Download or read book A Study of Selective Hydrogenation of alpha beta unsaturated Aldehyde in Three Phase Reactors written by Wanida Koo-Amornpattana 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 A Study of Selective Hydrogenation of unsaturated Aldehyde in Three Phase Reactors written by Wanida Koo-Amornpattana 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 Selective Hydrogenation of alpha beta alpha Beta unsaturated Aldehydes Towards Clean Synthesis Over Noble Metal Catalysts in Mass Transfer Efficient Three Phase Reactors written by Laiqi Zhang and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The hydrodynamics and mass transfer characteristics of a concurrent downflow contactor (CDC) are studied in this work in order to investigate the viability of this bubble column as a catalytic reactor for the hydrogenation of?,?-unsaturated aldehydes. Oxygen/water was used as the system throughout. In order to obtain reproducible results, a very effective gas-liquid separation method was conceived and developed after much trial and error work. Shutdown and deadleg gas holdup measuring methods were compared and it was found that the shutdown method is more reliable than the deadleg method. The hydrogenation of cinnamaldehyde using both in-house-prepared and commercial palladium, platinum and ruthenium catalysts was carried out in stirred tank reactors and cocurrent downflow reactors in order to study the kinetics and mass transfer characteristics and the selectivity towards the corresponding desired product, hydrocinnamaldehyde or cinnamyl alcohol. When palladium catalysts were used the desired product was hydrocinnamaldehyde. The effects of homogenous reactions, type of solvent, catalyst loading, temperature, pressure, reactant concentration and the effects of promoter or poison on the selectivity towards hydrocinnamaldehyde were investigated systematically. Aldehyde acetals were produced in polar solvents, but not in non-polar solvents. Two methods can be used to obtain hydrocinnamaldehyde selectivity without reduction of the carbonyl double bond: (1) by using non-polar solvents such as toluene; (2) by incorporating poisons or promoters into the reactant solution or onto the surface of the catalysts. 97% selectivity to hydrocinnamaldehyde was achieved. The effects of the solvent, temperature, pressure, catalyst loading, promoters, and reactants concentration on the kinetics were studied and the following reaction kinetics are proposed for the hydrogenation of cinnamaldehyde over non-modified palladium/charcoal catalysts in propan-2-ol and in toluene: Ra = kC\(_{Cat}\)C\(_{H2}\)C\(0_{CAL}\) The apparent activation energy varies with themperature range in propan-2-ol and is 65\(\pm\)5 kJ.mol\({-1}\) in toluene.
Download or read book Selective Hydrogenation of alpha beta unsaturated Aldehydes Towards Clean Synthesis Over Noble Metal Catalysts in Mass Transfer Efficient Three Phase Reactors written by Laiqi Zhang and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The hydrodynamics and mass transfer characteristics of a concurrent downflow contactor (CDC) are studied in this work in order to investigate the viability of this bubble column as a catalytic reactor for the hydrogenation of ?,?-unsaturated aldehydes. Oxygen/water was used as the system throughout. In order to obtain reproducible results, a very effective gas-liquid separation method was conceived and developed after much trial and error work. Shutdown and deadleg gas holdup measuring methods were compared and it was found that the shutdown method is more reliable than the deadleg method. The hydrogenation of cinnamaldehyde using both in-house-prepared and commercial palladium, platinum and ruthenium catalysts was carried out in stirred tank reactors and cocurrent downflow reactors in order to study the kinetics and mass transfer characteristics and the selectivity towards the corresponding desired product, hydrocinnamaldehyde or cinnamyl alcohol. When palladium catalysts were used the desired product was hydrocinnamaldehyde. The effects of homogenous reactions, type of solvent, catalyst loading, temperature, pressure, reactant concentration and the effects of promoter or poison on the selectivity towards hydrocinnamaldehyde were investigated systematically. Aldehyde acetals were produced in polar solvents, but not in non-polar solvents. Two methods can be used to obtain hydrocinnamaldehyde selectivity without reduction of the carbonyl double bond: (1) by using non-polar solvents such as toluene; (2) by incorporating poisons or promoters into the reactant solution or onto the surface of the catalysts. 97% selectivity to hydrocinnamaldehyde was achieved. The effects of the solvent, temperature, pressure, catalyst loading, promoters, and reactants concentration on the kinetics were studied and the following reaction kinetics are proposed for the hydrogenation of cinnamaldehyde over non-modified palladium/charcoal catalysts in propan-2-ol and in toluene: Ra = kC\(-{Cat}\)C\(-{H2}\)C\( 0-{CAL}\) The apparent activation energy varies with themperature range in propan-2-ol and is 65\(\pm\)5 kJ.mol\( {-1}\) in toluene.
Download or read book Selective Hydrogenation of Alpha Beta unsaturated Aldehydes Towards Clean Synthesis Over Noble Metal Catalysts in Mass Transfer Efficient Three Phase Reactors written by Lai Qi Zhang and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of the Selective Hydrogenation of 2 butyne 1 4 diol in Various Forms of Three phase Reactor written by Marwan and published by . This book was released on 1998 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selective Hydrogenation of Multifunctional Organic Reactants in Three Phase Reactors written by Sanjeev Sharma and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selective Hydrogenation of alpha beta Unsaturated Aldehydes Over Ir Catalysts written by J. Gomez-Lopez and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selective Hydrogenation of alpha beta unsaturated Aldehydes Over Metal Catalysts written by Thomas Balder Ludwig Wolfgang Marinelli and published by . This book was released on 1993 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selective Hydrogenation and Transfer Hydrogenation Reactions written by Ronald Alvaro Farrar Tobar and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation describes the research on catalysts active for the selective transfer hydrogenation (TH) of [alpha],[beta]-unsaturated carbonyl compounds using EtOH as H2 source as alternative to commonly used iPrOH. Furthermore, a base-free iron-based protocol is designed and optimized for the novel TH of ester compounds using EtOH as H2 source. In addition, the chemical activity of new single rhodium atoms on Al2O3 is explored. Using limonene as a model compound, only the terminal olefin was hydrogenated and the potential selective character of the catalyst is highlighted.eng
Download or read book British National Bibliography for Report Literature written by and published by . This book was released on 2002-02 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hydroformylation for Organic Synthesis written by Maurizio Taddei and published by Springer. This book was released on 2014-07-08 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Role of Metals and Ligands in Organic Hydroformylation, by Luca Gonsalvi, Antonella Guerriero, Eric Monflier, Frédéric Hapiot, Maurizio Peruzzini. Hydroformylation in Aqueous Biphasic Media Assisted by Molecular Receptors, by Frédéric Hapiot, Hervé Bricout, Sébastien Tilloy, Eric Monflier. Asymmetric Hydroformylation, by Bernabé F. Perandones, Cyril Godard, Carmen Claver. Domino Reactions Triggered by Hydroformylation, by Elena Petricci, Elena Cini. Rhodium-Catalyzed Hydroformylation in Fused Azapolycycles Synthesis, by Roberta Settambolo. Hydroformylation in Natural Product Synthesis, by Roderick W. Bates, Sivarajan Kasinathan.
Download or read book Glycoscience written by Bertram O. Fraser-Reid and published by Springer Science & Business Media. This book was released on 2008-04-14 with total page 2847 pages. Available in PDF, EPUB and Kindle. Book excerpt: As a reflection of the quantum leap that has been made in the study of glycostructures, the first edition of this book has been completely revised and updated. The editors give up-to-date information on glycostructures, their chemistry and chemical biology in the form of a completely comprehensive survey. Glycostructures play highly diverse and crucial roles in a myriad of organisms and important systems in biology, physiology, medicine, bioengineering and technology. Only in recent years have the tools been developed to partly understand the highly complex functions and the chemistry behind them. While many facts remain undiscovered, this MRW has been contributed to by a large number of the world’s leading researchers in the field.
Download or read book Hydrogen Transfer Reactions written by Gabriela Guillena and published by Springer. This book was released on 2016-09-27 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Topics in Current Chemistry Collections presents critical reviews from the journal Topics in Current Chemistry organized in topical volumes. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience. Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field.
Download or read book New Frontiers in Organoselenium Compounds written by Eder João Lenardão and published by Springer. This book was released on 2018-06-29 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents recent advances in and perspectives on the use of organoselenium compounds, primarily highlighting the new frontiers in the field of Green Chemistry, their therapeutic and biological relevance and new materials. Throughout its 200 pages, readers will find an updated and comprehensive review of new aspects of organoselenium chemistry and biochemistry. Fully referenced and written in an easy to read style, it offers readers a primary resource for including organoselenium derivatives in their projects. This book will be of interest to specialists, students and researchers involved in a broad range of fields, from synthetic green chemistry to medicinal chemistry and the chemistry of natural products. The connection between organoselenium compounds and green chemistry, despite having only recently emerged, is one of the subjects of this book. The first chapter highlights the use of Se-containing molecules as reagents and catalysts in new green protocols to access important organic transformations. The book provides a wealth of examples of bioactive Se-containing molecules, especially focusing on those with potential therapeutic uses. The second chapter focuses on the state of the art concerning the role of organoselenium compounds as antioxidants, GPx mimics, and derivatives endowed with different bioactive properties. “Organoselenium in nature” is the title of the third chapter, which equips readers with essential information on the main natural organoselenium compounds and where they are found. Selected aspects of the metabolism of selenium in plants and microorganisms are also discussed. In closing, the book includes a chapter dedicated to recent advances concerning the nonbonding interactions between organochalcogen compounds. This is currently a hot topic in selenium chemistry and biochemistry, and here readers will find key insights into the chalcogen bond and its role in the biological activity of organoselenium compounds.
Download or read book Recoverable and Recyclable Catalysts written by Maurizio Benaglia and published by John Wiley & Sons. This book was released on 2009-08-31 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recoverable and Recyclable Catalysts There is continued pressure on chemical and pharmaceutical industries to reduce chemical waste and improve the selectivity and efficiency of synthetic processes. The need to implement green chemistry principles is a driving force towards the development of recoverable and recyclable catalysts. The design and synthesis of recoverable catalysts is a highly challenging interdisciplinary field combining chemistry, materials science engineering with economic and environmental objectives. Drawing on international research and highlighting recent developments, this book serves as a practical guide for both experts and newcomers to the field. Topics covered include: An introduction to the principles of catalyst recovery and recycling Catalysts on insoluble and soluble support materials Thermomorphic catalysts, self-supported catalysts and perfluorous catalytic systems The development of reusable organic catalysts Continuous flow and membrane reactors Each chapter combines principles with practical information on the synthesis of catalysts and strategies for catalyst recovery. The book concludes with a comparison of different catalytic systems, using case studies to illustrate the key features of each approach. Recoverable and Recyclable Catalysts is a valuable reference source for academic researchers and professionals from a range of pharmaceutical and chemical industries, particularly those working in catalysis, organic synthesis and sustainable chemistry.
Download or read book Gaseous Carbon Waste Streams Utilization written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2019-02-22 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the quest to mitigate the buildup of greenhouse gases in Earth's atmosphere, researchers and policymakers have increasingly turned their attention to techniques for capturing greenhouse gases such as carbon dioxide and methane, either from the locations where they are emitted or directly from the atmosphere. Once captured, these gases can be stored or put to use. While both carbon storage and carbon utilization have costs, utilization offers the opportunity to recover some of the cost and even generate economic value. While current carbon utilization projects operate at a relatively small scale, some estimates suggest the market for waste carbon-derived products could grow to hundreds of billions of dollars within a few decades, utilizing several thousand teragrams of waste carbon gases per year. Gaseous Carbon Waste Streams Utilization: Status and Research Needs assesses research and development needs relevant to understanding and improving the commercial viability of waste carbon utilization technologies and defines a research agenda to address key challenges. The report is intended to help inform decision making surrounding the development and deployment of waste carbon utilization technologies under a variety of circumstances, whether motivated by a goal to improve processes for making carbon-based products, to generate revenue, or to achieve environmental goals.
