JP7036229B2 - Manganese recovery method and recovery equipment from waste batteries - Google Patents

Description

The present invention relates to a method and equipment for recovering valuable metals from waste dry batteries. In the present invention, manganese, which is a major valuable component of discarded manganese dry batteries and / or alkaline manganese dry batteries, can be separated as a valuable metal and recovered as high-purity manganese that can be used for various batteries. Manganese recovery method and recovery equipment.

In recent years, due to the depletion of metal resources and rising transaction prices, it has become necessary to actively recover valuable metals from low-grade ore, concentrates, ironworks by-products, industrial waste, etc. .. For example, manganese, which is one of the valuable metals, is regarded as an essential metal in various fields of industry, and there is concern that its demand will exceed its reserves in the future. In particular, steelworks have traditionally consumed a large amount of manganese as a raw material for steelmaking, and securing a manganese source has become an extremely important issue in the steelmaking field. In recent years, the consumption of manganese for secondary batteries such as lithium-ion batteries has been increasing, and securing a manganese source has become an extremely serious problem in this secondary battery field as well.

On the other hand, in Japan, a huge amount of dry batteries are produced, consumed, and disposed of as industrial waste. Some of the dry batteries (waste dry batteries) that are discarded as industrial waste have a high manganese content. For example, a manganese dry battery and an alkaline manganese dry battery, which are typical as primary batteries, use manganese dioxide as a positive electrode material and zinc as a negative electrode material. In manganese dry batteries, zinc chloride may be used as the electrolytic solution. Further, iron is used for the outer cylinder portion of these waste dry batteries.

Therefore, there is a demand for a technique for recovering a manganese component from these waste dry batteries and reusing it as a raw material for steelmaking. From this point of view, various techniques for recovering not only zinc, iron and carbon but also manganese from waste batteries have recently been proposed.

For example, in Patent Document 1, manganese batteries and alkaline manganese batteries are selected from waste dry batteries, crushed and screened to obtain powders and granules, and the obtained powders and granules are subjected to acid treatment by dissolving them with dilute hydrochloric acid or dilute sulfuric acid. A method for recovering a metallurgical raw material from a waste dry battery has been proposed in which manganese dioxide and a carbon-containing mixture are separated and recovered. The manganese dioxide and carbon-containing mixture recovered by the technique described in Patent Document 1 can be used as a starting material for ferromanganese production or as a material directly used in a smelting furnace in place of ferromanganese.

Further, Patent Document 2 proposes a technique for separating and recovering manganese dioxide and zinc chloride from a waste dry cell. The technique described in Patent Document 2 is to obtain a material containing a large amount of manganese and zinc from a waste dry cell, wash the material with water, dissolve it in hydrochloric acid, remove insoluble matter (carbon powder, etc.), and perform chloride. After making a mixed aqueous solution of manganese and zinc chloride and removing impurities by purifying the solution, heat and concentrate it, add perchloric acid to the concentrate and heat it to oxidize manganese chloride in the solution to manganese dioxide. After obtaining a solid mixture of manganese dioxide and zinc chloride, water is added to the obtained solid mixture to dissolve zinc chloride, and the mixture is filtered to separate and recover insoluble manganese dioxide and water-soluble zinc chloride. , Technology. In the technique described in Patent Document 2, the zinc chloride solution is dissolved in an organic solvent to obtain a purified product of zinc chloride. The point of the technique described in Patent Document 2 is to convert manganese chloride into manganese dioxide with a small amount of perchloric acid, and the manganese dioxide and zinc chloride obtained by the technique described in Patent Document 2 are new manganese. It is said that it can be used in the manufacture of dry batteries.

Further, in Patent Documents 3 to 5, manganese is described by allowing an acid or an acid and a reducing agent to act on manganese-containing powders obtained by crushing and sieving a waste dry battery, and further allowing ozone to act on the obtained manganese solution. A technique for recovering manganese, which is a valuable component, from a waste dry cell by precipitating only as an oxide is described.

More specifically, Patent Document 3 proposes a method for recovering valuable components from waste batteries. In the technique described in Patent Document 3, a step of selecting a manganese dry battery and / or an alkaline manganese dry battery from a waste dry battery, and a crushing / sieving step of crushing and sieving the dry battery selected in the sorting step to obtain powders and granules. And the acid leaching step of mixing the powder and granules obtained in the crushing and sieving step with the acid solution and the reducing agent to leached manganese and zinc from the powder and granules, and the leachate obtained in the acid leaching step. Ozone is allowed to act on the leachate separated in the first solid-liquid separation step of solid-liquid separation and the first solid-liquid separation step to oxidize and precipitate the manganese ions contained in the leachate. The ozone treatment step of obtaining the manganese-containing precipitate and the zinc ion-containing solution and the second solid-liquid separation step of solid-liquid separating the manganese-containing precipitate obtained in the ozone treatment step and the zinc ion-containing solution are sequentially performed. , The manganese component contained in the waste dry battery is recovered as a manganese-containing precipitate. As a result, according to the technique described in Patent Document 3, it is possible to extract high-purity manganese from a waste dry cell with extremely little contamination of zinc, carbon and the like. In Patent Document 3, an alkaline agent is added to the zinc ion-containing solution to perform an alkaline precipitation treatment step in which zinc ions in the zinc ion-containing solution are used as a zinc-containing precipitate, and the zinc component contained in the waste dry battery is subjected to an alkaline precipitation treatment step. Is being collected.

Further, Patent Document 4 proposes a method for separating resources from waste batteries. In the technique described in Patent Document 4, a step of selecting a manganese dry battery and / or an alkaline manganese dry battery from a waste dry battery, and a crushing / sieving step of crushing and sieving the selected dry battery in the sorting step to obtain powders and granules. An acid leaching step of subjecting the powder and granules to an acid leaching treatment using an acid solution to obtain a leaching solution containing manganese and zinc and a leaching residue containing manganese, and a leaching solution and a leaching residue obtained in the acid leaching step. Ozone is allowed to act on the leachate separated in the first solid-liquid separation step and the first solid-liquid separation step to oxidize and precipitate the manganese ions contained in the leachate, resulting in manganese-containing precipitation. A waste dry battery is sequentially subjected to an ozone treatment step for obtaining a product and a zinc ion-containing solution and a second solid-liquid separation step for solid-liquid separation between the manganese-containing precipitate obtained in the ozone treatment step and the zinc ion-containing solution. The manganese component contained in the waste dry cell is separated as a leachate residue and a manganese-containing precipitate, and the zinc component contained in the waste dry battery is separated as a zinc ion-containing solution.

Further, Patent Document 5 describes a method for producing high-grade metallic manganese. In the technique described in Patent Document 5, a manganese-containing substance and a reducing agent and a flux are charged into an arc melting furnace, and the manganese-containing substance is reduced by energization and / or the reaction heat of the reducing agent to reduce the metal. This is a method for producing high-grade metallic manganese, which is manganese. In the technique described in Patent Document 5, manganese contained in a waste dry cell is subjected to acid leaching treatment as a manganese-containing substance, the obtained acid leaching solution is subjected to ozone treatment, and only manganese is precipitated as an oxide and then separated. The manganese-containing substance obtained by the treatment is used.

Further, in Patent Documents 6 to 7, manganese is recovered by leaching manganese from a metal oxide or a metal hydroxide by using ferric iron obtained by reacting ferric iron with iron-reducing bacteria. The technology to be used is described.

More specifically, Patent Document 6 proposes a metal recovery method. In the technique described in Patent Document 6, iron-reducing bacteria are allowed to act on a group consisting of a metal oxide and a metal hydroxide to reduce trivalent iron to divalent iron, and the obtained divalent iron is used. , Metals such as cobalt, nickel, and manganese contained in the group consisting of metal oxides and metal hydroxides are leached to generate a leachate and a residue, and the obtained leachate and the residue are separated to recover the desired metal. How to do it. According to this technology, low-grade metals contained in metal oxides and metal hydroxides can be recovered at high speed and with high efficiency.

Further, Patent Document 7 proposes a manganese recovery method. In the technique described in Patent Document 7, a treatment liquid containing ferric iron ion is mixed with a manganese-containing object to be treated and iron-reducing bacteria, and trivalent iron ion is reduced to ferric iron ion. A leaching step of leaching manganese ions from the object to be treated using iron ion as a reducing agent, a solid-liquid separation step of solid-liquid separating the obtained leachate, and manganese contained in the separation liquid after the solid-liquid separation step. It is a technique having an insolubilization step of oxidizing ions to insolubilize, and a step of precipitating and separating and recovering the obtained manganese component. As a result, manganese can be concentrated and recovered at a high concentration rate under relatively mild conditions, and manganese can be recovered inexpensively and easily from a large amount of object to be treated.

Japanese Unexamined Patent Publication No. 2007-012527 Japanese Unexamined Patent Publication No. 11-191439 International Publication No. 2015/162902 Japanese Unexamined Patent Publication No. 2015-206777 Japanese Unexamined Patent Publication No. 2016-156074 Japanese Unexamined Patent Publication No. 2007-113116 Japanese Unexamined Patent Publication No. 2014-5496

However, at present, for the recovery of valuable metals from waste batteries such as discarded manganese dry batteries and alkaline manganese dry batteries, the zinc refining maker recovers a part of zinc contained in the waste dry battery, or a part of the electric furnace. Manufacturers are only recovering some of the iron and carbon contained in waste batteries. Then, most of the valuable metals contained in the waste dry batteries are not recovered and are sent to landfill processing as waste materials. This is due to the fact that it is technically difficult to separate various valuable metals contained in waste dry batteries, and that there remains a problem in economic efficiency.

In this regard, Patent Document 2 describes that the recovered manganese can be used for manufacturing a new manganese dry battery. However, the technique described in Patent Document 2 has a problem that the procedure is complicated, and also has a problem that the manufacturing cost rises because it includes a process that consumes a large amount of energy such as heating and concentrating.
Further, all of the manganese recovered from the waste dry batteries by the techniques described in the above-mentioned patent documents other than Patent Document 2 have a problem of low purity as a raw material for an electrode material of a secondary battery.

When the recovered manganese is used as a raw material for an electrode material of a secondary battery, its purity is required to be high. This is because impurities mixed in the electrode material of the secondary battery have a significant effect on the performance of the secondary battery such as discharge capacity and repeatability, and cause a significant deterioration in the performance of the secondary battery. .. Furthermore, in recent years, it has become clear that the presence of impurities mixed in the electrode material of a secondary battery may cause ignition of the battery due to a short circuit. Therefore, manganese used as a raw material for an electrode material of a secondary battery is required to strictly reduce impurities.

However, with the above-mentioned conventional technique, it is extremely difficult to recover the manganese component from the waste dry cell easily and at low cost with high purity. Therefore, in the prior art, manganese in waste batteries has not been effectively recycled.

The present invention has been made in view of the above-mentioned problems of the prior art, and manganese contained in a waste dry cell can be recovered as a high-purity manganese-containing solution containing extremely little contamination of impurities such as zinc, iron, and carbon. , Aim to provide a method and equipment for recovering manganese from waste batteries.
The term "high-purity manganese-containing solution" as used herein refers to an analytical method in which zinc (Zn), iron (Fe), carbon (C), etc. are contained as impurities in the solution and are defined in the commonly used JIS standard. A manganese-containing solution that is less than the analysis limit, for example, less than 0.1 mg / L in the analysis using.

When a manganese dry cell and / or an alkaline manganese dry cell is selected from the waste dry cell, and these are crushed and sieved, the material constituting the dry cell is separated into a solid substance on the sieve and a powder or granule under the sieve. Among the materials constituting the dry battery, mainly iron-skin-like packaging materials, zinc cans, brass rods, paper materials, plastics and the like become foil-like or piece-like solids after crushing and are separated on a sieve. On the other hand, manganese dioxide, carbon, zinc chloride, ammon chloride, caustic potash, or MnO (OH), Zn (OH) ₂ , Mn (OH) ₂ , ZnO, etc. generated by discharge become powders and granules, and are sieved. Is separated into. Normally, a small amount of iron is inevitably mixed in the powder or granular material.

In order to achieve the above-mentioned object, the present inventors have diligently studied an impurity separation means effective for recovering manganese contained in a waste dry cell as a high-purity manganese-containing solution having few impurities. In particular, the present inventors have selected one or both of manganese dry batteries and alkaline manganese dry batteries from waste dry batteries, and further crushed and sieved the powders and granules obtained by allowing an acid and a reducing agent to act on the powders and granules. After obtaining a leachate in which manganese, zinc, and iron were leached out, how to remove unintended components (impurities) from the leachate was enthusiastically studied.
As a result, if the zinc component and the iron component are selectively precipitated and separated from the obtained leachate according to a predetermined procedure, the present inventors have a high degree of impurities, regardless of the order of the precipitation and separation steps. It was found that a pure manganese solution can be obtained.

As a more specific embodiment, the present inventors first act on the obtained leachate to form a zinc-containing precipitate when the zinc component is removed prior to the iron component. I came up with the idea of performing a precipitation treatment step and a zinc separation step of separating the obtained zinc-containing precipitate (procedure A). The present inventors selectively precipitate zinc ions contained in the leachate as sulfide (zinc precipitate precipitate) by allowing a sulfide such as sodium hydrosulfide NaHS to act on the leachate, and then from the leachate. It was found that the zinc ion concentration in the solution (first solution) left after the separation of the zinc component can be reduced to less than the analysis limit (0.1 mg / L) while preferentially separating the zinc component. In addition, the present inventors have also found that the zinc component can be better separated from the leachate by adjusting the amount of sulfide to act on, the concentration of sulfide ions, and the pH of the leachate.
Then, the first solution after separating the zinc component is subsequently subjected to an oxidation treatment to make iron ions into an iron-containing precipitate, and if the obtained iron-containing precipitate is further separated, it remains after the separation of the iron component. It was found that a high-purity manganese solution with few impurities can be obtained as the solution (second solution).

Further, as a specific other embodiment, when the iron component is removed prior to the zinc component, the present inventors perform an oxidation treatment step of subjecting the obtained leachate to an oxidation treatment to form an iron-containing precipitate. I came up with the idea of performing an iron separation step to separate the obtained iron-containing precipitate (procedure B). The present inventors selectively precipitate iron ions contained in the leachate, for example, as hydroxides by oxidizing the leachate with air, for example, while preferentially separating only the iron component from the leachate. , It was found that the iron ion concentration in the solution (first solution) left after the separation of the iron component can be reduced to less than the analysis limit (0.1 mg / L). In addition, the present inventors have also found that by adjusting the pH of the leachate, only the iron component can be better separated from the leachate.
Then, the first solution after separating the iron component is subsequently subjected to a sulfide precipitation treatment in which a sulfide such as sodium hydrosulfide NaHS acts, and the zinc ion is further separated as a zinc-containing precipitate to further separate the zinc component. It was found that it is effective to efficiently obtain a high-purity manganese-containing solution with less contamination of impurities as the solution (second solution) left after the separation.

First, the experiments (A) and (B) according to the above procedures (A) and (B), which are the basis of the present invention, will be described.

Experiment (A)
From the waste batteries, manganese dry batteries and alkaline manganese dry batteries were sorted (sorting step), the obtained waste dry batteries were crushed, and sieved with a sieve having a mesh size of 2.8 mm to obtain powder particles of the waste dry batteries (separation step). Crushing / sieving process).
The obtained powder or granular material was mixed with an acid solution and hydrogen peroxide H ₂ O ₂ as a reducing agent, and subjected to an acid leaching treatment for leaching manganese, zinc and iron from the powder or granular material (acid leaching step). .. The acid concentration of the acid solution in the acid leaching treatment is sulfuric acid concentration: 2N (mass% concentration: about 9.0%), the addition amount of hydrogen peroxide H ₂ O ₂ is 45 g / L, and the acid leaching treatment time is 1 hour. The stirring process was carried out. By this acid leaching step, a mixture of a leachate containing at least manganese ion, zinc ion and iron ion and other leaching residue was obtained.
After the acid leaching treatment, the obtained mixture was suction-filtered with a filter paper having a pore size of 1 μm, and the leachate and the leachate residue were separated into solid and liquid (solid-liquid separation step). When the manganese concentration, zinc concentration, and iron concentration in the separated leachate were measured by ICP emission spectrometry, the manganese concentration was 30,000 mg / L, the zinc concentration was 16500 mg / L, and the iron concentration was 380 mg / L.

Then, the obtained leachate was subjected to a sulfide precipitation treatment step in which sodium hydrosulfide NaHS as a sulfide was added under various conditions. Sodium hydrosulfide NaHS was dissolved in distilled water and added in the form of a solution.
The conditions for the sulfide precipitation treatment were as follows.
Leachate: 100 mL
Sulfide type: Sodium hydrosulfide (NaHS)
Addition amount of sulfide: 1 to 3 equivalents of sulfur with respect to dissolved zinc pH of leachate during reaction: 0.5 to 5
Acidity regulator: 3M sulfuric acid or 100g / L sodium hydroxide Treatment time: 0.5 hours after addition of sodium hydrosulfide (stirring treatment)
Then, after the sulfide precipitation treatment, suction filtration is performed with a filter paper having a pore size of 1 μm to perform solid-liquid separation (zinc separation step), and the components (zinc, iron, manganese) of the separated first solution are quantified by the ICP emission analysis method. analyzed. The analytical values obtained were corrected for the effect of being diluted by the addition of the sodium hydrosulfide solution and the pH adjuster. Of the obtained results, zinc and iron are shown in FIG. FIG. 4 does not show the analysis result of manganese.

From FIG. 4A, when the amount of sulfide added is 1 equivalent (NaHS: 1 equivalent), although the zinc precipitate is removed, it exceeds the analysis limit (0.1 mg / L) and is incomplete. Moreover, it can be seen that the final removal rate when the pH is increased is not stable.
On the other hand, as shown in FIG. 4B, when the amount of sulfide added is 2 equivalents (NaHS: 2 equivalents), the removal of zinc precipitate is remarkable. In particular, under the condition that the pH of the leachate is 3 or more, it is removed until the zinc concentration in the first solution after the zinc removal step (sulfide precipitation treatment step and zinc separation step) becomes less than the analysis limit (0.1 mg / L). You can see that it has been done. Further, even when the amount of sulfide added shown in FIG. 4 (c) is 3 equivalents (NaHS: 3 equivalents), the same tendency as in the case of 2 equivalents is shown, and in particular, the zinc concentration when the pH is 3 or more. Is below the analysis limit (0.1 mg / L), and the removal of zinc precipitates is remarkable.

From FIG. 4, it can be seen that the zinc precipitation step also removes the iron precipitate. As shown in FIG. 4 (b), when the amount of sulfide added is 2 equivalents (NaHS: 2 equivalents), iron is precipitated and removed under the condition that the pH is 3 or more, and when the pH is about 5, iron is precipitated and removed. It can be seen that the Fe concentration is reduced to about 1 mg / L. Under this condition shown in FIG. 4 (b), the manganese concentration also began to decrease to about 24000 mg / L, although not shown. That is, it can be seen that under the condition that the amount of sulfide added is 2 equivalents and the pH is 3 or more, manganese is partially precipitated and removed at the same time as zinc and iron.
Further, it can be seen that even when the amount of sulfide added shown in FIG. 4C is 3 equivalents (NaHS: 3 equivalents), iron is precipitated and removed with the same tendency as in the case of 2 equivalents. As shown in FIG. 4 (c), it can be seen that the iron precipitate removal is particularly remarkable when the pH is 5, and the iron is removed until it becomes less than 0.1 mg / L (to the same extent as the zinc concentration). However, although not shown, when the pH was 5 in FIG. 4 (c), the manganese concentration was significantly reduced, and 30% or more of manganese was precipitated and removed. That is, under the condition that the amount of sulfide added is 3 equivalents and the pH exceeds 3, in addition to the removal of zinc, iron and manganese may be precipitated in a larger amount than when the amount of sulfide added is 2 equivalents. Recognize.

As described above for Experiment (A), according to the zinc removal step using a leachate containing manganese ion, zinc ion and iron ion, the zinc component can be precipitated and separated and removed to a level below the analysis limit. In addition, iron (Fe) may be partially precipitated together with zinc (Zn). If the iron (Fe) concentration has been precipitated and removed to some extent, it is conceivable that the treatment will be completed at this stage. However, in order to remove iron to a higher degree, the present inventors have an iron removal step of precipitating iron ions contained in the first solution separated after the zinc removal step as an iron-containing precipitate such as hydroxide (). I came up with the need to further perform an oxidation treatment step and an iron separation step).

Experiment (B)
According to the same method as in Experiment (A), the manganese concentration, zinc concentration, and iron concentration in the leachate separated by the solid-liquid separation step were measured by ICP emission spectrometry. The manganese concentration was 30,000 mg / L, and the zinc concentration was 16650 mg. / L, iron concentration was 380 mg / L.

Then, the obtained leachate was subjected to air aeration as an oxidation treatment (oxidation treatment step). The conditions for air aeration were as follows.
Blow-in amount: (same volume as leachate volume) / min Aeration time: 30 minutes pH of leachate during reaction: 4-6
pH adjuster: 3M sulfuric acid or 100g / L sodium hydroxide Then, the entire amount of leachate after air aeration is suction-filtered with a filter paper having a pore size of 1 μm and solid-liquid separated (iron separation step), and the components of the separated first solution are separated. Concentrations (zinc, iron, manganese) were measured by ICP emission analysis. The obtained measured values were corrected for the effect of dilution by the pH adjuster. The obtained results are shown in FIG. Since precipitation of manganese and zinc by the oxidation treatment step was hardly confirmed, FIG. 5 shows only the iron concentration in the first solution after the iron removal step (oxidation treatment step and iron separation step).

From FIG. 5, when the leachate has a pH of 5 or 6, iron precipitation removal proceeds remarkably, and the iron concentration in the first solution after the iron removal step becomes less than the analysis limit (0.1 mg / L). ing. From this, it was found that the iron concentration can be reduced to less than the analysis limit (0.1 mg / L) simply by applying air aeration, which is an inexpensive oxidation treatment, to the leachate. Although not shown, zinc tended to precipitate slightly when the pH of the leachate was 6. However, the amount was as small as about 5% of the total Zn amount.

In this way, the leachate adjusted to pH: 5 is subjected to air aeration (oxidation treatment) to bring the iron concentration after the oxidation treatment step to less than the analysis limit (0.1 mg / L), and then the iron separation step by solid-liquid separation. The first solution obtained by subjecting to the above was further subjected to a sulfide precipitation treatment step under various conditions.
The conditions for the sulfide precipitation treatment were as follows.
First solution: 100 mL
Sulfide type: Sodium hydrosulfide (NaHS)
Addition amount of sulfide: 1 to 3 equivalents of sulfur with respect to dissolved zinc pH of the first solution during the reaction: 0.5 to 5
Acidity regulator: 3M sulfuric acid or 100g / L sodium hydroxide Treatment time: 0.5 hours after addition of sodium hydrosulfide (stirring treatment)
The addition of sodium hydrosulfide was carried out in the form of a solution by dissolving it in distilled water.
After the above-mentioned sulfide precipitation treatment step, suction filtration was performed by suction filtration with a filter paper having a pore size of 1 μm (zinc separation step), and the components of the separated second solution were analyzed by ICP emission spectrometry. The obtained analytical values were corrected for the effects of dilution with a sodium hydrosulfide solution and a pH adjuster.

As a result, when the amount of sulfide added was 1 equivalent (NaHS: 1 equivalent), although the zinc precipitate was removed, it exceeded the analysis limit (0.1 mg / L) and was incomplete, and the pH was increased. It was found that the final removal rate when increased was not stable.
On the other hand, when the amount of sulfide added is 2 equivalents (NaHS: 2 equivalents), the removal of zinc precipitates becomes remarkable, and especially under the condition that the pH of the first solution is 3 or more, the second after the zinc removal step. It was found that the zinc concentration in the solution was precipitated and removed before the analysis limit (0.1 mg / L) was reached.
Further, it was found that even when the amount of sulfide added was 3 equivalents (NaHS: 3 equivalents), the same tendency as in the case of 2 equivalents was shown, and the removal of zinc precipitate was remarkable. When the pH reached about 5, manganese also tended to precipitate.

Regarding Experiment (B) As described above, if the leachate obtained by mixing an acid solution and a reducing agent with the powder and granules of a waste dry battery and the leachate in which manganese, zinc and iron are leached is first subjected to an oxidation treatment, air exposure is performed. By performing the simple oxidation treatment, the solution can be obtained by precipitating and separating and removing the iron component before it becomes less than the analysis limit (iron removal step). Then, if the first solution is subjected to a sulfide precipitation treatment step of allowing sulfide to act, the zinc component can be precipitated and removed to a level below the analysis limit (zinc removal step).

As described above, according to the experiments (A) and (B), iron and zinc were both precipitated and separated and removed to less than the analysis limit by going through the zinc removing step and the iron removing step, regardless of the step sequence. It was found that a high-purity manganese-containing solution can be easily produced by simply performing a simple process.

The present invention has been completed with further studies based on such findings. That is, the gist of the present invention is as follows.
(1) A sorting step for selecting manganese dry batteries and / or alkaline manganese dry batteries from waste batteries, and
A crushing / sieving step of crushing and sieving the manganese dry cell and / or the alkaline manganese dry cell selected in the sorting step to obtain powder or granular material.
An acid solution and a reducing agent are mixed with the powder or granular material obtained in the crushing / sieving step, and manganese, zinc and iron contained in the powder or granular material are leached from the powder or granular material to cause manganese. An acid leaching step to obtain a leachate containing ions, zinc ions and iron ions,
A solid-liquid separation step for separating the leachate obtained in the acid leaching step and other leaching residues, and a solid-liquid separation step.
A manganese extraction step of removing the zinc ions and iron ions from the leachate separated in the solid-liquid separation step to obtain a solution containing the manganese ions.
Is a method of recovering manganese from waste batteries, in this order.
The manganese extraction step
A zinc removal step including a sulfide precipitation treatment step of allowing a sulfide to act on the zinc ions to precipitate the zinc ions, and a zinc separation step of separating the obtained zinc-containing precipitate;
An iron removal step including an oxidation treatment step of oxidizing the iron ions to precipitate the iron ions, and an iron separation step of separating the obtained iron-containing precipitate;
A method for recovering manganese from a waste dry battery, which comprises recovering manganese contained in the waste dry battery as a high-purity manganese-containing solution by containing the following in no particular order.

(2) In (1), the manganese extraction step is performed in the order of the zinc removing step and then the iron removing step.
In the zinc removal step, a sulfide precipitation treatment step of allowing sulfide to act on the leachate to precipitate zinc ions in the leachate is performed, and then the zinc-containing precipitate and manganese obtained in the sulfide precipitation treatment step are performed. Solid-liquid separation from the first solution containing ions and iron ions was performed.
In the iron removing step, iron obtained in the oxidation treatment step is performed after performing an oxidation treatment step of oxidizing the first solution obtained in the zinc removing step to precipitate iron ions in the first solution. A method for recovering manganese from a waste dry battery, which comprises solid-liquid separation of a second solution containing manganese ions and a contained precipitate.

(3) A method for recovering manganese from a waste dry cell according to (2), wherein the leachate is adjusted to pH: 2 or more and 6 or less in the sulfide precipitation treatment step.

(4) In (2) or (3), in the oxidation treatment step, air exposure is performed to the first solution containing the manganese ion and iron ion, or an oxidizing agent is further applied to the first solution. A method for recovering manganese from a waste dry cell, which comprises adding the first solution and adjusting the pH of the first solution to 3 or more and 7 or less.

(5) In (1), the manganese extraction step is performed in the order of the iron removing step and then the zinc removing step.
In the iron removing step, after performing an oxidation treatment step of oxidizing the leachate and precipitating iron ions in the leachate, the iron-containing precipitate obtained in the oxidation treatment step, manganese ion and zinc ion are contained. Solid-liquid separation from the first solution
In the zinc removal step, a sulfide precipitation treatment step is performed in which a sulfide is allowed to act on the first solution obtained in the iron removal step to precipitate zinc ions in the first solution, and then the sulfide precipitate. A method for recovering manganese from a waste dry battery, which comprises solid-liquid separation of a zinc-containing precipitate obtained in the treatment step and a second solution containing manganese ions.

(6) In the sulfide precipitation treatment step, manganese recovery from a waste dry cell is characterized in that the first solution containing manganese ions and zinc ions is adjusted to pH: 2 or more and 6 or less. Method.

(7) From a waste dry battery according to (5) or (6), wherein in the oxidation treatment step, the leachate is aerated with air and the pH of the leachate is adjusted to 3 or more and 7 or less. Manganese recovery method.

(8) In any of (1) to (7), the acid solution in the acid leaching step is a dilute sulfuric acid having a mass% concentration of 1.4% or more and 45% or less or a dilute hydrochloric acid having a mass% concentration of 1% or more and 14% or less. A method for recovering manganese from a waste dry battery, which is characterized by being present.

(9) In any of (1) to (8), the solid-liquid ratio of the powder or granular material to the acid solution in the acid leaching step is 50 g / L or more, from a waste dry battery. Manganese recovery method.

(10) In any of (1) to (9), the reducing agent in the acid leaching step is any one of hydrogen peroxide, sodium sulfide, sodium bisulfite, sodium thiosulfate, and iron sulfate. A characteristic method for recovering manganese from waste dry batteries.

(11) In any of (1) to (10), the sulfide used in the sulfide precipitation treatment step is any one of sodium hydrosulfide, sodium sulfide, and hydrogen sulfide. How to recover manganese from waste dry batteries.

(12) A sorting device for sorting manganese dry batteries and / or alkaline manganese dry batteries from waste batteries, and
A crushing device that is charged with the manganese dry battery and / or an alkaline manganese dry battery sorted by the sorting device and subjected to crushing treatment to obtain a crushed product.
A sieving device for obtaining powder or granular material by subjecting the crushed product obtained by the crushing device to a sieving treatment.
An acid solution and a reducing agent are mixed with the powder or granular material obtained by the sieving device, and manganese, zinc and iron contained in the powder or granular material are leached from the powder or granular material to obtain manganese ions. An acid leachate to obtain a leachate containing zinc and iron ions,
A solid-liquid separation device that separates the leachate and the leachate residue obtained in the acid leachation tank, and
A group of manganese extractors that remove the zinc ions and iron ions from the leachate separated in the solid-liquid separation step to obtain a solution containing the manganese ions.
Manganese recovery equipment from waste batteries, which is equipped in this order.
The manganese extraction device group
A group of zinc removing devices including a sulfide precipitation treatment tank for allowing sulfide to act on the zinc ions to precipitate the zinc ions, and a zinc separating device for solid-liquid separating the obtained zinc-containing precipitate.
An iron removing device group including an oxidation treatment tank that oxidizes the iron ions and precipitates the iron ions, and an iron separation device that solid-liquid separates the obtained iron-containing precipitate.
Manganese recovery equipment from waste batteries, which is characterized by recovering valuable components contained in waste batteries by containing them in no particular order.

According to the present invention, the manganese component contained in the waste dry battery is almost completely separated from the carbon component, the zinc component, and the iron component, and the purity is high enough to be used as a raw material for a secondary battery electrode material, and the yield is high. , Can be easily recovered and has a remarkable effect on the industry.

It is a flow explaining the process of the manganese recovery method of this invention. It is a flow explaining one Embodiment (procedure A) of the manganese recovery method of this invention. It is a flow explaining another embodiment (procedure B) of the manganese recovery method of this invention. Amount of sulfide added to remove the precipitate of zinc and iron in the sulfide precipitation treatment step according to the flow of FIG. ) And the effect of pH conditions. It is a graph which shows the influence of pH on the iron precipitate removal in the oxidation treatment step which followed the flow of FIG. It is a schematic diagram explaining one Embodiment (configuration A) of the manganese recovery equipment of this invention. It is a schematic diagram explaining another embodiment (configuration B) of the manganese recovery equipment of this invention.

The present invention targets a waste dry cell, and separates the manganese component contained in the waste dry cell from the carbon component, the zinc component and the iron component contained in the waste dry cell together, and recovers the waste dry cell as a high-purity manganese-containing solution. It is an invention relating to the manganese recovery method and recovery equipment from manganese.
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. The following embodiments show suitable examples of the present invention, and these examples do not limit the present invention in any way.

(Manganese recovery method)
As shown in FIG. 1, the manganese recovery method of the present invention includes a sorting step, a crushing / sieving step, an acid leaching step, a solid-liquid separation step, and a manganese extraction step in this order. In addition, the manganese extraction step includes a predetermined zinc removing step and an iron removing step in no particular order.
By following the above-mentioned predetermined steps in the manganese recovery method of the present invention, components other than manganese contained in the waste dry battery can be almost completely removed in order. As a result, according to the manganese recovery method of the present invention, the manganese component can be easily recovered with high purity so that it can be used as a raw material for a secondary battery electrode material by using a waste dry battery.
Here, "almost completely" in the present specification means that the amount of the target component is less than the analysis limit, for example, 0.1, when the residue sample after a certain step is measured according to the analysis method specified in the common JIS standard. Refers to a state of less than mg / L.

Sorting process Waste batteries are generally collected in a mixed form of various types. Therefore, in the present invention, manganese dry batteries and / or alkaline manganese dry batteries are selected from the recovered waste dry batteries. In order to efficiently extract the manganese component in a later step, only the manganese dry battery may be selected, only the alkaline manganese dry battery may be selected, or both the manganese dry battery and the alkaline manganese dry battery may be selected. .. As the sorting method, any method may be used, such as manual sorting or machine sorting using equipment.

Crushing / Sieving Step Next, the manganese dry cell and / or alkaline manganese dry cell sorted in the sorting step is crushed. The purpose of crushing is to eliminate as much as possible materials containing components other than manganese and zinc from the constituent materials of manganese dry batteries and / or alkaline manganese dry batteries sorted in the sorting step.
When these waste batteries are crushed, packaging materials (iron, plastic, paper, etc.), zinc cans, which are the negative material of manganese batteries, and brass rods, which are collectors of alkaline manganese batteries, are solid in the form of foil or pieces. It becomes a thing. On the other hand, manganese dioxide, which is a positive electrode material, carbon rod, which is a current collector for manganese dry batteries, zinc powder, which is a negative electrode material for alkaline manganese dry batteries, and MnO (OH), Zn (OH) ₂ , and Mn (OH) generated by discharge. _2. Compounds such as ZnO and various electrolytic solutions become finer powders than foil-like or piece-like solids.

A crusher is usually used to crush waste batteries. The type of the crusher is not particularly limited, and for example, a type in which the solid matter such as the packaging material constituting the dry battery and the powder or granular material are well separated after crushing is preferable. Examples of such a crusher include a biaxial rotary type crusher.
The mesh size of the sieve used for sieving the above-mentioned crushed material (sieving between the foil-like or piece-like solid material and the powder or granular material) is preferably about 1 mm or more, preferably 20 mm or less, and 10 mm or less. More preferably, 3 mm or less is further preferable. The mesh size of the sieve is preferably about 1 to 20 mm, more preferably about 1 to 10 mm, and even more preferably about 1 to 3 mm. When the mesh opening of the sieve is at least the above lower limit, more powders and granules containing a manganese component can be secured. Further, when the mesh opening of the sieve is not more than the above upper limit, solid matter containing a non-target component other than manganese can be more eliminated, and the subsequent steps can be performed more efficiently.

Therefore, if the waste dry battery is crushed and then sieved using the above-mentioned open-opening sieve, large solids such as packaging materials are removed from the waste dry battery, and powder particles containing carbon mainly along with manganese and zinc components are removed. You can get the body efficiently.
As described above, the powders and granules obtained through the crushing and sieving steps are the main constituent materials of the manganese dry battery and / or the alkaline manganese dry battery, such as manganese dioxide, carbon, zinc chloride or ammon chloride, caustic potash, and further. It is a powder and granules in which MnO (OH), Zn (OH) ₂ , Mn (OH) ₂ , ZnO, etc. generated by discharge are mixed. Normally, an iron component is inevitably mixed in the powder or granular material.

Acid leaching step In the acid leaching step, an acid solution and a reducing agent are mixed with the powder or granular material obtained in the crushing / sieving step, and the powder or granular material is subjected to acid leaching treatment. By this acid leaching treatment, a leachate in which mainly manganese component, zinc component and iron component are leached into an acid solution can be obtained from the powder or granular material. The carbon component remains as a solid state leaching residue.

The acid used in the acid solution may be a general acid, and sulfuric acid, nitric acid, hydrochloric acid or other acids can be used. Although it can be appropriately selected depending on the price and purpose, it is preferable to use sulfuric acid or hydrochloric acid as the acid solution in consideration of cost and ease of procurement.
When sulfuric acid is used, it is preferable to use dilute sulfuric acid having a sulfuric acid concentration of 1.4% or more and 45% or less at a mass% concentration. More specifically, the sulfuric acid concentration is preferably 1.4% or more, more preferably 2% or more, further preferably 5% or more, preferably 45% or less, more preferably 30% or less, still more preferably 25% or less. The sulfuric acid is more preferably dilute sulfuric acid having a concentration of 2% or more and 30% or less, and further preferably dilute sulfuric acid having a concentration of 5% or more and 25% or less.
When hydrochloric acid is used, it is preferable to use dilute hydrochloric acid having a mass% concentration and a hydrochloric acid concentration of 1% or more and 14% or less. More specifically, the hydrochloric acid concentration is preferably 1% or more, more preferably 2% or more, preferably 14% or less, and more preferably 8% or less. The hydrochloric acid is more preferably dilute hydrochloric acid having a concentration of 2% or more and 8% or less.
Any commercially available sulfuric acid or hydrochloric acid can be used, but the cost of the acid can be reduced by diluting the waste acid for industrial use or having a small amount of harmful metal components. The "mass% concentration" here is a value obtained by dividing the mass of the acid in the acid solution by the mass of the entire solution and multiplying it by 100.

Regardless of which acid is used, the acid concentrations required for leaching the manganese component, zinc component and iron component are the solid-liquid ratio of the powder or granular material to the acid solution, the amount of the powder or granular material, and the powder or granular material. It varies depending on the content of manganese, zinc and iron, the morphology of manganese and zinc in the granular material, and the like. Therefore, the optimum acid concentration can be determined by conducting a preliminary experiment assuming an actual machine in advance.

In the acid leaching step of the present invention, an acid solution and a reducing agent are mixed with the powder or granular material. The reason for adding the reducing agent is to allow the manganese component contained in the powder or granular material to be almost completely leached out. The morphology of manganese contained in the powder is predicted to be MnO ₂ , Mn ₂ O ₃ , Mn O (OH), Mn ₃ O ₄ , Mn (OH) ₂ , etc., of which only acid dissolves. Is only a part of Mn (OH) ₂ and Mn ₃ O ₄ , and Mn O ₂ is considered to be hardly soluble in acid. Manganese dissolves in an acid when it has a divalent valence, and in order to dissolve manganese which has a valence such as trivalent or tetravalent in an acid, it has a divalent valence. It needs to be reduced. Therefore, a reducing agent is required as a substance that supplies electrons for reduction. The amount of the reducing agent added is not particularly limited, but since it depends on the form of manganese contained in the powder or granular material, about 5 to 200 g / L with respect to the acid solution is sufficient.

Examples of the reducing agent include hydrogen peroxide H ₂ O ₂ , sodium sulfide Na ₂ S ・ 9H ₂ O, sodium bisulfite Na HSO ₃ , sodium thiosulfite Na ₂ S ₂ O ₃ , and iron sulfate FeSO ₄・ 7H ₂ O. However, any of the various commonly used reducing agents can be applied. Sulfur-based reducing agents may generate corrosive gases such as sulfurous acid gas and hydrogen sulfide gas, so caution is required from the viewpoint of safety and the like. From this point of view, the reducing agent is preferably hydrogen peroxide H ₂ O ₂ .
As for the zinc component contained in the powder or granular material, almost all of the zinc component is dissolved (leached) by increasing the acid concentration regardless of the presence or absence of the reducing agent.

From the viewpoint of improving the efficiency of the acid leaching process, the solid-liquid ratio (powder / granules (g) / acid solution (L)) of the powder / granules to the acid solution in the acid leaching step should be 50 g / L or more. preferable. On the other hand, if the solid-liquid ratio exceeds 800 g / L, the viscosity may increase and handling problems may occur, or the yield during the solid-liquid separation process may deteriorate. Therefore, the solid-liquid ratio is preferably 800 g / L or less. Further, although a sufficient effect can be obtained even at room temperature (around 15 to 25 ° C.) as the treatment temperature (atmospheric temperature or acid solution temperature) of the acid leaching treatment, heating may be performed. The heating temperature can be, for example, 60 ° C to 80 ° C. It can be expected that the reaction efficiency will be improved by heating. The treatment time for the acid leaching treatment is preferably 5 minutes or more, preferably 6 hours or less.

Solid-liquid separation step In the solid-liquid separation step, the leachate obtained in the acid leaching step and the leaching residue are separated into solid and liquid. The separated leachate contains manganese ions, zinc ions and iron ions. On the other hand, the leaching residue of the separated solid is mainly the result of residual carbon. Thereby, the manganese component, the zinc component and the iron component contained in the powder or granular material can be separated from the carbon.
The solid-liquid separation means is not particularly limited. For the solid-liquid separation step, it is preferable to use a commonly used means, for example, a means selected from gravity sedimentation separation, filtration, centrifugation, filter press, membrane separation and the like.

Manganese Extraction Step In the present invention, a predetermined manganese extraction step of removing zinc ions and iron ions from the leachate separated in the solid-liquid separation step to obtain a solution containing manganese ions with high purity (manganese-containing solution). Need to be done. Specifically, the manganese extraction step includes a predetermined zinc removing step and an iron removing step in no particular order. More specifically, the zinc removal step included in the manganese extraction step is a sulfide precipitation treatment step in which sulfide is allowed to act on zinc ions to precipitate zinc ions, and a zinc separation step in which the obtained zinc-containing precipitate is separated. And include. Further, the iron removal step included in the manganese extraction step includes an oxidation treatment step of oxidizing iron ions to precipitate iron ions and an iron separation step of separating the obtained iron-containing precipitate.
As described above, in the manganese extraction step, zinc ions and iron ions are selectively precipitated, respectively, and the zinc ions and iron ions are surely removed from the leachate, whereby the manganese component, which is the target component, is finally obtained with high purity. Can be obtained at.

In the manganese extraction step, a zinc removal step including a sulfide precipitation treatment step for preferentially precipitating zinc ions and a zinc separation step may be performed first (procedure A), or oxidation for preferentially precipitating iron ions. The iron removal step including the treatment step and the iron separation step may be performed first (procedure B). From the viewpoint of facilitating the simplification of the process, it is preferable to perform the iron removing step first (procedure B). In procedure A, a mixture of a zinc-containing precipitate and a first solution containing manganese ions and iron ions is obtained from the leachate, and then these are separated. Further, in procedure B, after obtaining a mixture of the iron-containing precipitate and the first solution containing manganese ion and zinc ion from the leachate, these are separated.

Zinc removal step (procedure A)
In the zinc removal step in the procedure (A), the leachate separated in the solid-liquid separation step is first subjected to a sulfide precipitation treatment step. In this sulfide precipitation treatment step, sulfide is allowed to act on the leachate to precipitate mainly zinc ions as zinc sulfide among the ions contained in the leachate, so that the zinc component can be removed from the leachate first. By this treatment, a mixture of a first solution containing manganese ions and iron ions and a zinc-containing precipitate is obtained from the leachate.

The leachate separated in the solid-liquid separation step contains manganese ion, zinc ion, and iron ion, and when sulfide acts on the leachate, the divalent metal ion contained is sulfide ion S ^2- . The reaction produces sulfide and precipitates. The ease of precipitation of this sulfide depends on the solubility product K _SP . The solubility products of manganese, zinc and iron sulfides are shown below.
MnS: K _SP = 2.5 × 10 ^-10
ZnS: K _SP = 1.6 × 10 ^-24
FeS: K _SP = 6.3 × 10 ^-18
(Lange, NA: Lange's Handbook of Chemistry. Thirteenth edition 1985)
The smaller the solubility product K _SP value, the easier it is to form sulfides. Therefore, among manganese, zinc, and iron, zinc (Zn) is most likely to form sulfides. Therefore, when a sulfide is allowed to act on a leachate containing manganese, zinc, and iron ions, zinc (Zn) can be selectively precipitated as a sulfide. Then, by adjusting the concentration of sulfide ions and the pH of the leachate, the zinc ion concentration in the leachate can be easily reduced to less than the analysis limit (0.1 mg / L).

In the present invention, sulfide is allowed to act on the leachate separated in the solid-liquid separation step, and zinc ions are mainly precipitated and removed as sulfide. Examples of the sulfide to act include sodium hydrosulfide NaHS, sodium sulfide NaS, hydrogen sulfide H ₂ S and the like. Since hydrogen sulfide is a gas, it needs to be aerated.

The amount of sulfide to act is preferably 1.1 equivalents or more and 5 equivalents or less as sulfur S with respect to dissolved zinc. The amount of sulfide is preferably 1.1 equivalents or more, more preferably 2 equivalents or more, more preferably 5 equivalents or less, more preferably 3 equivalents or less, still more preferably less than 3 equivalents, as sulfur S with respect to dissolved zinc. When the amount of sulfide is at least the above lower limit, zinc ions can be reliably precipitated. Further, when the amount of sulfide is not more than the above lower limit, unintended precipitation of manganese ions can be suppressed, and the amount of sulfide acting can be prevented from becoming excessive and economically disadvantageous.

Further, the pH of the leachate when the sulfide is allowed to act is preferably 2 or more and 6 or less. If the pH of the solution is too low, less than 2, the precipitation of zinc ions will be insufficient, while if it is too high, more than 6, the amount of manganese precipitation will increase and the manganese yield will decrease. Therefore, the pH of the leachate is preferably 2 or more, more preferably 3 or more, more preferably 6 or less, more preferably 5 or less, still more preferably less than 5, preferably pH 2 or more and 6 or less, more preferably pH 2 or more and 5 or less. More preferably, the pH is 3 or more and 5 or less, and more preferably, the pH is 3 or more and less than 5.

Subsequently, in the zinc removal step in the procedure (A), the mixture obtained in the above-mentioned sulfide precipitation treatment step is separated into a first solution and a zinc-containing precipitate (zinc separation step), and the zinc component is removed. ..
More specifically, the first solution containing manganese ions and iron ions obtained in the sulfide precipitation treatment step is separated from the zinc-containing precipitate in which zinc sulfide is mainly precipitated. As a result, the zinc component can be easily separated from the mixture after the sulfide precipitation treatment step, and a first solution containing a manganese component and an iron component can be obtained.
In the above-mentioned sulfide precipitation treatment, a part of iron (Fe) may be removed from the solution by precipitation. In this case, if the iron content is less than the preset iron content, the treatment may be completed at this stage. However, in the procedure (A), an iron removing step described later is further performed in order to further separate and remove iron to obtain a high-purity manganese component.
The separation means is not particularly limited, and the solid-liquid separation step described above may be followed.

Iron removal step (procedure A)
In the procedure (A), an iron removing step is performed following the zinc removing step described above. In the iron removal step in the procedure (A), first, the first solution obtained in the previous zinc removal step is subjected to an oxidation treatment step, and the iron ions in the first solution are used as an iron-containing precipitate to separate and remove the iron component. enable. By this treatment, a mixture of the second solution (manganese-containing solution) containing manganese ions with high purity and the iron-containing precipitate can be obtained from the first solution.

As the oxidation treatment method, the oxidation treatment method in the procedure (B) described later may be followed, including the suitable pH of the first solution. Here, when the first solution obtained through the sulfide precipitation treatment step is exposed to air under practical conditions, the iron component in the first solution may not be completely precipitated. This is because the sulfide added in the sulfide precipitation treatment step acts as a reducing agent in this step. This reducing agent consumes oxygen supplied by air aeration, and depending on the amount of air aeration, the amount of oxygen to be added is insufficient, and iron components that cannot react with oxygen and cannot precipitate remain in the treated solution. Is considered to be. If air aeration is continued, the sulfide becomes sulfate ions, and finally the solution becomes an oxidizing atmosphere, and the iron component also precipitates. However, the aeration time (reaction time) becomes long, which is not practical.

Therefore, in the oxidation treatment step in the procedure (A), it is preferable to apply air aeration and then add an oxidizing agent as a finish oxidation treatment. The amount of the oxidant added is preferably adjusted so that the redox potential (vs. SHE) is measured and the redox potential is 550 mV or more. Examples of the oxidizing agent include hydrogen peroxide and potassium permanganate.
If the zinc removal step is performed, the iron component is left for an appropriate period, and then the oxidation treatment step is performed, the iron component can be sufficiently precipitated only by air aeration without performing the finish oxidation treatment. This is because hydrogen sulfide, which is a reducing substance, in the first solution generated in the sulfide precipitation treatment step in the previous stage is released into the air, and the first solution is easily oxidized, that is, the redox potential is easily increased. It is thought that it is caused by becoming. The appropriate leaving period varies depending on the storage condition such as whether it is a closed system or an open system, so it cannot be said unconditionally, but it is estimated to be about several days to one week.

Then, in the iron removal step in the procedure (A), the mixture obtained in the above-mentioned oxidation treatment step is separated into a second solution and an iron-containing precipitate (iron separation step) to remove the iron component. In this way, a high-purity manganese-containing solution can be recovered.
The separation means is not particularly limited, and the solid-liquid separation step described above may be followed.

Iron removal step (procedure B)
In the iron removing step in the procedure (B), the leachate obtained in the solid-liquid separation step is first subjected to an oxidation treatment. In this oxidation treatment, the leachate is oxidized to precipitate iron ions among the ions contained in the leachate as an iron-containing precipitate, so that the iron component can be removed from the leachate first. By this treatment, a mixture of a first solution containing manganese ions and zinc ions and an iron-containing precipitate is obtained from the leachate.

As the oxidation treatment method, any of the usual oxidation treatment methods can be applied, but in the oxidation treatment step of the present embodiment, only air aeration, which is an inexpensive oxidation treatment method, is sufficient. As the conditions for air aeration, it is economical to set normal practical conditions (infusion amount: (0.1 times to 1 times the amount of exudate) / minute, aeration time: 15 to 60 minutes). It is preferable from the above viewpoint.

The oxidation treatment is preferably performed by adjusting the pH of the leachate with a pH adjuster. If the pH of the leachate is too low, the iron component will not precipitate. On the other hand, if the pH of the leachate is too high, the manganese component will also precipitate at the same time. Therefore, it is preferable to adjust the leachate to a pH range of 3 to 7. The leachate is more preferably pH 5 or higher, more preferably pH 6 or lower, and even more preferably around pH 5 to pH 6. As a result, the iron component can be precipitated / separated and removed from the leachate until it becomes less than the analysis limit, and a high-purity manganese-containing solution having a low impure content can be obtained.

Subsequently, in the iron removal step in the procedure (B), the mixture obtained in the above-mentioned oxidation treatment step is separated into a first solution and an iron-containing precipitate that can mainly contain iron hydroxide (iron separation step). Thereby, the iron component can be easily separated and removed from the mixture after the oxidation treatment step, and the first solution containing the manganese component and the zinc component can be obtained.
The separation means is not particularly limited, and the solid-liquid separation step described above may be followed.

Zinc removal step (procedure B)
In the procedure (B), a zinc removing step is performed following the iron removing step described above. In the zinc removal step in the procedure (B), a sulfide is allowed to act on the first solution obtained in the previous iron removal step, and zinc ions among the ions in the first solution are mainly precipitated as zinc sulfide to form a zinc component. Can also be removed from the first solution. By this treatment, a mixture of the second solution (manganese-containing solution) containing manganese ions with high purity and the zinc-containing precipitate can be obtained from the first solution.

The first solution separated in the previous iron removal step contains manganese ions and zinc ions, and when sulfide is allowed to act on the first solution, it is the same as the sulfide precipitation treatment step in the above procedure (A). According to a similar mechanism, the zinc component selectively precipitates as a sulfide. Then, by adjusting the amount of sulfide to be added, the concentration of sulfide ions, and the pH of the first solution, the zinc ion concentration in the first solution can be easily reduced below the analysis limit (0.1 mg / L). Can be done.
As the sulfide precipitation treatment method, the sulfide precipitation treatment method in the above-mentioned procedure (A) may be followed, including the type of sulfide, the amount of sulfide, and the suitable pH of the first solution. The first solution is particularly preferably pH: 4.

Then, in the zinc removal step in the procedure (B), the mixture obtained in the above-mentioned sulfide precipitation treatment step is separated into a second solution and a zinc-containing precipitate (zinc separation step), and the zinc component is removed. In this way, a high-purity manganese-containing solution can be recovered.
The separation means is not particularly limited, and the solid-liquid separation step described above may be followed.

By sequentially going through each of the above steps, the carbon component, zinc component, and iron component other than the manganese component contained in the waste dry battery can be almost completely separated and removed, and the zinc component and iron component are reduced to less than the analysis limit. Can be recovered as a manganese-containing solution.
The obtained manganese-containing solution may be mixed with other metals and then subjected to an alkali precipitation treatment or the like to be used as a raw material for a secondary battery electrode material.

(Manganese recovery equipment)
Next, the recovery equipment of the present invention will be described. The recovery equipment of the present invention includes a sorting device, a crushing device, a sieving device, an acid leaching tank, a solid-liquid separation device, and a manganese extraction device group in this order, and has the same features and effects as the manganese recovery method of the present invention. In addition, the manganese extraction device group includes a predetermined zinc removal device group and an iron removal device group in no particular order.
The manganese recovery equipment of the present invention can be suitably used, for example, when carrying out the manganese recovery method of the present invention.

Configuration A
As one aspect of the recovery equipment of the present invention, FIG. 6 shows a configuration (A) in which the above procedure (A) can be suitably carried out. As schematically shown in FIG. 6, the recovery equipment includes a sorting device 10, a crushing device 20a, a sieving device 20b, an acid leaching tank 30, a solid-liquid separation device 40, and a sulfide precipitation treatment tank 52. , The zinc separation device 62, the oxidation treatment tank 82, the iron separation device 92, and the manganese-containing solution recovery tank 100 can be provided in this order. Here, the sulfide precipitation treatment tank 52 and the zinc separation device 62 constitute a zinc removal device group, and the oxidation treatment tank 82 and the iron separation device 92 constitute an iron removal device group. In addition, the zinc removing device group and the iron removing device group constitute a manganese extraction device group.

The sorting device 10 sorts manganese dry batteries and / or alkaline manganese dry batteries from waste dry batteries. The type of the sorting device is not particularly limited, and an example of a device for sorting using a shape, radiation, or the like can be exemplified. The waste dry batteries may be sorted by hand.
As the crusher 20a, any ordinary crusher can be applied, but it is preferable that the crusher is a biaxial rotary type crusher.
The sieving device 20b is preferably provided with a sieve having an opening of 1 mm or more and 20 mm or less. The opening of the sieving device 20b is preferably about 1 mm or more, preferably 20 mm or less, more preferably 10 mm or less, still more preferably 3 mm or less, for the same reason as described above for the manganese recovery method.

The acid leaching tank 30 is preferably a general stirring tank equipped with a stirrer in the tank because the acid solution and the reducing agent are mixed with the powder or granular material to promote the leaching reaction. Further, the sulfide precipitation treatment tank 52 is preferably a general stirring tank equipped with a stirrer in the tank because the sulfide treatment for causing the sulfide to act on the leachate is performed. Further, since the oxidation treatment tank 82 is subjected to the oxidation treatment of the first solution, it is preferable to use a general stirring tank equipped with a stirrer in the tank.

As the solid-liquid separation device 40, the zinc separation device 62, and the iron separation device 92, for example, a device selected from a gravity sedimentation separation device, a filtration device, a centrifuge separation device, a filter press device, a membrane separation device, and the like can be used. .. It is preferable that each separation device is provided with recovery tanks 70a, 72b, 72c capable of recovering the solid-liquid separated precipitate and the like.
The manganese-containing solution recovery tank 100 preferably collects the manganese-containing solution (second solution) solid-liquid separated by the iron separation device 92, can store the liquid, and is configured to be freely dispensed.

Configuration B
Further, as another aspect of the recovery equipment of the present invention, FIG. 7 shows a configuration (B) in which the above procedure (B) can be suitably carried out. As schematically shown in FIG. 7, the recovery equipment includes a sorting device 10, a crushing device 20a, a sieving device 20b, an acid leaching tank 30, a solid-liquid separation device 40, an oxidation treatment tank 53, and iron. The separation device 63, the sulfide precipitation treatment tank 83, the zinc separation device 93, and the manganese-containing solution recovery tank 100 can be provided in this order. Here, the oxidation treatment tank 53 and the iron separation device 63 constitute an iron removal device group, and the sulfide precipitation treatment tank 83 and the zinc separation device 93 constitute a zinc removal device group. Further, the iron removing device group and the zinc removing device group constitute a manganese extraction device group.

Here, a sorting device 10, a crushing device 20a, a sieving device 20b, an acid leaching tank 30, a solid-liquid separating device 40, an iron separating device 63, a zinc separating device 93, a recovery tank 70a, 73b, 73c, a manganese-containing solution recovery tank. Reference numeral 100 is as described above for the configuration A.
Since the oxidation treatment tank 53 is subjected to an oxidation treatment (air aeration) on the leachate, it is preferable to use a general stirring tank equipped with a stirrer in the tank. Since the sulfide precipitation treatment tank 83 is subjected to the sulfide precipitation treatment in which the sulfide acts on the first solution, it is preferable to use a general stirring tank equipped with a stirrer in the tank.
In the present invention, the structures, etc. of the various devices, reaction tanks, and recovery tanks constituting the recovery facility are not limited as long as they have the above-mentioned functions.

Hereinafter, the present invention will be further described based on Examples. The following examples show a suitable example of the present invention, and do not limit the present invention in any way. Further, the following examples can be carried out with modifications to the extent that can be adapted to the gist of the present invention, and such aspects are also included in the technical scope of the present invention.

(Example 1)
Preparation of Powders and Granules Manganese dry batteries and alkaline manganese dry batteries were selected from the waste dry batteries, the selected waste dry batteries were crushed, and sieved with a sieve having an opening of 2.8 mm to obtain powder and granules of the waste dry batteries. The composition of the obtained powder or granular material is shown in Table 1. In addition to the elements shown in Table 1, the obtained powder or granular material contains oxygen derived from an oxide or a hydroxide and some hydrogen.

Preparation of leachate 50 g of the obtained powder or granular material is mixed with 500 mL of an acid solution and hydrogen peroxide H ₂ O ₂ : 22.5 g as a reducing agent, and manganese, zinc and iron are leached out from the powder or granular material. Was given. The acid concentration of the acid solution was sulfuric acid concentration: 2N (mass% concentration: about 9.0%). The acid leaching treatment time was 1 hour, and the acid leaching treatment was a stirring treatment. In this case, the solid-liquid ratio, which is the ratio of the powder or granular material to the acid solution, is 100 g / L, and the amount of the reducing agent added to the acid solution is 45 g / L.

After the acid leaching treatment, the obtained leachate and the leachate residue are filtered through a filter paper having a pore size of 1 μm for solid-liquid separation (solid-liquid separation step), and the manganese concentration, zinc concentration, and iron concentration of the separated leachate are determined by ICP emission. It was quantified by the analytical method. Table 2 shows the contents (mg / L) of each component of manganese, zinc, and iron in the leachate after the solid-liquid separation step. In addition, based on the obtained analytical value, the mass of manganese in the leachate was calculated, and the ratio of the mass in the leachate to the mass in the powder or granular material (converted to each element) was calculated to obtain the leaching rate of manganese. .. The obtained manganese leaching rate was about 95%.

Preparation of first solution (zinc removal step)
Next, a sulfide precipitation treatment step was performed in which sodium hydrosulfide NaHS as a sulfide was added to the leachate separated in the solid-liquid separation step so as to have 2 equivalents of sulfur S to dissolved zinc. In addition, sodium hydrosulfide was added in the state of a solution dissolved in distilled water. In addition, the pH of the leachate during the sulfide precipitation treatment was adjusted to 4 with a pH adjusting solution (3M sulfuric acid or 100 g / L sodium hydroxide). The treatment time for the sulfide precipitation treatment was 30 minutes, and the treatment was agitation.

The mixture after the sulfide precipitation treatment was suction-filtered with a filter paper having a pore size of 1 μm, and separated into a first solution and a zinc-containing precipitate (zinc separation step). Then, the components (Mn, Zn, Fe) contained in the first solution obtained after separation were quantitatively analyzed by ICP emission spectrometry. The amount of sodium hydrosulfide solution and pH adjuster added was recorded, and the effect of dilution with these solutions was corrected from the analytical values. The obtained results are also shown in Table 2 as "the first solution after the zinc removal step".

Preparation of second solution (iron removal process)
Then, the first solution obtained through the zinc removal step was subjected to an oxidation treatment step. In the oxidation treatment step, as an oxidation treatment, first, the obtained first solution was aerated with air. The conditions for air aeration were the practical conditions of blowing amount: (same volume as the first solution amount) / minute and aeration time: 30 minutes. After aeration with air, the components contained in the first solution suction-filtered with a filter paper having a pore size of 1 μm were quantitatively analyzed by the above method. The obtained results are also shown in Table 2 as "intermediate solution after oxidation treatment".

Then, as a further oxidation treatment, an oxidizing agent was added to the first solution immediately after the above air aeration. After adjusting by adding a pH adjusting solution (3M sulfuric acid or 100g / L sodium hydroxide) so that the pH of the first solution becomes 5, hydrogen peroxide solution is used as an oxidant and the redox potential is 550 mV or more. It was added so as to be. In this way, the iron component in the first solution was precipitated as iron hydroxide so that it could be removed. The treatment time with the oxidizing agent was 30 minutes.

After the oxidation treatment step by air exposure and addition of an oxidizing agent, an iron separation step of suction filtration with a filter paper having a pore size of 1 μm was performed, and the second solution and the iron-containing precipitate were separated. The components contained in the obtained second solution were quantitatively analyzed by the above method. The amount of hydrogen peroxide solution and pH adjuster added was recorded, and the effect of dilution with these solutions was corrected from the analytical values. The obtained results are also shown in Table 2 as "the second solution after the iron removal step".

From Table 2, it can be seen that according to the procedure A of the manganese recovery method of the present invention, the zinc component and the iron component other than the manganese component contained in the waste dry battery can be separated and removed to less than the analysis limit (0.1 mg / L). The final yield of manganese component was as high as 97%. As described above, according to the present invention, it can be seen that the manganese component contained in the waste dry cell can be easily recovered as a high-purity manganese ion-containing solution with a high yield.

(Example 2)
The powder or granular material was prepared in the same manner as in Example 1 to obtain a powder or granular material having the composition shown in Table 1. Further, when the leachate was prepared in the same manner as in Example 1, the contents (mg / L) of each component of manganese, zinc, and iron in the leachate after the solid-liquid separation step were as shown in Table 3. The manganese leaching rate obtained in the same manner as in Example 1 was about 95%.

Next, when the first solution was prepared (zinc removing step) in the same manner as in Example 1, the components in the first solution after the zinc removing step were as shown in Table 3.

Then, the first solution obtained through the zinc removal step was left to stand for one week, and then subjected to an oxidation treatment step. In the oxidation treatment step, only air aeration was performed. The conditions for air aeration were the amount of blown water: (the same volume as the amount of the first solution) / minute, and the aeration time: 30 minutes. After the oxidation treatment, the components contained in the second solution obtained by suction filtration with a filter paper having a pore size of 1 μm and performing an iron separation step were quantitatively analyzed by the above method. The obtained results are also shown in Table 3 as "the second solution after the iron removal step".

From Table 3, in the manganese recovery method of the present invention, if the first solution separated by the sulfide precipitation treatment is allowed to stand for an appropriate period and then subjected to the oxidation treatment step, only air aeration is used. It can be seen that the iron component can be sufficiently separated and removed as a precipitate even in the oxidation treatment.

(Example 3)
The powder or granular material was prepared in the same manner as in Example 1 to obtain a powder or granular material having the composition shown in Table 1. Further, when the leachate was prepared in the same manner as in Example 1, the contents (mg / L) of each component of manganese, zinc, and iron in the leachate after the solid-liquid separation step were as shown in Table 4. The manganese leaching rate obtained in the same manner as in Example 1 was about 95%.

Preparation of first solution (iron removal step)
Next, the leachate separated in the solid-liquid separation step was subjected to an oxidation treatment step. In the oxidation treatment step, the obtained leachate was aerated with air to generate iron hydroxide from the iron component contained in the leachate, and the iron component could be separated and removed from the leachate as an iron-containing precipitate. The conditions for air aeration were the amount of blown water: (the same volume as the amount of exudate) / minute, and the aeration time: 30 minutes. In the oxidation treatment, the leachate was adjusted to pH: 5 with a pH adjuster (3M sulfuric acid or 100 g / L sodium hydroxide).

After the oxidation treatment, the first solution and the iron-containing precipitate were suction-filtered with a filter paper having a pore size of 1 μm, and separated into the first solution and the iron-containing precipitate (iron separation step). Then, the components (Mn, Zn, Fe) contained in the first solution obtained in the iron removal step were quantitatively analyzed by ICP emission spectrometry. The amount of the pH adjuster added was recorded, and the effect of dilution by the pH adjuster on the measured value was corrected. The concentrations (mg / L) of each component of manganese, zinc, and iron in the obtained first solution are also shown in Table 4 as "the first solution after the iron removal step".

Preparation of second solution (zinc removal step)
Then, sulfide is allowed to act on the first solution separated in the iron separation step, and zinc ions mainly contained in the first solution are precipitated as zinc sulfide (zinc-containing precipitate), and separated and removed from the first solution. A sulfide precipitation treatment step was performed to make it possible. The sulfide used was sodium hydrosulfide NaHS, which was added to dissolved zinc in an amount of 2 equivalents of sulfur S. In addition, sodium hydrosulfide was added in the state of a solution dissolved in distilled water. Further, the pH of the first solution during the sulfide precipitation treatment was adjusted to 4 with a pH adjusting solution (3M sulfuric acid or 100 g / L sodium hydroxide). The treatment time for the sulfide precipitation treatment was 30 minutes, and the treatment was agitation.

The mixture after the sulfide precipitation treatment was suction-filtered with a filter paper having a pore size of 1 μm, and separated into a second solution and a zinc-containing precipitate (zinc separation step). Then, the components of the second solution obtained after separation were quantitatively analyzed by ICP emission spectrometry. The amount of sodium hydrosulfide solution and pH adjuster added was recorded, and the effect of dilution with these solutions was corrected from the measured values. The obtained results are also shown in Table 4 as "the second solution after the zinc removal step".

From Table 4, it can be seen that according to the procedure B of the manganese recovery method of the present invention, the zinc component and the iron component other than the manganese component contained in the waste dry battery can be separated and removed to less than the analysis limit (0.1 mg / L). The final manganese component yield was as high as 94%.
As described above, according to the present invention, it can be seen that the manganese component contained in the waste dry cell can be easily recovered as a high-purity manganese ion-containing solution with a high yield.

10 Selection device 20a Crushing device 20b Sieving device 30 Acid leaching tank 40 Solid-liquid separation device 52 Sulfide precipitation treatment tank (configuration A)
53 Oxidation treatment tank (Structure B)
62 Zinc Separator (Structure A)
63 Iron Separator (Configuration B)
70a, 72b, 72c, 73b, 73c Recovery tank 82 Oxidation treatment tank (Structure A)
83 Sulfide precipitation treatment tank (Structure B)
92 Iron Separator (Structure A)
93 Zinc Separator (Structure B)
100 Manganese-containing solution recovery tank

Claims (12)

A sorting process for sorting manganese and / or alkaline manganese batteries from waste batteries,
A crushing / sieving step of crushing and sieving the manganese dry cell and / or the alkaline manganese dry cell selected in the sorting step to obtain powder or granular material.
An acid solution and a reducing agent are mixed with the powder or granular material obtained in the crushing / sieving step, and manganese, zinc and iron contained in the powder or granular material are leached from the powder or granular material to cause manganese. An acid leaching step to obtain a leachate containing ions, zinc ions and iron ions,
A solid-liquid separation step for separating the leachate obtained in the acid leaching step and other leaching residues, and a solid-liquid separation step.
A manganese extraction step of removing the zinc ions and iron ions from the leachate separated in the solid-liquid separation step to obtain a solution containing the manganese ions.
Is a method of recovering manganese from waste batteries, in this order.
The manganese extraction step
A sulfide precipitation treatment step of allowing 2 to 3 equivalents of sulfide to act on the zinc ions in the leachate having a pH of 3 or more to precipitate the zinc ions, and further, a zinc-containing precipitate obtained. A zinc separation step that separates objects, and a zinc removal step that includes;
An iron removal step including an oxidation treatment step of oxidizing the iron ions in the leachate having a pH of 5 or more to precipitate the iron ions, and an iron separation step of separating the obtained iron-containing precipitate. ;
The waste dry battery is characterized in that manganese contained in the waste dry battery is recovered as a high-purity manganese-containing solution in which the content of the zinc ion and the iron ion is less than 0.1 mg / L. Manganese recovery method from. The manganese extraction step is performed in the order of the zinc removing step and then the iron removing step.
In the zinc removal step, a sulfide precipitation treatment step of allowing sulfide to act on the leachate to precipitate zinc ions in the leachate is performed, and then the zinc-containing precipitate and manganese obtained in the sulfide precipitation treatment step are performed. Solid-liquid separation from the first solution containing ions and iron ions was performed.
In the iron removing step, iron obtained in the oxidation treatment step is performed after performing an oxidation treatment step of oxidizing the first solution obtained in the zinc removing step to precipitate iron ions in the first solution. The method for recovering manganese from a waste dry battery according to claim 1, wherein the contained precipitate and the second solution containing manganese ions are solid-liquid separated. The manganese recovery method from a waste dry cell according to claim 2, wherein the leachate is adjusted to pH: 3 or more and 6 or less in the sulfide precipitation treatment step. In the oxidation treatment step, air exposure is performed to the first solution containing manganese ions and iron ions, or an oxidizing agent is further added to the first solution, and the first solution is adjusted to pH: 5 . The manganese recovery method from a waste dry battery according to claim 2 or 3, wherein the manganese is adjusted to 7 or less. The manganese extraction step is performed in the order of the iron removing step and then the zinc removing step.
In the iron removing step, after performing an oxidation treatment step of oxidizing the leachate and precipitating iron ions in the leachate, the iron-containing precipitate obtained in the oxidation treatment step, manganese ion and zinc ion are contained. Solid-liquid separation from the first solution
In the zinc removal step, a sulfide precipitation treatment step is performed in which a sulfide is allowed to act on the first solution obtained in the iron removal step to precipitate zinc ions in the first solution, and then the sulfide precipitation is performed. The method for recovering manganese from a waste dry battery according to claim 1, wherein the zinc-containing precipitate obtained in the treatment step and the second solution containing manganese ions are solid-liquid separated. The method for recovering manganese from a waste dry cell according to claim 5, wherein in the sulfide precipitation treatment step, the first solution containing the manganese ion and the zinc ion is adjusted to pH: 3 or more and 6 or less. The manganese recovery method from a waste dry cell according to claim 5 or 6, wherein in the oxidation treatment step, the leachate is aerated with air and the pH of the leachate is adjusted to 5 or more and 7 or less. .. Any of claims 1 to 7, wherein the acid solution in the acid leaching step is dilute sulfuric acid having a mass% concentration of 1.4% or more and 45% or less or dilute hydrochloric acid having a mass% concentration of 1% or more and 14% or less. The method for recovering manganese from a waste dry battery according to item 1. The manganese recovery from the waste dry cell according to any one of claims 1 to 8, wherein the solid-liquid ratio of the powder or granular material to the acid solution in the acid leaching step is 50 g / L or more. Method. The reducing agent in the acid leaching step is any one of hydrogen peroxide, sodium sulfide, sodium bisulfite, sodium thiosulfate, and iron sulfate, according to any one of claims 1 to 9. The method for recovering manganese from the described waste dry battery. The waste dry battery according to any one of claims 1 to 10, wherein the sulfide used in the sulfide precipitation treatment step is any one of sodium hydrosulfide, sodium sulfide, and hydrogen sulfide. Manganese recovery method from. A sorting device that sorts manganese dry batteries and / or alkaline manganese dry batteries from waste batteries,
A crushing device that is charged with the manganese dry battery and / or an alkaline manganese dry battery sorted by the sorting device and subjected to crushing treatment to obtain a crushed product.
A sieving device for obtaining powder or granular material by subjecting the crushed product obtained by the crushing device to a sieving treatment.
An acid solution and a reducing agent are mixed with the powder or granular material obtained by the sieving device, and manganese, zinc and iron contained in the powder or granular material are leached from the powder or granular material to obtain manganese ions. An acid leachate to obtain a leachate containing zinc and iron ions,
A solid-liquid separation device that separates the leachate and the leachate residue obtained in the acid leachation tank, and
A group of manganese extractors that remove the zinc ions and iron ions from the leachate separated in the solid-liquid separation step to obtain a solution containing the manganese ions.
Manganese recovery equipment from waste batteries, which is equipped in this order.
The manganese extraction device group
A group of zinc removing devices including a sulfide precipitation treatment tank for allowing sulfide to act on the zinc ions to precipitate the zinc ions, and a zinc separating device for solid-liquid separating the obtained zinc-containing precipitate.
An iron removing device group including an oxidation treatment tank that oxidizes the iron ions and precipitates the iron ions, and an iron separation device that solid-liquid separates the obtained iron-containing precipitate.
The waste dry battery is characterized in that manganese contained in the waste dry battery is recovered as a high-purity manganese-containing solution in which the content of the zinc ion and the iron ion is less than 0.1 mg / L. Manganese recovery equipment from.

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