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Synthesis of Zeolites

1985; Elsevier BV; Linguagem: Inglês

10.1016/s0167-2991(08)65264-7

2542-6613

R. M. Barrer,

Mesoporous Materials and Catalysis

Zeolite synthesis has been considered in terms of factors influencing the species formed and aspects important for systematic study. Zeolites can be divided into categories according to the Si/A1 ratios. Synthesis behaviour varies to some extent between the most aluminous and most siliceous groups. Synthesis of the most siliceous zeolites, which tend to be hydrophobic, is promoted by many organic species, usually basic in nature. Two roles of such compounds have been indicated. Firstly, the host crystal is stabilised by inclusion of guest molecules. This has a thermodynamic basis and is considered specifically in connection with the synthesis of melanophlogite. Secondly, a component of the mixture may act as a template assisting nucleation and crystal growth. Finally, attention has been directed to the method of analysis of curves of yield of crystals against time, developed by Zhdanov and Samulevich. This requires measurements of linear growth rates of the largest crystals and of the final size distribution of crystals.