摘要
用取代法和共聚法合成了一系列羟基镍铝交联蒙托土。(27)~Al-NMR,UV谱表明两种合成方法都可以得到具有Kessin结构的羟基镍铝柱。取代法合成的交联蒙托土具有均一的(001)面衍射(d_(001)约1.80nm),而共聚法的样品有两种羟基镍铝柱支撑着层间,分别在1.80nm和1.55nm附近产生复合(001)面衍射。用高温老化处理可改善交联蒙托土的热稳定性。经过处理的样品在700℃焙烧后仍可保持稳定,与不经处理的样品相比,热稳定性提高200℃以上。
A series of hydroxy-M-Al cross-linked montmorillonites (Ni-Al--CLM) were prepared by two new methods, i. e. substitution and copo-lymerization. According to the 27A1-NMR and UV spectra of the pillaring solution, it may suggest that the hydroxy-M-Al oligomer having the structure of Keggin can be prepared by these two methods. Ni-Al-CLM prepared by substitution method shows only one (001) peak with d(001) value of 1.80 nm. But for Ni-Al-CLM prepared by copolymeriza-tion, there are two (001) peaks with basal spacing of 1.80 nm and 1.55 nm. The heat treatment of the pillaring agents before cross-linking or after cross-linking reaction was first performed on Al-CLM and Ni-Al--CLM, the higher thermal stability of these clays was resulted as compared with the untreated samples.
关键词
交联
分子筛
蒙脱石
羟基镍铝
Cross-linked,montmorillonite,pillaring,basal spacing,clay
