Effect of Carbonate Ion in Colloidal Mother Liquid on Formation of Acicular .ALPHA.-FeOOH Particles.

• Iwasaki Kazuharu

  Sendai Technology Center, Sony Corporation

• Yamamura Tsutomu

  Department of Metallurgy, Graduate School of Engineering, Tohoku University

Bibliographic Information

Other Title

• 針状α‐ＦｅＯＯＨ粒子の生成に及ぼすコロイド母液の炭酸イオンの影響
• シンジョウ アルファーFeOOH リュウシ ノ セイセイ ニ オヨボス コロイド ボエキ ノ タンサン イオン ノ エイキョウ

Abstract

The relationship between rate constant, activation energy for formation of acicular α-FeOOH particles and addition quantity of CO₃^2- to colloidal mother liquid was discussed under the conditions: the pH and FeCl₃ concentration of mother liquid are constant 12.0-12.1 and 0.040-0.044 kmol/m₃ respectively. The rate constant decreased with increasing addition quantity of CO₃^2-upto 0.25kmol/m₃, and was constant over 0.25 kmol/m³ for the aging at 80°C. At the temperature lower than 55°C, it did not show the dependence on CO₃^2- concentration. Similarly, the activation energy decreased with increasing addition quantity of Co₃^2-upto 0.25 kmol/m³, and further addition did not affect the activation energy. The observed dependence of the rate constant on the addition quantity of CO₃^2-can be attributed to the following reason: the crystal growth of α-FeOOH is restrained by the adsorption of CO₃^2- on the specified crystal plane. The fact that activation energy decreases with increasing addition quantity of CO₃^2- indicates that recrystallization process of Fe(OH)₄^- changes from the surface reaction controlled process to the diffusion controlled process. Both crystallite size and median diameter of acicular, α-FeOOH particles decreased with increasing addition quantity of CO₃^2-. Both lengths of major axis and minor axis of acicular particles similarly decreased with increasing addition quantity of CO₃2^-. These dependencies indicate that the CO₃^2- ions adsorb on the crystal planes homogeneously without any preference of the crystal planes among a, b, and c planes. This resulted in the decrease of dimension of the acicular α-FeOOH formed with similar aspect ratio.

Journal

• Journal of the Japan Society of Powder and Powder Metallurgy

  Journal of the Japan Society of Powder and Powder Metallurgy 46 (3), 247-251, 1999

  Japan Society of Powder and Powder Metallurgy

Keywords

• amorphous ferric oxyhydroxide
• acicular α-FeOOH particle
• rate constant
• activation energy
• crystallite size

Details

• CRID: 1390282681285346432
• NII Article ID: 10002262012
• NII Book ID: AN00222724
• DOI: 10.2497/jjspm.46.247
• COI: 1:CAS:528:DyaK1MXislOqt7Y%3D
• ISSN: 18809014
• ISSN: 05328799
• ISSN: http://id.crossref.org/issn/05328799
• NDL BIB ID: 4690179
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I4690179
• Text Lang: ja
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed