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Showing 1 to 17 of 17 for “"Bifunctional catalysts"”.
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Exploring Design Opportunities of Bifunctional Catalysts Using Density Functional Theory and Microkinetic Modeling
Several examples of catalysts that perform multiple site-specific functionalities under steady-state reaction conditions have been reported in the literature. The most common systems are bifunctional catalysts where each of the two distinct sites catalyzes different reaction steps independently. …
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Selective dehydration of polyols over solid acids and metal-acid bifunctional catalysts: Towards a catalytic toolbox for rational catalyst design
… and oxygen, and requires a new suite of catalysts to handle selective oxygen removal.</p> <p>Polyols are a particular class of compounds which consist of a carbon backbone and multiple hydroxyl groups. Most polyols are derived from biorenewable sources, ranging from glycerol, which comes …
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ASYMMETRIC ORGANOCATALYTIC HENRY REACTION OF β–SUBSTITUTED α-KETO ESTERS VIA DYNAMIC KINETIC RESOLUTION
… a-keto esters using cinchona alkaloid derived bifunctional catalyst via dynamic kinetic resolution. Chapter 1 presents a brief historical background and development of asymmetric catalysis. Particularly, the asymmetric organocatalysis is introduced in detail. Then the historical background and …
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The effect of zeolite type on the hydrocracking of long n-paraffins
… be conducted utilising either monofunctional or bifunctional catalysts. Monofunctional catalysts, such as the supported sulphided base metals or metal oxides utilised in many crude oil refineries, yield a product with minimal additional branching, as desired, though would contaminate the …
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SUSTAINABLE CATALYSIS VIA IRON AND ZINC COMPLEXES: FROM TUNABLE METALLATE SYSTEMS TO PHOTOCHEMICAL REACTIVITY
… use of iron and zinc complexes as sustainable catalysts for transformations of small, strained heterocycles in the field of carbon dioxide valorization, as well as the synthesis of iron complexes as catalysts for photochemical oxidation. In the first part of the work, tetrahalometallate …
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Tailored heterogeneous catalysts for biomass conversion
… development and optimization of heterogeneous catalysts designed to address pressing challenges in sustainable biomass conversion. The introductory chapter outlines the importance of catalysis in advancing sustainable technologies, highlighting the need for catalysts that balance high activity, …
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Fast microwave-assisted thermochemical conversion of biomass for biofuel production
… syngas to dimethyl ether (DME) on various bifunctional catalysts. In Chapter 2, the microwave heating characteristics of various biomass feedstocks and microwave absorbents were examined and compared. Experimental results show that microwave absorbents absorbed the microwave irradiation …
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Derivatisierungsreaktionen von Cinchona-Alkaloiden und eine Cinchona-Alkaloid-katalysierte asymmetrische Synthese von 2,5-Diarylphopholanen
… or suggesting use of those derivatives as organocatalysts or as ligands for transition metals. The second part of this thesis describes an asymmetric catalytic total synthesis of (2R,5R)-diphenylphospholanic acid (Fiaud’s acid; 1-hydroxy-1r-oxo-2c,5t-diphenylphospholane). We have developed a …
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Multifunctioning Electrocatalytic Cathodes for Lithium-Air and Lithium-Oxygen Batteries
… to achieve this goal is by introducing novel bifunctional electrocatalysts at the battery cathode, enhancing the cycle life and the discharge capacity of the LABs and LOBs via promoting oxygen reaction kinetics. My PhD study is focused on developing transition metal derivative-based novel …
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Novel sulfur containing electrophiles in asymmetric organocatalysis
… with chiral thioureas. We also demonstrated that bifunctional catalysts are the catalysts of choice for many organocatalyzed processes. Furthermore, the reactivity of alpha,beta-unsaturated sulfonates in various reactions has been evaluated. It has been shown that organocatalyzed reactions with …
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Fundamental understanding and design principles of oxide/metal surfaces for lithium storage
… Li2O2-filled composite electrodes with various catalysts. It is found that the electro-oxidation of Li2O2 can be significantly catalysed by the presence of Pt/C. With insights obtained from the model system studies, we designed bimetallic PtAu nanoparticles as bifunctional catalysts for Li-O2 …
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Development and Application of Computational Methods for the Prediction of Chiral Phosphoric Acid Catalyst Performance
Chiral phosphoric acids are bifunctional catalysts that have the ability to activate electrophiles and nucleophiles through hydrogen bonding, and they have been successful in catalysing highly enantioselective additions of a wide range of nucleophiles to imines. In most literature reports it is not …
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Conversion of methyl ethyl ketone (MEK) to valuable chemicals over multifunctional supported catalysts
… of MEK to butene over supported copper catalysts (Cu-Al₂O₃, Cu-zeolite Y sodium (Cu-ZYNa) and Cu-zeolite Y hydrogen (Cu-ZYH)) in a fixed bed reactor. In this reaction, MEK is hydrogenated to 2-butanol over metal sites, and further dehydrated on acid sites to produce butene. Experimental …
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Simultaneous production of methanol and dimethylether from synthesis gas
… in an one-step (direct) process using a hybrid (bifunctional) catalyst system that permits both methanol synthesis and dehydration in a single process unit. In the present research work the production of DME has been studied by applying both the indirect and direct processes. Firstly, the …
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Valorización de etanol y acetona mediante procesos catalíticos
… For this purpose, reducing conditions and bifunctional catalysts (with metal nanoparticles) were considered (M/Mg Al, M: Ni, Co, Pd, Ru and Cu). The M/Mg Al catalysts improve the results obtained with the original support, especially at the lowest temperatures, at which side reactions are …
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SOLID-SUPPORTED PORPHYRINS FOR CATALYSIS AND SENSING
… catalytic efficiency of CC-based heterogeneous catalysts. Before testing the heterogeneous catalyst, the catalytic activity of the hemin derivative (5) was investigated under homogeneous conditions, which was obtained by the esterification of the carboxyl groups of hemin and the replacement of …