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›› 2006, Vol. 6 ›› Issue (2): 205-209.

• 过程与工艺 • 上一篇    下一篇

高膨胀率高质量蛭石粉体研制 -I. 热膨胀机理初探

胡光锁,朱永平,李政一,张伟刚   

  1. 北京工商大学化学与环境工程学院
  • 出版日期:2006-04-20 发布日期:2006-04-20

Preparation of Vermiculite Powder with High Expansion and High Quality-I. Primary Study on the Expansion Mechanism

HU Guang-suo,ZHU Yong-ping,LI Zheng-yi,ZHANG Wei-gang   

  1. College of Chemical and Environmental Engineering, Beijing Technology and Business University
  • Online:2006-04-20 Published:2006-04-20

摘要: 利用高温X射线衍射和热重-差热分析技术对蛭石在加热过程中膨胀及相应的结构变化进行了研究. 与XRD谱图相联系,结合蛭石的颜色与膨胀率进行统计分析,将蛭石矿物分为黄色蛭石、深黄色蛭石和深绿色蛭石,发现在相同加热条件下其水化程度和膨胀率之间存在确定的关系,同时又表现出不同的微观结构特征. 在膨胀机理研究的基础上,进一步分析了不同蛭石在不同温度下的膨胀率与结构变化的规律,得出了层间水是影响蛭石体积膨胀率的主要因素,结构水的脱出则主要引起层间距离的变化,这为加工生产高膨胀率、高质量的蛭石提供了重要的依据.

关键词: 蛭石, 加热, 膨胀, XRD, 热重-差热分析, 机理

Abstract: The expansion mechanism of vermiculite was characterized during heating-up with in-situ X-ray diffraction and TG-DSC analysis. Combining X-ray diffractions with their inherent colors and volumetric expansion ratios, vermiculite is statistically classified into three categories, yellow, deep-yellow and deep-green ones, based on its thermal behavior in the hydration process. Certain correlations are found existing between the hydration process and volumetric expansion ratio at certain heating conditions. Different microcosmic characters are detected with the three types of vermiculite. Combining the analyzing of structural change, volumetric expansion ratio and content of different types of water releasing during heating at various temperatures, the mechanism of volumetric expansion is discussed primarily, which provides some very useful indications for production of vermiculite powder with high expansion and high quality.

Key words: vermiculite, heating, expansion, XRD, TG-DSC, mechanism