KR960022263A - How to make lepidocrocite - Google Patents

How to make lepidocrocite Download PDF

Info

Publication number
KR960022263A
KR960022263A KR1019940035212A KR19940035212A KR960022263A KR 960022263 A KR960022263 A KR 960022263A KR 1019940035212 A KR1019940035212 A KR 1019940035212A KR 19940035212 A KR19940035212 A KR 19940035212A KR 960022263 A KR960022263 A KR 960022263A
Authority
KR
South Korea
Prior art keywords
reaction
crystal growth
repidocrosite
rate
seed crystal
Prior art date
Application number
KR1019940035212A
Other languages
Korean (ko)
Other versions
KR0136196B1 (en
Inventor
김대영
손진군
김병원
한기현
Original Assignee
김만제
포항종합제철 주식회사
신창식
재단법인 산업과학기술연구소
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 김만제, 포항종합제철 주식회사, 신창식, 재단법인 산업과학기술연구소 filed Critical 김만제
Priority to KR1019940035212A priority Critical patent/KR0136196B1/en
Publication of KR960022263A publication Critical patent/KR960022263A/en
Application granted granted Critical
Publication of KR0136196B1 publication Critical patent/KR0136196B1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G49/00—Compounds of iron
    • C01G49/02—Oxides; Hydroxides
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/10—Particle morphology extending in one dimension, e.g. needle-like

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Compounds Of Iron (AREA)
  • Hard Magnetic Materials (AREA)

Abstract

본 발명은 오디오, 비디오등 자기기록매체용 자성산화철 제조에 출발물질로 사용되는 침상성 레피도크로사이트(γ-FeOOH) 제조방법에 관한 것으로, 본 발명에 의하면, 염화제 1철 수용액에 NaOH 및 NH,OH등의 알칼리를 당량이하로 첨가하여 수산화 제1철을 제조한 후, 이를 산화시켜 레피도크로사이트 종결정을 합성한 후 결정성장반응을 진행시키는 습식산화방법에 의한 레피도크로사이트 제조방법에 있어서, 레피도크로사이트 종결정 생성반응에서의 PH 조절속도가 0.2-0.8pH/min으로, 결정 성장 반응의 전반에서는 pH증가속도를 0.015-0.025pH/min로, 결정성장반응의 후반에서는 pH증가속도를 0.015-0.020pH/min로 조절한다.The present invention relates to a method for producing acicular repidocrosite (γ-FeOOH), which is used as a starting material for producing magnetic iron oxide for magnetic recording media such as audio and video. Preparation of ferrous hydroxide by adding alkali, such as NH and OH, to the equivalent, and then oxidizing it to synthesize repidocrosite seed crystals, and then preparing repidocrosite by a wet oxidation method in which a crystal growth reaction proceeds. In the method, the pH control rate in the redodocrocite seed crystal formation reaction was 0.2-0.8 pH / min, the pH increase rate was 0.015-0.025 pH / min in the first half of the crystal growth reaction, and in the second half of the crystal growth reaction. The pH increase rate is adjusted to 0.015-0.020 pH / min.

상기 방법으로 제조된 레피도크로사이트에는 괴타이트 및 아카가나이트등이 혼입되지 않으며, 침상성이 좋고, 표면이 균일하다.The lepidocrocite produced by the above method does not contain goatite, acaganite, or the like, has good acicularity, and has a uniform surface.

Description

레피도크로사이트 제조방법How to make lepidocrocite

본 내용은 요부공개 건이므로 전문내용을 수록하지 않았음As this is a public information case, the full text was not included.

제1도의(가)는 본 발명의 실시예1중 비교예1의 조건으로 제조된 입자의 TEM사진(나)는 본 발명의 실시예 1중 발명예2의 조건으로 제조된 입자의 TEM 사진(다)는 본 발명의 실시예1중 비교예2의 조건으로 제조된 입자의 TEM 사진.1A is a TEM photograph of the particles prepared under the conditions of Comparative Example 1 of Example 1 of the present invention (B) is a TEM photograph of the particles prepared under the conditions of Inventive Example 2 of Example 1 of the present invention ( C) TEM picture of the particles prepared under the conditions of Comparative Example 2 of Example 1 of the present invention.

Claims (1)

염화 제1철 수용액에 알칼리 수용액을 당량이하로 첨가하여 수산화제 1철을 제조한 다음 이를 산화시켜 레피도크로사이트 종결정을 제조한 후, 그 종결정를 성장시켜 레피도크로사이트를 제조하는 습식산화방법에 있어서, 염화 제1철 수용액에 NaOH 및 NH40H와 같은 알칼리 수용액을 당량이하로 첨가하여 수산화 제1철을제조한 후, 이를 산화시켜 레피도크로사이트 종결정을 제조하되, 반응현탁액의 PH를 반응시작과 동시에 pH6-7로부터 PH3-3.8까지 0.2-0.8pH/min 속도로 변화시키는 종결정 제조단계; 상기 반응 현탁액의 온도를 일정온도로 승온한 다음 산화반응을 진행시켜 결정을 성장시키되, pH를 반응시작과 동시에 pH4부터 시작하여 pH4.5의 값까지 0.015-0.025pH/min속도로 중대시키는 제1단계 결정성장 반응단계; 및 상기 제1단계 결정성장단계 후 산화반응을 진행시켜 결정을 성장시키되 pH물 반응시작과 동시에 pH3.5로부터 시작하여 pH5.5까지 0.015-0.02pH/min 속도로 증대시키고, pH가 5.5되는 시점에서 반응을 종결시키는 제2단계 결정성장 반응단계를 포함함을 특징으로 하는 레피도로크로사이트 제조방법.Ferric chloride was added to the aqueous solution of ferrous chloride in an equivalent amount to produce ferrous hydroxide, and then oxidized to prepare a lepidocrocite seed crystal, and the seed crystal was grown to produce wetpicrosite. In the method, ferric chloride is prepared by adding an aqueous alkali solution such as NaOH and NH 4 0H to the ferrous chloride solution in an equivalent amount or less, and then oxidizing to prepare a lepidocrocite seed crystal. Seed crystal preparation step of changing the pH at the rate of 0.2-0.8pH / min from pH 6-7 to PH3-3.8 at the same time as the reaction starts; After raising the temperature of the reaction suspension to a constant temperature and proceeding the oxidation reaction to grow crystals, the first to start the pH from the pH4 to the value of pH4.5 at the rate of 0.015-0.025pH / min at the same time the reaction starts Crystal growth reaction step; And after the first step of the crystal growth step is subjected to the oxidation reaction to grow the crystals, but at the same time the pH water reaction starts from pH3.5 to pH5.5 to 0.015-0.02pH / min to increase the rate, the pH is 5.5 Repidocrosite production method characterized in that it comprises a second step crystal growth reaction step of terminating the reaction in. ※ 참고사항:최초출원 내용에 의하여 공개하는 것임.※ Note: The disclosure is based on the initial application.
KR1019940035212A 1994-12-20 1994-12-20 Manufacturing method of lepidocrocite KR0136196B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1019940035212A KR0136196B1 (en) 1994-12-20 1994-12-20 Manufacturing method of lepidocrocite

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1019940035212A KR0136196B1 (en) 1994-12-20 1994-12-20 Manufacturing method of lepidocrocite

Publications (2)

Publication Number Publication Date
KR960022263A true KR960022263A (en) 1996-07-18
KR0136196B1 KR0136196B1 (en) 1998-04-25

Family

ID=19402330

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1019940035212A KR0136196B1 (en) 1994-12-20 1994-12-20 Manufacturing method of lepidocrocite

Country Status (1)

Country Link
KR (1) KR0136196B1 (en)

Also Published As

Publication number Publication date
KR0136196B1 (en) 1998-04-25

Similar Documents

Publication Publication Date Title
US3947502A (en) Production of finely divided acicular magnetic iron oxides
US3931025A (en) Magnetic iron oxides with improved orientability and a process for their production
US4202871A (en) Production of acicular ferric oxide
US4729846A (en) Method for manufacturing lepidocrocite
US4176172A (en) Particle gamma ferric oxide
US3843773A (en) Process for producing fine acicular gamma ferric oxide crystals
US4122216A (en) Ferro-magnetic acicular particles for recording medium and process for preparing the same
US4597958A (en) Method of producing hydrated iron oxide
KR960022263A (en) How to make lepidocrocite
CA1158837A (en) Method of preparing gamma ferric hydroxyoxide powder
US4224175A (en) Process for the preparation of magnetic powders based on γ-Fe2 O3
KR100270077B1 (en) A method of preparing repidocrocite
US4201761A (en) Process for making iron oxide of controlled particle size
US4086174A (en) Cobalt modified acicular γ ferric oxide and process for preparing the same
US4560544A (en) Process for the preparation of acicular α-FeOOH for magnetic recording materials
EP0857693A1 (en) Processes for producing hydrated iron oxide and ferromagnetic iron oxide
JPS6251895B2 (en)
US4495164A (en) Process for producing acicular magnetite or acicular maghemite
JPH0948619A (en) Preparation of goethite particle
US4748017A (en) Method for manufacturing lepidocrocite
JPS62119117A (en) Production of lepidocrocite
KR950017741A (en) Method for Preparing Lepidodo Crocite
SU1164792A1 (en) Magnetic powder material for working layer of magnetic record medium
JPH0259431A (en) Production of iron oxyhydroxide
JPH033612B2 (en)

Legal Events

Date Code Title Description
A201 Request for examination
E701 Decision to grant or registration of patent right
GRNT Written decision to grant
FPAY Annual fee payment

Payment date: 20021218

Year of fee payment: 6

LAPS Lapse due to unpaid annual fee