Sieve materials, history

The history of commercially significant molecular sieve materials from 1954 to 2001 was reviewed in detail by one of us (E.M.F., ref [1]) Highhghts from that review and the subsequent history are presented here. The reader is referred to Chapter 2 for the structures of the materials and to Chapter 3 and ref [25] for a detailed discussion on zeolite synthesis. 

The first part of the book documents the history, structure, chemistry, formulation and characterizations of zeolites in Chapters 1-4. The past 60 years have seen a progression in molecular sieve materials from aluminosilicate zeolites to micro-porous silica polymorphs, microporous aluminophosphate-based polymorphs, metallosihcate and metallophosphate compositions, octahedral-tetrahedral frameworks, mesoporous molecular sieves and, most recently, hybrid metal organic frameworks (MOFs). 

The history of mesoporous material synthesis is unintentionally or intentionally duplicating the development of zeolites and microporous molecular sieve. It starts from silicate and aluminosilicate, through heteroatom substitution, to other oxide compounds and sulfides. It is worth mentioning that many unavailable compositions for zeolite (e.g., certain transition metal oxides, even pure metals and carbon) can be made in mesoporous material form. 

A combination of ion-exchange and molecular sieve properties - as well as their chemical stability has led to their use as heterogeneous catalysts. If the counter ion in a zeolite is a proton this means the materials can essentially behave as solid phase Bronsted adds will promote all the various acid-catalysed reactions in organic chemistry (e.g. cracking, isomerisation, esterifications and aldol reactions) and they have a long history of application as acidic catalysts in the oil refining industries (where the molecular sieving properties are also important) [37],... 

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