JPH0255382B2 - - Google Patents
Info
- Publication number
- JPH0255382B2 JPH0255382B2 JP20226785A JP20226785A JPH0255382B2 JP H0255382 B2 JPH0255382 B2 JP H0255382B2 JP 20226785 A JP20226785 A JP 20226785A JP 20226785 A JP20226785 A JP 20226785A JP H0255382 B2 JPH0255382 B2 JP H0255382B2
- Authority
- JP
- Japan
- Prior art keywords
- particle size
- reaction
- lepidocrocite
- value
- average particle
- 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
Links
- 238000006243 chemical reaction Methods 0.000 claims description 28
- AEIXRCIKZIZYPM-UHFFFAOYSA-M hydroxy(oxo)iron Chemical compound [O][Fe]O AEIXRCIKZIZYPM-UHFFFAOYSA-M 0.000 claims description 23
- 239000007864 aqueous solution Substances 0.000 claims description 10
- 229960002089 ferrous chloride Drugs 0.000 claims description 7
- NMCUIPGRVMDVDB-UHFFFAOYSA-L iron dichloride Chemical compound Cl[Fe]Cl NMCUIPGRVMDVDB-UHFFFAOYSA-L 0.000 claims description 7
- 239000003513 alkali Substances 0.000 claims description 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 6
- 239000001301 oxygen Substances 0.000 claims description 6
- 229910052760 oxygen Inorganic materials 0.000 claims description 6
- 239000013078 crystal Substances 0.000 claims description 5
- 239000007789 gas Substances 0.000 claims description 5
- 229910006299 γ-FeOOH Inorganic materials 0.000 claims description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 4
- 238000007664 blowing Methods 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 229910021529 ammonia Inorganic materials 0.000 claims description 2
- 239000003518 caustics Substances 0.000 claims description 2
- 229910021506 iron(II) hydroxide Inorganic materials 0.000 claims description 2
- NCNCGGDMXMBVIA-UHFFFAOYSA-L iron(ii) hydroxide Chemical compound [OH-].[OH-].[Fe+2] NCNCGGDMXMBVIA-UHFFFAOYSA-L 0.000 claims description 2
- 239000012670 alkaline solution Substances 0.000 claims 1
- 239000002245 particle Substances 0.000 description 55
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 14
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 238000000034 method Methods 0.000 description 8
- 230000005070 ripening Effects 0.000 description 8
- 239000007858 starting material Substances 0.000 description 8
- 239000000843 powder Substances 0.000 description 7
- 230000032683 aging Effects 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 229910052598 goethite Inorganic materials 0.000 description 5
- 238000003756 stirring Methods 0.000 description 4
- 229910006540 α-FeOOH Inorganic materials 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 3
- 229910001566 austenite Inorganic materials 0.000 description 3
- 229910001873 dinitrogen Inorganic materials 0.000 description 3
- 238000011282 treatment Methods 0.000 description 3
- 238000013459 approach Methods 0.000 description 2
- 239000010941 cobalt Substances 0.000 description 2
- 229910017052 cobalt Inorganic materials 0.000 description 2
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000002585 base Substances 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000005554 pickling Methods 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Compounds Of Iron (AREA)
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明はレピツドクロサイト（γ−FeOOH）
の製造に係り、より詳細には、オーデイオテー
プ、ビデオテープ、磁気カード等の磁気記録媒体
用磁性酸化鉄粉を製造する際に出発物質として好
適なレピツドクロサイトの製造方法の関するもの
である。[Detailed description of the invention] (Industrial application field) The present invention is based on lepidocrocite (γ-FeOOH).
More specifically, it relates to a method for producing lepidocrocite, which is suitable as a starting material when producing magnetic iron oxide powder for magnetic recording media such as audio tapes, video tapes, and magnetic cards. .
（従来の技術及び解決しようとする問題点）
一般に、オーデイオテープ、ビデオテープ、磁
気カード等の磁気記録媒体用の磁性酸化鉄粉は、
α−FeOOH（ゲータイト）又はγ−FeOOH（レ
ピツドクロサイト）を出発物質とし、これに焼成
（脱水、焼きしめ）、還元及び酸化などの処理を順
次に施して針状のγ−Fe2O3（マグヘマイト）を
得、或いはその粒子表面にコバルト変性処理によ
つてコバルト被着したCo−γ−Fe2O3を得ること
により、製造されている。この場合、得られた磁
性酸化鉄粉の磁気特性は上記出発物質の性状に依
存するため、磁気記録媒体に適した磁性酸化鉄粉
末を得るには、優れた性状の出発物質を使用する
必要がある。(Prior art and problems to be solved) In general, magnetic iron oxide powder for magnetic recording media such as audio tapes, video tapes, and magnetic cards is
α-FeOOH (goethite) or γ-FeOOH (lepidocrocite) is used as a starting material, and it is sequentially subjected to treatments such as calcination (dehydration, hardening), reduction, and oxidation to form acicular γ-Fe 2 O. It is produced by obtaining Co-γ-Fe 2 O 3 (maghemite) or Co-γ-Fe 2 O 3 with cobalt deposited on the particle surface by cobalt modification treatment. In this case, the magnetic properties of the obtained magnetic iron oxide powder depend on the properties of the above-mentioned starting material, so in order to obtain magnetic iron oxide powder suitable for magnetic recording media, it is necessary to use a starting material with excellent properties. be.
この点、従来、レピツドクロサイト（γ−
FeOOH）を出発物質として得られる磁性酸化鉄
粉末は、ゲータイト（α−FeOOH）を出発物質
とする場合に比らべ、最終製品であるオーデイオ
テープ、ビデオテープ等々の磁気記録媒体の磁気
的配向性、分散性、角形比、転写特性は優れてい
るにも拘らず、粒度分布が大きいという問鎮題が
あり、最終製品の特性（保磁力、反転磁界強度分
布等）に悪影響を及ぼすという欠点があつた。 In this respect, conventionally, lepidocrocite (γ-
The magnetic iron oxide powder obtained using Goethite (α-FeOOH) as a starting material has a higher magnetic orientation than that of goethite (α-FeOOH) in magnetic recording media such as audio tapes and video tapes. Although it has excellent dispersibility, squareness ratio, and transfer characteristics, it has the problem of a large particle size distribution, which has a negative effect on the properties of the final product (coercive force, reversal magnetic field strength distribution, etc.). It was hot.
ところで、上記出発物質のうちのレピツドクロ
サイトは、通常、以下のような合成反応法で製造
されている。 By the way, among the above starting materials, lepidocrocite is usually produced by the following synthetic reaction method.
まず、酸洗廃液等を利用して得られる塩化第一
鉄（FeCl2）水溶液に苛性アルカリ又はアンモニ
ア等のアルカリ水溶液を加えて中和する。この
際、水酸基と鉄のモル比（OH／Fe）が約0.8〜
1.4となるようにアルカリ水溶液を混合する。 First, an aqueous solution of ferrous chloride (FeCl 2 ) obtained using pickling waste liquid or the like is neutralized by adding an aqueous alkali solution such as caustic alkali or ammonia. At this time, the molar ratio of hydroxyl groups to iron (OH/Fe) is approximately 0.8 to
Mix the alkaline aqueous solution so that the ratio is 1.4.
次いで、これを酸素含有ガス（空気又は酸素）
で酸化してシード反応により種結晶をつくる。こ
のときの反応温度は約10〜25℃とする。シード反
応が終了に近づくと、反応液のPHが低下し、アル
カリ分が完全に消費されて反応が終ると、PH値は
約3.2〜3.8となる。 This is then converted into an oxygen-containing gas (air or oxygen)
to create seed crystals through a seed reaction. The reaction temperature at this time is about 10-25°C. As the seed reaction approaches completion, the pH of the reaction solution decreases, and when the alkaline content is completely consumed and the reaction ends, the pH value will be approximately 3.2 to 3.8.
その後、30〜50℃に昇温し、PH値が約3.5〜4.5
になるように酸素含有ガスを吹込むと共にアルカ
リ水溶液を添加して成長反応を行う。この成長反
応が終了に近づくと、反応速度が遅くなり、PH値
が上昇する。PH値が約5.5になつた時点で反応の
終了とし、針状のレピツドクロサイトを得る。 After that, the temperature is raised to 30-50℃, and the PH value is about 3.5-4.5
A growth reaction is performed by blowing oxygen-containing gas and adding an alkaline aqueous solution so that the growth reaction occurs. As this growth reaction approaches completion, the reaction rate slows down and the pH value increases. The reaction is terminated when the pH value reaches approximately 5.5, and needle-like lepidocrocites are obtained.
しかし乍ら、上記方法では、前述の如く粒度分
布が大きいレピツドクロサイトしか得られず、良
好な性状とは言えず、更には平均粒度をコントロ
ールすることが困難であるため、用途目的に適し
た任意の平均粒度を有するレピツドクロサイトを
提供できないという欠点があつた。このため、磁
性酸化鉄粉末の製造の出発物質としてはゲータイ
ト（α−FeOOH）が多用されているのが現状で
ある。 However, as mentioned above, the above method only yields repitdocrosite with a large particle size distribution, which cannot be said to have good properties, and furthermore, it is difficult to control the average particle size, so it is not suitable for the purpose of use. However, there was a drawback in that it was not possible to provide lepidocrocite having an arbitrary average particle size. For this reason, goethite (α-FeOOH) is currently frequently used as a starting material for producing magnetic iron oxide powder.
本発明は、前述の如く多くの利点を有するレピ
ツドクロサイトにつき、上記従来技術の欠点を解
消し、粒度分布が小さく、かつ、要求される各種
粒度を安定的に有する優れた性状のレピツドクロ
サイトを製造する方法を提供することを目的とす
るものである。 The present invention solves the drawbacks of the prior art, and produces a repito-crocite with excellent properties that have a small particle size distribution and stably have various required particle sizes. The purpose of the present invention is to provide a method for producing docrosite.
（問題点を解決するための手段）
上記目的を達成するため、本発明では、シード
反応により生成する種結晶は大小の粒子が混在す
る状態にあるので、これを次工程で成長せしめる
に先立つて、粒子径を予めコントロールするなら
ば、以降の工程により成長するレピツドクロサイ
トの粒度分布及び平均粒径に好結果をもたらすこ
とを知見し、そのためにシード反応後引続いて処
理液を特定条件にて保持する熟成工程を設けるこ
とを骨子とするものである。(Means for solving the problem) In order to achieve the above object, in the present invention, since the seed crystal generated by the seed reaction has a mixture of large and small particles, it is necessary to prepare the seed crystal before growing it in the next step. It was found that if the particle size is controlled in advance, good results can be obtained in the particle size distribution and average particle size of the repid crocite that grows in the subsequent steps. The main idea is to provide a ripening process in which the product is maintained at
以下に本発明を実施例に基づいて詳細に説明す
る。 The present invention will be explained in detail below based on examples.
本発明における熟成工程は、塩化第一鉄とアル
カリとの混合水溶液を酸化させてγ−FeOOHの
種結晶を生成させるシード反応工程と、アルカリ
水溶液の添加と酸素含有ガスの吹込みを行う成長
反応工程との間に行うもので、混合水溶液のPH値
が3.0〜5.0、温度が10〜50℃の範囲内で10〜120
分間保持する。勿論、シード反応でも成長反応で
もないので、不活性ガス雰囲気等の非酸化性雰囲
気中で行い、また撹拌しつつ行うことは云うまで
もない。混合撹拌状態は、例えば、撹拌羽根の回
転数200〜400rpmとする程度で良い。 The aging process in the present invention includes a seed reaction process in which a mixed aqueous solution of ferrous chloride and an alkali is oxidized to generate γ-FeOOH seed crystals, and a growth reaction in which an aqueous alkali solution is added and an oxygen-containing gas is blown into the seed reaction process. This is done between processes, and the PH value of the mixed aqueous solution is 3.0 to 5.0, and the temperature is 10 to 120 within the range of 10 to 50℃.
Hold for a minute. Of course, since this is neither a seed reaction nor a growth reaction, it goes without saying that it is carried out in a non-oxidizing atmosphere such as an inert gas atmosphere, and is carried out with stirring. The mixing and stirring state may be such that, for example, the rotation speed of the stirring blade is 200 to 400 rpm.
この熟成により、シード反応で生成した粒子の
うち、微小な粒子は溶解して他のそれよりも大き
な粒子表面で析出するので、粒度分布が小さくな
ると共に平均粒径が変化し、均一な粒度分布で所
望の平均粒径を有する粒子を得て、以降の成長反
応工程でのベースとすることができる。そのた
め、保持時間が10分未満では粒度分布の均一化の
効果が充分得られず、10分以上保持する必要があ
る。保持時間は長い程粒度分布を小さく、かつ、
平均粒径を大きくすることができるが、120分を
超えて保持しても粒度分布を均一化する効果がそ
れ以上期待できず、経済的でないので、保持時間
は10〜120分の範囲内とする。 Due to this ripening, among the particles generated by the seed reaction, small particles dissolve and precipitate on the surface of other larger particles, resulting in a smaller particle size distribution and a change in the average particle size, resulting in a uniform particle size distribution. Particles having a desired average particle size can be obtained in this step and used as a base for the subsequent growth reaction step. Therefore, if the holding time is less than 10 minutes, the effect of uniformizing the particle size distribution cannot be sufficiently obtained, and it is necessary to hold the particle size for more than 10 minutes. The longer the holding time, the smaller the particle size distribution, and
Although it is possible to increase the average particle size, holding for more than 120 minutes cannot expect any further effect of making the particle size distribution uniform and is not economical, so the holding time should be within the range of 10 to 120 minutes. do.
また処理溶液のPH値及び温度は、各々3.0以上、
10℃以上とすることにより粒度分布の均一化の効
果を確保でき、しかもそれ以上の高いPH値、温度
にすれば平均粒径をより大きくすることができ
る。しかし、PH値及び温度が各々5.0、50℃を超
えると、その効果は期待できなくなる傾向にある
ので、PH値は3.0〜5.0、温度は10〜50℃の範囲内
とする。 In addition, the PH value and temperature of the treatment solution should be 3.0 or higher, respectively.
By setting the temperature to 10°C or higher, the effect of making the particle size distribution uniform can be ensured, and if the pH value and temperature are higher than that, the average particle size can be further increased. However, if the PH value and temperature exceed 5.0 and 50°C, respectively, the effect tends to be lost, so the PH value should be within the range of 3.0 to 5.0 and the temperature should be within the range of 10 to 50°C.
このように熟成工程の保持時間、PH値及び温度
を適宜コントロールすることにより、粒度分布が
小さく、かつ、任意の平均粒径を有するレピツド
クロサイトを得ることができ、特に従来よりも粒
度分布の小さい針状の優れた性状のものを製造で
きる。 In this way, by appropriately controlling the holding time, PH value, and temperature in the ripening process, it is possible to obtain lepidocrocite with a small particle size distribution and an arbitrary average particle size. It is possible to produce small needle-like products with excellent properties.
勿論、レピツドクロサイトの平均粒径に関して
は、出発原料の塩化第一鉄の溶液濃度等々の熟成
以外の工程条件によつて一定限度内で可変ではあ
るが、本発明によれば、熟成によつて平均粒径を
大幅にコントロールできるので、例えば、目標と
する平均粒径よりも小さ目の値となるようにシー
ド反応条件を設定し、目標値との差を補正するべ
く熟成条件を決めることにより、粒度分布が均一
で、常に一定の平均粒径を有するレピツドクロサ
イトを製造することができる。その際、シード反
応時の平均粒径を測定し、この実測値に基づいて
熟成条件をコントロールするなどの自動化も可能
である。 Of course, the average particle size of lepidocrocite can be varied within a certain limit depending on process conditions other than ripening, such as the concentration of the solution of ferrous chloride as a starting material, but according to the present invention, it is possible to Therefore, the average particle size can be largely controlled, so for example, seed reaction conditions can be set to a value smaller than the target average particle size, and ripening conditions can be determined to compensate for the difference from the target value. This makes it possible to produce lepidocrocite which has a uniform particle size distribution and always has a constant average particle size. At this time, it is also possible to automate the process by measuring the average particle size during the seed reaction and controlling the ripening conditions based on this measured value.
本発明における熟成工程以外の工程は従来と同
様であり、特にそれらの条件は制限されない。但
し、塩化第一鉄を水酸化第一鉄にするのに要する
アルカリの理論量は、シード反応工程と成長工程
とに分けて添加するが、シード反応工程で添加す
る量は、ゲータイトの発生を防止し、針状性の優
れたレピツドクロサイトの粒子を得るため、上記
理論量の0.4〜0.7倍とする必要がある。 The steps other than the aging step in the present invention are the same as conventional ones, and the conditions are not particularly limited. However, the theoretical amount of alkali required to convert ferrous chloride to ferrous hydroxide is added separately in the seed reaction step and the growth step, but the amount added in the seed reaction step is determined to prevent the generation of goethite. In order to prevent this and obtain lepidocrocite particles with excellent acicular properties, the amount needs to be 0.4 to 0.7 times the above theoretical amount.
実施例
濃度0.97モル／の塩化第一鉄水溶液25を窒
素ガス雰囲気に保つた反応器内で撹拌しながら、
濃度0.71モル／の水酸化ナトリウム水溶液42
を添加し、液温を13℃に保ちつつ５気圧（ゲージ
圧）の空気を20／minの速度で吹き込んで酸化
させ、シード反応を行つた。Example While stirring a ferrous chloride aqueous solution 25 with a concentration of 0.97 mol/in a reactor maintained in a nitrogen gas atmosphere,
Sodium hydroxide aqueous solution with a concentration of 0.71 mol/42
was added and oxidized by blowing air at 5 atm (gauge pressure) at a rate of 20/min while maintaining the liquid temperature at 13°C to perform a seed reaction.
シード反応の終了をPH値の測定で確認した後
（PH＝3.2）、空気の吹込みを止め、1.5気圧（ゲー
ジ圧）の窒素ガスを３／minの速度で吹き込み
反応器を不活性雰囲気にした後、PH値、温度及び
保持時間を種々変化させて熟成を行つた。なお、
PH値の変化は水酸化ナトリウム水溶液の添加量に
よつて行つた。 After confirming the completion of the seed reaction by measuring the PH value (PH = 3.2), stop blowing air, and blow nitrogen gas at 1.5 atm (gauge pressure) at a rate of 3/min to create an inert atmosphere in the reactor. After that, ripening was carried out by varying the pH value, temperature and holding time. In addition,
Changes in PH value were determined by the amount of sodium hydroxide aqueous solution added.
その後、窒素ガスに代えて５気圧（ゲージ圧）
の空気を３／minの速度で吹き込むと共に濃度
1.6モル／の水酸化ナトリウム水溶液を80ｇ／
minの一定速度で添加し、PH値が5.5に上昇する
までこの成長反応を行い、針状のレピツドクロサ
イトを得た。 After that, replace the nitrogen gas with 5 atm (gauge pressure).
of air at a speed of 3/min and the concentration
80g/1.6mol/aqueous sodium hydroxide solution
The growth reaction was carried out until the pH value increased to 5.5, and needle-like lepidocrocites were obtained.
得られたレピツドクロサイトについて粒度分布
及び平均粒径を測定した。なお、粒度分布の大き
さは、電子顕微鏡にて粒子の長軸方向の粒径を測
定し、これより求めた粒度分布における標準偏差
値で伴定し、また平均粒径（粒度）の大きさは、
平均粒度と対応関係にあるベツド法比表面積の値
によつて判定した。以上の結果を第１図〜第４図
に示す。 The particle size distribution and average particle diameter of the obtained lepidocrocite were measured. The size of the particle size distribution is determined by measuring the particle size in the long axis direction of the particle using an electron microscope and using the standard deviation value of the particle size distribution obtained from this, and the size of the average particle size (particle size). teeth,
Judgment was made based on the value of the Bed method specific surface area, which corresponds to the average particle size. The above results are shown in FIGS. 1 to 4.
これらの図より、熟成時のPH、温度及び時間を
増すに従つてレピツドクロサイトの比表面積を小
さくすることができ、これらの条件を適宜選択す
れば所望の平均粒度の粒子を製造することが可能
であることがわかる。しかも、第１図に一例とし
て熟成時間に対する標準偏差（粒度分布）の関係
を示すように、これらの条件を本発明の範囲内で
設定するならば、平均粒度を所望のものに変化さ
せても粒度分布の小さい優れた性状のレピツドク
ロサイトを安定的に得ることができることを確認
した。 From these figures, the specific surface area of lepidocrocite can be reduced as the pH, temperature, and time during ripening are increased, and if these conditions are appropriately selected, particles with the desired average particle size can be produced. It turns out that it is possible. Furthermore, as shown in Figure 1, which shows the relationship between standard deviation (particle size distribution) and aging time as an example, if these conditions are set within the scope of the present invention, the average particle size can be changed to a desired value. It was confirmed that lepidocrocite with excellent properties and a small particle size distribution could be stably obtained.
（発明の効果）
以上詳述したように、本発明によれば、レピツ
ドクロサイトの合成反応においてシード反応後に
特定条件の熟成工程を経るので、任意の平均粒径
を有し、しかも粒度分布が極めて小さい優れた性
状の針状レピツドクロサイトを安定して製造する
ことができ、したがつて、優れた特性の磁性酸化
鉄粉末の製造を可能にするものである。(Effects of the Invention) As described in detail above, according to the present invention, in the synthesis reaction of lepidocrocite, an aging step under specific conditions is performed after the seed reaction, so that the particles can have an arbitrary average particle size and have a particle size distribution. It is possible to stably produce acicular lepidocrocite with excellent properties and extremely small particles, and therefore to produce magnetic iron oxide powder with excellent properties.
第１図は熟成時間とレピツドクロサイトの粒度
の標準偏差（粒度分布）との関係を示す図、第２
図〜第４図は各々レピツドクロサイトの比表面積
（平均粒度）とPH、温度又は熟成時間との関係を
示す図である。
Figure 1 is a diagram showing the relationship between aging time and standard deviation of grain size (particle size distribution) of lepidocrocite, Figure 2
Figures 4 to 4 are diagrams showing the relationship between the specific surface area (average particle size) of lepidocrocite and PH, temperature, or aging time.
Claims (1)
ア等のアルカリ水溶液を、該塩化第一鉄を水酸化
第一鉄にするのに要する理論量の0.4〜0.7倍加え
た後、酸素含有ガスを吹込んでγ−FeOOHの種
結晶を生成させ、次いで、PH値3.0〜5.0及び温度
10〜50℃の条件のもとで10〜120分間保持して熟
成し、更に上記アルカリ水溶液を加えると共に酸
素含有ガスを吹込んでγ−FeOOH生成反応を完
結させることを特徴とするレピツドクロサイトの
製造方法。1. Add an alkaline aqueous solution such as caustic alkali or ammonia to the ferrous chloride aqueous solution, and add 0.4 to 0.7 times the theoretical amount required to convert the ferrous chloride to ferrous hydroxide, and then blow in oxygen-containing gas. Seed crystals of γ-FeOOH are generated, then pH value 3.0-5.0 and temperature
Lepidocrocite, which is aged by being held for 10 to 120 minutes under conditions of 10 to 50°C, and further added with the above aqueous alkaline solution and blowing oxygen-containing gas to complete the γ-FeOOH production reaction. manufacturing method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20226785A JPS6265934A (en) | 1985-09-12 | 1985-09-12 | Production of lepidocrosite |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20226785A JPS6265934A (en) | 1985-09-12 | 1985-09-12 | Production of lepidocrosite |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6265934A JPS6265934A (en) | 1987-03-25 |
| JPH0255382B2 true JPH0255382B2 (en) | 1990-11-27 |
Family
ID=16454708
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20226785A Granted JPS6265934A (en) | 1985-09-12 | 1985-09-12 | Production of lepidocrosite |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6265934A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0547086Y2 (en) * | 1988-10-13 | 1993-12-10 | ||
| KR102328254B1 (en) * | 2017-11-08 | 2021-11-18 | 주식회사 엘지에너지솔루션 | Cathode for lithium-sulfur battery comprising maghemite, and lithium-sulfur battery comprising thereof |
-
1985
- 1985-09-12 JP JP20226785A patent/JPS6265934A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6265934A (en) | 1987-03-25 |
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