Author: Federico CiminiPublisher:
ISBN:
Category :
Languages : en
Pages : 163
Book Description
The Structure of Supported Rhodium-platinum Catalysts
Author: Federico CiminiPublisher:
ISBN:
Category :
Languages : en
Pages : 163
Book Description
Characterization and Reaction Studies of Silica Supported Platinum and Rhodium Model Catalysts
Author: Matthew James LundwallPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The physical and catalytic properties of silica supported platinum or rhodium model catalysts are studied under both ultra high vacuum (UHV) and elevated pressure reaction conditions (>1torr). Platinum or rhodium nanoparticles are vapor deposited onto a SiO2/Mo(112) surface and characterized using various surface analytical methods. CO chemisorption is utilized as a surface probe to estimate the concentration of various sites on the nanoparticles through thermal desorption spectroscopy (TDS) and infrared reflection absorption spectroscopy (IRAS) along with microscopy techniques to estimate particle size. The results are compared with hard sphere models of face centered cubic metals described as truncated cubo-octahedron. Results demonstrate the excellent agreement between chemisorption and hard sphere models in estimating the concentration of undercoordinated atoms on the nanoparticle surface. Surfaces are then subjected to high pressure reaction conditions to test the efficacy of utilizing the rate of a chemical reaction to obtain structural information about the surface. The surfaces are translated in-situ to a high pressure reaction cell where both structure insensitive and sensitive reactions are performed. Structure insensitive reactions (e.g. CO oxidation) allow a method to calculate the total active area on a per atom basis for silica supported platinum and rhodium model catalysts under reaction conditions. While structure sensitive reactions allow an estimate of the types of reaction sites, such as step sites ([less than or equal to]C7) under reaction conditions (e.g. n-heptane dehydrocyclization). High pressure structure sensitive reactions (e.g. ethylene hydroformylation) are also shown to drastically alter the morphology of the surface by dispersing nanoparticles leading to inhibition of catalytic pathways. Moreover, the relationships between high index single crystals, oxide supported nanoparticles, and high surface area technical catalysts are established. Overall, the results demonstrate the utility of model catalysts in understanding the structure-activity relationships in heterogeneous catalytic reactions and the usefulness of high pressure reactions as an analytical probe of surface morphology.
The Structure and Catalytic Properties of Supported Platinum Catalysts
Author: Marinus VaarkampPublisher:
ISBN:
Category :
Languages : en
Pages : 166
Book Description
A Study on the Surface Structure of Supported Platinum Catalysts
Author: Harold H. KungPublisher:
ISBN:
Category : Catalysts
Languages : en
Pages :
Book Description
Support and Metal Particle Size Effects on Platinum and Rhodium Model Catalysts
Author: Georgios S. ZafirisPublisher:
ISBN:
Category :
Languages : en
Pages : 378
Book Description
Molecular Rhodium Clusters and Platinum-rhodium Bimetallic Clusters on MgO and in Faujasites
Author: William A. WeberPublisher:
ISBN:
Category :
Languages : en
Pages : 842
Book Description
Performance of Rhodium and Platinum Supported Catalysts for Hydroformylation in Supercritical Carbon Dioxide
Author: Timothy T. TackPublisher:
ISBN:
Category : Hydroformylation
Languages : en
Pages : 348
Book Description
Studies in Synthesis-structure-function Relationships in Oxide-supported Platinum Catalysts
Author: F. E. DiasPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The Structure and Catalytic Properties of Supported Platinum Catalysts
Author: Marinus VaarkampPublisher:
ISBN:
Category :
Languages : en
Pages : 166
Book Description
Structure-performance Relationship of Rhodium Catalysts Supported on Ceria-doped Alumina Applied in Methane Steam Reforming
Author: Renata Bessa DuartePublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
