Croatica Chemica Acta, Vol. 72 No. 2-3, 1999.
Review article
Recent Developments in Zeolite-like Materials Synthesis and Characterisation
Nataša Zabukovec Logar
; National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
Ljubo Golič
; University of Ljubljana, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
Venčeslav Kaučič
; National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
Abstract
In the last few years considerable effort has been directed at the targeted synthesis of zeolites and zeolite-like microporous materials with predetermined physical and catalytic properties. With new computational techniques, it has become possible to design templates for the synthesis of specific microporous structures with desired pore siže and connectivities. With regard to zeolite-like materials, much attention has been focused on transition metal containing systems, like zincosilicates, titanosilicates and various metalloaluminophosphates with a potential to generate specific redox conditions, in addition to Br0nsted and Lewis active catalytic centres. Experimental determination of subtle structural features such as the nature and position of the catalytically active metal sites, and the location, orientation and disorder of templates, metals or complexes within the microporous hosts has become possible using new characterisation techniques, mostly based on X-ray diffraction and the use of synchrotron and neutron radiation sources.
In situ studies of the kinetics of nucleation, crystal growth and phase transitions or catalyst activation and operation at elevated temperatures have remarkably benefited from the new high-flux and well-collimated third-generation synchrotron radiation sources, and from the advances in the X-ray detector design and data handling.
Keywords
zeolites; aluminophosphates; zincophosphates; molecular sieves; microporous materials; X-ray diffraction; synchrotron radiation
Hrčak ID:
132156
URI
Publication date:
1.9.1999.
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