A Study on Synthesis of Synthetic Zeolites

Abstract

The synthesis of zeolites (molecular sieves) with a wide variety of engineered structures and properties requires profound theoretical and laboratory experiments. Recently, there is an increasing interest in the field of designing and preparation of synthetic zeolites in tree main directions (by treatment of natural zeolites, which preserves their initial crystalline structure; by natural clay minerals; and by conventional hydrothermal synthesis). An objective of this work is to review the current trends in zeolite synthesis as well as their structure and classification. Attention is given to the zeotite synthesis from industrial wastes, particularly from fly ash, and their role in solving environmental problems.

Zeolites are crystalline, micro porous, hydrated aluminosilicates that are built from an infinitely extending three dimensional network of [SiO4] 4- and [AlO4] 5- tetrahedra linked to each other by the sharing of oxygen atoms [1]. Generally, their structure can be considered as inorganic polymer built from tetrahedral TO4 units, where T is Si4+ or Al3+ ion.