物理化学学报 >> 1993, Vol. 9 >> Issue (04): 455-460.doi: 10.3866/PKU.WHXB19930407

研究论文 上一篇    下一篇

部份层无序铝交联蒙脱土结构的研究

项斯芬; 李红; 王连波; 蒋青; 张婉静; 林炳雄   

  1. 北京大学化学系,北京 100871
  • 收稿日期:1992-02-25 修回日期:1992-04-13 发布日期:1993-08-15
  • 通讯作者: 项斯芬

Structural Study on Partially Disordered Layer Lattice of Polyoxyaluminum Pillared Montmorillonite

Xiang Si-Fen; Li Hong; Wang Lian-Bo; Jiang Qing; Zhang Wan-Jing; Lin Bing-Xiong   

  1. Department of Chemistry, Peking University, Beijing 100871
  • Received:1992-02-25 Revised:1992-04-13 Published:1993-08-15
  • Contact: Xiang Si-Fen

摘要: 应用非完整晶体的XRD衍射及阳离子交换量的测定等实验数据, 得出了铝交联蒙脱土的三维结构模型. 结构中Al(III)多数以十三聚体形式进入层间, 层间距为1.97 nm, 几率为0.65, 少数以六聚体形式进入层间, 层间距为1.5 nm, 几率为0.25, 其余10%的层间仅为水分子. 并给出了交联柱子在层间的分布与层单元之间的连接方式. 目前通用的以Bragg公式计算所得的d_(001)值来表征交联浆脱土的层间距是不确切的.

关键词: 蒙脱土, 羟基铝, 部份层无序, 结构模型

Abstract: The structure of pillared montmorillonite is partially disordered layer lattice. Its basal spacings can be expanded to many possible values with different probabili-ties depending on the type and structure of the pillars or the preparation conditions. If a formula describing the X-ray diffraction intensity of partially disordered layer lattice as a function of basal spacings and corresponding probabilities is computa-tionally simulated with the experimental XRD pattern, the basal spacings and prob-abilities can thus be obtained. In this work, two of the polyoxyaluminum pillared montmorillonite samples with Al_(13) as main pillars were prepared. The simulated results show that most of the basal spacings are expanded to 1.97 nm with a probability of 0.65 corresponding to Al_(13) as pillars; some of the basal spacings are 1.5 nm with a probability of 0.25 corresponding to Al_6 as the most possible pillaring species; the rest ones are 1.1 nm containing water molecules only in the interlamellar region. The experimental results obtained from CEC, ICP etc. are used to calculate the distribution of the pillars in the interlayer zone. Subsequently, a three-dimensional structural model is built up. The agreement of the pore-volume between theoretical calculation and experimental result verifies the rationality of the structural model. Therefore, the basal spacing usually characterized by d_(001) which is calculated from Bragg equation actually is not exact.

Key words: Montmorillonite, Polyoxyaluminum, Partially dissordered layer lattice, Structural model