FTIR investigation of CTAB-Al-montmorillonite complexes

被引:141
作者
Xue, Weihong
He, Hongping [1 ]
Zhu, Jianxi
Yuan, Peng
机构
[1] Chinese Acad Sci, Guangzhou Inst Geochem, Guangzhou 510640, Peoples R China
[2] Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China
基金
中国国家自然科学基金;
关键词
FTIR spectrum; sorbed water; surfactant; hydroxy-Al cations; CTAB-Al-montmorillonite complexes;
D O I
10.1016/j.saa.2006.09.024
中图分类号
O433 [光谱学];
学科分类号
0703 ; 070302 ;
摘要
In this study, CTAB-Al-montmorillonite complexes were synthesized by pre-modifying montmorillonite using different concentrations of surfactant (resulting in different surfactant loadings and basal spacings), then pillaring the organoclays with hydroxy-Al cations. The resultant inorganic-organic montmorillonite complexes were characterized using FTIR, with a combination of XRD, TG and chemical analysis. This study indicates that the basal spacings of the CTAB-Al-montmorillonite complexes and the amounts of Al-contained pillars strongly depend on the surfactant loadings in the clay interlayer space, resulted from the mobility variation of the intercalated surfactants. During pillaring hydroxy-Al cations into clay interlayer space, part of the intercalated surfactants were removed, resulting in a decrease of the ordering of alkyl chains and the frequency shifts of Si(Al)-O, Si-O-Al and (M-O)(Td) stretching vibrations. The hydrophobicity of the CTAB-Al-montmorillonite complex also strongly depends on the surfactant loading whereas that of the CTAB-Al-montmorillonite complex is relative lower than that of the corresponding organoclay, indicated by the frequency shift of the vibrations corresponding to the sorbed water and their contents estimated by TG curves. With the decrease of the sorbed water content, the frequency of the band of H-O-H bending (v(2)) shifts to higher frequency while the O-H stretching vibration (v(1) and v(3)) shifts to lower frequency, indicating that H2O is less hydrogen bonded. Meanwhile, the ordered conformations of the alkyl chains in CTAB-Al-montmorillonite complex decrease when compared with that of the corresponding organoclay. (C) 2006 Elsevier B.V. All rights reserved.
引用
收藏
页码:1030 / 1036
页数:7
相关论文
共 36 条