The influence of gel properties on the kinetics of crystallization and particulate properties of MFI-type zeolites. I. The influence of time and temperature of gel ageing on the particulate properties of silicalite-1 microcrystals

被引：27

作者：

Cizmek, A

Subotica, B

Kralj, D

Babic-Ivancic, V

Tonejc, A

机构：

[1] Rudjer Boskovic Inst, Zagreb 10001, Croatia

[2] Univ Zagreb, Fac Sci, Dept Phys, Zagreb 10000, Croatia

来源：

MICROPOROUS MATERIALS | 1997年 / 12卷 / 4-6期

基金：

美国国家科学基金会;

关键词：

crystallization; gel ageing; morphology; nucleation; particulate properties; silicalite-1;

D O I：

10.1016/S0927-6513(97)00075-8

中图分类号：

O69 [应用化学];

学科分类号：

081704 ;

摘要：

The influence of time and temperature of ageing of the amorphous gel precursor (2.5Na(2)O-8TPABr-60SiO(2)-800H(2)O) on the particulate properties (particle size distribution, particle shape, number of particles) of silicalite-l synthesized at 170 degrees C were studied by different experimental methods such as X-ray diffractometry (XRD), differential thermogravimetric analysis (TGA), particle size analysis, FT infra-red spectroscopy and scanning-electron microscopy (SEM). In spite of negligible changes in the crystal morphology, ageing of the gel considerably affects the number and size of silicalite-l crystals in the crystalline end products. The observed effects were discussed in terms of the formation of specific ordered subunits between silicate species and TPA(+) ions (germ nuclei) and their role in the nucleation and crystal growth of silicalite-l crystals. (C) 1997 Elsevier Science B.V.

引用

页码：267 / 280

页数：14

共 50 条

[1] ZEOLITE CRYSTALLIZATION FROM HIGH-SILICA MONOCATONIC OR BICATIONIC ALKALI (LI, NA OR K) GELS IN PRESENCE AND IN ABSENCE OF TPA IONS [J].