Anomalous crystallization mechanism in the synthesis of nanocrystalline ZSM-5

被引：253

作者：

Van Grieken, R ^{[1
]}

Sotelo, JL ^{[1
]}

Menéndez, JM ^{[1
]}

Melero, JA ^{[1
]}

机构：

[1] Univ Complutense Madrid, Fac Chem, Dept Chem Engn, E-28040 Madrid, Spain

来源：

MICROPOROUS AND MESOPOROUS MATERIALS | 2000年 / 39卷 / 1-2期

基金：

欧盟地平线“2020”;

关键词：

nanocrystalline; ZSM-5; zeolite; crystallization mechanism;

D O I：

10.1016/S1387-1811(00)00190-6

中图分类号：

O69 [应用化学];

学科分类号：

081704 ;

摘要：

Nanocrystalline ZSM-5 (crystal size in the range 10-100 nm) has been synthesized in only 24 h by hydrothermal crystallization of clear supersaturated homogeneous synthesis mixtures. The influence of the aluminum source, aging time, pH, water content and presence of alkaline cations on the properties of the final nanocrystalline zeolite have been studied. Samples with different degrees of crystallinity have been prepared and characterized by X-ray fluorescence, X-ray diffraction, solid state MAS-NMR, transmission electron microscopy and nitrogen adsorption (BET) in order to investigate the crystallization mechanism. The process involves the formation of an initial amorphous solid prior to the zeolite crystallization, which is gradually transformed into nanocrystalline ZSM-5 through solid-solid transformations. Additionally, the conventional formation of ZSM-5 from crystalline nuclei generated in the remaining liquid solution is observed after 48 h. (C) 2000 Elsevier Science B.V. All rights reserved.

引用

页码：135 / 147

页数：13

共 31 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].

AIELLO, R ;

CREA, F ;

NASTRO, A ;

PELLEGRINO, C .

ZEOLITES, 1987, 7 (06) :549-553

[2]

Argauer R.J., 1972, US Pat., Patent No. [3702886, US3702886A]

[3]

CHEN NY, 1988, CHEM ENG PROG, V84, P32

[4] 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 [J].

Cizmek, A ;

Subotica, B ;

Kralj, D ;

Babic-Ivancic, V ;

Tonejc, A .

MICROPOROUS MATERIALS, 1997, 12 (4-6) :267-280

[5]

CUNDY CS, 1993, FARADAY DISCUSS, V95, P235

[6] STRUCTURAL RECOGNITION AND PREORGANIZATION IN ZEOLITE CATALYSIS - DIRECT AROMATIZATION OF NORMAL-HEXANE ON ZEOLITE L-BASED CATALYSTS [J].

DEROUANE, EG ;

VANDERVEKEN, DJ .

APPLIED CATALYSIS, 1988, 45 (01) :L15-L22

[7] DIFFUSION OF ALKANES IN MOLECULAR-SIEVES - EVIDENCE FOR CONFINEMENT EFFECTS [J].

DEROUANE, EG ;

NAGY, JB ;

FERNANDEZ, C ;

GABELICA, Z ;

LAURENT, E ;

MALJEAN, P .

APPLIED CATALYSIS, 1988, 40 (1-2) :L1-L10

[8] SHAPE SELECTIVITY IN CATALYSIS BY ZEOLITES - THE NEST EFFECT [J].

DEROUANE, EG .

JOURNAL OF CATALYSIS, 1986, 100 (02) :541-544

[9] ROLE OF SELECTED SYNTHESIS VARIABLES IN NUCLEATION AND GROWTH OF ZEOLITE ZSM-5 [J].

DEROUANE, EG ;

GABELICA, Z .

JOURNAL OF SOLID STATE CHEMISTRY, 1986, 64 (03) :296-304

[10]

ENGELHARDT G, 1987, HIGH RESOLUTION SOLI, P106

← 1 2 3 4 →