JPH044252B2 - - Google Patents
Info
- Publication number
- JPH044252B2 JPH044252B2 JP61165380A JP16538086A JPH044252B2 JP H044252 B2 JPH044252 B2 JP H044252B2 JP 61165380 A JP61165380 A JP 61165380A JP 16538086 A JP16538086 A JP 16538086A JP H044252 B2 JPH044252 B2 JP H044252B2
- Authority
- JP
- Japan
- Prior art keywords
- emd
- sulfuric acid
- mno
- washed
- present
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 42
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 19
- NUJOXMJBOLGQSY-UHFFFAOYSA-N manganese dioxide Chemical compound O=[Mn]=O NUJOXMJBOLGQSY-UHFFFAOYSA-N 0.000 claims description 12
- AMWRITDGCCNYAT-UHFFFAOYSA-L hydroxy(oxo)manganese;manganese Chemical compound [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 239000008151 electrolyte solution Substances 0.000 claims description 3
- 238000005406 washing Methods 0.000 description 12
- 239000011572 manganese Substances 0.000 description 11
- 150000002500 ions Chemical class 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 238000010298 pulverizing process Methods 0.000 description 7
- 239000000243 solution Substances 0.000 description 6
- 238000007613 slurry method Methods 0.000 description 5
- 238000007796 conventional method Methods 0.000 description 4
- 238000002441 X-ray diffraction Methods 0.000 description 3
- 238000010306 acid treatment Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000000151 deposition Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005868 electrolysis reaction Methods 0.000 description 2
- 239000003792 electrolyte Substances 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 229910001437 manganese ion Inorganic materials 0.000 description 1
- 229940099596 manganese sulfate Drugs 0.000 description 1
- 235000007079 manganese sulphate Nutrition 0.000 description 1
- 239000011702 manganese sulphate Substances 0.000 description 1
- SQQMAOCOWKFBNP-UHFFFAOYSA-L manganese(II) sulfate Chemical compound [Mn+2].[O-]S([O-])(=O)=O SQQMAOCOWKFBNP-UHFFFAOYSA-L 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 238000001238 wet grinding Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
- Battery Electrode And Active Subsutance (AREA)
Description
〔産業上の利用分野〕
本発明は乾電池特性に優れた電解二酸化マンガ
ンの製造法の改良法であつて、優れた特性を有す
る電解二酸化マンガン（以下EMDという）を簡
単に得ることができる方法である。
〔従来の技術〕
現在EMDは、第９図のように電解液にマンガ
ン酸化物を懸濁させて電解する方法（以下スラリ
ー法という）によつて陽極板上にEMDを析出さ
せ、これを陽極板から剥離し、さらに湯洗浄、微
粉砕、さらに湯洗浄した後、中和、乾燥して製品
とする。
一般にEMDで乾電池用に使用されるものは、
通常MnO290〜92％、その他のMn分はMn3O4、
Mn2O3又はMnOの如き低級酸化物であつて、こ
れらの低級酸化物は乾電池特性上好ましくない。
そのため、かゝる低級酸化物を除去するため希硫
酸の存在下で湿式粉砕する事が知られており（特
公昭51−24999号公報）、また、剥離品の荒砕きし
たものを硫酸に浸漬処理することも知られている
（特公昭59−33544号公報）。
しかし、前述湿式粉砕法は工程が繁雑であるば
かりか製品EMDが緻密な結晶状のものであるた
め粉砕が困難であつて低級酸化物の除去は必らず
しも充分ではない。また、硫酸に浸漬処理する方
法は低級酸化物の除去はかなり効果があるもの
の、得られたEMDのγ・MnO2に乾電池特性上
好ましからざるβ・MnO2が存在するという欠点
がある。
〔本発明が解決しようとする問題点〕
本発明者は、前記のように、荒砕きしたEMD
を希硫酸に浸漬した場合製品EMDのγ・MnO2
にβ・MnO2が存在する点につき研究の結果、希
硫酸処理をするとき処理液中にマンガンイオンが
存在すると、製品EMD中のγ・MnO2がβ・
MnO2に変化することを発見し、かかるβ・
MnO2の生成を阻止して乾電池特性に優れた
EMDを製造する方法を提供することにある。
〔問題点を解決するための手段〕
本発明は電解液にマンガン酸化物を懸濁させて
電解し、陽極板上にEMDを析出させ、これを剥
離して製品とするに当り、剥離し、荒砕きしたも
のを微粉砕し、前記微粉砕品を湯洗浄することに
よつてマンガンイオンを除去した後、希硫酸で洗
浄処理し、ついで水洗、中和、乾燥することによ
つてβ−MnO2のほとんどないEMDを製造する
方法である。
〔作用、効果〕
本発明は以上の如き構成のものからなり、電解
処理は所謂スラリー法による電解によつて陽極板
上にEMDを析出させ、該EMDを剥離した後、湯
洗浄、微粉砕、湯洗浄する。
本発明は、前述によつて得られたEMDを微粉
砕した後、充分に湯洗浄し、希硫酸で洗浄する。
この場合EMDの微粉砕品は平均粒径40〜50μ程度
または必要により平均粒径15〜30μ程度とする。
また、希硫酸の濃度は５〜７％、好ましくは５
〜10％、処理温度は室温〜80℃、好ましくは40〜
60℃、また処理時間は５〜60分、好ましくは20〜
40分程度とする。
前記のように微粉砕したEMDを充分に湯洗浄
することによつて希硫酸で洗浄するときの処理液
中のMn+2イオンは大巾に減少でき、従つてMn+2
イオンの存在によつて生ずるγ・MnO2のβ・
MnO2への変換を阻止することができる。
第１図は本発明の一実施例のフローシートであ
るが、スラリー法によつて陽極板上に析出した
EMDを剥離し、湯洗浄、粗粉砕、微粉砕したも
のを充分に湯洗浄した後、希硫酸で洗浄処理し、
その後充分に水洗した後、常法に従つて中和、乾
燥して製品とする。
第２図及び第３図は、希硫酸処理のときの処理
液中にMn+2イオンが存在していない場合及び
Mn+2イオンが存在している場合のＸ線回析図を
夫々示したものであるが、第２図のように処理液
中にMn+2イオンが存在していない場合には、
γ・MnO2のピークが認められるが、β・MnO2
のピークは認められない。これに対し、処理液中
にMn+2イオンが存在している場合にはβ・
MnO2のピークが認められる。
以上のように微粉砕したEMDを充分に湯洗浄
した後希硫酸で洗浄し、さらに、充分に水洗する
ことによつてEMDはγ・MnO2からβ・MnO2へ
の変化を阻止することができるが、このようにし
て得られたEMDは、後述の実施例に明らかなよ
うに、極めて乾電池特性の優れたEMDである。
また、希硫酸処理を行うと、前述したように製
品EMD中の低級酸化物が除去されるため、EMD
自体の気孔率が若干大きくなるので、乾電池を製
造する場合、ZnCl2等の電解液の保液性が良くな
るという効果もある。
以上の如く本発明は、微粉砕したEMDをたん
に硫酸に浸漬せず、希硫酸で洗浄し、さらに充分
に水洗するという工程を付加することによつて
β・MnO2のない実質的にγ・MnO2からなる
EMDを製造でき、従つてさらに乾電池特性の向
上したEMDを簡単に製造することができる。
〔実施例〕
以下本発明を実施例によつて具体的に説明す
る。スラリー法によつて陽極板上に析出した
EMDを剥離し、湯洗した後、乾燥し荒砕きし、
さらに微粉砕する。尚、この場合スラリー法の電
解は200の内容積の電解槽に、陰極として黒鉛
板、陽極としてチタン板を懸吊し、１モル／濃
度の硫酸マンガン溶液を電解液とし、さらに該電
解液に30μ以下に粉砕した二酸化マンガンを0.1
ｇ／添加して懸濁せしめ、1.6A／２m2で電解
した。
つぎに前記によつて得られたEMDの微粉砕品
を充分に湯洗浄した後、10％の希硫酸を用い、温
度40〜60℃、処理時間60分で希硫酸洗浄した。こ
のとき処理液中のMn+2イオンの濃度は、1.0ｇ／
以下であつた。ついで充分に水洗した後、常法
に従つて中和、乾燥して製品とした。
第４図乃至第８図は本発明で得られたEMDの
乾電池特性を示したものであり、また第１表は本
発明で得られたEMDと希硫酸洗浄をしないもの
との乾電池特性を示したものである。
[Industrial Application Field] The present invention is an improved method for producing electrolytic manganese dioxide having excellent properties for dry batteries, and is a method for easily obtaining electrolytic manganese dioxide (hereinafter referred to as EMD) having excellent properties. be. [Conventional technology] Currently, EMD is performed by depositing EMD on an anode plate using a method of suspending manganese oxide in an electrolytic solution and electrolyzing it (hereinafter referred to as the slurry method), as shown in Figure 9. It is peeled off from the board, washed with hot water, pulverized, washed with hot water, neutralized, and dried to produce a product. Generally, EMD is used for dry cell batteries.
Usually MnO 2 90-92%, other Mn content is Mn 3 O 4 ,
It is a lower oxide such as Mn 2 O 3 or MnO, and these lower oxides are unfavorable from the viewpoint of dry battery characteristics.
Therefore, it is known to perform wet grinding in the presence of dilute sulfuric acid in order to remove such lower oxides (Japanese Patent Publication No. 51-24999). It is also known to process (Japanese Patent Publication No. 59-33544). However, the above-mentioned wet pulverization method not only involves a complicated process but also has difficulty in pulverizing the product EMD because it is in a dense crystalline state, and removal of lower oxides is not always sufficient. In addition, although the method of immersion treatment in sulfuric acid is quite effective in removing lower oxides, it has the disadvantage that the resulting EMD contains γ-MnO 2 and β-MnO 2 which is unfavorable from the viewpoint of dry battery characteristics. [Problems to be solved by the present invention] As mentioned above, the present inventors have solved the problem by
γ・MnO 2 of product EMD when immersed in dilute sulfuric acid
As a result of research on the existence of β・MnO 2 in
discovered that it changes to MnO 2 , and that β・
Excellent dry battery characteristics by preventing the formation of MnO 2
The purpose of the present invention is to provide a method for manufacturing EMD. [Means for solving the problem] The present invention suspends manganese oxide in an electrolytic solution, electrolyzes it, deposits EMD on the anode plate, and peels it off to make a product. After pulverizing the coarsely crushed material and washing the finely pulverized product with hot water to remove manganese ions, it is washed with dilute sulfuric acid, and then washed with water, neutralized, and dried to produce β-MnO. This is a method of manufacturing EMD with almost no 2 . [Operations and Effects] The present invention has the above-mentioned configuration, and the electrolytic treatment includes depositing EMD on the anode plate by electrolysis using a so-called slurry method, peeling off the EMD, and then washing with hot water, pulverizing, and pulverizing. Wash with hot water. In the present invention, after the EMD obtained as described above is pulverized, it is thoroughly washed with hot water and then washed with dilute sulfuric acid.
In this case, the finely pulverized EMD product has an average particle size of about 40 to 50 μm or, if necessary, an average particle size of about 15 to 30 μm. Also, the concentration of dilute sulfuric acid is 5 to 7%, preferably 5%.
~10%, processing temperature is room temperature ~80℃, preferably 40~
60℃, and treatment time is 5 to 60 minutes, preferably 20 to 60 minutes.
Approximately 40 minutes. By thoroughly washing the finely ground EMD with hot water as described above, the Mn +2 ions in the treatment solution when washing with dilute sulfuric acid can be greatly reduced .
γ and β of MnO 2 caused by the presence of ions.
Conversion to MnO 2 can be prevented. FIG. 1 is a flow sheet of one embodiment of the present invention, in which deposits were deposited on an anode plate by a slurry method.
After peeling off the EMD, washing it with hot water, coarsely pulverizing it, and pulverizing it finely, wash it thoroughly with hot water, and then wash it with dilute sulfuric acid.
After that, the product is thoroughly washed with water, neutralized and dried according to conventional methods. Figures 2 and 3 show cases where Mn +2 ions are not present in the treatment solution during dilute sulfuric acid treatment and
The X-ray diffraction diagrams are shown in the case where Mn +2 ions are present, but as shown in Figure 2, when Mn +2 ions are not present in the processing solution,
Although the peak of γ・MnO 2 is observed, the peak of β・MnO 2
No peak is observed. On the other hand, when Mn +2 ions are present in the treatment solution, β・
A MnO 2 peak is observed. As mentioned above, EMD can be prevented from changing from γ・MnO 2 to β・MnO 2 by thoroughly washing the finely ground EMD with hot water, then washing with dilute sulfuric acid, and then washing thoroughly with water. However, the EMD thus obtained is an EMD with extremely excellent dry battery characteristics, as will be clear from the examples described later. In addition, as mentioned above, dilute sulfuric acid treatment removes lower oxides in product EMD, so EMD
Since its own porosity increases slightly, it also has the effect of improving the ability to retain electrolytes such as ZnCl 2 when manufacturing dry batteries. As described above, the present invention does not simply immerse finely ground EMD in sulfuric acid, but adds the steps of washing it with dilute sulfuric acid and then thoroughly washing it with water.・Consists of MnO2
EMD can be manufactured, and therefore, EMD with further improved dry battery characteristics can be easily manufactured. [Examples] The present invention will be specifically explained below using examples. Deposited on the anode plate by slurry method
After peeling off the EMD and washing it with hot water, dry it and crush it.
Further pulverize. In this case, slurry method electrolysis is carried out by suspending a graphite plate as a cathode and a titanium plate as an anode in an electrolytic cell with an internal volume of 200 ml, using a 1 mol/concentration manganese sulfate solution as an electrolyte, and adding 0.1 manganese dioxide crushed to 30μ or less
g/g was added and suspended, and electrolyzed at 1.6 A/2 m 2 . Next, the finely ground EMD product obtained above was thoroughly washed with hot water, and then washed with dilute sulfuric acid at a temperature of 40 to 60° C. for 60 minutes using 10% dilute sulfuric acid. At this time, the concentration of Mn +2 ions in the treatment solution was 1.0 g/
It was below. After washing thoroughly with water, the product was neutralized and dried according to a conventional method. Figures 4 to 8 show the dry cell characteristics of the EMD obtained by the present invention, and Table 1 shows the dry cell characteristics of the EMD obtained by the present invention and one not washed with dilute sulfuric acid. It is something that
【表】
第１表及び第４図乃至第８図から本発明によつ
て得られたEMDの乾電池特性が優れていること
が認められる。[Table] From Table 1 and FIGS. 4 to 8, it is recognized that the EMD obtained according to the present invention has excellent dry battery characteristics.
第１図は本発明の一実施例のフローシート、第
２図は本発明で得られたEMDのＸ線回析図の一
例、第３図は従来法で得られたEMDのＸ線回析
図、第４図はEMDの硫酸当量に対するアルカリ
初電位のグラフの一例、第５図は、EMDの液中
マンガン濃度に対するアルカリ初電位のグラフの
一例、第６図は硫酸処理温度及び時間とアルカリ
初電位との関係を示すグラフの一例、第７図は
EMDの硫酸当量に対するアルカリ放電容量のグ
ラフの一例、第８図はEMDの硫酸当量に対する
MnO2／Ｔ・Mnのグラフの一例、第９図は従来
法のフローシートである。
Fig. 1 is a flow sheet of an embodiment of the present invention, Fig. 2 is an example of an X-ray diffraction diagram of EMD obtained by the present invention, and Fig. 3 is an X-ray diffraction diagram of EMD obtained by the conventional method. Figure 4 is an example of a graph of initial alkaline potential against sulfuric acid equivalent of EMD, Figure 5 is an example of a graph of initial alkaline potential against manganese concentration in EMD liquid, and Figure 6 is sulfuric acid treatment temperature and time and alkali initial potential. An example of a graph showing the relationship with the initial potential, Figure 7 is
An example of a graph of alkaline discharge capacity against sulfuric acid equivalent of EMD, Figure 8 is against sulfuric acid equivalent of EMD.
An example of the graph of MnO 2 /T·Mn, FIG. 9, is a flow sheet of the conventional method.
Claims (1)
し、陽極板上に二酸化マンガンを析出させ、これ
を剥離して製品とするに当り、剥離し、荒砕きし
たものを微粉砕し、前記微粉砕品を湯洗浄した後
希硫酸で洗浄処理し、ついで水洗、中和せしめる
ことを特徴とする電解二酸化マンガンの製造法。1 Manganese oxide is suspended in an electrolytic solution and electrolyzed to precipitate manganese dioxide on the anode plate, and when this is peeled off to produce a product, the peeled and crushed product is finely ground, and the finely ground A method for producing electrolytic manganese dioxide, which is characterized in that a pulverized product is washed with hot water, then washed with dilute sulfuric acid, and then washed with water and neutralized.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61165380A JPS6321224A (en) | 1986-07-14 | 1986-07-14 | Production of electrolytic manganese dioxide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61165380A JPS6321224A (en) | 1986-07-14 | 1986-07-14 | Production of electrolytic manganese dioxide |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6321224A JPS6321224A (en) | 1988-01-28 |
| JPH044252B2 true JPH044252B2 (en) | 1992-01-27 |
Family
ID=15811277
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61165380A Granted JPS6321224A (en) | 1986-07-14 | 1986-07-14 | Production of electrolytic manganese dioxide |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6321224A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES2119000T3 (en) * | 1993-09-30 | 1998-10-01 | Mitsui Mining & Smelting Co | COMPOSITION OF CATHODIC ACTIVE MATERIAL FOR DRY BATTERIES, METHOD FOR PREPARATION AND ALKALINE ACCUMULATORS. |
| US8734992B2 (en) | 2007-02-14 | 2014-05-27 | Tosoh Corporation | Electrolytic manganese dioxide, and method for its production and its application |
| JP6115174B2 (en) * | 2012-02-21 | 2017-04-19 | 東ソー株式会社 | Electrolytic manganese dioxide, method for producing the same, and use thereof |
-
1986
- 1986-07-14 JP JP61165380A patent/JPS6321224A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6321224A (en) | 1988-01-28 |
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