镁皂石的水热合成与表征研究(英文)

Synthesis and Characterization of Magnesium-Saponite by Hydrothermal Way

采用优化的水热合成法 ,在 473K反应 2h合成了具有优良长程有序性的 2∶1型三八面体蒙皂石 (皂石 )。XRD分析表明合成产物具有典型的皂石层状结构。TEM测试发现 ,不同温度下合成的皂石具有类似的形态 ,但其层状片大小随着合成温度的提高而增大。不同温度 ( 4 2 3K ,473K ,5 2 3K ,5 73K)下水热合成实验结果表明 ,473K是合成具有良好层状有序结构皂石的临界温度。不同层电荷合成皂石对于活性染料 (MB)的等温吸附实验说明吸附过程包含离子交换和絮凝机理。相对于天然蒙脱石 ,合成皂石对于离子性染料具有更大的吸附容量和作用力。

According to an optimized hydrothermal synthesis method, trioctahedral smectite(magnesium-saponite) with good long range order was synthesized within 2h at 473K. The reflection peaks of XRD pattern confirmed the trioctahedral layer structure of the product. TEM results were in good agreement with that of saponite synthesized hydrothermally at higher reaction temperatures. According to the determinations of the products synthesized under different reaction temperatures(423K, 473K, 523K, 573K), 473K was found to be a temperature threshold within short reaction time in the synthesis of sapontie having high long range order. As to the adsorption of organic cationic dye(MB), the capability of saponites with different layer charges exhibited similar capability. However, the mechanism of this kind of adsorption in the remediation of ionic type pollutants involved flocculation and ion exchange. Compared with natural montmorillonite, the synthetic saponite showed higher adsorption capability and affinity to ionic dye.