作者：SHAOWEI ZHANG;WANBING CHEN;ZHOUFU WANG;

作者单位：Department of Engineering Materials, University of Sheffield, Sheffield S1 3JD, UK.

刊名：Journal of the Technical Association of Refractories

ISSN：0285-0028

出版年：2007-01-05

卷：27

期：3

起页：175

止页：179

分类号：TQ175

语种：英文

关键词：Molten salt synthesis;mechanism;alkali metal chloride;spinel;refractories;

内容简介

Magnesium aluminate (MA) spinel powders were synthesised in LiCl, NaCl and KC1 melts respectively using industrial alumina and lightly-calcined magnesia as raw materials. The effects of firing temperature, time and salt type on extents of reaction were investigated and the corresponding reaction mechanisms discussed. MA powders could be synthesised in LiCl after 3h at 800 deg C or 5h at 700 deg C. These synthesis temperatures are 600-700 deg C lower than that (>1400 deg C) required by the conventional solid-solid reaction route Apart from LiCl, KCl and NaCl showed great accelerating-effects on the MA formation, although they were less effective than LiCl. When they were used as reaction media, the synthesis temperature of MA was reduced to about 950 deg C. The "dissolution-precipitation" mechanism played an important role in molten salt synthesis of MA, although the "template-growth" mechanism was also to some extents involved.