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Pore size engineering in zeolites
BOOKREVIEWS Introduction to Zeolite Science and Practice H. van Bekkum, E.M. Flanigen and J.C. Jansen, Editors Studies in Surface Science and Catalysis, Vol. 58, Elsevier, Amsterdam, 1991, ISBN 0-444-88969-8, 769 pp., US $225.50/Dfl 395.00
T h e organizing committee of the 8th International Conference on Zeolites that was held in Amsterdam from July 10--14, 1989 decided that there was a need for a pre-conference school on zeolite science aimed mainly at introducing the subject to comparatively young scientists who had recently become involved in zeolite research. T h e school was a great success and was attended by approximately ninety persons. T h e success of the school was due, undoubtedly, to the quality and experience o f the teachers invited by the editors o f this book to participate in the school. T h e present book, which was conceived during the school, was considered perfectly suitable as a basis for an introductory book on zeolites and related materials, covering both theory and practice. T h e International Zeolite Association (IZA) Council has recommended that all the future IZA conferences have a pre-conference school. This recommendation has been accepted by the organizing committee of the 9th IZA Conference to be held in Montreal, Canada from July 5-10, 1992 and the committee has organized a zeolite school in Montreal from July 2-4, 1992. T h e recommendation has also been accepted by the organizing committee of the 10th IZA Conference to be held in Garmisch-Partenkirchen, Germany from July 17-22, 1994. Both of these schools will use this book as the basic text with lecturers updating their respective topics. T h e book contains 16 chapters and two useful appendices on zeolite structures and pore sizes, respectively. T h e chapters, in order, are: T h e Zeolite Scene (L. Moscou); Zeolites and Molecular Sieves (E. Flanigen); Structural Subunits in Silicate and Phosphate Structures (H. van Koningsveld); Synthesis of Zeolites (J.C. Jansen) and A1PO4-based Molecular Sieves (S.T. Wilson); Modified Zeolites (R. Szostak); Clays (R.A. Schoonheydt); Techniques for Zeolite Characterization (J.H.C. van H o o f f and J.W. Roelofsen); Solidstate NMR Spectroscopy (G. Engelhardt); Zeolite T h e o r y and Modelling
(R.A. van Santen, D.P. de Bruyn, C J J . den Ouden and B. Smit); Ion Exchange (R.P. Townsend); Diffusion (M.F.M. Post); Acid Catalysis in Hydrocarbon Reactions (P.A. Jacobs and J.A. Martens); Preparation of Zeolite Catalysts (H.W. Kouwenhoven and B. de Kroes); Coke Formation (H.G. Karge); Hydrocarbon Processing (I.E. Maxwell and W.H.J. Stork); Zeolites in Organic Synthesis (W.F. Holderich and H. van Bekkum). T h e above chapters cover most o f the areas of research in zeolites and microporous solids and give an excellent introduction of the subject to persons new to the field. However, the coverage in many of the chapters is also of sufficient depth to be useful to more experienced readers. T h e one glaring omission is the lack of a chapter on adsorption. Considering the immense use of zeolites in separation processes, this area will need to be added when the book is updated. As the book is dedicated to Richard M. Barrer and the late Donald W. Breck, it seems strange that the large number o f presentations on adsorption and molecular sieving by R.M. Barrer over the past fifty years is not the subject of a chapter. T h e book is in hardcover but there is a limited edition in paperback for the exclusive use by the International Zeolite Association. Lovat V.C. Rees
Pore Size Engineering in Zeolites by Etienne F. Vansant Wiley and Sons, Chichester, New York, 1990, ISBN 0-471-92779-1, 156 pp., £24.95
T h e aim of this book is succinctly stated in the title and is well-addressed in the text. It is a very recommendable review of the different techniques that can be applied to modify the porosity of zeolites in a controlled way. It provides a very useful source for those engaged in separation, encapsulation and catalyst technology. T h e book is written with the intent that it should also be used by research scientists, and as such it is also recommendable for MSc and PhD students. On the whole, the author adopts a clear and logical style and, furthermore, shows his fascination with his subject. Another mark of the book is the manner in
which observations are often described to provide a stimulus for future research work. After a general introduction the author discusses the different methods of pore size engineering: (i) cation exchange or decationization, (ii) the preadsorption of polar molecules, and (iii) the chemical modification of the zeolite structure using reactants such as silane or diborane. Having briefly reviewed the first two methods, the author describes the chemical modification of the zeolite framework in a comprehensive manner. Over the last years his research team has modified zeolites by silanation, boranation, emplantation of boron-nitrogen compounds and treatment with inorganic acids and their salts. T h e emphasis here is on the chemical principles that are frequently discussed in an original and convincing manner. The next section deals with applications of the pore size engineering in zeolites with an emphasis on the encapsulation and separation of gases. T h e author discusses a method for the immobilization of radioactive Kr-85 based on an adsorption process in an aluminosilicate followed by a structural modification procedure. The advantage is that this method can be carried out at 300 K and 1 bar. The gas-substrate system is thermally stable and possesses a high stability towards change of pH and z-irradiation. As pointed out, this method is cheaper and more flexible compared to more classical methods (e.g., storage of Kr85 in pressurized cylinders). A brief chapter follows that deals with the separation of gas-mixtures on a modified H-mordenite and reveals that zeolites can be tailored by pore-size engineering to achieve efficient separation of gases. The appendix considers principally the design of laboratory scale and pre-pilot scale equipment in a satisfactory manner. T h e book is well-presented and contains few errors. It will be of considerable use to practicing chemists and chemical engineers. I have no hesitation in recommending this text. In summary, it gives an up-to-date review of current research activities in the field of zeolitic pore size engineering. Furthermore, I can recommend the booklet to scientists as an introduction to an interesting new field. P. Brftckner
ZEOLITES, 1992, Vol 12, July/August 767
T h e organizing committee of the 8th International Conference on Zeolites that was held in Amsterdam from July 10--14, 1989 decided that there was a need for a pre-conference school on zeolite science aimed mainly at introducing the subject to comparatively young scientists who had recently become involved in zeolite research. T h e school was a great success and was attended by approximately ninety persons. T h e success of the school was due, undoubtedly, to the quality and experience o f the teachers invited by the editors o f this book to participate in the school. T h e present book, which was conceived during the school, was considered perfectly suitable as a basis for an introductory book on zeolites and related materials, covering both theory and practice. T h e International Zeolite Association (IZA) Council has recommended that all the future IZA conferences have a pre-conference school. This recommendation has been accepted by the organizing committee of the 9th IZA Conference to be held in Montreal, Canada from July 5-10, 1992 and the committee has organized a zeolite school in Montreal from July 2-4, 1992. T h e recommendation has also been accepted by the organizing committee of the 10th IZA Conference to be held in Garmisch-Partenkirchen, Germany from July 17-22, 1994. Both of these schools will use this book as the basic text with lecturers updating their respective topics. T h e book contains 16 chapters and two useful appendices on zeolite structures and pore sizes, respectively. T h e chapters, in order, are: T h e Zeolite Scene (L. Moscou); Zeolites and Molecular Sieves (E. Flanigen); Structural Subunits in Silicate and Phosphate Structures (H. van Koningsveld); Synthesis of Zeolites (J.C. Jansen) and A1PO4-based Molecular Sieves (S.T. Wilson); Modified Zeolites (R. Szostak); Clays (R.A. Schoonheydt); Techniques for Zeolite Characterization (J.H.C. van H o o f f and J.W. Roelofsen); Solidstate NMR Spectroscopy (G. Engelhardt); Zeolite T h e o r y and Modelling
(R.A. van Santen, D.P. de Bruyn, C J J . den Ouden and B. Smit); Ion Exchange (R.P. Townsend); Diffusion (M.F.M. Post); Acid Catalysis in Hydrocarbon Reactions (P.A. Jacobs and J.A. Martens); Preparation of Zeolite Catalysts (H.W. Kouwenhoven and B. de Kroes); Coke Formation (H.G. Karge); Hydrocarbon Processing (I.E. Maxwell and W.H.J. Stork); Zeolites in Organic Synthesis (W.F. Holderich and H. van Bekkum). T h e above chapters cover most o f the areas of research in zeolites and microporous solids and give an excellent introduction of the subject to persons new to the field. However, the coverage in many of the chapters is also of sufficient depth to be useful to more experienced readers. T h e one glaring omission is the lack of a chapter on adsorption. Considering the immense use of zeolites in separation processes, this area will need to be added when the book is updated. As the book is dedicated to Richard M. Barrer and the late Donald W. Breck, it seems strange that the large number o f presentations on adsorption and molecular sieving by R.M. Barrer over the past fifty years is not the subject of a chapter. T h e book is in hardcover but there is a limited edition in paperback for the exclusive use by the International Zeolite Association. Lovat V.C. Rees
Pore Size Engineering in Zeolites by Etienne F. Vansant Wiley and Sons, Chichester, New York, 1990, ISBN 0-471-92779-1, 156 pp., £24.95
T h e aim of this book is succinctly stated in the title and is well-addressed in the text. It is a very recommendable review of the different techniques that can be applied to modify the porosity of zeolites in a controlled way. It provides a very useful source for those engaged in separation, encapsulation and catalyst technology. T h e book is written with the intent that it should also be used by research scientists, and as such it is also recommendable for MSc and PhD students. On the whole, the author adopts a clear and logical style and, furthermore, shows his fascination with his subject. Another mark of the book is the manner in
which observations are often described to provide a stimulus for future research work. After a general introduction the author discusses the different methods of pore size engineering: (i) cation exchange or decationization, (ii) the preadsorption of polar molecules, and (iii) the chemical modification of the zeolite structure using reactants such as silane or diborane. Having briefly reviewed the first two methods, the author describes the chemical modification of the zeolite framework in a comprehensive manner. Over the last years his research team has modified zeolites by silanation, boranation, emplantation of boron-nitrogen compounds and treatment with inorganic acids and their salts. T h e emphasis here is on the chemical principles that are frequently discussed in an original and convincing manner. The next section deals with applications of the pore size engineering in zeolites with an emphasis on the encapsulation and separation of gases. T h e author discusses a method for the immobilization of radioactive Kr-85 based on an adsorption process in an aluminosilicate followed by a structural modification procedure. The advantage is that this method can be carried out at 300 K and 1 bar. The gas-substrate system is thermally stable and possesses a high stability towards change of pH and z-irradiation. As pointed out, this method is cheaper and more flexible compared to more classical methods (e.g., storage of Kr85 in pressurized cylinders). A brief chapter follows that deals with the separation of gas-mixtures on a modified H-mordenite and reveals that zeolites can be tailored by pore-size engineering to achieve efficient separation of gases. The appendix considers principally the design of laboratory scale and pre-pilot scale equipment in a satisfactory manner. T h e book is well-presented and contains few errors. It will be of considerable use to practicing chemists and chemical engineers. I have no hesitation in recommending this text. In summary, it gives an up-to-date review of current research activities in the field of zeolitic pore size engineering. Furthermore, I can recommend the booklet to scientists as an introduction to an interesting new field. P. Brftckner
ZEOLITES, 1992, Vol 12, July/August 767