefore, a method of combining dry treatment and wet treatment for waste LIB, which is difficult to treat by the above-mentioned dry treatment or wet treatment alone, that is, a uniform waste LIB treatment in which impurities are removed as much as possible by dry treatment such as roasting waste LIB. Attempts have been made to make a product and wet-treat this treated product to separate it into valuable components and other components.

In the method combining the dry treatment and the wet treatment, fluorine and phosphorus in the electrolytic solution are removed by volatilizing by the dry treatment, and the organic members such as plastics and separators, which are the structural parts of the waste LIB, are decomposed.

However, after the dry treatment as described above, the problem of recovery loss caused by the distribution of cobalt contained in the waste LIB to the slag still remains.

A method of distributing cobalt as a metal by adjusting the atmosphere, temperature, degree of reduction, etc. in the dry treatment and reducing and melting the cobalt so as to reduce the distribution to the slag can be considered, but this time, the metal obtained by such a method. Will form a poorly soluble corrosion-resistant alloy containing nickel and cobalt based on copper, and there will be a problem that it will be difficult to dissolve even if it is dissolved with an acid in order to separate and recover valuable components.

Further, even if the above corrosion-resistant alloy is acid-dissolved using chlorine gas, for example, the obtained solution (leaching solution) contains a high concentration of copper and a relatively low concentration of nickel or cobalt. Of these, nickel and cobalt are not so difficult to separate using a known method such as solvent extraction. However, it has not been easy to separate a large amount of copper from nickel and cobalt at low cost.

As described above, it has been difficult to efficiently separate only copper, nickel, and cobalt from waste LIB containing various non-recoverable components in addition to the valuable components copper, nickel, and cobalt.

The above-mentioned problems also exist in the case of separating copper, nickel and cobalt from a waste battery containing copper, nickel and cobalt other than waste LIB, and copper and nickel derived from other than waste battery. The same is true when copper, nickel and cobalt are separated from an alloy containing cobalt.

Japanese Unexamined Patent Publication No. 2012-172169 Japanese Unexamined Patent Publication No. 63-259033

The present invention has been made in view of such circumstances, and copper, nickel, and cobalt, such as an alloy having high corrosion resistance containing copper, nickel, and cobalt, which are obtained by dry-treating a waste lithium ion battery, are used. It is an object of the present invention to provide a method for separating copper, nickel and cobalt, which can efficiently and selectively separate copper and nickel and cobalt from the containing alloy.

The present inventors have made extensive studies to solve the above-mentioned problems. As a result, by contacting an alloy containing copper, nickel and cobalt with a sulfuric acid solution containing chloride under the condition that a sulfide agent coexists, copper leached from the alloy containing copper, nickel and cobalt is copper sulfide. Since nickel and cobalt that have been precipitated as (solid) and leached can remain in the leachate, copper, nickel, and cobalt can be efficiently and selectively separated from the alloy containing copper, nickel, and cobalt. The present invention has been completed. That is, the present invention provides the following.

(1) In the first invention of the present invention, an alloy containing copper, nickel and cobalt is brought into contact with a chloride-containing sulfuric acid solution under the condition that a sulfide agent coexists, and the copper-containing solid and nickel are brought into contact with each other. And a method for separating copper, nickel and cobalt to obtain a leachate containing cobalt.

(2) In the second invention of the present invention, the sulfurizing agent is one or more selected from sulfur, hydrogen sulfide gas, sodium hydrogen sulfide and sodium sulfide. It is a separation method.

(3) In the third aspect of the present invention, the chloride-containing sulfuric acid solution and the sulfide agent are brought into contact with the alloy containing copper, nickel, and cobalt at the same time, or the sulfide agent is brought into contact with the alloy. The method for separating copper, nickel, and cobalt according to the first or second invention, wherein the sulfuric acid solution containing the chloride is brought into contact with the copper.

(4) The fourth invention of the present invention is the first to third inventions, wherein the alloy containing copper, nickel and cobalt is an alloy obtained by heating and melting scraps of a lithium ion battery and reducing them. The method for separating copper, nickel and cobalt according to any one of them.

(5) In the fifth invention of the present invention, the alloy containing copper, nickel and cobalt is a powder, and the particle size of the alloy containing copper, nickel and cobalt is 300 μm or less. The method for separating copper, nickel and cobalt according to any one of the fourth inventions.

(6) In the sixth aspect of the present invention, the copper-containing solid and the nickel-cobalt-containing leachate are separated, and then the copper remaining in the nickel-cobalt-containing leachate is removed. The method for separating copper, nickel, and cobalt according to any one of the fifth inventions.

(7) The seventh invention of the present invention is the sixth invention of removing copper remaining in the leachate containing nickel and cobalt by one or more methods selected from sulfurization, electrowinning and neutralization precipitation. The method for separating copper, nickel and cobalt according to the above.

According to the present invention, copper, nickel and cobalt can be efficiently and selectively separated from an alloy containing copper, nickel and cobalt. For example, a waste lithium ion battery is obtained by heating and melting and reducing it. Nickel and cobalt can be selectively separated from copper efficiently and selectively from the poorly soluble copper alloy containing nickel and cobalt.

Then, nickel and cobalt separated from the alloy according to the present invention can be separated by a known method and can be effectively reused as metals and salts of high-purity nickel and cobalt, respectively. In addition, copper separated from the alloy is in the form of a sulfide suitable for copper bricks, and high-purity copper can be recovered by directly putting it into a converter of a copper brick furnace or the like and subjecting it to means such as electrolytic refining. can.

It is a figure which shows the relationship between the reaction time and the leaching rate of nickel. It is a figure which shows the relationship between the reaction time and the leaching rate of cobalt. It is a figure which shows the relationship between the reaction time and the leaching rate of copper. It is a figure which shows the relationship between the amount of Cl in chloride contained in sulfuric acid, and the leaching rate of nickel, cobalt, and copper.

Hereinafter, embodiments of the present invention will be described. In this specification, the notation "X to Y" (X and Y are arbitrary numerical values) means "X or more and Y or less".

The method for separating copper, nickel and cobalt according to the present embodiment (hereinafter, simply referred to as “separation method”) is derived from an alloy containing copper, nickel and cobalt (hereinafter, also simply referred to as “alloy”), and copper and copper. This is a method for separating nickel and cobalt. Specifically, in this separation method, an alloy containing copper, nickel, and cobalt is brought into contact with a sulfuric acid solution containing chloride under the condition that a sulfide agent coexists, and the copper-containing solid, nickel, and cobalt are brought into contact with each other. To obtain a leachate containing.

The processing target of the separation method according to the present embodiment is an alloy containing copper, nickel, and cobalt. As the alloy, for example, waste batteries such as scraps of lithium ion batteries (also referred to as "waste lithium ion batteries") generated during the life of lithium ion batteries or discarded due to deterioration of automobiles and electronic devices are heated. Examples thereof include alloys obtained by melting and reducing, that is, alloys obtained by dry-treating a waste battery. By performing the dry treatment, components such as an organic solvent, aluminum, iron, manganese, phosphorus, fluorine, and carbon can be removed.

Further, an alloy obtained by heating and melting a waste battery and reducing it, for example, cast into a plate shape may be used as a processing target of the separation method of the present embodiment. Further, a powdery substance such as an alloy powder obtained by applying an atomizing method to a molten alloy obtained by heating and melting this waste battery and reducing it may be treated. The atomizing method is a method in which high-pressure gas or water is brought into contact with the molten metal to scatter and quench (solidify) the molten metal to obtain powder. In addition, a rod material that is linearly drawn and appropriately cut may be used as a processing target.

When it is made into a powder, it is preferable that the particle size of the alloy is about 300 μm or less because it is easy to treat. On the other hand, if it is too fine, it is costly and causes dust generation and ignition. Therefore, the particle size of the alloy is preferably about 10 μm or more.

The alloy obtained by dry-treating a lithium-ion battery is a copper alloy having poor solubility and excellent corrosion resistance, and conventionally it was difficult to efficiently and selectively separate copper, nickel, and cobalt. However, according to the separation method according to the present embodiment. , Can be efficiently and selectively separated.

The term "waste battery" as used herein means not only a used battery but also a defective product in the manufacturing process. Further, it suffices that the waste battery is included in the processing target, and it does not exclude the addition of other metals, resins, etc. other than the waste battery as appropriate. In that case, it is a waste battery in the present specification including other metals and resins.

In this embodiment, such an alloy is brought into contact with a chloride-containing sulfuric acid solution under conditions in which a sulfurizing agent coexists. As a result, the copper leached from the alloy can be precipitated as copper sulfide, and a solid containing copper can be obtained. On the other hand, the leached nickel and cobalt remain in the leachate. Thereby, as shown in Examples, copper can be efficiently and selectively separated from nickel and cobalt. Since copper precipitates as a sulfide, it can be made to be almost absent in the leachate, and nickel and cobalt can be present in a very high proportion in the acidic solution (leachate). Therefore, according to the present invention, the selectivity is very high, and copper can be separated from nickel and cobalt.

Further, by using the sulfuric acid solution containing chloride as in the present embodiment, the reaction rate of nickel or cobalt, that is, the leachate of nickel or cobalt is compared with the case of using sulfuric acid containing no chloride. The rate of leaching into can be increased.

The reaction generated by contacting a sulfuric acid solution containing a sulfide agent and chloride with an alloy is shown in the following reaction formula. In the following formula, an example is shown in which solid sulfur (S) is used as the sulfurizing agent and a sulfuric acid solution containing hydrochloric acid is used as the sulfuric acid solution containing chloride. As shown in the following formula (1), by contacting the alloy with a sulfide agent and reacting it, leached copper sulfide is produced. Further, as shown in the following formulas (2) and (3), nickel and cobalt are leached with sulfuric acid of a sulfuric acid solution containing chloride and exist as ions in the leaching solution. Then, the chloride contained in the sulfuric acid solution promotes the leaching of nickel and cobalt. Even when the leached nickel or cobalt reacts with the sulfide agent to generate sulfide, the sulfide of nickel or cobalt is decomposed due to the presence of sulfuric acid, and the nickel or cobalt is present in the leachate. Will be done.
Reaction equation Cu + S → CuS (1)
_{Ni + H 2 SO 4 → NiSO} 4 + H 2 (2)
NiS + H ₂ SO ₄ → NiSO ₄ + H ₂ S (2)'
Co + H ₂ SO ₄ → CoSO ₄ + H ₂ (3)
CoS + H ₂ SO ₄ → CoSO ₄ + H ₂ S (3)'

As the sulfurizing agent, sulfur alone can be used, but liquid or gaseous sulfurizing agents such as sodium hydrogen sulfide (sodium sulfide sulfide), sodium sulfide, and hydrogen sulfide gas may be used.

The chloride-containing sulfuric acid solution used in this embodiment is a solution in which chloride is dissolved in sulfuric acid. As described above, in the present embodiment, a solution in which chloride is dissolved in sulfuric acid is prepared in advance, and the solution is brought into contact with the alloy under the condition of coexistence of a sulfide agent.

As the chloride contained in sulfuric acid, hydrochloric acid, compound salts and the like can be used. When hydrochloric acid is used as the chloride, it is preferable to add hydrochloric acid having a concentration lower than the sulfuric acid concentration to the sulfuric acid solution. Examples of the compound salt include nickel chloride (NiCl ₂ ), cobalt chloride (CoCl ₂ ), sodium chloride, potassium chloride and the like. However, since chloride remains in the leachate, it is preferable to use a compound salt that does not affect the nickel-cobalt separation step in the subsequent step. Specifically, as a compound salt, nickel or cobalt chloride, etc., rather than sodium chloride or potassium chloride, which may be affected when nickel or cobalt is separated in a subsequent step or purified as a product after separation. Is preferably used.

The concentration of chloride added to sulfuric acid (sulfuric acid solution) is sufficient if the amount of Cl is approximately 0.1 g / l or more, and the upper limit is preferably 2 to 3 g / l or less. If the chloride concentration is too high, it is not very effective in promoting leaching, while copper leaching is observed when leaching is continued for a long time, or the resulting solution containing nickel or cobalt (leaching solution) is purified. This is because excessive chloride concentration may increase the load on the refining process and affect the product quality of nickel and cobalt.

Addition of an oxidizing agent such as oxygen, air, or hydrogen peroxide is preferable because leaching is promoted.

The amount of sulfuric acid containing chloride to be brought into contact with the alloy is, for example, 1 equivalent or more of sulfuric acid calculated by the above formulas (2) to (3) with respect to the total amount of nickel and cobalt contained in the alloy. , Preferably 1.2 equivalents or more, more preferably 1.2 equivalents or more and 11 equivalents or less. The reaction rate can be increased by increasing the acid concentration.

Further, the amount of the sulfurizing agent is preferably 1 equivalent or more obtained by the above formula (1) with respect to the amount of copper contained in the alloy.

Slurry concentration obtained by adding a sulfuric acid solution containing chloride and a sulfide agent to the alloy, that is, the ratio of the mass of the alloy to the volume of the slurry (mass of the alloy containing copper, nickel and cobalt / volume of the slurry) Is preferably 20 g / l or more.

The reaction temperature is, for example, 50 ° C. or higher, preferably 75 ° C. or higher, more preferably 95 ° C. or higher, and it is preferable to maintain this during the reaction. Above 95 ° C, the reaction rate can be significantly increased as compared to, for example, below 75 ° C. The reaction time is, for example, 1 to 6 hours.

It is preferable that the sulfuric acid solution containing chloride and the sulfurizing agent are brought into contact with the alloy at the same time, or the sulfuric acid solution containing chloride is brought into contact with the alloy first after the sulfurizing agent is brought into contact with the alloy. When a sulfuric acid solution containing chloride is brought into contact with the alloy in the absence of a sulfide agent, the leaching rate of valuable components is insufficient and iron and the like partially contained in the alloy are not recovered as in the past. Even the components may be leached, which causes an inconvenience that the load in the subsequent purification process increases.

The method of contacting the sulfuric acid solution containing chloride or the sulfurizing agent with the alloy is not particularly limited. For example, the alloy or the sulfurizing agent is added to the sulfuric acid solution containing chloride to mix and stir as necessary. do it. Further, in order to bring the sulfurizing agent into contact with the alloy, a means for containing or applying a solid sulfurizing agent to the alloy in the dry treatment may be used.

According to this embodiment, copper can be separated from nickel and cobalt, but if copper leached from the alloy remains in the leachate and the copper is discharged as it is from the leaching facility or the like, nickel and cobalt can be separated. This is not preferable because the load in the process of separating the copper increases.

Therefore, a copper removal facility for removing copper remaining in the leachate is provided at the outlet of the reaction vessel where the separation method of the present embodiment is performed, and the copper is completely removed and supplied to the nickel-cobalt separation step. It may be. Examples of the method for removing the copper remaining in the leachate include addition of a sulfide agent, electrowinning, and formation of a neutralized starch by the addition of a neutralizing agent.

As described above, according to the method for separating copper, nickel, and cobalt of the present embodiment, copper in an alloy containing copper, nickel, and cobalt is sulfided to form a leachate residue as copper sulfide, which is contained in the leachate. It can be efficiently and selectively separated from residual nickel and cobalt.

The copper sulfide obtained by the method for separating copper, nickel and cobalt of the present embodiment is directly supplied as a raw material for an existing copper smelting process to obtain an anode, and this anode is electrolytically purified to obtain high-purity copper. Can be obtained.

In addition, nickel and cobalt leached into the leachate are supplied to the existing nickel smelting process, and nickel and cobalt are separated by means such as solvent extraction and electrowinned to obtain nickel metal or cobalt metal. It can be purified as a nickel salt or cobalt salt and recycled again as a raw material for lithium-ion batteries.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to the following examples.

(Examples 1 to 12) Sulfate solution containing chloride A molten alloy containing copper, nickel, and cobalt is subjected to a dry treatment in which a waste lithium ion battery (waste LIB) is heated and melted to reduce it. Obtained, poured this into a small rutsubo with a hole in the bottom, and sprayed high-pressure gas or water on the molten metal that flowed out of the hole to scatter, solidify, and sieve the molten metal, and powder with a particle size of 300 μm or less. An alloy powder (hereinafter, for convenience, this alloy powder is also referred to as "atomize powder") was obtained. Table 1 shows the results of analysis of the obtained alloy powder using an ICP analyzer.

Next, 1.0 g of the above alloy powder was collected. Further, 0.35 g of elemental sulfur (solid sulfur), which is one equivalent of forming copper sulfide represented by the above formula (1), was prepared with respect to the copper grade of the alloy powder.

_{Further, NiCl 2} having a Cl amount of 0.006 g, 0.01 g or 0.1 g was separated, respectively.

Further, to the total amount of nickel and cobalt contained in the alloy powder, 2 equivalents of sulfuric acid calculated by the above formulas (2) and (3) and NiCl ₂ fractionated above were added to make a pure solution. diluted to 50ml with water to prepare lysates NiCl ₂ was dissolved (sulfuric acid solution containing NiCl _2).

The temperature of the obtained solution was raised to 95 ° C., 1.0 g of the above alloy powder and 0.35 g of sulfur were added at the same time, and the mixture was stirred for 1 to 6 hours. After stirring for each time, filtration was performed for solid-liquid separation, and the filtrate was analyzed using an ICP analyzer to determine the concentrations of each component of copper, nickel, cobalt, iron, and sulfur. Table 2 shows the leaching conditions and ICP measurement results of each example. In Table 2, the stirring time (reaction time) is referred to as “time” and the temperature rise temperature is referred to as “temperature”. Table 2 also shows the results of measuring the mass of the filtration residue, the amount of liquid after filtration, the pH, and the redox potential ORP (based on the silver / silver chloride electrode). In addition, the leaching rate of each element of copper, nickel, cobalt, and iron was determined. The leaching rate was determined by dividing the mass of the target element in the filtrate by the mass of the target element in the atomized powder. _{However, when determining the nickel leaching rate, the value obtained by subtracting the mass of Ni derived from NiCl 2} added to sulfuric acid from the actually measured mass of Ni in the filtrate is calculated as the above-mentioned "target element in the filtrate". Mass of. " The relationship between the reaction time and the leaching rate of nickel, cobalt, and copper at a leaching temperature of 95 ° C. and _{50 ml of 2 equivalents of sulfuric acid containing NiCl 2 is shown in FIGS.} Further, FIG. 4 shows the relationship between the amount of Cl in the chloride contained in sulfuric acid and the leaching rate of nickel, cobalt, and copper in 50 ml of 2 equivalents of sulfuric acid containing _{NiCl 2} at a leaching temperature of 95 ° C. ..

(Test Examples 1 to 3) The same procedure as in Example was carried out except that _{NiCl 2 sulfate was not used.} The results are shown in Tables 2-3 and FIGS. 1-4.

(Comparative Example 1) Hydrochloric Acid 1.0 g of an alloy powder having a particle size of 300 μm or less obtained in the same manner as in Example was collected. Next, a solution prepared by diluting 3.7 equivalents of hydrochloric acid with respect to the total amount of nickel and cobalt contained in the alloy powder to 15 ml was prepared, and the temperature of this solution was raised to 75 ° C.

Then, 1.0 g of the above alloy powder was added, and the mixture was stirred for 2 hours. Then, filtration was performed to separate the solid and liquid, and the filtrate was analyzed using an ICP analyzer in the same manner as in Examples to determine the concentration of each component. Table 2 shows the leaching conditions and ICP measurement results of Comparative Example 1. Table 2 also shows the results of measuring the amount of liquid after filtration. Table 3 shows the results of determining the leaching rates of each element of copper, nickel, cobalt, and iron in the same manner as in Examples.

(Comparative Example 2) Sulfuric acid 1.1 g of an alloy powder having a particle size of 300 μm or less obtained in the same manner as in Example was collected. Next, 23.8 equivalents of sulfuric acid was fractionated with respect to the total amount of nickel and cobalt contained in the alloy powder, diluted to 50 ml, and the solution was heated to 75 ° C. bottom.

Then, the above alloy powder was added, and the mixture was stirred for 4 hours. At this time, no sulfurizing agent was added. Then, filtration was performed to separate the solid and liquid, and the filtrate was analyzed using an ICP analyzer in the same manner as in Examples to determine the concentration of each component. Table 2 shows the above leaching conditions and ICP measurement results. Table 2 also shows the results of measuring the liquid volume, pH, and ORP after filtration. Table 3 shows the results of determining the leaching rates of each element of copper, nickel, cobalt, and iron in the same manner as in Examples.

(Comparative Example 3)
0.17 g of an alloy powder having a particle size of 300 μm or less obtained in the same manner as in the examples was collected. Next, 70 equivalents of sulfuric acid was fractionated with respect to the total amount of nickel and cobalt contained in the alloy powder, and a solution obtained by diluting this to 20 ml was prepared, and the temperature of this solution was raised to 75 ° C.

Then, the above alloy powder was added, and the mixture was stirred for 4 hours. During that time, Na persulfate was added to the solution being dissolved with 70 equivalents of sulfuric acid until the ORP became 1000 mV or more. Then, filtration was performed to separate the solid and liquid, and the filtrate was analyzed using an ICP analyzer in the same manner as in Examples to determine the concentration of each component. Table 2 shows the above leaching conditions and ICP measurement results. Table 2 also shows the results of measuring the liquid volume and ORP after filtration. Table 3 shows the results of determining the leaching rates of each element of copper, nickel, cobalt, and iron in the same manner as in Examples.

As shown in Tables 2 to 3 and FIGS. 1 to 4, nickel and cobalt could be leached in Examples 1 to 12, which were significantly higher than the copper leaching rate in each Example. From these results, by contacting an alloy containing copper, nickel and cobalt with a sulfuric acid solution containing chloride under the condition that a sulfide agent coexists, copper is precipitated as copper sulfide and nickel is selectively used in the leachate. It was confirmed that copper and nickel and cobalt can be efficiently and selectively separated from the alloy by leaching copper and nickel. Then, it was confirmed that Examples 1 to 12 had a higher reaction rate than Test Examples 1 to 3 using sulfuric acid containing no _{Nickel 2.}

Further, as shown in Tables 2 to 3 and FIGS. 1 to 4, in Examples 1 to 12 in which the mixture was brought into contact with a sulfuric acid solution containing chloride under the condition where a sulfide agent coexisted, the amount of chloride increased. It was confirmed that the reaction was promoted and the reaction rate was increased. Therefore, it was confirmed that by increasing the amount of chloride, the time can be shortened and the selective leaching of Ni and Co is possible.

In Comparative Example 1 in which the sulfide was brought into contact with hydrochloric acid, which is a chloride, without the coexistence of a sulfide agent, as shown in Tables 2 and 3, the leaching rate of copper, nickel, cobalt, and iron was about 50% to 60%. The leaching rate of the valuable component was insufficient, and at the same time, the leaching was uniform, and the separation of the valuable component and the recovery-unnecessary component was also insufficient.

Further, when contacting with hydrochloric acid without coexisting with a sulfide agent, as shown in Tables 2 and 3, copper, nickel, cobalt and iron were around 5% even in Comparative Example 2 in which Na persulfate was not added. The leaching rate was confirmed, and it was confirmed that leaching was performed without selectivity. Further, in Comparative Example 3 in which sodium persulfate, which is not a sulfide agent, was added, it was confirmed that almost all of copper, nickel, cobalt, and iron were dissolved and leached without selectivity.

As described above, in Comparative Examples 1 to 3, it was confirmed that it was difficult to separate copper from nickel and cobalt by leaching without selectivity.

Claims (7)

A separation method for separating copper, nickel and cobalt from an alloy containing copper, nickel and cobalt.
The alloy, depending on Rukoto contacted with sulfuric acid solution to dissolve the chloride under conditions sulfiding agent coexist, the leachate obtained by leaching nickel and cobalt, the solid copper sulfide of copper was sulfided by sulfuric agent And get
Separation method. It said sulfurizing agent is sulfur, hydrogen sulfide gas, separation method according to claim 1 is one or more selected from sodium hydrogen sulfide and sodium sulfide. The chloride-containing sulfuric acid solution and the sulfide agent are brought into contact with the alloy containing copper, nickel, and cobalt at the same time, or the chloride-containing sulfuric acid solution is added after the sulfide agent is brought into contact with the alloy. separation method according to claim 1 or 2 is contacted. The copper, nickel and alloy containing cobalt, heat melting the scrap lithium ion batteries, separation method according to any one of claims 1 to 3 which is reduced to give the alloy. Wherein an alloy powder comprising copper and nickel and cobalt, the particle size of the alloy containing the copper, nickel and cobalt, separation method according to any one of claims 1 to 4 is 300μm or less .. After separation of the leaching solution containing nickel and cobalt and a solid containing the copper, separation method according to any one of claims 1 to 5 to remove copper remaining leaching solution containing the nickel and cobalt .. Sulfide, by one or more method selected from the electrowinning and neutralization precipitation separation method according to claim 6 for removing copper remaining leaching solution containing the nickel and cobalt.

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