JP7004091B2 - 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 is 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 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, and remove insoluble matter (carbon powder, etc.). After making a mixed aqueous solution of manganese chloride and zinc chloride and removing impurities by purifying the solution, heat and concentrate, add perchloric acid to the concentrate and heat, and 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. It is a technology to do. 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 manganese dioxide and zinc chloride obtained by the technique described in Patent Document 2 are new. It is said that it can be used in the manufacture of manganese dry batteries.

Further, in Patent Documents 3 to 5, an acid or an acid and a reducing agent are allowed to act on manganese-containing powders obtained by crushing and sieving waste dry batteries, and ozone is further allowed 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 manganese 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, and an alkaline precipitation treatment step is performed in which the zinc ions in the zinc ion-containing solution are used as a zinc-containing precipitate to remove the zinc component contained in the waste dry battery. It 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 maker. Is only recovering some of the iron and carbon contained in the waste batteries. Most of the valuable metals contained in the waste batteries are not recovered and are sent to landfills 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 are still problems such as disadvantages in terms of economy.

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 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 commonly used as impurities in the solution. All of the analyzes used refer to manganese-containing solutions that are below the analysis limit, for example, less than 0.1 mg / L.

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 under the sieve. Be separated. 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 a means for separating impurities, which is 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 unintended components (impurities) from powders and granules obtained by selecting one or both of manganese dry batteries and alkaline manganese dry batteries from waste batteries, and further crushing and sieving them. Diligently examined whether to remove.
As a result, the present inventors have come up with the idea that the powder or granular material obtained as described above is first subjected to a predetermined heat treatment. When the above-mentioned powder or granular material is heat-treated in an inert gas atmosphere or a reducing atmosphere (that is, in a non-oxidizing atmosphere), the present inventors can obtain zinc contained in the powder or granular material with high efficiency and high efficiency. It was found that it can be easily removed as pure zinc.
Further, the present inventors apply an acid and a reducing agent to the heat-treated powders and granules to obtain a leachate in which manganese, iron, and residual zinc are leached out, and then the leachate is used to obtain a leachate. By selectively precipitating and separating the remaining zinc component and the iron component according to a predetermined procedure, a high-purity manganese solution can be easily and inexpensively obtained regardless of the order of the precipitation and separation steps. Was found.

As a more specific embodiment, the present inventors first treat zinc ions remaining in the leachate as sulfides (zinc-containing sulfides) by allowing a sulfide such as sodium hydrosulfide NaHS to act on the leachate. It was found that the zinc component can be further removed from the leachate by performing a sulfide precipitation treatment step of selectively precipitating and a zinc separation step of separating the obtained zinc-containing precipitate (zinc removal step in procedure A). .. Then, the present inventors have found that the zinc ion concentration in the solution (first solution) left after the zinc removal step can be easily reduced to less than the analysis limit of 0.1 mg / L. In addition, the present inventors have also found that by adjusting the amount of sulfide to act on, the concentration of sulfide ions, and the pH of the leachate, the zinc component remaining from the leachate can be better separated.
Then, if the first solution separated from zinc to below the analysis limit is further subjected to an oxidation treatment step and iron ions are further separated as an iron-containing precipitate (iron separation step), it is left after the iron component is separated. It was found that a high-purity manganese solution can be easily and inexpensively obtained as the solution (second solution) (iron removal step in procedure A).

Further, as a specific other embodiment, when the iron component is removed prior to the remaining zinc component, the present inventors oxidize the obtained leachate 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 a hydroxide 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 significantly reduced. 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 remaining zinc ions are further separated as a zinc-containing precipitate. It has been found that a high-purity manganese solution can be easily and inexpensively obtained as the solution (second solution) left after separation.

First, the results of the experiments (A) and (B) conducted by the present inventors according to the above procedures (A) and (B) will be described.

Experiment (A)
From the waste batteries, manganese dry batteries and alkaline manganese dry batteries were sorted (sorting step), and further crushed and sieved to obtain powders and granules.
Graphite was further added to the obtained powder or granular material as a reducing agent in a graphite mixing ratio (: graphite / powder or granular material) so that the mass ratio was in the range of 0 to 1. Then, the powder or granular material containing graphite in various ratios was subjected to a heat treatment step of a heating temperature of 1000 ° C. and a heating time of 30 minutes in a heating furnace having a nitrogen gas atmosphere, which is a non-oxidizing atmosphere. The weight and zinc content of the powder and granules before and after the heat treatment are measured, and the zinc removal rate by the heat treatment is determined according to the following formula from the difference in the zinc content contained in the powder and granules before and after the heat treatment. Calculated.
Zinc removal rate [%] = (Zn content in the powder or granular material before heat treatment [kg] -Zn content in the powder or granular material after heat treatment [kg]) x 100 / Powder or granular material before heat treatment Zn content in [kg]
The obtained results are shown in FIG. 4 as a graph showing the relationship between the blending ratio of the reducing agent (graphite) and the zinc removal rate in the heat treatment step.

From FIG. 4, it can be seen that the zinc removal rate is 84% even when the graphite blending ratio is 0 (that is, when graphite as a reducing agent is not blended in the heat treatment step). This is presumed to be due to the following mechanism. That is, ZnO is first reduced to Zn (zinc) by the reaction between the graphite contained in the powder or granular material derived from the dry cell and ZnO. Since the boiling point of zinc is around 900 ° C, when the heating temperature is 1000 ° C, the produced zinc is volatilized and removed from the powder or granular material as zinc vapor.
Further, from FIG. 4, it can be seen that the zinc removal rate increases as the mixing ratio of graphite is increased, and a maximum zinc removal rate of 96% can be obtained. However, judging from FIG. 4, it can be seen that even if the graphite blending ratio increases beyond 0.5, a significant improvement in the zinc removal rate cannot be expected.

The heat treatment of the powder or granular material is performed in a non-oxidizing atmosphere having an inert atmosphere or a reducing atmosphere. In an oxidizing atmosphere such as an air atmosphere, a part of the graphite contained in the powder or granular material or added to the powder or granular material reacts with oxygen in the air instead of ZnO and burns. Therefore, the reduction of ZnO to zinc is inhibited. In addition, most of the zinc contained in the powder or granular material is volatilized and removed by the heat treatment, but as can be seen from FIG. 4, a small amount of zinc component usually remains in the heat-treated powder or granular material. do.

Next, the acid solution and the reducing agent are allowed to act on the heat-treated powder or granular material, and the manganese component, the iron component, and the remaining zinc component contained in the powder or granular material are leached into the leachate. Treated (acid leaching step). In addition, the effect of the amount of the reducing agent added on the leaching rate of the manganese component in this acid leaching step was investigated.
Manganese dry batteries and alkaline manganese dry batteries are selected from the waste batteries, and the powders and granules obtained by further crushing and sieving are subjected to a nitrogen atmosphere (inert atmosphere) without adding a reducing agent such as graphite. Heating temperature: Heat treatment was performed at 1000 ° C. for 30 minutes. An acid leaching step of mixing an acid solution and a reducing agent was carried out in the obtained heat-treated powders and granules. The acid leaching treatment conditions were as follows. By this acid leaching step, a mixture of a leachate containing at least manganese ion, residual zinc ion, iron ion, and other leaching residue was obtained.
Acid solution: Sulfuric acid 50mL
Sulfuric acid concentration: 1.5 mol / L (mass% concentration about 13.2%)
Reducing agent: 35% hydrogen peroxide solution H ₂ O ₂
Reducing agent addition amount: 0g (0g / L), 0.56g (11g / L), 1.1g (22g / L), 1.7g (33g / L), 2.2g (45g / L)
Acid leaching treatment time: 1 hour (stirring treatment)
Solid-liquid ratio of powder and acid solution: 100 g / L

After the acid leaching treatment, the obtained mixture was filtered through 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). The manganese concentration in the separated leachate was quantified by ICP emission spectrometry. Next, based on the obtained measured values, the mass of manganese in the leachate was determined, and the ratio of the mass of manganese in the leachate (in terms of manganese element) to the mass of manganese contained in the powder and granules after the heat treatment was calculated. , Manganese leaching rate. The obtained results are shown in FIG.

From FIG. 5, the manganese leaching rate is approximately 100% regardless of the amount of the reducing agent (hydrogen peroxide solution) added, and the manganese component contained in the powder or granular material after the heat treatment is leached out by the acid leaching step. It can be seen that the entire amount has been exuded. As is clear from FIG. 6, the morphology of manganese contained in the powder or granular material after the heat treatment step is mainly MnO. MnO dissolves only in acid. Therefore, the present inventors have found that if the powder or granular material is subjected to a heat treatment step, almost all of the manganese component contained in the powder or granular material can be leached without adding a reducing agent in the acid leaching step.
Depending on the amount of graphite contained / added in the powder or granular material before the heat treatment, and the heating conditions such as the heating temperature and the heating time, MnO ₂ , Mn ₂ O ₃ , and Mn ₃ O ₄ even after the heat treatment. In some cases, the Mn form remains, and the entire amount of manganese is not leached out only with the acid. In such a case, by adding a reducing agent (hydrogen peroxide solution), manganese existing as MnO ₂ , Mn ₂ O ₃ , and Mn ₃ O ₄ can also be leached as Mn ²⁺ .

By the heat treatment, most of the zinc contained in the powder or granular material is volatilized and removed, but as described above, some zinc remains in the heat-treated powder or granular material. Therefore, the powder or granules after the heat treatment are subjected to an acid leaching treatment in which an acid and, if necessary, a reducing agent are further acted to leach the remaining zinc component, and then the sulfide is further added to the obtained leachate. If the precipitation treatment is performed, the remaining zinc component can be selectively and sufficiently precipitated as will be described in detail later. As a result, I came up with the idea that the zinc component can be removed reliably, easily, and inexpensively.

The heat-treated powders and granules that have been heat-treated without blending graphite are subjected to acid leaching treatment in which only an acid solution acts (acid leaching step), and then the leachate and the precipitate are filtered through a filter paper having a pore size of 1 μm. A solid-liquid separation step was performed to obtain a leachate. The acid concentration of the acid solution was 1.5 mol / L (mass% concentration: about 13.2%), and the acid leaching treatment time was 1 hour. By this acid leaching step and solid-liquid separation step, a leaching solution containing at least manganese ion, zinc ion and iron ion was obtained.
When the manganese concentration, zinc concentration, and iron concentration in the obtained leachate were quantitatively analyzed by the ICP emission analysis method, the manganese concentration was 66198 mg / L, the zinc concentration was 5031 mg / L, and the iron concentration was 1131 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
pH adjuster: 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 a sodium hydrosulfide solution and a pH adjuster. The obtained results are shown in FIG. FIG. 7 does not show the analysis result of manganese.

From FIG. 7 (a), 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. 7B, 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. 7 (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. 7, it can be seen that the zinc precipitation step also removes the iron precipitate. As shown in FIG. 7B, 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 to 10 mg / L. Under this condition shown in FIG. 7B, the manganese concentration also began to decrease to about 55000 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. 7 (c) 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. 7 (c), it can be seen that the removal of the iron precipitate is particularly remarkable when the pH is 5, and the iron is removed until it reaches about 1 mg / L. 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 66198 mg / L, and the zinc concentration was 5031 mg. / L, iron concentration was 1131 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
Acidity regulator: 3M sulfuric acid or 100g / L sodium hydroxide Here, the aeration amount and aeration time are the usual practical conditions (aeration amount: 0.1 to 1 times the amount / minute with respect to the solution amount, aeration time. : 15-60 minutes).
Then, the total amount of the leachate after air aeration is suction-filtered with a filter paper having a pore size of 1 μm to separate it into solid and liquid (iron separation step), and the component concentration (zinc, iron, manganese) of the separated first solution is determined by the ICP emission analysis method. Measured at. The measured values obtained were corrected for the effect of dilution with a pH adjuster. The obtained results are shown in FIG. Since precipitation of manganese and zinc by the oxidation treatment step was hardly confirmed, FIG. 8 shows only the iron concentration in the first solution after the iron removal step (oxidation treatment step and iron separation step).

From FIG. 8, it can be seen that Fe (iron) is selectively precipitated and removed when the leachate has a pH of 4 to 6. Although not shown, manganese and zinc hardly precipitate in this pH range, and zinc was slightly precipitated and removed at pH: 6, but the amount was as small as about 100 to 200 mg / L. When the pH is 5 or 6, the removal of iron precipitates progresses remarkably, and the iron concentration is reduced to below 0.5 mg / L. As described above, it was found that the iron concentration can be significantly reduced only by applying air aeration, which is an inexpensive oxidation treatment, to the leachate.

Next, the leachate adjusted to pH: 5 was subjected to air aeration (oxidation treatment) to reduce the iron concentration to less than 0.5 mg / L, and then the iron separation step by solid-liquid separation was performed to obtain the first solution. Further, a sulfide precipitation treatment step was performed 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
pH adjuster: 3M sulfuric acid or 100g / L sodium hydroxide Treatment time: 0.5 hours after addition of sodium hydrosulfide (stirring treatment)
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 the ICP emission analysis method.

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 amount of sulfide added was 3 equivalents (NaHS: 3 equivalents), the removal of manganese precipitates tended to increase when the pH was about 5.

Regarding the experiment (B), as described above, manganese obtained by heat-treating the powder or granules of the waste dry battery and then mixing the heat-treated powder or granule with an acid solution or a reducing agent. If the leachate from which zinc and iron have been leached is first subjected to an oxidation treatment, a solution in which most of the iron components are precipitated and separated and removed can be obtained by simply performing a simple oxidation treatment called air aeration (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 below the analysis limit (zinc removal step).

As described above, according to the experiments (A) and (B), iron is subjected to the zinc removing step and the iron removing step in addition to the heat treatment step, regardless of the step sequence of the zinc removing step and the iron removing step. It was found that a high-purity manganese-containing solution in which both iron and iron were reliably precipitated, separated and removed 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.
A heat treatment step in which the powder or granular material obtained in the crushing / sieving step is heat-treated in a non-oxidizing atmosphere, and a heat treatment step.
An acid solution or a reducing agent is mixed with the powder or granular material subjected to the heat treatment step, 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 leaching step to obtain a leachate containing 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 cell, which comprises obtaining a high-purity manganese-containing solution 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 removal 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 and manganese ions and zinc ions 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 (5), 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 heat treatment in the heat treatment step is a treatment for heating to a temperature in the range of 800 ° C. or higher and 1200 ° C. or lower, from a waste dry battery. Manganese recovery method.

(9) In any of (1) to (8), in the heat treatment step, the carbon material is further added to the powder or granular material in a mass ratio of 0.5 or less with respect to the total amount of the powder or granular material. A characteristic method for recovering manganese from waste batteries.

(10) In any of (1) to (9), 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.

(11) In any of (1) to (10), 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.

(12) In any of (1) to (11), 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.

(13) In any of (1) to (12), 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.

(14) A sorting device for sorting 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.
A heating device that heat-treats the powder or granular material obtained by the sieving device in a non-oxidizing atmosphere, and a heating device.
An acid solution or a reducing agent is mixed with the powder or granular material heat-treated by the heating device to leach manganese, zinc and iron contained in the powder or granular material from the powder or granular material to cause manganese ions. , An acid leaching tank 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 by the solid-liquid separator 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 from waste batteries by including 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. , It can be collected at low cost, and it is extremely effective in 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. It is a graph which shows the influence of the graphite compounding ratio as a reducing agent on the zinc removal rate from the powder or granular material in a heat treatment step. It is a graph which shows the influence of the amount of H ₂ O ₂ added as a reducing agent on the manganese leaching rate from the heat-treated powder granules to the leachate in the acid leaching step. It is an X-ray diffraction pattern of the powder or granular material after a heat treatment step. 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 manganese component as a high-purity manganese-containing solution from the waste dry cell. The present invention relates to a method for recovering manganese and a recovery facility for 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 method for recovering manganese of the present invention includes a sorting step, a crushing / sieving step, a heat treatment 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 reliably 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.

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 cell may be selected, only the alkaline manganese dry cell may be selected, or both the manganese dry cell and the alkaline manganese dry cell 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, zinc and carbon 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 solids and powders such as packaging materials constituting a dry battery 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.

Heat treatment step As a heat treatment step, the powder or granular material obtained through the crushing / sieving step is heat-treated in a non-oxidizing atmosphere such as an inert atmosphere or a reducing atmosphere. Zinc (Zn) in the powder or granular material mainly exists as ZnO, and by heat treatment, the graphite in the powder or granular material reacts with ZnO and is reduced from ZnO to zinc (Zn). When the heat treatment is performed in an oxidizing atmosphere, the graphite in the powder or granules or a part of the graphite mixed as a reducing agent reacts with oxygen in the atmosphere and burns instead of ZnO, so from ZnO to zinc. The reduction reaction of zinc oxide is inhibited, and the removal rate of zinc from the powder or granular material is lowered. Therefore, the heat treatment is performed in a non-oxidizing atmosphere, and may be performed in an inert atmosphere or a reducing atmosphere.

In the heat treatment, it is preferable to heat the powder or granular material to 800 ° C. or higher, more preferably to 850 ° C. or higher, further preferably to 900 ° C. or higher, and more preferably 1200 ° C. or lower. It is preferable to heat to a temperature in the range of 800 ° C. or higher and 1200 ° C. or lower. When the temperature of the heat treatment is 800 ° C. or higher, zinc starts to volatilize substantially and becomes zinc vapor and is removed from the powder or granular material. On the other hand, if the temperature of the heat treatment exceeds 1200 ° C., the heating furnace that can be used is limited. From such a viewpoint, it is preferable that the heat treatment is a treatment of heating to a temperature within the above-mentioned suitable range.

Further, in the heat treatment, the reduction reaction from ZnO to zinc can be caused only by the graphite in the powder or granular material. However, in order to increase the efficiency of the zinc reduction reaction, it is preferable to add a non-metal carbon material such as graphite as a reducing agent to the powder or granular material. When blending a carbon material, adjust the mass ratio of the carbon material to the total amount of the powder or granular material (carbon material blending ratio = carbon material / powder or granular material) to 0.5 or less, more preferably 0.01 to 0.5. It is preferable to add it, and it is more preferable to add it in an amount of about 0.1. Since the bulk density of the carbon material is smaller than that of the powder or granular material, if a large amount of carbon material with a carbon material mixing ratio of more than 0.5 is mixed, a large heating facility is required, which is economically disadvantageous. be.
If a metal-based reducing agent is used, the unreacted reducing agent may dissolve in the acid used in the subsequent step, which may deteriorate the quality of the manganese-containing solution. Therefore, the reducing agent used is a non-metal-based reducing agent. It is preferable to use a carbon material.

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

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 in 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 hydrochloric acid concentration of 1% or more and 14% or less in terms of mass% concentration. 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 concentration required for leaching the manganese component, iron component and residual zinc component is 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 in the granules, the morphology of manganese and zinc in the granular material, and the like. Therefore, it is preferable to determine the optimum acid concentration by conducting a preliminary experiment assuming an actual machine in advance.

In the acid leaching step of the present invention, an acid solution or a reducing agent is mixed with the powder or granular material that has undergone the heat treatment step. If the acid alone does not leached sufficiently, a reducing agent is further added as needed to almost completely leached the manganese component contained in the powder or granular material. Most of the manganese contained in the heat-treated granules is MnO, but a small amount of MnO ₂ , Mn ₂ O ₃ , Mn ₃ O ₄ , etc. may be contained. Of these, only a part of Mn O and Mn ₃ O ₄ dissolves only with 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 1 to 500 g / L with respect to the acid solution is sufficient.

As the reducing agent, any of various commonly used reducing agents can be applied. 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 thiosulfate Na ₂ S ₂ O ₃ , and iron sulfate FeSO ₄・ 7H ₂ O. .. 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, if the concentration of the acid is increased regardless of the presence or absence of the reducing agent, almost all of the zinc component is dissolved (leached).

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. Is 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. By heating, the reaction efficiency can be expected to improve as the temperature is raised within the range where the treatment solution does not boil. 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, iron ions, and residual zinc ions. On the other hand, the leachate 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), a sulfide precipitation treatment step is first applied to the solid-liquid separated leachate. In this sulfide precipitation treatment step, sulfide is allowed to act on the leachate, and the zinc ions mainly remaining among the ions contained in the leachate are precipitated as zinc sulfide so that they can be removed from the leachate. 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 ions, iron ions, and residual zinc ions. When sulfide acts on the leachate, the divalent metal ions contained are sulfide ions S. Reacts with ^2- to form sulfide and precipitate. 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).

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, it is possible to suppress the precipitation of unintended manganese ions and prevent the amount of sulfide acting to be excessive, which is economically disadvantageous.

In addition, if the pH of the leachate when the sulfide is allowed to act is too low, less than 2, zinc precipitation will be insufficient, while if it is higher than 5, the amount of manganese precipitation will increase and the amount of manganese that can be recovered will decrease. However, manganese loss progresses and manganese yield decreases. From such a viewpoint, the pH of the leachate in the sulfide precipitation treatment step is preferably 2 or more, more preferably 3 or more, preferably 6 or less, more preferably 5 or less, still more preferably less than 5. The pH of the leachate is preferably pH 2 or more and 5 or less, more preferably pH 3 or more and 5 or less, and even more preferably pH 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 and the zinc-containing precipitate in which the residual zinc sulfide is mainly precipitated are separated. As a result, the zinc component can be easily separated from the mixture after the sulfide precipitation treatment step, and a first solution containing manganese ions and iron ions can be obtained. The separation means is not particularly limited, and the solid-liquid separation step described above may be followed.
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.

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 containing the manganese ion and the iron ion obtained in the previous zinc removal step is subjected to an oxidation treatment step, and the iron ion in the first solution is subjected to an iron-containing precipitate. As a product, iron components can also be separated and removed. 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, if 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 separated and removed. This is because the sulfide added in the sulfide precipitation treatment step acts as a reducing agent in this step. It is considered that this reducing agent consumes oxygen supplied by air aeration, the amount of oxygen is insufficient depending on the amount of air aeration, and iron content that cannot be separated and removed remains in the treated solution. If air aeration is continued, the sulfide becomes sulfate ion, and finally the solution becomes oxidative and the iron component also precipitates. However, the aeration time becomes long and it 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 to stand for an appropriate period, and then the oxidation treatment step is performed, the iron component can be sufficiently precipitated by the treatment of only 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 period here depends 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. In addition, as finish oxidation, a process of adding an oxidizing agent may be added.

The oxidation treatment is preferably performed by adjusting the pH of the leachate with a pH adjuster. If the pH of the leachate is less than 3 and too low, the iron component will not precipitate. On the other hand, if the pH of the leachate exceeds 7 and 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, 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 mixed with a first solution containing manganese ions and zinc ions, and an iron-containing precipitate containing mainly 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), 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 and remain. The 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.
The type of sulfide and the suitable pH of the first solution may be determined according to the sulfide precipitation treatment method in the above-mentioned procedure (A). The pH of the first solution is particularly preferably pH: 4.
The amount of sulfide to act is preferably 1.1 equivalents or more, more preferably 2 equivalents or more, and preferably 5 equivalents or less as sulfur S with respect to dissolved zinc. If the amount of sulfide to act is less than 1.1 equivalents, zinc precipitation removal is progressing but incomplete, and the final removal rate is not stable. When the amount of sulfide to act is 2 equivalents or more, the removal of zinc precipitate is also remarkable. Further, when the amount of sulfide to be acted on exceeds 5 equivalents, the amount of sulfide to be acted upon becomes excessive, and manganese may also be precipitated and removed.

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 in which zinc sulfide is mainly precipitated (zinc separation). Step), remove the zinc component. In this way, the remaining zinc component can also be removed, and the solution can be recovered as a high-purity solution containing only the manganese component.
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 manganese contained in the waste dry battery can be removed from the zinc component and iron component. It can be recovered with a high yield as a high-purity manganese-containing solution reduced to less than the analysis limit.
The obtained manganese-containing solution may be alkaline-precipitated and used as a high-purity manganese hydroxide for various purposes. Further, the obtained manganese-containing solution may be mixed with other metals such as Ni and then subjected to an alkali precipitation treatment or the like to be used as a 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 is provided in order with a sorting device, a crushing device, a sieving device, a heating device, an acid leaching tank, a solid-liquid separation device, and a manganese extraction device group, and has the same features and effects as the manganese recovery method of the present invention. Have. 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. 9 shows a configuration (A) in which the above procedure (A) can be suitably carried out. As schematically shown in FIG. 9, the recovery equipment includes a sorting device 10, a crushing device 20a, a sieving device 20b, a heating device 110, an acid leaching tank 30, a solid-liquid separation device 40, and sulfide. The 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 heating device 110 is a device capable of heat-treating the powder or granular material obtained through the crushing device 20a and the sieving device 20b to a set temperature in a non-oxidizing atmosphere having an inert atmosphere or a reducing atmosphere. The structure is not particularly limited. If the heating device is a batch type, a heating furnace capable of adjusting the normal atmosphere is suitable. Further, if the heating device is a continuous type, a rotary kiln or the like that can heat to a set temperature and adjust the atmosphere is suitable. The atmosphere adjustment referred to here also includes a means for collecting exhaust gas containing zinc vapor.

The acid leaching tank 30 is preferably a general stirring tank equipped with a stirrer in the tank because the powder or granular material is mixed with an acid solution or a reducing agent 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. 10 shows a configuration (B) in which the above procedure (B) can be suitably carried out. As schematically shown in FIG. 10, the recovery equipment includes a sorting device 10, a crushing device 20a, a sieving device 20b, a heating device 110, an acid leaching tank 30, a solution separation device 40, and an oxidation treatment. A tank 53, an iron separation device 63, a sulfide precipitation treatment tank 83, a zinc separation device 93, and a 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, the sorting device 10, the crushing device 20a, the sieving device 20b, the heating device 110, the acid leaching tank 30, the solid-liquid separation device 40, the iron separation device 63, the zinc separation device 93, the recovery tank 70a, 73b, 73c, and manganese. The contained solution recovery tank 100 is as described above for the configuration A.
In the oxidation treatment tank 53, since the leachate is subjected to the oxidation treatment, 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 powder and granules The process of sorting manganese dry batteries and alkaline manganese dry batteries from waste dry batteries, and crushing and sieving the selected waste dry batteries with a sieve with a mesh size of 2.8 mm to obtain powder and granules of waste dry batteries. The division step was performed to obtain powders and granules of waste dry batteries. The composition of the obtained powder or granular material is shown in Table 1. The obtained powder or granular material contains oxygen, some hydrogen and water derived from an oxide or a hydroxide in addition to the elements shown in Table 1.

Preparation of Leachate A heat treatment step was performed in which the obtained powder or granular material was charged into the heating device 110 and subjected to heat treatment without adding graphite. The heat treatment was performed in an inert atmosphere, N ₂ atmosphere, with a heating temperature of 1000 ° C. and a heating time of 1 hour.
The powder or granular material obtained through the heat treatment step was put into the acid leaching tank 30 and subjected to the acid leaching step. In the acid leaching step, 100 mL of an acid solution was mixed with 10 g of the powder or granular material, and an acid leaching treatment was performed to leach manganese, zinc and iron from the powder or granular material. The acid concentration of the acid solution was sulfuric acid concentration: 3N (mass% concentration: about 13.2%). 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 100 g / L.

After the acid leaching treatment, the obtained leachate and the leachate residue were charged into the solid-liquid separation device 40, filtered through a filter paper having a pore size of 1 μm, and subjected to a solid-liquid separation step. The manganese concentration, zinc concentration, and iron concentration in the obtained leachate were quantified by ICP emission spectrometry. Table 2 shows the concentrations (mg / L) of each component of manganese, zinc, and iron in the leachate after the solid-liquid separation step.
The manganese mass in the leachate was calculated based on the manganese concentration in the obtained leachate, and the ratio of the manganese mass in the leachate to the manganese mass in the powder or granules after the heat treatment, which was separately measured (manganese). (Element conversion) was calculated and used as the manganese leaching rate. The manganese leaching rate was 100%.

Preparation of first solution (zinc removal step)
Next, the leachate obtained by the solid-liquid separation step was charged into the sulfide precipitation treatment tank 52, and a sulfide precipitation treatment step of allowing sulfide to act was performed. In the sulfide precipitation treatment step, sodium hydrosulfide NaHS as a sulfide was added to the leachate so as to have 2 equivalents of sulfur S with respect 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 step described above is charged into a zinc separation device 62, and a zinc separation step of suction filtration with a filter paper having a pore size of 1 μm for solid-liquid separation is performed to separate the first solution and the zinc-containing precipitate. did. Then, the components of the obtained first solution 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 charged into the oxidation treatment tank 82, and an oxidation treatment step of performing an oxidation reaction was performed. 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 amount of blown water: (the same volume as the amount of the first solution) / minute, and the 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 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. About 8 to 16 mL 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.

The iron separation step of charging the mixture after the oxidation treatment step by air aeration and addition of an oxidizing agent into the iron separation device 92, suction-filtering it with a filter paper having a pore size of 1 μm, and solid-liquid separation into the second solution and the iron-containing precipitate. provided.
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 procedure A of the manganese recovery method of the present invention, zinc components and iron components 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 95.4%. 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 100%.

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 solution obtained through the second solid-liquid separation step was left at room temperature for one week, and then charged into the oxidation treatment tank 82 to carry out an oxidation treatment step. In the oxidation treatment step, the first solution obtained as the oxidation treatment was aerated with air. 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 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 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 100%.

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: (same volume as the amount of exudate mL) / min, 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 96.0%.
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 Sorting device 20a Crushing device 20b Sieving device 30 Acid leaching tank 40 Solid-liquid separation device 52 Sulfide precipitation treatment tank (Structure 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 110 Heating device

Claims (14)

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.
A heat treatment step of subjecting the powder or granular material obtained in the crushing / sieving step to a heat treatment in a non-oxidizing atmosphere at a temperature of 850 ° C. or higher .
An acid solution or a reducing agent is mixed with the powder or granular material subjected to the heat treatment step, 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 leaching step to obtain a leachate containing 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 cell, which comprises obtaining a high-purity manganese-containing solution in no particular order. 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 method for recovering manganese from a waste dry cell according to claim 2, wherein in the sulfide precipitation treatment step, the leachate is adjusted to have a pH of 2 or more and 6 or less. 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: 3. 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 removal 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 and manganese ions and zinc ions 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 have a pH of 2 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 3 or more and 7 or less. .. The method for recovering manganese from a waste dry cell according to any one of claims 1 to 7, wherein the heat treatment in the heat treatment step is a treatment of heating to a temperature in the range of 1200 ° C. or lower. The invention according to any one of claims 1 to 8, wherein in the heat treatment step, a carbon material is further added to the powder or granular material in a mass ratio of 0.5 or less with respect to the total amount of the powder or granular material. The method for recovering manganese from the described waste dry cell. Any of claims 1 to 9, 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 10, 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 11. The method for recovering manganese from the described waste dry battery. The waste dry battery according to any one of claims 1 to 12, 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.
A heating device that heat-treats the powder or granular material obtained by the sieving device in a non-oxidizing atmosphere, and a heating device.
An acid solution or a reducing agent is mixed with the powder or granular material heat-treated by the heating device to leach manganese, zinc and iron contained in the powder or granular material from the powder or granular material to cause manganese ions. , An acid leaching tank 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 by the solid-liquid separator 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 from waste batteries by including them in no particular order.

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