Acid Strength Controlled Reaction Pathways for the Catalytic Cracking of 1-Pentene to Propene over ZSM-5

The perfluoroaryl borane B(C6F5)3 is an effective catalyst for a variety of organic transformations. In the hydrosilation of carbonyl functions, it activates the silane rather than the carbonyl substrate. In allylstannation reactions, two competing reaction pathways are observed, one involving tin cation catalysis, the other "true" borane catalysis. For B(C6F5)3, the former mechanism dominates, while for the weaker Lewis acid PhB(C6F5)2, the latter pathway is more prominent. Thus, chiral boranes of similar Lewis acid strength to PhB(C6F5)2 have the potential to mediate asymmetric allylstannation of aldehyde substrates.

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Processing biomass-derived oxygenates in the oil refinery: Catalytic cracking (FCC) reaction pathways and role of catalyst

Journal of Catalysis ◽

10.1016/j.jcat.2007.01.023 ◽

2007 ◽

Vol 247 (2) ◽

pp. 307-327 ◽

Cited By ~ 379

Author(s):

A CORMA ◽

G HUBER ◽

L SAUVANAUD ◽

P OCONNOR

Keyword(s):

Catalytic Cracking ◽

Oil Refinery ◽

Reaction Pathways

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Fluidized Catalytic Cracking Catalyst Microstructure as Determined by A Scanning Ion Microprobe

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135113 ◽

1990 ◽

Vol 48 (2) ◽

pp. 302-303

Author(s):

J.K. Lampert ◽

G.S. Koermer ◽

J.M. Macaoy ◽

J.M. Chabala ◽

R. Levi-Setti

Keyword(s):

Catalytic Cracking ◽

Secondary Ion Mass Spectrometry ◽

Fuel Oil ◽

Ion Microprobe ◽

Fluidized Catalytic Cracking ◽

Ion Probe ◽

Silica Alumina ◽

Resolution Imaging ◽

The University ◽

High Spatial Resolution Imaging

We have used high spatial resolution imaging secondary ion mass spectrometry (SIMS) to differentiate mineralogical phases and to investigate chemical segregations in fluidized catalytic cracking (FCC) catalyst particles. The oil industry relies on heterogeneous catalysis using these catalysts to convert heavy hydrocarbon fractions into high quality gasoline and fuel oil components. Catalyst performance is strongly influenced by catalyst microstructure and composition, with different chemical reactions occurring at specific types of sites within the particle. The zeolitic portions of the particle, where the majority of the oil conversion occurs, can be clearly distinguished from the surrounding silica-alumina matrix in analytical SIMS images.The University of Chicago scanning ion microprobe (SIM) employed in this study has been described previously. For these analyses, the instrument was operated with a 40 keV, 10 pA Ga+ primary ion probe focused to a 30 nm FWHM spot. Elemental SIMS maps were obtained from 10×10 μm2 areas in times not exceeding 524s.

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An analytical microscopic study of metals in fluidized catalytic cracking catalyst

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145613 ◽

1986 ◽

Vol 44 ◽

pp. 854-855

Author(s):

Clifford S. Rainey

Keyword(s):

Electron Microscopy ◽

Spatial Distribution ◽

Catalytic Cracking ◽

Catalyst Deactivation ◽

Coke Formation ◽

Acid Sites ◽

Y Zeolite ◽

Fcc Catalyst ◽

Fluidized Catalytic Cracking ◽

High Regeneration

The spatial distribution of V and Ni deposited within fluidized catalytic cracking (FCC) catalyst is studied because these metals contribute to catalyst deactivation. Y zeolite in FCC microspheres are high SiO2 aluminosilicates with molecular-sized channels that contain a mixture of lanthanoids. They must withstand high regeneration temperatures and retain acid sites needed for cracking of hydrocarbons, a process essential for efficient gasoline production. Zeolite in combination with V to form vanadates, or less diffusion in the channels due to coke formation, may deactivate catalyst. Other factors such as metal "skins", microsphere sintering, and attrition may also be involved. SEM of FCC fracture surfaces, AEM of Y zeolite, and electron microscopy of this work are developed to better understand and minimize catalyst deactivation.

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