JPH0361730B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is a method for completely recovering valuable materials from waste manganese dry batteries.The purpose of the present invention is to separate and recover valuable materials in manganese dry batteries, solve the pollution problem associated with disposal, and completely recover valuable materials from waste manganese dry batteries. The objective is to provide a method that can contribute to resource saving measures through collection. In recent years, with the development of electric appliances such as portable radios and portable tape recorders, and various electric toys, the number of dry batteries used has reached an enormous amount, and the number of waste manganese dry batteries being disposed of is increasing year by year. Therefore, the discarded manganese dry batteries are
It contains various valuable substances such as iron, zinc, manganese, mercury, cadmium, and graphite, which is not desirable in terms of resource conservation measures. For this reason, a few methods have been proposed for recovering valuable materials from waste manganese dry batteries (Japanese Patent Application Laid-Open No. 1989-
Publication No. 1094, Publication No. 51-69261). However, all of the above-mentioned methods have the main purpose of recovering manganese, zinc, manganese, zinc, iron, etc., and recovery of other Hg, Cd, etc. is not necessarily sufficient. As a result of further research on the above-mentioned conventional method, the present inventors were able to obtain a method for completely recovering various valuable materials in waste manganese dry batteries by adopting the configuration described in the claims. That is, the present invention crushes waste manganese dry batteries to the extent that their airtightness is destroyed and heats them to 400 to 600°C in a metal vapor condenser additional heating furnace to melt and recover zinc, while at the same time recovering iron, manganese, graphite, etc. The first step is to collect the metal vapor or metal compound vapor generated by heating as a solid substance, and the solid substance recovered in the first step is heated to 700°C in a reducing atmosphere.
It is characterized by the following steps: heating to ~1100°C, cooling, separating and recovering iron by magnetic separation, adding an aqueous sulfuric acid solution to dissolve and extracting manganese, and then over-separating graphite. This is a method for completely recovering valuable materials from waste manganese dry batteries. To further explain the present invention in detail, in the first step, a waste manganese dry battery (hereinafter referred to as a dry battery) is crushed to the extent that its airtightness is destroyed. That is, the crushing prevents the dry battery from exploding during heat treatment, and
This is to promote the dissolution of the Zn can inside the battery and the evaporation of Hg, Cd, and other metal vapors. It is enough to crush it.
Therefore, subsequent separation of solid matter is easy. After the above-mentioned crushing treatment, the dry battery is heated at 400 to 600° C. for about 1 to 6 hours in a metal vapor condenser additional heating furnace. The heating furnace is advantageously an electric furnace such as a low frequency furnace or a high frequency furnace, but the heating method is not necessarily limited to the electric furnace. Through the heat treatment in the heating furnace, the Zn can is melted to form a molten phase, and metals with low vapor pressure such as Hg and Cd or metal compounds such as HgCl and ZnCl ₂ are evaporated to form a gas phase. do. On the other hand, solid phases such as Fe and Mn contained in dry batteries do not melt during the heat treatment and remain in a solid phase.
Since it is taken out, it can be easily separated. In addition, in order to separate the molten phase of zinc from the solid phase of Fe, Mn, graphite, etc., either tap only the molten phase after heating in a heating furnace to separate it, or separate the molten phase and solid phase from the heating furnace. It can be easily separated by tapping the two at the same time and collecting the molten phase in a ladle equipped with a partition plate. Further, various organic polymers contained in the dry cell are decomposed and carbonized by the heat treatment, and the decomposed gas can be cooled and collected by a condenser, so that contamination by these decomposed gases can be avoided. Metals such as Hg and Cd and compounds (including a small amount of ZnCl ₂ ) obtained by the above heat treatment are cooled and solidified, dissolved in hydrochloric acid, and then PH-treated with NH ₄ OH as appropriate.
Adjustments were made, and Hg was replaced with a chelate resin for mercury adsorption.
In addition, Cd (including some Zn and Pb) is recovered separately using chelate resin or ion exchange resin, and then
The liquid is concentrated and collected as a NH ₄ Cl solution. still,
If necessary, the Hg vapor may be recovered as Hg-Al amalgam by reacting with metal aluminum. On the other hand, the molten phase of Z _o still contains trace amounts of Fe, Mn, Pb,
This is crude zinc containing metals such as Cd. After dissolving it in hydrochloric acid, it is oxidized to oxidize and over-separate Fe, Mn, etc., and is purified and recovered as a zinc chloride solution with a concentration of 50%. In addition, when Cd and Pb are included in this molten phase, Fe, Mn, etc. can be removed by oxidation, further separated, and recovered by dissolving in hydrochloric acid together with the metal vapor in the gas phase. Next, the Fe separated and recovered in the first step,
The solid material containing Mn, graphite, and zinc and zinc compounds that could not be separated in the first step is heat-treated at 700 to 1100° C. for 1 to 6 hours as a second step. In this heat treatment, graphite is contained in the solid,
A reducing atmosphere is formed by heating, so that the first
Once oxidized in the process, Mn ₂ O ₃ becomes easily soluble in sulfuric acid.
It has the advantage that it is reduced to MnO and that the contained zinc and zinc compounds can be recovered free of impurities. Next, this is once separated into iron and other compounds using a vibrating sieve, etc., and after the iron is separated by magnetic separation, dilute sulfuric acid is added to this to extract MnO as MnSO ₄ and further contain. After over-separating the graphite, it is suitably neutralized with Ca(OH) ₂ etc., and if necessary, impurities are over-separated and recovered as a manganese sulfate solution. Further, the zinc recovered by the spool may be recovered as is or may be sent to the molten phase recovery step in the first step and recovered. That is, in the present invention, after crushing a dry battery, Hg, Cd, etc. with low vapor pressure are recovered as metal vapor through heat treatment in the first step, and also recovered as a molten phase of Zn, and the Zn is dissolved in hydrochloric acid. In addition to recovering zinc chloride, solids such as Fe and Mn contained in the molten phase are oxidized and separated, and in a second step, Fe is removed and separated from the oxidized and separated solids,
By dissolving Mn in sulfuric acid, extracting it, and recovering it as an aqueous manganese sulfate solution, it is possible to recover not only Fe, Zn, and Mn contained in dry batteries, but also valuable metals such as Hg and Cd, thus saving money. Not only can it contribute to resources, but also by recovering Hg, Cd, etc.
A so-called closed system can be formed and pollution problems can be completely eliminated. The drawing shows one embodiment of the present invention, and as is clear from this flow sheet, Hg, Cd can be removed by crushing and heating a dry battery.
Metals such as HgCl, ZnCl ₂ and other compounds with low vapor pressure can be recovered in the gas phase, while Zn
can be recovered as a molten phase, and after removing Fe and Mn mixed in the molten phase as oxides,
It can be recovered as _ZnCl2 . In addition, solid phases such as iron, manganese oxide, graphite, and unmolten zinc or zinc compounds are removed by evaporation of zinc by heating, then separated by magnetic separation to remove iron, and then the manganese is removed by sulfuric acid. By extracting and recovering as a manganese sulfate solution, many valuable substances in dry batteries can be almost completely separated and recovered. In addition, some of the materials recovered by the present invention can be reused as chemicals, and the manganese sulfate solution can be reused as an electrolyte during the production of electrolytic manganese dioxide, which is an effective resource saving measure. It is. In addition, as is clear from the drawings, the present invention has Fe,
It is a so-called closed system that can not only recover Mn, Zn, graphite, etc., but also effectively recover Hg, Cd, etc., which cause pollution problems in dry batteries, so there is no risk of causing pollution problems. The present invention will be explained below with reference to Examples. Example 20 used UM-type manganese dioxide batteries
After the pieces were crushed and deformed using a crusher, they were placed in a quartz crucible and heated at 500°C for 3 hours in a 20KVA high frequency furnace equipped with a metal vapor condenser. The metal vaporized by the heating is cooled and collected in a metal vapor condenser having a water seal holder,
After dissolving in hydrochloric acid and adjusting the pH to 1 to 2 with aqueous ammonia, adsorbing mercury on a mercury adsorption resin, and adjusting the pH to 7 with aqueous ammonia, adsorbing Cd, Zn, and Pd with a chelate resin. to recover. Further, the liquid was concentrated and then recovered as an aqueous ammonia chloride solution. Further, after separating the melt obtained from the high frequency furnace and the solid, the melt is dissolved in dilute hydrochloric acid, hydrogen peroxide is added and oxidized, and the precipitate is mixed with the solid. The liquid is further purified by adding zinc powder, concentrated, and recovered as a 50% zinc chloride aqueous solution. On the other hand, the solid material is again put into the high frequency furnace, sealed and heated at 1000° C. for 3 hours. At this time, the evaporating zinc vapor is cooled and collected in a condenser. After the heat treatment, iron is recovered using a magnetic separator, dilute sulfuric acid is added to the residue, manganese is dissolved and extracted as manganese sulfate, graphite is recovered by filtration, and impurities are removed after neutralization with calcium carbonate. to recover the manganese sulfate solution. The weight composition of the valuable materials in the waste manganese dry batteries mentioned above is shown in Table 1, and the total recovery rate of each valuable material is shown in Table 2.
Shown in the table.

【table】

[Table] Furthermore, Hg and Cd could be almost completely recovered using adsorbents, and could be treated in a closed system without being disposed of outside the reaction system.

[Brief explanation of drawings]

The drawing is a flow sheet of one embodiment of the present invention.

Claims (1)

[Claims] 1 Crush waste manganese dry batteries to the extent that their airtightness is destroyed, and heat them in a metal vapor condenser heating furnace for 400~
a first step of heating to 600°C to melt and recover zinc, and at the same time recovering iron, manganese, graphite, etc. as solid substances; on the other hand, recovering metal vapor or metal compound vapor generated by heating; The solids recovered in the process are heated to 700 to 1100℃ in a reducing atmosphere, cooled, and then iron is separated and recovered by magnetic separation. A sulfuric acid aqueous solution is added to this to dissolve and extract manganese, and graphite is overseparated. A method for completely recovering valuables from waste manganese dry batteries.