JPS59223236A - Production of high purity manganese compound - Google Patents

Production of high purity manganese compound

Info

Publication number
JPS59223236A
JPS59223236A JP9822583A JP9822583A JPS59223236A JP S59223236 A JPS59223236 A JP S59223236A JP 9822583 A JP9822583 A JP 9822583A JP 9822583 A JP9822583 A JP 9822583A JP S59223236 A JPS59223236 A JP S59223236A
Authority
JP
Japan
Prior art keywords
manganese
hydrothermal treatment
compd
slurry
manganese sulfate
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.)
Granted
Application number
JP9822583A
Other languages
Japanese (ja)
Other versions
JPH0310578B2 (en
Inventor
Kazuaki Yamamura
山村 和昭
Ryohei Ishikawa
石川 遼平
Hiroshi Takeda
博 竹田
Shoji Sato
佐藤 昭次
Shingo Tanida
谷田 真吾
Hiroshi Ochiai
弘 落合
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Chuo Denki Kogyo Co Ltd
Original Assignee
Chuo Denki Kogyo Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Chuo Denki Kogyo Co Ltd filed Critical Chuo Denki Kogyo Co Ltd
Priority to JP9822583A priority Critical patent/JPS59223236A/en
Publication of JPS59223236A publication Critical patent/JPS59223236A/en
Publication of JPH0310578B2 publication Critical patent/JPH0310578B2/ja
Granted legal-status Critical Current

Links

Abstract

PURPOSE:To produce easily and inexpensively a titled compd. by using raw materials of low to high concn. by subjecting a slurry formed by adding aq. ammonia to an aq. manganese sulfate soln. to a hydrothermal treatment at a high temp. and high pressure in the presence of gaseous oxygen. CONSTITUTION:A slurry of about 9.1-9.6 pH obtd. by adding aq. ammonia to an aq. manganese sulfate soln. is subjected to a hydrothermal treatment in a gaseous oxygen atmosphere kept at about 80-200 deg.C and about 10-30kg/cm<2>, by which a manganese compd. is produced. The manganese compd. of high purity (beta-MnOOH, gamma-MnOOOH, Mn2O3, MnO2, etc.) is produced easily on an industrial scale by using the aq. manganese soln. of low to high concn. without requiring costly raw materials according to the above-mentioned method. The manganese compd. of a desired kind is obtd. by selecting the conditions for the hydrothermal treatment.

Description

【発明の詳細な説明】 MnOOHや各種酸化マンガンは、磁気フ′エライドヘ
ッドや触媒等の原料として重要な化合物である。
DETAILED DESCRIPTION OF THE INVENTION MnOOH and various manganese oxides are important compounds as raw materials for magnetic ferride heads, catalysts, and the like.

特に、最近は耐摩耗性の優れた磁気へッドフエライトの
開発が進められており、そのためには該フエライトのマ
ンガン原料として高純度で特定の結晶形状を有するMn
OOHが要求されている。また、環境の保全という観点
から、種々のプロセスから排出される廃水中の希薄なマ
ンガンを除去、利用して、上記のごとき有用な化合物を
得る方法も各種考案されている。
In particular, the development of magnetic head ferrite with excellent wear resistance has been progressing recently, and for this purpose, Mn having high purity and a specific crystal shape is required as a manganese raw material for the ferrite.
OOH is requested. In addition, from the viewpoint of environmental conservation, various methods have been devised to remove and utilize dilute manganese in wastewater discharged from various processes to obtain the above-mentioned useful compounds.

特開昭!;0ーg0297号には、配向性フェライトの
マンガン原料として有用な針状のγ−MnOOHを得る
のに好適であると称される方法が記載されている。この
方法によれば、硫酸マンガンの水溶液にアンモニア水と
過酸化水素水を同時に添加することによって、従来より
も短かい熟成時間で上記MnOOHが得られるとされて
いる。しかしながら、現実には該方法は、上記反応後5
0時間にわたる空気中の熟成を必要としており、依然と
して時間を消費する方法であることには変りがない。更
に、この特開昭Sθ−g0297号の方法は、高価な過
酸化水素を使用している点においても不利である。また
、このような方法によってどの程度のマンガン品位の生
成物が得られるかも明らかでない。
Tokukai Akira! No. 0-g0297 describes a method said to be suitable for obtaining acicular γ-MnOOH useful as a manganese raw material for oriented ferrite. According to this method, by simultaneously adding aqueous ammonia and aqueous hydrogen peroxide to an aqueous solution of manganese sulfate, it is said that the above-mentioned MnOOH can be obtained in a shorter aging time than conventional methods. However, in reality, the method requires 5
It remains a time-consuming process, requiring 0 hours of aging in air. Furthermore, the method of JP-A-Sho Sθ-g0297 is disadvantageous in that it uses expensive hydrogen peroxide. It is also unclear what manganese grade products can be obtained by such methods.

特開昭左0−67g77号公報には、やはり配向性フェ
ライトの原料として有益であると称される板状ないしは
鱗片状のβ−MnOOHを製造するための方法が示唆さ
れている。この方法も、硫酸マンガン溶液にアンモニア
水と過酸化水素水を添加するものであり、過酸化水素を
使用する点において不利である。また、該方法に従えば
、所望のMn0OHを得るためには、硫酸マンがン溶液
の濃度は/、θ規定以下(すなわち、マンガンの濃度は
55/2  = 、27.t f/l以下)でなければ
ならないとされており、したがって、該Mn0OHを工
業的に大量生産するには適していない。また、この特開
昭!0−67g77号に示唆されている方法においても
、どの程度のマンガン品位の生成物が得られているか定
かでない。
JP-A No. 0-67g77 suggests a method for producing plate-like or scale-like β-MnOOH, which is also said to be useful as a raw material for oriented ferrite. This method also involves adding aqueous ammonia and aqueous hydrogen peroxide to the manganese sulfate solution, and is disadvantageous in that hydrogen peroxide is used. Furthermore, according to the method, in order to obtain the desired Mn0OH, the concentration of the manganese sulfate solution must be below /, θ (i.e., the concentration of manganese must be below 55/2 = , 27.t f/l). Therefore, it is not suitable for industrial mass production of Mn0OH. Also, this Tokukai Akira! Even in the method suggested in No. 0-67g No. 77, it is not clear how much manganese grade the product is obtained.

Mn0OH等のマンガン化合物を得るためには、硫酸マ
ンガン水溶液を空気酸化する研究も幾つか行なわれてい
る。例えば、「樋口ら:日本鉱業会誌、9g、6コ左〜
6.2gCI9gλ)」には、アルカリ領域における硫
酸マンガン水溶液の空り酸化に関する研究が報告されて
いる。この論文においては、NaOHが添加された高p
H斌の硫酸マンガン水溶液に常圧下で02− N2混合
ガスを吹込むことによつ1β−MnOOHが生成される
と報告されている。しかしながら、このような方法は、
該論文の著者も認めているように、所望の反応を促、進
させるためにガスの吹込みに際して流体力学的条件の制
御が必要である。したがって、このような方法を工業的
規模で実施するには、解決すべき問題が幾つか残されて
いる。また、この論文に記載された方法は、きわめて稀
薄なマンガン含有溶液(Mn(OH)2  として0.
0 / mol/g )を空気酸化するものであり、し
たがって、単なるマン、fイ含有廃水の処理には適用さ
れるであろうが、フェライトや触亦を実用的却、枠で製
造するに際して使用されることには適していない。
In order to obtain manganese compounds such as Mn0OH, several studies have been conducted on air oxidation of manganese sulfate aqueous solutions. For example, “Higuchi et al.: Journal of the Japan Mining Association, 9g, 6th left ~
6.2gCI9gλ)'' reports a study on empty oxidation of an aqueous manganese sulfate solution in an alkaline region. In this paper, high p
It has been reported that 1β-MnOOH is produced by blowing 02-N2 mixed gas into a manganese sulfate aqueous solution under normal pressure. However, such a method
As acknowledged by the authors of the article, control of the hydrodynamic conditions during gas injection is necessary to promote and advance the desired reaction. Therefore, several problems remain to be solved before implementing such a method on an industrial scale. The method described in this paper also uses an extremely dilute manganese-containing solution (Mn(OH)2 of 0.
0/mol/g), and therefore, it may be applied to the treatment of wastewater containing ferrite and filament, but it is not used for practical purposes when manufacturing ferrite and catalysts in frames. Not suitable for being treated.

そこで、本発明の目的は、原料となるマンガン含有溶液
の適用濃度範囲が広<、シかも、経済的で短時間にマン
ガン化合物を製造することができる方法を提供すること
にある。
SUMMARY OF THE INVENTION An object of the present invention is therefore to provide an economical method for producing a manganese compound in a short time, with a wide applicable concentration range of a manganese-containing solution as a raw material.

本発明の該目的は、硫酸マンガン水溶液にアンモニア水
を添加した得たスラリな、酸素ガスの存在下に高温、高
圧で水熱処理することにより達成される。このような本
発明の方法によって、。
The object of the present invention is achieved by hydrothermally treating a slurry obtained by adding ammonia water to an aqueous manganese sulfate solution at high temperature and high pressure in the presence of oxygen gas. By such a method of the present invention.

β−MnOOH、r−MnOOH、Mn2O3、Mn3
O4、および1Mn O2等から成るマンガン化合物が
得られる。水熱処理の条件は、本発明の方法を実施する
目的、所望のマンガン化合物の種類や品位に依存する。
β-MnOOH, r-MnOOH, Mn2O3, Mn3
A manganese compound consisting of O4, 1Mn O2, etc. is obtained. The conditions for the hydrothermal treatment depend on the purpose of carrying out the method of the present invention and the type and quality of the desired manganese compound.

酸素ガスの存在は1.単独の酸素ガスを導入することに
よって得られるが、酸素ガスと不活性ガス(例えば、窒
素)の混合物または空気を用いてもよい。
The presence of oxygen gas is 1. This can be achieved by introducing oxygen gas alone, but a mixture of oxygen gas and an inert gas (eg nitrogen) or air may also be used.

本発明渚は、磁気ヘッド用のフェライトの原料。The present invention is a raw material for ferrite for magnetic heads.

として用いられるような針状のγ−MnOOHを中心と
するマンガン化合物を高純度で得るための条件も見出し
ている。かくして、本発明の好ましい態様に従えば、硫
酸マンガン水溶液にアンモニア水を添加してpnをり、
/より大きく且つり、6以下に調整したスラリーを、g
O−20θ℃の温度下、/θ〜30 KV−の圧力の酸
素ガス零囲気中で水熱処理することを特徴とするマンガ
ン化合物の製造方法が提供される。
We have also found conditions for obtaining highly pure manganese compounds, mainly acicular γ-MnOOH, which can be used as . Thus, according to a preferred embodiment of the present invention, pn is removed by adding aqueous ammonia to an aqueous solution of manganese sulfate,
/ The slurry adjusted to be larger than 6 and less than 6 g
Provided is a method for producing a manganese compound, which comprises hydrothermal treatment at a temperature of 0-20[theta]C in an oxygen gas atmosphere at a pressure of /[theta]~30 KV-.

すなわち、硫酸マンガン水溶液にアンモニア水を添加し
たスラリー(Mt(OH)2  を含む)のp)iが9
、/以下で水熱処理を行なうと、得られる生成物中のマ
ンガンの歩留りが悪くなる。他方、J))lが9.6よ
り大きくなると、原料の硫酸マンガン中のCaやMP等
の不純物が生成物中に残存する。また、水熱処理の温度
が30℃より但くなっても、生成物中のマンガン歩留り
が悪くなり、不純物が多くなる。しかしながら、水熱処
理の温度を300℃より高くすることは、熱エネルギー
を浪費するので好ましくない。更に、水熱処理の酸素圧
カが低すぎても、生成物中のマンガン歩留りが悪くなっ
たり不純物が多くなるので、該圧力はg Kg/d以上
とすべきである。他方、水熱処理時の圧力を30Kg/
a4より高くしても耐圧設備に費用を要するが格別に顕
著な効果は得られない。
That is, p)i of the slurry (containing Mt(OH)2) obtained by adding aqueous ammonia to an aqueous solution of manganese sulfate is 9.
If the hydrothermal treatment is performed below ,/, the yield of manganese in the resulting product will be poor. On the other hand, when J))l is larger than 9.6, impurities such as Ca and MP in the raw material manganese sulfate remain in the product. Furthermore, even if the temperature of the hydrothermal treatment is lower than 30° C., the yield of manganese in the product becomes poor and the amount of impurities increases. However, it is not preferable to raise the temperature of the hydrothermal treatment higher than 300° C. because thermal energy is wasted. Furthermore, if the oxygen pressure in the hydrothermal treatment is too low, the manganese yield in the product will be poor or the amount of impurities will increase, so the pressure should be at least g Kg/d. On the other hand, the pressure during hydrothermal treatment was set to 30 kg/
Even if the pressure is set higher than a4, the pressure-resistant equipment will be expensive, but no particularly significant effect will be obtained.

しかしながら、本発明の方法においては、原料として片
いられる硫酸マンガン水溶液の濃度に特に制限は存しな
い。すなわち、本発明のマンガン化合物の製造方法は、
極めて稀薄な硫酸マンガン水溶液、例えば、/θ00 
ppm程度のマンガン濃度の硫酸マンガンを含有する廃
水を用いることもでき、したがって、そのような廃水を
処理する面も韮持している。勿論、本発明の方法は、フ
ェライトや触媒の原料となるマンガン化合物を工業的規
模で製造するのに実施されることもでき、そのような場
合には、さらに高濃度、例えば、/!;0〜200ψの
マンガン濃度を有する硫酸マンガン水溶液が使用される
However, in the method of the present invention, there is no particular restriction on the concentration of the manganese sulfate aqueous solution used as a raw material. That is, the method for producing a manganese compound of the present invention includes:
Extremely dilute aqueous manganese sulfate solution, e.g. /θ00
It is also possible to use wastewater containing manganese sulfate at a manganese concentration of about ppm, and therefore, there are advantages in treating such wastewater. Of course, the method of the present invention can also be carried out to produce manganese compounds, which are raw materials for ferrite and catalysts, on an industrial scale, and in such cases even higher concentrations, for example /! ; An aqueous manganese sulfate solution having a manganese concentration of 0 to 200 ψ is used.

本発明に従えば、上記のごとき水熱処理によって非常に
短時間でγ−MnOOHのごときマンガン化合物を得る
ことができ、従来の方法におけるような長時間の熟成を
必要としない。すなわち、本発明の方法における典型的
な水熱処理は、所定温度までに約7時間で昇温し、該所
定温度に約7〜λ時間保持した後、約7時間で室温まで
冷却することによって行なわれる。
According to the present invention, a manganese compound such as γ-MnOOH can be obtained in a very short time by the hydrothermal treatment as described above, and there is no need for long-term aging as in conventional methods. That is, a typical hydrothermal treatment in the method of the present invention is carried out by raising the temperature to a predetermined temperature in about 7 hours, maintaining the temperature at the predetermined temperature for about 7 to λ hours, and then cooling it to room temperature in about 7 hours. It will be done.

以上の説明から明らかなように、本発明に従えば、特に
高価な原料を必要とせずに、低濃度から高濃度の硫酸マ
ンガン水溶液を用いてマンガン化合物を経済的且つ容易
忙大量に製造することが回部となる。
As is clear from the above description, according to the present invention, manganese compounds can be produced economically and easily in large quantities using manganese sulfate aqueous solutions of low to high concentrations without the need for particularly expensive raw materials. becomes the turning part.

以下、本発明を比較例および実施例に沿って説明する。Hereinafter, the present invention will be explained along with comparative examples and examples.

比較例 表/忙示すようにマンガン濃度/gダψの硫酸マンガン
水溶液−〇〇−に2NのNH4OHを加えてpHワ、乙
のスラリーを得た。このスラリーをろ過、水洗後、乾燥
して得た固形物を分析すると第2表のようになった。こ
の第2表から理解されるように、マンガン歩留は!rに
、2%と低く、また、CaやMIP等の不純物の量も太
きい。
Comparative Example Table/As shown in Table 1, 2N NH4OH was added to a manganese sulfate aqueous solution -〇〇- with a manganese concentration/g da ψ to obtain a slurry with a pH of 〇〇. This slurry was filtered, washed with water, and the solid matter obtained was analyzed, as shown in Table 2. As can be understood from this Table 2, the manganese yield is! r is as low as 2%, and the amount of impurities such as Ca and MIP is also large.

第1表 硫酸マンガン水溶液組成 第2表 比較例生成物の品位(%) 実施例 前述の第1表の品位を有する硫酸マンガン水溶液λθo
mt、に2NのNH4OH(アンモニア水)を加えて第
3表に示すような各pHを有するスラリーな鯛製した。
Table 1 Manganese sulfate aqueous solution composition Table 2 Comparative Example product quality (%) Example Manganese sulfate aqueous solution having the quality shown in Table 1 above λθo
2N NH4OH (ammonia water) was added to mt to prepare slurry sea bream having various pH values as shown in Table 3.

各スラリーを内容826のオートクレーブ中に入れ、第
3表に示す各圧力の酸素を封入し、約7時間で/ 、t
 9 ℃まで昇温し、該温度に/時間保持稜、室温まで
冷却した。このように水熱処理したスラリーを、ろ過、
水洗、乾燥後分析す”ゝると第3表のようになった。
Each slurry was placed in an autoclave with a content of 826 and filled with oxygen at each pressure shown in Table 3, for about 7 hours/, t.
The temperature was raised to 9°C, held at that temperature for 1 hour, and cooled to room temperature. The hydrothermally treated slurry is filtered,
After washing with water and drying, the results were analyzed as shown in Table 3.

第3表に示すように、本発明に従う水熱処理に  〜よ
り得られる生成物は不純物の量が激減されており、更に
、9.7よりも大きいphのスラリーを水熱処理すると
マンガン歩留が極めて高くなる。また、得られた生成物
(実施例り)を顕微鏡で観察すると、第1図及び第2図
のようになh、r二Mn0OHを主成分とする針状のマ
ンガン化合物の存在が認められる。
As shown in Table 3, the amount of impurities in the product obtained by the hydrothermal treatment according to the present invention is drastically reduced, and furthermore, when the slurry with a pH greater than 9.7 is hydrothermally treated, the manganese yield is extremely low. It gets expensive. Furthermore, when the obtained product (Example) is observed under a microscope, the presence of acicular manganese compounds containing h,r2Mn0OH as the main components, as shown in FIGS. 1 and 2, is observed.

【図面の簡単な説明】[Brief explanation of drawings]

第1図および第2図は、本発明によって得られたマンガ
ン化合物あそれぞれ、3000倍およびtooo倍の電
子顕微鏡写真である。
FIGS. 1 and 2 are electron micrographs of manganese compounds obtained by the present invention, magnified 3000 times and too much, respectively.

Claims (2)

【特許請求の範囲】[Claims] (1)  硫酸マンガン水溶液にアンそニア水を添加し
て得たスラリーを、酸素ガスの存在下に高温、高圧で水
熱処理することを特徴とするマンガン化合物の製造方法
(1) A method for producing a manganese compound, which comprises hydrothermally treating a slurry obtained by adding anthonia water to an aqueous manganese sulfate solution at high temperature and high pressure in the presence of oxygen gas.
(2)スラリーのpHIがワ、・/より大きく且つヲ尾
以下であり、水熱処理がgO−200℃の温度下で70
〜30 Kq/−の圧力の酸素ガス零囲気中で行なわれ
ることを特徴とする特許請求の範囲第(1)項記載のマ
ンガン化合物の製造方法。
(2) The pHI of the slurry is greater than .
The method for producing a manganese compound according to claim 1, wherein the method is carried out in an atmosphere of zero oxygen gas at a pressure of ~30 Kq/-.
JP9822583A 1983-06-02 1983-06-02 Production of high purity manganese compound Granted JPS59223236A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9822583A JPS59223236A (en) 1983-06-02 1983-06-02 Production of high purity manganese compound

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9822583A JPS59223236A (en) 1983-06-02 1983-06-02 Production of high purity manganese compound

Publications (2)

Publication Number Publication Date
JPS59223236A true JPS59223236A (en) 1984-12-15
JPH0310578B2 JPH0310578B2 (en) 1991-02-14

Family

ID=14214015

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9822583A Granted JPS59223236A (en) 1983-06-02 1983-06-02 Production of high purity manganese compound

Country Status (1)

Country Link
JP (1) JPS59223236A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014504252A (en) * 2010-12-20 2014-02-20 ▲海▼洋王照明科技股▲ふん▼有限公司 Manufacturing method and application of manganese dioxide nanorods
JP2014205617A (en) * 2014-06-12 2014-10-30 東ソー株式会社 Manganese oxide and method for producing lithium manganate using the same
CN104445423A (en) * 2014-12-15 2015-03-25 中信大锰矿业有限责任公司大新锰矿分公司 Preparation method of high-purity manganese dioxide
CN108439476A (en) * 2018-04-23 2018-08-24 陕西省膜分离技术研究院有限公司 A kind of preparation of low price Mn oxide, product and synthesizing lithium ion sieve presoma Li1.6Mn1.6O4Application

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5815035A (en) * 1981-07-13 1983-01-28 Isao Tanabe Manufacture of heavy manganese dioxide
JPS5820729A (en) * 1981-07-27 1983-02-07 Chuo Denki Kogyo Kk Preparation of manganese oxide

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5815035A (en) * 1981-07-13 1983-01-28 Isao Tanabe Manufacture of heavy manganese dioxide
JPS5820729A (en) * 1981-07-27 1983-02-07 Chuo Denki Kogyo Kk Preparation of manganese oxide

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014504252A (en) * 2010-12-20 2014-02-20 ▲海▼洋王照明科技股▲ふん▼有限公司 Manufacturing method and application of manganese dioxide nanorods
JP2014205617A (en) * 2014-06-12 2014-10-30 東ソー株式会社 Manganese oxide and method for producing lithium manganate using the same
CN104445423A (en) * 2014-12-15 2015-03-25 中信大锰矿业有限责任公司大新锰矿分公司 Preparation method of high-purity manganese dioxide
CN108439476A (en) * 2018-04-23 2018-08-24 陕西省膜分离技术研究院有限公司 A kind of preparation of low price Mn oxide, product and synthesizing lithium ion sieve presoma Li1.6Mn1.6O4Application
CN108439476B (en) * 2018-04-23 2020-07-28 陕西省膜分离技术研究院有限公司 Preparation of low-valence manganese oxide, product and synthetic lithium ion sieve precursor L i1.6Mn1.6O4Application of

Also Published As

Publication number Publication date
JPH0310578B2 (en) 1991-02-14

Similar Documents

Publication Publication Date Title
US3970738A (en) Process for producing iron oxide products from waste liquids containing ferrous salts
JPS58176123A (en) Superpure boehmite and pseudoboehmite and manufacture thereof
JPS6241721A (en) Method of recovering iron oxide
RU2003107342A (en) METHOD FOR PRODUCING IRON OXIDES
JPH04228428A (en) Zirconia with large surface area
CN111646560A (en) Method for degrading aniline organic matters in water by catalyzing peroxydisulfate
JP3272759B2 (en) Manufacture of trimanganese oxide
JPS59223236A (en) Production of high purity manganese compound
KR101647747B1 (en) Surface modification method of aluminum oxide carrier
CN110560080B (en) Preparation method of cobalt-manganese composite oxide and method for degrading dye wastewater
EP0390257A1 (en) Process for preparing a purified mineral coating
US4448760A (en) Continuous process for the preparation of manganite, MnOOH
US3539337A (en) Production of iron oxide and iron free of manganese
US4052326A (en) Manufacture of γ-iron(III) oxide
JPS59107924A (en) Manufacture of magnetic iron oxide powder containing cobalt
KR100463799B1 (en) A method for manufacturing of cerium carbonate from the cerium hydroxide
KR0136191B1 (en) Refining method of iron oxide
JPH101315A (en) Production of high purity iron oxide powder
US4264570A (en) Method of producing magnesium sulphate
Narita et al. The formation and thermal decomposition of hydrous lead (II) oxide prepared by the alkoxide method.
US4073878A (en) Method for producing yellow hydrated ferric oxide
SU1326591A1 (en) Method of producing ferric oxide pigment
JPH0328379B2 (en)
JPH05208825A (en) Production of manganese hydroxide
SU1030315A1 (en) Method for preparing acicular gamma iron oxide used for producing magnetic carriers