吉林露水河硅藻土在煅烧中的结构及性能的变化

Structural and Characteristic Changes of Diatomite in Calcination from Lushuihe of Jilin

应用X射线衍射、红外光谱分析、扫描电镜及化学分析方法对吉林露水河硅藻土在煅烧中的结构及性能的变化进行研究,结果表明:高温时蛋白石转变成方英石,激烈的相变温度为1160℃左右;当温度在1100℃～1200℃时,硅藻的微孔开始阻塞或消失,并出现开裂现象,硅藻的结构变得模糊,但硅藻仍保持其外形;室温～600℃,比表面积逐渐增加,600℃～1200℃比表面积则减少;室温～700℃时,pH值逐渐减小,700℃～1200℃时,pH值则逐渐增加。

Characteristic and structural changes of diatomite from Lushuihe in calcination are studied with X--ray diffraction, infra--red spectrometry, SEM technique and chemical analyses. The results of the study indicate that: opal becomes cristobalinte at high temperature (about 1 100℃); temperature of intense phase transition is about a(c)1 160℃. At 1 100℃1 200℃ in temperature, small holes of diatomite begin to be blocked or disappear. The structure of diatomite is not clear, but it keeps its old appearence. At the temperature of 25℃600℃, surface to volume ratio goes upward; while at the temperature ranging from 600℃ to 1 200℃, the surface to volume ratio goes downward. At the temperature ranging 25℃700℃, the pH comes down; and at the temperature of 700℃1 200℃, the pH keeps raising.