阅读说明：本技术 一种废旧锌锰电池的回收再利用方法 (Recycling method of waste zinc-manganese battery ) 是由 雷立旭 冀帅 张天择 于 2019-09-16 设计创作，主要内容包括：本发明公开了一种废旧锌锰电池的回收再利用方法,包含以下步骤：(1)将废旧电池投入分选机,得到规格不同的锌锰电池；(2)将它们分别破壳、磁选、筛分,得到电池粉；(3)向电池粉加水使电解质全部溶解,过滤得到电解质溶液,然后蒸发浓缩、分级结晶得到纯的氨水、KCl和KOH；(4)向所得固体加水、稀硫酸和还原剂,搅拌反应得到硫酸锌和硫酸锰的混合溶液；(5)混合溶液加步骤(2)所得锌皮除杂,滤去固体后直接电解,在阳极得到二氧化锰,在阴极得到锌；(6)将所得的锌和二氧化锰用于制造新的碱性锌锰电池。本发明可以使废旧锌锰电池中的材料100％资源化,使锌锰电池得到循环生产,能耗、物耗、污染风险大大减少。(The invention discloses a recycling method of waste zinc-manganese batteries, which comprises the following steps: (1) Putting the waste batteries into a sorting machine to obtain zinc-manganese batteries with different specifications; (2) Breaking shells, magnetically separating and screening the materials to obtain battery powder; (3) Adding water into the battery powder to completely dissolve the electrolyte, filtering to obtain an electrolyte solution, and then evaporating, concentrating and performing fractional crystallization to obtain pure ammonia water, KCl and KOH; (4) Adding water, dilute sulfuric acid and a reducing agent into the obtained solid, and stirring to react to obtain a mixed solution of zinc sulfate and manganese sulfate; (5) Adding the zinc skin obtained in the step (2) into the mixed solution to remove impurities, filtering out solids, and then directly electrolyzing to obtain manganese dioxide at the anode and zinc at the cathode; (6) The resulting zinc and manganese dioxide are used to make new alkaline zinc-manganese batteries. The invention can recycle 100% of materials in the waste zinc-manganese batteries, so that the zinc-manganese batteries are circularly produced, and the energy consumption, material consumption and pollution risks are greatly reduced.)

1. A method for recycling waste zinc-manganese batteries is characterized by comprising the following steps:

(1) Putting the waste batteries into a sorting machine, and sorting according to the size, shape, weight and magnetism of the batteries to obtain zinc-manganese batteries, nickel-hydrogen batteries, nickel-cadmium batteries and lithium ion batteries with different specifications;

(2) Respectively crushing shells of zinc-manganese batteries with different specifications, separating iron sheets by using a magnetic separation technology, screening and classifying zinc skins, carbon rods, diaphragms, steel nails, battery powder and organic matters for insulating positive and negative electrodes and sealing the batteries, respectively cleaning other parts except the battery powder, and using the obtained cleaning solution containing the battery powder for next step of extracting electrolyte;

(3) Mixing the battery powder with the solid and liquid obtained in the last step, adding water for several times to dissolve and elute the electrolyte in the battery powder, and performing solid-liquid separation to obtain a solution of the electrolyte and the battery powder without the electrolyte; evaporating, concentrating and carrying out fractional crystallization on the electrolyte solution to obtain an electrolyte;

(4) Adding dilute sulfuric acid and a reducing agent into the battery powder without the electrolyte obtained in the step (3), stirring to ensure that all manganese compounds in the battery powder are converted into manganese sulfate and all zinc compounds are converted into zinc sulfate, and filtering and separating to obtain a mixed solution of zinc sulfate and manganese sulfate and insoluble substances;

(5) Adding the zinc skin obtained in the step (2) into the mixed solution of zinc sulfate and manganese sulfate obtained in the step (4), stirring to remove impurity ions, and filtering to obtain a solution only containing zinc sulfate and manganese sulfate;

(6) Electrolyzing the solution of zinc and manganese sulfate obtained in the step (5) to obtain electrolytic manganese dioxide at the anode and zinc at the cathode;

(7) The resulting zinc and electrolytic manganese dioxide are used to make new alkaline zinc-manganese batteries.

2. The recycling method of the waste zinc-manganese dioxide battery according to claim 1, characterized in that: the waste zinc-manganese battery comprises an acid zinc-manganese battery and an alkaline zinc-manganese battery.

3. The recycling method of the waste zinc-manganese dioxide batteries according to claim 1, characterized in that: the reducing agent in the step (4) is a substance which can react with Mn (IV) or Mn (III) compounds in a sulfuric acid medium to obtain Mn (II) compounds.

4. The recycling method of the waste zinc-manganese dioxide battery according to claim 3, characterized in that: the reducing agent is a substance whose oxidation product is a harmless gas, including H ₂ O ₂ Any one of formic acid, formaldehyde, methanol, oxalic acid, hydrazine and hydroxylamine.

5. The recycling method of the waste zinc-manganese dioxide batteries according to claim 1, characterized in that: the temperature at which the reduction reaction in the step (4) occurs is room temperature to 180 ℃.

6. The recycling method of the waste zinc-manganese dioxide battery according to claim 5, characterized in that: the reduction reaction in the step (4) is carried out in a pressure vessel at a temperature of 100-180 ℃.

7. The recycling method of the waste zinc-manganese dioxide battery according to claim 1, characterized in that: the electrolysis temperature in the step (6) is 15-80 ℃.

8. The recycling method of the waste zinc-manganese dioxide battery according to claim 7, characterized in that: the pH value of the mixed solution is between 0 and 5, the cell voltage is controlled to be between 2.0 and 2.5V, and the current density is between 40 and 200A/m ² 。

9. The recycling method of the waste zinc-manganese dioxide battery according to claim 7, characterized in that: when the pH value of the mixed solution is more than 5, dilute sulfuric acid is added to reduce the pH value to 5.

10. The recycling method of the waste zinc-manganese dioxide battery according to claim 7, characterized in that: and (3) when the pH value of the mixed solution is less than 0, stopping electrolysis, and replacing sulfuric acid in the step (4) with the formed electrolyte solution for recycling.

Technical Field

The invention relates to the recycling production of batteries, in particular to a recycling method of waste zinc-manganese batteries.

Background

The zinc-manganese cell is a common primary cell which can be stored for a long time, is widely used as a power supply of low-power electric appliances, such as various electronic clocks, stove ignition power supplies, emergency reserve power supplies and the like, and can be stored for years without deterioration. Generally, zinc-manganese batteries can be divided into two categories: the acid zinc-manganese battery (also called carbon battery in the market) which is extremely cheap and the alkaline zinc-manganese battery which is more expensive but has much larger electricity storage capacity and much better power characteristics.

The acid zinc-manganese battery uses a carbon rod as a positive current collector. Around the carbon rod is surrounded by electrochemically active MnO ₂ The paste formed by mineral powder, graphite powder and ammonium chloride aqueous solution forms the positive electrode of the battery, the positive electrode and a metal zinc cylinder used as the negative electrode are separated by a diaphragm, and an organic material which separates the positive electrode from the negative electrode and seals the battery is added, so that the acid (or carbon) zinc-manganese dry battery is formed. Thus, the acid zinc-manganese battery contains carbon rods and MnO ₂ The device comprises a zinc cylinder, an iron sheet shell, graphite powder, ammonium chloride and a paper diaphragm. The alkaline zinc-manganese dioxide battery is different from the alkaline zinc-manganese dioxide battery in structure, a negative electrode formed by zinc powder and a steel needle is arranged in the middle, electrolytic manganese dioxide and an iron bucket are used as positive electrodes and arranged outside, and KOH aqueous solution is used as electrolyte. Therefore, the alkaline zinc-manganese battery contains zinc, a steel needle, an iron shell and MnO ₂ And an alkaline solution. In the waste battery, most of the metal zinc is changed into divalent zinc compound MnO ₂ Most of them become trivalent manganese compounds.

The zinc-manganese battery has a disadvantage of being disposable, and thus, although the purchase cost is low, the use cost is higher than that of the secondary battery. At present, metals with higher toxicity, such as mercury, cadmium and the like, are not used in the zinc-manganese battery, and the environmental friendliness degree is greatly improved. However, zinc-manganese batteries contain valuable elements of zinc, manganese and iron, which cause certain environmental hazards when directly entering the environment, and more importantly, the valuable elements of zinc, manganese and iron cause waste of valuable metal resources.

At present, some zinc-manganese battery recycling technical schemes exist. For example, chinese patent No. 201210496512.2 discloses a method for treating waste zinc-manganese batteries, which comprises the steps of crushing, dissolving and filtering the batteries to obtain a solution of zinc-manganese salt, then gradually electrodepositing metallic zinc and manganese dioxide, and then extracting heavy metals such as cadmium, copper, lead and the like through ion exchange. The existing zinc-manganese battery recovery treatment mainly aims at zinc oxide, and the resource utilization rate is generally low.

Disclosure of Invention

The purpose of the invention is as follows: in order to overcome the defects in the prior art, the invention aims to provide a method for recycling waste zinc-manganese batteries, which can obviously reduce energy consumption, material consumption and pollution risk and can realize the cyclic production of the zinc-manganese batteries.

The technical scheme is as follows: the invention relates to a method for recycling waste zinc-manganese batteries, which comprises the following steps:

(1) Putting the waste batteries into a sorting machine, and sorting according to the size, shape, weight and magnetism strength of the batteries to obtain zinc-manganese batteries, nickel-hydrogen batteries, nickel-cadmium batteries and lithium ion batteries with different specifications, wherein part of secondary batteries, such as the nickel-hydrogen batteries, the nickel-cadmium batteries and the lithium ion batteries, have the same shape and size and need to be separated according to the magnetism and the mass;

(2) And (3) placing zinc-manganese batteries with different specifications into a special shell breaking machine for shell breaking by using a mild physical disassembly technology. Because the iron sheet is easy to be attracted by a magnetic field, the iron sheet is separated by using a magnetic separation technology, and the zinc sheet, the carbon rod, the diaphragm, the steel nail and the battery powder are separated, so that organic matters for separating the positive electrode from the negative electrode and sealing the battery are classified by screening. Cleaning other parts except the battery powder, concentrating, selling or using for other purposes, and cleaning the obtained solid-liquid mixture for extracting electrolyte in the next step;

(3) And mixing the battery powder with the solid-liquid mixture obtained in the last step, adding water for several times to dissolve the electrolyte in the mixture, and performing solid-liquid separation to obtain a solution of the electrolyte and the battery powder without the electrolyte. Evaporating, concentrating and performing fractional crystallization on the electrolyte solution by adopting a low-energy-consumption MVR technology to obtain ammonia water, KCl and KOH;

(4) And (4) adding sulfuric acid and a reducing agent into the battery powder without the electrolyte obtained in the step (3), and stirring to convert all manganese compounds into manganese sulfate and all zinc compounds into zinc sulfate. The reducing agent is a substance capable of reacting with Mn (IV) or Mn (III) compound in sulfuric acid medium to obtain Mn (II) compound, and comprises H ₂ O ₂ Any one of formic acid, formaldehyde, methanol, oxalic acid, hydrazine and hydroxylamine; the reduction reaction occurs at a temperature of room temperature to 180 ℃; when the temperature is 100-180 ℃, the reaction is carried out in a pressure vessel. Filtering and separating to obtain a mixed solution of zinc sulfate and manganese sulfate and insoluble substances;

(5) Adding the zinc skin obtained in the step (2) into the mixed solution of zinc sulfate and manganese sulfate obtained in the step (4), stirring to ensure that impurity ions such as iron, lead, cadmium, copper and the like in the mixed solution are all reduced and precipitated to remove impurities, and filtering to obtain a solution only containing zinc sulfate and manganese sulfate;

(6) Electrolyzing the solution of zinc and manganese sulfate obtained in the step (5) to obtain electrolytic manganese dioxide at the anode and zinc at the cathode, wherein the electrolysis temperature is 15-80 ℃;

(7) The resulting zinc and electrolytic manganese dioxide are used to make new alkaline zinc-manganese batteries.

The waste zinc-manganese battery comprises an acid zinc-manganese battery and an alkaline zinc-manganese battery.

In the step (6), the pH value of the mixed solution is controlled to be 0-5, the cell voltage is controlled to be 2.0-2.5V, and the current density is controlled to be 40-200A/m ² (ii) a When the pH value of the mixed solution is more than 5, adding dilute sulfuric acid to reduce the pH value to 5; and (4) when the pH value of the mixed solution is less than 0, stopping electrolysis, and replacing the sulfuric acid in the step (4) with the formed electrolyte solution for recycling.

The working principle is as follows: when the battery is broken, only the battery powder is chemically treated. First, ammonium chloride in an acid cell can react with KOH in an alkaline cell to produce ammonia gas. The reaction formula is as follows:

NH ₄ Cl+KOH＝KCl+NH ₃ +H ₂ O

thus, ammonia is separated and absorbed by water to obtain ammonia water. Thereafter, water was added to the battery powder in portions to wash out all the electrolyte. Evaporating, concentrating and performing fractional crystallization on the electrolyte solution to obtain solid such as KCl, KOH and the like. The obtained ZnO, mnOOH and MnO ₂ Etc. and then reducing the high-valence manganese compound with a reducing agent. In principle, any organic or inorganic reducing agent which can be reacted with Mn (IV) or Mn (III) compounds in a sulphuric acid medium to give Mn (II) compounds can be used, in particular oxidation products which are harmless gases, such as N ₂ 、O ₂ And CO ₂ Substances of, e.g. H ₂ O ₂ Formic acid, formaldehyde, methanol, oxalic acid, hydrazine and hydroxylamine substances. With H ₂ O ₂ For example, the reaction formula is:

MnO ₂ +H ₂ O ₂ +H ₂ SO ₄ ＝MnSO ₄ +O ₂ +2H ₂ O

2MnOOH+H ₂ O ₂ +2H ₂ SO ₄ ＝2MnSO ₄ +O ₂ +4H ₂ O

ZnO+H ₂ SO ₄ ＝ZnSO ₄ +H ₂ O

in this way, all the Zn and Mn compounds in the solid are dissolved to form a mixed salt solution of Zn and Mn. The solution can be purified by reducing and precipitating Fe, cu, etc. in the solution by adding the Zn flake separated previously to the solution:

Zn+Fe ²⁺ ＝Zn ²⁺ +Fe

Zn+Cu ²⁺ ＝Zn ²⁺ +Cu

……

under controlled conditions, the zinc sulfate and manganese sulfate solutions obtained as above are directly electrolyzed to obtain electrolytic manganese dioxide on the anode and metallic zinc on the cathode, which can be used for producing alkaline zinc-manganese batteries. Thus, the aim of manufacturing the high-performance alkaline zinc-manganese dioxide battery by using the waste zinc-manganese dioxide battery is realized:

ZnSO ₄ +MnSO ₄ +2H ₂ O＝Zn+MnO ₂ +2H ₂ SO ₄

it can be seen that only some reducing agents are consumed in the process, only ammonia water, steel nails, carbon rods, iron sheets and the like are byproducts, and all sulfuric acid generated in the electrolysis process is used by the battery powder. Therefore, the process is very clean and has small pollution risk, and is a green process.

Has the beneficial effects that: compared with the prior art, the invention has the following remarkable characteristics:

1. all the components of the battery are recycled, so that the full use of the battery is realized, the recycling rate is high, and the energy consumption, material consumption and pollution risk are greatly reduced;

2. the energy consumption, material consumption and pollution risk in the resource process are reduced to the minimum, and only CO is generated ₂ 、O ₂ 、N ₂ The gas is discharged, and the byproduct is the mixture of ammonia water and solid saline alkali;

3. the production of low-quality acid zinc-manganese batteries can be eliminated step by step, and compounds for producing high-performance zinc-manganese batteries, such as zinc, electrolytic manganese dioxide and the like, can be directly obtained, so that the cyclic production of high-performance alkaline zinc-manganese batteries is realized;

4. the process is simple and easy to implement, redundant processes are avoided, the requirement of clean production is met, the production cost is reduced, and the resource and sustainable production of the waste zinc-manganese battery are facilitated.

Drawings

FIG. 1 is a process flow diagram of the present invention.

Detailed Description