高温处理对钠化膨润土蒙脱石结构变化的影响

The effect of high temperature treatment on the structure of sodium bentonite montmorillonite

摘要:

以安徽芜湖（WH）、四川三台（ST）和河南信阳（XY）三个地区的膨润土为原料，以碳酸钠为钠化剂分别对三种原料进行钠化改性处理，获得钠化膨润土样品WH-G、XY-G和ST-G，随后对钠化后样品进行高温热处理. 对原样、钠化样品及热处理样品的物相、结构、热学属性及谱学特征进行了表征分析. 结果表明，WH-G、XY-G和ST-G三个样品中蒙脱石失去吸附水和层间水的温度随着样品中蒙脱石的层电荷的增加呈上升趋势，但膨润土的热稳定性却与之相反. WH-G和XY-G样品在处理温度900 °C时蒙脱石的结构完全被破坏，而ST-G样品在800 °C时蒙脱石的结构即完全被破坏.

Abstract:

The bentonite from Wuhu, Anhui (WH), Santai, Sichuan (ST), and Xinyang, Henan (XY) were used as the raw material, and sodium carbonate was used as a modifying agent to modify three raw materials (named as WH-G, XY-G and ST-G), then the sodium samples were heat-treated at high temperature. The phase, structure, thermal properties and spectral characteristics of samples were characterized and analyzed. The results showed that the temperature of the montmorillonite losing adsorbed water and interlayer water in the three samples WH-G, XY-G and ST-G increase with the increase of the layer charge number of the montmorillonite in the samples, but its thermal stability is opposite. The structures of montmorillonite WH-G and XY-G samples are completely destroyed at 900 °C, while the structure of montmorillonite of ST-G sample is completely destroyed at 800 °C.