摘要
云母-蒙脱土的骨架振动光谱不同于蒙脱土,在相应的位置,云母-蒙脱土的振动谱峰都是双蜂。利用凝胶分散法制备的硅交联蒙脱土,硅交联云母-蒙脱土及铝交联云母-蒙脱土,经450~500℃焙烧后,在1000~1200cm^(-1)和400~500cm^(-1)区间内相应于四面体的Si—O反对称伸缩及弯曲振动部分谱峰发生了高波数位移;而交联剂、粘土及未焙烧的层柱分子筛都不发生此现象。这表明只有经过高温焙烧后,交联剂与粘土才发生明显的化学作用,使四面体层结构重排。这对于交联机理的研究提供了依据。
The pillared clays including silica pillared montmorillomte (Si-CLM), silica pillared rectorite (Si-CLR) and alumina pillared rectorite(Al-CLR)were prepared by our new metho-gel dispersion method. The IRframework vibration spectra of 1000-1200 and 400-500cm-1 stem from tetrahedral antisymmetric stretching and Si-O bending vibration modes respectively. Compared with one vibration spectrum of montmorillonite, there are two vibration spectra of rectorite at the corresponding position. After calcination at 450--500℃ for 2 h, some spectra of pillared ciays shift to the higher frequency (CLR: A-47 cm-1; CLM. A = 14 cm-1), but under the same treatment conditions,the tetrahedral antisymmetric stre- tching vibration spectra of clays and pillaring agents remain unchanged, and the spectra of uncalcined pillared clays are similar to those of clays. This shows that after calcination there is a kind of chemical action between pillaring agent and clay. A pillaring mechanism is suggested that after calcination some tetrahedral silicon or aluminium reverse to gallery and react with pillaring agents whether or not there exists tetrahedral aluminium substitution in clays.
基金
国家自然科学基金
中国石油化工总公司科研基金