Gamma Brass Structures as Catalyst for Selective Hydrogenation of Crotonaldehyde
Title | Gamma Brass Structures as Catalyst for Selective Hydrogenation of Crotonaldehyde PDF eBook |
Author | Chandler Thomas |
Publisher | |
Pages | |
Release | 2019 |
Genre | |
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The selective hydrogenation of crotonaldehyde to form either crotyl alcohol or n-butyraldehyde was studied using Density Function Theory (DFT). Previous work had demonstrated the promise of a palladium-zinc bimetallic catalyst, in both a monomer and trimer form, in favorably hydrogenating the carbon-oxygen double bond. The study was completed through analyzing the calculated energies of the molecular systems and using their relative values to determine favorable arrangements. The results indicate a strong preference for the adsorption of the carbon-carbon double bond over the carbon-oxygen double bond on both the palladium-zinc monomer and trimer surfaces. Further analysis demonstrated that neither surface catalyst would promote the complete reaction of crotonaldehyde to n-butyraldehyde. Both systems resulted in unsurpassable activation barriers leading the catalyst to be inactive for the hydrogenation of crotonaldehyde.
Selective Hydrogenation of Crotonaldehyde by Pt-containing Bimetallic Catalysts Supported on Metal Oxides
Title | Selective Hydrogenation of Crotonaldehyde by Pt-containing Bimetallic Catalysts Supported on Metal Oxides PDF eBook |
Author | Agustin Tomas Colussi |
Publisher | |
Pages | 142 |
Release | 1997 |
Genre | |
ISBN |
The Selective Hydrogenation of Crotonaldehyde Over Bimetallic Catalysts
Title | The Selective Hydrogenation of Crotonaldehyde Over Bimetallic Catalysts PDF eBook |
Author | Ann Marie Schoeb |
Publisher | |
Pages | 286 |
Release | 1996 |
Genre | |
ISBN |
Mechanistic Study for Selective Hydrogenation of Crotonaldehyde Using Platinum/metal-oxide Catalysts -- a Gas-phased Kinetics Study
Title | Mechanistic Study for Selective Hydrogenation of Crotonaldehyde Using Platinum/metal-oxide Catalysts -- a Gas-phased Kinetics Study PDF eBook |
Author | Yutichai Mueanngern |
Publisher | |
Pages | 70 |
Release | 2016 |
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In this thesis we studied the kinetics of crotonaldehyde hydrogenation on a series of Pt-cerium oxide and Pt-titanium dioxide catalysts to elucidate some mechanistic aspects of partial hydrogenation processes, which occurs on bi-functional catalyst systems. Studies in the literature have shown that the C=O bond hydrogenation of unsaturated aldehydes, more specifically of the crotonaldehyde species, only occurs when a platinum/metal-oxide interface exist, and does not occur on pure platinum or metal oxide surfaces. The mechanism of this process and the determination of the active site of crotonaldehyde have never been investigated. Because the presence of Pt/metal-oxide interfaces lead to this selective C=O bond hydrogenation, the active site is hypothesized to occur on the platinum/metal-oxide interface. However, possibilities of the active site being at the platinum sites or scaling with the metal-oxide sites remains. In this study we show that the active site occurs on the platinum within some distance from the interface of the two phases. We also show in this study that within a region of cerium oxide nanocubes which are uniformly packed on a platinum surface there exist no C=O bond activity, however at the interface between rafts of cerium oxide nanoparticles there exhibits significant enhancements to the C=O bond product. These results provide strong evidence that the chemistry for this C=O bond pathway extends beyond the three phase boundary of the platinum/metal-oxide alone. The results from this study provide insight into fundamental design parameters for designing highly selective bi-functional nanocatalysts.
Nanocatalysis
Title | Nanocatalysis PDF eBook |
Author | Vivek Polshettiwar |
Publisher | John Wiley & Sons |
Pages | 755 |
Release | 2013-09-30 |
Genre | Technology & Engineering |
ISBN | 111814886X |
Exhibiting both homogeneous and heterogeneous catalytic properties, nanocatalysts allow for rapid and selective chemical transformations, with the benefits of excellent product yield and ease of catalyst separation and recovery. This book reviews the catalytic performance and the synthesis and characterization of nanocatalysts, examining the current state of the art and pointing the way towards new avenues of research. Moreover, the authors discuss new and emerging applications of nanocatalysts and nanocatalysis, from pharmaceuticals to fine chemicals to renewable energy to biotransformations. Nanocatalysis features contributions from leading research groups around the world. These contributions reflect a thorough review of the current literature as well as the authors’ first-hand experience designing and synthesizing nanocatalysts and developing new applications for them. The book’s nineteen chapters offer a broad perspective, covering: Nanocatalysis for carbon-carbon and carbon-heteroatom coupling reactions Nanocatalysis for various organic transformations in fine chemical synthesis Nanocatalysis for oxidation, hydrogenation, and other related reactions Nanomaterial-based photocatalysis and biocatalysis Nanocatalysts to produce non-conventional energy such as hydrogen and biofuels Nanocatalysts and nano-biocatalysts in the chemical industry Readers will also learn about the latest spectroscopic and microscopy tools used in advanced characterization methods that shed new light on nanocatalysts and nanocatalysis. Moreover, the authors offer expert advice to help readers develop strategies to improve catalytic performance. Summarizing and reviewing all the most important advances in nanocatalysis over the last two decades, this book explains the many advantages of nanocatalysts over conventional homogeneous and heterogeneous catalysts, providing the information and guidance needed for designing green, sustainable catalytic processes.
Materials Handbook
Title | Materials Handbook PDF eBook |
Author | John A. Vaccari |
Publisher | McGraw Hill Professional |
Pages | 1244 |
Release | 2002-07-09 |
Genre | Technology & Engineering |
ISBN | 9780071501842 |
The Materials Handbook is an encyclopedic, A-to-Z organization of all types of materials, featuring their key performance properties, principal characteristics and applications in product design. Materials include ferrous and nonferrous metals, plastics, elastomers, ceramics, woods, composites, chemicals, minerals, textiles, fuels, foodstuffs and natural plant and animal substances --more than 13,000 in all. Properties are expressed in both U.S. customary and metric units and a thorough index eases finding details on each and every material. Introduced in 1929 and often known simply as "Brady's," this comprehensive, one-volume, 1244 page encyclopedia of materials is intended for executives, managers, supervisors, engineers, and technicians, in engineering, manufacturing, marketing, purchasing and sales as well as educators and students. Of the dozens of families of materials updated in the 15th Edition, the most extensive additions pertain to adhesives, activated carbon, aluminides, aluminum alloys, catalysts, ceramics, composites, fullerences, heat-transfer fluids, nanophase materials, nickel alloys, olefins, silicon nitride, stainless steels, thermoplastic elastomers, titanium alloys, tungsten alloys, valve alloys and welding and hard-facing alloys. Also widely updated are acrylics, brazing alloys, chelants, biodegradable plastics, molybdenum alloys, plastic alloys, recyclate plastics, superalloys, supercritical fluids and tool steels. New classes of materials added include aliphatic polyketones, carburizing secondary-hardening steels and polyarylene ether benzimidazoles. Carcinogens and materials likely to be cancer-causing in humans are listed for the first time.
Chemical Abstracts
Title | Chemical Abstracts PDF eBook |
Author | |
Publisher | |
Pages | 2676 |
Release | 2002 |
Genre | Chemistry |
ISBN |