JP6786280B2 - Treatment method for ruthenium-containing substances and recovery method for ruthenium - Google Patents

Description

The present invention relates to a method for treating ruthenium-containing substances and a method for recovering ruthenium.

Due to its electrical and electromagnetic properties, ruthenium is used in the electronics industry, especially in thin films for high-capacity hard disks in personal computers, integrated circuits for automotive hybrids, and electrodes for plasma display panels. In addition, since it has high catalytic activity, it is also used in the field of catalytic chemistry such as fuel cells.

Examples of the method for obtaining ruthenium include the following. In the non-ferrous refining process represented by copper refining, a residue containing platinum group elements such as gold and ruthenium, silver and the like is generated as a by-product when recovering copper from a copper-containing raw material. Ruthenium will be recovered from this residue.
Conventionally, the following methods have been known as techniques for concentrating and recovering ruthenium from ruthenium-containing substances.

According to JP-A-2010-215999 (Patent Document 1), a ruthenium-containing material is heated together with an alkali metal hydroxide to a temperature range of 220 to 400 ° C. to obtain a mixture of an alkali melt and a ruthenium-containing solid material. A method for concentrating ruthenium having a "low temperature alkali melting step" is disclosed. By this low-temperature alkali melting step, ruthenium is separated to the solid side, and silicon and aluminum as impurities are separated to the alkaline melt side (Patent Document 1 [0028], etc.).

Japanese Unexamined Patent Publication No. 2009-235513 (Patent Document 2) describes the following contents. First, the ruthenium-containing substance is heated together with an alkali to obtain an alkaline melt, which is cooled to form an alkali melt, and the alkali melt is wet-leached with water to obtain a ruthenium solution. Then, a reducing agent is added to the ruthenium solution until the oxidation-reduction potential is in the range of 50 to 120 mV, impurities are co-precipitated together with ruthenium hydroxide, and impurities are removed by solid-liquid separation. , And a "wet reduction step" in which ruthenium hydroxide is produced by further adding a reducing agent to the ruthenium solution from which the impurities have been removed until the oxidation-reduction potential is in the range of 30 to −300 mV. A method for recovering ruthenium from the ruthenium hydroxide is disclosed (Patent Document 2 [0028] to [0044], etc.).

Japanese Unexamined Patent Publication No. 2010-215999 JP-A-2009-235513

Ruthenium has been increasingly used in the electronics industry in recent years due to its electrical and electromagnetic properties. Therefore, a method for rapidly supplying ruthenium is required. In particular, as a result of diligent research by the present inventors, it has become clear that depending on the impurity elements contained in the ruthenium-containing material, it takes more time and steps than expected. Moreover, it has become clear from the investigation by the present inventors that such a problem can occur even if the methods described in Patent Documents 1 and 2 are adopted.
In this specification, elements other than ruthenium are referred to as impurity elements.

An object of the present invention is to provide a method for rapidly reducing the concentration of impurity elements in a ruthenium-containing substance by a relatively simple process, and thus to provide a method for rapidly recovering ruthenium.

The following contents have been clarified by the diligent research by the present inventors.

The case where a predetermined impurity element (for example, aluminum contained in aluminum oxide and zirconium) is present in the ruthenium-containing material is illustrated. The amount of ruthenium mentioned above has been increasing in recent years in the field of the electronic industry due to its electrical and electromagnetic characteristics. When used in the field of the electronic industry or the like, it is preferable that the ruthenium content is high. When recovering ruthenium, the present inventors reduce the concentration of not only aluminum oxide but also other elements (for example, zirconium) to improve the quality of ruthenium used in the electronic industry. I got the knowledge that it can be improved more than before.

However, in the method described in Patent Document 1, although it is possible to carry out a step for separating aluminum oxide, there is no disclosure about zirconium. Therefore, if it stands on the extension of the conventional technology, it becomes necessary to separately provide a step for separating aluminum oxide and a step for separating zirconium.

Therefore, the present inventors have sought a method for making aluminum oxide and zirconium separable in one step. As a result, we came up with a method of separating aluminum oxide and zirconium into an acid leaching solution by performing acid leaching of the ruthenium-containing substance using a solution containing hydrochloric acid and hydrogen peroxide.

Aspects of the present invention made based on the above findings are as follows.
The first aspect of the present invention is
It is a treatment method for a ruthenium-containing substance, which comprises an acid leaching step of leaching the ruthenium-containing substance with a solution containing hydrochloric acid and hydrogen peroxide.

The second aspect of the present invention is the aspect described in the first aspect.
When the acid leaching step is performed, the conditions are such that the temperature is 50 ° C. or higher and the pH is 1.0 or lower.

A third aspect of the present invention is the aspect described in the first or second aspect.
The hydrogen peroxide concentration in the solution at the start of the acid leaching step is 0.5% by mass or more.

A fourth aspect of the present invention is the aspect described in any one of the first to third aspects.
The ruthenium-containing material contains aluminum and zirconium.

A fifth aspect of the present invention is the aspect described in the fourth aspect.
The ruthenium-containing material contains aluminum oxide.

A sixth aspect of the present invention is
It is a method for recovering ruthenium, which comprises a recovery step for recovering ruthenium from the ruthenium deposit after performing the treatment method for the ruthenium-containing material according to any one of the first to fifth aspects.

According to the present invention, the concentration of impurity elements in the ruthenium-containing material can be quickly reduced by a relatively simple process, and ruthenium can be recovered quickly.

It is a flowchart in this embodiment and Example 1.

Hereinafter, embodiments of the present invention will be described by way of example. However, the present invention is not limited to the following contents.
An embodiment of the present invention (a method for recovering ruthenium) will be described in the following order.
1. 1. Preparation process 2. Acid leaching process (treatment method for ruthenium-containing substances)
3. 3. Recovery process 4. Other processes

<Ruthenium recovery method>
The ruthenium recovery method of the present embodiment mainly has the following steps.
-Acid leaching step in which acid leaching is performed on ruthenium-containing substances using a solution containing hydrochloric acid and hydrogen peroxide.-Recovery of metallic ruthenium (hereinafter, also simply referred to as ruthenium) from ruthenium deposits generated in the acid leaching step. Steps A series of steps shown in FIG. 1 will be specifically described below with a focus on each of the above steps.

1. 1. Preparation step First, the ruthenium-containing material to be treated when recovering ruthenium is prepared.
In the present specification, the ruthenium-containing substance is crushed waste obtained by crushing substrates and electronic parts in waste home appliances and waste electronic devices, or waste materials generated in the manufacturing process of electronic device products, and contains 0.1% by mass of ruthenium. It refers to those contained in a proportion of 50% by mass or less.
It is preferable that the ruthenium-containing material has a fine particle size by crushing or the like before being subjected to the acid leaching step in the present invention. This is because the acid leaching step in the present invention can be efficiently performed because the surface portion in contact with the liquid increases by making the particle size finer.
As a typical example of the ruthenium-containing material in the present embodiment, when ruthenium is vapor-deposited in the electronic industry field or the like, the ruthenium-containing material that is not incorporated into the product but adheres to the adhesive plate of the vapor deposition apparatus is peeled off by blasting. Solid (magnetic film) can be mentioned. In this thin-film deposition process, various metals such as iron, cobalt, chromium, zirconium, platinum and palladium (described later) are continuously used in addition to ruthenium, so that various metals adhere to the adhesive plate. Become. Therefore, the ruthenium-containing material exfoliated by the blast treatment is in a state of containing various metals other than ruthenium. That is, the ruthenium-containing substance is in a state of containing impurity elements other than the ruthenium listed above.
When aluminum oxide powder is used as the blasting material in the blasting treatment, aluminum oxide is mixed with the ruthenium-containing material. When recovering ruthenium, it is necessary to reduce the concentration of impurity elements other than ruthenium as described above.

The form of aluminum contained in the ruthenium-containing material includes aluminum oxide, metallic aluminum (hereinafter, also simply referred to as aluminum), alloys, composite oxides, and the like as cases attached to the protective plate. Although it is conceivable, the concentration can be reduced by the present invention in any form.

However, the ruthenium-containing substances exemplified above are merely examples. When recovering ruthenium, it is not always the case that only those for which all types of elements are known are adopted. On the other hand, even if there is a ruthenium-containing material containing aluminum oxide and zirconium-free ruthenium-containing material, by adopting the method of the present embodiment described in detail later, it is possible to ensure that the ruthenium-containing material is present. The concentration of impurity elements (aluminum, zirconium) in the ruthenium-containing material can be quickly reduced by a relatively simple process.

Incidentally, the ruthenium-containing material may be subjected to a magnetic separation treatment prior to the acid leaching step described later. For example, by using the method described in the patent document of JP2012-179554, ruthenium may be concentrated in a magnetic substance, and then the contents of the present embodiment described below may be applied.

2. Acid leaching process (treatment method for ruthenium-containing substances)
Next, the acid leaching step (that is, the treatment method for the ruthenium-containing substance) in the present embodiment will be described.

The acid leaching treatment in the present embodiment is characterized in that a solution containing hydrochloric acid and hydrogen peroxide is used. By adopting the solution, even if aluminum oxide and zirconium are present in the ruthenium-containing material, a predetermined impurity element (aluminum oxide) can be obtained from the ruthenium-containing material in a relatively simple step called an acid leaching step. Aluminum and zirconium after being melted, as well as platinum and palladium mentioned above) can be leached and separated.

On the other hand, ruthenium has a slight solubility in the solution. Therefore, as shown in Examples described later, some ruthenium is leached from the ruthenium-containing material. However, as will also be shown in Examples described later, both aluminum and zirconium can be leached into the solution and separated by one step. Thanks to this, the time required for the process can be significantly shortened, and the energy cost can be significantly reduced by adopting a relatively simple process of acid leaching. This embodiment is made by paying attention to this merit.

Hereinafter, various suitable conditions for the acid leaching step will be described.

First, regarding hydrochloric acid, the higher the concentration of hydrochloric acid, the faster the leaching reaction rate. However, since hydrogen peroxide is also contained in the solution, the concentration of hydrochloric acid is defined by the concentration of chloride ions in this embodiment. The chloride ion concentration during the acid leaching step in the present embodiment is preferably 5% by mass or more from the viewpoint of increasing the leaching reaction rate.

Next, the concentration of hydrogen peroxide will be described. The hydrogen peroxide concentration at the start of the acid leaching step when preparing an aqueous solution containing hydrochloric acid and hydrogen peroxide is preferably 0.5% by mass or more, more preferably 1.0% by mass or more. It is more preferably 2.0% by mass or more. The start of the acid leaching step is when the ruthenium-containing substance is started to be immersed in a mixed aqueous solution of hydrochloric acid and hydrogen peroxide. Even if hydrogen peroxide is additionally added during this immersion, the start of the acid leaching step is when the ruthenium-containing substance is started to be immersed in the above-mentioned mixed aqueous solution. The concentration of hydrogen peroxide at this time is referred to as "initial concentration of hydrogen peroxide". The higher the initial hydrogen peroxide concentration, the higher the leaching reaction rate, so it is preferable to set the concentration in the above range. Further, the upper limit of the initial hydrogen peroxide concentration is usually set to 10% by mass or less because the effect is leveled off even if the concentration is too high and there is a demerit that the drug cost increases. The hydrogen peroxide concentration correlates with the redox potential, and the higher the hydrogen peroxide concentration, the higher the redox potential tends to be. Therefore, the hydrogen peroxide concentration can be estimated by measuring the redox potential of the liquid. ..
Further, since hydrogen peroxide gradually decomposes in the solution during the acid leaching treatment (hereinafter referred to as acid leaching solution), the initial stage mentioned above is carried out while the acid leaching step, which is the main step, is advanced. It is also possible that the concentration of hydrogen peroxide will be lower than that of hydrogen peroxide. Therefore, it is preferable to add hydrogen peroxide periodically during this step.

Next, the temperature condition in the acid leaching step may be normal temperature, but is preferably 50 ° C. or higher, more preferably 80 ° C. or higher. The higher the acid leaching temperature, the higher the acid leaching reaction rate. Further, the upper limit of the temperature condition is not particularly specified, and may be set to 100 ° C. or lower, which is the boiling point of water.

Next, the pH condition in the acid leaching step is preferably 1.0 or less, more preferably 0.0 or less. The lower the pH of the acid leaching treatment, the higher the reaction rate of acid leaching. The lower limit of the pH condition is not particularly specified, but it may be set to -1.5 or more, which can be adjusted by adding hydrochloric acid.

Next, the time required for the acid leaching step depends on the concentration of impurity elements contained in the ruthenium-containing substance, the chloride ion concentration, the hydrogen peroxide concentration, the temperature, and the pH conditions, but it should be 1 to 5 hours. For example, the concentration of impurity elements can be sufficiently reduced.

The container used in the acid leaching step may be a material that does not invade the container with hydrochloric acid and hydrogen peroxide solution and can withstand the temperature conditions of the acid leaching treatment, such as a hollow pot, a titanium container, and Teflon (registered trademark). ) Container made is suitable.

After performing the above acid leaching step for a predetermined time, the acid leaching solution is cooled by natural cooling. In the acid leachate, an acid leachate containing aluminum or zirconium and a ruthenium deposit are present. Then, ruthenium is recovered from the ruthenium deposit by the following recovery step.

3. 3. Recovery process In this step, ruthenium is recovered from the ruthenium deposits produced by the previous acid leaching step. A known method may be adopted as the recovery method, and it can be appropriately selected depending on the purpose.

To give a specific example, first, a solid-liquid separation step of separating the ruthenium deposits generated by the previous acid leaching step from the acid leaching solution is performed. A known method (filter press, filtration, etc.) may also be used in the solid-liquid separation step.

Then, ruthenium is recovered from the ruthenium deposits separated in the solid-liquid separation step. As an example of the recovery method, there is a method of recovering ruthenium by adopting the method of alkali melting described in JP-A-2009-57611 (also described in Examples described later). With this method, ruthenium can be recovered in a high yield, so it is preferable to carry out the alkali melting step described in the publication. Then, after the alkali melting step, a water leaching step and a solid-liquid separation step are performed again to obtain a ruthenium solution, which is a filtrate, and metallic ruthenium is obtained from the ruthenium solution by a known method.

Here, in the present embodiment, the concentration of aluminum has already been remarkably reduced thanks to the previous acid leaching step. Therefore, there is also an effect that the foaming phenomenon of the alkaline solution in the alkali melting step, which is mentioned as a problem in Patent Document 1, does not occur.

Through each of the above steps, ruthenium is recovered from the ruthenium monument. Then, in the present embodiment, the concentration of the impurity element in the ruthenium-containing material can be quickly reduced by a relatively simple process, and ruthenium can be recovered quickly.

4. Other Steps As described above, the method of recovering ruthenium from the ruthenium deposits after reducing the concentration of impurity elements in the ruthenium-containing material has been described. On the other hand, the ruthenium-containing material may contain a noble metal, platinum or palladium, as an impurity element other than ruthenium. In that case, thanks to the acid leaching step described above, most of the platinum or palladium is acid leached and transferred to the acid leaching solution side. Then, platinum or palladium, which is a noble metal, can be recovered from the filtrate separated from the ruthenium deposit by the solid-liquid separation step by a known method such as salting out or adsorption to an ion exchange resin. In other words, the above acid leaching step (that is, the treatment method for ruthenium-containing substances) is a simple method of not only separating aluminum and zirconium, which are impurity elements, but also acid leaching of platinum and palladium, which are precious metals. It also has the effect of concentrating platinum and palladium into an acid leachate and thus improving the quality of platinum and palladium obtained from the acid leachate.

In summary, among the impurity elements listed above, for example, platinum and palladium can be separated by migrating to an acid leachate like aluminum and zirconium.

Hereinafter, examples of the treatment method for the ruthenium-containing material according to the present invention will be described in detail. In the following example, the actual recovery of ruthenium has not been carried out, but by measuring the content of ruthenium in the ruthenium solution at the stage immediately before the actual recovery of ruthenium, the ruthenium is actually recovered. We are verifying the effect on the assumption that it will be collected.
Before the detailed explanation, the equipment and conditions used for each measurement will be briefly explained.

The contents of ruthenium and platinum described in the present specification are measured using an inductively coupled plasma emission spectroscopic analyzer (manufactured by SII, product name SPS5100), and the contents of other elements are measured by a fluorescent X-ray analyzer (manufactured by SII). It was measured using a product name XRF-1700) manufactured by SHIMADZU.

The pH value described in the present specification was measured using a glass electrode based on JIS Z8802, and was measured by a pH meter calibrated with an appropriate buffer solution according to the pH range to be measured. The value. Further, the pH described in the present specification is a value obtained by directly reading the measured value indicated by the pH meter compensated by the temperature compensating electrode under the temperature condition of acid leaching.

Further, the value of the redox potential described in the present specification is a standard redox potential measured by the platinum electrode.

[Example 1]
1. 1. Preparation Step The surface of the base material to which ruthenium and platinum were attached was blasted with alumina (aluminum oxide) powder to obtain a blasted product. A magnetic deposit (starting material) was obtained by performing a wet magnetic separation treatment on this blasted product. As a result of measuring the content of each element in the starting material by the above apparatus, ruthenium (Ru) 15.0% by mass, platinum (Pt) 6.0% by mass, aluminum (Al) 4.0% by mass, zirconium (Zr) was 0.150% by mass. The Al / Ru ratio was 0.267, and the Zr / Ru ratio was 0.01000.

2. Acid leaching process (treatment method for ruthenium-containing substances)
30 L of water, 30 L of hydrochloric acid having a concentration of 35% by mass, and 5 L of hydrogen peroxide solution having a concentration of 35% by mass were placed in a titanium container having a capacity of 120 L and mixed. The hydrogen peroxide concentration of this mixed solution was 2.8% by mass, and the redox potential was 500 mV. After adding 8.5 kg of the starting material to this mixed solution to prepare a mixed slurry, the liquid temperature of this mixed slurry was adjusted to 90 ° C. Then, a hydrogen peroxide solution having a concentration of 35% by mass was added at a rate of 60 cm ³ / min for 6 hours. The pH of the mixed slurry at the start of the addition of the hydrogen peroxide solution was −0.7, and the pH was maintained at 0 or less during the addition of the hydrogen peroxide solution. Further, the redox potential of the mixed slurry is increased by continuing the addition of the hydrogen peroxide solution, and reaches 800 mV 2 hours after the start of the addition of the hydrogen peroxide solution, and then 800 mV until the addition of the hydrogen peroxide solution is completed. It was changing at a value of ~ 850 mV. The liquid was stirred with a stirrer from the preparation of water or the like into the titanium container to the completion of the addition of the hydrogen peroxide solution.

3. 3. Recovery process (solid-liquid separation process)
After the addition of the hydrogen peroxide solution was completed, solid-liquid separation was carried out with a filter press to obtain a solid content of ruthenium and an acid leachate. The obtained ruthenium product was dried for 8 hours to obtain 5.0 kg of a dried product of ruthenium (hereinafter, simply referred to as a dried product).

(Alkaline melting process)
To 5.0 kg of the dried product, potassium hydroxide, which is 5 times the mass ratio of the dried product as an alkali, and potassium nitrate, which is 0.6 times the mass ratio of the dried product, are added as an oxidizing agent. It was sealed in a pot and heated in a fixed furnace. The crucible used was made of silver. The temperature of the fixed furnace was set to 500 ° C. and maintained for 13 hours. There was no foaming phenomenon of the alkaline melt during the temperature rise and retention. After that, it was naturally allowed to cool in the furnace.

The crucible is cooled to room temperature to form an alkaline melt mass, and water is added to the crucible to leach the solid remaining in the crucible, and then solid-liquid separation is performed to separate the ruthenium solution, which is a filtrate, and the solid content. Obtained with some residue.

<Calculation of distribution rate>
In this example, the distribution ratio of each element was calculated for the starting material, the magnetic deposit, the dried product, the acid leachate, the residue after the alkali melting step, and the ruthenium solution after the alkali melting step. The table below summarizes the results.

Here, a method of calculating the distribution ratio of each element will be described. The distribution ratio is calculated as a relative value with respect to the total mass of the starting material by calculating the mass of each element contained in the obtained dried product, with the total mass of the starting material as 100%. By using this index of distribution rate, it is possible to compare how each element in the starting material was distributed in each step on the same basis.

Hereinafter, the process of calculating the distribution ratio of each element will be described with reference to ruthenium as an element, as a starting material, and a dried product of ruthenium.
First, the weight of the input starting material was 8.5 kg, and the ruthenium content in the starting material was 15% by mass. The weight of the obtained dried product was 5.0 kg, and the ruthenium content in the dried product was 21.4% by mass. Therefore, the ruthenium distribution rate in the dried products is
15% * (5.0 * 0.214) / (8.5 * 0.15) = 12.6%
Is calculated.

By the above method, the distribution ratio was calculated in the same manner for each element in the dried product. As a result, it was calculated that ruthenium was 12.6%, platinum was 0.3%, aluminum was 0.4%, zirconium was 0.060%, the Al / Ru ratio was 0.032, and the Zr / Ru ratio was 0.00476.
In addition, when the distribution ratio in the acid leachate was calculated from the difference in the distribution ratio between the starting product and the dried product, ruthenium was 2.4%, platinum was 5.7%, aluminum was 3.6%, and zirconium was 0.090. %, The Al / Ru ratio was calculated to be 1.500, and the Zr / Ru ratio was calculated to be 0.03750.

Then, the distribution ratio of each element was calculated for the residue after the alkali melting step and the ruthenium solution after the alkali melting step. As a result, the distribution ratio in the residue was calculated to be 1.0% ruthenium, 0.3% platinum, 0.055% zirconium, and the Zr / Ru ratio was 0.05500.
The distribution ratio in the ruthenium solution after the alkaline melting step was calculated from the difference between the dried product and the residue. As a result, ruthenium was calculated to be 11.6%, platinum to be 0.0%, zirconium to be 0.005%, and the Zr / Ru ratio to be 0.00043.
The concentration of aluminum was not measured because it could be confirmed that the concentration was already low enough to prevent foaming in the alkali melting step.

Here, the zirconium / ruthenium ratio in the ruthenium solution 1 was a very low result of 0.00043, and it was found that the concentration of zirconium in the ruthenium recovered product could be reduced.

4. Other processes (platinum recovery process)
In this example, the platinum recovery step was actually performed. Since platinum, which is a valuable metal, is dissolved in the acid leaching solution obtained in the acid leaching step in the form of platinum-chlorine complex {PtCl ₆ } ^2- , potassium ions are added to this acid leaching solution to add potassium chloride K ₂ Platinum was recovered using a salting reaction for precipitating PtCl ₆ .

To the acid leachate, potassium chloride powder having a molar ratio of 2.5 times the amount of platinum in the acid leachate was added and stirred for 30 minutes. The slurry obtained after stirring was separated into solid and liquid, and then the solid content was dried to obtain a platinum recovered product. The platinum content in the platinum recovered product was 36.3% by mass.

[Comparative Example 1]
In this comparative example, aluminum as an impurity element was separated by low-temperature alkaline melting.

The same starting material as in the examples, sodium hydroxide having a molar ratio of 2.5 times the amount of aluminum in the starting material, and hydroxide having a molar ratio of 2.5 times the amount of aluminum in the starting material. Potassium hydroxide was sealed in a stainless steel container and placed in a constant temperature heater. By fixing the set temperature of the constant temperature heater to 250 ° C. and holding it for 2 hours, low-temperature alkali melting was performed to obtain a mixture of the alkali melt and the alkali melt residue. Then, the mixture was allowed to cool naturally in a heater.

The container of the above mixture was cooled to room temperature to solidify, and water was added thereto to leach the solid remaining in the container. The obtained slurry after water leaching was suction-filtered with a glass filter to obtain an alkali melt residue as a solid content and a water leaching solution as a filtrate.

After this solid-liquid separation, the alkali melt residue was dried to obtain a dried product having a reduced aluminum concentration. The results of the distribution ratio of each element in Comparative Example 1 are shown in the table below.
The distribution ratio in the alkaline melt residue of Comparative Example 1 was ruthenium 15%, platinum 6%, aluminum 0.1%, zirconium 0.15%, Al / Ru ratio 0.007, and Zr / Ru ratio 0.01. Was calculated.
Moreover, when the distribution ratio in the water leachate was calculated, it was calculated as ruthenium 0%, platinum 0%, aluminum 3.9%, and zirconium 0%.

In Comparative Example 1, it was possible to reduce the concentration of aluminum in the ruthenium-containing material, which is the starting material, by using the method of low-temperature alkali melting. However, it was not possible to reduce the concentration of zirconium, another impurity element. In the first place, the starting material of this example also contained zirconium and platinum, which is a precious metal, but this platinum could not be separated either.

[Summary]
As a result of the above, according to this example, it was found that the concentration of impurity elements in the ruthenium-containing material can be rapidly reduced by a relatively simple process, and that ruthenium can be recovered quickly.

Claims (5)

It has an acid leaching step in which acid leaching is performed on ruthenium-containing substances using a solution containing hydrochloric acid and hydrogen peroxide.
A method for treating a ruthenium-containing material, wherein the ruthenium-containing material contains aluminum and zirconium. The method for treating a ruthenium-containing substance according to claim 1 , wherein the hydrogen peroxide concentration in the solution at the start of the acid leaching step is 0.5% by mass or more. The method for treating a ruthenium-containing material according to claim 1 or 2 , wherein the ruthenium-containing material contains aluminum oxide. The method for treating a ruthenium-containing substance according to any one of claims 1 to 3, wherein the acid leaching step is performed under the conditions of a temperature of 50 ° C. or higher and a pH of 1.0 or lower. A method for recovering ruthenium, which comprises a recovery step for recovering ruthenium from the ruthenium deposit after performing the treatment method for the ruthenium-containing material according to any one of claims 1 to 4 .