Shen Y H
Department of Resources Engineering, National Cheng Kung University, Tainan, Taiwan, ROC.
Chemosphere. 2001 Aug;44(5):989-95. doi: 10.1016/s0045-6535(00)00564-6.
Due to hydrophilic environment at its surface, natural bentonite is an ineffective sorbent for nonpolar nonionic organic compounds in water even though it has high surface area. The surface properties of natural bentonite can be greatly modified by simple ion-exchange reactions with large organic cations (cationic surfactants) and this organobentonite is highly effective in removing nonionic organic compounds from water. Cationic surfactant derived organobentonites have been investigated extensively for a wide variety of environmental applications. In this study, the preparation of organobentonite using nonionic surfactants has been investigated for the first time. Results indicate that nonionic surfactants intercalates into the interlamellar space of bentonite and may demonstrate higher sorption capacity than cationic surfactant. It is possible to create large interlayer spacing and high organic carbon content organobentonite by use of nonionic surfactants with suitable balance between the hydrocarbon and ethylene oxide chain lengths. In addition, nonionic surfactant derived organobentonites are more chemically stable than cationic surfactant derived organobentonites.
由于天然膨润土表面具有亲水性环境，尽管其比表面积高，但对于水中的非极性非离子有机化合物而言却是一种无效的吸附剂。通过与大型有机阳离子（阳离子表面活性剂）进行简单的离子交换反应，天然膨润土的表面性质可得到极大改性，这种有机膨润土在从水中去除非离子有机化合物方面非常有效。阳离子表面活性剂衍生的有机膨润土已针对各种环境应用进行了广泛研究。在本研究中，首次对使用非离子表面活性剂制备有机膨润土进行了研究。结果表明，非离子表面活性剂可插入膨润土的层间空间，并且可能表现出比阳离子表面活性剂更高的吸附容量。通过使用在烃链和环氧乙烷链长度之间具有适当平衡的非离子表面活性剂，有可能制备出具有大层间距和高有机碳含量的有机膨润土。此外，非离子表面活性剂衍生的有机膨润土比阳离子表面活性剂衍生的有机膨润土在化学上更稳定。
