关键词: 柱撑黏土, 核磁共振, 漫反射红外光谱, 孔结构

Abstract:

Pillared clays（Ti-PILCs）were synthesized from Na-type montmorillonite through intercalation with polymeric hydroxy-titanium.The mechanism of the pillaring course was studied by means of magic angle spinning nuclear magnetic resonance（MAS NMR）and diffuse reflectance infrared spectroscopy（DRIFTS）techniques.DRIFTS suggested that after Ti-pillaring，the silicon-oxygen tetrahedral Si—O—Si bond and aluminum oxide octahedral Si—O—Al bond were broken.Meanwhile，NMR also showed the change of the silicon-oxygen tetrahedral structure and aluminum oxide octahedral structure in the pillared clay.In the pillaring process，the titanium hydroxy-oligomeric cations entered the layers of the montmorillonite by ion-exchange，the Si—O—Al bond of the raw clays were broken，the silicon-oxygen tetrahedron structure were overturned，and the reactive oxygen species（structural hydroxyl）reacted with titanium hydroxy-oligomeric cations to form Si—O—M bond.This led to the incorporation of pillaring species of Ti in the layers of the clay.After further heat treatment，the TiO₂ pillars were formed in the layers to obtain Ti-PILCs.

Key words: 柱撑黏土, 核磁共振, 漫反射红外光谱, 孔结构