Author: Arvind Karkal BhatPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Metal-doped Rare Earth Oxide Catalysts for Condensations to Ketones
Author: Arvind Karkal BhatTransition Metal Doped Rare-earth Metal Oxide Catalysts for Dry Reforming of Methane
Author: Bo LiPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Dry reforming of methane (DRM) is an environment-friendly and sustainable chemical technique, since it converts methane and CO2, two most abundant greenhouse gases, into syngas and other high value chemical products. The most common catalyst for DRM reaction is Ni due to its low cost and high catalytic activity but Ni-based catalysts undergo severe deactivation due to coking. transition metal (TM) doped rare earth oxide catalysts have shown promise in the high catalytic activity and coking resistance ability. This thesis applies the first principles calculation method to design Ni and Zr doped CeO2 catalyst model. Density functional theory (DFT+U) method is used to generate the structure-composition-stability relationships. The distribution of Zr with multiple concentrations have been studied in the CeO2 fluorite lattice. The oxygen vacancy effect has also been examined in the bulk and surface Ni-doped CeO2 bulk and surface structure to determine the most stable configuration. The surface chemistry study of Ni-doped CeO2 surface shows that hydrocarbon over the surface is always oxidized and prefers bonding to the oxygen site rather than the Ni site. This result can thermodynamically explain the reason of catalyst coking resistance.
Methyl Ketone Condensation over Tailored Metal Oxides
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Methyl ketones represent promising oxygenate intermediates that can be derived from lignocellulosic biomass via numerous conversion routes and subsequently coupled to produce precursors for renewable diesel and aviation fuels. Basic metal oxides are known to promote ketone coupling via condensation reactions, with magnesium oxide (MgO) providing an ideal catalytic system for evaluating the reaction mechanism and role of water on observed activity. Recent studies demonstrate that the MgO(111) surface facet can be promoted to enhance activity for base catalyzed reactions; however, to our knowledge, there is a dearth of information regarding the impact of MgO(111) faceting and surface termination under reaction conditions for ketone coupling. Therefore, this talk will discuss our recent investigation into the catalytic coupling of methyl ketones over MgO(100) and MgO(111) catalysts. Results will be presented that address the synthesis and detailed characterization of MgO(111) nanosheets, as well as their activity and selectivity for ketone coupling when compared to MgO(100). The impact of water on MgO surface termination will be discussed, as well as a proposed reaction mechanism for ketone condensation over clean and hydroxyl terminated surfaces for both facets. Findings will include outcomes from experimental studies, computational modeling, and advanced surface characterization by neutron scattering. Collectively, this work provides further insight into the role of tailored metal oxide catalysts for this important class of biomass conversion chemistry.
Rare-Earth Oxide Catalysts for Asymmetric Ketone Synthesis
Author: Kerry M. DooleyPublisher:
ISBN:
Category : Chemical engineering
Languages : en
Pages : 39
Book Description
Synthesis of Earth Abundant, Non Toxic Mixed Metal Oxide Catalysts for Conversion of Renewable Carbon Sources to Drop-in Fuels
Author: Justin William WeberPublisher:
ISBN:
Category :
Languages : en
Pages : 292
Book Description
A 2-stage catalytic process for converting bio-oil oxygenates to higher value compounds for drop-in fuels was proposed. Ketonization using iron oxide catalysts prepared from red mud was implemented in a packed bed reactor system using model compounds. High levels of acetone (15-25 g/L), 2-butanone (~5 g/L), and cyclic ketones (9-13 g/L) were observed. Time-on-stream studies (8 h) indicated no measurable decline in conversion of acetol, formic acid, and levoglucosan, and only a 4% decline in acetic acid conversion. The effect of reduction pretreatment temperature on activity and surface properties of red mud was studied. Hydrogenation of ketonization products was conducted in continuous reactions using iron oxides and Pd-C catalysts. The best results were achieved in reactions using Pd-ACM (monoliths) at 180°C and 300 psi (H2), which converted ketones to alcohols at ~60-80%. Pd-C monoliths achieved higher space time yields and conversions compared to Pd-C granules.
Metal Oxide-Based Heterostructures
Author: Naveen KumarPublisher: Elsevier
ISBN: 0323860176
Category : Technology & Engineering
Languages : en
Pages : 610
Book Description
Metal Oxide–Based Heterostructures: Fabrication and Applications provides information on synthesis strategies, structural and hierarchical features, morphological characteristics of metal oxide–based heterostructures, and their diverse applications. This book begins with an introduction to the various multidimensional heterostructures, synthesis aspects, and techniques used to control the formation of heterostructures. Then, the impact of synthesis routes on the formation of mixed metal oxide heterostructures and their properties are analyzed. The effect of nonmetal doping, metal doping, and composites of metal oxide heterostructures on the properties of heterostructures is also addressed and that also includes opportunities for optimization of the material's performance for specific applications. Special attention is given to the surface characteristics of the metal oxide heterostructures and their impact on the material's performance, and the applications of metal oxide heterostructures in various fields such as environmental remediation, sensing, organic catalysis, photovoltaics, light emitting materials, and hydrogen production. - Introduces key principles for metal oxide heterostructures, their properties, key characteristics, and synthesis routes - Emphasizes the relationship between synthesis strategies and material performance, including optimization strategies such as tailoring the material's surface characteristics or structure - Discusses metal oxide heterostructures and their application in lighting and displays, energy, environment, and sensing
Catalytic Reduction of Nitric Oxide with Carbon Monoxide by Rare Earth Oxides and Noble Metal Catalysts
Author: Jen-Liang WuPublisher:
ISBN:
Category : Carbon monoxide
Languages : en
Pages : 542
Book Description
Catalyst Development for the Oxidative Coupling of Methane Utilizing Rare-Earth Oxide Based Catalysts
Author: Trenton W. ElkinsPublisher:
ISBN:
Category :
Languages : en
Pages : 227
Book Description
The alkali doped TbOx/n-MgO catalysts. The Li-TbOx/n-MgO catalyst was found to be more active and stable than supported samaria based catalysts, which is an incredible result. Furthermore, the deactivation associated with lithium doped catalysts was greatly reduced for our coimpregnated lithium containing catalyst and the Na-TbOx/n-MgO catalyst shows minimal deactivation under the same reaction conditions and is the most productive REO containing catalyst discovered in literature when considering production levels with long times on stream.
Fine Chemicals Through Heterogeneous Catalysis
Author: Roger A. SheldonPublisher: Wiley-VCH Verlag GmbH
ISBN:
Category : Science
Languages : en
Pages : 648
Book Description
Concentrating on the areas of fine chemicals production, this handbook presents current attempts to combine fine chemicals synthesis with heterogeneous catalysis - a new route to developing modern and clean synthetic methods.
Author: Changyi Jiang