Download or read book Organically Modified Mesoporous Silica as a Support for Synthesis and Catalysis written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Mesoporous silicates are excellent materials for supported catalysis due to their ease of functionalization, tunable pore size and high surface areas. Mesoporous silicates have been utilized in a variety of applications such as drug delivery scaffolds and catalyst supports. Functionalization of the surface can be achieved by either grafting of alkoxy silanes or co-condensation of the organosilane with the inorganic silica source. My research in this area can be divided into two components. In the first, we address the significant issue of metal contamination after reactions that are catalyzed by transition metals. In the second, we examine the design of new catalysts based on organic/inorganic composites. Ruthenium catalyzed processes such as olefin metathesis or asymmetric hydrogenation, are often underutilized due to the difficulty of removing the ruthenium by-products. Attempts to remove ruthenium involve treating the solution with a scavenging reagent followed by silica chromatography. Often these scavenging agents are expensive phosphines or toxic agents like lead tetra-acetate. SBA-15 functionalized with aminopropyl triethoxysilane displays a high affinity for ruthenium. Furthermore, it can be utilized to remove ruthenium by-products from olefin metathesis or hydrogenation reactions without the need for silica chromatography. We have also prepared sulfur-functionalized mesoporous silicates that have a high affinity for palladium. The materials after loading prove to be active catalysts for a variety of palladium catalyzed processes such as Suzuki-Miyaura and Sonogashira couplings. The catalysts are recyclable with moderate loss of activity and structure, depending on the method of incorporation of the thiol. We have characterized the as-synthesized and used catalysts by nitrogen sorption, TEM, X-ray photoelectron spectroscopy (XPS) and a variety of homogeneity tests were performed on the catalysts. Periodic mesoporous organosilicates (PMOs) are a well known cl.

Download or read book Micro Mesoporous Metallosilicates written by Peng Wu and published by John Wiley & Sons. This book was released on 2024-05-28 with total page 501 pages. Available in PDF, EPUB and Kindle. Book excerpt: Micro-Mesoporous Metallosilicates Up-to-date and in-depth text bridging the technology gap between fundamental research and industry-scale applications of porous materials for catalysis Micro-Mesoporous Metallosilicates: Synthesis, Characterization, and Catalytic Applications comprehensively introduces the chemistry and catalytic technologies of metallosilicates, an important family of microporous crystalline zeolite and heteroatom-containing mesoporous materials, with a primary focus on design synthesis, characterization, theoretical studies, and catalytic applications of titanosilicates, tin-silicates, germanosilicates and Ti-mesosilica, and more. The text covers recent advances in the synthesis of titanosilicates, including hydrothermal synthesis, dry-gel conversion, fluoride-assisted synthesis, and post-synthesis methods, along with the synthesis of metallosilicates with two-dimensional lamellar structures and their structural modifications as well as applications in selective oxidation reactions. The text also discusses synthesis of germanosilicates with specially designed organic structure-directing agents, synthesis and catalytic applications of heteroatom-containing mesoporous silica, and dendritic mesoporous silica nanoparticles with unique wrinkled center-radial structures. Overall, every important porous metallosilicate and its synthesis, characterization, pore engineering, catalytic application, and industrial technique and process are covered. Specific sample topics discussed in Micro-Mesoporous Metallosilicates include: Chemical post-modifications of titanosilicates, in terms of the effects on transfer, adsorption/desorption, and surface reactions X-Ray based techniques, ultraviolet-visible-near infrared spectroscopy, Raman spectroscopy, and solid-state NMR spectroscopy Theoretical calculation as an effective tool and supplement to understand the catalytic active center, structural character, and Brønsted/Lewis acidity Titanosilicates in the liquid-phase epoxidation reaction of propylene and propylene chloride to corresponding epoxides Effects of particle sizes, oxidation state, and location sites of Au nanoparticles, and epoxidation performance of Ti-containing materials Delivering cutting-edge research and bridging the technology gap between fundamental research and industrial applications, Micro-Mesoporous Metallosilicates is a valuable resource for chemists, materials scientists, chemical engineers, and experienced researchers in related fields.

Download or read book Organically Modified Mesoporous Silicas as Base Catalysts for Green Chemistry written by James Epiphan Gabriel Mdoe and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nanoporous Materials III written by M. Jaroniec and published by Elsevier. This book was released on 2002-05-15 with total page 711 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoporous Materials III contains the invited lectures and peer-reviewed oral and poster contributions to be presented at the 3rd Conference on Nanoporous Materials, which will be hosted in Ottawa, Canada, June 2002. The work covers complementary approaches to and recent advances in the field of nanostructured materials with pore sizes larger than 1nm, such as periodic mesoporous molecular sieves M41S and FSM16 and related materials including clays, carbon molecular sieves, colloidal crystal templated organic and inorganic materials, porous polymers and sol gels. The broad range of topics covered in relation to the synthesis and characterization of ordered mesoporous materials are of great importance for advanced adsorption, catalytic and separation processes as well as the development of nanotechnology. The contents of this title are based on topics to be discussed by invited lecturers, which deal with periodic mesoporous organosilicas, stability and catalytic activity of aluminosilicate mesostructures, electron microscopy studies of ordered materials, imprinted polymers and highly porous metal-organic frameworks. The other contributions deal with tailoring the surface and structural properties of nanoporous materials, giving a detailed characterization as well as demonstrating their usefulness for advanced adsorption and catalytic applications.

Download or read book Hydrogels and Biodegradable Polymers for Bioapplications written by Raphael M. Ottenbrite and published by . This book was released on 1996 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: The theme of the August 1994 symposium was hydrogel biodegradation and bioapplications. Hydrogels are formed by adding a small amount of cross-linked macromolecular material to a large amount of water, which produces an apparent solid. This volume addresses reversible hydrogels, stimuli-sensitive hydrogels. and some in vivo applications of hydrogels. The volume contains 20 chapters and is directed to organic, physical, polymer, and biochemists as well as biologists, materials scientists, and bioengineers. Annotation copyright by Book News, Inc., Portland, OR

Download or read book Clean Synthesis Using Porous Inorganic Solid Catalysts and Supported Reagents written by James H Clark and published by Royal Society of Chemistry. This book was released on 2007-10-31 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt: Waste minimisation has a number of aims which include enhancing the intrinsic selectivity of any given process, providing a means of recovering reagents in a form which allows easy regeneration and the replacement of stoichiometric processes with catalytic ones. Solids, as catalysts or as supports for other reagents, offer potential for benefit in all these areas. This monograph provides an overview of the properties of the more useful solid catalysts and supported reagents, and highlights their most valuable applications in the preparation of organic chemicals in liquid phase reactions. Clean Synthesis Using Porous Inorganic Solid Catalysts and Supported Reagents is concerned with the use of solid catalysts in the clean synthesis of organic chemicals. The emphasis is on chemical processes of importance to the manufacture/preparation of fine and speciality chemicals, chemical intermediates and pharmaceutical intermediates, especially where catalysis is not currently used or where current catalysts are homogeneous, leading to difficult separation procedures and unacceptable levels of waste. This book focuses on solid catalysts based on inorganic supports and covers the emerging area of chemically modified mesoporous solid catalysts.

Download or read book Periodic Mesoporous Organosilicas written by Chang-Sik Ha and published by Springer. This book was released on 2018-11-07 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive overview of the fundamental properties, preparation routes and applications of a novel class of organic–inorganic nanocomposites known as periodic mesoporous organosilicas (PMOs). Mesoporous silicas are amorphous inorganic materials which have silicon and oxygen atoms in their framework with pore size ranging from 2 to 50 nm. They can be synthesized from surfactants as templates for the polycondensation of various silicon sources such as tetraalkoxysilane. In general, mesoporous silica materials possess high surface areas, tunable pore diameters, high pore volumes and well uniformly organized porosity. The stable chemical property and the variable ability for chemical modification makes them ideal for many applications such as drug carrier, sensor, separation, catalyst, and adsorbent. Among such mesoporous silicas, in 1999, three groups in Canada, Germany, and Japan independently developed a novel class of organic–inorganic nanocomposites known as periodic mesoporous organosilicas (PMOs). The organic functional groups in the frameworks of these solids allow tuning of their surface properties and modification of the bulk properties of the material. The book discusses the properties of PMOs, their preparation, different functionalities and morphology, before going on to applications in fields such as catalysis, drug delivery, sensing, optics, electronic devices, environmental applications (gas sensing and gas adsorption), biomolecule adsorption and chromatography. The book provides fundamental understanding of PMOs and their advanced applications for general materials chemists and is an excellent guide to these promising novel materials for graduate students majoring in chemical engineering, chemistry, polymer science and materials science and engineering.

Download or read book Silica Based Materials for Advanced Chemical Applications written by Mario Pagliaro and published by Royal Society of Chemistry. This book was released on 2009-03-16 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first book to address the hot topic of functional silica gels and their applications. Originally used mainly in chromatography, specialized silica gels have evolved into crucially important functional nanomaterials suitable for use in, amongst other things, chemical synthesis, analysis, purification, surface protection and drug release. It is estimated that the world's current 1 billion dollar market for sol-gels (mostly silica-based) will grow by more than 5% per year from 2006 to 2011. Actually, as many revolutionary products are now reaching the market, it will increase much faster. Commercial applications include glasses, paints, catalysts and fragrances. Medical uses include the delivery of vitamins, hormones and acne treatments and the synthesis of the powerful anticancer drug, taxol. Sol-gel technology also forms the basis of the MetaChip, thanks to which potential new drugs can be identified rapidly and simultaneously. With content relevant to both scientific and commercial viewpoints, the book will interest researchers and undergraduates as well as managers and consultants in the chemical industry. Those from an industrial background will gain a clear picture of what this technology is all about and how it can be used to solve their specific problems. All readers will benefit from the clear, concise style and consistent treatment of topics. The book demonstrates how chemists synthesize, from the bottom-up, tailor-made (nano)materials of immense practical importance spanning the fields of chemistry, physics, materials science, engineering, biology and medicine. It also shows how the versatility of silica gels results from their physical and chemical properties. An updated outlook on new commercial products, and the companies which make them, greatly adds relevance and practical value to the text.

Download or read book Ordered mesoporous silica COK 12 mesoscale tailoring upscaling continuous synthesis and application in the oxidative coupling of methane written by Colmenares, Maria and published by Universitätsverlag der TU Berlin. This book was released on 2018-07-19 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ordered mesoporous silica (OMS) materials are a family of silica nanomaterials with pores ranging in size from 2 to 50 nm which are arranged periodically within the silica matrix. They have expanding applications in various fields of research, such as drug delivery, adsorption, separation and catalysis. COK-12 is an OMS produced by the soft-templating method, using the block copolymer P123 as a structure-directing agent. The synthesis takes place at room temperature under mild reaction conditions. In comparison with the most widely known OMS, the synthesis of COK-12 is more time efficient, inexpensive and environmentally friendly, yielding a material analogous to the well-known SBA-15. This thesis encompasses investigations regarding the production of the ordered mesoporous silica material (OMS) known as COK-12, in terms of upscaling of the synthesis and tailoring of the size and shape of its characteristic hexagonal pore structure. Batch upscaling of the synthesis yielded a material with nearly identical properties to that of the original COK-12. Upscaling of the COK-12 synthesis was also studied in continuous mode. The installation and operation of a continuous COK-12 production unit was carried out with the aim to determine the possibility of large-scale production of COK-12 with consistent material properties. COK-12 was produced in continuous mode by varying the time of aging of the COK-12 slurry and the flow rate of the feed streams, yielding materials with properties nearly identical to those of the original COK-12. COK-12 was used as a support for the Na2WO4-Mn/SiO2 catalyst for the oxidative coupling of methane reaction in various forms (powder, granular produced by pressing and monolithic), showing promising results comparable to the enhanced activity of the catalyst supported on the SBA-15. The advantage of using COK-12 over other OMS materials is that the facile nature of COK-12 synthesis makes it a viable candidate for industrial production of the Na2WO4-Mn/SiO2 catalyst, if paired with appropriate pelletizing and preparation method. The introduction of hexane and polypropylene glycol (PPG) as micellar swelling agents into the original COK-12 synthesis was studied in order to tailor the mesoporous structure of the system. Hexane was used as a micelle expander and as an agent to produce silica mesocellular foams, with “ink-bottle” shaped pores with a larger diameter than that of the original COK-12. By adding PPG into the synthesis, the shift of the mesostructure of COK-12 from 2D hexagonal to a multilamellar vesicular configuration was studied, resulting in the progressive formation of this type of material with increasing concentration of PPG. The flexibility of the COK-12 synthesis in terms of upscaling and tailoring of the mesostructure was examined throughout this work, with an aim to contribute to the existing and expanding knowledge regarding more versatile, sustainable and possibly industrial OMS production. Ordered Mesoporous Silica (OMS) gehört zu der Familie der Silica-Nanomaterialien mit periodisch angeordneten Mesoporen im Größenbereich zwischen 2 und 50 nm. Diese werden zunehmend in unterschiedlichen Forschungsfeldern wie Medikamentenfreisetzung, Adsorption, Separation und Katalyse eingesetzt. COK-12 ist ein OMS, das über eine Soft-Templating-Methode unter Nutzung des Blockcopolymers P123 als strukturbestimmenden Zusatz erzeugt wird. Die Synthese erfolgt bei Raumtemperatur unter milden Reaktionsbedingungen. Im Vergleich zu den am weitesten bekannten OMS-Materialien ist die Synthese von COK-12 zeiteffizient, günstig und umweltfreundlich. Dabei wird ein OMS-Material analog zu dem bereits etablierten SBA-15 erzeugt. Die vorliegende Dissertation umfasst die Synthese eines als COK-12 bekannten OMS-Materials, dem Scale-Up der Synthese sowie die Anpassung und Modifizierung der ursprünglich hexagonal-angeordneten Mesoporen bezüglich Porengrößen und Porenform. Das diskontinuierliche Scale-Up im Batchprozess führt zu nahezu identischen Materialeigenschaften im Vergleich zu dem ursprünglichen COK-12. Ein Scale-Up der COK-12-Synthese wurde zusätzlich im kontinuierlichen Prozess erprobt. Dessen Installation und Operation wurde mit dem Ziel durchgeführt, um die Möglichkeit einer Produktion von großen Mengen an COK-12 mit einheitlichen Materialeigenschaften zu validieren. Durch eine Variation der Alterungszeit als auch der Fließrate der Lösungen konnte COK-12 im kontinuierlichen Prozess mit nahezu identischen Eigenschaften wie das ursprüngliche COK-12 erzeugt werden. COK-12 wurde erfolgreich in verschiedenen Formen (Pulver, Pressgranulate und Monolithe) als Trägermaterial für Na2WO4-Mn/SiO2-Katalysatoren für die Oxidative Kopplung von Methan eingesetzt. Die resultierenden Aktivitäten ist sind vergleichbar mit denen des auf SBA-15-geträgerten Katalysators Der Vorteil der Nutzung von COK-12 im Vergleich zu anderen OMS-Materialien liegt in der vergleichsweise simplen COK-12-Synthese, weshalb es ein interessanter Kandidat für eine mögliche industrielle Produktion des Na2WO4-Mn/SiO2-Katalysators ist, wenn wenn geeignete Pelletierungs- und Herstellungsmethoden angewendet werden. Die Zugabe von Hexan und Polypropylenglykol (PPG) zur Aufweitung der Mizellen in der ursprünglichen COK-12-Synthese wurde untersucht, um die mesoporöse Struktur des Systems zu variieren. Hexan wurde eingesetzt zur Aufweitung der Mizellen und als Hilfsmittel zur Produktion mesozellulärer Silica-Schäume mit „ink-bottle“-förmigen Poren sowie vergrößertem Porendurchmesser im Vergleich zu denen des ursprünglichen COK-12. Durch die Zugabe von PPG in die Synthese verändert sich die Mesoporenstruktur der ursprünglichen hexagonalen 2D-Struktur zu einer multilamellaren vesikulären Anordnung, die mit zunehmender PPG-Konzentration verstärkt wird. Die Flexibilität der COK-12-Synthese wurde in dieser Arbeit in Bezug auf ein Scale-Up und eine Porenmodifikation weitreichend untersucht, mit dem Ziel das existierende Wissen in Bezug auf eine vielseitige, nachhaltige sowie eine potentielle Industrieproduktion der COK-12-Synthese zu entwickeln.

Download or read book Mesoporous Molecular Sieves 1998 written by L. Bonneviot and published by Elsevier. This book was released on 1998-07-08 with total page 633 pages. Available in PDF, EPUB and Kindle. Book excerpt: The original properties of mesoporous molecular sieves are so unique that the design of most existing catalysts could be reconsidered. It might indeed be of interest to introduce MMS either as a support or as the active phase, merely on the basis of their high surface areas, narrow pore size distribution and flexibility in composition. The recent literature provides examples of MMS based catalysts of many types such as acid-base solids, supported metals and supported oxides, mixed oxides, anchored complexes and clusters, grafted organic functional groups and others. Examples of all these developments are documented in the present proceedings including some spectacular new proposals. The new metallic (Pt) mesophases are specially worth mentioning because they represent a new approach to producing non-supported highly dispersed metals.In these proceedings the reader will find feature articles and regular papers from many worldwide groups, covering all aspects of synthesis, physical characterization and catalytic reactivity of MMS and their chemically modified forms. It is actually remarkable that this recent development brought together an even broader spectrum of scientists from traditionally unrelated fields such as those of liquid crystals, surfactants, sol-gels, amorphous oxides and mixed oxides, solid state, adsorbents and heterogeneous catalysts. Obviously, this is a fast-growing research area which triggers the imagination and creativity at the cross-road between material design, molecular surface tailoring and catalytic applications.

Download or read book Advances in Organic Synthesis written by Atta-ur-Rahman and published by Bentham Science Publishers. This book was released on 2013-01-10 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Organic Synthesis is a book series devoted to the latest advances in synthetic approaches towards challenging structures. It presents comprehensive articles written by eminent authorities on different synthetic approaches to selected target molecules and new methods developed to achieve specific synthetic transformations. Contributions are written by eminent scientists and each volume is edited by an authority in the field. Advances in Organic Synthesis is essential for all organic chemists in the academia and industry who wish to keep abreast of rapid and important developments in the field.

Download or read book Update on Silica based Mesoporous Materials for Biomedical Applications written by Luigi Pasqua and published by Smithers Rapra. This book was released on 2011-11-22 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an insightful understanding of the mesoporous silica structure and its special properties. The details of synthesis and modification strategies are discussed by reviewing the open literature. The discussion concerning the potential of mesoporous silica in modern biomedical applications will be related to a critical analysis in the field of material science. This book will help the reader rapidly develop the necessary tools to follow the design of the different mesoporous silica-based devices presented in the various studies. The structure of the different devices is examined in detail and the relationship between the structure and the expected activity are discussed. It will also assist in the ability to design new therapeutic devices in a field where the applications seem to be without limits.

Download or read book Chemistry of Silica and Zeolite Based Materials written by Abderrazzak Douhal and published by Elsevier. This book was released on 2019-07-04 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemistry of Silica and Zeolite-Based Materials covers a wide range of topics related to silica-based materials from design and synthesis to applications in different fields of science and technology. Since silica is transparent and inert to the light, it is a very attractive host material for constructing artificial photosynthesis systems. As an earth-abundant oxide, silica is an ideal and basic material for application of various oxides, and the science and technology of silica-based materials are fundamentally important for understanding other oxide-based materials. The book examines nanosolvation and confined molecules in silica hosts, catalysis and photocatalysis, photonics, photosensors, photovoltaics, energy, environmental sciences, drug delivery, and health. Written by a highly experienced and internationally renowned team from around the world, Chemistry of Silica and Zeolite-Based Materials is ideal for chemists, materials scientists, chemical engineers, physicists, biologists, biomedical sciences, environmental scientists, toxicologists, and pharma scientists. --- "The enormous versatility of silica for building a large variety of materials with unique properties has been very well illustrated in this book.... The reader will be exposed to numerous potential applications of these materials – from photocatalytic, optical and electronic applications, to chemical reactivity in confined spaces and biological applications. This book is of clear interest not only to PhD students and postdocs, but also to researchers in this field seeking an understanding of the possible applications of meso and microporous silica-derived materials." - Professor Avelino Corma, Institute of Chemical Technology (ITQ-CSIC) and Polytechnical University of Valencia, Spain Discusses the most important advances in various fields using silica materials, including nanosolvation and confined molecules in silica hosts, catalysis and photocatalysis, and other topics Written by a global team of experts from a variety of science and technology disciplines Ideal resource for chemists, materials scientists, and chemical engineers working with oxide-based materials

Download or read book Synthesis and Characterization of Mesoporous Organically Modified Silicate Films written by Norma Edith Sosa Cortes and published by . This book was released on 2004 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mesoporous Materials A New Generation In Material Science written by Pallavi Bhange and published by LAP Lambert Academic Publishing. This book was released on 2012 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: The attempts have been made to substitute Si4+ isomorphously with other cations (Sn4+ and Al3+) in the mesoporous materials under certain controlled conditions of pH and pre-hydrolysis, have ended up with the incorporating metal ions in different locations and environments. The work includes new investigations on different aspects such as synthesis procedures, synthesis mechanisms, heteroatom insertion, catalytic applications, thermal stability, physico-chemical characterization and enzyme immobilization.

Download or read book Heterogeneous Catalysis in Sustainable Synthesis written by Bela Torok and published by Elsevier. This book was released on 2021-09-17 with total page 678 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heterogeneous Catalysis in Sustainable Synthesis is a practical guide to the use of solid catalysts in synthetic chemistry that focuses on environmentally benign applications. Collating essential information on solid catalysts into a single volume, it reveals how the efficient use of heterogeneous catalysts in synthetic chemistry can support sustainable applications. Beginning with a review of the fundamentals of heterogeneous catalytic synthesis, the book then explores the basic concepts of heterogeneous catalytic reactions from adsorption to catalyst poisons, the use of non-traditional activation methods, recommended solvents, the major types of both metal and non-metal solid catalysts, and applications of these catalysts in sustainable synthesis. Based on the extensive experience of its expert author, this book aims to encourage and support synthetic chemists in using solid catalysts in their own work, while also highlighting the important link between heterogeneous catalysis and sustainability to all those interested. - Combines foundational knowledge with a focus on practical applications - Organizes information by reaction type, allowing readers to easily find examples of how to carry out specific reaction types with solid catalysts - Highlights emerging areas such as nanoparticle catalysis and metal-organic framework (MOF) based catalysts

Download or read book Synthesis and Postmodification of Functionally Relevant Organically Modified Silica Particles written by Eric Brozek and published by . This book was released on 2013 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: