Continuous production of hybrid metal oxide fine particles

复合金属氧化物细颗粒的连续生产

• 批准号: 06555230
• 负责人: ARAI Kunio
• 金额: $ 6.27万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06555230/
• 关键词: Supercritical Water; Reaction Crystallization; Fine Particle; hybrid metal oxide fine particles; Barium Hexaferrite; バリウムフェライト; 反応晶折; 脱水反応

The synthesis of hybrid metal oxide fine particles in supercritical wate (SCW) were investigated by using a flow apparatus. The sample used was a barium hexaferrite, which is expected as a high density recording material.It was revealed from the experiments that the present technique with SCW can produce fine particles of barium hexaferrite continuously within a very short period under certain reaction conditions and that the size and shape of the product particles are strongly dependents on the temperature and pressure. For producing the fine particles (less than 60 nm) of narrow size distributions, it should be noted that the solution is firstly prepared via neutralization of Fe (NO_3) _2Ba (No3) 2 aqueous solutions and KOH and then the rate of the nucleation and crystal growth stages has to be controlled. The nucleation rate can be controlled by changing the heating rate. The conditions for successful producing particles through this work were the initial heating at 280 C for nucleation and 400 C for crystal growth at fairly high Barium concentrations. It was also suggested that the applicable range of this technique is very wide in concentration range, metal species, temperature and pressure and can be an industrial process.

利用流动装置研究了超临界水中杂化金属氧化物微粒的合成。所用样品是有望作为高密度记录材料的Ba6铁氧体，实验表明，目前的SCW技术在一定的反应条件下可以在很短的时间内连续生产Ba6铁氧体微粒，产物微粒的大小和形状强烈依赖于温度和压力。要得到粒径分布较窄的细小颗粒(小于60 nm)，首先要通过Fe(NO3)2BA(NO3)2水溶液和KOH的中和来制备溶液，然后控制成核和晶体生长阶段的速度。可以通过改变加热速度来控制形核速度。通过这项工作成功地产生粒子的条件是初始加热280℃成核和400℃在相当高的Ba2+浓度下生长晶体。该技术在浓度范围、金属种类、温度和压力等方面的适用范围都很广，可以工业化生产。

项目成果

新井邦夫,阿尻雅文: "超臨界水中での反応晶析" ケミカルエンジニアリング. 39. 9-13 (1994)

Kunio Arai，Masafumi Ajiri：“超临界水中的反应结晶”化学工程 39. 9-13 (1994)。

T.Adschiri,K.Arai: "“Hydrothermal Synthesis of Metal Oxide Fine Particles in Supercritical Water"" Proc.Int.Symp.Supercrical Fluids. 241-246 (1994)

T.Adschiri、K.Arai：“超临界水中金属氧化物细颗粒的水热合成”，Proc.Int.Symp.超临界流体 241-246 (1994)