Zeolites: A Refined Tool for Designing Catalytic Sites

Zeolites: A Refined Tool for Designing Catalytic Sites PDF Author: L. Bonneviot
Publisher: Elsevier
ISBN: 008054469X
Category : Technology & Engineering
Languages : en
Pages : 585

Get Book Here

Book Description
Formerly, the catalytic use of zeolites was exclusive to the field of acid catalysis. Nowadays, zeolites also find applications as catalysts in a wide array of chemical reactions such as; base catalyzed reactions, Redox reactions and catalytic reactions on transition metals and their complexes in confined environments. The concepts of Brønsted or Lewis acid-base pairs are adequately illustrated in the literature and well-understood in terms of structural and electronic properties of zeolites. By contrast, properties of chemically modified silicates, aluminosilicates and aluminophosphates have not yet been fully explored. The list of oxydo-reduction reactions performed in the presence of these new materials is growing as demonstrated by the selective catalytic reduction of nitrogen oxides or the numerous oxidations employing hydrogen peroxide. Much effort is currently being made to get a better insight into the nature of the sites involved. The zeolite lattice may also be used as a host for encapsulated complexes or metallic clusters allowing the control of nuclearity of these active species and the steric constraints imposed on the reactants. Molecular sieve and shape selectivity effects have also constituted fascinating aspects of zeolite properties. Recent developments leading to increasingly large pore sizes with VPI-5, cloverite and more recently mesoporous molecular sieves have broadened the spectrum of these applications. Indeed, larger and larger reactant and product molecules can be accommodated in these lattices. These new adsorbant/adsorbate systems create additional needs for experimental data and theoretical descriptions of transport properties, in particular of mono- and multi-components diffusion coefficients in the zeolite pore lattice.All these themes, representing the forefront and current trends in zeolite research, were discussed in the submitted papers to the symposium and are widely represented in the selected papers contained in this volume. A feature common to most of these contributions is the combined use of a variety of analytical techniques. Some of these techniques are at the frontier of the latest analytical developments such as multiple scattering EXAFS and bidimensional MAS-NMR.

Zeolites: A Refined Tool for Designing Catalytic Sites

Zeolites: A Refined Tool for Designing Catalytic Sites PDF Author: L. Bonneviot
Publisher: Elsevier
ISBN: 008054469X
Category : Technology & Engineering
Languages : en
Pages : 585

Get Book Here

Book Description
Formerly, the catalytic use of zeolites was exclusive to the field of acid catalysis. Nowadays, zeolites also find applications as catalysts in a wide array of chemical reactions such as; base catalyzed reactions, Redox reactions and catalytic reactions on transition metals and their complexes in confined environments. The concepts of Brønsted or Lewis acid-base pairs are adequately illustrated in the literature and well-understood in terms of structural and electronic properties of zeolites. By contrast, properties of chemically modified silicates, aluminosilicates and aluminophosphates have not yet been fully explored. The list of oxydo-reduction reactions performed in the presence of these new materials is growing as demonstrated by the selective catalytic reduction of nitrogen oxides or the numerous oxidations employing hydrogen peroxide. Much effort is currently being made to get a better insight into the nature of the sites involved. The zeolite lattice may also be used as a host for encapsulated complexes or metallic clusters allowing the control of nuclearity of these active species and the steric constraints imposed on the reactants. Molecular sieve and shape selectivity effects have also constituted fascinating aspects of zeolite properties. Recent developments leading to increasingly large pore sizes with VPI-5, cloverite and more recently mesoporous molecular sieves have broadened the spectrum of these applications. Indeed, larger and larger reactant and product molecules can be accommodated in these lattices. These new adsorbant/adsorbate systems create additional needs for experimental data and theoretical descriptions of transport properties, in particular of mono- and multi-components diffusion coefficients in the zeolite pore lattice.All these themes, representing the forefront and current trends in zeolite research, were discussed in the submitted papers to the symposium and are widely represented in the selected papers contained in this volume. A feature common to most of these contributions is the combined use of a variety of analytical techniques. Some of these techniques are at the frontier of the latest analytical developments such as multiple scattering EXAFS and bidimensional MAS-NMR.

Molecular Sieves

Molecular Sieves PDF Author: Rosemarie Szostak
Publisher: Springer Science & Business Media
ISBN: 9780751404807
Category : Science
Languages : en
Pages : 380

Get Book Here

Book Description
The porous structure of molecular sieves, combined with their chemical composition, makes them uniquely suitable for use as catalysts or catalytic supports. As such, the materials are used in a wide range of chemical reactions, and as components of formulated products. The shape selectivity of the materials further enhances their chemical usefulness, and exploitation of their unique absorption properties holds the key to improving their catalytic properties. To that end, great efforts are being made to find new of different molecular sieves, with altered or tailored structures or chemical composition. The synthesis and characterisation of molecular sieve materials is a considerable challenge, testing both the chemist's understanding and practical skills. In a thorough overhaul of the very successful first edition of this book, the author guides the reader in the basics of sieve structure, synthesis and characterisation, and points the way to the development of new or improved sieve materials. By covering both the principles and practical aspects of sieve synthesis and characterisation, professional chemists, particularly those involved in industrial research and development, will find this book an essential guide to the current state of the art, and a useful starting point in their own research. Academic chemists, including postgraduate students, will find this book an invaluable guide to this exciting and important area of chemistry.

Design And Applications Of Single-site Heterogeneous Catalysts: Contributions To Green Chemistry, Clean Technology And Sustainability

Design And Applications Of Single-site Heterogeneous Catalysts: Contributions To Green Chemistry, Clean Technology And Sustainability PDF Author: John Meurig Thomas
Publisher: World Scientific Publishing Company
ISBN: 1848169299
Category : Science
Languages : en
Pages : 322

Get Book Here

Book Description
For far too long chemists and industrialists have relied on the use of aggressive reagents such as nitric and sulphuric acids, permanganates and dichromates to prepare the massive quantities of both bulk and fine chemicals that are needed for the maintenance of civilised life — materials such as fuels, fabrics, foodstuffs, fertilisers and pharmaceuticals. Such aggressive reagents generate vast quantities of environmentally harmful and often toxic by-products, including the oxides of nitrogen, of metal oxides and carbon dioxide.Now, owing to recent advances made in the synthesis of nanoporous solids, it is feasible to design new solid catalysts that enable benign, mild oxidants to be used, frequently without utilising solvents, to manufacture the products that the chemical, pharmaceutical, agro- and bio-chemical industries require. These new solid agents are designated single-site heterogeneous catalysts (SSHCs). Their principal characteristics are that all the active sites present in the high-area solids are identical in their atomic environment and hence in their energy of interaction with reactants, just as in enzymes.Single-site heterogeneous catalysts now occupy a position of growing importance both academically and in their potential for commercial exploitation. This text, the only one devoted to such catalysts, dwells both on principles of design and on applications, such as the benign synthesis of nylon 6 and vitamin B3. It equips the reader with unifying insights required for future catalytic adventures in the quest for sustainability in the materials used by humankind.Anyone acquainted with the language of molecules, including undergraduates in the physical and biological sciences, as well as graduates in engineering and materials science, should be able to assimilate the principles and examples presented in this book. Inter alia, it describes how clean technology and ‘green’ processes may be carried out in an environmentally responsible manner.

Zeolites and Related Materials: Trends Targets and Challenges(SET)

Zeolites and Related Materials: Trends Targets and Challenges(SET) PDF Author: Antoine Gedeon
Publisher: Elsevier
ISBN: 0080951619
Category : Science
Languages : en
Pages : 1423

Get Book Here

Book Description
The present book "Zeolites and Related Materials: Trends, Targets and Challenges" reports the communications that have been presented at the 4th International FEZA (Federation of European Zeolite Associations) Conference in Paris, September 3-6, 2008. It gives an excellent overview of the present state of the art of ordered nanoporous solids including zeolites as well as synthetic layered materials (clays), nanosized molecular sieves, ordered mesoporous solids, metal-organic-framework compounds (MOFs), carbons, etc. with emphasis on the synthesis, comprehensive characterization and advanced applications. The significant research activities in this domain are due to the outstanding properties of those nanoporous materials that concentrate the collaborative efforts of researchers from material science, chemistry, physical chemistry and physics.The understanding and development of the unique properties of porous materials relies on a unique blend of multidisciplinary knowledge covering material science, with the implication of organic and colloid chemistry, to prepare micro- and mesoporous materials; surface and adsorption sciences sustained by theory and modelling to understand the peculiar behaviour of molecules in confined systems; special branches of catalysis, physics, chemical engineering and life science to design novel applications. - This book summarizes the developments in the area of nanoporous solids at the dawn of the 21st century, useful for both students/young researchers entering the field of nanoporous materials, as well as for senior scientists - Also summarizes the new family of porous compounds, e.g. MOF's and ordered porous carbon - The present state-of-the-art and prospects of nanoporous solids for advanced applications is discussed

Industrial Applications of X-Ray Diffraction

Industrial Applications of X-Ray Diffraction PDF Author: Frank Smith
Publisher: CRC Press
ISBN: 1482276119
Category : Science
Languages : en
Pages : 1012

Get Book Here

Book Description
By illustrating a wide range of specific applications in all major industries, this work broadens the coverage of X-ray diffraction beyond basic tenets, research and academic principles. The book serves as a guide to solving problems faced everyday in the laboratory, and offers a review of the current theory and practice of X-ray diffraction, major

Post-Synthesis Modification I

Post-Synthesis Modification I PDF Author: Hellmut G. Karge
Publisher: Springer
ISBN: 3540697500
Category : Science
Languages : en
Pages : 452

Get Book Here

Book Description
This comprehensive series covers the science and technology of zeolites and all related microporous and mesoporous materials. Authored by renowned experts, volume 3 deals with the most widely employed techniques for the post-synthesis modification of molecular sieves.

Chemistry of Zeolites and Related Porous Materials

Chemistry of Zeolites and Related Porous Materials PDF Author: Ruren Xu
Publisher: John Wiley & Sons
ISBN: 0470822368
Category : Science
Languages : en
Pages : 695

Get Book Here

Book Description
Widely used in adsorption, catalysis and ion exchange, the family of molecular sieves such as zeolites has been greatly extended and many advances have recently been achieved in the field of molecular sieves synthesis and related porous materials. Chemistry of Zeolites and Related Porous Materials focuses on the synthetic and structural chemistry of the major types of molecular sieves. It offers a systematic introduction to and an in-depth discussion of microporous, mesoporous, and macroporous materials and also includes metal-organic frameworks. Provides focused coverage of the key aspects of molecular sieves Features two frontier subjects: molecular engineering and host-guest advanced materials Comprehensively covers both theory and application with particular emphasis on industrial uses This book is essential reading for researches in the chemical and materials industries and research institutions. The book is also indispensable for researches and engineers in R&D (for catalysis) divisions of companies in petroleum refining and the petrochemical and fine chemical industries.

Supported Catalysts and Their Applications

Supported Catalysts and Their Applications PDF Author: David C Sherrington
Publisher: Royal Society of Chemistry
ISBN: 1847551963
Category : Science
Languages : en
Pages : 282

Get Book Here

Book Description
The need to improve both the efficiency and environmental acceptability of industrial processes is driving the development of heterogeneous catalysts across the chemical industry, including commodity, specialty and fine chemicals and in pharmaceuticals and agrochemicals. Drawing on international research, Supported Catalysts and their Applications discusses aspects of the design, synthesis and application of solid supported reagents and catalysts, including supported reagents for multi-step organic synthesis; selectivity in oxidation catalysis; mesoporous molecular sieve catalysts; and the use of Zeolite Beta in organic reactions. In addition, the two discrete areas of heterogeneous catalysis (inorganic oxide materials and polymer-based catalysts) that were developing in parallel are now shown to be converging, which will be of great benefit to the whole field. Providing a snapshot of the state-of-the-art in this fast-moving field, this book will be welcomed by industrialists and researchers, particularly in the agrochemicals and pharmaceuticals industries.

Recent Advances and New Horizons in Zeolite Science and Technology

Recent Advances and New Horizons in Zeolite Science and Technology PDF Author: H. Chon
Publisher: Elsevier
ISBN: 0080543901
Category : Technology & Engineering
Languages : en
Pages : 485

Get Book Here

Book Description
This volume was conceived as a handbook for the Pre-Conference Summer School on Zeolites, held in Taejon, Korea. The 11th IZC Summer School was organized to acquaint those already actively working in zeolite science and technology with the latest developments and to develop new prospects of zeolite science and technology for the 21st century.The aim of this volume is to give an extensive review and analysis of the important new findings of the last 10 years on the synthesis, characterization and applications of zeolite materials as well as the prediction of new R&D directions for the next decade.

The Reconstruction of Natural Zeolites

The Reconstruction of Natural Zeolites PDF Author: Habbib Ghobarkar
Publisher: Springer Science & Business Media
ISBN: 1441991425
Category : Science
Languages : en
Pages : 168

Get Book Here

Book Description
More than seventeen years have passed now since Glauco Gottardi and Ermano Galli 1 have published their remarkable book on «NATURAL ZEOLITES» where properties and features of naturally occuring phases then available have been compiled. Several new natural zeolites have been found since then, but also natural counterparts ofzeolites which have only been known as synthesis products. The natural formation conditions of zeolites could only be deduced and estimated from their geological environment at the time when NATURAL ZEOLITES has been published, as zeolite synthesis was mainly focused on procedures at low pressures such as those introduced by Barrer and co workers'. Natural zeolites, however, had only been obtained "occasionally" and systematic study to reconstruct these formation conditions has not been performed ever since. This book is focused on the synthesis of natural zeolites by simulating the natural synthesis conditions in the laboratory which are essentially different in means and results from those obtained by conventional synthesis methods. Although the synthesis in the laboratory has undoubtly a great number of advantages over nature such as the employment of proper precursors or the choice of pressure and temperature in a wide range, the synthesis time is very limited in respect to natural conditions: synthesis times ofyears or even tens ofyears which would be necessary to obtain synthesis results for some zeolites- e.g. at 4°C (deep sea conditions) are rather unrealistic.