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.

采用流动合成装置研究了超临界水（SCW）中混合金属氧化物微粒的合成。实验结果表明，在一定的反应条件下，利用超临界水技术可以在很短的时间内连续地制备出钡铁氧体的微细颗粒，而且产物颗粒的大小和形状强烈地依赖于温度和压力。为了制备窄粒度分布的细颗粒（小于60 nm），应注意的是，首先通过Fe（NO_3）_2Ba（NO_3）_2水溶液和KOH的中和来制备溶液，然后必须控制成核和晶体生长阶段的速率。形核速率可以通过改变加热速率来控制。通过这项工作成功生产颗粒的条件是在280 ℃下进行成核的初始加热和在相当高的钡浓度下进行晶体生长的400 ℃。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较广，可实现工业化生产。

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)