A5064076639- Catalytic Processes in Materials Science
- Nanomaterials for catalytic reactions
- Catalysis and Oxidation Reactions
- Oxidative Organic Chemistry Reactions
- Catalysis for Biomass Conversion
- Catalysis and Hydrodesulfurization Studies
- Electrocatalysts for Energy Conversion
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Innovative Microfluidic and Catalytic Techniques Innovation
- Carbon dioxide utilization in catalysis
- Catalysts for Methane Reforming
- Crystallography and molecular interactions
- Mesoporous Materials and Catalysis
- Nanocluster Synthesis and Applications
- Asymmetric Hydrogenation and Catalysis
- Chemical Synthesis and Reactions
- biodegradable polymer synthesis and properties
- Free Radicals and Antioxidants
- Chemistry and Chemical Engineering
- Advanced Photocatalysis Techniques
- Minerals Flotation and Separation Techniques
- Carbon Dioxide Capture Technologies
- nanoparticles nucleation surface interactions
- Ammonia Synthesis and Nitrogen Reduction
Cardiff University
2015-2024
Total (United Kingdom)
2017
Utrecht University
2012-2016
Cancer Genomics Centre
2016
New York University Press
2015
University College London
2015
KU Leuven
2015
University of Liverpool
2015
Cambridge University Press
2015
National Chemical Laboratory
2004-2014
Abstract The catalytic hydrogenation of levulinic acid, a key platform molecule in many biorefinery schemes, into γ-valerolactone is considered as one the pivotal reactions to convert lignocellulose-based biomass renewable fuels and chemicals. Here we report on development highly active, selective stable supported metal catalysts for this reaction beneficial effects nano-alloying. Bimetallic random alloys gold-palladium ruthenium-palladium titanium dioxide are prepared with modified...
The oxidation of 5-hydroxymethyl-2-furfural was studied under mild reaction conditions using TiO2-supported Au and Au–Cu catalysts synthesized from pre-formed nanoparticles. Bimetallic gold-copper display superior activity as compared to monometallic gold. Moreover, after reaction, the bimetallic can be recovered by filtration reused without significant loss selectivity whereas gold materials are not stable. STEM-HAADF imagining XEDS spectra obtained show that particles homogeneous AuCu...
Au–Pt alloy nanoparticles deposited on Mg(OH)2 (see STEM-HAADF image) show high activity in the selective oxidation of polyols using molecular oxygen as oxidant at mild and base-free conditions. Glycerol is a by-product manufacture biodiesel its supply sustainable raw material anticipated to grow steadily due shift towards "greener" fuels. Since glycerol provides precursor various industrially valuable products, such glyceric acid, tartronic acid hydroxyacetone, this increasing represents an...
Lignin depolymerisation has received considerable attention recently due to the pressing need find sustainable alternatives fossil fuel feedstock produce chemicals and fuels. Two types of interunit linkages (C–C C–O linkages) link several aromatic units in structure lignin. Between these two inter-unit linkages, bond energies C–C are higher than that making them harder break. However, for an efficient lignin depolymerisation, both have be broken. This is more relevant because fact many...
We report a convenient excess anion modification and post-reduction step to the impregnation method which permits reproducible preparation of supported bimetallic AuPd nanoparticles having tight particle size distribution comparable that found for sol-immobilization materials but without complication ligands adsorbed on surface. The advantageous features modified compared those made by conventional include smaller average size, an optimized random alloy composition, improved compositional...
A key discovery in the last two decades has been realisation that gold, when prepared as supported nanoparticles, is exceptionally effective an oxidation catalyst, particularly for of carbon monoxide at sub-ambient temperature but also a number organic reactions synthetic significance. To some extent this observation counterintuitive since extended gold surfaces do not chemisorb oxygen, nor they corrode. For reactions, catalytic activity markedly enhanced by addition palladium. This paper...
The selective oxidation of furfural to furoic acid is achieved at mild reaction conditions over an AuPd/Mg(OH)<sub>2</sub> heterogeneous catalyst.
Efficient catalytic hydrogenation of nitroarenes to anilines with molecular hydrogen at room temperature is still a challenge. In this study, transformation was achieved by using photocatalyst SiC-supported segregated Pd and Au nanoparticles. Under visible-light irradiation, the nitrobenzene reached turnover frequency as high 1715 h–1 25 °C 0.1 MPa H2 pressure. This exceptional activity attributed synergistic effect nanoparticles on semiconducting SiC, which different from known electronic...
Abstract In the solvent‐free oxidation of benzyl alcohol to benzaldehyde using supported gold–palladium nanoparticles as catalysts, two pathways have been identified sources principal product, benzaldehyde. One is direct catalytic by O 2 , whereas second disproportionation molecules give equal amounts and toluene. Herein we report that changing metal oxide used support metal–nanoparticles catalyst from titania or niobium magnesium zinc oxide, it possible switch off reaction thereby...
The use of bio-renewable resources, such as glycerol, a by-product from bio-diesel manufacture, can provide viable way to make valuable products using greener technology. In particular, glycerol be reduced give 1,2-propanediol that then selectively oxidised lactate, which has immense potential monomer for the synthesis biodegradable polymers. We show gold-palladium alloy catalysts very effective selective oxidation lactate. Two supports, TiO2 and carbon, two preparation methods, wet...
Phosphotungstic acid (PTA) immobilized onto imidazole functionalized fumed silica and was used as an efficient catalyst for epoxidation of a variety olefins using aqueous H2O2 oxidant. Negligible leaching PTA under the reaction conditions employed indicates strong interaction between imidazole. The catalysts could be separated reused after catalytic cycle. Evidence heterogenization on has been inferred from different spectroscopic techniques like IR, UV−vis, NMR. Importantly, nature binding...
Bimetallic Au-Pd nanoparticles supported on TiO2 show excellent catalytic activity and selectivity to benzaldehyde in the solvent-free transformation of benzyl alcohol benzaldehyde, where toluene is main observed by-product, together with smaller amounts benzoic acid, benzoate dibenzyl ether. However, despite industrial relevance this reaction importance tuning desired only a few attempts have been made literature modeling kinetics for quantitative description system. A kinetic model...
The hydrodynamics of a three-phase micro-packed bed reactor and its effect on catalysed benzyl alcohol oxidation with pure oxygen were studied in silicon–glass microstructured reactor. microreactor was operated at 120 °C 1 barg contained channel 300 μm×600 μm cross-section, packed wt% Au–Pd/TiO2 catalyst, 65 average diameter. Improvements the conversion selectivity to benzaldehyde observed increasing gas-to-liquid ratio, which coincided change flow pattern from liquid-dominated slug...
Abstract Glycolic acid is an important chemical that has uses as a cleaning agent well intermediate. At present glycolic manufactured from either chloroacetic or formaldehyde hydrocyanation, both routes being nongreen and using nonsustainable resources. We investigate the possibility of producing glycolate oxidation glycerol, sustainable raw material. show by 1 % wt Au/carbon catalysts prepared sol‐immobilization method yields ca. 60 can be achieved, hydrogen peroxide oxidant in autoclave...
Trimetallic Au-Pd-Pt nanoparticles have been supported on activated carbon by the sol-immobilisation method. They are found to be highly active and selective catalysts for solvent-free aerobic oxidation of benzyl alcohol. The addition Pt promotes selectivity desired product benzaldehyde at expense toluene formation. Detailed aberration corrected STEM-XEDS analysis confirmed that particles indeed ternary alloys, but also identified composition fluctuations from particle-to-particle which vary...
This review article gives an overview of the recent developments in synthesis strategies supported gold-based bimetallic nanoparticle catalysts. The catalytic efficiency these nanoparticles, similar to monometallic depends on their structural characteristics, but with added complexities because presence second metal. We discuss three major features namely (a) size, (b) composition and (c) nanostructure, all which play a crucial role resulting overall performances materials. Selected...
Disproportionation of benzyl alcohol has been identified as the source toluene formation in solvent free oxidation using supported gold palladium catalysts. There is a slight increase disproportionation reaction, and hence selectivity, when this reaction performed continuous mode micro-packed bed reactor compared to same conventional glass stirred batch reactor. Oxidation reactions respond slightly differently changes parameters, like oxygen concentration pressure, micro packed was used...
Supported Au–Pd nanoparticles are shown to be effective catalysts for the transformation of glycerol into carbonate. The reaction with urea form carbonate is a very attractive that utilises two inexpensive and readily available raw materials in chemical cycle that, overall, results fixation carbon dioxide. Previous reports largely based on utilisation high concentrations metal sulphates or oxides, which suffer from low intrinsic activity selectivity limited recoverability due dissolution...